xref: /linux/fs/nfs/callback_proc.c (revision 12871a0bd67dd4db4418e1daafcd46e9d329ef10)
1 /*
2  * linux/fs/nfs/callback_proc.c
3  *
4  * Copyright (C) 2004 Trond Myklebust
5  *
6  * NFSv4 callback procedures
7  */
8 #include <linux/nfs4.h>
9 #include <linux/nfs_fs.h>
10 #include <linux/slab.h>
11 #include "nfs4_fs.h"
12 #include "callback.h"
13 #include "delegation.h"
14 #include "internal.h"
15 #include "pnfs.h"
16 
17 #ifdef NFS_DEBUG
18 #define NFSDBG_FACILITY NFSDBG_CALLBACK
19 #endif
20 
21 __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
22 			     struct cb_getattrres *res,
23 			     struct cb_process_state *cps)
24 {
25 	struct nfs_delegation *delegation;
26 	struct nfs_inode *nfsi;
27 	struct inode *inode;
28 
29 	res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
30 	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
31 		goto out;
32 
33 	res->bitmap[0] = res->bitmap[1] = 0;
34 	res->status = htonl(NFS4ERR_BADHANDLE);
35 
36 	dprintk("NFS: GETATTR callback request from %s\n",
37 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
38 
39 	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
40 	if (inode == NULL)
41 		goto out;
42 	nfsi = NFS_I(inode);
43 	rcu_read_lock();
44 	delegation = rcu_dereference(nfsi->delegation);
45 	if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
46 		goto out_iput;
47 	res->size = i_size_read(inode);
48 	res->change_attr = delegation->change_attr;
49 	if (nfsi->npages != 0)
50 		res->change_attr++;
51 	res->ctime = inode->i_ctime;
52 	res->mtime = inode->i_mtime;
53 	res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
54 		args->bitmap[0];
55 	res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
56 		args->bitmap[1];
57 	res->status = 0;
58 out_iput:
59 	rcu_read_unlock();
60 	iput(inode);
61 out:
62 	dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
63 	return res->status;
64 }
65 
66 __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
67 			    struct cb_process_state *cps)
68 {
69 	struct inode *inode;
70 	__be32 res;
71 
72 	res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
73 	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
74 		goto out;
75 
76 	dprintk("NFS: RECALL callback request from %s\n",
77 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
78 
79 	res = htonl(NFS4ERR_BADHANDLE);
80 	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
81 	if (inode == NULL)
82 		goto out;
83 	/* Set up a helper thread to actually return the delegation */
84 	switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
85 	case 0:
86 		res = 0;
87 		break;
88 	case -ENOENT:
89 		if (res != 0)
90 			res = htonl(NFS4ERR_BAD_STATEID);
91 		break;
92 	default:
93 		res = htonl(NFS4ERR_RESOURCE);
94 	}
95 	iput(inode);
96 out:
97 	dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
98 	return res;
99 }
100 
101 int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation, const nfs4_stateid *stateid)
102 {
103 	if (delegation == NULL || memcmp(delegation->stateid.data, stateid->data,
104 					 sizeof(delegation->stateid.data)) != 0)
105 		return 0;
106 	return 1;
107 }
108 
109 #if defined(CONFIG_NFS_V4_1)
110 
111 static u32 initiate_file_draining(struct nfs_client *clp,
112 				  struct cb_layoutrecallargs *args)
113 {
114 	struct pnfs_layout_hdr *lo;
115 	struct inode *ino;
116 	bool found = false;
117 	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
118 	LIST_HEAD(free_me_list);
119 
120 	spin_lock(&clp->cl_lock);
121 	list_for_each_entry(lo, &clp->cl_layouts, plh_layouts) {
122 		if (nfs_compare_fh(&args->cbl_fh,
123 				   &NFS_I(lo->plh_inode)->fh))
124 			continue;
125 		ino = igrab(lo->plh_inode);
126 		if (!ino)
127 			continue;
128 		found = true;
129 		/* Without this, layout can be freed as soon
130 		 * as we release cl_lock.
