xref: /openbmc/linux/fs/nfs/pnfs.h (revision a67ff6a54095e27093ea501fb143fefe51a536c2)
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 void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg);
182 int pnfs_layout_process(struct nfs4_layoutget *lgp);
183 void pnfs_free_lseg_list(struct list_head *tmp_list);
184 void pnfs_destroy_layout(struct nfs_inode *);
185 void pnfs_destroy_all_layouts(struct nfs_client *);
186 void put_layout_hdr(struct pnfs_layout_hdr *lo);
187 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
188 			     const nfs4_stateid *new,
189 			     bool update_barrier);
190 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
191 				  struct pnfs_layout_hdr *lo,
192 				  struct nfs4_state *open_state);
193 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
194 				struct list_head *tmp_list,
195 				struct pnfs_layout_range *recall_range);
196 bool pnfs_roc(struct inode *ino);
197 void pnfs_roc_release(struct inode *ino);
198 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
199 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
200 void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
201 void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data);
202 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
203 int _pnfs_return_layout(struct inode *);
204 void pnfs_ld_write_done(struct nfs_write_data *);
205 void pnfs_ld_read_done(struct nfs_read_data *);
206 struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,
207 					       struct nfs_open_context *ctx,
208 					       loff_t pos,
209 					       u64 count,
210 					       enum pnfs_iomode iomode,
211 					       gfp_t gfp_flags);
212 
213 void nfs4_deviceid_mark_client_invalid(struct nfs_client *clp);
214 
215 /* nfs4_deviceid_flags */
216 enum {
217 	NFS_DEVICEID_INVALID = 0,       /* set when MDS clientid recalled */
218 };
219 
220 /* pnfs_dev.c */
221 struct nfs4_deviceid_node {
222 	struct hlist_node		node;
223 	struct hlist_node		tmpnode;
224 	const struct pnfs_layoutdriver_type *ld;
225 	const struct nfs_client		*nfs_client;
226 	unsigned long 			flags;
227 	struct nfs4_deviceid		deviceid;
228 	atomic_t			ref;
229 };
230 
231 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
232 struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
233 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
234 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
235 			     const struct pnfs_layoutdriver_type *,
236 			     const struct nfs_client *,
237 			     const struct nfs4_deviceid *);
238 struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
239 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
240 void nfs4_deviceid_purge_client(const struct nfs_client *);
241 
242 static inline int lo_fail_bit(u32 iomode)
243 {
244 	return iomode == IOMODE_RW ?
245 			 NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
246 }
247 
248 static inline struct pnfs_layout_segment *
249 get_lseg(struct pnfs_layout_segment *lseg)
250 {
251 	if (lseg) {
252 		atomic_inc(&lseg->pls_refcount);
253 		smp_mb__after_atomic_inc();
254 	}
255 	return lseg;
256 }
257 
258 /* Return true if a layout driver is being used for this mountpoint */
259 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
260 {
261 	return nfss->pnfs_curr_ld != NULL;
262 }
263 
264 static inline void
265 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
266 {
267 	if (lseg) {
268 		struct pnfs_layoutdriver_type *ld;
269 
270 		ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
271 		if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
272 			set_bit(PG_PNFS_COMMIT, &req->wb_flags);
273 			req->wb_commit_lseg = get_lseg(lseg);
274 		}
275 	}
276 }
277 
278 static inline int
279 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
280 {
281 	if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
282 		return PNFS_NOT_ATTEMPTED;
283 	return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
284 }
285 
286 static inline struct list_head *
287 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
288 {
289 	struct list_head *rv;
290 
291 	if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
292 		struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
293 
294 		set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
295 		rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
296 		/* matched by ref taken when PG_PNFS_COMMIT is set */
297 		put_lseg(req->wb_commit_lseg);
298 	} else
299 		rv = mds;
300 	return rv;
301 }
302 
303 static inline void pnfs_clear_request_commit(struct nfs_page *req)
304 {
305 	if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
306 		put_lseg(req->wb_commit_lseg);
307 }
308 
309 /* Should the pNFS client commit and return the layout upon a setattr */
310 static inline bool
311 pnfs_ld_layoutret_on_setattr(struct inode *inode)
312 {
313 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
314 		return false;
315 	return NFS_SERVER(inode)->pnfs_curr_ld->flags &
316 		PNFS_LAYOUTRET_ON_SETATTR;
317 }
318 
319 static inline int pnfs_return_layout(struct inode *ino)
320 {
321 	struct nfs_inode *nfsi = NFS_I(ino);
322 	struct nfs_server *nfss = NFS_SERVER(ino);
323 
324 	if (pnfs_enabled_sb(nfss) && nfsi->layout)
325 		return _pnfs_return_layout(ino);
326 
327 	return 0;
328 }
329 
330 #else  /* CONFIG_NFS_V4_1 */
331 
332 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
333 {
334 }
335 
336 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
337 {
338 }
339 
340 static inline struct pnfs_layout_segment *
341 get_lseg(struct pnfs_layout_segment *lseg)
342 {
343 	return NULL;
344 }
345 
346 static inline void put_lseg(struct pnfs_layout_segment *lseg)
347 {
348 }
349 
350 static inline int pnfs_return_layout(struct inode *ino)
351 {
352 	return 0;
353 }
354 
355 static inline bool
356 pnfs_ld_layoutret_on_setattr(struct inode *inode)
357 {
358 	return false;
359 }
360 
361 static inline bool
362 pnfs_roc(struct inode *ino)
363 {
364 	return false;
365 }
366 
367 static inline void
368 pnfs_roc_release(struct inode *ino)
369 {
370 }
371 
372 static inline void
373 pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
374 {
375 }
376 
377 static inline bool
378 pnfs_roc_drain(struct inode *ino, u32 *barrier)
379 {
380 	return false;
381 }
382 
383 static inline void set_pnfs_layoutdriver(struct nfs_server *s,
384 					 const struct nfs_fh *mntfh, u32 id)
385 {
386 }
387 
388 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
389 {
390 }
391 
392 static inline bool pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode)
393 {
394 	return false;
395 }
396 
397 static inline bool pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags)
398 {
399 	return false;
400 }
401 
402 static inline void
403 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
404 {
405 }
406 
407 static inline int
408 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
409 {
410 	return PNFS_NOT_ATTEMPTED;
411 }
412 
413 static inline struct list_head *
414 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
415 {
416 	return mds;
417 }
418 
419 static inline void pnfs_clear_request_commit(struct nfs_page *req)
420 {
421 }
422 
423 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
424 {
425 	return 0;
426 }
427 
428 static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
429 {
430 }
431 #endif /* CONFIG_NFS_V4_1 */
432 
433 #endif /* FS_NFS_PNFS_H */
434