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: Mon, 6 Apr 2020 12:16:47 +0200
   4 Subject: [PATCH] PVE: block: add the zeroinit block driver filter
   5
   6 Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
   7 [adapt to changed function signatures]
   8 Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
   9 ---
  10  block/meson.build |   1 +
  11  block/zeroinit.c  | 196 ++++++++++++++++++++++++++++++++++++++++++++++
  12  2 files changed, 197 insertions(+)
  13  create mode 100644 block/zeroinit.c
  14
  15 diff --git a/block/meson.build b/block/meson.build
  16 index 0b2a60c99b..9451fc3ccd 100644
  17 --- a/block/meson.build
  18 +++ b/block/meson.build
  19 @@ -43,6 +43,7 @@ block_ss.add(files(
  20    'vmdk.c',
  21    'vpc.c',
  22    'write-threshold.c',
  23 +  'zeroinit.c',
  24  ), zstd, zlib, gnutls)
  25
  26  softmmu_ss.add(when: 'CONFIG_TCG', if_true: files('blkreplay.c'))
  27 diff --git a/block/zeroinit.c b/block/zeroinit.c
  28 new file mode 100644
  29 index 0000000000..20ee611f22
  30 --- /dev/null
  31 +++ b/block/zeroinit.c
  32 @@ -0,0 +1,196 @@
  33 +/*
  34 + * Filter to fake a zero-initialized block device.
  35 + *
  36 + * Copyright (c) 2016 Wolfgang Bumiller <w.bumiller@proxmox.com>
  37 + * Copyright (c) 2016 Proxmox Server Solutions GmbH
  38 + *
  39 + * This work is licensed under the terms of the GNU GPL, version 2 or later.
  40 + * See the COPYING file in the top-level directory.
  41 + */
  42 +
  43 +#include "qemu/osdep.h"
  44 +#include "qapi/error.h"
  45 +#include "block/block_int.h"
  46 +#include "qapi/qmp/qdict.h"
  47 +#include "qapi/qmp/qstring.h"
  48 +#include "qemu/cutils.h"
  49 +#include "qemu/option.h"
  50 +#include "qemu/module.h"
  51 +
  52 +typedef struct {
  53 +    bool has_zero_init;
  54 +    int64_t extents;
  55 +} BDRVZeroinitState;
  56 +
  57 +/* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
  58 +static void zeroinit_parse_filename(const char *filename, QDict *options,
  59 +                                     Error **errp)
  60 +{
  61 +    QString *raw_path;
  62 +
  63 +    /* Parse the blkverify: prefix */
  64 +    if (!strstart(filename, "zeroinit:", &filename)) {
  65 +        /* There was no prefix; therefore, all options have to be already
  66 +           present in the QDict (except for the filename) */
  67 +        return;
  68 +    }
  69 +
  70 +    raw_path = qstring_from_str(filename);
  71 +    qdict_put(options, "x-next", raw_path);
  72 +}
  73 +
  74 +static QemuOptsList runtime_opts = {
  75 +    .name = "zeroinit",
  76 +    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
  77 +    .desc = {
  78 +        {
  79 +            .name = "x-next",
  80 +            .type = QEMU_OPT_STRING,
  81 +            .help = "[internal use only, will be removed]",
  82 +        },
  83 +        {
  84 +            .name = "x-zeroinit",
  85 +            .type = QEMU_OPT_BOOL,
  86 +            .help = "set has_initialized_zero flag",
  87 +        },
  88 +        { /* end of list */ }
  89 +    },
  90 +};
  91 +
  92 +static int zeroinit_open(BlockDriverState *bs, QDict *options, int flags,
  93 +                          Error **errp)
  94 +{
  95 +    BDRVZeroinitState *s = bs->opaque;
  96 +    QemuOpts *opts;
  97 +    Error *local_err = NULL;
  98 +    int ret;
  99 +
 100 +    s->extents = 0;
 101 +
 102 +    opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 103 +    qemu_opts_absorb_qdict(opts, options, &local_err);
 104 +    if (local_err) {
