xref: /linux/fs/nfs/pnfs.h (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  *  pNFS client data structures.
3  *
4  *  Copyright (c) 2002
5  *  The Regents of the University of Michigan
6  *  All Rights Reserved
7  *
8  *  Dean Hildebrand <dhildebz@umich.edu>
9  *
10  *  Permission is granted to use, copy, create derivative works, and
11  *  redistribute this software and such derivative works for any purpose,
12  *  so long as the name of the University of Michigan is not used in
13  *  any advertising or publicity pertaining to the use or distribution
14  *  of this software without specific, written prior authorization. If
15  *  the above copyright notice or any other identification of the
16  *  University of Michigan is included in any copy of any portion of
17  *  this software, then the disclaimer below must also be included.
18  *
19  *  This software is provided as is, without representation or warranty
20  *  of any kind either express or implied, including without limitation
21  *  the implied warranties of merchantability, fitness for a particular
22  *  purpose, or noninfringement.  The Regents of the University of
23  *  Michigan shall not be liable for any damages, including special,
24  *  indirect, incidental, or consequential damages, with respect to any
25  *  claim arising out of or in connection with the use of the software,
26  *  even if it has been or is hereafter advised of the possibility of
27  *  such damages.
28  */
29 
30 #ifndef FS_NFS_PNFS_H
31 #define FS_NFS_PNFS_H
32 
33 #include <linux/nfs_fs.h>
34 #include <linux/nfs_page.h>
35 
36 enum {
37 	NFS_LSEG_VALID = 0,	/* cleared when lseg is recalled/returned */
38 	NFS_LSEG_ROC,		/* roc bit received from server */
39 	NFS_LSEG_LAYOUTCOMMIT,	/* layoutcommit bit set for layoutcommit */
40 };
41 
42 struct pnfs_layout_segment {
43 	struct list_head pls_list;
44 	struct list_head pls_lc_list;
45 	struct pnfs_layout_range pls_range;
46 	atomic_t pls_refcount;
47 	unsigned long pls_flags;
48 	struct pnfs_layout_hdr *pls_layout;
49 };
50 
51 enum pnfs_try_status {
52 	PNFS_ATTEMPTED     = 0,
53 	PNFS_NOT_ATTEMPTED = 1,
54 };
55 
56 #ifdef CONFIG_NFS_V4_1
57 
58 #define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"
59 
60 enum {
61 	NFS_LAYOUT_RO_FAILED = 0,	/* get ro layout failed stop trying */
62 	NFS_LAYOUT_RW_FAILED,		/* get rw layout failed stop trying */
63 	NFS_LAYOUT_BULK_RECALL,		/* bulk recall affecting layout */
64 	NFS_LAYOUT_ROC,			/* some lseg had roc bit set */
65 	NFS_LAYOUT_DESTROYED,		/* no new use of layout allowed */
66 };
67 
68 enum layoutdriver_policy_flags {
69 	/* Should the pNFS client commit and return the layout upon a setattr */
70 	PNFS_LAYOUTRET_ON_SETATTR	= 1 << 0,
71 	PNFS_LAYOUTRET_ON_ERROR		= 1 << 1,
72 };
73 
74 struct nfs4_deviceid_node;
75 
76 /* Per-layout driver specific registration structure */
77 struct pnfs_layoutdriver_type {
78 	struct list_head pnfs_tblid;
79 	const u32 id;
80 	const char *name;
81 	struct module *owner;
82 	unsigned flags;
83 
84 	int (*set_layoutdriver) (struct nfs_server *, const struct nfs_fh *);
85 	int (*clear_layoutdriver) (struct nfs_server *);
86 
87 	struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
88 	void (*free_layout_hdr) (struct pnfs_layout_hdr *);
89 
90 	struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
91 	void (*free_lseg) (struct pnfs_layout_segment *lseg);
92 
93 	/* test for nfs page cache coalescing */
94 	const struct nfs_pageio_ops *pg_read_ops;
95 	const struct nfs_pageio_ops *pg_write_ops;
96 
97 	/* Returns true if layoutdriver wants to divert this request to
98 	 * driver's commit routine.
