diff options
| author | Hanna Reitz <hreitz@redhat.com> | 2022-08-03 16:44:45 +0200 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2022-09-30 18:43:44 +0200 |
| commit | dc70638ff616ef0a1a6e4f61ce1f3f5282d2c942 (patch) | |
| tree | afb1d95c5244682d7c3cce011c6416eb356c7724 /block/qed.c | |
| parent | ec64b1ca08138b5f57d270a5756a9138f897ee5a (diff) | |
block/qed: Keep auto_backing_file if possible
Just like qcow2, qed invokes its open function in its
.bdrv_co_invalidate_cache() implementation. Therefore, just like done
for qcow2 in HEAD^, update auto_backing_file only if the backing file
string in the image header differs from the one we have read before.
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220803144446.20723-3-hreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block/qed.c')
| -rw-r--r-- | block/qed.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/block/qed.c b/block/qed.c index 40943e679b..324ca0e95a 100644 --- a/block/qed.c +++ b/block/qed.c @@ -445,6 +445,8 @@ static int coroutine_fn bdrv_qed_do_open(BlockDriverState *bs, QDict *options, } if ((s->header.features & QED_F_BACKING_FILE)) { + g_autofree char *backing_file_str = NULL; + if ((uint64_t)s->header.backing_filename_offset + s->header.backing_filename_size > s->header.cluster_size * s->header.header_size) { @@ -452,16 +454,21 @@ static int coroutine_fn bdrv_qed_do_open(BlockDriverState *bs, QDict *options, return -EINVAL; } + backing_file_str = g_malloc(sizeof(bs->backing_file)); ret = qed_read_string(bs->file, s->header.backing_filename_offset, s->header.backing_filename_size, - bs->auto_backing_file, - sizeof(bs->auto_backing_file)); + backing_file_str, sizeof(bs->backing_file)); if (ret < 0) { error_setg(errp, "Failed to read backing filename"); return ret; } - pstrcpy(bs->backing_file, sizeof(bs->backing_file), - bs->auto_backing_file); + + if (!g_str_equal(backing_file_str, bs->backing_file)) { + pstrcpy(bs->backing_file, sizeof(bs->backing_file), + backing_file_str); + pstrcpy(bs->auto_backing_file, sizeof(bs->auto_backing_file), + backing_file_str); + } if (s->header.features & QED_F_BACKING_FORMAT_NO_PROBE) { pstrcpy(bs->backing_format, sizeof(bs->backing_format), "raw"); |