From: Max Reitz <mreitz@redhat.com>
To: qemu-block@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>,
Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>,
qemu-devel@nongnu.org, Max Reitz <mreitz@redhat.com>
Subject: [PATCH v7 35/47] commit: Deal with filters
Date: Thu, 25 Jun 2020 17:22:03 +0200 [thread overview]
Message-ID: <20200625152215.941773-36-mreitz@redhat.com> (raw)
In-Reply-To: <20200625152215.941773-1-mreitz@redhat.com>
This includes some permission limiting (for example, we only need to
take the RESIZE permission if the base is smaller than the top).
Signed-off-by: Max Reitz <mreitz@redhat.com>
---
block/block-backend.c | 9 +++-
block/commit.c | 96 +++++++++++++++++++++++++---------
block/monitor/block-hmp-cmds.c | 2 +-
blockdev.c | 4 +-
4 files changed, 81 insertions(+), 30 deletions(-)
diff --git a/block/block-backend.c b/block/block-backend.c
index 6936b25c83..7f2c7dbccc 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -2271,8 +2271,13 @@ int blk_commit_all(void)
AioContext *aio_context = blk_get_aio_context(blk);
aio_context_acquire(aio_context);
- if (blk_is_inserted(blk) && blk->root->bs->backing) {
- int ret = bdrv_commit(blk->root->bs);
+ if (blk_is_inserted(blk)) {
+ BlockDriverState *non_filter;
+ int ret;
+
+ /* Legacy function, so skip implicit filters */
+ non_filter = bdrv_skip_implicit_filters(blk->root->bs);
+ ret = bdrv_commit(non_filter);
if (ret < 0) {
aio_context_release(aio_context);
return ret;
diff --git a/block/commit.c b/block/commit.c
index 7732d02dfe..4122b6736d 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -37,6 +37,7 @@ typedef struct CommitBlockJob {
BlockBackend *top;
BlockBackend *base;
BlockDriverState *base_bs;
+ BlockDriverState *base_overlay;
BlockdevOnError on_error;
bool base_read_only;
bool chain_frozen;
@@ -89,7 +90,7 @@ static void commit_abort(Job *job)
* XXX Can (or should) we somehow keep 'consistent read' blocked even
* after the failed/cancelled commit job is gone? If we already wrote
* something to base, the intermediate images aren't valid any more. */
- bdrv_replace_node(s->commit_top_bs, backing_bs(s->commit_top_bs),
+ bdrv_replace_node(s->commit_top_bs, s->commit_top_bs->backing->bs,
&error_abort);
bdrv_unref(s->commit_top_bs);
@@ -153,7 +154,7 @@ static int coroutine_fn commit_run(Job *job, Error **errp)
break;
}
/* Copy if allocated above the base */
- ret = bdrv_is_allocated_above(blk_bs(s->top), blk_bs(s->base), false,
+ ret = bdrv_is_allocated_above(blk_bs(s->top), s->base_overlay, true,
offset, COMMIT_BUFFER_SIZE, &n);
copy = (ret == 1);
trace_commit_one_iteration(s, offset, n, ret);
@@ -253,15 +254,35 @@ void commit_start(const char *job_id, BlockDriverState *bs,
CommitBlockJob *s;
BlockDriverState *iter;
BlockDriverState *commit_top_bs = NULL;
+ BlockDriverState *filtered_base;
Error *local_err = NULL;
+ int64_t base_size, top_size;
+ uint64_t perms, iter_shared_perms;
int ret;
assert(top != bs);
- if (top == base) {
+ if (bdrv_skip_filters(top) == bdrv_skip_filters(base)) {
error_setg(errp, "Invalid files for merge: top and base are the same");
return;
}
+ base_size = bdrv_getlength(base);
+ if (base_size < 0) {
+ error_setg_errno(errp, -base_size, "Could not inquire base image size");
+ return;
+ }
+
+ top_size = bdrv_getlength(top);
+ if (top_size < 0) {
+ error_setg_errno(errp, -top_size, "Could not inquire top image size");
+ return;
+ }
+
+ perms = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE;
+ if (base_size < top_size) {
+ perms |= BLK_PERM_RESIZE;
+ }
+
s = block_job_create(job_id, &commit_job_driver, NULL, bs, 0, BLK_PERM_ALL,
speed, creation_flags, NULL, NULL, errp);
if (!s) {
@@ -301,17 +322,43 @@ void commit_start(const char *job_id, BlockDriverState *bs,
s->commit_top_bs = 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. */
+ /*
+ * Block all nodes between top and base, because they will
+ * disappear from the chain after this operation.
