xref: /linux/net/ceph/osd_client.c (revision c5d3cdad688ed75fb311a3a671eb30ba7106d7d3)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/ceph/ceph_debug.h>
4 
5 #include <linux/module.h>
6 #include <linux/err.h>
7 #include <linux/highmem.h>
8 #include <linux/mm.h>
9 #include <linux/pagemap.h>
10 #include <linux/slab.h>
11 #include <linux/uaccess.h>
12 #ifdef CONFIG_BLOCK
13 #include <linux/bio.h>
14 #endif
15 
16 #include <linux/ceph/ceph_features.h>
17 #include <linux/ceph/libceph.h>
18 #include <linux/ceph/osd_client.h>
19 #include <linux/ceph/messenger.h>
20 #include <linux/ceph/decode.h>
21 #include <linux/ceph/auth.h>
22 #include <linux/ceph/pagelist.h>
23 #include <linux/ceph/striper.h>
24 
25 #define OSD_OPREPLY_FRONT_LEN	512
26 
27 static struct kmem_cache	*ceph_osd_request_cache;
28 
29 static const struct ceph_connection_operations osd_con_ops;
30 
31 /*
32  * Implement client access to distributed object storage cluster.
33  *
34  * All data objects are stored within a cluster/cloud of OSDs, or
35  * "object storage devices."  (Note that Ceph OSDs have _nothing_ to
36  * do with the T10 OSD extensions to SCSI.)  Ceph OSDs are simply
37  * remote daemons serving up and coordinating consistent and safe
38  * access to storage.
39  *
40  * Cluster membership and the mapping of data objects onto storage devices
41  * are described by the osd map.
42  *
43  * We keep track of pending OSD requests (read, write), resubmit
44  * requests to different OSDs when the cluster topology/data layout
45  * change, or retry the affected requests when the communications
46  * channel with an OSD is reset.
47  */
48 
49 static void link_request(struct ceph_osd *osd, struct ceph_osd_request *req);
50 static void unlink_request(struct ceph_osd *osd, struct ceph_osd_request *req);
51 static void link_linger(struct ceph_osd *osd,
52 			struct ceph_osd_linger_request *lreq);
53 static void unlink_linger(struct ceph_osd *osd,
54 			  struct ceph_osd_linger_request *lreq);
55 static void clear_backoffs(struct ceph_osd *osd);
56 
57 #if 1
58 static inline bool rwsem_is_wrlocked(struct rw_semaphore *sem)
59 {
60 	bool wrlocked = true;
61 
62 	if (unlikely(down_read_trylock(sem))) {
63 		wrlocked = false;
64 		up_read(sem);
65 	}
66 
67 	return wrlocked;
68 }
69 static inline void verify_osdc_locked(struct ceph_osd_client *osdc)
70 {
71 	WARN_ON(!rwsem_is_locked(&osdc->lock));
72 }
73 static inline void verify_osdc_wrlocked(struct ceph_osd_client *osdc)
74 {
75 	WARN_ON(!rwsem_is_wrlocked(&osdc->lock));
76 }
77 static inline void verify_osd_locked(struct ceph_osd *osd)
78 {
79 	struct ceph_osd_client *osdc = osd->o_osdc;
80 
81 	WARN_ON(!(mutex_is_locked(&osd->lock) &&
82 		  rwsem_is_locked(&osdc->lock)) &&
83 		!rwsem_is_wrlocked(&osdc->lock));
84 }
85 static inline void verify_lreq_locked(struct ceph_osd_linger_request *lreq)
86 {
87 	WARN_ON(!mutex_is_locked(&lreq->lock));
88 }
89 #else
90 static inline void verify_osdc_locked(struct ceph_osd_client *osdc) { }
91 static inline void verify_osdc_wrlocked(struct ceph_osd_client *osdc) { }
92 static inline void verify_osd_locked(struct ceph_osd *osd) { }
93 static inline void verify_lreq_locked(struct ceph_osd_linger_request *lreq) { }
94 #endif
95 
96 /*
97  * calculate the mapping of a file extent onto an object, and fill out the
98  * request accordingly.  shorten extent as necessary if it crosses an
99  * object boundary.
100  *
101  * fill osd op in request message.
102  */
103 static int calc_layout(struct ceph_file_layout *layout, u64 off, u64 *plen,
104 			u64 *objnum, u64 *objoff, u64 *objlen)
105 {
106 	u64 orig_len = *plen;
107 	u32 xlen;
108 
109 	/* object extent? */
110 	ceph_calc_file_object_mapping(layout, off, orig_len, objnum,
111 					  objoff, &xlen);
112 	*objlen = xlen;
113 	if (*objlen < orig_len) {
114 		*plen = *objlen;
115 		dout(" skipping last %llu, final file extent %llu~%llu\n",
116 		     orig_len - *plen, off, *plen);
117 	}
118 
119 	dout("calc_layout objnum=%llx %llu~%llu\n", *objnum, *objoff, *objlen);
120 	return 0;
121 }
122 
123 static void ceph_osd_data_init(struct ceph_osd_data *osd_data)
124 {
125 	memset(osd_data, 0, sizeof (*osd_data));
126 	osd_data->type = CEPH_OSD_DATA_TYPE_NONE;
127 }
128 
129 /*
130  * Consumes @pages if @own_pages is true.
131  */
132 static void ceph_osd_data_pages_init(struct ceph_osd_data *osd_data,
133 			struct page **pages, u64 length, u32 alignment,
134 			bool pages_from_pool, bool own_pages)
135 {
136 	osd_data->type = CEPH_OSD_DATA_TYPE_PAGES;
137 	osd_data->pages = pages;
138 	osd_data->length = length;
139 	osd_data->alignment = alignment;
140 	osd_data->pages_from_pool = pages_from_pool;
141 	osd_data->own_pages = own_pages;
142 }
143 
144 /*
145  * Consumes a ref on @pagelist.
146  */
147 static void ceph_osd_data_pagelist_init(struct ceph_osd_data *osd_data,
148 			struct ceph_pagelist *pagelist)
149 {
150 	osd_data->type = CEPH_OSD_DATA_TYPE_PAGELIST;
151 	osd_data->pagelist = pagelist;
152 }
153 
154 #ifdef CONFIG_BLOCK
155 static void ceph_osd_data_bio_init(struct ceph_osd_data *osd_data,
156 				   struct ceph_bio_iter *bio_pos,
157 				   u32 bio_length)
158 {
159 	osd_data->type = CEPH_OSD_DATA_TYPE_BIO;
160 	osd_data->bio_pos = *bio_pos;
161 	osd_data->bio_length = bio_length;
162 }
163 #endif /* CONFIG_BLOCK */
164 
165 static void ceph_osd_data_bvecs_init(struct ceph_osd_data *osd_data,
166 				     struct ceph_bvec_iter *bvec_pos,
167 				     u32 num_bvecs)
168 {
169 	osd_data->type = CEPH_OSD_DATA_TYPE_BVECS;
170 	osd_data->bvec_pos = *bvec_pos;
171 	osd_data->num_bvecs = num_bvecs;
172 }
173 
174 static struct ceph_osd_data *
175 osd_req_op_raw_data_in(struct ceph_osd_request *osd_req, unsigned int which)
176 {
177 	BUG_ON(which >= osd_req->r_num_ops);
178 
179 	return &osd_req->r_ops[which].raw_data_in;
180 }
181 
182 struct ceph_osd_data *
183 osd_req_op_extent_osd_data(struct ceph_osd_request *osd_req,
184 			unsigned int which)
185 {
186 	return osd_req_op_data(osd_req, which, extent, osd_data);
187 }
188 EXPORT_SYMBOL(osd_req_op_extent_osd_data);
189 
190 void osd_req_op_raw_data_in_pages(struct ceph_osd_request *osd_req,
191 			unsigned int which, struct page **pages,
192 			u64 length, u32 alignment,
193 			bool pages_from_pool, bool own_pages)
194 {
195 	struct ceph_osd_data *osd_data;
196 
197 	osd_data = osd_req_op_raw_data_in(osd_req, which);
198 	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
199 				pages_from_pool, own_pages);
200 }
201 EXPORT_SYMBOL(osd_req_op_raw_data_in_pages);
202 
203 void osd_req_op_extent_osd_data_pages(struct ceph_osd_request *osd_req,
204 			unsigned int which, struct page **pages,
205 			u64 length, u32 alignment,
206 			bool pages_from_pool, bool own_pages)
207 {
208 	struct ceph_osd_data *osd_data;
209 
210 	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
211 	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
212 				pages_from_pool, own_pages);
213 }
214 EXPORT_SYMBOL(osd_req_op_extent_osd_data_pages);
215 
216 void osd_req_op_extent_osd_data_pagelist(struct ceph_osd_request *osd_req,
217 			unsigned int which, struct ceph_pagelist *pagelist)
218 {
219 	struct ceph_osd_data *osd_data;
220 
221 	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
222 	ceph_osd_data_pagelist_init(osd_data, pagelist);
223 }
224 EXPORT_SYMBOL(osd_req_op_extent_osd_data_pagelist);
225 
226 #ifdef CONFIG_BLOCK
227 void osd_req_op_extent_osd_data_bio(struct ceph_osd_request *osd_req,
228 				    unsigned int which,
229 				    struct ceph_bio_iter *bio_pos,
230 				    u32 bio_length)
231 {
232 	struct ceph_osd_data *osd_data;
233 
234 	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
235 	ceph_osd_data_bio_init(osd_data, bio_pos, bio_length);
236 }
237 EXPORT_SYMBOL(osd_req_op_extent_osd_data_bio);
238 #endif /* CONFIG_BLOCK */
239 
240 void osd_req_op_extent_osd_data_bvecs(struct ceph_osd_request *osd_req,
241 				      unsigned int which,
242 				      struct bio_vec *bvecs, u32 num_bvecs,
243 				      u32 bytes)
244 {
245 	struct ceph_osd_data *osd_data;
246 	struct ceph_bvec_iter it = {
247 		.bvecs = bvecs,
248 		.iter = { .bi_size = bytes },
249 	};
250 
251 	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
252 	ceph_osd_data_bvecs_init(osd_data, &it, num_bvecs);
253 }
254 EXPORT_SYMBOL(osd_req_op_extent_osd_data_bvecs);
255 
256 void osd_req_op_extent_osd_data_bvec_pos(struct ceph_osd_request *osd_req,
257 					 unsigned int which,
258 					 struct ceph_bvec_iter *bvec_pos)
259 {
260 	struct ceph_osd_data *osd_data;
261 
262 	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
263 	ceph_osd_data_bvecs_init(osd_data, bvec_pos, 0);
264 }
265 EXPORT_SYMBOL(osd_req_op_extent_osd_data_bvec_pos);
266 
267 static void osd_req_op_cls_request_info_pagelist(
268 			struct ceph_osd_request *osd_req,
269 			unsigned int which, struct ceph_pagelist *pagelist)
270 {
271 	struct ceph_osd_data *osd_data;
272 
273 	osd_data = osd_req_op_data(osd_req, which, cls, request_info);
274 	ceph_osd_data_pagelist_init(osd_data, pagelist);
275 }
276 
277 void osd_req_op_cls_request_data_pagelist(
278 			struct ceph_osd_request *osd_req,
279 			unsigned int which, struct ceph_pagelist *pagelist)
280 {
281 	struct ceph_osd_data *osd_data;
282 
283 	osd_data = osd_req_op_data(osd_req, which, cls, request_data);
284 	ceph_osd_data_pagelist_init(osd_data, pagelist);
285 	osd_req->r_ops[which].cls.indata_len += pagelist->length;
286 	osd_req->r_ops[which].indata_len += pagelist->length;
287 }
288 EXPORT_SYMBOL(osd_req_op_cls_request_data_pagelist);
289 
290 void osd_req_op_cls_request_data_pages(struct ceph_osd_request *osd_req,
291 			unsigned int which, struct page **pages, u64 length,
292 			u32 alignment, bool pages_from_pool, bool own_pages)
293 {
294 	struct ceph_osd_data *osd_data;
295 
296 	osd_data = osd_req_op_data(osd_req, which, cls, request_data);
297 	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
298 				pages_from_pool, own_pages);
299 	osd_req->r_ops[which].cls.indata_len += length;
300 	osd_req->r_ops[which].indata_len += length;
301 }
302 EXPORT_SYMBOL(osd_req_op_cls_request_data_pages);
303 
304 void osd_req_op_cls_request_data_bvecs(struct ceph_osd_request *osd_req,
305 				       unsigned int which,
306 				       struct bio_vec *bvecs, u32 num_bvecs,
307 				       u32 bytes)
308 {
309 	struct ceph_osd_data *osd_data;
310 	struct ceph_bvec_iter it = {
311 		.bvecs = bvecs,
312 		.iter = { .bi_size = bytes },
313 	};
314 
315 	osd_data = osd_req_op_data(osd_req, which, cls, request_data);
316 	ceph_osd_data_bvecs_init(osd_data, &it, num_bvecs);
317 	osd_req->r_ops[which].cls.indata_len += bytes;
318 	osd_req->r_ops[which].indata_len += bytes;
319 }
320 EXPORT_SYMBOL(osd_req_op_cls_request_data_bvecs);
321 
322 void osd_req_op_cls_response_data_pages(struct ceph_osd_request *osd_req,
323 			unsigned int which, struct page **pages, u64 length,
324 			u32 alignment, bool pages_from_pool, bool own_pages)
325 {
326 	struct ceph_osd_data *osd_data;
327 
328 	osd_data = osd_req_op_data(osd_req, which, cls, response_data);
329 	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
330 				pages_from_pool, own_pages);
331 }
332 EXPORT_SYMBOL(osd_req_op_cls_response_data_pages);
333 
334 static u64 ceph_osd_data_length(struct ceph_osd_data *osd_data)
335 {
336 	switch (osd_data->type) {
337 	case CEPH_OSD_DATA_TYPE_NONE:
338 		return 0;
339 	case CEPH_OSD_DATA_TYPE_PAGES:
340 		return osd_data->length;
341 	case CEPH_OSD_DATA_TYPE_PAGELIST:
342 		return (u64)osd_data->pagelist->length;
343 #ifdef CONFIG_BLOCK
344 	case CEPH_OSD_DATA_TYPE_BIO:
345 		return (u64)osd_data->bio_length;
346 #endif /* CONFIG_BLOCK */
347 	case CEPH_OSD_DATA_TYPE_BVECS:
348 		return osd_data->bvec_pos.iter.bi_size;
349 	default:
350 		WARN(true, "unrecognized data type %d\n", (int)osd_data->type);
351 		return 0;
352 	}
353 }
354 
355 static void ceph_osd_data_release(struct ceph_osd_data *osd_data)
356 {
357 	if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGES && osd_data->own_pages) {
358 		int num_pages;
359 
360 		num_pages = calc_pages_for((u64)osd_data->alignment,
361 						(u64)osd_data->length);
362 		ceph_release_page_vector(osd_data->pages, num_pages);
363 	} else if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGELIST) {
364 		ceph_pagelist_release(osd_data->pagelist);
365 	}
366 	ceph_osd_data_init(osd_data);
367 }
368 
369 static void osd_req_op_data_release(struct ceph_osd_request *osd_req,
370 			unsigned int which)
371 {
372 	struct ceph_osd_req_op *op;
373 
374 	BUG_ON(which >= osd_req->r_num_ops);
375 	op = &osd_req->r_ops[which];
376 
377 	switch (op->op) {
378 	case CEPH_OSD_OP_READ:
379 	case CEPH_OSD_OP_WRITE:
380 	case CEPH_OSD_OP_WRITEFULL:
381 		ceph_osd_data_release(&op->extent.osd_data);
382 		break;
383 	case CEPH_OSD_OP_CALL:
384 		ceph_osd_data_release(&op->cls.request_info);
385 		ceph_osd_data_release(&op->cls.request_data);
386 		ceph_osd_data_release(&op->cls.response_data);
387 		break;
388 	case CEPH_OSD_OP_SETXATTR:
389 	case CEPH_OSD_OP_CMPXATTR:
390 		ceph_osd_data_release(&op->xattr.osd_data);
391 		break;
392 	case CEPH_OSD_OP_STAT:
393 		ceph_osd_data_release(&op->raw_data_in);
394 		break;
395 	case CEPH_OSD_OP_NOTIFY_ACK:
396 		ceph_osd_data_release(&op->notify_ack.request_data);
397 		break;
398 	case CEPH_OSD_OP_NOTIFY:
399 		ceph_osd_data_release(&op->notify.request_data);
400 		ceph_osd_data_release(&op->notify.response_data);
401 		break;
402 	case CEPH_OSD_OP_LIST_WATCHERS:
403 		ceph_osd_data_release(&op->list_watchers.response_data);
404 		break;
405 	case CEPH_OSD_OP_COPY_FROM2:
406 		ceph_osd_data_release(&op->copy_from.osd_data);
407 		break;
408 	default:
409 		break;
410 	}
411 }
412 
413 /*
414  * Assumes @t is zero-initialized.
415  */
416 static void target_init(struct ceph_osd_request_target *t)
417 {
418 	ceph_oid_init(&t->base_oid);
419 	ceph_oloc_init(&t->base_oloc);
420 	ceph_oid_init(&t->target_oid);
421 	ceph_oloc_init(&t->target_oloc);
422 
423 	ceph_osds_init(&t->acting);
424 	ceph_osds_init(&t->up);
425 	t->size = -1;
426 	t->min_size = -1;
427 
428 	t->osd = CEPH_HOMELESS_OSD;
429 }
430 
431 static void target_copy(struct ceph_osd_request_target *dest,
432 			const struct ceph_osd_request_target *src)
433 {
434 	ceph_oid_copy(&dest->base_oid, &src->base_oid);
435 	ceph_oloc_copy(&dest->base_oloc, &src->base_oloc);
436 	ceph_oid_copy(&dest->target_oid, &src->target_oid);
437 	ceph_oloc_copy(&dest->target_oloc, &src->target_oloc);
438 
439 	dest->pgid = src->pgid; /* struct */
440 	dest->spgid = src->spgid; /* struct */
441 	dest->pg_num = src->pg_num;
442 	dest->pg_num_mask = src->pg_num_mask;
443 	ceph_osds_copy(&dest->acting, &src->acting);
444 	ceph_osds_copy(&dest->up, &src->up);
445 	dest->size = src->size;
446 	dest->min_size = src->min_size;
447 	dest->sort_bitwise = src->sort_bitwise;
448 
449 	dest->flags = src->flags;
450 	dest->paused = src->paused;
451 
452 	dest->epoch = src->epoch;
453 	dest->last_force_resend = src->last_force_resend;
454 
455 	dest->osd = src->osd;
456 }
457 
458 static void target_destroy(struct ceph_osd_request_target *t)
459 {
460 	ceph_oid_destroy(&t->base_oid);
461 	ceph_oloc_destroy(&t->base_oloc);
462 	ceph_oid_destroy(&t->target_oid);
463 	ceph_oloc_destroy(&t->target_oloc);
464 }
465 
466 /*
467  * requests
468  */
469 static void request_release_checks(struct ceph_osd_request *req)
470 {
471 	WARN_ON(!RB_EMPTY_NODE(&req->r_node));
472 	WARN_ON(!RB_EMPTY_NODE(&req->r_mc_node));
473 	WARN_ON(!list_empty(&req->r_private_item));
474 	WARN_ON(req->r_osd);
475 }
476 
477 static void ceph_osdc_release_request(struct kref *kref)
478 {
479 	struct ceph_osd_request *req = container_of(kref,
480 					    struct ceph_osd_request, r_kref);
481 	unsigned int which;
482 
483 	dout("%s %p (r_request %p r_reply %p)\n", __func__, req,
484 	     req->r_request, req->r_reply);
485 	request_release_checks(req);
486 
487 	if (req->r_request)
488 		ceph_msg_put(req->r_request);
489 	if (req->r_reply)
490 		ceph_msg_put(req->r_reply);
491 
492 	for (which = 0; which < req->r_num_ops; which++)
493 		osd_req_op_data_release(req, which);
494 
495 	target_destroy(&req->r_t);
496 	ceph_put_snap_context(req->r_snapc);
497 
498 	if (req->r_mempool)
499 		mempool_free(req, req->r_osdc->req_mempool);
500 	else if (req->r_num_ops <= CEPH_OSD_SLAB_OPS)
501 		kmem_cache_free(ceph_osd_request_cache, req);
502 	else
503 		kfree(req);
504 }
505 
506 void ceph_osdc_get_request(struct ceph_osd_request *req)
507 {
508 	dout("%s %p (was %d)\n", __func__, req,
509 	     kref_read(&req->r_kref));
510 	kref_get(&req->r_kref);
511 }
512 EXPORT_SYMBOL(ceph_osdc_get_request);
513 
514 void ceph_osdc_put_request(struct ceph_osd_request *req)
515 {
516 	if (req) {
517 		dout("%s %p (was %d)\n", __func__, req,
518 		     kref_read(&req->r_kref));
519 		kref_put(&req->r_kref, ceph_osdc_release_request);
520 	}
521 }
522 EXPORT_SYMBOL(ceph_osdc_put_request);
523 
524 static void request_init(struct ceph_osd_request *req)
525 {
526 	/* req only, each op is zeroed in _osd_req_op_init() */
527 	memset(req, 0, sizeof(*req));
528 
529 	kref_init(&req->r_kref);
530 	init_completion(&req->r_completion);
531 	RB_CLEAR_NODE(&req->r_node);
532 	RB_CLEAR_NODE(&req->r_mc_node);
533 	INIT_LIST_HEAD(&req->r_private_item);
534 
535 	target_init(&req->r_t);
536 }
537 
538 /*
539  * This is ugly, but it allows us to reuse linger registration and ping
540  * requests, keeping the structure of the code around send_linger{_ping}()
541  * reasonable.  Setting up a min_nr=2 mempool for each linger request
542  * and dealing with copying ops (this blasts req only, watch op remains
543  * intact) isn't any better.
544  */
545 static void request_reinit(struct ceph_osd_request *req)
546 {
547 	struct ceph_osd_client *osdc = req->r_osdc;
548 	bool mempool = req->r_mempool;
549 	unsigned int num_ops = req->r_num_ops;
550 	u64 snapid = req->r_snapid;
551 	struct ceph_snap_context *snapc = req->r_snapc;
552 	bool linger = req->r_linger;
553 	struct ceph_msg *request_msg = req->r_request;
554 	struct ceph_msg *reply_msg = req->r_reply;
555 
556 	dout("%s req %p\n", __func__, req);
557 	WARN_ON(kref_read(&req->r_kref) != 1);
558 	request_release_checks(req);
559 
560 	WARN_ON(kref_read(&request_msg->kref) != 1);
561 	WARN_ON(kref_read(&reply_msg->kref) != 1);
562 	target_destroy(&req->r_t);
563 
564 	request_init(req);
565 	req->r_osdc = osdc;
566 	req->r_mempool = mempool;
567 	req->r_num_ops = num_ops;
568 	req->r_snapid = snapid;
569 	req->r_snapc = snapc;
570 	req->r_linger = linger;
571 	req->r_request = request_msg;
572 	req->r_reply = reply_msg;
573 }
574 
575 struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
576 					       struct ceph_snap_context *snapc,
577 					       unsigned int num_ops,
578 					       bool use_mempool,
579 					       gfp_t gfp_flags)
580 {
581 	struct ceph_osd_request *req;
582 
583 	if (use_mempool) {
584 		BUG_ON(num_ops > CEPH_OSD_SLAB_OPS);
585 		req = mempool_alloc(osdc->req_mempool, gfp_flags);
586 	} else if (num_ops <= CEPH_OSD_SLAB_OPS) {
587 		req = kmem_cache_alloc(ceph_osd_request_cache, gfp_flags);
588 	} else {
589 		BUG_ON(num_ops > CEPH_OSD_MAX_OPS);
590 		req = kmalloc(struct_size(req, r_ops, num_ops), gfp_flags);
591 	}
592 	if (unlikely(!req))
593 		return NULL;
594 
595 	request_init(req);
596 	req->r_osdc = osdc;
597 	req->r_mempool = use_mempool;
598 	req->r_num_ops = num_ops;
599 	req->r_snapid = CEPH_NOSNAP;
600 	req->r_snapc = ceph_get_snap_context(snapc);
601 
602 	dout("%s req %p\n", __func__, req);
603 	return req;
604 }
605 EXPORT_SYMBOL(ceph_osdc_alloc_request);
606 
607 static int ceph_oloc_encoding_size(const struct ceph_object_locator *oloc)
608 {
609 	return 8 + 4 + 4 + 4 + (oloc->pool_ns ? oloc->pool_ns->len : 0);
610 }
611 
612 static int __ceph_osdc_alloc_messages(struct ceph_osd_request *req, gfp_t gfp,
613 				      int num_request_data_items,
614 				      int num_reply_data_items)
615 {
616 	struct ceph_osd_client *osdc = req->r_osdc;
617 	struct ceph_msg *msg;
618 	int msg_size;
619 
620 	WARN_ON(req->r_request || req->r_reply);
621 	WARN_ON(ceph_oid_empty(&req->r_base_oid));
622 	WARN_ON(ceph_oloc_empty(&req->r_base_oloc));
623 
624 	/* create request message */
625 	msg_size = CEPH_ENCODING_START_BLK_LEN +
626 			CEPH_PGID_ENCODING_LEN + 1; /* spgid */
627 	msg_size += 4 + 4 + 4; /* hash, osdmap_epoch, flags */
628 	msg_size += CEPH_ENCODING_START_BLK_LEN +
629 			sizeof(struct ceph_osd_reqid); /* reqid */
630 	msg_size += sizeof(struct ceph_blkin_trace_info); /* trace */
631 	msg_size += 4 + sizeof(struct ceph_timespec); /* client_inc, mtime */
632 	msg_size += CEPH_ENCODING_START_BLK_LEN +
633 			ceph_oloc_encoding_size(&req->r_base_oloc); /* oloc */
634 	msg_size += 4 + req->r_base_oid.name_len; /* oid */
635 	msg_size += 2 + req->r_num_ops * sizeof(struct ceph_osd_op);
636 	msg_size += 8; /* snapid */
637 	msg_size += 8; /* snap_seq */
638 	msg_size += 4 + 8 * (req->r_snapc ? req->r_snapc->num_snaps : 0);
639 	msg_size += 4 + 8; /* retry_attempt, features */
640 
641 	if (req->r_mempool)
642 		msg = ceph_msgpool_get(&osdc->msgpool_op, msg_size,
643 				       num_request_data_items);
644 	else
645 		msg = ceph_msg_new2(CEPH_MSG_OSD_OP, msg_size,
646 				    num_request_data_items, gfp, true);
647 	if (!msg)
648 		return -ENOMEM;
649 
650 	memset(msg->front.iov_base, 0, msg->front.iov_len);
651 	req->r_request = msg;
652 
653 	/* create reply message */
654 	msg_size = OSD_OPREPLY_FRONT_LEN;
655 	msg_size += req->r_base_oid.name_len;
656 	msg_size += req->r_num_ops * sizeof(struct ceph_osd_op);
657 
658 	if (req->r_mempool)
659 		msg = ceph_msgpool_get(&osdc->msgpool_op_reply, msg_size,
660 				       num_reply_data_items);
661 	else
662 		msg = ceph_msg_new2(CEPH_MSG_OSD_OPREPLY, msg_size,
663 				    num_reply_data_items, gfp, true);
664 	if (!msg)
665 		return -ENOMEM;
666 
667 	req->r_reply = msg;
668 
669 	return 0;
670 }
671 
672 static bool osd_req_opcode_valid(u16 opcode)
673 {
674 	switch (opcode) {
675 #define GENERATE_CASE(op, opcode, str)	case CEPH_OSD_OP_##op: return true;
676 __CEPH_FORALL_OSD_OPS(GENERATE_CASE)
677 #undef GENERATE_CASE
678 	default:
679 		return false;
680 	}
681 }
682 
683 static void get_num_data_items(struct ceph_osd_request *req,
684 			       int *num_request_data_items,
685 			       int *num_reply_data_items)
686 {
687 	struct ceph_osd_req_op *op;
688 
689 	*num_request_data_items = 0;
690 	*num_reply_data_items = 0;
691 
692 	for (op = req->r_ops; op != &req->r_ops[req->r_num_ops]; op++) {
693 		switch (op->op) {
694 		/* request */
695 		case CEPH_OSD_OP_WRITE:
696 		case CEPH_OSD_OP_WRITEFULL:
697 		case CEPH_OSD_OP_SETXATTR:
698 		case CEPH_OSD_OP_CMPXATTR:
699 		case CEPH_OSD_OP_NOTIFY_ACK:
700 		case CEPH_OSD_OP_COPY_FROM2:
701 			*num_request_data_items += 1;
702 			break;
703 
704 		/* reply */
705 		case CEPH_OSD_OP_STAT:
706 		case CEPH_OSD_OP_READ:
707 		case CEPH_OSD_OP_LIST_WATCHERS:
708 			*num_reply_data_items += 1;
709 			break;
710 
711 		/* both */
712 		case CEPH_OSD_OP_NOTIFY:
713 			*num_request_data_items += 1;
714 			*num_reply_data_items += 1;
715 			break;
716 		case CEPH_OSD_OP_CALL:
717 			*num_request_data_items += 2;
718 			*num_reply_data_items += 1;
719 			break;
720 
721 		default:
722 			WARN_ON(!osd_req_opcode_valid(op->op));
723 			break;
724 		}
725 	}
726 }
727 
728 /*
729  * oid, oloc and OSD op opcode(s) must be filled in before this function
730  * is called.
