fs/nfs/pnfs.h

   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 */