99 	 */
100 	bool (*mark_pnfs_commit)(struct pnfs_layout_segment *lseg);
101 	struct list_head * (*choose_commit_list) (struct nfs_page *req);
102 	int (*commit_pagelist)(struct inode *inode, struct list_head *mds_pages, int how);
103 
104 	/*
105 	 * Return PNFS_ATTEMPTED to indicate the layout code has attempted
106 	 * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
107 	 */
108 	enum pnfs_try_status (*read_pagelist) (struct nfs_read_data *nfs_data);
109 	enum pnfs_try_status (*write_pagelist) (struct nfs_write_data *nfs_data, int how);
110 
111 	void (*free_deviceid_node) (struct nfs4_deviceid_node *);
112 
113 	void (*encode_layoutreturn) (struct pnfs_layout_hdr *layoutid,
114 				     struct xdr_stream *xdr,
115 				     const struct nfs4_layoutreturn_args *args);
116 
117 	void (*cleanup_layoutcommit) (struct nfs4_layoutcommit_data *data);
118 
119 	void (*encode_layoutcommit) (struct pnfs_layout_hdr *layoutid,
120 				     struct xdr_stream *xdr,
121 				     const struct nfs4_layoutcommit_args *args);
122 };
123 
124 struct pnfs_layout_hdr {
125 	atomic_t		plh_refcount;
126 	struct list_head	plh_layouts;   /* other client layouts */
127 	struct list_head	plh_bulk_recall; /* clnt list of bulk recalls */
128 	struct list_head	plh_segs;      /* layout segments list */
129 	nfs4_stateid		plh_stateid;
130 	atomic_t		plh_outstanding; /* number of RPCs out */
131 	unsigned long		plh_block_lgets; /* block LAYOUTGET if >0 */
132 	u32			plh_barrier; /* ignore lower seqids */
133 	unsigned long		plh_flags;
134 	loff_t			plh_lwb; /* last write byte for layoutcommit */
135 	struct rpc_cred		*plh_lc_cred; /* layoutcommit cred */
136 	struct inode		*plh_inode;
137 };
138 
139 struct pnfs_device {
140 	struct nfs4_deviceid dev_id;
141 	unsigned int  layout_type;
142 	unsigned int  mincount;
143 	struct page **pages;
144 	unsigned int  pgbase;
145 	unsigned int  pglen;
146 };
147 
148 #define NFS4_PNFS_GETDEVLIST_MAXNUM 16
149 
150 struct pnfs_devicelist {
151 	unsigned int		eof;
152 	unsigned int		num_devs;
153 	struct nfs4_deviceid	dev_id[NFS4_PNFS_GETDEVLIST_MAXNUM];
154 };
155 
156 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
157 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
158 
159 /* nfs4proc.c */
160 extern int nfs4_proc_getdevicelist(struct nfs_server *server,
161 				   const struct nfs_fh *fh,
162 				   struct pnfs_devicelist *devlist);
163 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
164 				   struct pnfs_device *dev);
165 extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
166 extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp);
167 
168 /* pnfs.c */
169 void get_layout_hdr(struct pnfs_layout_hdr *lo);
170 void put_lseg(struct pnfs_layout_segment *lseg);
171 
172 bool pnfs_pageio_init_read(struct nfs_pageio_descriptor *, struct inode *);
173 bool pnfs_pageio_init_write(struct nfs_pageio_descriptor *, struct inode *, int);
174 
175 void set_pnfs_layoutdriver(struct nfs_server *, const struct nfs_fh *, u32);
176 void unset_pnfs_layoutdriver(struct nfs_server *);
177 void pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *, struct nfs_page *);
178 int pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc);
179 void pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *, struct nfs_page *);
180 int pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc);
181 bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req);
182 void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg);
183 int pnfs_layout_process(struct nfs4_layoutget *lgp);
184 void pnfs_free_lseg_list(struct list_head *tmp_list);
185 void pnfs_destroy_layout(struct nfs_inode *);
186 void pnfs_destroy_all_layouts(struct nfs_client *);
187 void put_layout_hdr(struct pnfs_layout_hdr *lo);
188 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
189 			     const nfs4_stateid *new,
190 			     bool update_barrier);
191 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
192 				  struct pnfs_layout_hdr *lo,
193 				  struct nfs4_state *open_state);
194 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
195 				struct list_head *tmp_list,
196 				struct pnfs_layout_range *recall_range);
197 bool pnfs_roc(struct inode *ino);
198 void pnfs_roc_release(struct inode *ino);
199 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
200 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
201 void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
202 void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data);
203 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
204 int _pnfs_return_layout(struct inode *);
205 void pnfs_ld_write_done(struct nfs_write_data *);
206 void pnfs_ld_read_done(struct nfs_read_data *);
207 struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,
208 					       struct nfs_open_context *ctx,
209 					       loff_t pos,
210 					       u64 count,
211 					       enum pnfs_iomode iomode,
212 					       gfp_t gfp_flags);
213 
214 void nfs4_deviceid_mark_client_invalid(struct nfs_client *clp);
215 
216 /* nfs4_deviceid_flags */
217 enum {
218 	NFS_DEVICEID_INVALID = 0,       /* set when MDS clientid recalled */
219 };
220 
221 /* pnfs_dev.c */
222 struct nfs4_deviceid_node {
223 	struct hlist_node		node;
224 	struct hlist_node		tmpnode;
225 	const struct pnfs_layoutdriver_type *ld;
226 	const struct nfs_client		*nfs_client;
227 	unsigned long 			flags;
228 	struct nfs4_deviceid		deviceid;
229 	atomic_t			ref;
230 };
231 
232 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
233 struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
234 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
235 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
236 			     const struct pnfs_layoutdriver_type *,
237 			     const struct nfs_client *,
238 			     const struct nfs4_deviceid *);
239 struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
240 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
241 void nfs4_deviceid_purge_client(const struct nfs_client *);
242 
243 static inline int lo_fail_bit(u32 iomode)
244 {
245 	return iomode == IOMODE_RW ?
