OpenE2K
/
qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

block/qcow2: Lock s->lock in preallocate() 

preallocate() is and will be called only from places that do not
otherwise need to lock s->lock: Currently that is qcow2_create2(), as of
a future patch it will be called from qcow2_truncate(), too.

It therefore makes sense to move locking that mutex into preallocate()
itself.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-11-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Max Reitz 2017-06-13 22:21:01 +02:00
parent 7bc45dc172
commit 652fecd005
1 changed files with 15 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
block/qcow2.c
View File

@ -2486,12 +2486,17 @@ static int qcow2_set_up_encryption(BlockDriverState *bs, const char *encryptfmt,
static int preallocate(BlockDriverState *bs,
uint64_t offset, uint64_t new_length)
{
BDRVQcow2State *s = bs->opaque;
uint64_t bytes;
uint64_t host_offset = 0;
unsigned int cur_bytes;
int ret;
QCowL2Meta *meta;
if (qemu_in_coroutine()) {
qemu_co_mutex_lock(&s->lock);
}
assert(offset <= new_length);
bytes = new_length - offset;
@ -2500,7 +2505,7 @@ static int preallocate(BlockDriverState *bs,
ret = qcow2_alloc_cluster_offset(bs, offset, &cur_bytes,
&host_offset, &meta);
if (ret < 0) {
return ret;
goto done;
}
while (meta) {
@ -2510,7 +2515,7 @@ static int preallocate(BlockDriverState *bs,
if (ret < 0) {
qcow2_free_any_clusters(bs, meta->alloc_offset,
meta->nb_clusters, QCOW2_DISCARD_NEVER);
return ret;
goto done;
}
/* There are no dependent requests, but we need to remove our
@ -2537,11 +2542,17 @@ static int preallocate(BlockDriverState *bs,
ret = bdrv_pwrite(bs->file, (host_offset + cur_bytes) - 1,
&data, 1);
if (ret < 0) {
return ret;
goto done;
}
}
return 0;
ret = 0;
done:
if (qemu_in_coroutine()) {
qemu_co_mutex_unlock(&s->lock);
}
return ret;
}
/* qcow2_refcount_metadata_size:
@ -2835,10 +2846,7 @@ static int qcow2_create2(const char *filename, int64_t total_size,
/* And if we're supposed to preallocate metadata, do that now */
if (prealloc != PREALLOC_MODE_OFF) {
BDRVQcow2State *s = blk_bs(blk)->opaque;
qemu_co_mutex_lock(&s->lock);
ret = preallocate(blk_bs(blk), 0, total_size);
qemu_co_mutex_unlock(&s->lock);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not preallocate metadata");
goto out;