#include "block/block_int.h"
#include "block/blockjob_int.h"
#include "qapi/error.h"
-#include "qapi/qmp/qerror.h"
#include "qapi/qmp/qdict.h"
#include "qemu/ratelimit.h"
#include "sysemu/block-backend.h"
static int stream_prepare(Job *job)
{
StreamBlockJob *s = container_of(job, StreamBlockJob, common.job);
- BlockDriverState *unfiltered_bs = bdrv_skip_filters(s->target_bs);
+ BlockDriverState *unfiltered_bs;
+ BlockDriverState *unfiltered_bs_cow;
BlockDriverState *base;
BlockDriverState *unfiltered_base;
Error *local_err = NULL;
int ret = 0;
+ GLOBAL_STATE_CODE();
+
+ bdrv_graph_rdlock_main_loop();
+ unfiltered_bs = bdrv_skip_filters(s->target_bs);
+ unfiltered_bs_cow = bdrv_cow_bs(unfiltered_bs);
+ bdrv_graph_rdunlock_main_loop();
+
/* We should drop filter at this point, as filter hold the backing chain */
bdrv_cor_filter_drop(s->cor_filter_bs);
s->cor_filter_bs = NULL;
- bdrv_subtree_drained_begin(s->above_base);
-
- base = bdrv_filter_or_cow_bs(s->above_base);
- if (base) {
- bdrv_ref(base);
+ /*
+ * bdrv_set_backing_hd() requires that the unfiltered_bs and the COW child
+ * of unfiltered_bs is drained. Drain already here and use
+ * bdrv_set_backing_hd_drained() instead because the polling during
+ * drained_begin() might change the graph, and if we do this only later, we
+ * may end up working with the wrong base node (or it might even have gone
+ * away by the time we want to use it).
+ */
+ bdrv_drained_begin(unfiltered_bs);
+ if (unfiltered_bs_cow) {
+ bdrv_ref(unfiltered_bs_cow);
+ bdrv_drained_begin(unfiltered_bs_cow);
}
+ bdrv_graph_rdlock_main_loop();
+ base = bdrv_filter_or_cow_bs(s->above_base);
unfiltered_base = bdrv_skip_filters(base);
+ bdrv_graph_rdunlock_main_loop();
- if (bdrv_cow_child(unfiltered_bs)) {
+ if (unfiltered_bs_cow) {
const char *base_id = NULL, *base_fmt = NULL;
if (unfiltered_base) {
base_id = s->backing_file_str ?: unfiltered_base->filename;
}
}
- bdrv_set_backing_hd(unfiltered_bs, base, &local_err);
+ bdrv_graph_wrlock(s->target_bs);
+ bdrv_set_backing_hd_drained(unfiltered_bs, base, &local_err);
+ bdrv_graph_wrunlock(s->target_bs);
+
+ /*
+ * This call will do I/O, so the graph can change again from here on.
+ * We have already completed the graph change, so we are not in danger
+ * of operating on the wrong node any more if this happens.
+ */
ret = bdrv_change_backing_file(unfiltered_bs, base_id, base_fmt, false);
if (local_err) {
error_report_err(local_err);
}
out:
- if (base) {
- bdrv_unref(base);
+ if (unfiltered_bs_cow) {
+ bdrv_drained_end(unfiltered_bs_cow);
+ bdrv_unref(unfiltered_bs_cow);
}
- bdrv_subtree_drained_end(s->above_base);
+ bdrv_drained_end(unfiltered_bs);
return ret;
}
static int coroutine_fn stream_run(Job *job, Error **errp)
{
StreamBlockJob *s = container_of(job, StreamBlockJob, common.job);
- BlockDriverState *unfiltered_bs = bdrv_skip_filters(s->target_bs);
+ BlockDriverState *unfiltered_bs;
int64_t len;
int64_t offset = 0;
- uint64_t delay_ns = 0;
int error = 0;
int64_t n = 0; /* bytes */
- if (unfiltered_bs == s->base_overlay) {
- /* Nothing to stream */
- return 0;
- }
+ WITH_GRAPH_RDLOCK_GUARD() {
+ unfiltered_bs = bdrv_skip_filters(s->target_bs);
+ if (unfiltered_bs == s->base_overlay) {
+ /* Nothing to stream */
+ return 0;
+ }
- len = bdrv_getlength(s->target_bs);
- if (len < 0) {
- return len;
+ len = bdrv_co_getlength(s->target_bs);
+ if (len < 0) {
+ return len;
+ }
}
job_progress_set_remaining(&s->common.job, len);
/* Note that even when no rate limit is applied we need to yield
* with no pending I/O here so that bdrv_drain_all() returns.
