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         int (*set_layoutdriver) (struct nfs_server *, const struct nfs_fh *);
  84         int (*clear_layoutdriver) (struct nfs_server *);
  85
  86         struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
  87         void (*free_layout_hdr) (struct pnfs_layout_hdr *);
  88
  89         struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
  90         void (*free_lseg) (struct pnfs_layout_segment *lseg);
  91
  92         /* test for nfs page cache coalescing */
  93         const struct nfs_pageio_ops *pg_read_ops;
  94         const struct nfs_pageio_ops *pg_write_ops;
  95
  96         /* Returns true if layoutdriver wants to divert this request to
  97          * driver's commit routine.
  98          */
  99         bool (*mark_pnfs_commit)(struct pnfs_layout_segment *lseg);
 100         struct list_head * (*choose_commit_list) (struct nfs_page *req);
 101         int (*commit_pagelist)(struct inode *inode, struct list_head *mds_pages, int how);
 102
 103         /*
 104          * Return PNFS_ATTEMPTED to indicate the layout code has attempted
 105          * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
 106          */
 107         enum pnfs_try_status (*read_pagelist) (struct nfs_read_data *nfs_data);
 108         enum pnfs_try_status (*write_pagelist) (struct nfs_write_data *nfs_data, int how);
 109
 110         void (*free_deviceid_node) (struct nfs4_deviceid_node *);
 111
 112         void (*encode_layoutreturn) (struct pnfs_layout_hdr *layoutid,
 113                                      struct xdr_stream *xdr,
 114                                      const struct nfs4_layoutreturn_args *args);
 115
 116         void (*cleanup_layoutcommit) (struct nfs4_layoutcommit_data *data);
 117
 118         void (*encode_layoutcommit) (struct pnfs_layout_hdr *layoutid,
 119                                      struct xdr_stream *xdr,
 120                                      const struct nfs4_layoutcommit_args *args);
 121 };
 122
 123 struct pnfs_layout_hdr {
 124         atomic_t                plh_refcount;
 125         struct list_head        plh_layouts;   /* other client layouts */
 126         struct list_head        plh_bulk_recall; /* clnt list of bulk recalls */
 127         struct list_head        plh_segs;      /* layout segments list */
 128         nfs4_stateid            plh_stateid;
 129         atomic_t                plh_outstanding; /* number of RPCs out */
 130         unsigned long           plh_block_lgets; /* block LAYOUTGET if >0 */
 131         u32                     plh_barrier; /* ignore lower seqids */
 132         unsigned long           plh_flags;
 133         loff_t                  plh_lwb; /* last write byte for layoutcommit */
 134         struct rpc_cred         *plh_lc_cred; /* layoutcommit cred */
 135         struct inode            *plh_inode;
 136 };
 137
 138 struct pnfs_device {
 139         struct nfs4_deviceid dev_id;
 140         unsigned int  layout_type;
 141         unsigned int  mincount;
 142         struct page **pages;
 143         unsigned int  pgbase;
 144         unsigned int  pglen;
 145 };
 146
 147 #define NFS4_PNFS_GETDEVLIST_MAXNUM 16
 148
 149 struct pnfs_devicelist {
 150         unsigned int            eof;
 151         unsigned int            num_devs;
 152         struct nfs4_deviceid    dev_id[NFS4_PNFS_GETDEVLIST_MAXNUM];
 153 };
 154
 155 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
 156 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
 157
 158 /* nfs4proc.c */
 159 extern int nfs4_proc_getdevicelist(struct nfs_server *server,
 160                                    const struct nfs_fh *fh,
 161                                    struct pnfs_devicelist *devlist);
 162 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
 163                                    struct pnfs_device *dev);
 164 extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
 165 extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp);
 166
 167 /* pnfs.c */
 168 void get_layout_hdr(struct pnfs_layout_hdr *lo);
 169 void put_lseg(struct pnfs_layout_segment *lseg);
 170
 171 bool pnfs_pageio_init_read(struct nfs_pageio_descriptor *, struct inode *);
 172 bool pnfs_pageio_init_write(struct nfs_pageio_descriptor *, struct inode *, int);
 173
 174 void set_pnfs_layoutdriver(struct nfs_server *, const struct nfs_fh *, u32);
 175 void unset_pnfs_layoutdriver(struct nfs_server *);
 176 void pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *, struct nfs_page *);
 177 int pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc);
 178 void pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *, struct nfs_page *);
 179 int pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc);
 180 bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req);
 181 int pnfs_layout_process(struct nfs4_layoutget *lgp);
 182 void pnfs_free_lseg_list(struct list_head *tmp_list);
 183 void pnfs_destroy_layout(struct nfs_inode *);
 184 void pnfs_destroy_all_layouts(struct nfs_client *);
 185 void put_layout_hdr(struct pnfs_layout_hdr *lo);
 186 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
 187                              const nfs4_stateid *new,
 188                              bool update_barrier);
 189 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
 190                                   struct pnfs_layout_hdr *lo,
 191                                   struct nfs4_state *open_state);
 192 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 193                                 struct list_head *tmp_list,
 194                                 struct pnfs_layout_range *recall_range);
 195 bool pnfs_roc(struct inode *ino);
 196 void pnfs_roc_release(struct inode *ino);
 197 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
 198 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
 199 void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
 200 void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data);
 201 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
 202 int _pnfs_return_layout(struct inode *);
 203 int pnfs_ld_write_done(struct nfs_write_data *);
 204 int pnfs_ld_read_done(struct nfs_read_data *);
 205 struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,
 206                                                struct nfs_open_context *ctx,
 207                                                loff_t pos,
 208                                                u64 count,
 209                                                enum pnfs_iomode iomode,
 210                                                gfp_t gfp_flags);
 211
 212 void nfs4_deviceid_mark_client_invalid(struct nfs_client *clp);
 213
 214 /* nfs4_deviceid_flags */
 215 enum {
 216         NFS_DEVICEID_INVALID = 0,       /* set when MDS clientid recalled */
 217 };
 218
 219 /* pnfs_dev.c */
 220 struct nfs4_deviceid_node {
 221         struct hlist_node               node;
 222         struct hlist_node               tmpnode;
 223         const struct pnfs_layoutdriver_type *ld;
 224         const struct nfs_client         *nfs_client;
 225         unsigned long                   flags;
 226         struct nfs4_deviceid            deviceid;
 227         atomic_t                        ref;
 228 };
 229
 230 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
 231 struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 232 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 233 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
 234                              const struct pnfs_layoutdriver_type *,
 235                              const struct nfs_client *,
 236                              const struct nfs4_deviceid *);
 237 struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
 238 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
 239 void nfs4_deviceid_purge_client(const struct nfs_client *);
 240
 241 static inline int lo_fail_bit(u32 iomode)
 242 {
 243         return iomode == IOMODE_RW ?
