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 void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg);
 182 int pnfs_layout_process(struct nfs4_layoutget *lgp);
 183 void pnfs_free_lseg_list(struct list_head *tmp_list);
 184 void pnfs_destroy_layout(struct nfs_inode *);
 185 void pnfs_destroy_all_layouts(struct nfs_client *);
 186 void put_layout_hdr(struct pnfs_layout_hdr *lo);
 187 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
 188                              const nfs4_stateid *new,
 189                              bool update_barrier);
 190 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
 191                                   struct pnfs_layout_hdr *lo,
 192                                   struct nfs4_state *open_state);
 193 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 194                                 struct list_head *tmp_list,
 195                                 struct pnfs_layout_range *recall_range);
 196 bool pnfs_roc(struct inode *ino);
 197 void pnfs_roc_release(struct inode *ino);
 198 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
 199 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
 200 void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
 201 void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data);
 202 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
 203 int _pnfs_return_layout(struct inode *);
 204 void pnfs_ld_write_done(struct nfs_write_data *);
 205 void pnfs_ld_read_done(struct nfs_read_data *);
 206 struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,
 207                                                struct nfs_open_context *ctx,
 208                                                loff_t pos,
 209                                                u64 count,
 210                                                enum pnfs_iomode iomode,
 211                                                gfp_t gfp_flags);
 212
 213 void nfs4_deviceid_mark_client_invalid(struct nfs_client *clp);
 214
 215 /* nfs4_deviceid_flags */
 216 enum {
 217         NFS_DEVICEID_INVALID = 0,       /* set when MDS clientid recalled */
 218 };
 219
 220 /* pnfs_dev.c */
 221 struct nfs4_deviceid_node {
 222         struct hlist_node               node;
 223         struct hlist_node               tmpnode;
 224         const struct pnfs_layoutdriver_type *ld;
 225         const struct nfs_client         *nfs_client;
 226         unsigned long                   flags;
 227         struct nfs4_deviceid            deviceid;
 228         atomic_t                        ref;
 229 };
 230
 231 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
 232 struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 233 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 234 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
 235                              const struct pnfs_layoutdriver_type *,
 236                              const struct nfs_client *,
 237                              const struct nfs4_deviceid *);
 238 struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
 239 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
 240 void nfs4_deviceid_purge_client(const struct nfs_client *);
 241
 242 static inline int lo_fail_bit(u32 iomode)
 243 {
 244         return iomode == IOMODE_RW ?
 245                          NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 246 }
 247
 248 static inline struct pnfs_layout_segment *
 249 get_lseg(struct pnfs_layout_segment *lseg)
 250 {
 251         if (lseg) {
 252                 atomic_inc(&lseg->pls_refcount);
 253                 smp_mb__after_atomic_inc();
 254         }
 255         return lseg;
 256 }
 257
 258 /* Return true if a layout driver is being used for this mountpoint */
 259 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
 260 {
 261         return nfss->pnfs_curr_ld != NULL;
 262 }
 263
 264 static inline void
 265 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
 266 {
 267         if (lseg) {
 268                 struct pnfs_layoutdriver_type *ld;
 269
 270                 ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
 271                 if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
 272                         set_bit(PG_PNFS_COMMIT, &req->wb_flags);
 273                         req->wb_commit_lseg = get_lseg(lseg);
 274                 }
 275         }
 276 }
 277
 278 static inline int
 279 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
 280 {
 281         if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
 282                 return PNFS_NOT_ATTEMPTED;
 283         return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
 284 }
 285
 286 static inline struct list_head *
 287 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
 288 {
 289         struct list_head *rv;
 290
 291         if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
 292                 struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
 293
 294                 set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
 295                 rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
 296                 /* matched by ref taken when PG_PNFS_COMMIT is set */
 297                 put_lseg(req->wb_commit_lseg);
 298         } else
 299                 rv = mds;
 300         return rv;
 301 }
 302
 303 static inline void pnfs_clear_request_commit(struct nfs_page *req)
 304 {
 305         if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
 306                 put_lseg(req->wb_commit_lseg);
 307 }
 308
 309 /* Should the pNFS client commit and return the layout upon a setattr */
 310 static inline bool
 311 pnfs_ld_layoutret_on_setattr(struct inode *inode)
 312 {
 313         if (!pnfs_enabled_sb(NFS_SERVER(inode)))
 314                 return false;
 315         return NFS_SERVER(inode)->pnfs_curr_ld->flags &
 316                 PNFS_LAYOUTRET_ON_SETATTR;
 317 }
 318
 319 static inline int pnfs_return_layout(struct inode *ino)
 320 {
 321         struct nfs_inode *nfsi = NFS_I(ino);
 322         struct nfs_server *nfss = NFS_SERVER(ino);
 323
 324         if (pnfs_enabled_sb(nfss) && nfsi->layout)
 325                 return _pnfs_return_layout(ino);
 326
 327         return 0;
 328 }
 329
 330 #else  /* CONFIG_NFS_V4_1 */
 331
 332 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
 333 {
 334 }
 335
 336 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
 337 {
 338 }
 339
 340 static inline struct pnfs_layout_segment *
 341 get_lseg(struct pnfs_layout_segment *lseg)
 342 {
 343         return NULL;
 344 }
 345
 346 static inline void put_lseg(struct pnfs_layout_segment *lseg)
 347 {
 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,
 384                                          const struct nfs_fh *mntfh, u32 id)
 385 {
 386 }
 387
 388 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
 389 {
 390 }
 391
 392 static inline bool pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode)
 393 {
 394         return false;
 395 }
 396
 397 static inline bool pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags)
 398 {
 399         return false;
 400 }
 401
 402 static inline void
 403 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
 404 {
 405 }
 406
 407 static inline int
 408 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
 409 {
 410         return PNFS_NOT_ATTEMPTED;
 411 }
 412
 413 static inline struct list_head *
 414 pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
 415 {
 416         return mds;
 417 }
 418
 419 static inline void pnfs_clear_request_commit(struct nfs_page *req)
 420 {
 421 }
 422
 423 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
 424 {
 425         return 0;
 426 }
 427
 428 static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
 429 {
 430 }
 431 #endif /* CONFIG_NFS_V4_1 */
 432
 433 #endif /* FS_NFS_PNFS_H */