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 <bharrosh@panasas.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_state {
  78         struct pnfs_layout_segment *lseg;
  79
  80         struct page **pages;
  81         unsigned pgbase;
  82         unsigned nr_pages;
  83         unsigned long count;
  84         loff_t offset;
  85         bool sync;
  86
  87         void *rpcdata;
  88         int status;             /* res */
  89         int eof;                /* res */
  90         int committed;          /* res */
  91
  92         /* Error reporting (layout_return) */
  93         struct list_head err_list;
  94         unsigned num_comps;
  95         /* Pointer to array of error descriptors of size num_comps.
  96          * It should contain as many entries as devices in the osd_layout
  97          * that participate in the I/O. It is up to the io_engine to allocate
  98          * needed space and set num_comps.
  99          */
 100         struct pnfs_osd_ioerr *ioerrs;
 101 };
 102
 103 /*
 104  * Raid engine I/O API
 105  */
 106 extern int objio_alloc_lseg(struct pnfs_layout_segment **outp,
 107         struct pnfs_layout_hdr *pnfslay,
 108         struct pnfs_layout_range *range,
 109         struct xdr_stream *xdr,
 110         gfp_t gfp_flags);
 111 extern void objio_free_lseg(struct pnfs_layout_segment *lseg);
 112
 113 extern int objio_alloc_io_state(
 114         struct pnfs_layout_segment *lseg,
 115         struct objlayout_io_state **outp,
 116         gfp_t gfp_flags);
 117 extern void objio_free_io_state(struct objlayout_io_state *state);
 118
 119 extern ssize_t objio_read_pagelist(struct objlayout_io_state *ol_state);
 120 extern ssize_t objio_write_pagelist(struct objlayout_io_state *ol_state,
 121                                     bool stable);
 122
 123 /*
 124  * callback API
 125  */
 126 extern void objlayout_io_set_result(struct objlayout_io_state *state,
 127                         unsigned index, struct pnfs_osd_objid *pooid,
 128                         int osd_error, u64 offset, u64 length, bool is_write);
 129
 130 static inline void
 131 objlayout_add_delta_space_used(struct objlayout_io_state *state, s64 space_used)
 132 {
 133         struct objlayout *objlay = OBJLAYOUT(state->lseg->pls_layout);
 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_state *state,
 148                                 ssize_t status, bool sync);
 149 extern void objlayout_write_done(struct objlayout_io_state *state,
 150                                  ssize_t status, bool sync);
 151
 152 extern int objlayout_get_deviceinfo(struct pnfs_layout_hdr *pnfslay,
 153         struct nfs4_deviceid *d_id, struct pnfs_osd_deviceaddr **deviceaddr,
 154         gfp_t gfp_flags);
 155 extern void objlayout_put_deviceinfo(struct pnfs_osd_deviceaddr *deviceaddr);
 156
 157 /*
 158  * exported generic objects function vectors
 159  */
 160
 161 extern struct pnfs_layout_hdr *objlayout_alloc_layout_hdr(struct inode *, gfp_t gfp_flags);
 162 extern void objlayout_free_layout_hdr(struct pnfs_layout_hdr *);
 163
 164 extern struct pnfs_layout_segment *objlayout_alloc_lseg(
 165         struct pnfs_layout_hdr *,
 166         struct nfs4_layoutget_res *,
 167         gfp_t gfp_flags);
 168 extern void objlayout_free_lseg(struct pnfs_layout_segment *);
 169
 170 extern enum pnfs_try_status objlayout_read_pagelist(
 171         struct nfs_read_data *);
 172
 173 extern enum pnfs_try_status objlayout_write_pagelist(
 174         struct nfs_write_data *,
 175         int how);
 176
 177 extern void objlayout_encode_layoutcommit(
 178         struct pnfs_layout_hdr *,
 179         struct xdr_stream *,
 180         const struct nfs4_layoutcommit_args *);
 181
 182 extern void objlayout_encode_layoutreturn(
 183         struct pnfs_layout_hdr *,
 184         struct xdr_stream *,
 185         const struct nfs4_layoutreturn_args *);
 186
 187 #endif /* _OBJLAYOUT_H */