xref: /linux/fs/nfs/pnfs.h (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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 };
72 
73 struct nfs4_deviceid_node;
74 
75 /* Per-layout driver specific registration structure */
76 struct pnfs_layoutdriver_type {
77 	struct list_head pnfs_tblid;
78 	const u32 id;
79 	const char *name;
80 	struct module *owner;
81 	unsigned flags;
82 
83 	int (*set_layoutdriver) (struct nfs_server *, const struct nfs_fh *);
84 	int (*clear_layoutdriver) (struct nfs_server *);
85 
86 	struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
87 	void (*free_layout_hdr) (struct pnfs_layout_hdr *);
88 
89 	struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
90 	void (*free_lseg) (struct pnfs_layout_segment *lseg);
91 
92 	/* test for nfs page cache coalescing */
93 	const struct nfs_pageio_ops *pg_read_ops;
94 	const struct nfs_pageio_ops *pg_write_ops;
95 
96 	/* Returns true if layoutdriver wants to divert this request to
97 	 * driver's commit routine.
98 	 */
99 	bool (*mark_pnfs_commit)(struct pnfs_layout_segment *lseg);
100 	struct list_head * (*choose_commit_list) (struct nfs_page *req);
101 	int (*commit_pagelist)(struct inode *inode, struct list_head *mds_pages, int how);
102 
103 	/*
104 	 * Return PNFS_ATTEMPTED to indicate the layout code has attempted
105 	 * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
106 	 */
107 	enum pnfs_try_status (*read_pagelist) (struct nfs_read_data *nfs_data);
108 	enum pnfs_try_status (*write_pagelist) (struct nfs_write_data *nfs_data, int how);
109 
110 	void (*free_deviceid_node) (struct nfs4_deviceid_node *);
111 
112 	void (*encode_layoutreturn) (struct pnfs_layout_hdr *layoutid,
113 				     struct xdr_stream *xdr,
114 				     const struct nfs4_layoutreturn_args *args);
115 
116 	void (*cleanup_layoutcommit) (struct nfs4_layoutcommit_data *data);
117 
118 	void (*encode_layoutcommit) (struct pnfs_layout_hdr *layoutid,
119 				     struct xdr_stream *xdr,
120 				     const struct nfs4_layoutcommit_args *args);
121 };
122 
123 struct pnfs_layout_hdr {
124 	atomic_t		plh_refcount;
125 	struct list_head	plh_layouts;   /* other client layouts */
126 	struct list_head	plh_bulk_recall; /* clnt list of bulk recalls */
127 	struct list_head	plh_segs;      /* layout segments list */
128 	nfs4_stateid		plh_stateid;
129 	atomic_t		plh_outstanding; /* number of RPCs out */
130 	unsigned long		plh_block_lgets; /* block LAYOUTGET if >0 */
131 	u32			plh_barrier; /* ignore lower seqids */
132 	unsigned long		plh_flags;
133 	loff_t			plh_lwb; /* last write byte for layoutcommit */
134 	struct rpc_cred		*plh_lc_cred; /* layoutcommit cred */
135 	struct inode		*plh_inode;
136 };
137 
138 struct pnfs_device {
139 	struct nfs4_deviceid dev_id;
140 	unsigned int  layout_type;
141 	unsigned int  mincount;
142 	struct page **pages;
143 	unsigned int  pgbase;
144 	unsigned int  pglen;
145 };
146 
147 #define NFS4_PNFS_GETDEVLIST_MAXNUM 16
148 
149 struct pnfs_devicelist {
150 	unsigned int		eof;
151 	unsigned int		num_devs;
152 	struct nfs4_deviceid	dev_id[NFS4_PNFS_GETDEVLIST_MAXNUM];
153 };
154 
155 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
156 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
157 
158 /* nfs4proc.c */
159 extern int nfs4_proc_getdevicelist(struct nfs_server *server,
160 				   const struct nfs_fh *fh,
161 				   struct pnfs_devicelist *devlist);
162 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
163 				   struct pnfs_device *dev);
164 extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
165 extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp);
166 
167 /* pnfs.c */
168 void get_layout_hdr(struct pnfs_layout_hdr *lo);
169 void put_lseg(struct pnfs_layout_segment *lseg);
170 
171 bool pnfs_pageio_init_read(struct nfs_pageio_descriptor *, struct inode *);
172 bool pnfs_pageio_init_write(struct nfs_pageio_descriptor *, struct inode *, int);
173 
174 void set_pnfs_layoutdriver(struct nfs_server *, const struct nfs_fh *, u32);
175 void unset_pnfs_layoutdriver(struct nfs_server *);
176 void pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *, struct nfs_page *);
177 int pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc);
178 void pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *, struct nfs_page *);
179 int pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc);
180 bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req);
181 int pnfs_layout_process(struct nfs4_layoutget *lgp);
182 void pnfs_free_lseg_list(struct list_head *tmp_list);
183 void pnfs_destroy_layout(struct nfs_inode *);
184 void pnfs_destroy_all_layouts(struct nfs_client *);
185 void put_layout_hdr(struct pnfs_layout_hdr *lo);
186 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
187 			     const nfs4_stateid *new,
188 			     bool update_barrier);
189 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
190 				  struct pnfs_layout_hdr *lo,
191 				  struct nfs4_state *open_state);
192 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
193 				struct list_head *tmp_list,
194 				struct pnfs_layout_range *recall_range);
195 bool pnfs_roc(struct inode *ino);
196 void pnfs_roc_release(struct inode *ino);
197 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
198 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
199 void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
200 void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data);
201 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
202 int _pnfs_return_layout(struct inode *);
203 int pnfs_ld_write_done(struct nfs_write_data *);
204 int pnfs_ld_read_done(struct nfs_read_data *);
205 struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,
206 					       struct nfs_open_context *ctx,
207 					       loff_t pos,
208 					       u64 count,
209 					       enum pnfs_iomode iomode,
210 					       gfp_t gfp_flags);
211 
212 void nfs4_deviceid_mark_client_invalid(struct nfs_client *clp);
213 
214 /* nfs4_deviceid_flags */
215 enum {
216 	NFS_DEVICEID_INVALID = 0,       /* set when MDS clientid recalled */
217 };
218 
219 /* pnfs_dev.c */
220 struct nfs4_deviceid_node {
221 	struct hlist_node		node;
222 	struct hlist_node		tmpnode;
223 	const struct pnfs_layoutdriver_type *ld;
224 	const struct nfs_client		*nfs_client;
225 	unsigned long 			flags;
226 	struct nfs4_deviceid		deviceid;
227 	atomic_t			ref;
228 };
229 
230 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
231 struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
232 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
233 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
234 			     const struct pnfs_layoutdriver_type *,
235 			     const struct nfs_client *,
236 			     const struct nfs4_deviceid *);
237 struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
238 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
239 void nfs4_deviceid_purge_client(const struct nfs_client *);
240 
241 static inline int lo_fail_bit(u32 iomode)
242 {
243 	return iomode == IOMODE_RW ?
