debian/patches/pve/0019-PVE-block-add-the-zeroinit-block-driver-filter.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Wolfgang Bumiller <w.bumiller@proxmox.com>
   3 Date: Thu, 17 Mar 2016 11:33:37 +0100
   4 Subject: [PATCH] PVE: block: add the zeroinit block driver filter
   5
   6 ---
   7  block/Makefile.objs |   1 +
   8  block/zeroinit.c    | 203 ++++++++++++++++++++++++++++++++++++++++++++++++++++
   9  2 files changed, 204 insertions(+)
  10  create mode 100644 block/zeroinit.c
  11
  12 diff --git a/block/Makefile.objs b/block/Makefile.objs
  13 index c8337bf186..c00f0b32d6 100644
  14 --- a/block/Makefile.objs
  15 +++ b/block/Makefile.objs
  16 @@ -4,6 +4,7 @@ block-obj-y += qed.o qed-l2-cache.o qed-table.o qed-cluster.o
  17  block-obj-y += qed-check.o
  18  block-obj-y += vhdx.o vhdx-endian.o vhdx-log.o
  19  block-obj-y += quorum.o
  20 +block-obj-y += zeroinit.o
  21  block-obj-y += parallels.o blkdebug.o blkverify.o blkreplay.o
  22  block-obj-y += blklogwrites.o
  23  block-obj-y += block-backend.o snapshot.o qapi.o
  24 diff --git a/block/zeroinit.c b/block/zeroinit.c
  25 new file mode 100644
  26 index 0000000000..64c49ad0e0
  27 --- /dev/null
  28 +++ b/block/zeroinit.c
  29 @@ -0,0 +1,203 @@
  30 +/*
  31 + * Filter to fake a zero-initialized block device.
  32 + *
  33 + * Copyright (c) 2016 Wolfgang Bumiller <w.bumiller@proxmox.com>
  34 + * Copyright (c) 2016 Proxmox Server Solutions GmbH
  35 + *
  36 + * This work is licensed under the terms of the GNU GPL, version 2 or later.
  37 + * See the COPYING file in the top-level directory.
  38 + */
  39 +
  40 +#include "qemu/osdep.h"
  41 +#include "qapi/error.h"
  42 +#include "block/block_int.h"
  43 +#include "qapi/qmp/qdict.h"
  44 +#include "qapi/qmp/qstring.h"
  45 +#include "qemu/cutils.h"
  46 +#include "qemu/option.h"
  47 +
  48 +typedef struct {
  49 +    bool has_zero_init;
  50 +    int64_t extents;
  51 +} BDRVZeroinitState;
  52 +
  53 +/* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
  54 +static void zeroinit_parse_filename(const char *filename, QDict *options,
  55 +                                     Error **errp)
  56 +{
  57 +    QString *raw_path;
  58 +
  59 +    /* Parse the blkverify: prefix */
  60 +    if (!strstart(filename, "zeroinit:", &filename)) {
  61 +        /* There was no prefix; therefore, all options have to be already
  62 +           present in the QDict (except for the filename) */
  63 +        return;
  64 +    }
  65 +
  66 +    raw_path = qstring_from_str(filename);
  67 +    qdict_put(options, "x-next", raw_path);
  68 +}
  69 +
  70 +static QemuOptsList runtime_opts = {
  71 +    .name = "zeroinit",
  72 +    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
  73 +    .desc = {
  74 +        {
  75 +            .name = "x-next",
  76 +            .type = QEMU_OPT_STRING,
  77 +            .help = "[internal use only, will be removed]",
  78 +        },
  79 +        {
  80 +            .name = "x-zeroinit",
  81 +            .type = QEMU_OPT_BOOL,
  82 +            .help = "set has_initialized_zero flag",
  83 +        },
  84 +        { /* end of list */ }
  85 +    },
  86 +};
  87 +
  88 +static int zeroinit_open(BlockDriverState *bs, QDict *options, int flags,
  89 +                          Error **errp)
  90 +{
  91 +    BDRVZeroinitState *s = bs->opaque;
  92 +    QemuOpts *opts;
  93 +    Error *local_err = NULL;
  94 +    int ret;
  95 +
  96 +    s->extents = 0;
  97 +
  98 +    opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
  99 +    qemu_opts_absorb_qdict(opts, options, &local_err);
 100 +    if (local_err) {
 101 +        error_propagate(errp, local_err);
 102 +        ret = -EINVAL;
 103 +        goto fail;
 104 +    }
 105 +
 106 +    /* Open the raw file */
 107 +    bs->file = bdrv_open_child(qemu_opt_get(opts, "x-next"), options, "next",
 108 +                               bs, &child_file, false, &local_err);
 109 +    if (local_err) {
 110 +        ret = -EINVAL;
 111 +        error_propagate(errp, local_err);
 112 +        goto fail;
 113 +    }
 114 +
 115 +    /* set the options */
 116 +    s->has_zero_init = qemu_opt_get_bool(opts, "x-zeroinit", true);
 117 +
 118 +    ret = 0;
 119 +fail:
 120 +    if (ret < 0) {
 121 +        bdrv_unref_child(bs, bs->file);
 122 +    }
 123 +    qemu_opts_del(opts);
 124 +    return ret;
 125 +}
 126 +
 127 +static void zeroinit_close(BlockDriverState *bs)
 128 +{
 129 +    BDRVZeroinitState *s = bs->opaque;
 130 +    (void)s;
 131 +}
 132 +
 133 +static int64_t zeroinit_getlength(BlockDriverState *bs)
 134 +{
 135 +    return bdrv_getlength(bs->file->bs);
 136 +}
 137 +
 138 +static int coroutine_fn zeroinit_co_preadv(BlockDriverState *bs,
 139 +    uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
 140 +{
 141 +    return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
 142 +}
 143 +
 144 +static int coroutine_fn zeroinit_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
 145 +                                                 int count, BdrvRequestFlags flags)
 146 +{
 147 +    BDRVZeroinitState *s = bs->opaque;
 148 +    if (offset >= s->extents)
 149 +        return 0;
 150 +    return bdrv_pwrite_zeroes(bs->file, offset, count, flags);
 151 +}
 152 +
 153 +static int coroutine_fn zeroinit_co_pwritev(BlockDriverState *bs,
 154 +    uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
 155 +{
 156 +    BDRVZeroinitState *s = bs->opaque;
 157 +    int64_t extents = offset + bytes;
 158 +    if (extents > s->extents)
 159 +        s->extents = extents;
 160 +    return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
 161 +}
 162 +
 163 +static bool zeroinit_recurse_is_first_non_filter(BlockDriverState *bs,
 164 +                                                  BlockDriverState *candidate)
 165 +{
 166 +    return bdrv_recurse_is_first_non_filter(bs->file->bs, candidate);
 167 +}
 168 +
 169 +static coroutine_fn int zeroinit_co_flush(BlockDriverState *bs)
 170 +{
 171 +    return bdrv_co_flush(bs->file->bs);
 172 +}
 173 +
 174 +static int zeroinit_has_zero_init(BlockDriverState *bs)
 175 +{
 176 +    BDRVZeroinitState *s = bs->opaque;
 177 +    return s->has_zero_init;
 178 +}
 179 +
 180 +static int coroutine_fn zeroinit_co_pdiscard(BlockDriverState *bs,
 181 +                                             int64_t offset, int count)
 182 +{
 183 +    return bdrv_co_pdiscard(bs->file, offset, count);
 184 +}
 185 +
 186 +static int zeroinit_co_truncate(BlockDriverState *bs, int64_t offset,
 187 +                             PreallocMode prealloc, Error **errp)
 188 +{
 189 +    return bdrv_co_truncate(bs->file, offset, prealloc, errp);
 190 +}
 191 +
 192 +static int zeroinit_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
 193 +{
 194 +    return bdrv_get_info(bs->file->bs, bdi);
 195 +}
 196 +
 197 +static BlockDriver bdrv_zeroinit = {
 198 +    .format_name                      = "zeroinit",
 199 +    .protocol_name                    = "zeroinit",
 200 +    .instance_size                    = sizeof(BDRVZeroinitState),
 201 +
 202 +    .bdrv_parse_filename              = zeroinit_parse_filename,
 203 +    .bdrv_file_open                   = zeroinit_open,
 204 +    .bdrv_close                       = zeroinit_close,
 205 +    .bdrv_getlength                   = zeroinit_getlength,
 206 +    .bdrv_child_perm                  = bdrv_filter_default_perms,
 207 +    .bdrv_co_flush_to_disk            = zeroinit_co_flush,
 208 +
 209 +    .bdrv_co_pwrite_zeroes            = zeroinit_co_pwrite_zeroes,
 210 +    .bdrv_co_pwritev                  = zeroinit_co_pwritev,
 211 +    .bdrv_co_preadv                   = zeroinit_co_preadv,
 212 +    .bdrv_co_flush                    = zeroinit_co_flush,
 213 +
 214 +    .is_filter                        = true,
 215 +    .bdrv_recurse_is_first_non_filter = zeroinit_recurse_is_first_non_filter,
 216 +
 217 +    .bdrv_has_zero_init               = zeroinit_has_zero_init,
 218 +
 219 +    .bdrv_co_block_status             = bdrv_co_block_status_from_file,
 220 +
 221 +    .bdrv_co_pdiscard                 = zeroinit_co_pdiscard,
 222 +
 223 +    .bdrv_co_truncate                 = zeroinit_co_truncate,
 224 +    .bdrv_get_info                    = zeroinit_get_info,
 225 +};
 226 +
 227 +static void bdrv_zeroinit_init(void)
 228 +{
 229 +    bdrv_register(&bdrv_zeroinit);
 230 +}
 231 +
 232 +block_init(bdrv_zeroinit_init);
 233 --
 234 2.11.0
 235