131 		 */
132 		get_layout_hdr(lo);
133 		break;
134 	}
135 	spin_unlock(&clp->cl_lock);
136 	if (!found)
137 		return NFS4ERR_NOMATCHING_LAYOUT;
138 
139 	spin_lock(&ino->i_lock);
140 	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
141 	    mark_matching_lsegs_invalid(lo, &free_me_list,
142 					&args->cbl_range))
143 		rv = NFS4ERR_DELAY;
144 	else
145 		rv = NFS4ERR_NOMATCHING_LAYOUT;
146 	pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
147 	spin_unlock(&ino->i_lock);
148 	pnfs_free_lseg_list(&free_me_list);
149 	put_layout_hdr(lo);
150 	iput(ino);
151 	return rv;
152 }
153 
154 static u32 initiate_bulk_draining(struct nfs_client *clp,
155 				  struct cb_layoutrecallargs *args)
156 {
157 	struct pnfs_layout_hdr *lo;
158 	struct inode *ino;
159 	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
160 	struct pnfs_layout_hdr *tmp;
161 	LIST_HEAD(recall_list);
162 	LIST_HEAD(free_me_list);
163 	struct pnfs_layout_range range = {
164 		.iomode = IOMODE_ANY,
165 		.offset = 0,
166 		.length = NFS4_MAX_UINT64,
167 	};
168 
169 	spin_lock(&clp->cl_lock);
170 	list_for_each_entry(lo, &clp->cl_layouts, plh_layouts) {
171 		if ((args->cbl_recall_type == RETURN_FSID) &&
172 		    memcmp(&NFS_SERVER(lo->plh_inode)->fsid,
173 			   &args->cbl_fsid, sizeof(struct nfs_fsid)))
174 			continue;
175 		if (!igrab(lo->plh_inode))
176 			continue;
177 		get_layout_hdr(lo);
178 		BUG_ON(!list_empty(&lo->plh_bulk_recall));
179 		list_add(&lo->plh_bulk_recall, &recall_list);
180 	}
181 	spin_unlock(&clp->cl_lock);
182 	list_for_each_entry_safe(lo, tmp,
183 				 &recall_list, plh_bulk_recall) {
184 		ino = lo->plh_inode;
185 		spin_lock(&ino->i_lock);
186 		set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
187 		if (mark_matching_lsegs_invalid(lo, &free_me_list, &range))
188 			rv = NFS4ERR_DELAY;
189 		list_del_init(&lo->plh_bulk_recall);
190 		spin_unlock(&ino->i_lock);
191 		pnfs_free_lseg_list(&free_me_list);
192 		put_layout_hdr(lo);
193 		iput(ino);
194 	}
195 	return rv;
196 }
197 
198 static u32 do_callback_layoutrecall(struct nfs_client *clp,
199 				    struct cb_layoutrecallargs *args)
200 {
201 	u32 res = NFS4ERR_DELAY;
202 
203 	dprintk("%s enter, type=%i\n", __func__, args->cbl_recall_type);
204 	if (test_and_set_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state))
205 		goto out;
206 	if (args->cbl_recall_type == RETURN_FILE)
207 		res = initiate_file_draining(clp, args);
208 	else
209 		res = initiate_bulk_draining(clp, args);
210 	clear_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state);
211 out:
212 	dprintk("%s returning %i\n", __func__, res);
213 	return res;
214 
215 }
216 
217 __be32 nfs4_callback_layoutrecall(struct cb_layoutrecallargs *args,
218 				  void *dummy, struct cb_process_state *cps)
219 {
220 	u32 res;
221 
222 	dprintk("%s: -->\n", __func__);
223 
224 	if (cps->clp)
225 		res = do_callback_layoutrecall(cps->clp, args);
226 	else
227 		res = NFS4ERR_OP_NOT_IN_SESSION;
228 
229 	dprintk("%s: exit with status = %d\n", __func__, res);
230 	return cpu_to_be32(res);
231 }
232 
233 static void pnfs_recall_all_layouts(struct nfs_client *clp)
234 {
235 	struct cb_layoutrecallargs args;
236 
237 	/* Pretend we got a CB_LAYOUTRECALL(ALL) */
238 	memset(&args, 0, sizeof(args));
239 	args.cbl_recall_type = RETURN_ALL;
240 	/* FIXME we ignore errors, what should we do? */
241 	do_callback_layoutrecall(clp, &args);
242 }
243 
244 __be32 nfs4_callback_devicenotify(struct cb_devicenotifyargs *args,
245 				  void *dummy, struct cb_process_state *cps)
246 {
247 	int i;
248 	__be32 res = 0;
249 	struct nfs_client *clp = cps->clp;
250 	struct nfs_server *server = NULL;
251 
252 	dprintk("%s: -->\n", __func__);
253 
254 	if (!clp) {
255 		res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
256 		goto out;
257 	}
258 
259 	for (i = 0; i < args->ndevs; i++) {
260 		struct cb_devicenotifyitem *dev = &args->devs[i];
261 
262 		if (!server ||
263 		    server->pnfs_curr_ld->id != dev->cbd_layout_type) {
264 			rcu_read_lock();
265 			list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
266 				if (server->pnfs_curr_ld &&
267 				    server->pnfs_curr_ld->id == dev->cbd_layout_type) {
268 					rcu_read_unlock();
269 					goto found;
270 				}
271 			rcu_read_unlock();
272 			dprintk("%s: layout type %u not found\n",
273 				__func__, dev->cbd_layout_type);
274 			continue;
275 		}
276 
277 	found:
278 		if (dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE)
279 			dprintk("%s: NOTIFY_DEVICEID4_CHANGE not supported, "
280 				"deleting instead\n", __func__);
281 		nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
282 	}
283 
284 out:
285 	kfree(args->devs);
286 	dprintk("%s: exit with status = %u\n",
287 		__func__, be32_to_cpu(res));
288 	return res;
289 }
290 
291 int nfs41_validate_delegation_stateid(struct nfs_delegation *delegation, const nfs4_stateid *stateid)
292 {
293 	if (delegation == NULL)
294 		return 0;
295 
296 	if (stateid->stateid.seqid != 0)
297 		return 0;
298 	if (memcmp(&delegation->stateid.stateid.other,
299 		   &stateid->stateid.other,
300 		   NFS4_STATEID_OTHER_SIZE))
301 		return 0;
302 
303 	return 1;
304 }
305 
306 /*
307  * Validate the sequenceID sent by the server.
