xref: /openbmc/linux/fs/nfs/pnfs.h (revision 7fe2f639)
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 };
40 
41 struct pnfs_layout_segment {
42 	struct list_head pls_list;
43 	struct pnfs_layout_range pls_range;
44 	atomic_t pls_refcount;
45 	unsigned long pls_flags;
46 	struct pnfs_layout_hdr *pls_layout;
47 	struct rpc_cred	*pls_lc_cred; /* LAYOUTCOMMIT credential */
48 	loff_t pls_end_pos; /* LAYOUTCOMMIT write end */
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 	struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
84 	void (*free_layout_hdr) (struct pnfs_layout_hdr *);
85 
86 	struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
87 	void (*free_lseg) (struct pnfs_layout_segment *lseg);
88 
89 	/* test for nfs page cache coalescing */
90 	bool (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *);
91 
92 	/* Returns true if layoutdriver wants to divert this request to
93 	 * driver's commit routine.
94 	 */
95 	bool (*mark_pnfs_commit)(struct pnfs_layout_segment *lseg);
96 	struct list_head * (*choose_commit_list) (struct nfs_page *req);
97 	int (*commit_pagelist)(struct inode *inode, struct list_head *mds_pages, int how);
98 
99 	/*
100 	 * Return PNFS_ATTEMPTED to indicate the layout code has attempted
101 	 * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
102 	 */
103 	enum pnfs_try_status (*read_pagelist) (struct nfs_read_data *nfs_data);
104 	enum pnfs_try_status (*write_pagelist) (struct nfs_write_data *nfs_data, int how);
105 
106 	void (*free_deviceid_node) (struct nfs4_deviceid_node *);
107 
108 	void (*encode_layoutreturn) (struct pnfs_layout_hdr *layoutid,
109 				     struct xdr_stream *xdr,
110 				     const struct nfs4_layoutreturn_args *args);
111 
112 	void (*encode_layoutcommit) (struct pnfs_layout_hdr *layoutid,
113 				     struct xdr_stream *xdr,
114 				     const struct nfs4_layoutcommit_args *args);
115 };
116 
117 struct pnfs_layout_hdr {
118 	atomic_t		plh_refcount;
119 	struct list_head	plh_layouts;   /* other client layouts */
120 	struct list_head	plh_bulk_recall; /* clnt list of bulk recalls */
121 	struct list_head	plh_segs;      /* layout segments list */
122 	nfs4_stateid		plh_stateid;
123 	atomic_t		plh_outstanding; /* number of RPCs out */
124 	unsigned long		plh_block_lgets; /* block LAYOUTGET if >0 */
125 	u32			plh_barrier; /* ignore lower seqids */
126 	unsigned long		plh_flags;
127 	struct inode		*plh_inode;
128 };
129 
130 struct pnfs_device {
131 	struct nfs4_deviceid dev_id;
132 	unsigned int  layout_type;
133 	unsigned int  mincount;
134 	struct page **pages;
135 	unsigned int  pgbase;
136 	unsigned int  pglen;
137 };
138 
139 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
140 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
141 
142 /* nfs4proc.c */
143 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
144 				   struct pnfs_device *dev);
145 extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
146 extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp);
147 
148 /* pnfs.c */
149 void get_layout_hdr(struct pnfs_layout_hdr *lo);
150 void put_lseg(struct pnfs_layout_segment *lseg);
151 struct pnfs_layout_segment *
152 pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
153 		   loff_t pos, u64 count, enum pnfs_iomode access_type,
154 		   gfp_t gfp_flags);
155 void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
156 void unset_pnfs_layoutdriver(struct nfs_server *);
157 enum pnfs_try_status pnfs_try_to_write_data(struct nfs_write_data *,
158 					     const struct rpc_call_ops *, int);
159 enum pnfs_try_status pnfs_try_to_read_data(struct nfs_read_data *,
160 					    const struct rpc_call_ops *);
161 bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req);
162 int pnfs_layout_process(struct nfs4_layoutget *lgp);
163 void pnfs_free_lseg_list(struct list_head *tmp_list);
164 void pnfs_destroy_layout(struct nfs_inode *);
165 void pnfs_destroy_all_layouts(struct nfs_client *);
166 void put_layout_hdr(struct pnfs_layout_hdr *lo);
167 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
168 			     const nfs4_stateid *new,
169 			     bool update_barrier);
170 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
171 				  struct pnfs_layout_hdr *lo,
172 				  struct nfs4_state *open_state);
173 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
174 				struct list_head *tmp_list,
175 				struct pnfs_layout_range *recall_range);
176 bool pnfs_roc(struct inode *ino);
177 void pnfs_roc_release(struct inode *ino);
178 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
179 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
180 void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
181 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
182 int _pnfs_return_layout(struct inode *);
183 int pnfs_ld_write_done(struct nfs_write_data *);
184 int pnfs_ld_read_done(struct nfs_read_data *);
185 
186 /* pnfs_dev.c */
187 struct nfs4_deviceid_node {
188 	struct hlist_node		node;
189 	struct hlist_node		tmpnode;
190 	const struct pnfs_layoutdriver_type *ld;
191 	const struct nfs_client		*nfs_client;
192 	struct nfs4_deviceid		deviceid;
193 	atomic_t			ref;
194 };
195 
196 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
197 struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
198 struct nfs4_deviceid_node *nfs4_unhash_put_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
199 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
200 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
201 			     const struct pnfs_layoutdriver_type *,
202 			     const struct nfs_client *,
203 			     const struct nfs4_deviceid *);
204 struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
205 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
206 void nfs4_deviceid_purge_client(const struct nfs_client *);
207 
208 static inline int lo_fail_bit(u32 iomode)
209 {
210 	return iomode == IOMODE_RW ?