731  */
732 int ceph_osdc_alloc_messages(struct ceph_osd_request *req, gfp_t gfp)
733 {
734 	int num_request_data_items, num_reply_data_items;
735 
736 	get_num_data_items(req, &num_request_data_items, &num_reply_data_items);
737 	return __ceph_osdc_alloc_messages(req, gfp, num_request_data_items,
738 					  num_reply_data_items);
739 }
740 EXPORT_SYMBOL(ceph_osdc_alloc_messages);
741 
742 /*
743  * This is an osd op init function for opcodes that have no data or
744  * other information associated with them.  It also serves as a
745  * common init routine for all the other init functions, below.
746  */
747 static struct ceph_osd_req_op *
748 _osd_req_op_init(struct ceph_osd_request *osd_req, unsigned int which,
749 		 u16 opcode, u32 flags)
750 {
751 	struct ceph_osd_req_op *op;
752 
753 	BUG_ON(which >= osd_req->r_num_ops);
754 	BUG_ON(!osd_req_opcode_valid(opcode));
755 
756 	op = &osd_req->r_ops[which];
757 	memset(op, 0, sizeof (*op));
758 	op->op = opcode;
759 	op->flags = flags;
760 
761 	return op;
762 }
763 
764 void osd_req_op_init(struct ceph_osd_request *osd_req,
765 		     unsigned int which, u16 opcode, u32 flags)
766 {
767 	(void)_osd_req_op_init(osd_req, which, opcode, flags);
768 }
769 EXPORT_SYMBOL(osd_req_op_init);
770 
771 void osd_req_op_extent_init(struct ceph_osd_request *osd_req,
772 				unsigned int which, u16 opcode,
773 				u64 offset, u64 length,
774 				u64 truncate_size, u32 truncate_seq)
775 {
776 	struct ceph_osd_req_op *op = _osd_req_op_init(osd_req, which,
777 						      opcode, 0);
778 	size_t payload_len = 0;
779 
780 	BUG_ON(opcode != CEPH_OSD_OP_READ && opcode != CEPH_OSD_OP_WRITE &&
781 	       opcode != CEPH_OSD_OP_WRITEFULL && opcode != CEPH_OSD_OP_ZERO &&
782 	       opcode != CEPH_OSD_OP_TRUNCATE);
783 
784 	op->extent.offset = offset;
785 	op->extent.length = length;
786 	op->extent.truncate_size = truncate_size;
787 	op->extent.truncate_seq = truncate_seq;
788 	if (opcode == CEPH_OSD_OP_WRITE || opcode == CEPH_OSD_OP_WRITEFULL)
789 		payload_len += length;
790 
791 	op->indata_len = payload_len;
792 }
793 EXPORT_SYMBOL(osd_req_op_extent_init);
794 
795 void osd_req_op_extent_update(struct ceph_osd_request *osd_req,
796 				unsigned int which, u64 length)
797 {
798 	struct ceph_osd_req_op *op;
799 	u64 previous;
800 
801 	BUG_ON(which >= osd_req->r_num_ops);
802 	op = &osd_req->r_ops[which];
803 	previous = op->extent.length;
804 
805 	if (length == previous)
806 		return;		/* Nothing to do */
807 	BUG_ON(length > previous);
808 
809 	op->extent.length = length;
810 	if (op->op == CEPH_OSD_OP_WRITE || op->op == CEPH_OSD_OP_WRITEFULL)
811 		op->indata_len -= previous - length;
812 }
813 EXPORT_SYMBOL(osd_req_op_extent_update);
814 
815 void osd_req_op_extent_dup_last(struct ceph_osd_request *osd_req,
816 				unsigned int which, u64 offset_inc)
817 {
818 	struct ceph_osd_req_op *op, *prev_op;
819 
820 	BUG_ON(which + 1 >= osd_req->r_num_ops);
821 
822 	prev_op = &osd_req->r_ops[which];
823 	op = _osd_req_op_init(osd_req, which + 1, prev_op->op, prev_op->flags);
824 	/* dup previous one */
825 	op->indata_len = prev_op->indata_len;
826 	op->outdata_len = prev_op->outdata_len;
827 	op->extent = prev_op->extent;
828 	/* adjust offset */
829 	op->extent.offset += offset_inc;
830 	op->extent.length -= offset_inc;
831 
832 	if (op->op == CEPH_OSD_OP_WRITE || op->op == CEPH_OSD_OP_WRITEFULL)
833 		op->indata_len -= offset_inc;
834 }
835 EXPORT_SYMBOL(osd_req_op_extent_dup_last);
836 
837 int osd_req_op_cls_init(struct ceph_osd_request *osd_req, unsigned int which,
838 			const char *class, const char *method)
839 {
840 	struct ceph_osd_req_op *op;
841 	struct ceph_pagelist *pagelist;
842 	size_t payload_len = 0;
843 	size_t size;
844 	int ret;
845 
846 	op = _osd_req_op_init(osd_req, which, CEPH_OSD_OP_CALL, 0);
847 
848 	pagelist = ceph_pagelist_alloc(GFP_NOFS);
849 	if (!pagelist)
850 		return -ENOMEM;
851 
852 	op->cls.class_name = class;
853 	size = strlen(class);
854 	BUG_ON(size > (size_t) U8_MAX);
855 	op->cls.class_len = size;
856 	ret = ceph_pagelist_append(pagelist, class, size);
857 	if (ret)
858 		goto err_pagelist_free;
859 	payload_len += size;
860 
861 	op->cls.method_name = method;
862 	size = strlen(method);
863 	BUG_ON(size > (size_t) U8_MAX);
864 	op->cls.method_len = size;
865 	ret = ceph_pagelist_append(pagelist, method, size);
866 	if (ret)
867 		goto err_pagelist_free;
868 	payload_len += size;
869 
870 	osd_req_op_cls_request_info_pagelist(osd_req, which, pagelist);
871 	op->indata_len = payload_len;
872 	return 0;
873 
874 err_pagelist_free:
875 	ceph_pagelist_release(pagelist);
876 	return ret;
877 }
878 EXPORT_SYMBOL(osd_req_op_cls_init);
879 
880 int osd_req_op_xattr_init(struct ceph_osd_request *osd_req, unsigned int which,
881 			  u16 opcode, const char *name, const void *value,
882 			  size_t size, u8 cmp_op, u8 cmp_mode)
883 {
884 	struct ceph_osd_req_op *op = _osd_req_op_init(osd_req, which,
885 						      opcode, 0);
886 	struct ceph_pagelist *pagelist;
887 	size_t payload_len;
888 	int ret;
889 
890 	BUG_ON(opcode != CEPH_OSD_OP_SETXATTR && opcode != CEPH_OSD_OP_CMPXATTR);
891 
892 	pagelist = ceph_pagelist_alloc(GFP_NOFS);
893 	if (!pagelist)
894 		return -ENOMEM;
895 
896 	payload_len = strlen(name);
897 	op->xattr.name_len = payload_len;
898 	ret = ceph_pagelist_append(pagelist, name, payload_len);
899 	if (ret)
900 		goto err_pagelist_free;
901 
902 	op->xattr.value_len = size;
903 	ret = ceph_pagelist_append(pagelist, value, size);
904 	if (ret)
905 		goto err_pagelist_free;
906 	payload_len += size;
907 
908 	op->xattr.cmp_op = cmp_op;
909 	op->xattr.cmp_mode = cmp_mode;
910 
911 	ceph_osd_data_pagelist_init(&op->xattr.osd_data, pagelist);
912 	op->indata_len = payload_len;
913 	return 0;
914 
915 err_pagelist_free:
916 	ceph_pagelist_release(pagelist);
917 	return ret;
918 }
919 EXPORT_SYMBOL(osd_req_op_xattr_init);
920 
921 /*
922  * @watch_opcode: CEPH_OSD_WATCH_OP_*
923  */
924 static void osd_req_op_watch_init(struct ceph_osd_request *req, int which,
925 				  u64 cookie, u8 watch_opcode)
926 {
927 	struct ceph_osd_req_op *op;
928 
929 	op = _osd_req_op_init(req, which, CEPH_OSD_OP_WATCH, 0);
930 	op->watch.cookie = cookie;
931 	op->watch.op = watch_opcode;
932 	op->watch.gen = 0;
933 }
934 
935 void osd_req_op_alloc_hint_init(struct ceph_osd_request *osd_req,
936 				unsigned int which,
937 				u64 expected_object_size,
938 				u64 expected_write_size)
939 {
940 	struct ceph_osd_req_op *op = _osd_req_op_init(osd_req, which,
941 						      CEPH_OSD_OP_SETALLOCHINT,
942 						      0);
943 
944 	op->alloc_hint.expected_object_size = expected_object_size;
945 	op->alloc_hint.expected_write_size = expected_write_size;
946 
947 	/*
948 	 * CEPH_OSD_OP_SETALLOCHINT op is advisory and therefore deemed
949 	 * not worth a feature bit.  Set FAILOK per-op flag to make
950 	 * sure older osds don't trip over an unsupported opcode.
951 	 */
952 	op->flags |= CEPH_OSD_OP_FLAG_FAILOK;
953 }
954 EXPORT_SYMBOL(osd_req_op_alloc_hint_init);
955 
956 static void ceph_osdc_msg_data_add(struct ceph_msg *msg,
957 				struct ceph_osd_data *osd_data)
958 {
959 	u64 length = ceph_osd_data_length(osd_data);
960 
961 	if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGES) {
962 		BUG_ON(length > (u64) SIZE_MAX);
963 		if (length)
964 			ceph_msg_data_add_pages(msg, osd_data->pages,
965 					length, osd_data->alignment, false);
966 	} else if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGELIST) {
967 		BUG_ON(!length);
968 		ceph_msg_data_add_pagelist(msg, osd_data->pagelist);
969 #ifdef CONFIG_BLOCK
970 	} else if (osd_data->type == CEPH_OSD_DATA_TYPE_BIO) {
971 		ceph_msg_data_add_bio(msg, &osd_data->bio_pos, length);
972 #endif
973 	} else if (osd_data->type == CEPH_OSD_DATA_TYPE_BVECS) {
974 		ceph_msg_data_add_bvecs(msg, &osd_data->bvec_pos);
975 	} else {
976 		BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_NONE);
977 	}
978 }
979 
980 static u32 osd_req_encode_op(struct ceph_osd_op *dst,
981 			     const struct ceph_osd_req_op *src)
982 {
983 	switch (src->op) {
984 	case CEPH_OSD_OP_STAT:
985 		break;
986 	case CEPH_OSD_OP_READ:
987 	case CEPH_OSD_OP_WRITE:
988 	case CEPH_OSD_OP_WRITEFULL:
989 	case CEPH_OSD_OP_ZERO:
990 	case CEPH_OSD_OP_TRUNCATE:
991 		dst->extent.offset = cpu_to_le64(src->extent.offset);
992 		dst->extent.length = cpu_to_le64(src->extent.length);
993 		dst->extent.truncate_size =
994 			cpu_to_le64(src->extent.truncate_size);
995 		dst->extent.truncate_seq =
996 			cpu_to_le32(src->extent.truncate_seq);
997 		break;
998 	case CEPH_OSD_OP_CALL:
999 		dst->cls.class_len = src->cls.class_len;
1000 		dst->cls.method_len = src->cls.method_len;
1001 		dst->cls.indata_len = cpu_to_le32(src->cls.indata_len);
1002 		break;
1003 	case CEPH_OSD_OP_WATCH:
1004 		dst->watch.cookie = cpu_to_le64(src->watch.cookie);
1005 		dst->watch.ver = cpu_to_le64(0);
1006 		dst->watch.op = src->watch.op;
1007 		dst->watch.gen = cpu_to_le32(src->watch.gen);
1008 		break;
1009 	case CEPH_OSD_OP_NOTIFY_ACK:
1010 		break;
1011 	case CEPH_OSD_OP_NOTIFY:
1012 		dst->notify.cookie = cpu_to_le64(src->notify.cookie);
1013 		break;
1014 	case CEPH_OSD_OP_LIST_WATCHERS:
1015 		break;
1016 	case CEPH_OSD_OP_SETALLOCHINT:
1017 		dst->alloc_hint.expected_object_size =
1018 		    cpu_to_le64(src->alloc_hint.expected_object_size);
1019 		dst->alloc_hint.expected_write_size =
1020 		    cpu_to_le64(src->alloc_hint.expected_write_size);
1021 		break;
1022 	case CEPH_OSD_OP_SETXATTR:
1023 	case CEPH_OSD_OP_CMPXATTR:
1024 		dst->xattr.name_len = cpu_to_le32(src->xattr.name_len);
1025 		dst->xattr.value_len = cpu_to_le32(src->xattr.value_len);
1026 		dst->xattr.cmp_op = src->xattr.cmp_op;
1027 		dst->xattr.cmp_mode = src->xattr.cmp_mode;
1028 		break;
1029 	case CEPH_OSD_OP_CREATE:
1030 	case CEPH_OSD_OP_DELETE:
1031 		break;
1032 	case CEPH_OSD_OP_COPY_FROM2:
1033 		dst->copy_from.snapid = cpu_to_le64(src->copy_from.snapid);
1034 		dst->copy_from.src_version =
1035 			cpu_to_le64(src->copy_from.src_version);
1036 		dst->copy_from.flags = src->copy_from.flags;
1037 		dst->copy_from.src_fadvise_flags =
1038 			cpu_to_le32(src->copy_from.src_fadvise_flags);
1039 		break;
1040 	default:
1041 		pr_err("unsupported osd opcode %s\n",
1042 			ceph_osd_op_name(src->op));
1043 		WARN_ON(1);
1044 
1045 		return 0;
1046 	}
1047 
1048 	dst->op = cpu_to_le16(src->op);
1049 	dst->flags = cpu_to_le32(src->flags);
1050 	dst->payload_len = cpu_to_le32(src->indata_len);
1051 
1052 	return src->indata_len;
1053 }
1054 
1055 /*
1056  * build new request AND message, calculate layout, and adjust file
1057  * extent as needed.
1058  *
1059  * if the file was recently truncated, we include information about its
1060  * old and new size so that the object can be updated appropriately.  (we
1061  * avoid synchronously deleting truncated objects because it's slow.)
1062  */
1063 struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
1064 					       struct ceph_file_layout *layout,
1065 					       struct ceph_vino vino,
1066 					       u64 off, u64 *plen,
1067 					       unsigned int which, int num_ops,
1068 					       int opcode, int flags,
1069 					       struct ceph_snap_context *snapc,
1070 					       u32 truncate_seq,
1071 					       u64 truncate_size,
1072 					       bool use_mempool)
1073 {
1074 	struct ceph_osd_request *req;
1075 	u64 objnum = 0;
1076 	u64 objoff = 0;
1077 	u64 objlen = 0;
1078 	int r;
1079 
1080 	BUG_ON(opcode != CEPH_OSD_OP_READ && opcode != CEPH_OSD_OP_WRITE &&
1081 	       opcode != CEPH_OSD_OP_ZERO && opcode != CEPH_OSD_OP_TRUNCATE &&
1082 	       opcode != CEPH_OSD_OP_CREATE && opcode != CEPH_OSD_OP_DELETE);
1083 
1084 	req = ceph_osdc_alloc_request(osdc, snapc, num_ops, use_mempool,
1085 					GFP_NOFS);
1086 	if (!req) {
1087 		r = -ENOMEM;
1088 		goto fail;
1089 	}
1090 
1091 	/* calculate max write size */
1092 	r = calc_layout(layout, off, plen, &objnum, &objoff, &objlen);
1093 	if (r)
1094 		goto fail;
1095 
1096 	if (opcode == CEPH_OSD_OP_CREATE || opcode == CEPH_OSD_OP_DELETE) {
1097 		osd_req_op_init(req, which, opcode, 0);
1098 	} else {
1099 		u32 object_size = layout->object_size;
1100 		u32 object_base = off - objoff;
1101 		if (!(truncate_seq == 1 && truncate_size == -1ULL)) {
1102 			if (truncate_size <= object_base) {
1103 				truncate_size = 0;
1104 			} else {
1105 				truncate_size -= object_base;
1106 				if (truncate_size > object_size)
1107 					truncate_size = object_size;
1108 			}
1109 		}
1110 		osd_req_op_extent_init(req, which, opcode, objoff, objlen,
1111 				       truncate_size, truncate_seq);
1112 	}
1113 
1114 	req->r_flags = flags;
1115 	req->r_base_oloc.pool = layout->pool_id;
1116 	req->r_base_oloc.pool_ns = ceph_try_get_string(layout->pool_ns);
1117 	ceph_oid_printf(&req->r_base_oid, "%llx.%08llx", vino.ino, objnum);
1118 
1119 	req->r_snapid = vino.snap;
1120 	if (flags & CEPH_OSD_FLAG_WRITE)
1121 		req->r_data_offset = off;
1122 
1123 	if (num_ops > 1)
1124 		/*
1125 		 * This is a special case for ceph_writepages_start(), but it
1126 		 * also covers ceph_uninline_data().  If more multi-op request
1127 		 * use cases emerge, we will need a separate helper.
1128 		 */
1129 		r = __ceph_osdc_alloc_messages(req, GFP_NOFS, num_ops, 0);
1130 	else
1131 		r = ceph_osdc_alloc_messages(req, GFP_NOFS);
1132 	if (r)
1133 		goto fail;
1134 
1135 	return req;
1136 
1137 fail:
1138 	ceph_osdc_put_request(req);
1139 	return ERR_PTR(r);
1140 }
1141 EXPORT_SYMBOL(ceph_osdc_new_request);
1142 
1143 /*
1144  * We keep osd requests in an rbtree, sorted by ->r_tid.
1145  */
1146 DEFINE_RB_FUNCS(request, struct ceph_osd_request, r_tid, r_node)
1147 DEFINE_RB_FUNCS(request_mc, struct ceph_osd_request, r_tid, r_mc_node)
1148 
1149 /*
1150  * Call @fn on each OSD request as long as @fn returns 0.
1151  */
1152 static void for_each_request(struct ceph_osd_client *osdc,
1153 			int (*fn)(struct ceph_osd_request *req, void *arg),
1154 			void *arg)
1155 {
1156 	struct rb_node *n, *p;
1157 
1158 	for (n = rb_first(&osdc->osds); n; n = rb_next(n)) {
1159 		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
1160 
1161 		for (p = rb_first(&osd->o_requests); p; ) {
1162 			struct ceph_osd_request *req =
1163 			    rb_entry(p, struct ceph_osd_request, r_node);
1164 
1165 			p = rb_next(p);
1166 			if (fn(req, arg))
1167 				return;
1168 		}
1169 	}
1170 
1171 	for (p = rb_first(&osdc->homeless_osd.o_requests); p; ) {
1172 		struct ceph_osd_request *req =
1173 		    rb_entry(p, struct ceph_osd_request, r_node);
1174 
1175 		p = rb_next(p);
1176 		if (fn(req, arg))
1177 			return;
1178 	}
1179 }
1180 
1181 static bool osd_homeless(struct ceph_osd *osd)
1182 {
1183 	return osd->o_osd == CEPH_HOMELESS_OSD;
1184 }
1185 
1186 static bool osd_registered(struct ceph_osd *osd)
1187 {
1188 	verify_osdc_locked(osd->o_osdc);
1189 
1190 	return !RB_EMPTY_NODE(&osd->o_node);
1191 }
1192 
1193 /*
1194  * Assumes @osd is zero-initialized.
1195  */
1196 static void osd_init(struct ceph_osd *osd)
1197 {
1198 	refcount_set(&osd->o_ref, 1);
1199 	RB_CLEAR_NODE(&osd->o_node);
1200 	osd->o_requests = RB_ROOT;
1201 	osd->o_linger_requests = RB_ROOT;
1202 	osd->o_backoff_mappings = RB_ROOT;
1203 	osd->o_backoffs_by_id = RB_ROOT;
1204 	INIT_LIST_HEAD(&osd->o_osd_lru);
1205 	INIT_LIST_HEAD(&osd->o_keepalive_item);
1206 	osd->o_incarnation = 1;
1207 	mutex_init(&osd->lock);
1208 }
1209 
1210 static void osd_cleanup(struct ceph_osd *osd)
1211 {
1212 	WARN_ON(!RB_EMPTY_NODE(&osd->o_node));
1213 	WARN_ON(!RB_EMPTY_ROOT(&osd->o_requests));
1214 	WARN_ON(!RB_EMPTY_ROOT(&osd->o_linger_requests));
1215 	WARN_ON(!RB_EMPTY_ROOT(&osd->o_backoff_mappings));
1216 	WARN_ON(!RB_EMPTY_ROOT(&osd->o_backoffs_by_id));
1217 	WARN_ON(!list_empty(&osd->o_osd_lru));
1218 	WARN_ON(!list_empty(&osd->o_keepalive_item));
1219 
1220 	if (osd->o_auth.authorizer) {
1221 		WARN_ON(osd_homeless(osd));
1222 		ceph_auth_destroy_authorizer(osd->o_auth.authorizer);
1223 	}
1224 }
1225 
1226 /*
1227  * Track open sessions with osds.
1228  */
1229 static struct ceph_osd *create_osd(struct ceph_osd_client *osdc, int onum)
1230 {
1231 	struct ceph_osd *osd;
1232 
1233 	WARN_ON(onum == CEPH_HOMELESS_OSD);
1234 
1235 	osd = kzalloc(sizeof(*osd), GFP_NOIO | __GFP_NOFAIL);
1236 	osd_init(osd);
1237 	osd->o_osdc = osdc;
1238 	osd->o_osd = onum;
1239 
1240 	ceph_con_init(&osd->o_con, osd, &osd_con_ops, &osdc->client->msgr);
1241 
1242 	return osd;
1243 }
1244 
1245 static struct ceph_osd *get_osd(struct ceph_osd *osd)
1246 {
1247 	if (refcount_inc_not_zero(&osd->o_ref)) {
1248 		dout("get_osd %p %d -> %d\n", osd, refcount_read(&osd->o_ref)-1,
1249 		     refcount_read(&osd->o_ref));
1250 		return osd;
1251 	} else {
1252 		dout("get_osd %p FAIL\n", osd);
1253 		return NULL;
1254 	}
1255 }
1256 
1257 static void put_osd(struct ceph_osd *osd)
1258 {
1259 	dout("put_osd %p %d -> %d\n", osd, refcount_read(&osd->o_ref),
1260 	     refcount_read(&osd->o_ref) - 1);
1261 	if (refcount_dec_and_test(&osd->o_ref)) {
1262 		osd_cleanup(osd);
1263 		kfree(osd);
1264 	}
1265 }
1266 
1267 DEFINE_RB_FUNCS(osd, struct ceph_osd, o_osd, o_node)
1268 
1269 static void __move_osd_to_lru(struct ceph_osd *osd)
1270 {
1271 	struct ceph_osd_client *osdc = osd->o_osdc;
1272 
1273 	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
1274 	BUG_ON(!list_empty(&osd->o_osd_lru));
1275 
1276 	spin_lock(&osdc->osd_lru_lock);
1277 	list_add_tail(&osd->o_osd_lru, &osdc->osd_lru);
1278 	spin_unlock(&osdc->osd_lru_lock);
1279 
1280 	osd->lru_ttl = jiffies + osdc->client->options->osd_idle_ttl;
1281 }
1282 
1283 static void maybe_move_osd_to_lru(struct ceph_osd *osd)
1284 {
1285 	if (RB_EMPTY_ROOT(&osd->o_requests) &&
1286 	    RB_EMPTY_ROOT(&osd->o_linger_requests))
1287 		__move_osd_to_lru(osd);
1288 }
1289 
1290 static void __remove_osd_from_lru(struct ceph_osd *osd)
1291 {
1292 	struct ceph_osd_client *osdc = osd->o_osdc;
1293 
1294 	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
1295 
1296 	spin_lock(&osdc->osd_lru_lock);
1297 	if (!list_empty(&osd->o_osd_lru))
1298 		list_del_init(&osd->o_osd_lru);
1299 	spin_unlock(&osdc->osd_lru_lock);
1300 }
1301 
1302 /*
1303  * Close the connection and assign any leftover requests to the
1304  * homeless session.
1305  */
1306 static void close_osd(struct ceph_osd *osd)
1307 {
1308 	struct ceph_osd_client *osdc = osd->o_osdc;
1309 	struct rb_node *n;
1310 
1311 	verify_osdc_wrlocked(osdc);
1312 	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
1313 
1314 	ceph_con_close(&osd->o_con);
1315 
1316 	for (n = rb_first(&osd->o_requests); n; ) {
1317 		struct ceph_osd_request *req =
1318 		    rb_entry(n, struct ceph_osd_request, r_node);
1319 
1320 		n = rb_next(n); /* unlink_request() */
1321 
1322 		dout(" reassigning req %p tid %llu\n", req, req->r_tid);
1323 		unlink_request(osd, req);
1324 		link_request(&osdc->homeless_osd, req);
1325 	}
1326 	for (n = rb_first(&osd->o_linger_requests); n; ) {
1327 		struct ceph_osd_linger_request *lreq =
1328 		    rb_entry(n, struct ceph_osd_linger_request, node);
1329 
1330 		n = rb_next(n); /* unlink_linger() */
1331 
1332 		dout(" reassigning lreq %p linger_id %llu\n", lreq,
1333 		     lreq->linger_id);
1334 		unlink_linger(osd, lreq);
1335 		link_linger(&osdc->homeless_osd, lreq);
1336 	}
1337 	clear_backoffs(osd);
1338 
1339 	__remove_osd_from_lru(osd);
1340 	erase_osd(&osdc->osds, osd);
1341 	put_osd(osd);
1342 }
1343 
1344 /*
1345  * reset osd connect
1346  */
1347 static int reopen_osd(struct ceph_osd *osd)
1348 {
1349 	struct ceph_entity_addr *peer_addr;
1350 
1351 	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
1352 
1353 	if (RB_EMPTY_ROOT(&osd->o_requests) &&
1354 	    RB_EMPTY_ROOT(&osd->o_linger_requests)) {
1355 		close_osd(osd);
1356 		return -ENODEV;
1357 	}
1358 
1359 	peer_addr = &osd->o_osdc->osdmap->osd_addr[osd->o_osd];
1360 	if (!memcmp(peer_addr, &osd->o_con.peer_addr, sizeof (*peer_addr)) &&
1361 			!ceph_con_opened(&osd->o_con)) {
1362 		struct rb_node *n;
1363 
1364 		dout("osd addr hasn't changed and connection never opened, "
1365 		     "letting msgr retry\n");
1366 		/* touch each r_stamp for handle_timeout()'s benfit */
1367 		for (n = rb_first(&osd->o_requests); n; n = rb_next(n)) {
1368 			struct ceph_osd_request *req =
1369 			    rb_entry(n, struct ceph_osd_request, r_node);
1370 			req->r_stamp = jiffies;
1371 		}
1372 
1373 		return -EAGAIN;
1374 	}
1375 
1376 	ceph_con_close(&osd->o_con);
1377 	ceph_con_open(&osd->o_con, CEPH_ENTITY_TYPE_OSD, osd->o_osd, peer_addr);
1378 	osd->o_incarnation++;
1379 
1380 	return 0;
1381 }
1382 
1383 static struct ceph_osd *lookup_create_osd(struct ceph_osd_client *osdc, int o,
1384 					  bool wrlocked)
1385 {
1386 	struct ceph_osd *osd;
1387 
1388 	if (wrlocked)
1389 		verify_osdc_wrlocked(osdc);
1390 	else
1391 		verify_osdc_locked(osdc);
1392 
1393 	if (o != CEPH_HOMELESS_OSD)
1394 		osd = lookup_osd(&osdc->osds, o);
1395 	else
1396 		osd = &osdc->homeless_osd;
1397 	if (!osd) {
1398 		if (!wrlocked)
1399 			return ERR_PTR(-EAGAIN);
1400 
1401 		osd = create_osd(osdc, o);
1402 		insert_osd(&osdc->osds, osd);
1403 		ceph_con_open(&osd->o_con, CEPH_ENTITY_TYPE_OSD, osd->o_osd,
1404 			      &osdc->osdmap->osd_addr[osd->o_osd]);
1405 	}
1406 
1407 	dout("%s osdc %p osd%d -> osd %p\n", __func__, osdc, o, osd);
1408 	return osd;
1409 }
1410 
1411 /*
1412  * Create request <-> OSD session relation.