244 			 NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
245 }
246 
247 static inline struct pnfs_layout_segment *
248 get_lseg(struct pnfs_layout_segment *lseg)
249 {
250 	if (lseg) {
251 		atomic_inc(&lseg->pls_refcount);
252 		smp_mb__after_atomic_inc();
253 	}
254 	return lseg;
255 }
256 
257 /* Return true if a layout driver is being used for this mountpoint */
258 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
259 {
260 	return nfss->pnfs_curr_ld != NULL;
261 }
262 
263 static inline void
264 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
265 {
266 	if (lseg) {
267 		struct pnfs_layoutdriver_type *ld;
268 
269 		ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
270 		if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
271 			set_bit(PG_PNFS_COMMIT, &req->wb_flags);
272 			req->wb_commit_lseg = get_lseg(lseg);
273 		}
274 	}
275 }
276 
277 static inline int
278 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
279 {
280 	if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
281 		return PNFS_NOT_ATTEMPTED;
282 	return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
283 }
284 
285 static inline struct list_head *
286 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
287 {
288 	struct list_head *rv;
289 
290 	if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
291 		struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
292 
293 		set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
294 		rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
295 		/* matched by ref taken when PG_PNFS_COMMIT is set */
296 		put_lseg(req->wb_commit_lseg);
297 	} else
298 		rv = mds;
299 	return rv;
300 }
301 
302 static inline void pnfs_clear_request_commit(struct nfs_page *req)
303 {
304 	if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
305 		put_lseg(req->wb_commit_lseg);
306 }
307 
308 /* Should the pNFS client commit and return the layout upon a setattr */
309 static inline bool
310 pnfs_ld_layoutret_on_setattr(struct inode *inode)
311 {
312 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
313 		return false;
314 	return NFS_SERVER(inode)->pnfs_curr_ld->flags &
315 		PNFS_LAYOUTRET_ON_SETATTR;
316 }
317 
318 static inline int pnfs_return_layout(struct inode *ino)
319 {
320 	struct nfs_inode *nfsi = NFS_I(ino);
321 	struct nfs_server *nfss = NFS_SERVER(ino);
322 
323 	if (pnfs_enabled_sb(nfss) && nfsi->layout)
324 		return _pnfs_return_layout(ino);
325 
326 	return 0;
327 }
328 
329 #else  /* CONFIG_NFS_V4_1 */
330 
331 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
332 {
333 }
334 
335 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
336 {
337 }
338 
339 static inline struct pnfs_layout_segment *
340 get_lseg(struct pnfs_layout_segment *lseg)
341 {
342 	return NULL;
343 }
344 
345 static inline void put_lseg(struct pnfs_layout_segment *lseg)
346 {
347 }
348 
349 static inline int pnfs_return_layout(struct inode *ino)
350 {
351 	return 0;
352 }
353 
354 static inline bool
355 pnfs_ld_layoutret_on_setattr(struct inode *inode)
356 {
357 	return false;
358 }
359 
360 static inline bool
361 pnfs_roc(struct inode *ino)
362 {
363 	return false;
364 }
365 
366 static inline void
367 pnfs_roc_release(struct inode *ino)
368 {
369 }
370 
371 static inline void
372 pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
373 {
374 }
375 
376 static inline bool
377 pnfs_roc_drain(struct inode *ino, u32 *barrier)
378 {
379 	return false;
380 }
381 
382 static inline void set_pnfs_layoutdriver(struct nfs_server *s,
383 					 const struct nfs_fh *mntfh, u32 id)
384 {
385 }
386 
387 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
388 {
389 }
390 
391 static inline bool pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode)
392 {
393 	return false;
394 }
395 
396 static inline bool pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags)
397 {
398 	return false;
399 }
400 
401 static inline void
402 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
403 {
404 }
405 
406 static inline int
407 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
408 {
409 	return PNFS_NOT_ATTEMPTED;
410 }
411 
412 static inline struct list_head *
413 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
414 {
415 	return mds;
416 }
417 
418 static inline void pnfs_clear_request_commit(struct nfs_page *req)
419 {
420 }
421 
422 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
423 {
424 	return 0;
425 }
426 
427 static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
428 {
429 }
430 #endif /* CONFIG_NFS_V4_1 */
431 
432 #endif /* FS_NFS_PNFS_H */
433