void commit_start(BlockDriverState *bs, BlockDriverState *base,
BlockDriverState *top, int64_t speed,
BlockErrorAction on_error, BlockDriverCompletionFunc *cb,
void *opaque, Error **errp)
{
CommitBlockJob *s;
BlockReopenQueue *reopen_queue = NULL;
int orig_overlay_flags;
int orig_base_flags;
BlockDriverState *overlay_bs;
Error *local_err = NULL;
if ((on_error == BLOCK_ERR_STOP_ANY ||
on_error == BLOCK_ERR_STOP_ENOSPC) &&
!bdrv_iostatus_is_enabled(bs)) {
error_set(errp, QERR_INVALID_PARAMETER_COMBINATION);
return;
}
/* Once we support top == active layer, remove this check */
if (top == bs) {
error_set(errp, QERR_TOP_IS_ACTIVE);
return;
}
if (top == base) {
error_set(errp, QERR_TOP_AND_BASE_IDENTICAL);
return;
}
overlay_bs = bdrv_find_overlay(bs, top);
if (overlay_bs == NULL) {
error_set(errp, QERR_TOP_NOT_FOUND, top->filename);
return;
}
orig_base_flags = bdrv_get_flags(base);
orig_overlay_flags = bdrv_get_flags(overlay_bs);
/* convert base & overlay_bs to r/w, if necessary */
if (!(orig_base_flags & BDRV_O_RDWR)) {
reopen_queue = bdrv_reopen_queue(reopen_queue, base,
orig_base_flags | BDRV_O_RDWR);
}
if (!(orig_overlay_flags & BDRV_O_RDWR)) {
reopen_queue = bdrv_reopen_queue(reopen_queue, overlay_bs,
orig_overlay_flags | BDRV_O_RDWR);
}
if (reopen_queue) {
bdrv_reopen_multiple(reopen_queue, &local_err);
if (local_err != NULL) {
error_propagate(errp, local_err);
return;
}
}
s = block_job_create(&commit_job_type, bs, speed, cb, opaque);
if (!s) {
error_set(errp, QERR_DEVICE_IN_USE, bs->device_name);
return;
}
s->base = base;
s->top = top;
s->active = bs;
s->base_flags = orig_base_flags;
s->orig_overlay_flags = orig_overlay_flags;
s->on_error = on_error;
s->common.co = qemu_coroutine_create(commit_run);
trace_commit_start(bs, base, top, s, s->common.co, opaque);
qemu_coroutine_enter(s->common.co, s);
}
void commit_start(const char *job_id, BlockDriverState *bs,
BlockDriverState *base, BlockDriverState *top,
int creation_flags, int64_t speed,
BlockdevOnError on_error, const char *backing_file_str,
const char *filter_node_name, Error **errp)
{
CommitBlockJob *s;
BlockDriverState *iter;
BlockDriverState *commit_top_bs = NULL;
Error *local_err = NULL;
int ret;
assert(top != bs);
if (top == base) {
error_setg(errp, "Invalid files for merge: top and base are the same");
return;
}
s = block_job_create(job_id, &commit_job_driver, NULL, bs, 0, BLK_PERM_ALL,
speed, creation_flags, NULL, NULL, errp);
if (!s) {
return;
}
/* convert base to r/w, if necessary */
s->base_read_only = bdrv_is_read_only(base);
if (s->base_read_only) {
if (bdrv_reopen_set_read_only(base, false, errp) != 0) {
goto fail;
}
}
/* Insert commit_top block node above top, so we can block consistent read
* on the backing chain below it */
commit_top_bs = bdrv_new_open_driver(&bdrv_commit_top, filter_node_name, 0,
errp);
if (commit_top_bs == NULL) {
goto fail;
}
if (!filter_node_name) {
commit_top_bs->implicit = true;
}
commit_top_bs->total_sectors = top->total_sectors;
bdrv_set_aio_context(commit_top_bs, bdrv_get_aio_context(top));
bdrv_set_backing_hd(commit_top_bs, top, &local_err);
if (local_err) {
bdrv_unref(commit_top_bs);
commit_top_bs = NULL;
error_propagate(errp, local_err);
goto fail;
}
bdrv_replace_node(top, commit_top_bs, &local_err);
if (local_err) {
bdrv_unref(commit_top_bs);
commit_top_bs = NULL;
error_propagate(errp, local_err);
goto fail;
}
s->commit_top_bs = commit_top_bs;
bdrv_unref(commit_top_bs);
/* Block all nodes between top and base, because they will
* disappear from the chain after this operation. */