246 			 NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
247 }
248 
249 static inline struct pnfs_layout_segment *
250 get_lseg(struct pnfs_layout_segment *lseg)
251 {
252 	if (lseg) {
253 		atomic_inc(&lseg->pls_refcount);
254 		smp_mb__after_atomic_inc();
255 	}
256 	return lseg;
257 }
258 
259 /* Return true if a layout driver is being used for this mountpoint */
260 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
261 {
262 	return nfss->pnfs_curr_ld != NULL;
263 }
264 
265 static inline void
266 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
267 {
268 	if (lseg) {
269 		struct pnfs_layoutdriver_type *ld;
270 
271 		ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
272 		if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
273 			set_bit(PG_PNFS_COMMIT, &req->wb_flags);
274 			req->wb_commit_lseg = get_lseg(lseg);
275 		}
276 	}
277 }
278 
279 static inline int
280 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
281 {
282 	if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
283 		return PNFS_NOT_ATTEMPTED;
284 	return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
285 }
286 
287 static inline struct list_head *
288 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
289 {
290 	struct list_head *rv;
291 
292 	if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
293 		struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
294 
295 		set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
296 		rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
297 		/* matched by ref taken when PG_PNFS_COMMIT is set */
298 		put_lseg(req->wb_commit_lseg);
299 	} else
300 		rv = mds;
301 	return rv;
302 }
303 
304 static inline void pnfs_clear_request_commit(struct nfs_page *req)
305 {
306 	if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
307 		put_lseg(req->wb_commit_lseg);
308 }
309 
310 /* Should the pNFS client commit and return the layout upon a setattr */
311 static inline bool
312 pnfs_ld_layoutret_on_setattr(struct inode *inode)
313 {
314 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
315 		return false;
316 	return NFS_SERVER(inode)->pnfs_curr_ld->flags &
317 		PNFS_LAYOUTRET_ON_SETATTR;
318 }
319 
320 static inline int pnfs_return_layout(struct inode *ino)
321 {
322 	struct nfs_inode *nfsi = NFS_I(ino);
323 	struct nfs_server *nfss = NFS_SERVER(ino);
324 
325 	if (pnfs_enabled_sb(nfss) && nfsi->layout)
326 		return _pnfs_return_layout(ino);
327 
328 	return 0;
329 }
330 
331 #else  /* CONFIG_NFS_V4_1 */
332 
333 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
334 {
335 }
336 
337 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
338 {
339 }
340 
341 static inline struct pnfs_layout_segment *
342 get_lseg(struct pnfs_layout_segment *lseg)
343 {
344 	return NULL;
345 }
346 
347 static inline void put_lseg(struct pnfs_layout_segment *lseg)
348 {
349 }
350 
351 static inline int pnfs_return_layout(struct inode *ino)
352 {
353 	return 0;
354 }
355 
356 static inline bool
357 pnfs_ld_layoutret_on_setattr(struct inode *inode)
358 {
359 	return false;
360 }
361 
362 static inline bool
363 pnfs_roc(struct inode *ino)
364 {
365 	return false;
366 }
367 
368 static inline void
369 pnfs_roc_release(struct inode *ino)
370 {
371 }
372 
373 static inline void
374 pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
375 {
376 }
377 
378 static inline bool
379 pnfs_roc_drain(struct inode *ino, u32 *barrier)
380 {
381 	return false;
382 }
383 
384 static inline void set_pnfs_layoutdriver(struct nfs_server *s,
385 					 const struct nfs_fh *mntfh, u32 id)
386 {
387 }
388 
389 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
390 {
391 }
392 
393 static inline bool pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode)
394 {
395 	return false;
396 }
397 
398 static inline bool pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags)
399 {
400 	return false;
401 }
402 
403 static inline void
404 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
405 {
406 }
407 
408 static inline int
409 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
410 {
411 	return PNFS_NOT_ATTEMPTED;
412 }
413 
414 static inline struct list_head *
415 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
416 {
417 	return mds;
418 }
419 
420 static inline void pnfs_clear_request_commit(struct nfs_page *req)
421 {
422 }
423 
424 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
425 {
426 	return 0;
427 }
428 
429 static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
430 {
431 }
432 #endif /* CONFIG_NFS_V4_1 */
433 
434 #endif /* FS_NFS_PNFS_H */
435