LXR linux/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 */
  51struct 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
  67static inline struct objlayout *
  68OBJLAYOUT(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 */
  77struct 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
  95static inline
  96void 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 */
 110extern 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);
 115extern 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 */
 120extern void objio_free_result(struct objlayout_io_res *oir);
 121
 122extern int objio_read_pagelist(struct nfs_read_data *rdata);
 123extern int objio_write_pagelist(struct nfs_write_data *wdata, int how);
 124
 125/*
 126 * callback API
 127 */
 128extern 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
 132static inline void
 133objlayout_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
 147extern void objlayout_read_done(struct objlayout_io_res *oir,
 148                                ssize_t status, bool sync);
 149extern void objlayout_write_done(struct objlayout_io_res *oir,
 150                                 ssize_t status, bool sync);
 151
 152extern 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);
 155extern void objlayout_put_deviceinfo(struct pnfs_osd_deviceaddr *deviceaddr);
 156
 157/*
 158 * exported generic objects function vectors
 159 */
 160
 161extern struct pnfs_layout_hdr *objlayout_alloc_layout_hdr(struct inode *, gfp_t gfp_flags);
 162extern void objlayout_free_layout_hdr(struct pnfs_layout_hdr *);
 163
 164extern struct pnfs_layout_segment *objlayout_alloc_lseg(
 165        struct pnfs_layout_hdr *,
 166        struct nfs4_layoutget_res *,
 167        gfp_t gfp_flags);
 168extern void objlayout_free_lseg(struct pnfs_layout_segment *);
 169
 170extern enum pnfs_try_status objlayout_read_pagelist(
 171        struct nfs_read_data *);
 172
 173extern enum pnfs_try_status objlayout_write_pagelist(
 174        struct nfs_write_data *,
 175        int how);
 176
 177extern void objlayout_encode_layoutcommit(
 178        struct pnfs_layout_hdr *,
 179        struct xdr_stream *,
 180        const struct nfs4_layoutcommit_args *);
 181
 182extern void objlayout_encode_layoutreturn(
 183        struct pnfs_layout_hdr *,
 184        struct xdr_stream *,
 185        const struct nfs4_layoutreturn_args *);
 186
 187extern int objlayout_autologin(struct pnfs_osd_deviceaddr *deviceaddr);
 188
 189#endif /* _OBJLAYOUT_H */
 190