assert(bdrv_chain_contains(top, base));
for (iter = top; iter != base; iter = backing_bs(iter)) {
/* XXX BLK_PERM_WRITE needs to be allowed so we don't block ourselves
* at s->base (if writes are blocked for a node, they are also blocked
* for its backing file). The other options would be a second filter
* driver above s->base. */
ret = block_job_add_bdrv(&s->common, "intermediate node", iter, 0,
BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE,
errp);
if (ret < 0) {
goto fail;
}
}
if (bdrv_freeze_backing_chain(commit_top_bs, base, errp) < 0) {
goto fail;
}
s->chain_frozen = true;
ret = block_job_add_bdrv(&s->common, "base", base, 0, BLK_PERM_ALL, errp);
if (ret < 0) {
goto fail;
}
s->base = blk_new(BLK_PERM_CONSISTENT_READ
| BLK_PERM_WRITE
| BLK_PERM_RESIZE,
BLK_PERM_CONSISTENT_READ
| BLK_PERM_GRAPH_MOD
| BLK_PERM_WRITE_UNCHANGED);
ret = blk_insert_bs(s->base, base, errp);
if (ret < 0) {
goto fail;
}
s->base_bs = base;
/* Required permissions are already taken with block_job_add_bdrv() */
s->top = blk_new(0, BLK_PERM_ALL);
ret = blk_insert_bs(s->top, top, errp);
if (ret < 0) {
goto fail;
}
s->backing_file_str = g_strdup(backing_file_str);
s->on_error = on_error;
trace_commit_start(bs, base, top, s);
job_start(&s->common.job);
return;
fail:
if (s->chain_frozen) {
bdrv_unfreeze_backing_chain(commit_top_bs, base);
}
if (s->base) {
blk_unref(s->base);
}
if (s->top) {
blk_unref(s->top);
}
job_early_fail(&s->common.job);
/* commit_top_bs has to be replaced after deleting the block job,
* otherwise this would fail because of lack of permissions. */
if (commit_top_bs) {
bdrv_replace_node(commit_top_bs, top, &error_abort);
}
}
void commit_start(BlockDriverState *bs, BlockDriverState *base,
BlockDriverState *top, int64_t speed,
BlockdevOnError on_error, BlockDriverCompletionFunc *cb,
void *opaque, Error **errp)
{
CommitBlockJob *s;
BlockReopenQueue *reopen_queue = NULL;
int orig_overlay_flags;
int orig_base_flags;
BlockDriverState *overlay_bs;
Error *local_err = NULL;
if ((on_error == BLOCKDEV_ON_ERROR_STOP ||
on_error == BLOCKDEV_ON_ERROR_ENOSPC) &&
!bdrv_iostatus_is_enabled(bs)) {
error_set(errp, QERR_INVALID_PARAMETER_COMBINATION);
return;
}
/* Once we support top == active layer, remove this check */
if (top == bs) {
error_setg(errp,
"Top image as the active layer is currently unsupported");
return;
}
if (top == base) {
error_setg(errp, "Invalid files for merge: top and base are the same");
return;
}
overlay_bs = bdrv_find_overlay(bs, top);
if (overlay_bs == NULL) {
error_setg(errp, "Could not find overlay image for %s:", top->filename);
return;
}
orig_base_flags = bdrv_get_flags(base);
orig_overlay_flags = bdrv_get_flags(overlay_bs);
/* convert base & overlay_bs to r/w, if necessary */
if (!(orig_base_flags & BDRV_O_RDWR)) {
reopen_queue = bdrv_reopen_queue(reopen_queue, base,
orig_base_flags | BDRV_O_RDWR);
}
if (!(orig_overlay_flags & BDRV_O_RDWR)) {
reopen_queue = bdrv_reopen_queue(reopen_queue, overlay_bs,
orig_overlay_flags | BDRV_O_RDWR);
}
if (reopen_queue) {
bdrv_reopen_multiple(reopen_queue, &local_err);
if (local_err != NULL) {
error_propagate(errp, local_err);
return;
}
}
s = block_job_create(&commit_job_type, bs, speed, cb, opaque, errp);
if (!s) {
return;
}
s->base = base;
s->top = top;
s->active = bs;
s->base_flags = orig_base_flags;
s->orig_overlay_flags = orig_overlay_flags;
s->on_error = on_error;
s->common.co = qemu_coroutine_create(commit_run);
trace_commit_start(bs, base, top, s, s->common.co, opaque);
qemu_coroutine_enter(s->common.co, s);
}
