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         struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
  85         void (*free_layout_hdr) (struct pnfs_layout_hdr *);
  86
  87         struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
  88         void (*free_lseg) (struct pnfs_layout_segment *lseg);
  89
  90         /* test for nfs page cache coalescing */
  91         bool (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *);
  92
  93         /* Returns true if layoutdriver wants to divert this request to
  94          * driver's commit routine.
  95          */
  96         bool (*mark_pnfs_commit)(struct pnfs_layout_segment *lseg);
  97         struct list_head * (*choose_commit_list) (struct nfs_page *req);
  98         int (*commit_pagelist)(struct inode *inode, struct list_head *mds_pages, int how);
  99
 100         /*
 101          * Return PNFS_ATTEMPTED to indicate the layout code has attempted
 102          * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
 103          */
 104         enum pnfs_try_status (*read_pagelist) (struct nfs_read_data *nfs_data);
 105         enum pnfs_try_status (*write_pagelist) (struct nfs_write_data *nfs_data, int how);
 106
 107         void (*free_deviceid_node) (struct nfs4_deviceid_node *);
 108
 109         void (*encode_layoutreturn) (struct pnfs_layout_hdr *layoutid,
 110                                      struct xdr_stream *xdr,
 111                                      const struct nfs4_layoutreturn_args *args);
 112
 113         void (*encode_layoutcommit) (struct pnfs_layout_hdr *layoutid,
 114                                      struct xdr_stream *xdr,
 115                                      const struct nfs4_layoutcommit_args *args);
 116 };
 117
 118 struct pnfs_layout_hdr {
 119         atomic_t                plh_refcount;
 120         struct list_head        plh_layouts;   /* other client layouts */
 121         struct list_head        plh_bulk_recall; /* clnt list of bulk recalls */
 122         struct list_head        plh_segs;      /* layout segments list */
 123         nfs4_stateid            plh_stateid;
 124         atomic_t                plh_outstanding; /* number of RPCs out */
 125         unsigned long           plh_block_lgets; /* block LAYOUTGET if >0 */
 126         u32                     plh_barrier; /* ignore lower seqids */
 127         unsigned long           plh_flags;
 128         loff_t                  plh_lwb; /* last write byte for layoutcommit */
 129         struct rpc_cred         *plh_lc_cred; /* layoutcommit cred */
 130         struct inode            *plh_inode;
 131 };
 132
 133 struct pnfs_device {
 134         struct nfs4_deviceid dev_id;
 135         unsigned int  layout_type;
 136         unsigned int  mincount;
 137         struct page **pages;
 138         unsigned int  pgbase;
 139         unsigned int  pglen;
 140 };
 141
 142 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
 143 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
 144
 145 /* nfs4proc.c */
 146 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
 147                                    struct pnfs_device *dev);
 148 extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
 149 extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp);
 150
 151 /* pnfs.c */
 152 void get_layout_hdr(struct pnfs_layout_hdr *lo);
 153 void put_lseg(struct pnfs_layout_segment *lseg);
 154 struct pnfs_layout_segment *
 155 pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
 156                    loff_t pos, u64 count, enum pnfs_iomode access_type,
 157                    gfp_t gfp_flags);
 158 void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
 159 void unset_pnfs_layoutdriver(struct nfs_server *);
 160 enum pnfs_try_status pnfs_try_to_write_data(struct nfs_write_data *,
 161                                              const struct rpc_call_ops *, int);
 162 enum pnfs_try_status pnfs_try_to_read_data(struct nfs_read_data *,
 163                                             const struct rpc_call_ops *);
 164 bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req);
 165 int pnfs_layout_process(struct nfs4_layoutget *lgp);
 166 void pnfs_free_lseg_list(struct list_head *tmp_list);
 167 void pnfs_destroy_layout(struct nfs_inode *);
 168 void pnfs_destroy_all_layouts(struct nfs_client *);
 169 void put_layout_hdr(struct pnfs_layout_hdr *lo);
 170 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
 171                              const nfs4_stateid *new,
 172                              bool update_barrier);
 173 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
 174                                   struct pnfs_layout_hdr *lo,
 175                                   struct nfs4_state *open_state);
 176 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 177                                 struct list_head *tmp_list,
 178                                 struct pnfs_layout_range *recall_range);
 179 bool pnfs_roc(struct inode *ino);
 180 void pnfs_roc_release(struct inode *ino);
 181 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
 182 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
 183 void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
 184 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
 185 int _pnfs_return_layout(struct inode *);
 186 int pnfs_ld_write_done(struct nfs_write_data *);
 187 int pnfs_ld_read_done(struct nfs_read_data *);
 188
 189 /* pnfs_dev.c */
 190 struct nfs4_deviceid_node {
 191         struct hlist_node               node;
 192         struct hlist_node               tmpnode;
 193         const struct pnfs_layoutdriver_type *ld;
 194         const struct nfs_client         *nfs_client;
 195         struct nfs4_deviceid            deviceid;
 196         atomic_t                        ref;
 197 };
 198
 199 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
 200 struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 201 struct nfs4_deviceid_node *nfs4_unhash_put_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 202 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 203 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
 204                              const struct pnfs_layoutdriver_type *,
 205                              const struct nfs_client *,
 206                              const struct nfs4_deviceid *);
 207 struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
 208 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
 209 void nfs4_deviceid_purge_client(const struct nfs_client *);
 210
 211 static inline int lo_fail_bit(u32 iomode)
 212 {
 213         return iomode == IOMODE_RW ?
