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 };
  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         loff_t                  plh_lwb; /* last write byte for layoutcommit */
 128         struct rpc_cred         *plh_lc_cred; /* layoutcommit cred */
 129         struct inode            *plh_inode;
 130 };
 131
 132 struct pnfs_device {
 133         struct nfs4_deviceid dev_id;
 134         unsigned int  layout_type;
 135         unsigned int  mincount;
 136         struct page **pages;
 137         unsigned int  pgbase;
 138         unsigned int  pglen;
 139 };
 140
 141 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
 142 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
 143
 144 /* nfs4proc.c */
 145 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
 146                                    struct pnfs_device *dev);
 147 extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
 148 extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp);
 149
 150 /* pnfs.c */
 151 void get_layout_hdr(struct pnfs_layout_hdr *lo);
 152 void put_lseg(struct pnfs_layout_segment *lseg);
 153 struct pnfs_layout_segment *
 154 pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
 155                    loff_t pos, u64 count, enum pnfs_iomode access_type,
 156                    gfp_t gfp_flags);
 157 void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
 158 void unset_pnfs_layoutdriver(struct nfs_server *);
 159 enum pnfs_try_status pnfs_try_to_write_data(struct nfs_write_data *,
 160                                              const struct rpc_call_ops *, int);
 161 enum pnfs_try_status pnfs_try_to_read_data(struct nfs_read_data *,
 162                                             const struct rpc_call_ops *);
 163 bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req);
 164 int pnfs_layout_process(struct nfs4_layoutget *lgp);
 165 void pnfs_free_lseg_list(struct list_head *tmp_list);
 166 void pnfs_destroy_layout(struct nfs_inode *);
 167 void pnfs_destroy_all_layouts(struct nfs_client *);
 168 void put_layout_hdr(struct pnfs_layout_hdr *lo);
 169 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
 170                              const nfs4_stateid *new,
 171                              bool update_barrier);
 172 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
 173                                   struct pnfs_layout_hdr *lo,
 174                                   struct nfs4_state *open_state);
 175 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 176                                 struct list_head *tmp_list,
 177                                 struct pnfs_layout_range *recall_range);
 178 bool pnfs_roc(struct inode *ino);
 179 void pnfs_roc_release(struct inode *ino);
 180 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
 181 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
 182 void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
 183 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
 184 int _pnfs_return_layout(struct inode *);
 185 int pnfs_ld_write_done(struct nfs_write_data *);
 186 int pnfs_ld_read_done(struct nfs_read_data *);
 187
 188 /* pnfs_dev.c */
 189 struct nfs4_deviceid_node {
 190         struct hlist_node               node;
 191         struct hlist_node               tmpnode;
 192         const struct pnfs_layoutdriver_type *ld;
 193         const struct nfs_client         *nfs_client;
 194         struct nfs4_deviceid            deviceid;
 195         atomic_t                        ref;
 196 };
 197
 198 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
 199 struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 200 struct nfs4_deviceid_node *nfs4_unhash_put_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 201 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 202 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
 203                              const struct pnfs_layoutdriver_type *,
 204                              const struct nfs_client *,
 205                              const struct nfs4_deviceid *);
 206 struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
 207 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
 208 void nfs4_deviceid_purge_client(const struct nfs_client *);
 209
 210 static inline int lo_fail_bit(u32 iomode)
 211 {
 212         return iomode == IOMODE_RW ?