+ * Note that this assumes that the user is fine with removing all
+ * nodes (including R/W filters) between top and base. Assuring
+ * this is the responsibility of the interface (i.e. whoever calls
+ * commit_start()).
+ */
+ s->base_overlay = bdrv_find_overlay(top, base);
+ assert(s->base_overlay);
+
+ /*
+ * The topmost node with
+ * bdrv_skip_filters(filtered_base) == bdrv_skip_filters(base)
+ */
+ filtered_base = bdrv_cow_bs(s->base_overlay);
+ assert(bdrv_skip_filters(filtered_base) == bdrv_skip_filters(base));
+
+ /*
+ * 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.
+ */
+ iter_shared_perms = BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE;
+
+ for (iter = top; iter != base; iter = bdrv_filter_or_cow_bs(iter)) {
+ if (iter == filtered_base) {
+ /*
+ * From here on, all nodes are filters on the base. This
+ * allows us to share BLK_PERM_CONSISTENT_READ.
+ */
+ iter_shared_perms |= BLK_PERM_CONSISTENT_READ;
+ }
+
ret = block_job_add_bdrv(&s->common, "intermediate node", iter, 0,
- BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE,
- errp);
+ iter_shared_perms, errp);
if (ret < 0) {
goto fail;
}
@@ -328,9 +375,7 @@ void commit_start(const char *job_id, BlockDriverState *bs,
}
s->base = blk_new(s->common.job.aio_context,
- BLK_PERM_CONSISTENT_READ
- | BLK_PERM_WRITE
- | BLK_PERM_RESIZE,
+ perms,
BLK_PERM_CONSISTENT_READ
| BLK_PERM_GRAPH_MOD
| BLK_PERM_WRITE_UNCHANGED);
@@ -398,19 +443,22 @@ int bdrv_commit(BlockDriverState *bs)
if (!drv)
return -ENOMEDIUM;
- if (!bs->backing) {
+ backing_file_bs = bdrv_cow_bs(bs);
+
+ if (!backing_file_bs) {
return -ENOTSUP;
}
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, NULL) ||
- bdrv_op_is_blocked(bs->backing->bs, BLOCK_OP_TYPE_COMMIT_TARGET, NULL)) {
+ bdrv_op_is_blocked(backing_file_bs, BLOCK_OP_TYPE_COMMIT_TARGET, NULL))
+ {
return -EBUSY;
}
- ro = bs->backing->bs->read_only;
+ ro = backing_file_bs->read_only;
if (ro) {
- if (bdrv_reopen_set_read_only(bs->backing->bs, false, NULL)) {
+ if (bdrv_reopen_set_read_only(backing_file_bs, false, NULL)) {
return -EACCES;
}
}
@@ -428,8 +476,6 @@ int bdrv_commit(BlockDriverState *bs)
}
/* Insert commit_top block node above backing, so we can write to it */
- backing_file_bs = backing_bs(bs);
-
commit_top_bs = bdrv_new_open_driver(&bdrv_commit_top, NULL, BDRV_O_RDWR,
&local_err);
if (commit_top_bs == NULL) {
@@ -515,15 +561,13 @@ ro_cleanup:
qemu_vfree(buf);
blk_unref(backing);
- if (backing_file_bs) {
- bdrv_set_backing_hd(bs, backing_file_bs, &error_abort);
- }
+ bdrv_set_backing_hd(bs, backing_file_bs, &error_abort);
bdrv_unref(commit_top_bs);
blk_unref(src);
if (ro) {
/* ignoring error return here */
- bdrv_reopen_set_read_only(bs->backing->bs, true, NULL);
+ bdrv_reopen_set_read_only(backing_file_bs, true, NULL);
}
return ret;
diff --git a/block/monitor/block-hmp-cmds.c b/block/monitor/block-hmp-cmds.c
index 4c8c375172..4d3db5ed3c 100644
--- a/block/monitor/block-hmp-cmds.c
+++ b/block/monitor/block-hmp-cmds.c
@@ -217,7 +217,7 @@ void hmp_commit(Monitor *mon, const QDict *qdict)
return;
}
- bs = blk_bs(blk);
+ bs = bdrv_skip_implicit_filters(blk_bs(blk));
