debian/patches/pve/0033-block-add-the-zeroinit-block-driver-filter.patch

   1 From 35facc3a3549baf4cccaef27afa9c35a25abe91c 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 33/47] block: add the zeroinit block driver filter
   5
   6 ---
   7  block/Makefile.objs |   1 +
   8  block/zeroinit.c    | 219 ++++++++++++++++++++++++++++++++++++++++++++++++++++
   9  2 files changed, 220 insertions(+)
  10  create mode 100644 block/zeroinit.c
  11
  12 diff --git a/block/Makefile.objs b/block/Makefile.objs
  13 index de96f8e..8cdac08 100644
  14 --- a/block/Makefile.objs
  15 +++ b/block/Makefile.objs
  16 @@ -4,6 +4,7 @@ block-obj-y += qed.o qed-gencb.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 0000000..0a8c7f9
  27 --- /dev/null
  28 +++ b/block/zeroinit.c
  29 @@ -0,0 +1,219 @@
  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 BlockAIOCB *zeroinit_aio_readv(BlockDriverState *bs,
 138 +        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 139 +        BlockCompletionFunc *cb, void *opaque)
 140 +{
 141 +    return bdrv_aio_readv(bs->file, sector_num, qiov, nb_sectors,
 142 +                          cb, opaque);
 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 BlockAIOCB *zeroinit_aio_writev(BlockDriverState *bs,
 155 +        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 156 +        BlockCompletionFunc *cb, void *opaque)
 157 +{
 158 +    BDRVZeroinitState *s = bs->opaque;
 159 +    int64_t extents = (sector_num << BDRV_SECTOR_BITS) + ((nb_sectors + 1) << BDRV_SECTOR_BITS);
 160 +    if (extents > s->extents)
 161 +        s->extents = extents;
 162 +    return bdrv_aio_writev(bs->file, sector_num, qiov, nb_sectors,
 163 +                           cb, opaque);
 164 +}
 165 +
 166 +static BlockAIOCB *zeroinit_aio_flush(BlockDriverState *bs,
 167 +                                       BlockCompletionFunc *cb,
 168 +                                       void *opaque)
 169 +{
 170 +    return bdrv_aio_flush(bs->file->bs, cb, opaque);
 171 +}
 172 +
 173 +static bool zeroinit_recurse_is_first_non_filter(BlockDriverState *bs,
 174 +                                                  BlockDriverState *candidate)
 175 +{
 176 +    return bdrv_recurse_is_first_non_filter(bs->file->bs, candidate);
 177 +}
 178 +
 179 +static coroutine_fn int zeroinit_co_flush(BlockDriverState *bs)
 180 +{
 181 +    return bdrv_co_flush(bs->file->bs);
 182 +}
 183 +
 184 +static int zeroinit_has_zero_init(BlockDriverState *bs)
 185 +{
 186 +    BDRVZeroinitState *s = bs->opaque;
 187 +    return s->has_zero_init;
 188 +}
 189 +
 190 +static int64_t coroutine_fn zeroinit_co_get_block_status(BlockDriverState *bs,
 191 +                                                         int64_t sector_num,
 192 +                                                         int nb_sectors, int *pnum,
 193 +                                                         BlockDriverState **file)
 194 +{
 195 +    return bdrv_get_block_status(bs->file->bs, sector_num, nb_sectors, pnum, file);
 196 +}
 197 +
 198 +static int coroutine_fn zeroinit_co_pdiscard(BlockDriverState *bs,
 199 +                                             int64_t offset, int count)
 200 +{
 201 +    return bdrv_co_pdiscard(bs->file->bs, offset, count);
 202 +}
 203 +
 204 +static int zeroinit_truncate(BlockDriverState *bs, int64_t offset)
 205 +{
 206 +    return bdrv_truncate(bs->file, offset);
 207 +}
 208 +
 209 +static int zeroinit_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
 210 +{
 211 +    return bdrv_get_info(bs->file->bs, bdi);
 212 +}
 213 +
 214 +static BlockDriver bdrv_zeroinit = {
 215 +    .format_name                      = "zeroinit",
 216 +    .protocol_name                    = "zeroinit",
 217 +    .instance_size                    = sizeof(BDRVZeroinitState),
 218 +
 219 +    .bdrv_parse_filename              = zeroinit_parse_filename,
 220 +    .bdrv_file_open                   = zeroinit_open,
 221 +    .bdrv_close                       = zeroinit_close,
 222 +    .bdrv_getlength                   = zeroinit_getlength,
 223 +    .bdrv_co_flush_to_disk            = zeroinit_co_flush,
 224 +
 225 +    .bdrv_co_pwrite_zeroes            = zeroinit_co_pwrite_zeroes,
 226 +    .bdrv_aio_writev                  = zeroinit_aio_writev,
 227 +    .bdrv_aio_readv                   = zeroinit_aio_readv,
 228 +    .bdrv_aio_flush                   = zeroinit_aio_flush,
 229 +
 230 +    .is_filter                        = true,
 231 +    .bdrv_recurse_is_first_non_filter = zeroinit_recurse_is_first_non_filter,
 232 +
 233 +    .bdrv_has_zero_init = zeroinit_has_zero_init,
 234 +
 235 +    .bdrv_co_get_block_status = zeroinit_co_get_block_status,
 236 +
 237 +    .bdrv_co_pdiscard = zeroinit_co_pdiscard,
 238 +
 239 +    .bdrv_truncate = zeroinit_truncate,
 240 +    .bdrv_get_info = zeroinit_get_info,
 241 +};
 242 +
 243 +static void bdrv_zeroinit_init(void)
 244 +{
 245 +    bdrv_register(&bdrv_zeroinit);
 246 +}
 247 +
 248 +block_init(bdrv_zeroinit_init);
 249 --
 250 2.1.4
 251