308  * Return success if the sequenceID is one more than what we last saw on
309  * this slot, accounting for wraparound.  Increments the slot's sequence.
310  *
311  * We don't yet implement a duplicate request cache, instead we set the
312  * back channel ca_maxresponsesize_cached to zero. This is OK for now
313  * since we only currently implement idempotent callbacks anyway.
314  *
315  * We have a single slot backchannel at this time, so we don't bother
316  * checking the used_slots bit array on the table.  The lower layer guarantees
317  * a single outstanding callback request at a time.
318  */
319 static __be32
320 validate_seqid(struct nfs4_slot_table *tbl, struct cb_sequenceargs * args)
321 {
322 	struct nfs4_slot *slot;
323 
324 	dprintk("%s enter. slotid %d seqid %d\n",
325 		__func__, args->csa_slotid, args->csa_sequenceid);
326 
327 	if (args->csa_slotid > NFS41_BC_MAX_CALLBACKS)
328 		return htonl(NFS4ERR_BADSLOT);
329 
330 	slot = tbl->slots + args->csa_slotid;
331 	dprintk("%s slot table seqid: %d\n", __func__, slot->seq_nr);
332 
333 	/* Normal */
334 	if (likely(args->csa_sequenceid == slot->seq_nr + 1)) {
335 		slot->seq_nr++;
336 		return htonl(NFS4_OK);
337 	}
338 
339 	/* Replay */
340 	if (args->csa_sequenceid == slot->seq_nr) {
341 		dprintk("%s seqid %d is a replay\n",
342 			__func__, args->csa_sequenceid);
343 		/* Signal process_op to set this error on next op */
344 		if (args->csa_cachethis == 0)
345 			return htonl(NFS4ERR_RETRY_UNCACHED_REP);
346 
347 		/* The ca_maxresponsesize_cached is 0 with no DRC */
348 		else if (args->csa_cachethis == 1)
349 			return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
350 	}
351 
352 	/* Wraparound */
353 	if (args->csa_sequenceid == 1 && (slot->seq_nr + 1) == 0) {
354 		slot->seq_nr = 1;
355 		return htonl(NFS4_OK);
356 	}
357 
358 	/* Misordered request */
359 	return htonl(NFS4ERR_SEQ_MISORDERED);
360 }
361 
362 /*
363  * For each referring call triple, check the session's slot table for
364  * a match.  If the slot is in use and the sequence numbers match, the
365  * client is still waiting for a response to the original request.
366  */
367 static bool referring_call_exists(struct nfs_client *clp,
368 				  uint32_t nrclists,
369 				  struct referring_call_list *rclists)
370 {
371 	bool status = 0;
372 	int i, j;
373 	struct nfs4_session *session;
374 	struct nfs4_slot_table *tbl;
375 	struct referring_call_list *rclist;
376 	struct referring_call *ref;
377 
378 	/*
379 	 * XXX When client trunking is implemented, this becomes
380 	 * a session lookup from within the loop
381 	 */
382 	session = clp->cl_session;
383 	tbl = &session->fc_slot_table;
384 
385 	for (i = 0; i < nrclists; i++) {
386 		rclist = &rclists[i];
387 		if (memcmp(session->sess_id.data,
388 			   rclist->rcl_sessionid.data,
389 			   NFS4_MAX_SESSIONID_LEN) != 0)
390 			continue;
391 
392 		for (j = 0; j < rclist->rcl_nrefcalls; j++) {
393 			ref = &rclist->rcl_refcalls[j];
394 
395 			dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u "
396 				"slotid %u\n", __func__,
397 				((u32 *)&rclist->rcl_sessionid.data)[0],
398 				((u32 *)&rclist->rcl_sessionid.data)[1],
399 				((u32 *)&rclist->rcl_sessionid.data)[2],
400 				((u32 *)&rclist->rcl_sessionid.data)[3],
401 				ref->rc_sequenceid, ref->rc_slotid);
402 
403 			spin_lock(&tbl->slot_tbl_lock);
404 			status = (test_bit(ref->rc_slotid, tbl->used_slots) &&
405 				  tbl->slots[ref->rc_slotid].seq_nr ==
406 					ref->rc_sequenceid);
407 			spin_unlock(&tbl->slot_tbl_lock);
408 			if (status)
409 				goto out;
410 		}
411 	}
412 
413 out:
414 	return status;
415 }
416 
417 __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
418 			      struct cb_sequenceres *res,
419 			      struct cb_process_state *cps)
420 {
421 	struct nfs_client *clp;
422 	int i;
423 	__be32 status = htonl(NFS4ERR_BADSESSION);
424 
425 	cps->clp = NULL;
426 
427 	clp = nfs4_find_client_sessionid(args->csa_addr, &args->csa_sessionid);
428 	if (clp == NULL)
429 		goto out;
430 
431 	/* state manager is resetting the session */
432 	if (test_bit(NFS4_SESSION_DRAINING, &clp->cl_session->session_state)) {
433 		status = NFS4ERR_DELAY;
434 		goto out;
435 	}
436 
437 	status = validate_seqid(&clp->cl_session->bc_slot_table, args);
438 	if (status)
439 		goto out;
440 
441 	/*
442 	 * Check for pending referring calls.  If a match is found, a
443 	 * related callback was received before the response to the original
444 	 * call.