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
diff --git a/blockdev.c b/blockdev.c
index 9ce99b9cbc..402f1d1df1 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2690,7 +2690,9 @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device,
assert(bdrv_get_aio_context(base_bs) == aio_context);
- for (iter = top_bs; iter != backing_bs(base_bs); iter = backing_bs(iter)) {
+ for (iter = top_bs; iter != bdrv_filter_or_cow_bs(base_bs);
+ iter = bdrv_filter_or_cow_bs(iter))
+ {
if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
goto out;
}
--
2.26.2
next prev parent reply other threads:[~2020-06-25 15:44 UTC|newest]
Thread overview: 173+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-25 15:21 [PATCH v7 00/47] block: Deal with filters Max Reitz
2020-06-25 15:21 ` [PATCH v7 01/47] block: Add child access functions Max Reitz
2020-07-08 17:22 ` Andrey Shinkevich
2020-07-13 9:06 ` Vladimir Sementsov-Ogievskiy
2020-07-16 14:46 ` Max Reitz
2020-07-28 16:09 ` Christophe de Dinechin
2020-08-07 9:33 ` Vladimir Sementsov-Ogievskiy
2020-07-13 9:57 ` Vladimir Sementsov-Ogievskiy
2020-06-25 15:21 ` [PATCH v7 02/47] block: Add chain helper functions Max Reitz
2020-07-08 17:20 ` Andrey Shinkevich
2020-07-09 8:24 ` Max Reitz
2020-07-09 9:07 ` Andrey Shinkevich
2020-07-13 10:18 ` Vladimir Sementsov-Ogievskiy
2020-07-16 14:50 ` Max Reitz
2020-07-16 15:24 ` Vladimir Sementsov-Ogievskiy
2020-06-25 15:21 ` [PATCH v7 03/47] block: bdrv_cow_child() for bdrv_has_zero_init() Max Reitz
2020-07-08 17:23 ` Andrey Shinkevich
2020-08-07 9:37 ` Vladimir Sementsov-Ogievskiy
2020-06-25 15:21 ` [PATCH v7 04/47] block: bdrv_set_backing_hd() is about bs->backing Max Reitz
2020-07-08 17:24 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 05/47] block: Include filters when freezing backing chain Max Reitz
2020-07-08 17:25 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 06/47] block: Drop bdrv_is_encrypted() Max Reitz
2020-07-08 17:41 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 07/47] block: Add bdrv_supports_compressed_writes() Max Reitz
2020-07-08 17:48 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 08/47] throttle: Support compressed writes Max Reitz
2020-07-08 17:52 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 09/47] copy-on-read: " Max Reitz
2020-07-08 17:54 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 10/47] mirror-top: " Max Reitz
2020-07-08 17:58 ` Andrey Shinkevich
2020-08-18 10:27 ` Kevin Wolf
2020-08-19 15:35 ` Max Reitz
2020-08-19 16:00 ` Kevin Wolf
2020-06-25 15:21 ` [PATCH v7 11/47] backup-top: " Max Reitz
2020-07-08 17:59 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 12/47] block: Use bdrv_filter_(bs|child) where obvious Max Reitz
2020-07-08 18:24 ` Andrey Shinkevich
2020-07-09 8:59 ` Max Reitz
2020-07-09 9:11 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 13/47] block: Use CAFs in block status functions Max Reitz
2020-07-08 19:13 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 14/47] stream: Deal with filters Max Reitz
2020-07-09 14:52 ` Andrey Shinkevich
2020-07-09 15:27 ` Andrey Shinkevich
