debian/patches/pve/0023-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] block: add the zeroinit block driver filter
   5
   6 ---
   7  block/Makefile.objs |   1 +
   8  block/zeroinit.c    | 202 ++++++++++++++++++++++++++++++++++++++++++++++++++++
   9  2 files changed, 203 insertions(+)
  10  create mode 100644 block/zeroinit.c
  11
  12 diff --git a/block/Makefile.objs b/block/Makefile.objs
  13 index 6eaf78a046..823e60cda6 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 += block-backend.o snapshot.o qapi.o
  23  block-obj-$(CONFIG_WIN32) += file-win32.o win32-aio.o
  24 diff --git a/block/zeroinit.c b/block/zeroinit.c
  25 new file mode 100644
  26 index 0000000000..37f588f75c
  27 --- /dev/null
  28 +++ b/block/zeroinit.c
  29 @@ -0,0 +1,202 @@
  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 +
  47 +typedef struct {
  48 +    bool has_zero_init;
  49 +    int64_t extents;
  50 +} BDRVZeroinitState;
  51 +
  52 +/* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
  53 +static void zeroinit_parse_filename(const char *filename, QDict *options,
  54 +                                     Error **errp)
  55 +{
  56 +    QString *raw_path;
  57 +
  58 +    /* Parse the blkverify: prefix */
  59 +    if (!strstart(filename, "zeroinit:", &filename)) {
  60 +        /* There was no prefix; therefore, all options have to be already
  61 +           present in the QDict (except for the filename) */
  62 +        return;
  63 +    }
  64 +
  65 +    raw_path = qstring_from_str(filename);
  66 +    qdict_put(options, "x-next", raw_path);
  67 +}
  68 +
  69 +static QemuOptsList runtime_opts = {
  70 +    .name = "zeroinit",
  71 +    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
  72 +    .desc = {
  73 +        {
  74 +            .name = "x-next",
  75 +            .type = QEMU_OPT_STRING,
  76 +            .help = "[internal use only, will be removed]",
  77 +        },
  78 +        {
  79 +            .name = "x-zeroinit",
  80 +            .type = QEMU_OPT_BOOL,
  81 +            .help = "set has_initialized_zero flag",
  82 +        },
  83 +        { /* end of list */ }
  84 +    },
  85 +};
  86 +
  87 +static int zeroinit_open(BlockDriverState *bs, QDict *options, int flags,
  88 +                          Error **errp)
  89 +{
  90 +    BDRVZeroinitState *s = bs->opaque;
  91 +    QemuOpts *opts;
  92 +    Error *local_err = NULL;
  93 +    int ret;
  94 +
  95 +    s->extents = 0;
  96 +
  97 +    opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
  98 +    qemu_opts_absorb_qdict(opts, options, &local_err);
  99 +    if (local_err) {
 100 +        error_propagate(errp, local_err);
 101 +        ret = -EINVAL;
 102 +        goto fail;
 103 +    }
 104 +
 105 +    /* Open the raw file */
 106 +    bs->file = bdrv_open_child(qemu_opt_get(opts, "x-next"), options, "next",
 107 +                               bs, &child_file, false, &local_err);
 108 +    if (local_err) {
 109 +        ret = -EINVAL;
 110 +        error_propagate(errp, local_err);
 111 +        goto fail;
 112 +    }
 113 +
 114 +    /* set the options */
 115 +    s->has_zero_init = qemu_opt_get_bool(opts, "x-zeroinit", true);
 116 +
 117 +    ret = 0;
 118 +fail:
 119 +    if (ret < 0) {
 120 +        bdrv_unref_child(bs, bs->file);
 121 +    }
 122 +    qemu_opts_del(opts);
 123 +    return ret;
 124 +}
 125 +
 126 +static void zeroinit_close(BlockDriverState *bs)
 127 +{
 128 +    BDRVZeroinitState *s = bs->opaque;
 129 +    (void)s;
 130 +}
 131 +
 132 +static int64_t zeroinit_getlength(BlockDriverState *bs)
 133 +{
 134 +    return bdrv_getlength(bs->file->bs);
 135 +}
 136 +
 137 +static int coroutine_fn zeroinit_co_preadv(BlockDriverState *bs,