 213                          NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 214 }
 215
 216 static inline struct pnfs_layout_segment *
 217 get_lseg(struct pnfs_layout_segment *lseg)
 218 {
 219         if (lseg) {
 220                 atomic_inc(&lseg->pls_refcount);
 221                 smp_mb__after_atomic_inc();
 222         }
 223         return lseg;
 224 }
 225
 226 /* Return true if a layout driver is being used for this mountpoint */
 227 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
 228 {
 229         return nfss->pnfs_curr_ld != NULL;
 230 }
 231
 232 static inline void
 233 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
 234 {
 235         if (lseg) {
 236                 struct pnfs_layoutdriver_type *ld;
 237
 238                 ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
 239                 if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
 240                         set_bit(PG_PNFS_COMMIT, &req->wb_flags);
 241                         req->wb_commit_lseg = get_lseg(lseg);
 242                 }
 243         }
 244 }
 245
 246 static inline int
 247 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
 248 {
 249         if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
 250                 return PNFS_NOT_ATTEMPTED;
 251         return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
 252 }
 253
 254 static inline struct list_head *
 255 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
 256 {
 257         struct list_head *rv;
 258
 259         if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
 260                 struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
 261
 262                 set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
 263                 rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
 264                 /* matched by ref taken when PG_PNFS_COMMIT is set */
 265                 put_lseg(req->wb_commit_lseg);
 266         } else
 267                 rv = mds;
 268         return rv;
 269 }
 270
 271 static inline void pnfs_clear_request_commit(struct nfs_page *req)
 272 {
 273         if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
 274                 put_lseg(req->wb_commit_lseg);
 275 }
 276
 277 /* Should the pNFS client commit and return the layout upon a setattr */
 278 static inline bool
 279 pnfs_ld_layoutret_on_setattr(struct inode *inode)
 280 {
 281         if (!pnfs_enabled_sb(NFS_SERVER(inode)))
 282                 return false;
 283         return NFS_SERVER(inode)->pnfs_curr_ld->flags &
 284                 PNFS_LAYOUTRET_ON_SETATTR;
 285 }
 286
 287 static inline int pnfs_return_layout(struct inode *ino)
 288 {
 289         struct nfs_inode *nfsi = NFS_I(ino);
 290         struct nfs_server *nfss = NFS_SERVER(ino);
 291
 292         if (pnfs_enabled_sb(nfss) && nfsi->layout)
 293                 return _pnfs_return_layout(ino);
 294
 295         return 0;
 296 }
 297
 298 static inline void pnfs_pageio_init(struct nfs_pageio_descriptor *pgio,
 299                                     struct inode *inode)
 300 {
 301         struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
 302
 303         if (ld)
 304                 pgio->pg_test = ld->pg_test;
 305 }
 306
 307 #else  /* CONFIG_NFS_V4_1 */
 308
 309 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
 310 {
 311 }
 312
 313 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
 314 {
 315 }
 316
 317 static inline struct pnfs_layout_segment *
 318 get_lseg(struct pnfs_layout_segment *lseg)
 319 {
 320         return NULL;
 321 }
 322
 323 static inline void put_lseg(struct pnfs_layout_segment *lseg)
 324 {
 325 }
 326
 327 static inline struct pnfs_layout_segment *
 328 pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
 329                    loff_t pos, u64 count, enum pnfs_iomode access_type,
 330                    gfp_t gfp_flags)
 331 {
 332         return NULL;
 333 }
 334
 335 static inline enum pnfs_try_status
 336 pnfs_try_to_read_data(struct nfs_read_data *data,
 337                       const struct rpc_call_ops *call_ops)
 338 {
 339         return PNFS_NOT_ATTEMPTED;
 340 }
 341
 342 static inline enum pnfs_try_status
 343 pnfs_try_to_write_data(struct nfs_write_data *data,
 344                        const struct rpc_call_ops *call_ops, int how)
 345 {
 346         return PNFS_NOT_ATTEMPTED;
 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, u32 id)
 383 {
 384 }
 385
 386 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
 387 {
 388 }
 389
 390 static inline void pnfs_pageio_init(struct nfs_pageio_descriptor *pgio,
 391                                     struct inode *inode)
 392 {
 393 }
 394
 395 static inline void
 396 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
 397 {
 398 }
 399
 400 static inline int
 401 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
 402 {
 403         return PNFS_NOT_ATTEMPTED;
 404 }
 405
 406 static inline struct list_head *
 407 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
 408 {
 409         return mds;
 410 }
 411
 412 static inline void pnfs_clear_request_commit(struct nfs_page *req)
 413 {
 414 }
 415
 416 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
 417 {
 418         return 0;
 419 }
 420
 421 static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
 422 {
 423 }
 424 #endif /* CONFIG_NFS_V4_1 */
 425
 426 #endif /* FS_NFS_PNFS_H */