diff options
| -rw-r--r-- | block/Makefile.objs | 1 | ||||
| -rw-r--r-- | block/filter-compress.c | 168 | ||||
| -rw-r--r-- | qapi/block-core.json | 10 |
3 files changed, 175 insertions, 4 deletions
diff --git a/block/Makefile.objs b/block/Makefile.objs index e394fe0..330529b 100644 --- a/block/Makefile.objs +++ b/block/Makefile.objs @@ -43,6 +43,7 @@ block-obj-y += crypto.o block-obj-y += aio_task.o block-obj-y += backup-top.o +block-obj-y += filter-compress.o common-obj-y += stream.o diff --git a/block/filter-compress.c b/block/filter-compress.c new file mode 100644 index 0000000..60137fb --- /dev/null +++ b/block/filter-compress.c @@ -0,0 +1,168 @@ +/* + * Compress filter block driver + * + * Copyright (c) 2019 Virtuozzo International GmbH + * + * Author: + * Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> + * (based on block/copy-on-read.c by Max Reitz) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 or + * (at your option) any later version of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#include "qemu/osdep.h" +#include "block/block_int.h" +#include "qemu/module.h" +#include "qapi/error.h" + + +static int compress_open(BlockDriverState *bs, QDict *options, int flags, + Error **errp) +{ + bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, false, + errp); + if (!bs->file) { + return -EINVAL; + } + + if (!bs->file->bs->drv || !block_driver_can_compress(bs->file->bs->drv)) { + error_setg(errp, + "Compression is not supported for underlying format: %s", + bdrv_get_format_name(bs->file->bs) ?: "(no format)"); + + return -ENOTSUP; + } + + bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED | + (BDRV_REQ_FUA & bs->file->bs->supported_write_flags); + + bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED | + ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) & + bs->file->bs->supported_zero_flags); + + return 0; +} + + +static int64_t compress_getlength(BlockDriverState *bs) +{ + return bdrv_getlength(bs->file->bs); +} + + +static int coroutine_fn compress_co_preadv_part(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, + size_t qiov_offset, + int flags) +{ + return bdrv_co_preadv_part(bs->file, offset, bytes, qiov, qiov_offset, + flags); +} + + +static int coroutine_fn compress_co_pwritev_part(BlockDriverState *bs, + uint64_t offset, + uint64_t bytes, + QEMUIOVector *qiov, + size_t qiov_offset, int flags) +{ + return bdrv_co_pwritev_part(bs->file, offset, bytes, qiov, qiov_offset, + flags | BDRV_REQ_WRITE_COMPRESSED); +} + + +static int coroutine_fn compress_co_pwrite_zeroes(BlockDriverState *bs, + int64_t offset, int bytes, + BdrvRequestFlags flags) +{ + return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags); +} + + +static int coroutine_fn compress_co_pdiscard(BlockDriverState *bs, + int64_t offset, int bytes) +{ + return bdrv_co_pdiscard(bs->file, offset, bytes); +} + + +static void compress_refresh_limits(BlockDriverState *bs, Error **errp) +{ + BlockDriverInfo bdi; + int ret; + + if (!bs->file) { + return; + } + + ret = bdrv_get_info(bs->file->bs, &bdi); + if (ret < 0 || bdi.cluster_size == 0) { + return; + } + + bs->bl.request_alignment = bdi.cluster_size; +} + + +static void compress_eject(BlockDriverState *bs, bool eject_flag) +{ + bdrv_eject(bs->file->bs, eject_flag); +} + + +static void compress_lock_medium(BlockDriverState *bs, bool locked) +{ + bdrv_lock_medium(bs->file->bs, locked); +} + + +static bool compress_recurse_is_first_non_filter(BlockDriverState *bs, + BlockDriverState *candidate) +{ + return bdrv_recurse_is_first_non_filter(bs->file->bs, candidate); +} + + +static BlockDriver bdrv_compress = { + .format_name = "compress", + + .bdrv_open = compress_open, + .bdrv_child_perm = bdrv_filter_default_perms, + + .bdrv_getlength = compress_getlength, + + .bdrv_co_preadv_part = compress_co_preadv_part, + .bdrv_co_pwritev_part = compress_co_pwritev_part, + .bdrv_co_pwrite_zeroes = compress_co_pwrite_zeroes, + .bdrv_co_pdiscard = compress_co_pdiscard, + .bdrv_refresh_limits = compress_refresh_limits, + + .bdrv_eject = compress_eject, + .bdrv_lock_medium = compress_lock_medium, + + .bdrv_co_block_status = bdrv_co_block_status_from_file, + + .bdrv_recurse_is_first_non_filter = compress_recurse_is_first_non_filter, + + .has_variable_length = true, + .is_filter = true, +}; + +static void bdrv_compress_init(void) +{ + bdrv_register(&bdrv_compress); +} + +block_init(bdrv_compress_init); diff --git a/qapi/block-core.json b/qapi/block-core.json index 839b10b..7ff5e5e 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -2884,15 +2884,16 @@ # @copy-on-read: Since 3.0 # @blklogwrites: Since 3.0 # @blkreplay: Since 4.2 +# @compress: Since 5.0 # # Since: 2.9 ## { 'enum': 'BlockdevDriver', 'data': [ 'blkdebug', 'blklogwrites', 'blkreplay', 'blkverify', 'bochs', - 'cloop', 'copy-on-read', 'dmg', 'file', 'ftp', 'ftps', 'gluster', - 'host_cdrom', 'host_device', 'http', 'https', 'iscsi', 'luks', - 'nbd', 'nfs', 'null-aio', 'null-co', 'nvme', 'parallels', 'qcow', - 'qcow2', 'qed', 'quorum', 'raw', 'rbd', + 'cloop', 'compress', 'copy-on-read', 'dmg', 'file', 'ftp', 'ftps', + 'gluster', 'host_cdrom', 'host_device', 'http', 'https', 'iscsi', + 'luks', 'nbd', 'nfs', 'null-aio', 'null-co', 'nvme', 'parallels', + 'qcow', 'qcow2', 'qed', 'quorum', 'raw', 'rbd', { 'name': 'replication', 'if': 'defined(CONFIG_REPLICATION)' }, 'sheepdog', 'ssh', 'throttle', 'vdi', 'vhdx', 'vmdk', 'vpc', 'vvfat', 'vxhs' ] } @@ -4060,6 +4061,7 @@ 'blkreplay': 'BlockdevOptionsBlkreplay', 'bochs': 'BlockdevOptionsGenericFormat', 'cloop': 'BlockdevOptionsGenericFormat', + 'compress': 'BlockdevOptionsGenericFormat', 'copy-on-read':'BlockdevOptionsGenericFormat', 'dmg': 'BlockdevOptionsGenericFormat', 'file': 'BlockdevOptionsFile', |