 214                          NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 215 }
 216
 217 static inline struct pnfs_layout_segment *
 218 get_lseg(struct pnfs_layout_segment *lseg)
 219 {
 220         if (lseg) {
 221                 atomic_inc(&lseg->pls_refcount);
 222                 smp_mb__after_atomic_inc();
 223         }
 224         return lseg;
 225 }
 226
 227 /* Return true if a layout driver is being used for this mountpoint */
 228 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
 229 {
 230         return nfss->pnfs_curr_ld != NULL;
 231 }
 232
 233 static inline void
 234 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
 235 {
 236         if (lseg) {
 237                 struct pnfs_layoutdriver_type *ld;
 238
 239                 ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
 240                 if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
 241                         set_bit(PG_PNFS_COMMIT, &req->wb_flags);
 242                         req->wb_commit_lseg = get_lseg(lseg);
 243                 }
 244         }
 245 }
 246
 247 static inline int
 248 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
 249 {
 250         if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
 251                 return PNFS_NOT_ATTEMPTED;
 252         return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
 253 }
 254
 255 static inline struct list_head *
 256 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
 257 {
 258         struct list_head *rv;
 259
 260         if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
 261                 struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
 262
 263                 set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
 264                 rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
 265                 /* matched by ref taken when PG_PNFS_COMMIT is set */
 266                 put_lseg(req->wb_commit_lseg);
 267         } else
 268                 rv = mds;
 269         return rv;
 270 }
 271
 272 static inline void pnfs_clear_request_commit(struct nfs_page *req)
 273 {
 274         if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
 275                 put_lseg(req->wb_commit_lseg);
 276 }
 277
 278 /* Should the pNFS client commit and return the layout upon a setattr */
 279 static inline bool
 280 pnfs_ld_layoutret_on_setattr(struct inode *inode)
 281 {
 282         if (!pnfs_enabled_sb(NFS_SERVER(inode)))
 283                 return false;
 284         return NFS_SERVER(inode)->pnfs_curr_ld->flags &
 285                 PNFS_LAYOUTRET_ON_SETATTR;
 286 }
 287
 288 static inline int pnfs_return_layout(struct inode *ino)
 289 {
 290         struct nfs_inode *nfsi = NFS_I(ino);
 291         struct nfs_server *nfss = NFS_SERVER(ino);
 292
 293         if (pnfs_enabled_sb(nfss) && nfsi->layout)
 294                 return _pnfs_return_layout(ino);
 295
 296         return 0;
 297 }
 298
 299 static inline void pnfs_pageio_init(struct nfs_pageio_descriptor *pgio,
 300                                     struct inode *inode)
 301 {
 302         struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
 303
 304         if (ld)
 305                 pgio->pg_test = ld->pg_test;
 306 }
 307
 308 #else  /* CONFIG_NFS_V4_1 */
 309
 310 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
 311 {
 312 }
 313
 314 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
 315 {
 316 }
 317
 318 static inline struct pnfs_layout_segment *
 319 get_lseg(struct pnfs_layout_segment *lseg)
 320 {
 321         return NULL;
 322 }
 323
 324 static inline void put_lseg(struct pnfs_layout_segment *lseg)
 325 {
 326 }
 327
 328 static inline struct pnfs_layout_segment *
 329 pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
 330                    loff_t pos, u64 count, enum pnfs_iomode access_type,
 331                    gfp_t gfp_flags)
 332 {
 333         return NULL;
 334 }
 335
 336 static inline enum pnfs_try_status
 337 pnfs_try_to_read_data(struct nfs_read_data *data,
 338                       const struct rpc_call_ops *call_ops)
 339 {
 340         return PNFS_NOT_ATTEMPTED;
 341 }
 342
 343 static inline enum pnfs_try_status
 344 pnfs_try_to_write_data(struct nfs_write_data *data,
 345                        const struct rpc_call_ops *call_ops, int how)
 346 {
 347         return PNFS_NOT_ATTEMPTED;
 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, u32 id)
 384 {
 385 }
 386
 387 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
 388 {
 389 }
 390
 391 static inline void pnfs_pageio_init(struct nfs_pageio_descriptor *pgio,
 392                                     struct inode *inode)
 393 {
 394 }
 395
 396 static inline void
 397 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
 398 {
 399 }
 400
 401 static inline int
 402 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
 403 {
 404         return PNFS_NOT_ATTEMPTED;
 405 }
 406
 407 static inline struct list_head *
 408 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
 409 {
 410         return mds;
 411 }
 412
 413 static inline void pnfs_clear_request_commit(struct nfs_page *req)
 414 {
 415 }
 416
 417 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
 418 {
 419         return 0;
 420 }
 421
 422 static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
 423 {
 424 }
 425 #endif /* CONFIG_NFS_V4_1 */
 426
 427 #endif /* FS_NFS_PNFS_H */