 105 +        error_propagate(errp, local_err);
 106 +        ret = -EINVAL;
 107 +        goto fail;
 108 +    }
 109 +
 110 +    /* Open the raw file */
 111 +    bs->file = bdrv_open_child(qemu_opt_get(opts, "x-next"), options, "next",
 112 +                               bs, &child_of_bds, BDRV_CHILD_FILTERED, false, &local_err);
 113 +    if (local_err) {
 114 +        ret = -EINVAL;
 115 +        error_propagate(errp, local_err);
 116 +        goto fail;
 117 +    }
 118 +
 119 +    /* set the options */
 120 +    s->has_zero_init = qemu_opt_get_bool(opts, "x-zeroinit", true);
 121 +
 122 +    ret = 0;
 123 +fail:
 124 +    if (ret < 0) {
 125 +        bdrv_unref_child(bs, bs->file);
 126 +    }
 127 +    qemu_opts_del(opts);
 128 +    return ret;
 129 +}
 130 +
 131 +static void zeroinit_close(BlockDriverState *bs)
 132 +{
 133 +    BDRVZeroinitState *s = bs->opaque;
 134 +    (void)s;
 135 +}
 136 +
 137 +static int64_t zeroinit_getlength(BlockDriverState *bs)
 138 +{
 139 +    return bdrv_getlength(bs->file->bs);
 140 +}
 141 +
 142 +static int coroutine_fn zeroinit_co_preadv(BlockDriverState *bs,
 143 +    int64_t offset, int64_t bytes, QEMUIOVector *qiov, BdrvRequestFlags flags)
 144 +{
 145 +    return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
 146 +}
 147 +
 148 +static int coroutine_fn zeroinit_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
 149 +                                                 int64_t bytes, BdrvRequestFlags flags)
 150 +{
 151 +    BDRVZeroinitState *s = bs->opaque;
 152 +    if (offset >= s->extents)
 153 +        return 0;
 154 +    return bdrv_pwrite_zeroes(bs->file, offset, bytes, flags);
 155 +}
 156 +
 157 +static int coroutine_fn zeroinit_co_pwritev(BlockDriverState *bs,
 158 +    int64_t offset, int64_t bytes, QEMUIOVector *qiov, BdrvRequestFlags flags)
 159 +{
 160 +    BDRVZeroinitState *s = bs->opaque;
 161 +    int64_t extents = offset + bytes;
 162 +    if (extents > s->extents)
 163 +        s->extents = extents;
 164 +    return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
 165 +}
 166 +
 167 +static coroutine_fn int zeroinit_co_flush(BlockDriverState *bs)
 168 +{
 169 +    return bdrv_co_flush(bs->file->bs);
 170 +}
 171 +
 172 +static int zeroinit_has_zero_init(BlockDriverState *bs)
 173 +{
 174 +    BDRVZeroinitState *s = bs->opaque;
 175 +    return s->has_zero_init;
 176 +}
 177 +
 178 +static int coroutine_fn zeroinit_co_pdiscard(BlockDriverState *bs,
 179 +                                             int64_t offset, int64_t bytes)
 180 +{
 181 +    return bdrv_co_pdiscard(bs->file, offset, bytes);
 182 +}
 183 +
 184 +static int zeroinit_co_truncate(BlockDriverState *bs, int64_t offset,
 185 +                                _Bool exact, PreallocMode prealloc,
 186 +                                BdrvRequestFlags req_flags, Error **errp)
 187 +{
 188 +    return bdrv_co_truncate(bs->file, offset, exact, prealloc, req_flags, 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_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 +
 215 +    .bdrv_has_zero_init               = zeroinit_has_zero_init,
 216 +
 217 +    .bdrv_co_pdiscard                 = zeroinit_co_pdiscard,
 218 +
 219 +    .bdrv_co_truncate                 = zeroinit_co_truncate,
 220 +    .bdrv_get_info                    = zeroinit_get_info,
 221 +};
 222 +
 223 +static void bdrv_zeroinit_init(void)
 224 +{
 225 +    bdrv_register(&bdrv_zeroinit);
 226 +}
 227 +
 228 +block_init(bdrv_zeroinit_init);