*/
- job_sleep_ns(&s->common.job, delay_ns);
+ block_job_ratelimit_sleep(&s->common);
if (job_is_cancelled(&s->common.job)) {
break;
}
copy = false;
- ret = bdrv_is_allocated(unfiltered_bs, offset, STREAM_CHUNK, &n);
- if (ret == 1) {
- /* Allocated in the top, no need to copy. */
- } else if (ret >= 0) {
- /* Copy if allocated in the intermediate images. Limit to the
- * known-unallocated area [offset, offset+n*BDRV_SECTOR_SIZE). */
- ret = bdrv_is_allocated_above(bdrv_cow_bs(unfiltered_bs),
- s->base_overlay, true,
- offset, n, &n);
- /* Finish early if end of backing file has been reached */
- if (ret == 0 && n == 0) {
- n = len - offset;
+ WITH_GRAPH_RDLOCK_GUARD() {
+ ret = bdrv_co_is_allocated(unfiltered_bs, offset, STREAM_CHUNK, &n);
+ if (ret == 1) {
+ /* Allocated in the top, no need to copy. */
+ } else if (ret >= 0) {
+ /*
+ * Copy if allocated in the intermediate images. Limit to the
+ * known-unallocated area [offset, offset+n*BDRV_SECTOR_SIZE).
+ */
+ ret = bdrv_co_is_allocated_above(bdrv_cow_bs(unfiltered_bs),
+ s->base_overlay, true,
+ offset, n, &n);
+ /* Finish early if end of backing file has been reached */
+ if (ret == 0 && n == 0) {
+ n = len - offset;
+ }
+
+ copy = (ret > 0);
}
-
- copy = (ret > 0);
}
trace_stream_one_iteration(s, offset, n, ret);
if (copy) {
/* Publish progress */
job_progress_update(&s->common.job, n);
if (copy) {
- delay_ns = block_job_ratelimit_get_delay(&s->common, n);
- } else {
- delay_ns = 0;
+ block_job_ratelimit_processed_bytes(&s->common, n);
}
}
assert(!(base && bottom));
assert(!(backing_file_str && bottom));
+ bdrv_graph_rdlock_main_loop();
+
if (bottom) {
/*
* New simple interface. The code is written in terms of old interface
if (!base_overlay) {
error_setg(errp, "'%s' is not in the backing chain of '%s'",
base->node_name, bs->node_name);
- return;
+ goto out_rdlock;
}
/*
/* Make sure that the image is opened in read-write mode */
bs_read_only = bdrv_is_read_only(bs);
if (bs_read_only) {
- int ret;
/* Hold the chain during reopen */
if (bdrv_freeze_backing_chain(bs, above_base, errp) < 0) {
- return;
+ goto out_rdlock;
}
ret = bdrv_reopen_set_read_only(bs, false, errp);
bdrv_unfreeze_backing_chain(bs, above_base);
if (ret < 0) {
- return;
+ goto out_rdlock;
}
}
+ bdrv_graph_rdunlock_main_loop();
+
opts = qdict_new();
qdict_put_str(opts, "driver", "copy-on-read");
* already have our own plans. Also don't allow resize as the image size is
* queried only at the job start and then cached.
*/
+ bdrv_graph_wrlock(bs);
if (block_job_add_bdrv(&s->common, "active node", bs, 0,
basic_flags | BLK_PERM_WRITE, errp)) {
+ bdrv_graph_wrunlock(bs);
goto fail;
}
ret = block_job_add_bdrv(&s->common, "intermediate node", iter, 0,
basic_flags, errp);
if (ret < 0) {
+ bdrv_graph_wrunlock(bs);
goto fail;
}
}
+ bdrv_graph_wrunlock(bs);
s->base_overlay = base_overlay;
s->above_base = above_base;
if (bs_read_only) {
bdrv_reopen_set_read_only(bs, true, NULL);
}
+ return;
+
+out_rdlock:
+ bdrv_graph_rdunlock_main_loop();
}