445 	 */
446 	if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
447 		status = htonl(NFS4ERR_DELAY);
448 		goto out;
449 	}
450 
451 	memcpy(&res->csr_sessionid, &args->csa_sessionid,
452 	       sizeof(res->csr_sessionid));
453 	res->csr_sequenceid = args->csa_sequenceid;
454 	res->csr_slotid = args->csa_slotid;
455 	res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
456 	res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
457 	nfs4_cb_take_slot(clp);
458 
459 out:
460 	cps->clp = clp; /* put in nfs4_callback_compound */
461 	for (i = 0; i < args->csa_nrclists; i++)
462 		kfree(args->csa_rclists[i].rcl_refcalls);
463 	kfree(args->csa_rclists);
464 
465 	if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
466 		cps->drc_status = status;
467 		status = 0;
468 	} else
469 		res->csr_status = status;
470 
471 	dprintk("%s: exit with status = %d res->csr_status %d\n", __func__,
472 		ntohl(status), ntohl(res->csr_status));
473 	return status;
474 }
475 
476 static bool
477 validate_bitmap_values(unsigned long mask)
478 {
479 	return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
480 }
481 
482 __be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy,
483 			       struct cb_process_state *cps)
484 {
485 	__be32 status;
486 	fmode_t flags = 0;
487 
488 	status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
489 	if (!cps->clp) /* set in cb_sequence */
490 		goto out;
491 
492 	dprintk("NFS: RECALL_ANY callback request from %s\n",
493 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
494 
495 	status = cpu_to_be32(NFS4ERR_INVAL);
496 	if (!validate_bitmap_values(args->craa_type_mask))
497 		goto out;
498 
499 	status = cpu_to_be32(NFS4_OK);
500 	if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *)
501 		     &args->craa_type_mask))
502 		flags = FMODE_READ;
503 	if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *)
504 		     &args->craa_type_mask))
505 		flags |= FMODE_WRITE;
506 	if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *)
507 		     &args->craa_type_mask))
508 		pnfs_recall_all_layouts(cps->clp);
509 	if (flags)
510 		nfs_expire_all_delegation_types(cps->clp, flags);
511 out:
512 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
513 	return status;
514 }
515 
516 /* Reduce the fore channel's max_slots to the target value */
517 __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy,
518 				struct cb_process_state *cps)
519 {
520 	struct nfs4_slot_table *fc_tbl;
521 	__be32 status;
522 
523 	status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
524 	if (!cps->clp) /* set in cb_sequence */
525 		goto out;
526 
527 	dprintk("NFS: CB_RECALL_SLOT request from %s target max slots %d\n",
528 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
529 		args->crsa_target_max_slots);
530 
531 	fc_tbl = &cps->clp->cl_session->fc_slot_table;
532 
533 	status = htonl(NFS4ERR_BAD_HIGH_SLOT);
534 	if (args->crsa_target_max_slots > fc_tbl->max_slots ||
535 	    args->crsa_target_max_slots < 1)
536 		goto out;
537 
538 	status = htonl(NFS4_OK);
539 	if (args->crsa_target_max_slots == fc_tbl->max_slots)
540 		goto out;
541 
542 	fc_tbl->target_max_slots = args->crsa_target_max_slots;
543 	nfs41_handle_recall_slot(cps->clp);
544 out:
545 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
546 	return status;
547 }
548 #endif /* CONFIG_NFS_V4_1 */
549