raw-posix: remember whether discard failed

Avoid sending system calls repeatedly if they shall fail.  This
does not apply to XFS: if the filesystem-specific ioctl fails,
something weird is happening.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Paolo Bonzini 2013-01-14 16:26:53 +01:00 committed by Stefan Hajnoczi
parent 3d4fa43e64
commit c85191e5c9
1 changed files with 6 additions and 3 deletions

View File

@ -141,6 +141,7 @@ typedef struct BDRVRawState {
#ifdef CONFIG_XFS
bool is_xfs : 1;
#endif
bool has_discard : 1;
} BDRVRawState;
typedef struct BDRVRawReopenState {
@ -292,6 +293,7 @@ static int raw_open_common(BlockDriverState *bs, const char *filename,
}
#endif
s->has_discard = 1;
#ifdef CONFIG_XFS
if (platform_test_xfs_fd(s->fd)) {
s->is_xfs = 1;
@ -1078,10 +1080,12 @@ static coroutine_fn int raw_co_discard(BlockDriverState *bs,
int64_t sector_num, int nb_sectors)
{
int ret = -EOPNOTSUPP;
#if defined(CONFIG_FALLOCATE_PUNCH_HOLE) || defined(CONFIG_XFS)
BDRVRawState *s = bs->opaque;
if (!s->has_discard) {
return 0;
}
#ifdef CONFIG_XFS
if (s->is_xfs) {
return xfs_discard(s, sector_num, nb_sectors);
@ -1098,7 +1102,6 @@ static coroutine_fn int raw_co_discard(BlockDriverState *bs,
} while (errno == EINTR);
ret = -errno;
#endif
#endif
if (ret == -EOPNOTSUPP) {