2020-07-10 15:24 ` Max Reitz
2020-07-10 17:41 ` Andrey Shinkevich
2020-07-16 14:59 ` Max Reitz
2020-08-07 10:29 ` Vladimir Sementsov-Ogievskiy
2020-08-10 8:12 ` Max Reitz
2020-08-10 11:04 ` Vladimir Sementsov-Ogievskiy
2020-08-14 15:18 ` Andrey Shinkevich
2020-08-18 20:45 ` Andrey Shinkevich
2020-08-19 12:39 ` Max Reitz
2020-08-19 13:18 ` Vladimir Sementsov-Ogievskiy
2020-07-09 15:13 ` Andrey Shinkevich
2020-07-10 15:27 ` Max Reitz
2020-08-18 14:28 ` Kevin Wolf
2020-08-19 14:47 ` Max Reitz
2020-08-19 15:16 ` Kevin Wolf
2020-08-20 8:31 ` Max Reitz
2020-08-20 9:22 ` Max Reitz
2020-08-20 10:49 ` Vladimir Sementsov-Ogievskiy
2020-08-20 11:43 ` Max Reitz
2020-06-25 15:21 ` [PATCH v7 15/47] block: Use CAFs when working with backing chains Max Reitz
2020-07-10 15:28 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 16/47] block: Use bdrv_cow_child() in bdrv_co_truncate() Max Reitz
2020-07-10 15:54 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 17/47] block: Re-evaluate backing file handling in reopen Max Reitz
2020-07-10 19:42 ` Andrey Shinkevich
2020-07-16 15:04 ` Max Reitz
2020-06-25 15:21 ` [PATCH v7 18/47] block: Flush all children in generic code Max Reitz
2020-07-14 12:52 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 19/47] vmdk: Drop vmdk_co_flush() Max Reitz
2020-07-14 14:52 ` Andrey Shinkevich
2020-07-16 15:08 ` Max Reitz
2020-06-25 15:21 ` [PATCH v7 20/47] block: Iterate over children in refresh_limits Max Reitz
2020-07-14 18:37 ` Andrey Shinkevich
2020-07-16 15:14 ` Max Reitz
2020-06-25 15:21 ` [PATCH v7 21/47] block: Use CAFs in bdrv_refresh_filename() Max Reitz
2020-07-15 12:52 ` Andrey Shinkevich
2020-07-15 12:58 ` Andrey Shinkevich
2020-07-16 15:21 ` Max Reitz
2020-06-25 15:21 ` [PATCH v7 22/47] block: Use CAF in bdrv_co_rw_vmstate() Max Reitz
2020-07-15 13:39 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 23/47] block/snapshot: Fix fallback Max Reitz
2020-07-15 21:22 ` Andrey Shinkevich
2020-07-15 22:18 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 24/47] block: Use CAFs for debug breakpoints Max Reitz
2020-07-15 21:43 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 25/47] block: Def. impl.s for get_allocated_file_size Max Reitz
2020-07-15 22:56 ` Andrey Shinkevich
2020-08-19 10:57 ` Kevin Wolf
2020-08-19 15:53 ` Max Reitz
2020-06-25 15:21 ` [PATCH v7 26/47] block: Improve get_allocated_file_size's default Max Reitz
2020-07-20 15:12 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 27/47] blkverify: Use bdrv_sum_allocated_file_size() Max Reitz
2020-07-20 15:10 ` Andrey Shinkevich
2020-08-19 10:46 ` Kevin Wolf
2020-08-19 15:50 ` Max Reitz
2020-06-25 15:21 ` [PATCH v7 28/47] block/null: Implement bdrv_get_allocated_file_size Max Reitz
2020-07-20 15:10 ` Andrey Shinkevich
2020-07-24 8:58 ` Max Reitz
2020-07-24 9:49 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 29/47] blockdev: Use CAF in external_snapshot_prepare() Max Reitz
2020-07-20 16:08 ` Andrey Shinkevich
2020-07-24 9:23 ` Max Reitz
2020-07-24 10:37 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 30/47] block: Report data child for query-blockstats Max Reitz