1413  *
1414  * @req has to be assigned a tid, @osd may be homeless.
1415  */
1416 static void link_request(struct ceph_osd *osd, struct ceph_osd_request *req)
1417 {
1418 	verify_osd_locked(osd);
1419 	WARN_ON(!req->r_tid || req->r_osd);
1420 	dout("%s osd %p osd%d req %p tid %llu\n", __func__, osd, osd->o_osd,
1421 	     req, req->r_tid);
1422 
1423 	if (!osd_homeless(osd))
1424 		__remove_osd_from_lru(osd);
1425 	else
1426 		atomic_inc(&osd->o_osdc->num_homeless);
1427 
1428 	get_osd(osd);
1429 	insert_request(&osd->o_requests, req);
1430 	req->r_osd = osd;
1431 }
1432 
1433 static void unlink_request(struct ceph_osd *osd, struct ceph_osd_request *req)
1434 {
1435 	verify_osd_locked(osd);
1436 	WARN_ON(req->r_osd != osd);
1437 	dout("%s osd %p osd%d req %p tid %llu\n", __func__, osd, osd->o_osd,
1438 	     req, req->r_tid);
1439 
1440 	req->r_osd = NULL;
1441 	erase_request(&osd->o_requests, req);
1442 	put_osd(osd);
1443 
1444 	if (!osd_homeless(osd))
1445 		maybe_move_osd_to_lru(osd);
1446 	else
1447 		atomic_dec(&osd->o_osdc->num_homeless);
1448 }
1449 
1450 static bool __pool_full(struct ceph_pg_pool_info *pi)
1451 {
1452 	return pi->flags & CEPH_POOL_FLAG_FULL;
1453 }
1454 
1455 static bool have_pool_full(struct ceph_osd_client *osdc)
1456 {
1457 	struct rb_node *n;
1458 
1459 	for (n = rb_first(&osdc->osdmap->pg_pools); n; n = rb_next(n)) {
1460 		struct ceph_pg_pool_info *pi =
1461 		    rb_entry(n, struct ceph_pg_pool_info, node);
1462 
1463 		if (__pool_full(pi))
1464 			return true;
1465 	}
1466 
1467 	return false;
1468 }
1469 
1470 static bool pool_full(struct ceph_osd_client *osdc, s64 pool_id)
1471 {
1472 	struct ceph_pg_pool_info *pi;
1473 
1474 	pi = ceph_pg_pool_by_id(osdc->osdmap, pool_id);
1475 	if (!pi)
1476 		return false;
1477 
1478 	return __pool_full(pi);
1479 }
1480 
1481 /*
1482  * Returns whether a request should be blocked from being sent
1483  * based on the current osdmap and osd_client settings.
1484  */
1485 static bool target_should_be_paused(struct ceph_osd_client *osdc,
1486 				    const struct ceph_osd_request_target *t,
1487 				    struct ceph_pg_pool_info *pi)
1488 {
1489 	bool pauserd = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD);
1490 	bool pausewr = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR) ||
1491 		       ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
1492 		       __pool_full(pi);
1493 
1494 	WARN_ON(pi->id != t->target_oloc.pool);
1495 	return ((t->flags & CEPH_OSD_FLAG_READ) && pauserd) ||
1496 	       ((t->flags & CEPH_OSD_FLAG_WRITE) && pausewr) ||
1497 	       (osdc->osdmap->epoch < osdc->epoch_barrier);
1498 }
1499 
1500 enum calc_target_result {
1501 	CALC_TARGET_NO_ACTION = 0,
1502 	CALC_TARGET_NEED_RESEND,
1503 	CALC_TARGET_POOL_DNE,
1504 };
1505 
1506 static enum calc_target_result calc_target(struct ceph_osd_client *osdc,
1507 					   struct ceph_osd_request_target *t,
1508 					   bool any_change)
1509 {
1510 	struct ceph_pg_pool_info *pi;
1511 	struct ceph_pg pgid, last_pgid;
1512 	struct ceph_osds up, acting;
1513 	bool force_resend = false;
1514 	bool unpaused = false;
1515 	bool legacy_change = false;
1516 	bool split = false;
1517 	bool sort_bitwise = ceph_osdmap_flag(osdc, CEPH_OSDMAP_SORTBITWISE);
1518 	bool recovery_deletes = ceph_osdmap_flag(osdc,
1519 						 CEPH_OSDMAP_RECOVERY_DELETES);
1520 	enum calc_target_result ct_res;
1521 
1522 	t->epoch = osdc->osdmap->epoch;
1523 	pi = ceph_pg_pool_by_id(osdc->osdmap, t->base_oloc.pool);
1524 	if (!pi) {
1525 		t->osd = CEPH_HOMELESS_OSD;
1526 		ct_res = CALC_TARGET_POOL_DNE;
1527 		goto out;
1528 	}
1529 
1530 	if (osdc->osdmap->epoch == pi->last_force_request_resend) {
1531 		if (t->last_force_resend < pi->last_force_request_resend) {
1532 			t->last_force_resend = pi->last_force_request_resend;
1533 			force_resend = true;
1534 		} else if (t->last_force_resend == 0) {
1535 			force_resend = true;
1536 		}
1537 	}
1538 
1539 	/* apply tiering */
1540 	ceph_oid_copy(&t->target_oid, &t->base_oid);
1541 	ceph_oloc_copy(&t->target_oloc, &t->base_oloc);
1542 	if ((t->flags & CEPH_OSD_FLAG_IGNORE_OVERLAY) == 0) {
1543 		if (t->flags & CEPH_OSD_FLAG_READ && pi->read_tier >= 0)
1544 			t->target_oloc.pool = pi->read_tier;
1545 		if (t->flags & CEPH_OSD_FLAG_WRITE && pi->write_tier >= 0)
1546 			t->target_oloc.pool = pi->write_tier;
1547 
1548 		pi = ceph_pg_pool_by_id(osdc->osdmap, t->target_oloc.pool);
1549 		if (!pi) {
1550 			t->osd = CEPH_HOMELESS_OSD;
1551 			ct_res = CALC_TARGET_POOL_DNE;
1552 			goto out;
1553 		}
1554 	}
1555 
1556 	__ceph_object_locator_to_pg(pi, &t->target_oid, &t->target_oloc, &pgid);
1557 	last_pgid.pool = pgid.pool;
1558 	last_pgid.seed = ceph_stable_mod(pgid.seed, t->pg_num, t->pg_num_mask);
1559 
1560 	ceph_pg_to_up_acting_osds(osdc->osdmap, pi, &pgid, &up, &acting);
1561 	if (any_change &&
1562 	    ceph_is_new_interval(&t->acting,
1563 				 &acting,
1564 				 &t->up,
1565 				 &up,
1566 				 t->size,
1567 				 pi->size,
1568 				 t->min_size,
1569 				 pi->min_size,
1570 				 t->pg_num,
1571 				 pi->pg_num,
1572 				 t->sort_bitwise,
1573 				 sort_bitwise,
1574 				 t->recovery_deletes,
1575 				 recovery_deletes,
1576 				 &last_pgid))
1577 		force_resend = true;
1578 
1579 	if (t->paused && !target_should_be_paused(osdc, t, pi)) {
1580 		t->paused = false;
1581 		unpaused = true;
1582 	}
1583 	legacy_change = ceph_pg_compare(&t->pgid, &pgid) ||
1584 			ceph_osds_changed(&t->acting, &acting, any_change);
1585 	if (t->pg_num)
1586 		split = ceph_pg_is_split(&last_pgid, t->pg_num, pi->pg_num);
1587 
1588 	if (legacy_change || force_resend || split) {
1589 		t->pgid = pgid; /* struct */
1590 		ceph_pg_to_primary_shard(osdc->osdmap, pi, &pgid, &t->spgid);
1591 		ceph_osds_copy(&t->acting, &acting);
1592 		ceph_osds_copy(&t->up, &up);
1593 		t->size = pi->size;
1594 		t->min_size = pi->min_size;
1595 		t->pg_num = pi->pg_num;
1596 		t->pg_num_mask = pi->pg_num_mask;
1597 		t->sort_bitwise = sort_bitwise;
1598 		t->recovery_deletes = recovery_deletes;
1599 
1600 		t->osd = acting.primary;
1601 	}
1602 
1603 	if (unpaused || legacy_change || force_resend || split)
1604 		ct_res = CALC_TARGET_NEED_RESEND;
1605 	else
1606 		ct_res = CALC_TARGET_NO_ACTION;
1607 
1608 out:
1609 	dout("%s t %p -> %d%d%d%d ct_res %d osd%d\n", __func__, t, unpaused,
1610 	     legacy_change, force_resend, split, ct_res, t->osd);
1611 	return ct_res;
1612 }
1613 
1614 static struct ceph_spg_mapping *alloc_spg_mapping(void)
1615 {
1616 	struct ceph_spg_mapping *spg;
1617 
1618 	spg = kmalloc(sizeof(*spg), GFP_NOIO);
1619 	if (!spg)
1620 		return NULL;
1621 
1622 	RB_CLEAR_NODE(&spg->node);
1623 	spg->backoffs = RB_ROOT;
1624 	return spg;
1625 }
1626 
1627 static void free_spg_mapping(struct ceph_spg_mapping *spg)
1628 {
1629 	WARN_ON(!RB_EMPTY_NODE(&spg->node));
1630 	WARN_ON(!RB_EMPTY_ROOT(&spg->backoffs));
1631 
1632 	kfree(spg);
1633 }
1634 
1635 /*
1636  * rbtree of ceph_spg_mapping for handling map<spg_t, ...>, similar to
1637  * ceph_pg_mapping.  Used to track OSD backoffs -- a backoff [range] is
1638  * defined only within a specific spgid; it does not pass anything to
1639  * children on split, or to another primary.
1640  */
1641 DEFINE_RB_FUNCS2(spg_mapping, struct ceph_spg_mapping, spgid, ceph_spg_compare,
1642 		 RB_BYPTR, const struct ceph_spg *, node)
1643 
1644 static u64 hoid_get_bitwise_key(const struct ceph_hobject_id *hoid)
1645 {
1646 	return hoid->is_max ? 0x100000000ull : hoid->hash_reverse_bits;
1647 }
1648 
1649 static void hoid_get_effective_key(const struct ceph_hobject_id *hoid,
1650 				   void **pkey, size_t *pkey_len)
1651 {
1652 	if (hoid->key_len) {
1653 		*pkey = hoid->key;
1654 		*pkey_len = hoid->key_len;
1655 	} else {
1656 		*pkey = hoid->oid;
1657 		*pkey_len = hoid->oid_len;
1658 	}
1659 }
1660 
1661 static int compare_names(const void *name1, size_t name1_len,
1662 			 const void *name2, size_t name2_len)
1663 {
1664 	int ret;
1665 
1666 	ret = memcmp(name1, name2, min(name1_len, name2_len));
1667 	if (!ret) {
1668 		if (name1_len < name2_len)
1669 			ret = -1;
1670 		else if (name1_len > name2_len)
1671 			ret = 1;
1672 	}
1673 	return ret;
1674 }
1675 
1676 static int hoid_compare(const struct ceph_hobject_id *lhs,
1677 			const struct ceph_hobject_id *rhs)
1678 {
1679 	void *effective_key1, *effective_key2;
1680 	size_t effective_key1_len, effective_key2_len;
1681 	int ret;
1682 
1683 	if (lhs->is_max < rhs->is_max)
1684 		return -1;
1685 	if (lhs->is_max > rhs->is_max)
1686 		return 1;
1687 
1688 	if (lhs->pool < rhs->pool)
1689 		return -1;
1690 	if (lhs->pool > rhs->pool)
1691 		return 1;
1692 
1693 	if (hoid_get_bitwise_key(lhs) < hoid_get_bitwise_key(rhs))
1694 		return -1;
1695 	if (hoid_get_bitwise_key(lhs) > hoid_get_bitwise_key(rhs))
1696 		return 1;
1697 
1698 	ret = compare_names(lhs->nspace, lhs->nspace_len,
1699 			    rhs->nspace, rhs->nspace_len);
1700 	if (ret)
1701 		return ret;
1702 
1703 	hoid_get_effective_key(lhs, &effective_key1, &effective_key1_len);
1704 	hoid_get_effective_key(rhs, &effective_key2, &effective_key2_len);
1705 	ret = compare_names(effective_key1, effective_key1_len,
1706 			    effective_key2, effective_key2_len);
1707 	if (ret)
1708 		return ret;
1709 
1710 	ret = compare_names(lhs->oid, lhs->oid_len, rhs->oid, rhs->oid_len);
1711 	if (ret)
1712 		return ret;
1713 
1714 	if (lhs->snapid < rhs->snapid)
1715 		return -1;
1716 	if (lhs->snapid > rhs->snapid)
1717 		return 1;
1718 
1719 	return 0;
1720 }
1721 
1722 /*
1723  * For decoding ->begin and ->end of MOSDBackoff only -- no MIN/MAX
1724  * compat stuff here.
1725  *
1726  * Assumes @hoid is zero-initialized.
1727  */
1728 static int decode_hoid(void **p, void *end, struct ceph_hobject_id *hoid)
1729 {
1730 	u8 struct_v;
1731 	u32 struct_len;
1732 	int ret;
1733 
1734 	ret = ceph_start_decoding(p, end, 4, "hobject_t", &struct_v,
1735 				  &struct_len);
1736 	if (ret)
1737 		return ret;
1738 
1739 	if (struct_v < 4) {
1740 		pr_err("got struct_v %d < 4 of hobject_t\n", struct_v);
1741 		goto e_inval;
1742 	}
1743 
1744 	hoid->key = ceph_extract_encoded_string(p, end, &hoid->key_len,
1745 						GFP_NOIO);
1746 	if (IS_ERR(hoid->key)) {
1747 		ret = PTR_ERR(hoid->key);
1748 		hoid->key = NULL;
1749 		return ret;
1750 	}
1751 
1752 	hoid->oid = ceph_extract_encoded_string(p, end, &hoid->oid_len,
1753 						GFP_NOIO);
1754 	if (IS_ERR(hoid->oid)) {
1755 		ret = PTR_ERR(hoid->oid);
1756 		hoid->oid = NULL;
1757 		return ret;
1758 	}
1759 
1760 	ceph_decode_64_safe(p, end, hoid->snapid, e_inval);
1761 	ceph_decode_32_safe(p, end, hoid->hash, e_inval);
1762 	ceph_decode_8_safe(p, end, hoid->is_max, e_inval);
1763 
1764 	hoid->nspace = ceph_extract_encoded_string(p, end, &hoid->nspace_len,
1765 						   GFP_NOIO);
1766 	if (IS_ERR(hoid->nspace)) {
1767 		ret = PTR_ERR(hoid->nspace);
1768 		hoid->nspace = NULL;
1769 		return ret;
1770 	}
1771 
1772 	ceph_decode_64_safe(p, end, hoid->pool, e_inval);
1773 
1774 	ceph_hoid_build_hash_cache(hoid);
1775 	return 0;
1776 
1777 e_inval:
1778 	return -EINVAL;
1779 }
1780 
1781 static int hoid_encoding_size(const struct ceph_hobject_id *hoid)
1782 {
1783 	return 8 + 4 + 1 + 8 + /* snapid, hash, is_max, pool */
1784 	       4 + hoid->key_len + 4 + hoid->oid_len + 4 + hoid->nspace_len;
1785 }
1786 
1787 static void encode_hoid(void **p, void *end, const struct ceph_hobject_id *hoid)
1788 {
1789 	ceph_start_encoding(p, 4, 3, hoid_encoding_size(hoid));
1790 	ceph_encode_string(p, end, hoid->key, hoid->key_len);
1791 	ceph_encode_string(p, end, hoid->oid, hoid->oid_len);
1792 	ceph_encode_64(p, hoid->snapid);
1793 	ceph_encode_32(p, hoid->hash);
1794 	ceph_encode_8(p, hoid->is_max);
1795 	ceph_encode_string(p, end, hoid->nspace, hoid->nspace_len);
1796 	ceph_encode_64(p, hoid->pool);
1797 }
1798 
1799 static void free_hoid(struct ceph_hobject_id *hoid)
1800 {
1801 	if (hoid) {
1802 		kfree(hoid->key);
1803 		kfree(hoid->oid);
1804 		kfree(hoid->nspace);
1805 		kfree(hoid);
1806 	}
1807 }
1808 
1809 static struct ceph_osd_backoff *alloc_backoff(void)
1810 {
1811 	struct ceph_osd_backoff *backoff;
1812 
1813 	backoff = kzalloc(sizeof(*backoff), GFP_NOIO);
1814 	if (!backoff)
1815 		return NULL;
1816 
1817 	RB_CLEAR_NODE(&backoff->spg_node);
1818 	RB_CLEAR_NODE(&backoff->id_node);
1819 	return backoff;
1820 }
1821 
1822 static void free_backoff(struct ceph_osd_backoff *backoff)
1823 {
1824 	WARN_ON(!RB_EMPTY_NODE(&backoff->spg_node));
1825 	WARN_ON(!RB_EMPTY_NODE(&backoff->id_node));
1826 
1827 	free_hoid(backoff->begin);
1828 	free_hoid(backoff->end);
1829 	kfree(backoff);
1830 }
1831 
1832 /*
1833  * Within a specific spgid, backoffs are managed by ->begin hoid.
1834  */
1835 DEFINE_RB_INSDEL_FUNCS2(backoff, struct ceph_osd_backoff, begin, hoid_compare,
1836 			RB_BYVAL, spg_node);
1837 
1838 static struct ceph_osd_backoff *lookup_containing_backoff(struct rb_root *root,
1839 					    const struct ceph_hobject_id *hoid)
1840 {
1841 	struct rb_node *n = root->rb_node;
1842 
1843 	while (n) {
1844 		struct ceph_osd_backoff *cur =
1845 		    rb_entry(n, struct ceph_osd_backoff, spg_node);
1846 		int cmp;
1847 
1848 		cmp = hoid_compare(hoid, cur->begin);
1849 		if (cmp < 0) {
1850 			n = n->rb_left;
1851 		} else if (cmp > 0) {
1852 			if (hoid_compare(hoid, cur->end) < 0)
1853 				return cur;
1854 
1855 			n = n->rb_right;
1856 		} else {
1857 			return cur;
1858 		}
1859 	}
1860 
1861 	return NULL;
1862 }
1863 
1864 /*
1865  * Each backoff has a unique id within its OSD session.
1866  */
1867 DEFINE_RB_FUNCS(backoff_by_id, struct ceph_osd_backoff, id, id_node)
1868 
1869 static void clear_backoffs(struct ceph_osd *osd)
1870 {
1871 	while (!RB_EMPTY_ROOT(&osd->o_backoff_mappings)) {
1872 		struct ceph_spg_mapping *spg =
1873 		    rb_entry(rb_first(&osd->o_backoff_mappings),
1874 			     struct ceph_spg_mapping, node);
1875 
1876 		while (!RB_EMPTY_ROOT(&spg->backoffs)) {
1877 			struct ceph_osd_backoff *backoff =
1878 			    rb_entry(rb_first(&spg->backoffs),
1879 				     struct ceph_osd_backoff, spg_node);
1880 
1881 			erase_backoff(&spg->backoffs, backoff);
1882 			erase_backoff_by_id(&osd->o_backoffs_by_id, backoff);
1883 			free_backoff(backoff);
1884 		}
1885 		erase_spg_mapping(&osd->o_backoff_mappings, spg);
1886 		free_spg_mapping(spg);
1887 	}
1888 }
1889 
1890 /*
1891  * Set up a temporary, non-owning view into @t.
1892  */
1893 static void hoid_fill_from_target(struct ceph_hobject_id *hoid,
1894 				  const struct ceph_osd_request_target *t)
1895 {
1896 	hoid->key = NULL;
1897 	hoid->key_len = 0;
1898 	hoid->oid = t->target_oid.name;
1899 	hoid->oid_len = t->target_oid.name_len;
1900 	hoid->snapid = CEPH_NOSNAP;
1901 	hoid->hash = t->pgid.seed;
1902 	hoid->is_max = false;
1903 	if (t->target_oloc.pool_ns) {
1904 		hoid->nspace = t->target_oloc.pool_ns->str;
1905 		hoid->nspace_len = t->target_oloc.pool_ns->len;
1906 	} else {
1907 		hoid->nspace = NULL;
1908 		hoid->nspace_len = 0;
1909 	}
1910 	hoid->pool = t->target_oloc.pool;
1911 	ceph_hoid_build_hash_cache(hoid);
1912 }
1913 
1914 static bool should_plug_request(struct ceph_osd_request *req)
1915 {
1916 	struct ceph_osd *osd = req->r_osd;
1917 	struct ceph_spg_mapping *spg;
1918 	struct ceph_osd_backoff *backoff;
1919 	struct ceph_hobject_id hoid;
1920 
1921 	spg = lookup_spg_mapping(&osd->o_backoff_mappings, &req->r_t.spgid);
1922 	if (!spg)
1923 		return false;
1924 
1925 	hoid_fill_from_target(&hoid, &req->r_t);
1926 	backoff = lookup_containing_backoff(&spg->backoffs, &hoid);
1927 	if (!backoff)
1928 		return false;
1929 
1930 	dout("%s req %p tid %llu backoff osd%d spgid %llu.%xs%d id %llu\n",
1931 	     __func__, req, req->r_tid, osd->o_osd, backoff->spgid.pgid.pool,
1932 	     backoff->spgid.pgid.seed, backoff->spgid.shard, backoff->id);
1933 	return true;
1934 }
1935 
1936 /*
1937  * Keep get_num_data_items() in sync with this function.
1938  */
1939 static void setup_request_data(struct ceph_osd_request *req)
1940 {
1941 	struct ceph_msg *request_msg = req->r_request;
1942 	struct ceph_msg *reply_msg = req->r_reply;
1943 	struct ceph_osd_req_op *op;
1944 
1945 	if (req->r_request->num_data_items || req->r_reply->num_data_items)
1946 		return;
1947 
1948 	WARN_ON(request_msg->data_length || reply_msg->data_length);
1949 	for (op = req->r_ops; op != &req->r_ops[req->r_num_ops]; op++) {
1950 		switch (op->op) {
1951 		/* request */
1952 		case CEPH_OSD_OP_WRITE:
1953 		case CEPH_OSD_OP_WRITEFULL:
1954 			WARN_ON(op->indata_len != op->extent.length);
1955 			ceph_osdc_msg_data_add(request_msg,
1956 					       &op->extent.osd_data);
1957 			break;
1958 		case CEPH_OSD_OP_SETXATTR:
1959 		case CEPH_OSD_OP_CMPXATTR:
1960 			WARN_ON(op->indata_len != op->xattr.name_len +
1961 						  op->xattr.value_len);
1962 			ceph_osdc_msg_data_add(request_msg,
1963 					       &op->xattr.osd_data);
1964 			break;
1965 		case CEPH_OSD_OP_NOTIFY_ACK:
1966 			ceph_osdc_msg_data_add(request_msg,
1967 					       &op->notify_ack.request_data);
1968 			break;
1969 		case CEPH_OSD_OP_COPY_FROM2:
1970 			ceph_osdc_msg_data_add(request_msg,
1971 					       &op->copy_from.osd_data);
1972 			break;
1973 
1974 		/* reply */
1975 		case CEPH_OSD_OP_STAT:
1976 			ceph_osdc_msg_data_add(reply_msg,
1977 					       &op->raw_data_in);
1978 			break;
1979 		case CEPH_OSD_OP_READ:
1980 			ceph_osdc_msg_data_add(reply_msg,
1981 					       &op->extent.osd_data);
1982 			break;
1983 		case CEPH_OSD_OP_LIST_WATCHERS:
1984 			ceph_osdc_msg_data_add(reply_msg,
1985 					       &op->list_watchers.response_data);
1986 			break;
1987 
1988 		/* both */
1989 		case CEPH_OSD_OP_CALL:
1990 			WARN_ON(op->indata_len != op->cls.class_len +
1991 						  op->cls.method_len +
1992 						  op->cls.indata_len);
1993 			ceph_osdc_msg_data_add(request_msg,
1994 					       &op->cls.request_info);
1995 			/* optional, can be NONE */
1996 			ceph_osdc_msg_data_add(request_msg,
1997 					       &op->cls.request_data);
1998 			/* optional, can be NONE */
1999 			ceph_osdc_msg_data_add(reply_msg,
2000 					       &op->cls.response_data);
2001 			break;
2002 		case CEPH_OSD_OP_NOTIFY:
2003 			ceph_osdc_msg_data_add(request_msg,
2004 					       &op->notify.request_data);
2005 			ceph_osdc_msg_data_add(reply_msg,
2006 					       &op->notify.response_data);
2007 			break;
2008 		}
2009 	}
2010 }
2011 
2012 static void encode_pgid(void **p, const struct ceph_pg *pgid)
2013 {
2014 	ceph_encode_8(p, 1);
2015 	ceph_encode_64(p, pgid->pool);
2016 	ceph_encode_32(p, pgid->seed);
2017 	ceph_encode_32(p, -1); /* preferred */
2018 }
2019 
2020 static void encode_spgid(void **p, const struct ceph_spg *spgid)
2021 {
2022 	ceph_start_encoding(p, 1, 1, CEPH_PGID_ENCODING_LEN + 1);
2023 	encode_pgid(p, &spgid->pgid);
2024 	ceph_encode_8(p, spgid->shard);
2025 }
2026 
2027 static void encode_oloc(void **p, void *end,
2028 			const struct ceph_object_locator *oloc)
2029 {
2030 	ceph_start_encoding(p, 5, 4, ceph_oloc_encoding_size(oloc));
2031 	ceph_encode_64(p, oloc->pool);
2032 	ceph_encode_32(p, -1); /* preferred */
2033 	ceph_encode_32(p, 0);  /* key len */
2034 	if (oloc->pool_ns)
2035 		ceph_encode_string(p, end, oloc->pool_ns->str,
2036 				   oloc->pool_ns->len);
2037 	else
2038 		ceph_encode_32(p, 0);
2039 }
2040 
2041 static void encode_request_partial(struct ceph_osd_request *req,
2042 				   struct ceph_msg *msg)
2043 {
2044 	void *p = msg->front.iov_base;
2045 	void *const end = p + msg->front_alloc_len;
2046 	u32 data_len = 0;
2047 	int i;
2048 
2049 	if (req->r_flags & CEPH_OSD_FLAG_WRITE) {
2050 		/* snapshots aren't writeable */
2051 		WARN_ON(req->r_snapid != CEPH_NOSNAP);
2052 	} else {
2053 		WARN_ON(req->r_mtime.tv_sec || req->r_mtime.tv_nsec ||
2054 			req->r_data_offset || req->r_snapc);
2055 	}
2056 
2057 	setup_request_data(req);
2058 
2059 	encode_spgid(&p, &req->r_t.spgid); /* actual spg */
2060 	ceph_encode_32(&p, req->r_t.pgid.seed); /* raw hash */
2061 	ceph_encode_32(&p, req->r_osdc->osdmap->epoch);
2062 	ceph_encode_32(&p, req->r_flags);
2063 
2064 	/* reqid */
2065 	ceph_start_encoding(&p, 2, 2, sizeof(struct ceph_osd_reqid));
2066 	memset(p, 0, sizeof(struct ceph_osd_reqid));
2067 	p += sizeof(struct ceph_osd_reqid);
2068 
2069 	/* trace */
2070 	memset(p, 0, sizeof(struct ceph_blkin_trace_info));
2071 	p += sizeof(struct ceph_blkin_trace_info);
2072 
2073 	ceph_encode_32(&p, 0); /* client_inc, always 0 */
2074 	ceph_encode_timespec64(p, &req->r_mtime);
2075 	p += sizeof(struct ceph_timespec);
2076 
2077 	encode_oloc(&p, end, &req->r_t.target_oloc);
2078 	ceph_encode_string(&p, end, req->r_t.target_oid.name,
2079 			   req->r_t.target_oid.name_len);
2080 
2081 	/* ops, can imply data */
2082 	ceph_encode_16(&p, req->r_num_ops);
2083 	for (i = 0; i < req->r_num_ops; i++) {
2084 		data_len += osd_req_encode_op(p, &req->r_ops[i]);
2085 		p += sizeof(struct ceph_osd_op);
2086 	}
2087 
2088 	ceph_encode_64(&p, req->r_snapid); /* snapid */
2089 	if (req->r_snapc) {
2090 		ceph_encode_64(&p, req->r_snapc->seq);
2091 		ceph_encode_32(&p, req->r_snapc->num_snaps);
2092 		for (i = 0; i < req->r_snapc->num_snaps; i++)
2093 			ceph_encode_64(&p, req->r_snapc->snaps[i]);
2094 	} else {
2095 		ceph_encode_64(&p, 0); /* snap_seq */
2096 		ceph_encode_32(&p, 0); /* snaps len */
2097 	}
2098 
2099 	ceph_encode_32(&p, req->r_attempts); /* retry_attempt */
2100 	BUG_ON(p > end - 8); /* space for features */
2101 
2102 	msg->hdr.version = cpu_to_le16(8); /* MOSDOp v8 */
2103 	/* front_len is finalized in encode_request_finish() */
2104 	msg->front.iov_len = p - msg->front.iov_base;
2105 	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
2106 	msg->hdr.data_len = cpu_to_le32(data_len);
2107 	/*
2108 	 * The header "data_off" is a hint to the receiver allowing it
2109 	 * to align received data into its buffers such that there's no
2110 	 * need to re-copy it before writing it to disk (direct I/O).
