fs/nfs/objlayout/objlayout.h

   1 /*
   2  *  Data types and function declerations for interfacing with the
   3  *  pNFS standard object layout driver.
   4  *
   5  *  Copyright (C) 2007 Panasas Inc. [year of first publication]
   6  *  All rights reserved.
   7  *
   8  *  Benny Halevy <bhalevy@panasas.com>
   9  *  Boaz Harrosh <ooo@electrozaur.com>
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License version 2
  13  *  See the file COPYING included with this distribution for more details.
  14  *
  15  *  Redistribution and use in source and binary forms, with or without
  16  *  modification, are permitted provided that the following conditions
  17  *  are met:
  18  *
  19  *  1. Redistributions of source code must retain the above copyright
  20  *     notice, this list of conditions and the following disclaimer.
  21  *  2. Redistributions in binary form must reproduce the above copyright
  22  *     notice, this list of conditions and the following disclaimer in the
  23  *     documentation and/or other materials provided with the distribution.
  24  *  3. Neither the name of the Panasas company nor the names of its
  25  *     contributors may be used to endorse or promote products derived
  26  *     from this software without specific prior written permission.
  27  *
  28  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  29  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  30  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  31  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  32  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  33  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  34  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  35  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  36  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  37  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  38  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  39  */
  40
  41 #ifndef _OBJLAYOUT_H
  42 #define _OBJLAYOUT_H
  43
  44 #include <linux/nfs_fs.h>
  45 #include <linux/pnfs_osd_xdr.h>
  46 #include "../pnfs.h"
  47
  48 /*
  49  * per-inode layout
  50  */
  51 struct objlayout {
  52         struct pnfs_layout_hdr pnfs_layout;
  53
  54          /* for layout_commit */
  55         enum osd_delta_space_valid_enum {
  56                 OBJ_DSU_INIT = 0,
  57                 OBJ_DSU_VALID,
  58                 OBJ_DSU_INVALID,
  59         } delta_space_valid;
  60         s64 delta_space_used;  /* consumed by write ops */
  61
  62          /* for layout_return */
  63         spinlock_t lock;
  64         struct list_head err_list;
  65 };
  66
  67 static inline struct objlayout *
  68 OBJLAYOUT(struct pnfs_layout_hdr *lo)
  69 {
  70         return container_of(lo, struct objlayout, pnfs_layout);
  71 }
  72
  73 /*
  74  * per-I/O operation state
  75  * embedded in objects provider io_state data structure
  76  */
  77 struct objlayout_io_res {
  78         struct objlayout *objlay;
  79
  80         void *rpcdata;
  81         int status;             /* res */
  82         int committed;          /* res */
  83
  84         /* Error reporting (layout_return) */
  85         struct list_head err_list;
  86         unsigned num_comps;
  87         /* Pointer to array of error descriptors of size num_comps.
  88          * It should contain as many entries as devices in the osd_layout
  89          * that participate in the I/O. It is up to the io_engine to allocate
  90          * needed space and set num_comps.
  91          */
  92         struct pnfs_osd_ioerr *ioerrs;
  93 };
  94
  95 static inline
  96 void objlayout_init_ioerrs(struct objlayout_io_res *oir, unsigned num_comps,
  97                         struct pnfs_osd_ioerr *ioerrs, void *rpcdata,
  98                         struct pnfs_layout_hdr *pnfs_layout_type)
  99 {
 100         oir->objlay = OBJLAYOUT(pnfs_layout_type);
 101         oir->rpcdata = rpcdata;
 102         INIT_LIST_HEAD(&oir->err_list);
 103         oir->num_comps = num_comps;
 104         oir->ioerrs = ioerrs;
 105 }
 106
 107 /*
 108  * Raid engine I/O API
 109  */
 110 extern int objio_alloc_lseg(struct pnfs_layout_segment **outp,
 111         struct pnfs_layout_hdr *pnfslay,
 112         struct pnfs_layout_range *range,
 113         struct xdr_stream *xdr,
 114         gfp_t gfp_flags);
 115 extern void objio_free_lseg(struct pnfs_layout_segment *lseg);
 116
 117 /* objio_free_result will free these @oir structs received from
 118  * objlayout_{read,write}_done
 119  */
 120 extern void objio_free_result(struct objlayout_io_res *oir);
 121
 122 extern int objio_read_pagelist(struct nfs_pgio_header *rdata);
 123 extern int objio_write_pagelist(struct nfs_pgio_header *wdata, int how);
 124
 125 /*
 126  * callback API
 127  */
 128 extern void objlayout_io_set_result(struct objlayout_io_res *oir,
 129                         unsigned index, struct pnfs_osd_objid *pooid,
 130                         int osd_error, u64 offset, u64 length, bool is_write);
 131
 132 static inline void
 133 objlayout_add_delta_space_used(struct objlayout *objlay, s64 space_used)
 134 {
 135         /* If one of the I/Os errored out and the delta_space_used was
 136          * invalid we render the complete report as invalid. Protocol mandate
 137          * the DSU be accurate or not reported.
 138          */
 139         spin_lock(&objlay->lock);
 140         if (objlay->delta_space_valid != OBJ_DSU_INVALID) {
 141                 objlay->delta_space_valid = OBJ_DSU_VALID;
 142                 objlay->delta_space_used += space_used;
 143         }
 144         spin_unlock(&objlay->lock);
 145 }
 146
 147 extern void objlayout_read_done(struct objlayout_io_res *oir,
 148                                 ssize_t status, bool sync);
 149 extern void objlayout_write_done(struct objlayout_io_res *oir,
 150                                  ssize_t status, bool sync);
 151
 152 /*
 153  * exported generic objects function vectors
 154  */
 155
 156 extern struct pnfs_layout_hdr *objlayout_alloc_layout_hdr(struct inode *, gfp_t gfp_flags);
 157 extern void objlayout_free_layout_hdr(struct pnfs_layout_hdr *);
 158
 159 extern struct pnfs_layout_segment *objlayout_alloc_lseg(
 160         struct pnfs_layout_hdr *,
 161         struct nfs4_layoutget_res *,
 162         gfp_t gfp_flags);
 163 extern void objlayout_free_lseg(struct pnfs_layout_segment *);
 164
 165 extern enum pnfs_try_status objlayout_read_pagelist(
 166         struct nfs_pgio_header *);
 167
 168 extern enum pnfs_try_status objlayout_write_pagelist(
 169         struct nfs_pgio_header *,
 170         int how);
 171
 172 extern void objlayout_encode_layoutcommit(
 173         struct pnfs_layout_hdr *,
 174         struct xdr_stream *,
 175         const struct nfs4_layoutcommit_args *);
 176
 177 extern void objlayout_encode_layoutreturn(
 178         struct pnfs_layout_hdr *,
 179         struct xdr_stream *,
 180         const struct nfs4_layoutreturn_args *);
 181
 182 extern int objlayout_autologin(struct pnfs_osd_deviceaddr *deviceaddr);
 183
 184 #endif /* _OBJLAYOUT_H */