 138 +    uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
 139 +{
 140 +    return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
 141 +}
 142 +
 143 +static int coroutine_fn zeroinit_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
 144 +                                                 int count, BdrvRequestFlags flags)
 145 +{
 146 +    BDRVZeroinitState *s = bs->opaque;
 147 +    if (offset >= s->extents)
 148 +        return 0;
 149 +    return bdrv_pwrite_zeroes(bs->file, offset, count, flags);
 150 +}
 151 +
 152 +static int coroutine_fn zeroinit_co_pwritev(BlockDriverState *bs,
 153 +    uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
 154 +{
 155 +    BDRVZeroinitState *s = bs->opaque;
 156 +    int64_t extents = offset + bytes;
 157 +    if (extents > s->extents)
 158 +        s->extents = extents;
 159 +    return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
 160 +}
 161 +
 162 +static bool zeroinit_recurse_is_first_non_filter(BlockDriverState *bs,
 163 +                                                  BlockDriverState *candidate)
 164 +{
 165 +    return bdrv_recurse_is_first_non_filter(bs->file->bs, candidate);
 166 +}
 167 +
 168 +static coroutine_fn int zeroinit_co_flush(BlockDriverState *bs)
 169 +{
 170 +    return bdrv_co_flush(bs->file->bs);
 171 +}
 172 +
 173 +static int zeroinit_has_zero_init(BlockDriverState *bs)
 174 +{
 175 +    BDRVZeroinitState *s = bs->opaque;
 176 +    return s->has_zero_init;
 177 +}
 178 +
 179 +static int coroutine_fn zeroinit_co_pdiscard(BlockDriverState *bs,
 180 +                                             int64_t offset, int count)
 181 +{
 182 +    return bdrv_co_pdiscard(bs->file->bs, offset, count);
 183 +}
 184 +
 185 +static int zeroinit_truncate(BlockDriverState *bs, int64_t offset,
 186 +                             PreallocMode prealloc, Error **errp)
 187 +{
 188 +    return bdrv_truncate(bs->file, offset, prealloc, errp);
 189 +}
 190 +
 191 +static int zeroinit_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
 192 +{
 193 +    return bdrv_get_info(bs->file->bs, bdi);
 194 +}
 195 +
 196 +static BlockDriver bdrv_zeroinit = {
 197 +    .format_name                      = "zeroinit",
 198 +    .protocol_name                    = "zeroinit",
 199 +    .instance_size                    = sizeof(BDRVZeroinitState),
 200 +
 201 +    .bdrv_parse_filename              = zeroinit_parse_filename,
 202 +    .bdrv_file_open                   = zeroinit_open,
 203 +    .bdrv_close                       = zeroinit_close,
 204 +    .bdrv_getlength                   = zeroinit_getlength,
 205 +    .bdrv_child_perm                  = bdrv_filter_default_perms,
 206 +    .bdrv_co_flush_to_disk            = zeroinit_co_flush,
 207 +
 208 +    .bdrv_co_pwrite_zeroes            = zeroinit_co_pwrite_zeroes,
 209 +    .bdrv_co_pwritev                  = zeroinit_co_pwritev,
 210 +    .bdrv_co_preadv                   = zeroinit_co_preadv,
 211 +    .bdrv_co_flush                    = zeroinit_co_flush,
 212 +
 213 +    .is_filter                        = true,
 214 +    .bdrv_recurse_is_first_non_filter = zeroinit_recurse_is_first_non_filter,
 215 +
 216 +    .bdrv_has_zero_init = zeroinit_has_zero_init,
 217 +
 218 +    .bdrv_co_get_block_status = bdrv_co_get_block_status_from_file,
 219 +
 220 +    .bdrv_co_pdiscard = zeroinit_co_pdiscard,
 221 +
 222 +    .bdrv_truncate = zeroinit_truncate,
 223 +    .bdrv_get_info = zeroinit_get_info,
 224 +};
 225 +
 226 +static void bdrv_zeroinit_init(void)
 227 +{
 228 +    bdrv_register(&bdrv_zeroinit);
 229 +}
 230 +
 231 +block_init(bdrv_zeroinit_init);
 232 --
 233 2.11.0
 234