2111 	 */
2112 	msg->hdr.data_off = cpu_to_le16(req->r_data_offset);
2113 
2114 	dout("%s req %p msg %p oid %s oid_len %d\n", __func__, req, msg,
2115 	     req->r_t.target_oid.name, req->r_t.target_oid.name_len);
2116 }
2117 
2118 static void encode_request_finish(struct ceph_msg *msg)
2119 {
2120 	void *p = msg->front.iov_base;
2121 	void *const partial_end = p + msg->front.iov_len;
2122 	void *const end = p + msg->front_alloc_len;
2123 
2124 	if (CEPH_HAVE_FEATURE(msg->con->peer_features, RESEND_ON_SPLIT)) {
2125 		/* luminous OSD -- encode features and be done */
2126 		p = partial_end;
2127 		ceph_encode_64(&p, msg->con->peer_features);
2128 	} else {
2129 		struct {
2130 			char spgid[CEPH_ENCODING_START_BLK_LEN +
2131 				   CEPH_PGID_ENCODING_LEN + 1];
2132 			__le32 hash;
2133 			__le32 epoch;
2134 			__le32 flags;
2135 			char reqid[CEPH_ENCODING_START_BLK_LEN +
2136 				   sizeof(struct ceph_osd_reqid)];
2137 			char trace[sizeof(struct ceph_blkin_trace_info)];
2138 			__le32 client_inc;
2139 			struct ceph_timespec mtime;
2140 		} __packed head;
2141 		struct ceph_pg pgid;
2142 		void *oloc, *oid, *tail;
2143 		int oloc_len, oid_len, tail_len;
2144 		int len;
2145 
2146 		/*
2147 		 * Pre-luminous OSD -- reencode v8 into v4 using @head
2148 		 * as a temporary buffer.  Encode the raw PG; the rest
2149 		 * is just a matter of moving oloc, oid and tail blobs
2150 		 * around.
2151 		 */
2152 		memcpy(&head, p, sizeof(head));
2153 		p += sizeof(head);
2154 
2155 		oloc = p;
2156 		p += CEPH_ENCODING_START_BLK_LEN;
2157 		pgid.pool = ceph_decode_64(&p);
2158 		p += 4 + 4; /* preferred, key len */
2159 		len = ceph_decode_32(&p);
2160 		p += len;   /* nspace */
2161 		oloc_len = p - oloc;
2162 
2163 		oid = p;
2164 		len = ceph_decode_32(&p);
2165 		p += len;
2166 		oid_len = p - oid;
2167 
2168 		tail = p;
2169 		tail_len = partial_end - p;
2170 
2171 		p = msg->front.iov_base;
2172 		ceph_encode_copy(&p, &head.client_inc, sizeof(head.client_inc));
2173 		ceph_encode_copy(&p, &head.epoch, sizeof(head.epoch));
2174 		ceph_encode_copy(&p, &head.flags, sizeof(head.flags));
2175 		ceph_encode_copy(&p, &head.mtime, sizeof(head.mtime));
2176 
2177 		/* reassert_version */
2178 		memset(p, 0, sizeof(struct ceph_eversion));
2179 		p += sizeof(struct ceph_eversion);
2180 
2181 		BUG_ON(p >= oloc);
2182 		memmove(p, oloc, oloc_len);
2183 		p += oloc_len;
2184 
2185 		pgid.seed = le32_to_cpu(head.hash);
2186 		encode_pgid(&p, &pgid); /* raw pg */
2187 
2188 		BUG_ON(p >= oid);
2189 		memmove(p, oid, oid_len);
2190 		p += oid_len;
2191 
2192 		/* tail -- ops, snapid, snapc, retry_attempt */
2193 		BUG_ON(p >= tail);
2194 		memmove(p, tail, tail_len);
2195 		p += tail_len;
2196 
2197 		msg->hdr.version = cpu_to_le16(4); /* MOSDOp v4 */
2198 	}
2199 
2200 	BUG_ON(p > end);
2201 	msg->front.iov_len = p - msg->front.iov_base;
2202 	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
2203 
2204 	dout("%s msg %p tid %llu %u+%u+%u v%d\n", __func__, msg,
2205 	     le64_to_cpu(msg->hdr.tid), le32_to_cpu(msg->hdr.front_len),
2206 	     le32_to_cpu(msg->hdr.middle_len), le32_to_cpu(msg->hdr.data_len),
2207 	     le16_to_cpu(msg->hdr.version));
2208 }
2209 
2210 /*
2211  * @req has to be assigned a tid and registered.
2212  */
2213 static void send_request(struct ceph_osd_request *req)
2214 {
2215 	struct ceph_osd *osd = req->r_osd;
2216 
2217 	verify_osd_locked(osd);
2218 	WARN_ON(osd->o_osd != req->r_t.osd);
2219 
2220 	/* backoff? */
2221 	if (should_plug_request(req))
2222 		return;
2223 
2224 	/*
2225 	 * We may have a previously queued request message hanging
2226 	 * around.  Cancel it to avoid corrupting the msgr.
2227 	 */
2228 	if (req->r_sent)
2229 		ceph_msg_revoke(req->r_request);
2230 
2231 	req->r_flags |= CEPH_OSD_FLAG_KNOWN_REDIR;
2232 	if (req->r_attempts)
2233 		req->r_flags |= CEPH_OSD_FLAG_RETRY;
2234 	else
2235 		WARN_ON(req->r_flags & CEPH_OSD_FLAG_RETRY);
2236 
2237 	encode_request_partial(req, req->r_request);
2238 
2239 	dout("%s req %p tid %llu to pgid %llu.%x spgid %llu.%xs%d osd%d e%u flags 0x%x attempt %d\n",
2240 	     __func__, req, req->r_tid, req->r_t.pgid.pool, req->r_t.pgid.seed,
2241 	     req->r_t.spgid.pgid.pool, req->r_t.spgid.pgid.seed,
2242 	     req->r_t.spgid.shard, osd->o_osd, req->r_t.epoch, req->r_flags,
2243 	     req->r_attempts);
2244 
2245 	req->r_t.paused = false;
2246 	req->r_stamp = jiffies;
2247 	req->r_attempts++;
2248 
2249 	req->r_sent = osd->o_incarnation;
2250 	req->r_request->hdr.tid = cpu_to_le64(req->r_tid);
2251 	ceph_con_send(&osd->o_con, ceph_msg_get(req->r_request));
2252 }
2253 
2254 static void maybe_request_map(struct ceph_osd_client *osdc)
2255 {
2256 	bool continuous = false;
2257 
2258 	verify_osdc_locked(osdc);
2259 	WARN_ON(!osdc->osdmap->epoch);
2260 
2261 	if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
2262 	    ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD) ||
2263 	    ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR)) {
2264 		dout("%s osdc %p continuous\n", __func__, osdc);
2265 		continuous = true;
2266 	} else {
2267 		dout("%s osdc %p onetime\n", __func__, osdc);
2268 	}
2269 
2270 	if (ceph_monc_want_map(&osdc->client->monc, CEPH_SUB_OSDMAP,
2271 			       osdc->osdmap->epoch + 1, continuous))
2272 		ceph_monc_renew_subs(&osdc->client->monc);
2273 }
2274 
2275 static void complete_request(struct ceph_osd_request *req, int err);
2276 static void send_map_check(struct ceph_osd_request *req);
2277 
2278 static void __submit_request(struct ceph_osd_request *req, bool wrlocked)
2279 {
2280 	struct ceph_osd_client *osdc = req->r_osdc;
2281 	struct ceph_osd *osd;
2282 	enum calc_target_result ct_res;
2283 	int err = 0;
2284 	bool need_send = false;
2285 	bool promoted = false;
2286 
2287 	WARN_ON(req->r_tid);
2288 	dout("%s req %p wrlocked %d\n", __func__, req, wrlocked);
2289 
2290 again:
2291 	ct_res = calc_target(osdc, &req->r_t, false);
2292 	if (ct_res == CALC_TARGET_POOL_DNE && !wrlocked)
2293 		goto promote;
2294 
2295 	osd = lookup_create_osd(osdc, req->r_t.osd, wrlocked);
2296 	if (IS_ERR(osd)) {
2297 		WARN_ON(PTR_ERR(osd) != -EAGAIN || wrlocked);
2298 		goto promote;
2299 	}
2300 
2301 	if (osdc->abort_err) {
2302 		dout("req %p abort_err %d\n", req, osdc->abort_err);
2303 		err = osdc->abort_err;
2304 	} else if (osdc->osdmap->epoch < osdc->epoch_barrier) {
2305 		dout("req %p epoch %u barrier %u\n", req, osdc->osdmap->epoch,
2306 		     osdc->epoch_barrier);
2307 		req->r_t.paused = true;
2308 		maybe_request_map(osdc);
2309 	} else if ((req->r_flags & CEPH_OSD_FLAG_WRITE) &&
2310 		   ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR)) {
2311 		dout("req %p pausewr\n", req);
2312 		req->r_t.paused = true;
2313 		maybe_request_map(osdc);
2314 	} else if ((req->r_flags & CEPH_OSD_FLAG_READ) &&
2315 		   ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD)) {
2316 		dout("req %p pauserd\n", req);
2317 		req->r_t.paused = true;
2318 		maybe_request_map(osdc);
2319 	} else if ((req->r_flags & CEPH_OSD_FLAG_WRITE) &&
2320 		   !(req->r_flags & (CEPH_OSD_FLAG_FULL_TRY |
2321 				     CEPH_OSD_FLAG_FULL_FORCE)) &&
2322 		   (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
2323 		    pool_full(osdc, req->r_t.base_oloc.pool))) {
2324 		dout("req %p full/pool_full\n", req);
2325 		if (ceph_test_opt(osdc->client, ABORT_ON_FULL)) {
2326 			err = -ENOSPC;
2327 		} else {
2328 			pr_warn_ratelimited("FULL or reached pool quota\n");
2329 			req->r_t.paused = true;
2330 			maybe_request_map(osdc);
2331 		}
2332 	} else if (!osd_homeless(osd)) {
2333 		need_send = true;
2334 	} else {
2335 		maybe_request_map(osdc);
2336 	}
2337 
2338 	mutex_lock(&osd->lock);
2339 	/*
2340 	 * Assign the tid atomically with send_request() to protect
2341 	 * multiple writes to the same object from racing with each
2342 	 * other, resulting in out of order ops on the OSDs.
2343 	 */
2344 	req->r_tid = atomic64_inc_return(&osdc->last_tid);
2345 	link_request(osd, req);
2346 	if (need_send)
2347 		send_request(req);
2348 	else if (err)
2349 		complete_request(req, err);
2350 	mutex_unlock(&osd->lock);
2351 
2352 	if (!err && ct_res == CALC_TARGET_POOL_DNE)
2353 		send_map_check(req);
2354 
2355 	if (promoted)
2356 		downgrade_write(&osdc->lock);
2357 	return;
2358 
2359 promote:
2360 	up_read(&osdc->lock);
2361 	down_write(&osdc->lock);
2362 	wrlocked = true;
2363 	promoted = true;
2364 	goto again;
2365 }
2366 
2367 static void account_request(struct ceph_osd_request *req)
2368 {
2369 	WARN_ON(req->r_flags & (CEPH_OSD_FLAG_ACK | CEPH_OSD_FLAG_ONDISK));
2370 	WARN_ON(!(req->r_flags & (CEPH_OSD_FLAG_READ | CEPH_OSD_FLAG_WRITE)));
2371 
2372 	req->r_flags |= CEPH_OSD_FLAG_ONDISK;
2373 	atomic_inc(&req->r_osdc->num_requests);
2374 
2375 	req->r_start_stamp = jiffies;
2376 }
2377 
2378 static void submit_request(struct ceph_osd_request *req, bool wrlocked)
2379 {
2380 	ceph_osdc_get_request(req);
2381 	account_request(req);
2382 	__submit_request(req, wrlocked);
2383 }
2384 
2385 static void finish_request(struct ceph_osd_request *req)
2386 {
2387 	struct ceph_osd_client *osdc = req->r_osdc;
2388 
2389 	WARN_ON(lookup_request_mc(&osdc->map_checks, req->r_tid));
2390 	dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
2391 
2392 	if (req->r_osd)
2393 		unlink_request(req->r_osd, req);
2394 	atomic_dec(&osdc->num_requests);
2395 
2396 	/*
2397 	 * If an OSD has failed or returned and a request has been sent
2398 	 * twice, it's possible to get a reply and end up here while the
2399 	 * request message is queued for delivery.  We will ignore the
2400 	 * reply, so not a big deal, but better to try and catch it.
2401 	 */
2402 	ceph_msg_revoke(req->r_request);
2403 	ceph_msg_revoke_incoming(req->r_reply);
2404 }
2405 
2406 static void __complete_request(struct ceph_osd_request *req)
2407 {
2408 	dout("%s req %p tid %llu cb %ps result %d\n", __func__, req,
2409 	     req->r_tid, req->r_callback, req->r_result);
2410 
2411 	if (req->r_callback)
2412 		req->r_callback(req);
2413 	complete_all(&req->r_completion);
2414 	ceph_osdc_put_request(req);
2415 }
2416 
2417 static void complete_request_workfn(struct work_struct *work)
2418 {
2419 	struct ceph_osd_request *req =
2420 	    container_of(work, struct ceph_osd_request, r_complete_work);
2421 
2422 	__complete_request(req);
2423 }
2424 
2425 /*
2426  * This is open-coded in handle_reply().
2427  */
2428 static void complete_request(struct ceph_osd_request *req, int err)
2429 {
2430 	dout("%s req %p tid %llu err %d\n", __func__, req, req->r_tid, err);
2431 
2432 	req->r_result = err;
2433 	finish_request(req);
2434 
2435 	INIT_WORK(&req->r_complete_work, complete_request_workfn);
2436 	queue_work(req->r_osdc->completion_wq, &req->r_complete_work);
2437 }
2438 
2439 static void cancel_map_check(struct ceph_osd_request *req)
2440 {
2441 	struct ceph_osd_client *osdc = req->r_osdc;
2442 	struct ceph_osd_request *lookup_req;
2443 
2444 	verify_osdc_wrlocked(osdc);
2445 
2446 	lookup_req = lookup_request_mc(&osdc->map_checks, req->r_tid);
2447 	if (!lookup_req)
2448 		return;
2449 
2450 	WARN_ON(lookup_req != req);
2451 	erase_request_mc(&osdc->map_checks, req);
2452 	ceph_osdc_put_request(req);
2453 }
2454 
2455 static void cancel_request(struct ceph_osd_request *req)
2456 {
2457 	dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
2458 
2459 	cancel_map_check(req);
2460 	finish_request(req);
2461 	complete_all(&req->r_completion);
2462 	ceph_osdc_put_request(req);
2463 }
2464 
2465 static void abort_request(struct ceph_osd_request *req, int err)
2466 {
2467 	dout("%s req %p tid %llu err %d\n", __func__, req, req->r_tid, err);
2468 
2469 	cancel_map_check(req);
2470 	complete_request(req, err);
2471 }
2472 
2473 static int abort_fn(struct ceph_osd_request *req, void *arg)
2474 {
2475 	int err = *(int *)arg;
2476 
2477 	abort_request(req, err);
2478 	return 0; /* continue iteration */
2479 }
2480 
2481 /*
2482  * Abort all in-flight requests with @err and arrange for all future
2483  * requests to be failed immediately.
2484  */
2485 void ceph_osdc_abort_requests(struct ceph_osd_client *osdc, int err)
2486 {
2487 	dout("%s osdc %p err %d\n", __func__, osdc, err);
2488 	down_write(&osdc->lock);
2489 	for_each_request(osdc, abort_fn, &err);
2490 	osdc->abort_err = err;
2491 	up_write(&osdc->lock);
2492 }
2493 EXPORT_SYMBOL(ceph_osdc_abort_requests);
2494 
2495 void ceph_osdc_clear_abort_err(struct ceph_osd_client *osdc)
2496 {
2497 	down_write(&osdc->lock);
2498 	osdc->abort_err = 0;
2499 	up_write(&osdc->lock);
2500 }
2501 EXPORT_SYMBOL(ceph_osdc_clear_abort_err);
2502 
2503 static void update_epoch_barrier(struct ceph_osd_client *osdc, u32 eb)
2504 {
2505 	if (likely(eb > osdc->epoch_barrier)) {
2506 		dout("updating epoch_barrier from %u to %u\n",
2507 				osdc->epoch_barrier, eb);
2508 		osdc->epoch_barrier = eb;
2509 		/* Request map if we're not to the barrier yet */
2510 		if (eb > osdc->osdmap->epoch)
2511 			maybe_request_map(osdc);
2512 	}
2513 }
2514 
2515 void ceph_osdc_update_epoch_barrier(struct ceph_osd_client *osdc, u32 eb)
2516 {
2517 	down_read(&osdc->lock);
2518 	if (unlikely(eb > osdc->epoch_barrier)) {
2519 		up_read(&osdc->lock);
2520 		down_write(&osdc->lock);
2521 		update_epoch_barrier(osdc, eb);
2522 		up_write(&osdc->lock);
2523 	} else {
2524 		up_read(&osdc->lock);
2525 	}
2526 }
2527 EXPORT_SYMBOL(ceph_osdc_update_epoch_barrier);
2528 
2529 /*
2530  * We can end up releasing caps as a result of abort_request().
2531  * In that case, we probably want to ensure that the cap release message
2532  * has an updated epoch barrier in it, so set the epoch barrier prior to
2533  * aborting the first request.
2534  */
2535 static int abort_on_full_fn(struct ceph_osd_request *req, void *arg)
2536 {
2537 	struct ceph_osd_client *osdc = req->r_osdc;
2538 	bool *victims = arg;
2539 
2540 	if ((req->r_flags & CEPH_OSD_FLAG_WRITE) &&
2541 	    (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
2542 	     pool_full(osdc, req->r_t.base_oloc.pool))) {
2543 		if (!*victims) {
2544 			update_epoch_barrier(osdc, osdc->osdmap->epoch);
2545 			*victims = true;
2546 		}
2547 		abort_request(req, -ENOSPC);
2548 	}
2549 
2550 	return 0; /* continue iteration */
2551 }
2552 
2553 /*
2554  * Drop all pending requests that are stalled waiting on a full condition to
2555  * clear, and complete them with ENOSPC as the return code. Set the
2556  * osdc->epoch_barrier to the latest map epoch that we've seen if any were
2557  * cancelled.
2558  */
2559 static void ceph_osdc_abort_on_full(struct ceph_osd_client *osdc)
2560 {
2561 	bool victims = false;
2562 
2563 	if (ceph_test_opt(osdc->client, ABORT_ON_FULL) &&
2564 	    (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) || have_pool_full(osdc)))
2565 		for_each_request(osdc, abort_on_full_fn, &victims);
2566 }
2567 
2568 static void check_pool_dne(struct ceph_osd_request *req)
2569 {
2570 	struct ceph_osd_client *osdc = req->r_osdc;
2571 	struct ceph_osdmap *map = osdc->osdmap;
2572 
2573 	verify_osdc_wrlocked(osdc);
2574 	WARN_ON(!map->epoch);
2575 
2576 	if (req->r_attempts) {
2577 		/*
2578 		 * We sent a request earlier, which means that
2579 		 * previously the pool existed, and now it does not
2580 		 * (i.e., it was deleted).
2581 		 */
2582 		req->r_map_dne_bound = map->epoch;
2583 		dout("%s req %p tid %llu pool disappeared\n", __func__, req,
2584 		     req->r_tid);
2585 	} else {
2586 		dout("%s req %p tid %llu map_dne_bound %u have %u\n", __func__,
2587 		     req, req->r_tid, req->r_map_dne_bound, map->epoch);
2588 	}
2589 
2590 	if (req->r_map_dne_bound) {
2591 		if (map->epoch >= req->r_map_dne_bound) {
2592 			/* we had a new enough map */
2593 			pr_info_ratelimited("tid %llu pool does not exist\n",
2594 					    req->r_tid);
2595 			complete_request(req, -ENOENT);
2596 		}
2597 	} else {
2598 		send_map_check(req);
2599 	}
2600 }
2601 
2602 static void map_check_cb(struct ceph_mon_generic_request *greq)
2603 {
2604 	struct ceph_osd_client *osdc = &greq->monc->client->osdc;
2605 	struct ceph_osd_request *req;
2606 	u64 tid = greq->private_data;
2607 
2608 	WARN_ON(greq->result || !greq->u.newest);
2609 
2610 	down_write(&osdc->lock);
2611 	req = lookup_request_mc(&osdc->map_checks, tid);
2612 	if (!req) {
2613 		dout("%s tid %llu dne\n", __func__, tid);
2614 		goto out_unlock;
2615 	}
2616 
2617 	dout("%s req %p tid %llu map_dne_bound %u newest %llu\n", __func__,
2618 	     req, req->r_tid, req->r_map_dne_bound, greq->u.newest);
2619 	if (!req->r_map_dne_bound)
2620 		req->r_map_dne_bound = greq->u.newest;
2621 	erase_request_mc(&osdc->map_checks, req);
2622 	check_pool_dne(req);
2623 
2624 	ceph_osdc_put_request(req);
2625 out_unlock:
2626 	up_write(&osdc->lock);
2627 }
2628 
2629 static void send_map_check(struct ceph_osd_request *req)
2630 {
2631 	struct ceph_osd_client *osdc = req->r_osdc;
2632 	struct ceph_osd_request *lookup_req;
2633 	int ret;
2634 
2635 	verify_osdc_wrlocked(osdc);
2636 
2637 	lookup_req = lookup_request_mc(&osdc->map_checks, req->r_tid);
2638 	if (lookup_req) {
2639 		WARN_ON(lookup_req != req);
2640 		return;
2641 	}
2642 
2643 	ceph_osdc_get_request(req);
2644 	insert_request_mc(&osdc->map_checks, req);
2645 	ret = ceph_monc_get_version_async(&osdc->client->monc, "osdmap",
2646 					  map_check_cb, req->r_tid);
2647 	WARN_ON(ret);
2648 }
2649 
2650 /*
2651  * lingering requests, watch/notify v2 infrastructure
2652  */
2653 static void linger_release(struct kref *kref)
2654 {
2655 	struct ceph_osd_linger_request *lreq =
2656 	    container_of(kref, struct ceph_osd_linger_request, kref);
2657 
2658 	dout("%s lreq %p reg_req %p ping_req %p\n", __func__, lreq,
2659 	     lreq->reg_req, lreq->ping_req);
2660 	WARN_ON(!RB_EMPTY_NODE(&lreq->node));
2661 	WARN_ON(!RB_EMPTY_NODE(&lreq->osdc_node));
2662 	WARN_ON(!RB_EMPTY_NODE(&lreq->mc_node));
2663 	WARN_ON(!list_empty(&lreq->scan_item));
2664 	WARN_ON(!list_empty(&lreq->pending_lworks));
2665 	WARN_ON(lreq->osd);
2666 
2667 	if (lreq->reg_req)
2668 		ceph_osdc_put_request(lreq->reg_req);
2669 	if (lreq->ping_req)
2670 		ceph_osdc_put_request(lreq->ping_req);
2671 	target_destroy(&lreq->t);
2672 	kfree(lreq);
2673 }
2674 
2675 static void linger_put(struct ceph_osd_linger_request *lreq)
2676 {
2677 	if (lreq)
2678 		kref_put(&lreq->kref, linger_release);
2679 }
2680 
2681 static struct ceph_osd_linger_request *
2682 linger_get(struct ceph_osd_linger_request *lreq)
2683 {
2684 	kref_get(&lreq->kref);
2685 	return lreq;
2686 }
2687 
2688 static struct ceph_osd_linger_request *
2689 linger_alloc(struct ceph_osd_client *osdc)
2690 {
2691 	struct ceph_osd_linger_request *lreq;
2692 
2693 	lreq = kzalloc(sizeof(*lreq), GFP_NOIO);
2694 	if (!lreq)
2695 		return NULL;
2696 
2697 	kref_init(&lreq->kref);
2698 	mutex_init(&lreq->lock);
2699 	RB_CLEAR_NODE(&lreq->node);
2700 	RB_CLEAR_NODE(&lreq->osdc_node);
2701 	RB_CLEAR_NODE(&lreq->mc_node);
2702 	INIT_LIST_HEAD(&lreq->scan_item);
2703 	INIT_LIST_HEAD(&lreq->pending_lworks);
2704 	init_completion(&lreq->reg_commit_wait);
2705 	init_completion(&lreq->notify_finish_wait);
2706 
2707 	lreq->osdc = osdc;
2708 	target_init(&lreq->t);
2709 
2710 	dout("%s lreq %p\n", __func__, lreq);
2711 	return lreq;
2712 }
2713 
2714 DEFINE_RB_INSDEL_FUNCS(linger, struct ceph_osd_linger_request, linger_id, node)
2715 DEFINE_RB_FUNCS(linger_osdc, struct ceph_osd_linger_request, linger_id, osdc_node)
2716 DEFINE_RB_FUNCS(linger_mc, struct ceph_osd_linger_request, linger_id, mc_node)
2717 
2718 /*
2719  * Create linger request <-> OSD session relation.
2720  *
2721  * @lreq has to be registered, @osd may be homeless.