 244                          NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 245 }
 246
 247 static inline struct pnfs_layout_segment *
 248 get_lseg(struct pnfs_layout_segment *lseg)
 249 {
 250         if (lseg) {
 251                 atomic_inc(&lseg->pls_refcount);
 252                 smp_mb__after_atomic_inc();
 253         }
 254         return lseg;
 255 }
 256
 257 /* Return true if a layout driver is being used for this mountpoint */
 258 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
 259 {
 260         return nfss->pnfs_curr_ld != NULL;
 261 }
 262
 263 static inline void
 264 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
 265 {
 266         if (lseg) {
 267                 struct pnfs_layoutdriver_type *ld;
 268
 269                 ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
 270                 if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
 271                         set_bit(PG_PNFS_COMMIT, &req->wb_flags);
 272                         req->wb_commit_lseg = get_lseg(lseg);
 273                 }
 274         }
 275 }
 276
 277 static inline int
 278 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
 279 {
 280         if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
 281                 return PNFS_NOT_ATTEMPTED;
 282         return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
 283 }
 284
 285 static inline struct list_head *
 286 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
 287 {
 288         struct list_head *rv;
 289
 290         if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
 291                 struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
 292
 293                 set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
 294                 rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
 295                 /* matched by ref taken when PG_PNFS_COMMIT is set */
 296                 put_lseg(req->wb_commit_lseg);
 297         } else
 298                 rv = mds;
 299         return rv;
 300 }
 301
 302 static inline void pnfs_clear_request_commit(struct nfs_page *req)
 303 {
 304         if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
 305                 put_lseg(req->wb_commit_lseg);
 306 }
 307
 308 /* Should the pNFS client commit and return the layout upon a setattr */
 309 static inline bool
 310 pnfs_ld_layoutret_on_setattr(struct inode *inode)
 311 {
 312         if (!pnfs_enabled_sb(NFS_SERVER(inode)))
 313                 return false;
 314         return NFS_SERVER(inode)->pnfs_curr_ld->flags &
 315                 PNFS_LAYOUTRET_ON_SETATTR;
 316 }
 317
 318 static inline int pnfs_return_layout(struct inode *ino)
 319 {
 320         struct nfs_inode *nfsi = NFS_I(ino);
 321         struct nfs_server *nfss = NFS_SERVER(ino);
 322
 323         if (pnfs_enabled_sb(nfss) && nfsi->layout)
 324                 return _pnfs_return_layout(ino);
 325
 326         return 0;
 327 }
 328
 329 #else  /* CONFIG_NFS_V4_1 */
 330
 331 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
 332 {
 333 }
 334
 335 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
 336 {
 337 }
 338
 339 static inline struct pnfs_layout_segment *
 340 get_lseg(struct pnfs_layout_segment *lseg)
 341 {
 342         return NULL;
 343 }
 344
 345 static inline void put_lseg(struct pnfs_layout_segment *lseg)
 346 {
 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,
 383                                          const struct nfs_fh *mntfh, u32 id)
 384 {
 385 }
 386
 387 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
 388 {
 389 }
 390
 391 static inline bool pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode)
 392 {
 393         return false;
 394 }
 395
 396 static inline bool pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags)
 397 {
 398         return false;
 399 }
 400
 401 static inline void
 402 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
 403 {
 404 }
 405
 406 static inline int
 407 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
 408 {
 409         return PNFS_NOT_ATTEMPTED;
 410 }
 411
 412 static inline struct list_head *
 413 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
 414 {
 415         return mds;
 416 }
 417
 418 static inline void pnfs_clear_request_commit(struct nfs_page *req)
 419 {
 420 }
 421
 422 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
 423 {
 424         return 0;
 425 }
 426
 427 static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
 428 {
 429 }
 430 #endif /* CONFIG_NFS_V4_1 */
 431
 432 #endif /* FS_NFS_PNFS_H */