debian/patches/pve/0018-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 Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
   7 ---
   8  block/Makefile.objs |   1 +
   9  block/zeroinit.c    | 203 ++++++++++++++++++++++++++++++++++++++++++++
  10  2 files changed, 204 insertions(+)
  11  create mode 100644 block/zeroinit.c
  12
  13 diff --git a/block/Makefile.objs b/block/Makefile.objs
  14 index 7a81892a52..03b5763bfa 100644
  15 --- a/block/Makefile.objs
  16 +++ b/block/Makefile.objs
  17 @@ -11,6 +11,7 @@ block-obj-$(CONFIG_QED) += qed.o qed-l2-cache.o qed-table.o qed-cluster.o
  18  block-obj-$(CONFIG_QED) += qed-check.o
  19  block-obj-y += vhdx.o vhdx-endian.o vhdx-log.o
  20  block-obj-y += quorum.o
  21 +block-obj-y += zeroinit.o
  22  block-obj-y += blkdebug.o blkverify.o blkreplay.o
  23  block-obj-$(CONFIG_PARALLELS) += parallels.o
  24  block-obj-y += blklogwrites.o
  25 diff --git a/block/zeroinit.c b/block/zeroinit.c
  26 new file mode 100644
  27 index 0000000000..64c49ad0e0
  28 --- /dev/null
  29 +++ b/block/zeroinit.c
  30 @@ -0,0 +1,203 @@
  31 +/*
  32 + * Filter to fake a zero-initialized block device.
  33 + *
  34 + * Copyright (c) 2016 Wolfgang Bumiller <w.bumiller@proxmox.com>
  35 + * Copyright (c) 2016 Proxmox Server Solutions GmbH
  36 + *
  37 + * This work is licensed under the terms of the GNU GPL, version 2 or later.
  38 + * See the COPYING file in the top-level directory.
  39 + */
  40 +
  41 +#include "qemu/osdep.h"
  42 +#include "qapi/error.h"
  43 +#include "block/block_int.h"
  44 +#include "qapi/qmp/qdict.h"
  45 +#include "qapi/qmp/qstring.h"
  46 +#include "qemu/cutils.h"
  47 +#include "qemu/option.h"
  48 +
  49 +typedef struct {
  50 +    bool has_zero_init;
  51 +    int64_t extents;
  52 +} BDRVZeroinitState;
  53 +
  54 +/* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
  55 +static void zeroinit_parse_filename(const char *filename, QDict *options,
  56 +                                     Error **errp)
  57 +{
  58 +    QString *raw_path;
  59 +
  60 +    /* Parse the blkverify: prefix */
  61 +    if (!strstart(filename, "zeroinit:", &filename)) {
  62 +        /* There was no prefix; therefore, all options have to be already
  63 +           present in the QDict (except for the filename) */
  64 +        return;
  65 +    }
  66 +
  67 +    raw_path = qstring_from_str(filename);
  68 +    qdict_put(options, "x-next", raw_path);
  69 +}
  70 +
  71 +static QemuOptsList runtime_opts = {
  72 +    .name = "zeroinit",
  73 +    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
  74 +    .desc = {
  75 +        {
  76 +            .name = "x-next",
  77 +            .type = QEMU_OPT_STRING,
  78 +            .help = "[internal use only, will be removed]",
  79 +        },
  80 +        {
  81 +            .name = "x-zeroinit",
  82 +            .type = QEMU_OPT_BOOL,
  83 +            .help = "set has_initialized_zero flag",
  84 +        },
  85 +        { /* end of list */ }
  86 +    },
  87 +};
  88 +
  89 +static int zeroinit_open(BlockDriverState *bs, QDict *options, int flags,
  90 +                          Error **errp)
  91 +{
  92 +    BDRVZeroinitState *s = bs->opaque;
  93 +    QemuOpts *opts;
  94 +    Error *local_err = NULL;
  95 +    int ret;
  96 +
  97 +    s->extents = 0;
  98 +
  99 +    opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 100 +    qemu_opts_absorb_qdict(opts, options, &local_err);
 101 +    if (local_err) {
 102 +        error_propagate(errp, local_err);
 103 +        ret = -EINVAL;
 104 +        goto fail;
 105 +    }
 106 +
 107 +    /* Open the raw file */
 108 +    bs->file = bdrv_open_child(qemu_opt_get(opts, "x-next"), options, "next",
 109 +                               bs, &child_file, false, &local_err);
 110 +    if (local_err) {
 111 +        ret = -EINVAL;
 112 +        error_propagate(errp, local_err);
 113 +        goto fail;
 114 +    }
 115 +
 116 +    /* set the options */
 117 +    s->has_zero_init = qemu_opt_get_bool(opts, "x-zeroinit", true);
 118 +
 119 +    ret = 0;
 120 +fail:
 121 +    if (ret < 0) {
 122 +        bdrv_unref_child(bs, bs->file);