2722  */
2723 static void link_linger(struct ceph_osd *osd,
2724 			struct ceph_osd_linger_request *lreq)
2725 {
2726 	verify_osd_locked(osd);
2727 	WARN_ON(!lreq->linger_id || lreq->osd);
2728 	dout("%s osd %p osd%d lreq %p linger_id %llu\n", __func__, osd,
2729 	     osd->o_osd, lreq, lreq->linger_id);
2730 
2731 	if (!osd_homeless(osd))
2732 		__remove_osd_from_lru(osd);
2733 	else
2734 		atomic_inc(&osd->o_osdc->num_homeless);
2735 
2736 	get_osd(osd);
2737 	insert_linger(&osd->o_linger_requests, lreq);
2738 	lreq->osd = osd;
2739 }
2740 
2741 static void unlink_linger(struct ceph_osd *osd,
2742 			  struct ceph_osd_linger_request *lreq)
2743 {
2744 	verify_osd_locked(osd);
2745 	WARN_ON(lreq->osd != osd);
2746 	dout("%s osd %p osd%d lreq %p linger_id %llu\n", __func__, osd,
2747 	     osd->o_osd, lreq, lreq->linger_id);
2748 
2749 	lreq->osd = NULL;
2750 	erase_linger(&osd->o_linger_requests, lreq);
2751 	put_osd(osd);
2752 
2753 	if (!osd_homeless(osd))
2754 		maybe_move_osd_to_lru(osd);
2755 	else
2756 		atomic_dec(&osd->o_osdc->num_homeless);
2757 }
2758 
2759 static bool __linger_registered(struct ceph_osd_linger_request *lreq)
2760 {
2761 	verify_osdc_locked(lreq->osdc);
2762 
2763 	return !RB_EMPTY_NODE(&lreq->osdc_node);
2764 }
2765 
2766 static bool linger_registered(struct ceph_osd_linger_request *lreq)
2767 {
2768 	struct ceph_osd_client *osdc = lreq->osdc;
2769 	bool registered;
2770 
2771 	down_read(&osdc->lock);
2772 	registered = __linger_registered(lreq);
2773 	up_read(&osdc->lock);
2774 
2775 	return registered;
2776 }
2777 
2778 static void linger_register(struct ceph_osd_linger_request *lreq)
2779 {
2780 	struct ceph_osd_client *osdc = lreq->osdc;
2781 
2782 	verify_osdc_wrlocked(osdc);
2783 	WARN_ON(lreq->linger_id);
2784 
2785 	linger_get(lreq);
2786 	lreq->linger_id = ++osdc->last_linger_id;
2787 	insert_linger_osdc(&osdc->linger_requests, lreq);
2788 }
2789 
2790 static void linger_unregister(struct ceph_osd_linger_request *lreq)
2791 {
2792 	struct ceph_osd_client *osdc = lreq->osdc;
2793 
2794 	verify_osdc_wrlocked(osdc);
2795 
2796 	erase_linger_osdc(&osdc->linger_requests, lreq);
2797 	linger_put(lreq);
2798 }
2799 
2800 static void cancel_linger_request(struct ceph_osd_request *req)
2801 {
2802 	struct ceph_osd_linger_request *lreq = req->r_priv;
2803 
2804 	WARN_ON(!req->r_linger);
2805 	cancel_request(req);
2806 	linger_put(lreq);
2807 }
2808 
2809 struct linger_work {
2810 	struct work_struct work;
2811 	struct ceph_osd_linger_request *lreq;
2812 	struct list_head pending_item;
2813 	unsigned long queued_stamp;
2814 
2815 	union {
2816 		struct {
2817 			u64 notify_id;
2818 			u64 notifier_id;
2819 			void *payload; /* points into @msg front */
2820 			size_t payload_len;
2821 
2822 			struct ceph_msg *msg; /* for ceph_msg_put() */
2823 		} notify;
2824 		struct {
2825 			int err;
2826 		} error;
2827 	};
2828 };
2829 
2830 static struct linger_work *lwork_alloc(struct ceph_osd_linger_request *lreq,
2831 				       work_func_t workfn)
2832 {
2833 	struct linger_work *lwork;
2834 
2835 	lwork = kzalloc(sizeof(*lwork), GFP_NOIO);
2836 	if (!lwork)
2837 		return NULL;
2838 
2839 	INIT_WORK(&lwork->work, workfn);
2840 	INIT_LIST_HEAD(&lwork->pending_item);
2841 	lwork->lreq = linger_get(lreq);
2842 
2843 	return lwork;
2844 }
2845 
2846 static void lwork_free(struct linger_work *lwork)
2847 {
2848 	struct ceph_osd_linger_request *lreq = lwork->lreq;
2849 
2850 	mutex_lock(&lreq->lock);
2851 	list_del(&lwork->pending_item);
2852 	mutex_unlock(&lreq->lock);
2853 
2854 	linger_put(lreq);
2855 	kfree(lwork);
2856 }
2857 
2858 static void lwork_queue(struct linger_work *lwork)
2859 {
2860 	struct ceph_osd_linger_request *lreq = lwork->lreq;
2861 	struct ceph_osd_client *osdc = lreq->osdc;
2862 
2863 	verify_lreq_locked(lreq);
2864 	WARN_ON(!list_empty(&lwork->pending_item));
2865 
2866 	lwork->queued_stamp = jiffies;
2867 	list_add_tail(&lwork->pending_item, &lreq->pending_lworks);
2868 	queue_work(osdc->notify_wq, &lwork->work);
2869 }
2870 
2871 static void do_watch_notify(struct work_struct *w)
2872 {
2873 	struct linger_work *lwork = container_of(w, struct linger_work, work);
2874 	struct ceph_osd_linger_request *lreq = lwork->lreq;
2875 
2876 	if (!linger_registered(lreq)) {
2877 		dout("%s lreq %p not registered\n", __func__, lreq);
2878 		goto out;
2879 	}
2880 
2881 	WARN_ON(!lreq->is_watch);
2882 	dout("%s lreq %p notify_id %llu notifier_id %llu payload_len %zu\n",
2883 	     __func__, lreq, lwork->notify.notify_id, lwork->notify.notifier_id,
2884 	     lwork->notify.payload_len);
2885 	lreq->wcb(lreq->data, lwork->notify.notify_id, lreq->linger_id,
2886 		  lwork->notify.notifier_id, lwork->notify.payload,
2887 		  lwork->notify.payload_len);
2888 
2889 out:
2890 	ceph_msg_put(lwork->notify.msg);
2891 	lwork_free(lwork);
2892 }
2893 
2894 static void do_watch_error(struct work_struct *w)
2895 {
2896 	struct linger_work *lwork = container_of(w, struct linger_work, work);
2897 	struct ceph_osd_linger_request *lreq = lwork->lreq;
2898 
2899 	if (!linger_registered(lreq)) {
2900 		dout("%s lreq %p not registered\n", __func__, lreq);
2901 		goto out;
2902 	}
2903 
2904 	dout("%s lreq %p err %d\n", __func__, lreq, lwork->error.err);
2905 	lreq->errcb(lreq->data, lreq->linger_id, lwork->error.err);
2906 
2907 out:
2908 	lwork_free(lwork);
2909 }
2910 
2911 static void queue_watch_error(struct ceph_osd_linger_request *lreq)
2912 {
2913 	struct linger_work *lwork;
2914 
2915 	lwork = lwork_alloc(lreq, do_watch_error);
2916 	if (!lwork) {
2917 		pr_err("failed to allocate error-lwork\n");
2918 		return;
2919 	}
2920 
2921 	lwork->error.err = lreq->last_error;
2922 	lwork_queue(lwork);
2923 }
2924 
2925 static void linger_reg_commit_complete(struct ceph_osd_linger_request *lreq,
2926 				       int result)
2927 {
2928 	if (!completion_done(&lreq->reg_commit_wait)) {
2929 		lreq->reg_commit_error = (result <= 0 ? result : 0);
2930 		complete_all(&lreq->reg_commit_wait);
2931 	}
2932 }
2933 
2934 static void linger_commit_cb(struct ceph_osd_request *req)
2935 {
2936 	struct ceph_osd_linger_request *lreq = req->r_priv;
2937 
2938 	mutex_lock(&lreq->lock);
2939 	dout("%s lreq %p linger_id %llu result %d\n", __func__, lreq,
2940 	     lreq->linger_id, req->r_result);
2941 	linger_reg_commit_complete(lreq, req->r_result);
2942 	lreq->committed = true;
2943 
2944 	if (!lreq->is_watch) {
2945 		struct ceph_osd_data *osd_data =
2946 		    osd_req_op_data(req, 0, notify, response_data);
2947 		void *p = page_address(osd_data->pages[0]);
2948 
2949 		WARN_ON(req->r_ops[0].op != CEPH_OSD_OP_NOTIFY ||
2950 			osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
2951 
2952 		/* make note of the notify_id */
2953 		if (req->r_ops[0].outdata_len >= sizeof(u64)) {
2954 			lreq->notify_id = ceph_decode_64(&p);
2955 			dout("lreq %p notify_id %llu\n", lreq,
2956 			     lreq->notify_id);
2957 		} else {
2958 			dout("lreq %p no notify_id\n", lreq);
2959 		}
2960 	}
2961 
2962 	mutex_unlock(&lreq->lock);
2963 	linger_put(lreq);
2964 }
2965 
2966 static int normalize_watch_error(int err)
2967 {
2968 	/*
2969 	 * Translate ENOENT -> ENOTCONN so that a delete->disconnection
2970 	 * notification and a failure to reconnect because we raced with
2971 	 * the delete appear the same to the user.
2972 	 */
2973 	if (err == -ENOENT)
2974 		err = -ENOTCONN;
2975 
2976 	return err;
2977 }
2978 
2979 static void linger_reconnect_cb(struct ceph_osd_request *req)
2980 {
2981 	struct ceph_osd_linger_request *lreq = req->r_priv;
2982 
2983 	mutex_lock(&lreq->lock);
2984 	dout("%s lreq %p linger_id %llu result %d last_error %d\n", __func__,
2985 	     lreq, lreq->linger_id, req->r_result, lreq->last_error);
2986 	if (req->r_result < 0) {
2987 		if (!lreq->last_error) {
2988 			lreq->last_error = normalize_watch_error(req->r_result);
2989 			queue_watch_error(lreq);
2990 		}
2991 	}
2992 
2993 	mutex_unlock(&lreq->lock);
2994 	linger_put(lreq);
2995 }
2996 
2997 static void send_linger(struct ceph_osd_linger_request *lreq)
2998 {
2999 	struct ceph_osd_request *req = lreq->reg_req;
3000 	struct ceph_osd_req_op *op = &req->r_ops[0];
3001 
3002 	verify_osdc_wrlocked(req->r_osdc);
3003 	dout("%s lreq %p linger_id %llu\n", __func__, lreq, lreq->linger_id);
3004 
3005 	if (req->r_osd)
3006 		cancel_linger_request(req);
3007 
3008 	request_reinit(req);
3009 	ceph_oid_copy(&req->r_base_oid, &lreq->t.base_oid);
3010 	ceph_oloc_copy(&req->r_base_oloc, &lreq->t.base_oloc);
3011 	req->r_flags = lreq->t.flags;
3012 	req->r_mtime = lreq->mtime;
3013 
3014 	mutex_lock(&lreq->lock);
3015 	if (lreq->is_watch && lreq->committed) {
3016 		WARN_ON(op->op != CEPH_OSD_OP_WATCH ||
3017 			op->watch.cookie != lreq->linger_id);
3018 		op->watch.op = CEPH_OSD_WATCH_OP_RECONNECT;
3019 		op->watch.gen = ++lreq->register_gen;
3020 		dout("lreq %p reconnect register_gen %u\n", lreq,
3021 		     op->watch.gen);
3022 		req->r_callback = linger_reconnect_cb;
3023 	} else {
3024 		if (!lreq->is_watch)
3025 			lreq->notify_id = 0;
3026 		else
3027 			WARN_ON(op->watch.op != CEPH_OSD_WATCH_OP_WATCH);
3028 		dout("lreq %p register\n", lreq);
3029 		req->r_callback = linger_commit_cb;
3030 	}
3031 	mutex_unlock(&lreq->lock);
3032 
3033 	req->r_priv = linger_get(lreq);
3034 	req->r_linger = true;
3035 
3036 	submit_request(req, true);
3037 }
3038 
3039 static void linger_ping_cb(struct ceph_osd_request *req)
3040 {
3041 	struct ceph_osd_linger_request *lreq = req->r_priv;
3042 
3043 	mutex_lock(&lreq->lock);
3044 	dout("%s lreq %p linger_id %llu result %d ping_sent %lu last_error %d\n",
3045 	     __func__, lreq, lreq->linger_id, req->r_result, lreq->ping_sent,
3046 	     lreq->last_error);
3047 	if (lreq->register_gen == req->r_ops[0].watch.gen) {
3048 		if (!req->r_result) {
3049 			lreq->watch_valid_thru = lreq->ping_sent;
3050 		} else if (!lreq->last_error) {
3051 			lreq->last_error = normalize_watch_error(req->r_result);
3052 			queue_watch_error(lreq);
3053 		}
3054 	} else {
3055 		dout("lreq %p register_gen %u ignoring old pong %u\n", lreq,
3056 		     lreq->register_gen, req->r_ops[0].watch.gen);
3057 	}
3058 
3059 	mutex_unlock(&lreq->lock);
3060 	linger_put(lreq);
3061 }
3062 
3063 static void send_linger_ping(struct ceph_osd_linger_request *lreq)
3064 {
3065 	struct ceph_osd_client *osdc = lreq->osdc;
3066 	struct ceph_osd_request *req = lreq->ping_req;
3067 	struct ceph_osd_req_op *op = &req->r_ops[0];
3068 
3069 	if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD)) {
3070 		dout("%s PAUSERD\n", __func__);
3071 		return;
3072 	}
3073 
3074 	lreq->ping_sent = jiffies;
3075 	dout("%s lreq %p linger_id %llu ping_sent %lu register_gen %u\n",
3076 	     __func__, lreq, lreq->linger_id, lreq->ping_sent,
3077 	     lreq->register_gen);
3078 
3079 	if (req->r_osd)
3080 		cancel_linger_request(req);
3081 
3082 	request_reinit(req);
3083 	target_copy(&req->r_t, &lreq->t);
3084 
3085 	WARN_ON(op->op != CEPH_OSD_OP_WATCH ||
3086 		op->watch.cookie != lreq->linger_id ||
3087 		op->watch.op != CEPH_OSD_WATCH_OP_PING);
3088 	op->watch.gen = lreq->register_gen;
3089 	req->r_callback = linger_ping_cb;
3090 	req->r_priv = linger_get(lreq);
3091 	req->r_linger = true;
3092 
3093 	ceph_osdc_get_request(req);
3094 	account_request(req);
3095 	req->r_tid = atomic64_inc_return(&osdc->last_tid);
3096 	link_request(lreq->osd, req);
3097 	send_request(req);
3098 }
3099 
3100 static void linger_submit(struct ceph_osd_linger_request *lreq)
3101 {
3102 	struct ceph_osd_client *osdc = lreq->osdc;
3103 	struct ceph_osd *osd;
3104 
3105 	down_write(&osdc->lock);
3106 	linger_register(lreq);
3107 	if (lreq->is_watch) {
3108 		lreq->reg_req->r_ops[0].watch.cookie = lreq->linger_id;
3109 		lreq->ping_req->r_ops[0].watch.cookie = lreq->linger_id;
3110 	} else {
3111 		lreq->reg_req->r_ops[0].notify.cookie = lreq->linger_id;
3112 	}
3113 
3114 	calc_target(osdc, &lreq->t, false);
3115 	osd = lookup_create_osd(osdc, lreq->t.osd, true);
3116 	link_linger(osd, lreq);
3117 
3118 	send_linger(lreq);
3119 	up_write(&osdc->lock);
3120 }
3121 
3122 static void cancel_linger_map_check(struct ceph_osd_linger_request *lreq)
3123 {
3124 	struct ceph_osd_client *osdc = lreq->osdc;
3125 	struct ceph_osd_linger_request *lookup_lreq;
3126 
3127 	verify_osdc_wrlocked(osdc);
3128 
3129 	lookup_lreq = lookup_linger_mc(&osdc->linger_map_checks,
3130 				       lreq->linger_id);
3131 	if (!lookup_lreq)
3132 		return;
3133 
3134 	WARN_ON(lookup_lreq != lreq);
3135 	erase_linger_mc(&osdc->linger_map_checks, lreq);
3136 	linger_put(lreq);
3137 }
3138 
3139 /*
3140  * @lreq has to be both registered and linked.
3141  */
3142 static void __linger_cancel(struct ceph_osd_linger_request *lreq)
3143 {
3144 	if (lreq->is_watch && lreq->ping_req->r_osd)
3145 		cancel_linger_request(lreq->ping_req);
3146 	if (lreq->reg_req->r_osd)
3147 		cancel_linger_request(lreq->reg_req);
3148 	cancel_linger_map_check(lreq);
3149 	unlink_linger(lreq->osd, lreq);
3150 	linger_unregister(lreq);
3151 }
3152 
3153 static void linger_cancel(struct ceph_osd_linger_request *lreq)
3154 {
3155 	struct ceph_osd_client *osdc = lreq->osdc;
3156 
3157 	down_write(&osdc->lock);
3158 	if (__linger_registered(lreq))
3159 		__linger_cancel(lreq);
3160 	up_write(&osdc->lock);
3161 }
3162 
3163 static void send_linger_map_check(struct ceph_osd_linger_request *lreq);
3164 
3165 static void check_linger_pool_dne(struct ceph_osd_linger_request *lreq)
3166 {
3167 	struct ceph_osd_client *osdc = lreq->osdc;
3168 	struct ceph_osdmap *map = osdc->osdmap;
3169 
3170 	verify_osdc_wrlocked(osdc);
3171 	WARN_ON(!map->epoch);
3172 
3173 	if (lreq->register_gen) {
3174 		lreq->map_dne_bound = map->epoch;
3175 		dout("%s lreq %p linger_id %llu pool disappeared\n", __func__,
3176 		     lreq, lreq->linger_id);
3177 	} else {
3178 		dout("%s lreq %p linger_id %llu map_dne_bound %u have %u\n",
3179 		     __func__, lreq, lreq->linger_id, lreq->map_dne_bound,
3180 		     map->epoch);
3181 	}
3182 
3183 	if (lreq->map_dne_bound) {
3184 		if (map->epoch >= lreq->map_dne_bound) {
3185 			/* we had a new enough map */
3186 			pr_info("linger_id %llu pool does not exist\n",
3187 				lreq->linger_id);
3188 			linger_reg_commit_complete(lreq, -ENOENT);
3189 			__linger_cancel(lreq);
3190 		}
3191 	} else {
3192 		send_linger_map_check(lreq);
3193 	}
3194 }
3195 
3196 static void linger_map_check_cb(struct ceph_mon_generic_request *greq)
3197 {
3198 	struct ceph_osd_client *osdc = &greq->monc->client->osdc;
3199 	struct ceph_osd_linger_request *lreq;
3200 	u64 linger_id = greq->private_data;
3201 
3202 	WARN_ON(greq->result || !greq->u.newest);
3203 
3204 	down_write(&osdc->lock);
3205 	lreq = lookup_linger_mc(&osdc->linger_map_checks, linger_id);
3206 	if (!lreq) {
3207 		dout("%s linger_id %llu dne\n", __func__, linger_id);
3208 		goto out_unlock;
3209 	}
3210 
3211 	dout("%s lreq %p linger_id %llu map_dne_bound %u newest %llu\n",
3212 	     __func__, lreq, lreq->linger_id, lreq->map_dne_bound,
3213 	     greq->u.newest);
3214 	if (!lreq->map_dne_bound)
3215 		lreq->map_dne_bound = greq->u.newest;
3216 	erase_linger_mc(&osdc->linger_map_checks, lreq);
3217 	check_linger_pool_dne(lreq);
3218 
3219 	linger_put(lreq);
3220 out_unlock:
3221 	up_write(&osdc->lock);
3222 }
3223 
3224 static void send_linger_map_check(struct ceph_osd_linger_request *lreq)
3225 {
3226 	struct ceph_osd_client *osdc = lreq->osdc;
3227 	struct ceph_osd_linger_request *lookup_lreq;
3228 	int ret;
3229 
3230 	verify_osdc_wrlocked(osdc);
3231 
3232 	lookup_lreq = lookup_linger_mc(&osdc->linger_map_checks,
3233 				       lreq->linger_id);
3234 	if (lookup_lreq) {
3235 		WARN_ON(lookup_lreq != lreq);
3236 		return;
3237 	}
3238 
3239 	linger_get(lreq);
3240 	insert_linger_mc(&osdc->linger_map_checks, lreq);
3241 	ret = ceph_monc_get_version_async(&osdc->client->monc, "osdmap",
3242 					  linger_map_check_cb, lreq->linger_id);
3243 	WARN_ON(ret);
3244 }
3245 
3246 static int linger_reg_commit_wait(struct ceph_osd_linger_request *lreq)
3247 {
3248 	int ret;
3249 
3250 	dout("%s lreq %p linger_id %llu\n", __func__, lreq, lreq->linger_id);
3251 	ret = wait_for_completion_interruptible(&lreq->reg_commit_wait);
3252 	return ret ?: lreq->reg_commit_error;
3253 }
3254 
3255 static int linger_notify_finish_wait(struct ceph_osd_linger_request *lreq)
3256 {
3257 	int ret;
3258 
3259 	dout("%s lreq %p linger_id %llu\n", __func__, lreq, lreq->linger_id);
3260 	ret = wait_for_completion_interruptible(&lreq->notify_finish_wait);
3261 	return ret ?: lreq->notify_finish_error;
3262 }
3263 
3264 /*
3265  * Timeout callback, called every N seconds.  When 1 or more OSD
3266  * requests has been active for more than N seconds, we send a keepalive
3267  * (tag + timestamp) to its OSD to ensure any communications channel
3268  * reset is detected.
3269  */
3270 static void handle_timeout(struct work_struct *work)
3271 {
3272 	struct ceph_osd_client *osdc =
3273 		container_of(work, struct ceph_osd_client, timeout_work.work);
3274 	struct ceph_options *opts = osdc->client->options;
3275 	unsigned long cutoff = jiffies - opts->osd_keepalive_timeout;
3276 	unsigned long expiry_cutoff = jiffies - opts->osd_request_timeout;
3277 	LIST_HEAD(slow_osds);
3278 	struct rb_node *n, *p;
3279 
3280 	dout("%s osdc %p\n", __func__, osdc);
3281 	down_write(&osdc->lock);
3282 
3283 	/*
3284 	 * ping osds that are a bit slow.  this ensures that if there
3285 	 * is a break in the TCP connection we will notice, and reopen
3286 	 * a connection with that osd (from the fault callback).
3287 	 */
3288 	for (n = rb_first(&osdc->osds); n; n = rb_next(n)) {
3289 		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
3290 		bool found = false;
3291 
3292 		for (p = rb_first(&osd->o_requests); p; ) {
3293 			struct ceph_osd_request *req =
3294 			    rb_entry(p, struct ceph_osd_request, r_node);
3295 
3296 			p = rb_next(p); /* abort_request() */
3297 
3298 			if (time_before(req->r_stamp, cutoff)) {
3299 				dout(" req %p tid %llu on osd%d is laggy\n",
3300 				     req, req->r_tid, osd->o_osd);
3301 				found = true;
3302 			}
3303 			if (opts->osd_request_timeout &&
3304 			    time_before(req->r_start_stamp, expiry_cutoff)) {
3305 				pr_err_ratelimited("tid %llu on osd%d timeout\n",
3306 				       req->r_tid, osd->o_osd);
3307 				abort_request(req, -ETIMEDOUT);
3308 			}
3309 		}
3310 		for (p = rb_first(&osd->o_linger_requests); p; p = rb_next(p)) {
3311 			struct ceph_osd_linger_request *lreq =
3312 			    rb_entry(p, struct ceph_osd_linger_request, node);
3313 
3314 			dout(" lreq %p linger_id %llu is served by osd%d\n",
3315 			     lreq, lreq->linger_id, osd->o_osd);
3316 			found = true;
3317 
3318 			mutex_lock(&lreq->lock);
3319 			if (lreq->is_watch && lreq->committed && !lreq->last_error)
3320 				send_linger_ping(lreq);
3321 			mutex_unlock(&lreq->lock);
3322 		}
3323 
3324 		if (found)
3325 			list_move_tail(&osd->o_keepalive_item, &slow_osds);
3326 	}
3327 
3328 	if (opts->osd_request_timeout) {
3329 		for (p = rb_first(&osdc->homeless_osd.o_requests); p; ) {
3330 			struct ceph_osd_request *req =
3331 			    rb_entry(p, struct ceph_osd_request, r_node);
3332 
3333 			p = rb_next(p); /* abort_request() */
3334 
3335 			if (time_before(req->r_start_stamp, expiry_cutoff)) {
3336 				pr_err_ratelimited("tid %llu on osd%d timeout\n",
3337 				       req->r_tid, osdc->homeless_osd.o_osd);
3338 				abort_request(req, -ETIMEDOUT);
3339 			}
3340 		}
3341 	}
3342 
3343 	if (atomic_read(&osdc->num_homeless) || !list_empty(&slow_osds))
3344 		maybe_request_map(osdc);
3345 
3346 	while (!list_empty(&slow_osds)) {
3347 		struct ceph_osd *osd = list_first_entry(&slow_osds,
3348 							struct ceph_osd,
3349 							o_keepalive_item);
3350 		list_del_init(&osd->o_keepalive_item);
3351 		ceph_con_keepalive(&osd->o_con);
3352 	}
3353 
3354 	up_write(&osdc->lock);
3355 	schedule_delayed_work(&osdc->timeout_work,
3356 			      osdc->client->options->osd_keepalive_timeout);
3357 }
3358 
3359 static void handle_osds_timeout(struct work_struct *work)
3360 {
3361 	struct ceph_osd_client *osdc =
3362 		container_of(work, struct ceph_osd_client,
3363 			     osds_timeout_work.work);
3364 	unsigned long delay = osdc->client->options->osd_idle_ttl / 4;
3365 	struct ceph_osd *osd, *nosd;
3366 
3367 	dout("%s osdc %p\n", __func__, osdc);
3368 	down_write(&osdc->lock);
3369 	list_for_each_entry_safe(osd, nosd, &osdc->osd_lru, o_osd_lru) {
3370 		if (time_before(jiffies, osd->lru_ttl))
3371 			break;
3372 
3373 		WARN_ON(!RB_EMPTY_ROOT(&osd->o_requests));
3374 		WARN_ON(!RB_EMPTY_ROOT(&osd->o_linger_requests));
3375 		close_osd(osd);
3376 	}
3377 
3378 	up_write(&osdc->lock);
3379 	schedule_delayed_work(&osdc->osds_timeout_work,
3380 			      round_jiffies_relative(delay));
3381 }
3382 
3383 static int ceph_oloc_decode(void **p, void *end,
3384 			    struct ceph_object_locator *oloc)
3385 {
3386 	u8 struct_v, struct_cv;
3387 	u32 len;
3388 	void *struct_end;
3389 	int ret = 0;
3390 
3391 	ceph_decode_need(p, end, 1 + 1 + 4, e_inval);
3392 	struct_v = ceph_decode_8(p);
3393 	struct_cv = ceph_decode_8(p);
3394 	if (struct_v < 3) {
3395 		pr_warn("got v %d < 3 cv %d of ceph_object_locator\n",
3396 			struct_v, struct_cv);
3397 		goto e_inval;
3398 	}
3399 	if (struct_cv > 6) {
3400 		pr_warn("got v %d cv %d > 6 of ceph_object_locator\n",
3401 			struct_v, struct_cv);
3402 		goto e_inval;
3403 	}
3404 	len = ceph_decode_32(p);
3405 	ceph_decode_need(p, end, len, e_inval);
3406 	struct_end = *p + len;
3407 
3408 	oloc->pool = ceph_decode_64(p);
3409 	*p += 4; /* skip preferred */
3410 
3411 	len = ceph_decode_32(p);
3412 	if (len > 0) {
3413 		pr_warn("ceph_object_locator::key is set\n");
3414 		goto e_inval;
3415 	}
3416 
3417 	if (struct_v >= 5) {
3418 		bool changed = false;
3419 
3420 		len = ceph_decode_32(p);
3421 		if (len > 0) {
3422 			ceph_decode_need(p, end, len, e_inval);
3423 			if (!oloc->pool_ns ||
3424 			    ceph_compare_string(oloc->pool_ns, *p, len))
3425 				changed = true;
3426 			*p += len;
3427 		} else {
3428 			if (oloc->pool_ns)
3429 				changed = true;
3430 		}
3431 		if (changed) {
3432 			/* redirect changes namespace */
3433 			pr_warn("ceph_object_locator::nspace is changed\n");
3434 			goto e_inval;
3435 		}
3436 	}
3437 
3438 	if (struct_v >= 6) {
3439 		s64 hash = ceph_decode_64(p);
3440 		if (hash != -1) {
3441 			pr_warn("ceph_object_locator::hash is set\n");
3442 			goto e_inval;
3443 		}
3444 	}
3445 
3446 	/* skip the rest */
3447 	*p = struct_end;
3448 out:
3449 	return ret;
3450 
3451 e_inval:
3452 	ret = -EINVAL;
3453 	goto out;
3454 }
3455 
3456 static int ceph_redirect_decode(void **p, void *end,
3457 				struct ceph_request_redirect *redir)
3458 {
3459 	u8 struct_v, struct_cv;
3460 	u32 len;
3461 	void *struct_end;
3462 	int ret;
3463 
3464 	ceph_decode_need(p, end, 1 + 1 + 4, e_inval);
3465 	struct_v = ceph_decode_8(p);
3466 	struct_cv = ceph_decode_8(p);
3467 	if (struct_cv > 1) {
3468 		pr_warn("got v %d cv %d > 1 of ceph_request_redirect\n",
3469 			struct_v, struct_cv);
3470 		goto e_inval;
3471 	}
3472 	len = ceph_decode_32(p);
3473 	ceph_decode_need(p, end, len, e_inval);
3474 	struct_end = *p + len;
3475 
3476 	ret = ceph_oloc_decode(p, end, &redir->oloc);
3477 	if (ret)
3478 		goto out;
3479 
3480 	len = ceph_decode_32(p);
3481 	if (len > 0) {
3482 		pr_warn("ceph_request_redirect::object_name is set\n");
3483 		goto e_inval;
3484 	}
3485 
3486 	/* skip the rest */
3487 	*p = struct_end;
3488 out:
3489 	return ret;
3490 
3491 e_inval:
3492 	ret = -EINVAL;
3493 	goto out;
3494 }
3495 
3496 struct MOSDOpReply {
3497 	struct ceph_pg pgid;
3498 	u64 flags;
3499 	int result;
3500 	u32 epoch;
3501 	int num_ops;
3502 	u32 outdata_len[CEPH_OSD_MAX_OPS];
3503 	s32 rval[CEPH_OSD_MAX_OPS];
3504 	int retry_attempt;
3505 	struct ceph_eversion replay_version;
3506 	u64 user_version;
3507 	struct ceph_request_redirect redirect;
3508 };
3509 
3510 static int decode_MOSDOpReply(const struct ceph_msg *msg, struct MOSDOpReply *m)
3511 {
3512 	void *p = msg->front.iov_base;
3513 	void *const end = p + msg->front.iov_len;
3514 	u16 version = le16_to_cpu(msg->hdr.version);
3515 	struct ceph_eversion bad_replay_version;
3516 	u8 decode_redir;
3517 	u32 len;
3518 	int ret;
3519 	int i;
3520 
3521 	ceph_decode_32_safe(&p, end, len, e_inval);
3522 	ceph_decode_need(&p, end, len, e_inval);
3523 	p += len; /* skip oid */
3524 
3525 	ret = ceph_decode_pgid(&p, end, &m->pgid);
3526 	if (ret)
3527 		return ret;
3528 
3529 	ceph_decode_64_safe(&p, end, m->flags, e_inval);
3530 	ceph_decode_32_safe(&p, end, m->result, e_inval);
3531 	ceph_decode_need(&p, end, sizeof(bad_replay_version), e_inval);
3532 	memcpy(&bad_replay_version, p, sizeof(bad_replay_version));
3533 	p += sizeof(bad_replay_version);
3534 	ceph_decode_32_safe(&p, end, m->epoch, e_inval);
3535 
3536 	ceph_decode_32_safe(&p, end, m->num_ops, e_inval);
3537 	if (m->num_ops > ARRAY_SIZE(m->outdata_len))
3538 		goto e_inval;
3539 
3540 	ceph_decode_need(&p, end, m->num_ops * sizeof(struct ceph_osd_op),
3541 			 e_inval);
3542 	for (i = 0; i < m->num_ops; i++) {
3543 		struct ceph_osd_op *op = p;
3544 
3545 		m->outdata_len[i] = le32_to_cpu(op->payload_len);
3546 		p += sizeof(*op);
3547 	}
3548 
3549 	ceph_decode_32_safe(&p, end, m->retry_attempt, e_inval);
3550 	for (i = 0; i < m->num_ops; i++)
3551 		ceph_decode_32_safe(&p, end, m->rval[i], e_inval);
3552 
3553 	if (version >= 5) {
3554 		ceph_decode_need(&p, end, sizeof(m->replay_version), e_inval);
3555 		memcpy(&m->replay_version, p, sizeof(m->replay_version));
3556 		p += sizeof(m->replay_version);
3557 		ceph_decode_64_safe(&p, end, m->user_version, e_inval);
3558 	} else {
3559 		m->replay_version = bad_replay_version; /* struct */
3560 		m->user_version = le64_to_cpu(m->replay_version.version);
3561 	}
3562 
3563 	if (version >= 6) {
3564 		if (version >= 7)
3565 			ceph_decode_8_safe(&p, end, decode_redir, e_inval);
3566 		else
3567 			decode_redir = 1;
3568 	} else {
3569 		decode_redir = 0;
3570 	}
3571 
3572 	if (decode_redir) {
3573 		ret = ceph_redirect_decode(&p, end, &m->redirect);
3574 		if (ret)
3575 			return ret;
3576 	} else {
3577 		ceph_oloc_init(&m->redirect.oloc);
3578 	}
3579 
3580 	return 0;
3581 
3582 e_inval:
3583 	return -EINVAL;
3584 }
3585 
3586 /*
3587  * Handle MOSDOpReply.  Set ->r_result and call the callback if it is
3588  * specified.
