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-rw-r--r--block/backup-top.c253
1 files changed, 0 insertions, 253 deletions
diff --git a/block/backup-top.c b/block/backup-top.c
deleted file mode 100644
index 425e3778be..0000000000
--- a/block/backup-top.c
+++ /dev/null
@@ -1,253 +0,0 @@
-/*
- * backup-top filter driver
- *
- * The driver performs Copy-Before-Write (CBW) operation: it is injected above
- * some node, and before each write it copies _old_ data to the target node.
- *
- * Copyright (c) 2018-2019 Virtuozzo International GmbH.
- *
- * Author:
- * Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
- *
- * 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 of the License, or
- * (at your option) any later version.
- *
- * 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 "sysemu/block-backend.h"
-#include "qemu/cutils.h"
-#include "qapi/error.h"
-#include "block/block_int.h"
-#include "block/qdict.h"
-#include "block/block-copy.h"
-
-#include "block/backup-top.h"
-
-typedef struct BDRVBackupTopState {
- BlockCopyState *bcs;
- BdrvChild *target;
- int64_t cluster_size;
-} BDRVBackupTopState;
-
-static coroutine_fn int backup_top_co_preadv(
- BlockDriverState *bs, uint64_t offset, uint64_t bytes,
- QEMUIOVector *qiov, int flags)
-{
- return bdrv_co_preadv(bs->backing, offset, bytes, qiov, flags);
-}
-
-static coroutine_fn int backup_top_cbw(BlockDriverState *bs, uint64_t offset,
- uint64_t bytes, BdrvRequestFlags flags)
-{
- BDRVBackupTopState *s = bs->opaque;
- uint64_t off, end;
-
- if (flags & BDRV_REQ_WRITE_UNCHANGED) {
- return 0;
- }
-
- off = QEMU_ALIGN_DOWN(offset, s->cluster_size);
- end = QEMU_ALIGN_UP(offset + bytes, s->cluster_size);
-
- return block_copy(s->bcs, off, end - off, true);
-}
-
-static int coroutine_fn backup_top_co_pdiscard(BlockDriverState *bs,
- int64_t offset, int bytes)
-{
- int ret = backup_top_cbw(bs, offset, bytes, 0);
- if (ret < 0) {
- return ret;
- }
-
- return bdrv_co_pdiscard(bs->backing, offset, bytes);
-}
-
-static int coroutine_fn backup_top_co_pwrite_zeroes(BlockDriverState *bs,
- int64_t offset, int bytes, BdrvRequestFlags flags)
-{
- int ret = backup_top_cbw(bs, offset, bytes, flags);
- if (ret < 0) {
- return ret;
- }
-
- return bdrv_co_pwrite_zeroes(bs->backing, offset, bytes, flags);
-}
-
-static coroutine_fn int backup_top_co_pwritev(BlockDriverState *bs,
- uint64_t offset,
- uint64_t bytes,
- QEMUIOVector *qiov, int flags)
-{
- int ret = backup_top_cbw(bs, offset, bytes, flags);
- if (ret < 0) {
- return ret;
- }
-
- return bdrv_co_pwritev(bs->backing, offset, bytes, qiov, flags);
-}
-
-static int coroutine_fn backup_top_co_flush(BlockDriverState *bs)
-{
- if (!bs->backing) {
- return 0;
- }
-
- return bdrv_co_flush(bs->backing->bs);
-}
-
-static void backup_top_refresh_filename(BlockDriverState *bs)
-{
- if (bs->backing == NULL) {
- /*
- * we can be here after failed bdrv_attach_child in
- * bdrv_set_backing_hd
- */
- return;
- }
- pstrcpy(bs->exact_filename, sizeof(bs->exact_filename),
- bs->backing->bs->filename);
-}
-
-static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c,
- BdrvChildRole role,
- BlockReopenQueue *reopen_queue,
- uint64_t perm, uint64_t shared,
- uint64_t *nperm, uint64_t *nshared)
-{
- if (!(role & BDRV_CHILD_FILTERED)) {
- /*
- * Target child
- *
- * Share write to target (child_file), to not interfere
- * with guest writes to its disk which may be in target backing chain.
- * Can't resize during a backup block job because we check the size
- * only upfront.
- */
- *nshared = BLK_PERM_ALL & ~BLK_PERM_RESIZE;
- *nperm = BLK_PERM_WRITE;
- } else {
- /* Source child */
- bdrv_default_perms(bs, c, role, reopen_queue,
- perm, shared, nperm, nshared);
-
- if (perm & BLK_PERM_WRITE) {
- *nperm = *nperm | BLK_PERM_CONSISTENT_READ;
- }
- *nshared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE);
- }
-}
-
-BlockDriver bdrv_backup_top_filter = {
- .format_name = "backup-top",
- .instance_size = sizeof(BDRVBackupTopState),
-
- .bdrv_co_preadv = backup_top_co_preadv,
- .bdrv_co_pwritev = backup_top_co_pwritev,
- .bdrv_co_pwrite_zeroes = backup_top_co_pwrite_zeroes,
- .bdrv_co_pdiscard = backup_top_co_pdiscard,
- .bdrv_co_flush = backup_top_co_flush,
-
- .bdrv_refresh_filename = backup_top_refresh_filename,
-
- .bdrv_child_perm = backup_top_child_perm,
-
- .is_filter = true,
-};
-
-BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
- BlockDriverState *target,
- const char *filter_node_name,
- uint64_t cluster_size,
- BackupPerf *perf,
- BdrvRequestFlags write_flags,
- BlockCopyState **bcs,
- Error **errp)
-{
- ERRP_GUARD();
- int ret;
- BDRVBackupTopState *state;
- BlockDriverState *top;
- bool appended = false;
-
- assert(source->total_sectors == target->total_sectors);
-
- top = bdrv_new_open_driver(&bdrv_backup_top_filter, filter_node_name,
- BDRV_O_RDWR, errp);
- if (!top) {
- return NULL;
- }
-
- state = top->opaque;
- top->total_sectors = source->total_sectors;
- top->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
- (BDRV_REQ_FUA & source->supported_write_flags);
- top->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
- ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
- source->supported_zero_flags);
-
- bdrv_ref(target);
- state->target = bdrv_attach_child(top, target, "target", &child_of_bds,
- BDRV_CHILD_DATA, errp);
- if (!state->target) {
- bdrv_unref(target);
- bdrv_unref(top);
- return NULL;
- }
-
- bdrv_drained_begin(source);
-
- ret = bdrv_append(top, source, errp);
- if (ret < 0) {
- error_prepend(errp, "Cannot append backup-top filter: ");
- goto fail;
- }
- appended = true;
-
- state->cluster_size = cluster_size;
- state->bcs = block_copy_state_new(top->backing, state->target,
- cluster_size, perf->use_copy_range,
- write_flags, errp);
- if (!state->bcs) {
- error_prepend(errp, "Cannot create block-copy-state: ");
- goto fail;
- }
- *bcs = state->bcs;
-
- bdrv_drained_end(source);
-
- return top;
-
-fail:
- if (appended) {
- bdrv_backup_top_drop(top);
- } else {
- bdrv_unref(top);
- }
-
- bdrv_drained_end(source);
-
- return NULL;
-}
-
-void bdrv_backup_top_drop(BlockDriverState *bs)
-{
- BDRVBackupTopState *s = bs->opaque;
-
- bdrv_drop_filter(bs, &error_abort);
-
- block_copy_state_free(s->bcs);
-
- bdrv_unref(bs);
-}