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 };
  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 */