3589  */
3590 static void handle_reply(struct ceph_osd *osd, struct ceph_msg *msg)
3591 {
3592 	struct ceph_osd_client *osdc = osd->o_osdc;
3593 	struct ceph_osd_request *req;
3594 	struct MOSDOpReply m;
3595 	u64 tid = le64_to_cpu(msg->hdr.tid);
3596 	u32 data_len = 0;
3597 	int ret;
3598 	int i;
3599 
3600 	dout("%s msg %p tid %llu\n", __func__, msg, tid);
3601 
3602 	down_read(&osdc->lock);
3603 	if (!osd_registered(osd)) {
3604 		dout("%s osd%d unknown\n", __func__, osd->o_osd);
3605 		goto out_unlock_osdc;
3606 	}
3607 	WARN_ON(osd->o_osd != le64_to_cpu(msg->hdr.src.num));
3608 
3609 	mutex_lock(&osd->lock);
3610 	req = lookup_request(&osd->o_requests, tid);
3611 	if (!req) {
3612 		dout("%s osd%d tid %llu unknown\n", __func__, osd->o_osd, tid);
3613 		goto out_unlock_session;
3614 	}
3615 
3616 	m.redirect.oloc.pool_ns = req->r_t.target_oloc.pool_ns;
3617 	ret = decode_MOSDOpReply(msg, &m);
3618 	m.redirect.oloc.pool_ns = NULL;
3619 	if (ret) {
3620 		pr_err("failed to decode MOSDOpReply for tid %llu: %d\n",
3621 		       req->r_tid, ret);
3622 		ceph_msg_dump(msg);
3623 		goto fail_request;
3624 	}
3625 	dout("%s req %p tid %llu flags 0x%llx pgid %llu.%x epoch %u attempt %d v %u'%llu uv %llu\n",
3626 	     __func__, req, req->r_tid, m.flags, m.pgid.pool, m.pgid.seed,
3627 	     m.epoch, m.retry_attempt, le32_to_cpu(m.replay_version.epoch),
3628 	     le64_to_cpu(m.replay_version.version), m.user_version);
3629 
3630 	if (m.retry_attempt >= 0) {
3631 		if (m.retry_attempt != req->r_attempts - 1) {
3632 			dout("req %p tid %llu retry_attempt %d != %d, ignoring\n",
3633 			     req, req->r_tid, m.retry_attempt,
3634 			     req->r_attempts - 1);
3635 			goto out_unlock_session;
3636 		}
3637 	} else {
3638 		WARN_ON(1); /* MOSDOpReply v4 is assumed */
3639 	}
3640 
3641 	if (!ceph_oloc_empty(&m.redirect.oloc)) {
3642 		dout("req %p tid %llu redirect pool %lld\n", req, req->r_tid,
3643 		     m.redirect.oloc.pool);
3644 		unlink_request(osd, req);
3645 		mutex_unlock(&osd->lock);
3646 
3647 		/*
3648 		 * Not ceph_oloc_copy() - changing pool_ns is not
3649 		 * supported.
3650 		 */
3651 		req->r_t.target_oloc.pool = m.redirect.oloc.pool;
3652 		req->r_flags |= CEPH_OSD_FLAG_REDIRECTED;
3653 		req->r_tid = 0;
3654 		__submit_request(req, false);
3655 		goto out_unlock_osdc;
3656 	}
3657 
3658 	if (m.num_ops != req->r_num_ops) {
3659 		pr_err("num_ops %d != %d for tid %llu\n", m.num_ops,
3660 		       req->r_num_ops, req->r_tid);
3661 		goto fail_request;
3662 	}
3663 	for (i = 0; i < req->r_num_ops; i++) {
3664 		dout(" req %p tid %llu op %d rval %d len %u\n", req,
3665 		     req->r_tid, i, m.rval[i], m.outdata_len[i]);
3666 		req->r_ops[i].rval = m.rval[i];
3667 		req->r_ops[i].outdata_len = m.outdata_len[i];
3668 		data_len += m.outdata_len[i];
3669 	}
3670 	if (data_len != le32_to_cpu(msg->hdr.data_len)) {
3671 		pr_err("sum of lens %u != %u for tid %llu\n", data_len,
3672 		       le32_to_cpu(msg->hdr.data_len), req->r_tid);
3673 		goto fail_request;
3674 	}
3675 	dout("%s req %p tid %llu result %d data_len %u\n", __func__,
3676 	     req, req->r_tid, m.result, data_len);
3677 
3678 	/*
3679 	 * Since we only ever request ONDISK, we should only ever get
3680 	 * one (type of) reply back.
3681 	 */
3682 	WARN_ON(!(m.flags & CEPH_OSD_FLAG_ONDISK));
3683 	req->r_result = m.result ?: data_len;
3684 	finish_request(req);
3685 	mutex_unlock(&osd->lock);
3686 	up_read(&osdc->lock);
3687 
3688 	__complete_request(req);
3689 	return;
3690 
3691 fail_request:
3692 	complete_request(req, -EIO);
3693 out_unlock_session:
3694 	mutex_unlock(&osd->lock);
3695 out_unlock_osdc:
3696 	up_read(&osdc->lock);
3697 }
3698 
3699 static void set_pool_was_full(struct ceph_osd_client *osdc)
3700 {
3701 	struct rb_node *n;
3702 
3703 	for (n = rb_first(&osdc->osdmap->pg_pools); n; n = rb_next(n)) {
3704 		struct ceph_pg_pool_info *pi =
3705 		    rb_entry(n, struct ceph_pg_pool_info, node);
3706 
3707 		pi->was_full = __pool_full(pi);
3708 	}
3709 }
3710 
3711 static bool pool_cleared_full(struct ceph_osd_client *osdc, s64 pool_id)
3712 {
3713 	struct ceph_pg_pool_info *pi;
3714 
3715 	pi = ceph_pg_pool_by_id(osdc->osdmap, pool_id);
3716 	if (!pi)
3717 		return false;
3718 
3719 	return pi->was_full && !__pool_full(pi);
3720 }
3721 
3722 static enum calc_target_result
3723 recalc_linger_target(struct ceph_osd_linger_request *lreq)
3724 {
3725 	struct ceph_osd_client *osdc = lreq->osdc;
3726 	enum calc_target_result ct_res;
3727 
3728 	ct_res = calc_target(osdc, &lreq->t, true);
3729 	if (ct_res == CALC_TARGET_NEED_RESEND) {
3730 		struct ceph_osd *osd;
3731 
3732 		osd = lookup_create_osd(osdc, lreq->t.osd, true);
3733 		if (osd != lreq->osd) {
3734 			unlink_linger(lreq->osd, lreq);
3735 			link_linger(osd, lreq);
3736 		}
3737 	}
3738 
3739 	return ct_res;
3740 }
3741 
3742 /*
3743  * Requeue requests whose mapping to an OSD has changed.
3744  */
3745 static void scan_requests(struct ceph_osd *osd,
3746 			  bool force_resend,
3747 			  bool cleared_full,
3748 			  bool check_pool_cleared_full,
3749 			  struct rb_root *need_resend,
3750 			  struct list_head *need_resend_linger)
3751 {
3752 	struct ceph_osd_client *osdc = osd->o_osdc;
3753 	struct rb_node *n;
3754 	bool force_resend_writes;
3755 
3756 	for (n = rb_first(&osd->o_linger_requests); n; ) {
3757 		struct ceph_osd_linger_request *lreq =
3758 		    rb_entry(n, struct ceph_osd_linger_request, node);
3759 		enum calc_target_result ct_res;
3760 
3761 		n = rb_next(n); /* recalc_linger_target() */
3762 
3763 		dout("%s lreq %p linger_id %llu\n", __func__, lreq,
3764 		     lreq->linger_id);
3765 		ct_res = recalc_linger_target(lreq);
3766 		switch (ct_res) {
3767 		case CALC_TARGET_NO_ACTION:
3768 			force_resend_writes = cleared_full ||
3769 			    (check_pool_cleared_full &&
3770 			     pool_cleared_full(osdc, lreq->t.base_oloc.pool));
3771 			if (!force_resend && !force_resend_writes)
3772 				break;
3773 
3774 			/* fall through */
3775 		case CALC_TARGET_NEED_RESEND:
3776 			cancel_linger_map_check(lreq);
3777 			/*
3778 			 * scan_requests() for the previous epoch(s)
3779 			 * may have already added it to the list, since
3780 			 * it's not unlinked here.
3781 			 */
3782 			if (list_empty(&lreq->scan_item))
3783 				list_add_tail(&lreq->scan_item, need_resend_linger);
3784 			break;
3785 		case CALC_TARGET_POOL_DNE:
3786 			list_del_init(&lreq->scan_item);
3787 			check_linger_pool_dne(lreq);
3788 			break;
3789 		}
3790 	}
3791 
3792 	for (n = rb_first(&osd->o_requests); n; ) {
3793 		struct ceph_osd_request *req =
3794 		    rb_entry(n, struct ceph_osd_request, r_node);
3795 		enum calc_target_result ct_res;
3796 
3797 		n = rb_next(n); /* unlink_request(), check_pool_dne() */
3798 
3799 		dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
3800 		ct_res = calc_target(osdc, &req->r_t, false);
3801 		switch (ct_res) {
3802 		case CALC_TARGET_NO_ACTION:
3803 			force_resend_writes = cleared_full ||
3804 			    (check_pool_cleared_full &&
3805 			     pool_cleared_full(osdc, req->r_t.base_oloc.pool));
3806 			if (!force_resend &&
3807 			    (!(req->r_flags & CEPH_OSD_FLAG_WRITE) ||
3808 			     !force_resend_writes))
3809 				break;
3810 
3811 			/* fall through */
3812 		case CALC_TARGET_NEED_RESEND:
3813 			cancel_map_check(req);
3814 			unlink_request(osd, req);
3815 			insert_request(need_resend, req);
3816 			break;
3817 		case CALC_TARGET_POOL_DNE:
3818 			check_pool_dne(req);
3819 			break;
3820 		}
3821 	}
3822 }
3823 
3824 static int handle_one_map(struct ceph_osd_client *osdc,
3825 			  void *p, void *end, bool incremental,
3826 			  struct rb_root *need_resend,
3827 			  struct list_head *need_resend_linger)
3828 {
3829 	struct ceph_osdmap *newmap;
3830 	struct rb_node *n;
3831 	bool skipped_map = false;
3832 	bool was_full;
3833 
3834 	was_full = ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL);
3835 	set_pool_was_full(osdc);
3836 
3837 	if (incremental)
3838 		newmap = osdmap_apply_incremental(&p, end, osdc->osdmap);
3839 	else
3840 		newmap = ceph_osdmap_decode(&p, end);
3841 	if (IS_ERR(newmap))
3842 		return PTR_ERR(newmap);
3843 
3844 	if (newmap != osdc->osdmap) {
3845 		/*
3846 		 * Preserve ->was_full before destroying the old map.
3847 		 * For pools that weren't in the old map, ->was_full
3848 		 * should be false.
3849 		 */
3850 		for (n = rb_first(&newmap->pg_pools); n; n = rb_next(n)) {
3851 			struct ceph_pg_pool_info *pi =
3852 			    rb_entry(n, struct ceph_pg_pool_info, node);
3853 			struct ceph_pg_pool_info *old_pi;
3854 
3855 			old_pi = ceph_pg_pool_by_id(osdc->osdmap, pi->id);
3856 			if (old_pi)
3857 				pi->was_full = old_pi->was_full;
3858 			else
3859 				WARN_ON(pi->was_full);
3860 		}
3861 
3862 		if (osdc->osdmap->epoch &&
3863 		    osdc->osdmap->epoch + 1 < newmap->epoch) {
3864 			WARN_ON(incremental);
3865 			skipped_map = true;
3866 		}
3867 
3868 		ceph_osdmap_destroy(osdc->osdmap);
3869 		osdc->osdmap = newmap;
3870 	}
3871 
3872 	was_full &= !ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL);
3873 	scan_requests(&osdc->homeless_osd, skipped_map, was_full, true,
3874 		      need_resend, need_resend_linger);
3875 
3876 	for (n = rb_first(&osdc->osds); n; ) {
3877 		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
3878 
3879 		n = rb_next(n); /* close_osd() */
3880 
3881 		scan_requests(osd, skipped_map, was_full, true, need_resend,
3882 			      need_resend_linger);
3883 		if (!ceph_osd_is_up(osdc->osdmap, osd->o_osd) ||
3884 		    memcmp(&osd->o_con.peer_addr,
3885 			   ceph_osd_addr(osdc->osdmap, osd->o_osd),
3886 			   sizeof(struct ceph_entity_addr)))
3887 			close_osd(osd);
3888 	}
3889 
3890 	return 0;
3891 }
3892 
3893 static void kick_requests(struct ceph_osd_client *osdc,
3894 			  struct rb_root *need_resend,
3895 			  struct list_head *need_resend_linger)
3896 {
3897 	struct ceph_osd_linger_request *lreq, *nlreq;
3898 	enum calc_target_result ct_res;
3899 	struct rb_node *n;
3900 
3901 	/* make sure need_resend targets reflect latest map */
3902 	for (n = rb_first(need_resend); n; ) {
3903 		struct ceph_osd_request *req =
3904 		    rb_entry(n, struct ceph_osd_request, r_node);
3905 
3906 		n = rb_next(n);
3907 
3908 		if (req->r_t.epoch < osdc->osdmap->epoch) {
3909 			ct_res = calc_target(osdc, &req->r_t, false);
3910 			if (ct_res == CALC_TARGET_POOL_DNE) {
3911 				erase_request(need_resend, req);
3912 				check_pool_dne(req);
3913 			}
3914 		}
3915 	}
3916 
3917 	for (n = rb_first(need_resend); n; ) {
3918 		struct ceph_osd_request *req =
3919 		    rb_entry(n, struct ceph_osd_request, r_node);
3920 		struct ceph_osd *osd;
3921 
3922 		n = rb_next(n);
3923 		erase_request(need_resend, req); /* before link_request() */
3924 
3925 		osd = lookup_create_osd(osdc, req->r_t.osd, true);
3926 		link_request(osd, req);
3927 		if (!req->r_linger) {
3928 			if (!osd_homeless(osd) && !req->r_t.paused)
3929 				send_request(req);
3930 		} else {
3931 			cancel_linger_request(req);
3932 		}
3933 	}
3934 
3935 	list_for_each_entry_safe(lreq, nlreq, need_resend_linger, scan_item) {
3936 		if (!osd_homeless(lreq->osd))
3937 			send_linger(lreq);
3938 
3939 		list_del_init(&lreq->scan_item);
3940 	}
3941 }
3942 
3943 /*
3944  * Process updated osd map.
3945  *
3946  * The message contains any number of incremental and full maps, normally
3947  * indicating some sort of topology change in the cluster.  Kick requests
3948  * off to different OSDs as needed.
3949  */
3950 void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
3951 {
3952 	void *p = msg->front.iov_base;
3953 	void *const end = p + msg->front.iov_len;
3954 	u32 nr_maps, maplen;
3955 	u32 epoch;
3956 	struct ceph_fsid fsid;
3957 	struct rb_root need_resend = RB_ROOT;
3958 	LIST_HEAD(need_resend_linger);
3959 	bool handled_incremental = false;
3960 	bool was_pauserd, was_pausewr;
3961 	bool pauserd, pausewr;
3962 	int err;
3963 
3964 	dout("%s have %u\n", __func__, osdc->osdmap->epoch);
3965 	down_write(&osdc->lock);
3966 
3967 	/* verify fsid */
3968 	ceph_decode_need(&p, end, sizeof(fsid), bad);
3969 	ceph_decode_copy(&p, &fsid, sizeof(fsid));
3970 	if (ceph_check_fsid(osdc->client, &fsid) < 0)
3971 		goto bad;
3972 
3973 	was_pauserd = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD);
3974 	was_pausewr = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR) ||
3975 		      ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
3976 		      have_pool_full(osdc);
3977 
3978 	/* incremental maps */
3979 	ceph_decode_32_safe(&p, end, nr_maps, bad);
3980 	dout(" %d inc maps\n", nr_maps);
3981 	while (nr_maps > 0) {
3982 		ceph_decode_need(&p, end, 2*sizeof(u32), bad);
3983 		epoch = ceph_decode_32(&p);
3984 		maplen = ceph_decode_32(&p);
3985 		ceph_decode_need(&p, end, maplen, bad);
3986 		if (osdc->osdmap->epoch &&
3987 		    osdc->osdmap->epoch + 1 == epoch) {
3988 			dout("applying incremental map %u len %d\n",
3989 			     epoch, maplen);
3990 			err = handle_one_map(osdc, p, p + maplen, true,
3991 					     &need_resend, &need_resend_linger);
3992 			if (err)
3993 				goto bad;
3994 			handled_incremental = true;
3995 		} else {
3996 			dout("ignoring incremental map %u len %d\n",
3997 			     epoch, maplen);
3998 		}
3999 		p += maplen;
4000 		nr_maps--;
4001 	}
4002 	if (handled_incremental)
4003 		goto done;
4004 
4005 	/* full maps */
4006 	ceph_decode_32_safe(&p, end, nr_maps, bad);
4007 	dout(" %d full maps\n", nr_maps);
4008 	while (nr_maps) {
4009 		ceph_decode_need(&p, end, 2*sizeof(u32), bad);
4010 		epoch = ceph_decode_32(&p);
4011 		maplen = ceph_decode_32(&p);
4012 		ceph_decode_need(&p, end, maplen, bad);
4013 		if (nr_maps > 1) {
4014 			dout("skipping non-latest full map %u len %d\n",
4015 			     epoch, maplen);
4016 		} else if (osdc->osdmap->epoch >= epoch) {
4017 			dout("skipping full map %u len %d, "
4018 			     "older than our %u\n", epoch, maplen,
4019 			     osdc->osdmap->epoch);
4020 		} else {
4021 			dout("taking full map %u len %d\n", epoch, maplen);
4022 			err = handle_one_map(osdc, p, p + maplen, false,
4023 					     &need_resend, &need_resend_linger);
4024 			if (err)
4025 				goto bad;
4026 		}
4027 		p += maplen;
4028 		nr_maps--;
4029 	}
4030 
4031 done:
4032 	/*
4033 	 * subscribe to subsequent osdmap updates if full to ensure
4034 	 * we find out when we are no longer full and stop returning
4035 	 * ENOSPC.
4036 	 */
4037 	pauserd = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD);
4038 	pausewr = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR) ||
4039 		  ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
4040 		  have_pool_full(osdc);
4041 	if (was_pauserd || was_pausewr || pauserd || pausewr ||
4042 	    osdc->osdmap->epoch < osdc->epoch_barrier)
4043 		maybe_request_map(osdc);
4044 
4045 	kick_requests(osdc, &need_resend, &need_resend_linger);
4046 
4047 	ceph_osdc_abort_on_full(osdc);
4048 	ceph_monc_got_map(&osdc->client->monc, CEPH_SUB_OSDMAP,
4049 			  osdc->osdmap->epoch);
4050 	up_write(&osdc->lock);
4051 	wake_up_all(&osdc->client->auth_wq);
4052 	return;
4053 
4054 bad:
4055 	pr_err("osdc handle_map corrupt msg\n");
4056 	ceph_msg_dump(msg);
4057 	up_write(&osdc->lock);
4058 }
4059 
4060 /*
4061  * Resubmit requests pending on the given osd.
4062  */
4063 static void kick_osd_requests(struct ceph_osd *osd)
4064 {
4065 	struct rb_node *n;
4066 
4067 	clear_backoffs(osd);
4068 
4069 	for (n = rb_first(&osd->o_requests); n; ) {
4070 		struct ceph_osd_request *req =
4071 		    rb_entry(n, struct ceph_osd_request, r_node);
4072 
4073 		n = rb_next(n); /* cancel_linger_request() */
4074 
4075 		if (!req->r_linger) {
4076 			if (!req->r_t.paused)
4077 				send_request(req);
4078 		} else {
4079 			cancel_linger_request(req);
4080 		}
4081 	}
4082 	for (n = rb_first(&osd->o_linger_requests); n; n = rb_next(n)) {
4083 		struct ceph_osd_linger_request *lreq =
4084 		    rb_entry(n, struct ceph_osd_linger_request, node);
4085 
4086 		send_linger(lreq);
4087 	}
4088 }
4089 
4090 /*
4091  * If the osd connection drops, we need to resubmit all requests.