211 			 NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
212 }
213 
214 static inline struct pnfs_layout_segment *
215 get_lseg(struct pnfs_layout_segment *lseg)
216 {
217 	if (lseg) {
218 		atomic_inc(&lseg->pls_refcount);
219 		smp_mb__after_atomic_inc();
220 	}
221 	return lseg;
222 }
223 
224 /* Return true if a layout driver is being used for this mountpoint */
225 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
226 {
227 	return nfss->pnfs_curr_ld != NULL;
228 }
229 
230 static inline void
231 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
232 {
233 	if (lseg) {
234 		struct pnfs_layoutdriver_type *ld;
235 
236 		ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
237 		if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
238 			set_bit(PG_PNFS_COMMIT, &req->wb_flags);
239 			req->wb_commit_lseg = get_lseg(lseg);
240 		}
241 	}
242 }
243 
244 static inline int
245 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
246 {
247 	if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
248 		return PNFS_NOT_ATTEMPTED;
249 	return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
250 }
251 
252 static inline struct list_head *
253 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
254 {
255 	struct list_head *rv;
256 
257 	if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
258 		struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
259 
260 		set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
261 		rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
262 		/* matched by ref taken when PG_PNFS_COMMIT is set */
263 		put_lseg(req->wb_commit_lseg);
264 	} else
265 		rv = mds;
266 	return rv;
267 }
268 
269 static inline void pnfs_clear_request_commit(struct nfs_page *req)
270 {
271 	if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
272 		put_lseg(req->wb_commit_lseg);
273 }
274 
275 /* Should the pNFS client commit and return the layout upon a setattr */
276 static inline bool
277 pnfs_ld_layoutret_on_setattr(struct inode *inode)
278 {
279 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
280 		return false;
281 	return NFS_SERVER(inode)->pnfs_curr_ld->flags &
282 		PNFS_LAYOUTRET_ON_SETATTR;
283 }
284 
285 static inline int pnfs_return_layout(struct inode *ino)
286 {
287 	struct nfs_inode *nfsi = NFS_I(ino);
288 	struct nfs_server *nfss = NFS_SERVER(ino);
289 
290 	if (pnfs_enabled_sb(nfss) && nfsi->layout)
291 		return _pnfs_return_layout(ino);
292 
293 	return 0;
294 }
295 
296 static inline void pnfs_pageio_init(struct nfs_pageio_descriptor *pgio,
297 				    struct inode *inode)
298 {
299 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
300 
301 	if (ld)
302 		pgio->pg_test = ld->pg_test;
303 }
304 
305 #else  /* CONFIG_NFS_V4_1 */
306 
307 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
308 {
309 }
310 
311 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
312 {
313 }
314 
315 static inline struct pnfs_layout_segment *
316 get_lseg(struct pnfs_layout_segment *lseg)
317 {
318 	return NULL;
319 }
320 
321 static inline void put_lseg(struct pnfs_layout_segment *lseg)
322 {
323 }
324 
325 static inline struct pnfs_layout_segment *
326 pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
327 		   loff_t pos, u64 count, enum pnfs_iomode access_type,
328 		   gfp_t gfp_flags)
329 {
330 	return NULL;
331 }
332 
333 static inline enum pnfs_try_status
334 pnfs_try_to_read_data(struct nfs_read_data *data,
335 		      const struct rpc_call_ops *call_ops)
336 {
337 	return PNFS_NOT_ATTEMPTED;
338 }
339 
340 static inline enum pnfs_try_status
341 pnfs_try_to_write_data(struct nfs_write_data *data,
342 		       const struct rpc_call_ops *call_ops, int how)
343 {
344 	return PNFS_NOT_ATTEMPTED;
345 }
346 
347 static inline int pnfs_return_layout(struct inode *ino)
348 {
349 	return 0;
350 }
351 
352 static inline bool
353 pnfs_ld_layoutret_on_setattr(struct inode *inode)
354 {
355 	return false;
356 }
357 
358 static inline bool
359 pnfs_roc(struct inode *ino)
360 {
361 	return false;
362 }
363 
364 static inline void
365 pnfs_roc_release(struct inode *ino)
366 {
367 }
368 
369 static inline void
370 pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
371 {
372 }
373 
374 static inline bool
375 pnfs_roc_drain(struct inode *ino, u32 *barrier)
376 {
377 	return false;
378 }
379 
380 static inline void set_pnfs_layoutdriver(struct nfs_server *s, u32 id)
381 {
382 }
383 
384 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
385 {
386 }
387 
388 static inline void pnfs_pageio_init(struct nfs_pageio_descriptor *pgio,
389 				    struct inode *inode)
390 {
391 }
392 
393 static inline void
394 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
395 {
396 }
397 
398 static inline int
399 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
400 {
401 	return PNFS_NOT_ATTEMPTED;
402 }
403 
404 static inline struct list_head *
405 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
406 {
407 	return mds;
408 }
409 
410 static inline void pnfs_clear_request_commit(struct nfs_page *req)
411 {
412 }
413 
414 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
415 {
416 	return 0;
417 }
418 
419 static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
420 {
421 }
422 #endif /* CONFIG_NFS_V4_1 */
423 
424 #endif /* FS_NFS_PNFS_H */
425