 123 +    }
 124 +    qemu_opts_del(opts);
 125 +    return ret;
 126 +}
 127 +
 128 +static void zeroinit_close(BlockDriverState *bs)
 129 +{
 130 +    BDRVZeroinitState *s = bs->opaque;
 131 +    (void)s;
 132 +}
 133 +
 134 +static int64_t zeroinit_getlength(BlockDriverState *bs)
 135 +{
 136 +    return bdrv_getlength(bs->file->bs);
 137 +}
 138 +
 139 +static int coroutine_fn zeroinit_co_preadv(BlockDriverState *bs,
 140 +    uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
 141 +{
 142 +    return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
 143 +}
 144 +
 145 +static int coroutine_fn zeroinit_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
 146 +                                                 int count, BdrvRequestFlags flags)
 147 +{
 148 +    BDRVZeroinitState *s = bs->opaque;
 149 +    if (offset >= s->extents)
 150 +        return 0;
 151 +    return bdrv_pwrite_zeroes(bs->file, offset, count, flags);
 152 +}
 153 +
 154 +static int coroutine_fn zeroinit_co_pwritev(BlockDriverState *bs,
 155 +    uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
 156 +{
 157 +    BDRVZeroinitState *s = bs->opaque;
 158 +    int64_t extents = offset + bytes;
 159 +    if (extents > s->extents)
 160 +        s->extents = extents;
 161 +    return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
 162 +}
 163 +
 164 +static bool zeroinit_recurse_is_first_non_filter(BlockDriverState *bs,
 165 +                                                  BlockDriverState *candidate)
 166 +{
 167 +    return bdrv_recurse_is_first_non_filter(bs->file->bs, candidate);
 168 +}
 169 +
 170 +static coroutine_fn int zeroinit_co_flush(BlockDriverState *bs)
 171 +{
 172 +    return bdrv_co_flush(bs->file->bs);
 173 +}
 174 +
 175 +static int zeroinit_has_zero_init(BlockDriverState *bs)
 176 +{
 177 +    BDRVZeroinitState *s = bs->opaque;
 178 +    return s->has_zero_init;
 179 +}
 180 +
 181 +static int coroutine_fn zeroinit_co_pdiscard(BlockDriverState *bs,
 182 +                                             int64_t offset, int count)
 183 +{
 184 +    return bdrv_co_pdiscard(bs->file, offset, count);
 185 +}
 186 +
 187 +static int zeroinit_co_truncate(BlockDriverState *bs, int64_t offset,
 188 +                             PreallocMode prealloc, Error **errp)
 189 +{
 190 +    return bdrv_co_truncate(bs->file, offset, prealloc, errp);
 191 +}
 192 +
 193 +static int zeroinit_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
 194 +{
 195 +    return bdrv_get_info(bs->file->bs, bdi);
 196 +}
 197 +
 198 +static BlockDriver bdrv_zeroinit = {
 199 +    .format_name                      = "zeroinit",
 200 +    .protocol_name                    = "zeroinit",
 201 +    .instance_size                    = sizeof(BDRVZeroinitState),
 202 +
 203 +    .bdrv_parse_filename              = zeroinit_parse_filename,
 204 +    .bdrv_file_open                   = zeroinit_open,
 205 +    .bdrv_close                       = zeroinit_close,
 206 +    .bdrv_getlength                   = zeroinit_getlength,
 207 +    .bdrv_child_perm                  = bdrv_filter_default_perms,
 208 +    .bdrv_co_flush_to_disk            = zeroinit_co_flush,
 209 +
 210 +    .bdrv_co_pwrite_zeroes            = zeroinit_co_pwrite_zeroes,
 211 +    .bdrv_co_pwritev                  = zeroinit_co_pwritev,
 212 +    .bdrv_co_preadv                   = zeroinit_co_preadv,
 213 +    .bdrv_co_flush                    = zeroinit_co_flush,
 214 +
 215 +    .is_filter                        = true,
 216 +    .bdrv_recurse_is_first_non_filter = zeroinit_recurse_is_first_non_filter,
 217 +
 218 +    .bdrv_has_zero_init               = zeroinit_has_zero_init,
 219 +
 220 +    .bdrv_co_block_status             = bdrv_co_block_status_from_file,
 221 +
 222 +    .bdrv_co_pdiscard                 = zeroinit_co_pdiscard,
 223 +
 224 +    .bdrv_co_truncate                 = zeroinit_co_truncate,
 225 +    .bdrv_get_info                    = zeroinit_get_info,
 226 +};
 227 +
 228 +static void bdrv_zeroinit_init(void)
 229 +{
 230 +    bdrv_register(&bdrv_zeroinit);
 231 +}
 232 +
 233 +block_init(bdrv_zeroinit_init);
 234 --
 235 2.20.1
 236