4092  */
4093 static void osd_fault(struct ceph_connection *con)
4094 {
4095 	struct ceph_osd *osd = con->private;
4096 	struct ceph_osd_client *osdc = osd->o_osdc;
4097 
4098 	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
4099 
4100 	down_write(&osdc->lock);
4101 	if (!osd_registered(osd)) {
4102 		dout("%s osd%d unknown\n", __func__, osd->o_osd);
4103 		goto out_unlock;
4104 	}
4105 
4106 	if (!reopen_osd(osd))
4107 		kick_osd_requests(osd);
4108 	maybe_request_map(osdc);
4109 
4110 out_unlock:
4111 	up_write(&osdc->lock);
4112 }
4113 
4114 struct MOSDBackoff {
4115 	struct ceph_spg spgid;
4116 	u32 map_epoch;
4117 	u8 op;
4118 	u64 id;
4119 	struct ceph_hobject_id *begin;
4120 	struct ceph_hobject_id *end;
4121 };
4122 
4123 static int decode_MOSDBackoff(const struct ceph_msg *msg, struct MOSDBackoff *m)
4124 {
4125 	void *p = msg->front.iov_base;
4126 	void *const end = p + msg->front.iov_len;
4127 	u8 struct_v;
4128 	u32 struct_len;
4129 	int ret;
4130 
4131 	ret = ceph_start_decoding(&p, end, 1, "spg_t", &struct_v, &struct_len);
4132 	if (ret)
4133 		return ret;
4134 
4135 	ret = ceph_decode_pgid(&p, end, &m->spgid.pgid);
4136 	if (ret)
4137 		return ret;
4138 
4139 	ceph_decode_8_safe(&p, end, m->spgid.shard, e_inval);
4140 	ceph_decode_32_safe(&p, end, m->map_epoch, e_inval);
4141 	ceph_decode_8_safe(&p, end, m->op, e_inval);
4142 	ceph_decode_64_safe(&p, end, m->id, e_inval);
4143 
4144 	m->begin = kzalloc(sizeof(*m->begin), GFP_NOIO);
4145 	if (!m->begin)
4146 		return -ENOMEM;
4147 
4148 	ret = decode_hoid(&p, end, m->begin);
4149 	if (ret) {
4150 		free_hoid(m->begin);
4151 		return ret;
4152 	}
4153 
4154 	m->end = kzalloc(sizeof(*m->end), GFP_NOIO);
4155 	if (!m->end) {
4156 		free_hoid(m->begin);
4157 		return -ENOMEM;
4158 	}
4159 
4160 	ret = decode_hoid(&p, end, m->end);
4161 	if (ret) {
4162 		free_hoid(m->begin);
4163 		free_hoid(m->end);
4164 		return ret;
4165 	}
4166 
4167 	return 0;
4168 
4169 e_inval:
4170 	return -EINVAL;
4171 }
4172 
4173 static struct ceph_msg *create_backoff_message(
4174 				const struct ceph_osd_backoff *backoff,
4175 				u32 map_epoch)
4176 {
4177 	struct ceph_msg *msg;
4178 	void *p, *end;
4179 	int msg_size;
4180 
4181 	msg_size = CEPH_ENCODING_START_BLK_LEN +
4182 			CEPH_PGID_ENCODING_LEN + 1; /* spgid */
4183 	msg_size += 4 + 1 + 8; /* map_epoch, op, id */
4184 	msg_size += CEPH_ENCODING_START_BLK_LEN +
4185 			hoid_encoding_size(backoff->begin);
4186 	msg_size += CEPH_ENCODING_START_BLK_LEN +
4187 			hoid_encoding_size(backoff->end);
4188 
4189 	msg = ceph_msg_new(CEPH_MSG_OSD_BACKOFF, msg_size, GFP_NOIO, true);
4190 	if (!msg)
4191 		return NULL;
4192 
4193 	p = msg->front.iov_base;
4194 	end = p + msg->front_alloc_len;
4195 
4196 	encode_spgid(&p, &backoff->spgid);
4197 	ceph_encode_32(&p, map_epoch);
4198 	ceph_encode_8(&p, CEPH_OSD_BACKOFF_OP_ACK_BLOCK);
4199 	ceph_encode_64(&p, backoff->id);
4200 	encode_hoid(&p, end, backoff->begin);
4201 	encode_hoid(&p, end, backoff->end);
4202 	BUG_ON(p != end);
4203 
4204 	msg->front.iov_len = p - msg->front.iov_base;
4205 	msg->hdr.version = cpu_to_le16(1); /* MOSDBackoff v1 */
4206 	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
4207 
4208 	return msg;
4209 }
4210 
4211 static void handle_backoff_block(struct ceph_osd *osd, struct MOSDBackoff *m)
4212 {
4213 	struct ceph_spg_mapping *spg;
4214 	struct ceph_osd_backoff *backoff;
4215 	struct ceph_msg *msg;
4216 
4217 	dout("%s osd%d spgid %llu.%xs%d id %llu\n", __func__, osd->o_osd,
4218 	     m->spgid.pgid.pool, m->spgid.pgid.seed, m->spgid.shard, m->id);
4219 
4220 	spg = lookup_spg_mapping(&osd->o_backoff_mappings, &m->spgid);
4221 	if (!spg) {
4222 		spg = alloc_spg_mapping();
4223 		if (!spg) {
4224 			pr_err("%s failed to allocate spg\n", __func__);
4225 			return;
4226 		}
4227 		spg->spgid = m->spgid; /* struct */
4228 		insert_spg_mapping(&osd->o_backoff_mappings, spg);
4229 	}
4230 
4231 	backoff = alloc_backoff();
4232 	if (!backoff) {
4233 		pr_err("%s failed to allocate backoff\n", __func__);
4234 		return;
4235 	}
4236 	backoff->spgid = m->spgid; /* struct */
4237 	backoff->id = m->id;
4238 	backoff->begin = m->begin;
4239 	m->begin = NULL; /* backoff now owns this */
4240 	backoff->end = m->end;
4241 	m->end = NULL;   /* ditto */
4242 
4243 	insert_backoff(&spg->backoffs, backoff);
4244 	insert_backoff_by_id(&osd->o_backoffs_by_id, backoff);
4245 
4246 	/*
4247 	 * Ack with original backoff's epoch so that the OSD can
4248 	 * discard this if there was a PG split.
4249 	 */
4250 	msg = create_backoff_message(backoff, m->map_epoch);
4251 	if (!msg) {
4252 		pr_err("%s failed to allocate msg\n", __func__);
4253 		return;
4254 	}
4255 	ceph_con_send(&osd->o_con, msg);
4256 }
4257 
4258 static bool target_contained_by(const struct ceph_osd_request_target *t,
4259 				const struct ceph_hobject_id *begin,
4260 				const struct ceph_hobject_id *end)
4261 {
4262 	struct ceph_hobject_id hoid;
4263 	int cmp;
4264 
4265 	hoid_fill_from_target(&hoid, t);
4266 	cmp = hoid_compare(&hoid, begin);
4267 	return !cmp || (cmp > 0 && hoid_compare(&hoid, end) < 0);
4268 }
4269 
4270 static void handle_backoff_unblock(struct ceph_osd *osd,
4271 				   const struct MOSDBackoff *m)
4272 {
4273 	struct ceph_spg_mapping *spg;
4274 	struct ceph_osd_backoff *backoff;
4275 	struct rb_node *n;
4276 
4277 	dout("%s osd%d spgid %llu.%xs%d id %llu\n", __func__, osd->o_osd,
4278 	     m->spgid.pgid.pool, m->spgid.pgid.seed, m->spgid.shard, m->id);
4279 
4280 	backoff = lookup_backoff_by_id(&osd->o_backoffs_by_id, m->id);
4281 	if (!backoff) {
4282 		pr_err("%s osd%d spgid %llu.%xs%d id %llu backoff dne\n",
4283 		       __func__, osd->o_osd, m->spgid.pgid.pool,
4284 		       m->spgid.pgid.seed, m->spgid.shard, m->id);
4285 		return;
4286 	}
4287 
4288 	if (hoid_compare(backoff->begin, m->begin) &&
4289 	    hoid_compare(backoff->end, m->end)) {
4290 		pr_err("%s osd%d spgid %llu.%xs%d id %llu bad range?\n",
4291 		       __func__, osd->o_osd, m->spgid.pgid.pool,
4292 		       m->spgid.pgid.seed, m->spgid.shard, m->id);
4293 		/* unblock it anyway... */
4294 	}
4295 
4296 	spg = lookup_spg_mapping(&osd->o_backoff_mappings, &backoff->spgid);
4297 	BUG_ON(!spg);
4298 
4299 	erase_backoff(&spg->backoffs, backoff);
4300 	erase_backoff_by_id(&osd->o_backoffs_by_id, backoff);
4301 	free_backoff(backoff);
4302 
4303 	if (RB_EMPTY_ROOT(&spg->backoffs)) {
4304 		erase_spg_mapping(&osd->o_backoff_mappings, spg);
4305 		free_spg_mapping(spg);
4306 	}
4307 
4308 	for (n = rb_first(&osd->o_requests); n; n = rb_next(n)) {
4309 		struct ceph_osd_request *req =
4310 		    rb_entry(n, struct ceph_osd_request, r_node);
4311 
4312 		if (!ceph_spg_compare(&req->r_t.spgid, &m->spgid)) {
4313 			/*
4314 			 * Match against @m, not @backoff -- the PG may
4315 			 * have split on the OSD.
4316 			 */
4317 			if (target_contained_by(&req->r_t, m->begin, m->end)) {
4318 				/*
4319 				 * If no other installed backoff applies,
4320 				 * resend.
4321 				 */
4322 				send_request(req);
4323 			}
4324 		}
4325 	}
4326 }
4327 
4328 static void handle_backoff(struct ceph_osd *osd, struct ceph_msg *msg)
4329 {
4330 	struct ceph_osd_client *osdc = osd->o_osdc;
4331 	struct MOSDBackoff m;
4332 	int ret;
4333 
4334 	down_read(&osdc->lock);
4335 	if (!osd_registered(osd)) {
4336 		dout("%s osd%d unknown\n", __func__, osd->o_osd);
4337 		up_read(&osdc->lock);
4338 		return;
4339 	}
4340 	WARN_ON(osd->o_osd != le64_to_cpu(msg->hdr.src.num));
4341 
4342 	mutex_lock(&osd->lock);
4343 	ret = decode_MOSDBackoff(msg, &m);
4344 	if (ret) {
4345 		pr_err("failed to decode MOSDBackoff: %d\n", ret);
4346 		ceph_msg_dump(msg);
4347 		goto out_unlock;
4348 	}
4349 
4350 	switch (m.op) {
4351 	case CEPH_OSD_BACKOFF_OP_BLOCK:
4352 		handle_backoff_block(osd, &m);
4353 		break;
4354 	case CEPH_OSD_BACKOFF_OP_UNBLOCK:
4355 		handle_backoff_unblock(osd, &m);
4356 		break;
4357 	default:
4358 		pr_err("%s osd%d unknown op %d\n", __func__, osd->o_osd, m.op);
4359 	}
4360 
4361 	free_hoid(m.begin);
4362 	free_hoid(m.end);
4363 
4364 out_unlock:
4365 	mutex_unlock(&osd->lock);
4366 	up_read(&osdc->lock);
4367 }
4368 
4369 /*
4370  * Process osd watch notifications
4371  */
4372 static void handle_watch_notify(struct ceph_osd_client *osdc,
4373 				struct ceph_msg *msg)
4374 {
4375 	void *p = msg->front.iov_base;
4376 	void *const end = p + msg->front.iov_len;
4377 	struct ceph_osd_linger_request *lreq;
4378 	struct linger_work *lwork;
4379 	u8 proto_ver, opcode;
4380 	u64 cookie, notify_id;
4381 	u64 notifier_id = 0;
4382 	s32 return_code = 0;
4383 	void *payload = NULL;
4384 	u32 payload_len = 0;
4385 
4386 	ceph_decode_8_safe(&p, end, proto_ver, bad);
4387 	ceph_decode_8_safe(&p, end, opcode, bad);
4388 	ceph_decode_64_safe(&p, end, cookie, bad);
4389 	p += 8; /* skip ver */
4390 	ceph_decode_64_safe(&p, end, notify_id, bad);
4391 
4392 	if (proto_ver >= 1) {
4393 		ceph_decode_32_safe(&p, end, payload_len, bad);
4394 		ceph_decode_need(&p, end, payload_len, bad);
4395 		payload = p;
4396 		p += payload_len;
4397 	}
4398 
4399 	if (le16_to_cpu(msg->hdr.version) >= 2)
4400 		ceph_decode_32_safe(&p, end, return_code, bad);
4401 
4402 	if (le16_to_cpu(msg->hdr.version) >= 3)
4403 		ceph_decode_64_safe(&p, end, notifier_id, bad);
4404 
4405 	down_read(&osdc->lock);
4406 	lreq = lookup_linger_osdc(&osdc->linger_requests, cookie);
4407 	if (!lreq) {
4408 		dout("%s opcode %d cookie %llu dne\n", __func__, opcode,
4409 		     cookie);
4410 		goto out_unlock_osdc;
4411 	}
4412 
4413 	mutex_lock(&lreq->lock);
4414 	dout("%s opcode %d cookie %llu lreq %p is_watch %d\n", __func__,
4415 	     opcode, cookie, lreq, lreq->is_watch);
4416 	if (opcode == CEPH_WATCH_EVENT_DISCONNECT) {
4417 		if (!lreq->last_error) {
4418 			lreq->last_error = -ENOTCONN;
4419 			queue_watch_error(lreq);
4420 		}
4421 	} else if (!lreq->is_watch) {
4422 		/* CEPH_WATCH_EVENT_NOTIFY_COMPLETE */
4423 		if (lreq->notify_id && lreq->notify_id != notify_id) {
4424 			dout("lreq %p notify_id %llu != %llu, ignoring\n", lreq,
4425 			     lreq->notify_id, notify_id);
4426 		} else if (!completion_done(&lreq->notify_finish_wait)) {
4427 			struct ceph_msg_data *data =
4428 			    msg->num_data_items ? &msg->data[0] : NULL;
4429 
4430 			if (data) {
4431 				if (lreq->preply_pages) {
4432 					WARN_ON(data->type !=
4433 							CEPH_MSG_DATA_PAGES);
4434 					*lreq->preply_pages = data->pages;
4435 					*lreq->preply_len = data->length;
4436 					data->own_pages = false;
4437 				}
4438 			}
4439 			lreq->notify_finish_error = return_code;
4440 			complete_all(&lreq->notify_finish_wait);
4441 		}
4442 	} else {
4443 		/* CEPH_WATCH_EVENT_NOTIFY */
4444 		lwork = lwork_alloc(lreq, do_watch_notify);
4445 		if (!lwork) {
4446 			pr_err("failed to allocate notify-lwork\n");
4447 			goto out_unlock_lreq;
4448 		}
4449 
4450 		lwork->notify.notify_id = notify_id;
4451 		lwork->notify.notifier_id = notifier_id;
4452 		lwork->notify.payload = payload;
4453 		lwork->notify.payload_len = payload_len;
4454 		lwork->notify.msg = ceph_msg_get(msg);
4455 		lwork_queue(lwork);
4456 	}
4457 
4458 out_unlock_lreq:
4459 	mutex_unlock(&lreq->lock);
4460 out_unlock_osdc:
4461 	up_read(&osdc->lock);
4462 	return;
4463 
4464 bad:
4465 	pr_err("osdc handle_watch_notify corrupt msg\n");
4466 }
4467 
4468 /*
4469  * Register request, send initial attempt.
4470  */
4471 int ceph_osdc_start_request(struct ceph_osd_client *osdc,
4472 			    struct ceph_osd_request *req,
4473 			    bool nofail)
4474 {
4475 	down_read(&osdc->lock);
4476 	submit_request(req, false);
4477 	up_read(&osdc->lock);
4478 
4479 	return 0;
4480 }
4481 EXPORT_SYMBOL(ceph_osdc_start_request);
4482 
4483 /*
4484  * Unregister a registered request.  The request is not completed:
4485  * ->r_result isn't set and __complete_request() isn't called.
4486  */
4487 void ceph_osdc_cancel_request(struct ceph_osd_request *req)
4488 {
4489 	struct ceph_osd_client *osdc = req->r_osdc;
4490 
4491 	down_write(&osdc->lock);
4492 	if (req->r_osd)
4493 		cancel_request(req);
4494 	up_write(&osdc->lock);
4495 }
4496 EXPORT_SYMBOL(ceph_osdc_cancel_request);
4497 
4498 /*
4499  * @timeout: in jiffies, 0 means "wait forever"
4500  */
4501 static int wait_request_timeout(struct ceph_osd_request *req,
4502 				unsigned long timeout)
4503 {
4504 	long left;
4505 
4506 	dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
4507 	left = wait_for_completion_killable_timeout(&req->r_completion,
4508 						ceph_timeout_jiffies(timeout));
4509 	if (left <= 0) {
4510 		left = left ?: -ETIMEDOUT;
4511 		ceph_osdc_cancel_request(req);
4512 	} else {
4513 		left = req->r_result; /* completed */
4514 	}
4515 
4516 	return left;
4517 }
4518 
4519 /*
4520  * wait for a request to complete
4521  */
4522 int ceph_osdc_wait_request(struct ceph_osd_client *osdc,
4523 			   struct ceph_osd_request *req)
4524 {
4525 	return wait_request_timeout(req, 0);
4526 }
4527 EXPORT_SYMBOL(ceph_osdc_wait_request);
4528 
4529 /*
4530  * sync - wait for all in-flight requests to flush.  avoid starvation.
4531  */
4532 void ceph_osdc_sync(struct ceph_osd_client *osdc)
4533 {
4534 	struct rb_node *n, *p;
4535 	u64 last_tid = atomic64_read(&osdc->last_tid);
4536 
4537 again:
4538 	down_read(&osdc->lock);
4539 	for (n = rb_first(&osdc->osds); n; n = rb_next(n)) {
4540 		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
4541 
4542 		mutex_lock(&osd->lock);
4543 		for (p = rb_first(&osd->o_requests); p; p = rb_next(p)) {
4544 			struct ceph_osd_request *req =
4545 			    rb_entry(p, struct ceph_osd_request, r_node);
4546 
4547 			if (req->r_tid > last_tid)
4548 				break;
4549 
4550 			if (!(req->r_flags & CEPH_OSD_FLAG_WRITE))
4551 				continue;
4552 
4553 			ceph_osdc_get_request(req);
4554 			mutex_unlock(&osd->lock);
4555 			up_read(&osdc->lock);
4556 			dout("%s waiting on req %p tid %llu last_tid %llu\n",
4557 			     __func__, req, req->r_tid, last_tid);
4558 			wait_for_completion(&req->r_completion);
4559 			ceph_osdc_put_request(req);
4560 			goto again;
4561 		}
4562 
4563 		mutex_unlock(&osd->lock);
4564 	}
4565 
4566 	up_read(&osdc->lock);
4567 	dout("%s done last_tid %llu\n", __func__, last_tid);
4568 }
4569 EXPORT_SYMBOL(ceph_osdc_sync);
4570 
4571 static struct ceph_osd_request *
4572 alloc_linger_request(struct ceph_osd_linger_request *lreq)
4573 {
4574 	struct ceph_osd_request *req;
4575 
4576 	req = ceph_osdc_alloc_request(lreq->osdc, NULL, 1, false, GFP_NOIO);
4577 	if (!req)
4578 		return NULL;
4579 
4580 	ceph_oid_copy(&req->r_base_oid, &lreq->t.base_oid);
4581 	ceph_oloc_copy(&req->r_base_oloc, &lreq->t.base_oloc);
4582 	return req;
4583 }
4584 
4585 static struct ceph_osd_request *
4586 alloc_watch_request(struct ceph_osd_linger_request *lreq, u8 watch_opcode)
4587 {
4588 	struct ceph_osd_request *req;
4589 
4590 	req = alloc_linger_request(lreq);
4591 	if (!req)
4592 		return NULL;
4593 
4594 	/*
4595 	 * Pass 0 for cookie because we don't know it yet, it will be
4596 	 * filled in by linger_submit().
4597 	 */
4598 	osd_req_op_watch_init(req, 0, 0, watch_opcode);
4599 
4600 	if (ceph_osdc_alloc_messages(req, GFP_NOIO)) {
4601 		ceph_osdc_put_request(req);
4602 		return NULL;
4603 	}
4604 
4605 	return req;
4606 }
4607 
4608 /*
4609  * Returns a handle, caller owns a ref.
4610  */
4611 struct ceph_osd_linger_request *
4612 ceph_osdc_watch(struct ceph_osd_client *osdc,
4613 		struct ceph_object_id *oid,
4614 		struct ceph_object_locator *oloc,
4615 		rados_watchcb2_t wcb,
4616 		rados_watcherrcb_t errcb,
4617 		void *data)
4618 {
4619 	struct ceph_osd_linger_request *lreq;
4620 	int ret;
4621 
4622 	lreq = linger_alloc(osdc);
4623 	if (!lreq)
4624 		return ERR_PTR(-ENOMEM);
4625 
4626 	lreq->is_watch = true;
4627 	lreq->wcb = wcb;
4628 	lreq->errcb = errcb;
4629 	lreq->data = data;
4630 	lreq->watch_valid_thru = jiffies;
4631 
4632 	ceph_oid_copy(&lreq->t.base_oid, oid);
4633 	ceph_oloc_copy(&lreq->t.base_oloc, oloc);
4634 	lreq->t.flags = CEPH_OSD_FLAG_WRITE;
4635 	ktime_get_real_ts64(&lreq->mtime);
4636 
4637 	lreq->reg_req = alloc_watch_request(lreq, CEPH_OSD_WATCH_OP_WATCH);
4638 	if (!lreq->reg_req) {
4639 		ret = -ENOMEM;
4640 		goto err_put_lreq;
4641 	}
4642 
4643 	lreq->ping_req = alloc_watch_request(lreq, CEPH_OSD_WATCH_OP_PING);
4644 	if (!lreq->ping_req) {
4645 		ret = -ENOMEM;
4646 		goto err_put_lreq;
4647 	}
4648 
4649 	linger_submit(lreq);
4650 	ret = linger_reg_commit_wait(lreq);
4651 	if (ret) {
4652 		linger_cancel(lreq);
4653 		goto err_put_lreq;
4654 	}
4655 
4656 	return lreq;
4657 
4658 err_put_lreq:
4659 	linger_put(lreq);
4660 	return ERR_PTR(ret);
4661 }
4662 EXPORT_SYMBOL(ceph_osdc_watch);
4663 
4664 /*
4665  * Releases a ref.
4666  *
4667  * Times out after mount_timeout to preserve rbd unmap behaviour
4668  * introduced in 2894e1d76974 ("rbd: timeout watch teardown on unmap
4669  * with mount_timeout").
4670  */
4671 int ceph_osdc_unwatch(struct ceph_osd_client *osdc,
4672 		      struct ceph_osd_linger_request *lreq)
4673 {
4674 	struct ceph_options *opts = osdc->client->options;
4675 	struct ceph_osd_request *req;
4676 	int ret;
4677 
4678 	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_NOIO);
4679 	if (!req)
4680 		return -ENOMEM;
4681 
4682 	ceph_oid_copy(&req->r_base_oid, &lreq->t.base_oid);
4683 	ceph_oloc_copy(&req->r_base_oloc, &lreq->t.base_oloc);
4684 	req->r_flags = CEPH_OSD_FLAG_WRITE;
4685 	ktime_get_real_ts64(&req->r_mtime);
4686 	osd_req_op_watch_init(req, 0, lreq->linger_id,
4687 			      CEPH_OSD_WATCH_OP_UNWATCH);
4688 
4689 	ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
4690 	if (ret)
4691 		goto out_put_req;
4692 
4693 	ceph_osdc_start_request(osdc, req, false);
4694 	linger_cancel(lreq);
4695 	linger_put(lreq);
4696 	ret = wait_request_timeout(req, opts->mount_timeout);
4697 
4698 out_put_req:
4699 	ceph_osdc_put_request(req);
4700 	return ret;
4701 }
4702 EXPORT_SYMBOL(ceph_osdc_unwatch);
4703 
4704 static int osd_req_op_notify_ack_init(struct ceph_osd_request *req, int which,
4705 				      u64 notify_id, u64 cookie, void *payload,
4706 				      u32 payload_len)
4707 {
4708 	struct ceph_osd_req_op *op;
4709 	struct ceph_pagelist *pl;
4710 	int ret;
4711 
4712 	op = _osd_req_op_init(req, which, CEPH_OSD_OP_NOTIFY_ACK, 0);
4713 
4714 	pl = ceph_pagelist_alloc(GFP_NOIO);
4715 	if (!pl)
4716 		return -ENOMEM;
4717 
4718 	ret = ceph_pagelist_encode_64(pl, notify_id);
4719 	ret |= ceph_pagelist_encode_64(pl, cookie);
4720 	if (payload) {
4721 		ret |= ceph_pagelist_encode_32(pl, payload_len);
4722 		ret |= ceph_pagelist_append(pl, payload, payload_len);
4723 	} else {
4724 		ret |= ceph_pagelist_encode_32(pl, 0);
4725 	}
4726 	if (ret) {
4727 		ceph_pagelist_release(pl);
4728 		return -ENOMEM;
4729 	}
4730 
4731 	ceph_osd_data_pagelist_init(&op->notify_ack.request_data, pl);
4732 	op->indata_len = pl->length;
4733 	return 0;
4734 }
4735 
4736 int ceph_osdc_notify_ack(struct ceph_osd_client *osdc,
4737 			 struct ceph_object_id *oid,
4738 			 struct ceph_object_locator *oloc,
4739 			 u64 notify_id,
4740 			 u64 cookie,
4741 			 void *payload,
4742 			 u32 payload_len)
4743 {
4744 	struct ceph_osd_request *req;
4745 	int ret;
4746 
4747 	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_NOIO);
4748 	if (!req)
4749 		return -ENOMEM;
4750 
4751 	ceph_oid_copy(&req->r_base_oid, oid);
4752 	ceph_oloc_copy(&req->r_base_oloc, oloc);
4753 	req->r_flags = CEPH_OSD_FLAG_READ;
4754 
4755 	ret = osd_req_op_notify_ack_init(req, 0, notify_id, cookie, payload,
4756 					 payload_len);
4757 	if (ret)
4758 		goto out_put_req;
4759 
4760 	ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
4761 	if (ret)
4762 		goto out_put_req;
4763 
4764 	ceph_osdc_start_request(osdc, req, false);
4765 	ret = ceph_osdc_wait_request(osdc, req);
4766 
4767 out_put_req:
4768 	ceph_osdc_put_request(req);
4769 	return ret;
4770 }
4771 EXPORT_SYMBOL(ceph_osdc_notify_ack);
4772 
4773 static int osd_req_op_notify_init(struct ceph_osd_request *req, int which,
4774 				  u64 cookie, u32 prot_ver, u32 timeout,
4775 				  void *payload, u32 payload_len)
4776 {
4777 	struct ceph_osd_req_op *op;
4778 	struct ceph_pagelist *pl;
4779 	int ret;
4780 
4781 	op = _osd_req_op_init(req, which, CEPH_OSD_OP_NOTIFY, 0);
4782 	op->notify.cookie = cookie;
4783 
4784 	pl = ceph_pagelist_alloc(GFP_NOIO);
4785 	if (!pl)
4786 		return -ENOMEM;
4787 
4788 	ret = ceph_pagelist_encode_32(pl, 1); /* prot_ver */
4789 	ret |= ceph_pagelist_encode_32(pl, timeout);
4790 	ret |= ceph_pagelist_encode_32(pl, payload_len);
4791 	ret |= ceph_pagelist_append(pl, payload, payload_len);
4792 	if (ret) {
4793 		ceph_pagelist_release(pl);
4794 		return -ENOMEM;
4795 	}
4796 
4797 	ceph_osd_data_pagelist_init(&op->notify.request_data, pl);
4798 	op->indata_len = pl->length;
4799 	return 0;
4800 }
4801 
4802 /*
4803  * @timeout: in seconds
4804  *
4805  * @preply_{pages,len} are initialized both on success and error.
4806  * The caller is responsible for:
4807  *
4808  *     ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len))
4809  */
4810 int ceph_osdc_notify(struct ceph_osd_client *osdc,
4811 		     struct ceph_object_id *oid,
4812 		     struct ceph_object_locator *oloc,
4813 		     void *payload,
4814 		     u32 payload_len,
4815 		     u32 timeout,
4816 		     struct page ***preply_pages,
4817 		     size_t *preply_len)
4818 {
4819 	struct ceph_osd_linger_request *lreq;
4820 	struct page **pages;
4821 	int ret;
4822 
4823 	WARN_ON(!timeout);
4824 	if (preply_pages) {
4825 		*preply_pages = NULL;
4826 		*preply_len = 0;
4827 	}
4828 
4829 	lreq = linger_alloc(osdc);
4830 	if (!lreq)
4831 		return -ENOMEM;
4832 
4833 	lreq->preply_pages = preply_pages;
4834 	lreq->preply_len = preply_len;
4835 
4836 	ceph_oid_copy(&lreq->t.base_oid, oid);
4837 	ceph_oloc_copy(&lreq->t.base_oloc, oloc);
4838 	lreq->t.flags = CEPH_OSD_FLAG_READ;
4839 
4840 	lreq->reg_req = alloc_linger_request(lreq);
4841 	if (!lreq->reg_req) {
4842 		ret = -ENOMEM;
4843 		goto out_put_lreq;
4844 	}
4845 
4846 	/*
4847 	 * Pass 0 for cookie because we don't know it yet, it will be
4848 	 * filled in by linger_submit().
4849 	 */
4850 	ret = osd_req_op_notify_init(lreq->reg_req, 0, 0, 1, timeout,
4851 				     payload, payload_len);
4852 	if (ret)
4853 		goto out_put_lreq;
4854 
4855 	/* for notify_id */
4856 	pages = ceph_alloc_page_vector(1, GFP_NOIO);
4857 	if (IS_ERR(pages)) {
4858 		ret = PTR_ERR(pages);
4859 		goto out_put_lreq;
4860 	}
4861 	ceph_osd_data_pages_init(osd_req_op_data(lreq->reg_req, 0, notify,
4862 						 response_data),
4863 				 pages, PAGE_SIZE, 0, false, true);
4864 
4865 	ret = ceph_osdc_alloc_messages(lreq->reg_req, GFP_NOIO);
4866 	if (ret)
4867 		goto out_put_lreq;
4868 
4869 	linger_submit(lreq);
4870 	ret = linger_reg_commit_wait(lreq);
4871 	if (!ret)
4872 		ret = linger_notify_finish_wait(lreq);
4873 	else
4874 		dout("lreq %p failed to initiate notify %d\n", lreq, ret);
4875 
4876 	linger_cancel(lreq);
4877 out_put_lreq:
4878 	linger_put(lreq);
4879 	return ret;
4880 }
4881 EXPORT_SYMBOL(ceph_osdc_notify);
4882 
4883 /*
4884  * Return the number of milliseconds since the watch was last
4885  * confirmed, or an error.  If there is an error, the watch is no
4886  * longer valid, and should be destroyed with ceph_osdc_unwatch().