2020-07-21 11:48 ` Andrey Shinkevich
2020-06-25 15:21 ` [PATCH v7 31/47] block: Use child access functions for QAPI queries Max Reitz
2020-07-21 12:30 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 32/47] block-copy: Use CAF to find sync=top base Max Reitz
2020-07-21 12:42 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 33/47] mirror: Deal with filters Max Reitz
2020-07-22 18:31 ` Andrey Shinkevich
2020-07-24 9:49 ` Max Reitz
2020-07-24 10:27 ` Andrey Shinkevich
2020-08-19 16:50 ` Kevin Wolf
2020-08-20 10:28 ` Max Reitz
2020-06-25 15:22 ` [PATCH v7 34/47] backup: " Max Reitz
2020-07-23 15:51 ` Andrey Shinkevich
2020-07-24 9:55 ` Max Reitz
2020-06-25 15:22 ` Max Reitz [this message]
2020-07-23 17:15 ` [PATCH v7 35/47] commit: " Andrey Shinkevich
2020-07-24 10:36 ` Andrey Shinkevich
2020-08-19 17:58 ` Kevin Wolf
2020-08-20 11:27 ` Max Reitz
2020-08-20 13:47 ` Kevin Wolf
2020-06-25 15:22 ` [PATCH v7 36/47] nbd: Use CAF when looking for dirty bitmap Max Reitz
2020-07-23 17:21 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 37/47] qemu-img: Use child access functions Max Reitz
2020-07-24 15:51 ` Andrey Shinkevich
2020-08-21 15:29 ` Kevin Wolf
2020-08-24 12:42 ` Max Reitz
2020-06-25 15:22 ` [PATCH v7 38/47] block: Drop backing_bs() Max Reitz
2020-07-24 15:55 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 39/47] blockdev: Fix active commit choice Max Reitz
2020-08-21 15:50 ` Kevin Wolf
2020-08-24 13:18 ` Max Reitz
2020-08-24 14:07 ` Kevin Wolf
2020-08-24 14:41 ` Max Reitz
2020-08-24 15:06 ` Kevin Wolf
2020-06-25 15:22 ` [PATCH v7 40/47] block: Inline bdrv_co_block_status_from_*() Max Reitz
2020-07-24 18:00 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 41/47] block: Leave BDS.backing_file constant Max Reitz
2020-07-27 12:27 ` Andrey Shinkevich
2020-07-28 14:10 ` Max Reitz
2020-08-24 13:14 ` Kevin Wolf
2020-08-24 14:29 ` Max Reitz
2020-06-25 15:22 ` [PATCH v7 42/47] iotests: Test that qcow2's data-file is flushed Max Reitz
2020-07-27 13:28 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 43/47] iotests: Let complete_and_wait() work with commit Max Reitz
2020-07-27 13:35 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 44/47] iotests: Add filter commit test cases Max Reitz
2020-07-27 17:45 ` Andrey Shinkevich
2020-07-28 14:00 ` Max Reitz
2020-06-25 15:22 ` [PATCH v7 45/47] iotests: Add filter mirror " Max Reitz
2020-08-02 11:05 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 46/47] iotests: Add test for commit in sub directory Max Reitz
2020-08-02 12:13 ` Andrey Shinkevich
2020-06-25 15:22 ` [PATCH v7 47/47] iotests: Test committing to overridden backing Max Reitz
2020-08-02 11:43 ` Andrey Shinkevich
2020-07-08 17:20 ` [PATCH v7 00/47] block: Deal with filters Andrey Shinkevich
2020-07-08 17:32 ` Eric Blake
2020-07-08 19:46 ` Andrey Shinkevich
2020-07-08 20:37 ` Eric Blake
2020-07-09 8:19 ` Max Reitz
2020-07-08 20:47 ` Eric Blake
2020-07-09 8:20 ` Max Reitz
2020-07-09 9:04 ` Andrey Shinkevich
2020-08-24 15:15 ` Kevin Wolf
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