4887  */
4888 int ceph_osdc_watch_check(struct ceph_osd_client *osdc,
4889 			  struct ceph_osd_linger_request *lreq)
4890 {
4891 	unsigned long stamp, age;
4892 	int ret;
4893 
4894 	down_read(&osdc->lock);
4895 	mutex_lock(&lreq->lock);
4896 	stamp = lreq->watch_valid_thru;
4897 	if (!list_empty(&lreq->pending_lworks)) {
4898 		struct linger_work *lwork =
4899 		    list_first_entry(&lreq->pending_lworks,
4900 				     struct linger_work,
4901 				     pending_item);
4902 
4903 		if (time_before(lwork->queued_stamp, stamp))
4904 			stamp = lwork->queued_stamp;
4905 	}
4906 	age = jiffies - stamp;
4907 	dout("%s lreq %p linger_id %llu age %lu last_error %d\n", __func__,
4908 	     lreq, lreq->linger_id, age, lreq->last_error);
4909 	/* we are truncating to msecs, so return a safe upper bound */
4910 	ret = lreq->last_error ?: 1 + jiffies_to_msecs(age);
4911 
4912 	mutex_unlock(&lreq->lock);
4913 	up_read(&osdc->lock);
4914 	return ret;
4915 }
4916 
4917 static int decode_watcher(void **p, void *end, struct ceph_watch_item *item)
4918 {
4919 	u8 struct_v;
4920 	u32 struct_len;
4921 	int ret;
4922 
4923 	ret = ceph_start_decoding(p, end, 2, "watch_item_t",
4924 				  &struct_v, &struct_len);
4925 	if (ret)
4926 		goto bad;
4927 
4928 	ret = -EINVAL;
4929 	ceph_decode_copy_safe(p, end, &item->name, sizeof(item->name), bad);
4930 	ceph_decode_64_safe(p, end, item->cookie, bad);
4931 	ceph_decode_skip_32(p, end, bad); /* skip timeout seconds */
4932 
4933 	if (struct_v >= 2) {
4934 		ret = ceph_decode_entity_addr(p, end, &item->addr);
4935 		if (ret)
4936 			goto bad;
4937 	} else {
4938 		ret = 0;
4939 	}
4940 
4941 	dout("%s %s%llu cookie %llu addr %s\n", __func__,
4942 	     ENTITY_NAME(item->name), item->cookie,
4943 	     ceph_pr_addr(&item->addr));
4944 bad:
4945 	return ret;
4946 }
4947 
4948 static int decode_watchers(void **p, void *end,
4949 			   struct ceph_watch_item **watchers,
4950 			   u32 *num_watchers)
4951 {
4952 	u8 struct_v;
4953 	u32 struct_len;
4954 	int i;
4955 	int ret;
4956 
4957 	ret = ceph_start_decoding(p, end, 1, "obj_list_watch_response_t",
4958 				  &struct_v, &struct_len);
4959 	if (ret)
4960 		return ret;
4961 
4962 	*num_watchers = ceph_decode_32(p);
4963 	*watchers = kcalloc(*num_watchers, sizeof(**watchers), GFP_NOIO);
4964 	if (!*watchers)
4965 		return -ENOMEM;
4966 
4967 	for (i = 0; i < *num_watchers; i++) {
4968 		ret = decode_watcher(p, end, *watchers + i);
4969 		if (ret) {
4970 			kfree(*watchers);
4971 			return ret;
4972 		}
4973 	}
4974 
4975 	return 0;
4976 }
4977 
4978 /*
4979  * On success, the caller is responsible for:
4980  *
4981  *     kfree(watchers);
4982  */
4983 int ceph_osdc_list_watchers(struct ceph_osd_client *osdc,
4984 			    struct ceph_object_id *oid,
4985 			    struct ceph_object_locator *oloc,
4986 			    struct ceph_watch_item **watchers,
4987 			    u32 *num_watchers)
4988 {
4989 	struct ceph_osd_request *req;
4990 	struct page **pages;
4991 	int ret;
4992 
4993 	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_NOIO);
4994 	if (!req)
4995 		return -ENOMEM;
4996 
4997 	ceph_oid_copy(&req->r_base_oid, oid);
4998 	ceph_oloc_copy(&req->r_base_oloc, oloc);
4999 	req->r_flags = CEPH_OSD_FLAG_READ;
5000 
5001 	pages = ceph_alloc_page_vector(1, GFP_NOIO);
5002 	if (IS_ERR(pages)) {
5003 		ret = PTR_ERR(pages);
5004 		goto out_put_req;
5005 	}
5006 
5007 	osd_req_op_init(req, 0, CEPH_OSD_OP_LIST_WATCHERS, 0);
5008 	ceph_osd_data_pages_init(osd_req_op_data(req, 0, list_watchers,
5009 						 response_data),
5010 				 pages, PAGE_SIZE, 0, false, true);
5011 
5012 	ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
5013 	if (ret)
5014 		goto out_put_req;
5015 
5016 	ceph_osdc_start_request(osdc, req, false);
5017 	ret = ceph_osdc_wait_request(osdc, req);
5018 	if (ret >= 0) {
5019 		void *p = page_address(pages[0]);
5020 		void *const end = p + req->r_ops[0].outdata_len;
5021 
5022 		ret = decode_watchers(&p, end, watchers, num_watchers);
5023 	}
5024 
5025 out_put_req:
5026 	ceph_osdc_put_request(req);
5027 	return ret;
5028 }
5029 EXPORT_SYMBOL(ceph_osdc_list_watchers);
5030 
5031 /*
5032  * Call all pending notify callbacks - for use after a watch is
5033  * unregistered, to make sure no more callbacks for it will be invoked
5034  */
5035 void ceph_osdc_flush_notifies(struct ceph_osd_client *osdc)
5036 {
5037 	dout("%s osdc %p\n", __func__, osdc);
5038 	flush_workqueue(osdc->notify_wq);
5039 }
5040 EXPORT_SYMBOL(ceph_osdc_flush_notifies);
5041 
5042 void ceph_osdc_maybe_request_map(struct ceph_osd_client *osdc)
5043 {
5044 	down_read(&osdc->lock);
5045 	maybe_request_map(osdc);
5046 	up_read(&osdc->lock);
5047 }
5048 EXPORT_SYMBOL(ceph_osdc_maybe_request_map);
5049 
5050 /*
5051  * Execute an OSD class method on an object.
5052  *
5053  * @flags: CEPH_OSD_FLAG_*
5054  * @resp_len: in/out param for reply length
5055  */
5056 int ceph_osdc_call(struct ceph_osd_client *osdc,
5057 		   struct ceph_object_id *oid,
5058 		   struct ceph_object_locator *oloc,
5059 		   const char *class, const char *method,
5060 		   unsigned int flags,
5061 		   struct page *req_page, size_t req_len,
5062 		   struct page **resp_pages, size_t *resp_len)
5063 {
5064 	struct ceph_osd_request *req;
5065 	int ret;
5066 
5067 	if (req_len > PAGE_SIZE)
5068 		return -E2BIG;
5069 
5070 	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_NOIO);
5071 	if (!req)
5072 		return -ENOMEM;
5073 
5074 	ceph_oid_copy(&req->r_base_oid, oid);
5075 	ceph_oloc_copy(&req->r_base_oloc, oloc);
5076 	req->r_flags = flags;
5077 
5078 	ret = osd_req_op_cls_init(req, 0, class, method);
5079 	if (ret)
5080 		goto out_put_req;
5081 
5082 	if (req_page)
5083 		osd_req_op_cls_request_data_pages(req, 0, &req_page, req_len,
5084 						  0, false, false);
5085 	if (resp_pages)
5086 		osd_req_op_cls_response_data_pages(req, 0, resp_pages,
5087 						   *resp_len, 0, false, false);
5088 
5089 	ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
5090 	if (ret)
5091 		goto out_put_req;
5092 
5093 	ceph_osdc_start_request(osdc, req, false);
5094 	ret = ceph_osdc_wait_request(osdc, req);
5095 	if (ret >= 0) {
5096 		ret = req->r_ops[0].rval;
5097 		if (resp_pages)
5098 			*resp_len = req->r_ops[0].outdata_len;
5099 	}
5100 
5101 out_put_req:
5102 	ceph_osdc_put_request(req);
5103 	return ret;
5104 }
5105 EXPORT_SYMBOL(ceph_osdc_call);
5106 
5107 /*
5108  * reset all osd connections
5109  */
5110 void ceph_osdc_reopen_osds(struct ceph_osd_client *osdc)
5111 {
5112 	struct rb_node *n;
5113 
5114 	down_write(&osdc->lock);
5115 	for (n = rb_first(&osdc->osds); n; ) {
5116 		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
5117 
5118 		n = rb_next(n);
5119 		if (!reopen_osd(osd))
5120 			kick_osd_requests(osd);
5121 	}
5122 	up_write(&osdc->lock);
5123 }
5124 
5125 /*
5126  * init, shutdown
5127  */
5128 int ceph_osdc_init(struct ceph_osd_client *osdc, struct ceph_client *client)
5129 {
5130 	int err;
5131 
5132 	dout("init\n");
5133 	osdc->client = client;
5134 	init_rwsem(&osdc->lock);
5135 	osdc->osds = RB_ROOT;
5136 	INIT_LIST_HEAD(&osdc->osd_lru);
5137 	spin_lock_init(&osdc->osd_lru_lock);
5138 	osd_init(&osdc->homeless_osd);
5139 	osdc->homeless_osd.o_osdc = osdc;
5140 	osdc->homeless_osd.o_osd = CEPH_HOMELESS_OSD;
5141 	osdc->last_linger_id = CEPH_LINGER_ID_START;
5142 	osdc->linger_requests = RB_ROOT;
5143 	osdc->map_checks = RB_ROOT;
5144 	osdc->linger_map_checks = RB_ROOT;
5145 	INIT_DELAYED_WORK(&osdc->timeout_work, handle_timeout);
5146 	INIT_DELAYED_WORK(&osdc->osds_timeout_work, handle_osds_timeout);
5147 
5148 	err = -ENOMEM;
5149 	osdc->osdmap = ceph_osdmap_alloc();
5150 	if (!osdc->osdmap)
5151 		goto out;
5152 
5153 	osdc->req_mempool = mempool_create_slab_pool(10,
5154 						     ceph_osd_request_cache);
5155 	if (!osdc->req_mempool)
5156 		goto out_map;
5157 
5158 	err = ceph_msgpool_init(&osdc->msgpool_op, CEPH_MSG_OSD_OP,
5159 				PAGE_SIZE, CEPH_OSD_SLAB_OPS, 10, "osd_op");
5160 	if (err < 0)
5161 		goto out_mempool;
5162 	err = ceph_msgpool_init(&osdc->msgpool_op_reply, CEPH_MSG_OSD_OPREPLY,
5163 				PAGE_SIZE, CEPH_OSD_SLAB_OPS, 10,
5164 				"osd_op_reply");
5165 	if (err < 0)
5166 		goto out_msgpool;
5167 
5168 	err = -ENOMEM;
5169 	osdc->notify_wq = create_singlethread_workqueue("ceph-watch-notify");
5170 	if (!osdc->notify_wq)
5171 		goto out_msgpool_reply;
5172 
5173 	osdc->completion_wq = create_singlethread_workqueue("ceph-completion");
5174 	if (!osdc->completion_wq)
5175 		goto out_notify_wq;
5176 
5177 	schedule_delayed_work(&osdc->timeout_work,
5178 			      osdc->client->options->osd_keepalive_timeout);
5179 	schedule_delayed_work(&osdc->osds_timeout_work,
5180 	    round_jiffies_relative(osdc->client->options->osd_idle_ttl));
5181 
5182 	return 0;
5183 
5184 out_notify_wq:
5185 	destroy_workqueue(osdc->notify_wq);
5186 out_msgpool_reply:
5187 	ceph_msgpool_destroy(&osdc->msgpool_op_reply);
5188 out_msgpool:
5189 	ceph_msgpool_destroy(&osdc->msgpool_op);
5190 out_mempool:
5191 	mempool_destroy(osdc->req_mempool);
5192 out_map:
5193 	ceph_osdmap_destroy(osdc->osdmap);
5194 out:
5195 	return err;
5196 }
5197 
5198 void ceph_osdc_stop(struct ceph_osd_client *osdc)
5199 {
5200 	destroy_workqueue(osdc->completion_wq);
5201 	destroy_workqueue(osdc->notify_wq);
5202 	cancel_delayed_work_sync(&osdc->timeout_work);
5203 	cancel_delayed_work_sync(&osdc->osds_timeout_work);
5204 
5205 	down_write(&osdc->lock);
5206 	while (!RB_EMPTY_ROOT(&osdc->osds)) {
5207 		struct ceph_osd *osd = rb_entry(rb_first(&osdc->osds),
5208 						struct ceph_osd, o_node);
5209 		close_osd(osd);
5210 	}
5211 	up_write(&osdc->lock);
5212 	WARN_ON(refcount_read(&osdc->homeless_osd.o_ref) != 1);
5213 	osd_cleanup(&osdc->homeless_osd);
5214 
5215 	WARN_ON(!list_empty(&osdc->osd_lru));
5216 	WARN_ON(!RB_EMPTY_ROOT(&osdc->linger_requests));
5217 	WARN_ON(!RB_EMPTY_ROOT(&osdc->map_checks));
5218 	WARN_ON(!RB_EMPTY_ROOT(&osdc->linger_map_checks));
5219 	WARN_ON(atomic_read(&osdc->num_requests));
5220 	WARN_ON(atomic_read(&osdc->num_homeless));
5221 
5222 	ceph_osdmap_destroy(osdc->osdmap);
5223 	mempool_destroy(osdc->req_mempool);
5224 	ceph_msgpool_destroy(&osdc->msgpool_op);
5225 	ceph_msgpool_destroy(&osdc->msgpool_op_reply);
5226 }
5227 
5228 static int osd_req_op_copy_from_init(struct ceph_osd_request *req,
5229 				     u64 src_snapid, u64 src_version,
5230 				     struct ceph_object_id *src_oid,
5231 				     struct ceph_object_locator *src_oloc,
5232 				     u32 src_fadvise_flags,
5233 				     u32 dst_fadvise_flags,
5234 				     u32 truncate_seq, u64 truncate_size,
5235 				     u8 copy_from_flags)
5236 {
5237 	struct ceph_osd_req_op *op;
5238 	struct page **pages;
5239 	void *p, *end;
5240 
5241 	pages = ceph_alloc_page_vector(1, GFP_KERNEL);
5242 	if (IS_ERR(pages))
5243 		return PTR_ERR(pages);
5244 
5245 	op = _osd_req_op_init(req, 0, CEPH_OSD_OP_COPY_FROM2,
5246 			      dst_fadvise_flags);
5247 	op->copy_from.snapid = src_snapid;
5248 	op->copy_from.src_version = src_version;
5249 	op->copy_from.flags = copy_from_flags;
5250 	op->copy_from.src_fadvise_flags = src_fadvise_flags;
5251 
5252 	p = page_address(pages[0]);
5253 	end = p + PAGE_SIZE;
5254 	ceph_encode_string(&p, end, src_oid->name, src_oid->name_len);
5255 	encode_oloc(&p, end, src_oloc);
5256 	ceph_encode_32(&p, truncate_seq);
5257 	ceph_encode_64(&p, truncate_size);
5258 	op->indata_len = PAGE_SIZE - (end - p);
5259 
5260 	ceph_osd_data_pages_init(&op->copy_from.osd_data, pages,
5261 				 op->indata_len, 0, false, true);
5262 	return 0;
5263 }
5264 
5265 int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
5266 			u64 src_snapid, u64 src_version,
5267 			struct ceph_object_id *src_oid,
5268 			struct ceph_object_locator *src_oloc,
5269 			u32 src_fadvise_flags,
5270 			struct ceph_object_id *dst_oid,
5271 			struct ceph_object_locator *dst_oloc,
5272 			u32 dst_fadvise_flags,
5273 			u32 truncate_seq, u64 truncate_size,
5274 			u8 copy_from_flags)
5275 {
5276 	struct ceph_osd_request *req;
5277 	int ret;
5278 
5279 	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL);
5280 	if (!req)
5281 		return -ENOMEM;
5282 
5283 	req->r_flags = CEPH_OSD_FLAG_WRITE;
5284 
5285 	ceph_oloc_copy(&req->r_t.base_oloc, dst_oloc);
5286 	ceph_oid_copy(&req->r_t.base_oid, dst_oid);
5287 
5288 	ret = osd_req_op_copy_from_init(req, src_snapid, src_version, src_oid,
5289 					src_oloc, src_fadvise_flags,
5290 					dst_fadvise_flags, truncate_seq,
5291 					truncate_size, copy_from_flags);
5292 	if (ret)
5293 		goto out;
5294 
5295 	ret = ceph_osdc_alloc_messages(req, GFP_KERNEL);
5296 	if (ret)
5297 		goto out;
5298 
5299 	ceph_osdc_start_request(osdc, req, false);
5300 	ret = ceph_osdc_wait_request(osdc, req);
5301 
5302 out:
5303 	ceph_osdc_put_request(req);
5304 	return ret;
5305 }
5306 EXPORT_SYMBOL(ceph_osdc_copy_from);
5307 
5308 int __init ceph_osdc_setup(void)
5309 {
5310 	size_t size = sizeof(struct ceph_osd_request) +
5311 	    CEPH_OSD_SLAB_OPS * sizeof(struct ceph_osd_req_op);
5312 
5313 	BUG_ON(ceph_osd_request_cache);
5314 	ceph_osd_request_cache = kmem_cache_create("ceph_osd_request", size,
5315 						   0, 0, NULL);
5316 
5317 	return ceph_osd_request_cache ? 0 : -ENOMEM;
5318 }
5319 
5320 void ceph_osdc_cleanup(void)
5321 {
5322 	BUG_ON(!ceph_osd_request_cache);
5323 	kmem_cache_destroy(ceph_osd_request_cache);
5324 	ceph_osd_request_cache = NULL;
5325 }
5326 
5327 /*
5328  * handle incoming message
5329  */
5330 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
5331 {
5332 	struct ceph_osd *osd = con->private;
5333 	struct ceph_osd_client *osdc = osd->o_osdc;
5334 	int type = le16_to_cpu(msg->hdr.type);
5335 
5336 	switch (type) {
5337 	case CEPH_MSG_OSD_MAP:
5338 		ceph_osdc_handle_map(osdc, msg);
5339 		break;
5340 	case CEPH_MSG_OSD_OPREPLY:
5341 		handle_reply(osd, msg);
5342 		break;
5343 	case CEPH_MSG_OSD_BACKOFF:
5344 		handle_backoff(osd, msg);
5345 		break;
5346 	case CEPH_MSG_WATCH_NOTIFY:
5347 		handle_watch_notify(osdc, msg);
5348 		break;
5349 
5350 	default:
5351 		pr_err("received unknown message type %d %s\n", type,
5352 		       ceph_msg_type_name(type));
5353 	}
5354 
5355 	ceph_msg_put(msg);
5356 }
5357 
5358 /*
5359  * Lookup and return message for incoming reply.  Don't try to do
5360  * anything about a larger than preallocated data portion of the
5361  * message at the moment - for now, just skip the message.
5362  */
5363 static struct ceph_msg *get_reply(struct ceph_connection *con,
5364 				  struct ceph_msg_header *hdr,
5365 				  int *skip)
5366 {
5367 	struct ceph_osd *osd = con->private;
5368 	struct ceph_osd_client *osdc = osd->o_osdc;
5369 	struct ceph_msg *m = NULL;
5370 	struct ceph_osd_request *req;
5371 	int front_len = le32_to_cpu(hdr->front_len);
5372 	int data_len = le32_to_cpu(hdr->data_len);
5373 	u64 tid = le64_to_cpu(hdr->tid);
5374 
5375 	down_read(&osdc->lock);
5376 	if (!osd_registered(osd)) {
5377 		dout("%s osd%d unknown, skipping\n", __func__, osd->o_osd);
5378 		*skip = 1;
5379 		goto out_unlock_osdc;
5380 	}
5381 	WARN_ON(osd->o_osd != le64_to_cpu(hdr->src.num));
5382 
5383 	mutex_lock(&osd->lock);
5384 	req = lookup_request(&osd->o_requests, tid);
5385 	if (!req) {
5386 		dout("%s osd%d tid %llu unknown, skipping\n", __func__,
5387 		     osd->o_osd, tid);
5388 		*skip = 1;
5389 		goto out_unlock_session;
5390 	}
5391 
5392 	ceph_msg_revoke_incoming(req->r_reply);
5393 
5394 	if (front_len > req->r_reply->front_alloc_len) {
5395 		pr_warn("%s osd%d tid %llu front %d > preallocated %d\n",
5396 			__func__, osd->o_osd, req->r_tid, front_len,
5397 			req->r_reply->front_alloc_len);
5398 		m = ceph_msg_new(CEPH_MSG_OSD_OPREPLY, front_len, GFP_NOFS,
5399 				 false);
5400 		if (!m)
5401 			goto out_unlock_session;
5402 		ceph_msg_put(req->r_reply);
5403 		req->r_reply = m;
5404 	}
5405 
5406 	if (data_len > req->r_reply->data_length) {
5407 		pr_warn("%s osd%d tid %llu data %d > preallocated %zu, skipping\n",
5408 			__func__, osd->o_osd, req->r_tid, data_len,
5409 			req->r_reply->data_length);
5410 		m = NULL;
5411 		*skip = 1;
5412 		goto out_unlock_session;
5413 	}
5414 
5415 	m = ceph_msg_get(req->r_reply);
5416 	dout("get_reply tid %lld %p\n", tid, m);
5417 
5418 out_unlock_session:
5419 	mutex_unlock(&osd->lock);
5420 out_unlock_osdc:
5421 	up_read(&osdc->lock);
5422 	return m;
5423 }
5424 
5425 static struct ceph_msg *alloc_msg_with_page_vector(struct ceph_msg_header *hdr)
5426 {
5427 	struct ceph_msg *m;
5428 	int type = le16_to_cpu(hdr->type);
5429 	u32 front_len = le32_to_cpu(hdr->front_len);
5430 	u32 data_len = le32_to_cpu(hdr->data_len);
5431 
5432 	m = ceph_msg_new2(type, front_len, 1, GFP_NOIO, false);
5433 	if (!m)
5434 		return NULL;
5435 
5436 	if (data_len) {
5437 		struct page **pages;
5438 
5439 		pages = ceph_alloc_page_vector(calc_pages_for(0, data_len),
5440 					       GFP_NOIO);
5441 		if (IS_ERR(pages)) {
5442 			ceph_msg_put(m);
5443 			return NULL;
5444 		}
5445 
5446 		ceph_msg_data_add_pages(m, pages, data_len, 0, true);
5447 	}
5448 
5449 	return m;
5450 }
5451 
5452 static struct ceph_msg *alloc_msg(struct ceph_connection *con,
5453 				  struct ceph_msg_header *hdr,
5454 				  int *skip)
5455 {
5456 	struct ceph_osd *osd = con->private;
5457 	int type = le16_to_cpu(hdr->type);
5458 
5459 	*skip = 0;
5460 	switch (type) {
5461 	case CEPH_MSG_OSD_MAP:
5462 	case CEPH_MSG_OSD_BACKOFF:
5463 	case CEPH_MSG_WATCH_NOTIFY:
5464 		return alloc_msg_with_page_vector(hdr);
5465 	case CEPH_MSG_OSD_OPREPLY:
5466 		return get_reply(con, hdr, skip);
5467 	default:
5468 		pr_warn("%s osd%d unknown msg type %d, skipping\n", __func__,
5469 			osd->o_osd, type);
5470 		*skip = 1;
5471 		return NULL;
5472 	}
5473 }
5474 
5475 /*
5476  * Wrappers to refcount containing ceph_osd struct
5477  */
5478 static struct ceph_connection *get_osd_con(struct ceph_connection *con)
5479 {
5480 	struct ceph_osd *osd = con->private;
5481 	if (get_osd(osd))
5482 		return con;
5483 	return NULL;
5484 }
5485 
5486 static void put_osd_con(struct ceph_connection *con)
5487 {
5488 	struct ceph_osd *osd = con->private;
5489 	put_osd(osd);
5490 }
5491 
5492 /*
5493  * authentication
5494  */
5495 /*
5496  * Note: returned pointer is the address of a structure that's
5497  * managed separately.  Caller must *not* attempt to free it.
5498  */
5499 static struct ceph_auth_handshake *get_authorizer(struct ceph_connection *con,
5500 					int *proto, int force_new)
5501 {
5502 	struct ceph_osd *o = con->private;
5503 	struct ceph_osd_client *osdc = o->o_osdc;
5504 	struct ceph_auth_client *ac = osdc->client->monc.auth;
5505 	struct ceph_auth_handshake *auth = &o->o_auth;
5506 
5507 	if (force_new && auth->authorizer) {
5508 		ceph_auth_destroy_authorizer(auth->authorizer);
5509 		auth->authorizer = NULL;
5510 	}
5511 	if (!auth->authorizer) {
5512 		int ret = ceph_auth_create_authorizer(ac, CEPH_ENTITY_TYPE_OSD,
5513 						      auth);
5514 		if (ret)
5515 			return ERR_PTR(ret);
5516 	} else {
5517 		int ret = ceph_auth_update_authorizer(ac, CEPH_ENTITY_TYPE_OSD,
5518 						     auth);
5519 		if (ret)
5520 			return ERR_PTR(ret);
5521 	}
5522 	*proto = ac->protocol;
5523 
5524 	return auth;
5525 }
5526 
5527 static int add_authorizer_challenge(struct ceph_connection *con,
5528 				    void *challenge_buf, int challenge_buf_len)
5529 {
5530 	struct ceph_osd *o = con->private;
5531 	struct ceph_osd_client *osdc = o->o_osdc;
5532 	struct ceph_auth_client *ac = osdc->client->monc.auth;
5533 
5534 	return ceph_auth_add_authorizer_challenge(ac, o->o_auth.authorizer,
5535 					    challenge_buf, challenge_buf_len);
5536 }
5537 
5538 static int verify_authorizer_reply(struct ceph_connection *con)
5539 {
5540 	struct ceph_osd *o = con->private;
5541 	struct ceph_osd_client *osdc = o->o_osdc;
5542 	struct ceph_auth_client *ac = osdc->client->monc.auth;
5543 
5544 	return ceph_auth_verify_authorizer_reply(ac, o->o_auth.authorizer);
5545 }
5546 
5547 static int invalidate_authorizer(struct ceph_connection *con)
5548 {
5549 	struct ceph_osd *o = con->private;
5550 	struct ceph_osd_client *osdc = o->o_osdc;
5551 	struct ceph_auth_client *ac = osdc->client->monc.auth;
5552 
5553 	ceph_auth_invalidate_authorizer(ac, CEPH_ENTITY_TYPE_OSD);
5554 	return ceph_monc_validate_auth(&osdc->client->monc);
5555 }
5556 
5557 static void osd_reencode_message(struct ceph_msg *msg)
5558 {
5559 	int type = le16_to_cpu(msg->hdr.type);
5560 
5561 	if (type == CEPH_MSG_OSD_OP)
5562 		encode_request_finish(msg);
5563 }
5564 
5565 static int osd_sign_message(struct ceph_msg *msg)
5566 {
5567 	struct ceph_osd *o = msg->con->private;
5568 	struct ceph_auth_handshake *auth = &o->o_auth;
5569 
5570 	return ceph_auth_sign_message(auth, msg);
5571 }
5572 
5573 static int osd_check_message_signature(struct ceph_msg *msg)
5574 {
5575 	struct ceph_osd *o = msg->con->private;
5576 	struct ceph_auth_handshake *auth = &o->o_auth;
5577 
5578 	return ceph_auth_check_message_signature(auth, msg);
5579 }
5580 
5581 static const struct ceph_connection_operations osd_con_ops = {
5582 	.get = get_osd_con,
5583 	.put = put_osd_con,
5584 	.dispatch = dispatch,
5585 	.get_authorizer = get_authorizer,
5586 	.add_authorizer_challenge = add_authorizer_challenge,
5587 	.verify_authorizer_reply = verify_authorizer_reply,
5588 	.invalidate_authorizer = invalidate_authorizer,
5589 	.alloc_msg = alloc_msg,
5590 	.reencode_message = osd_reencode_message,
5591 	.sign_message = osd_sign_message,
5592 	.check_message_signature = osd_check_message_signature,
5593 	.fault = osd_fault,
5594 };
5595