diff options
| author | Max Reitz <mreitz@redhat.com> | 2018-05-09 22:00:58 +0200 |
|---|---|---|
| committer | Max Reitz <mreitz@redhat.com> | 2018-06-11 16:18:45 +0200 |
| commit | 3cce51c919c7b4028cf6676dfcb80a45741b5117 (patch) | |
| tree | 1e06c390b806585bafc811e759f858f998405e2c /block/qcow2-refcount.c | |
| parent | dee6ddd8a6b7978d0bc8ef8e1f006282ce30e4fa (diff) | |
qcow2: Repair OFLAG_COPIED when fixing leaks
Repairing OFLAG_COPIED is usually safe because it is done after the
refcounts have been repaired. Therefore, it we did not find anyone else
referencing a data or L2 cluster, it makes no sense to not set
OFLAG_COPIED -- and the other direction (clearing OFLAG_COPIED) is
always safe, anyway, it may just induce leaks.
Furthermore, if OFLAG_COPIED is actually consistent with a wrong (leaky)
refcount, we will decrement the refcount with -r leaks, but OFLAG_COPIED
will then be wrong. qemu-img check should not produce images that are
more corrupted afterwards then they were before.
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1527085
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20180509200059.31125-2-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Diffstat (limited to 'block/qcow2-refcount.c')
| -rw-r--r-- | block/qcow2-refcount.c | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 403236256b..18c729aa27 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -1799,6 +1799,19 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res, int ret; uint64_t refcount; int i, j; + bool repair; + + if (fix & BDRV_FIX_ERRORS) { + /* Always repair */ + repair = true; + } else if (fix & BDRV_FIX_LEAKS) { + /* Repair only if that seems safe: This function is always + * called after the refcounts have been fixed, so the refcount + * is accurate if that repair was successful */ + repair = !res->check_errors && !res->corruptions && !res->leaks; + } else { + repair = false; + } for (i = 0; i < s->l1_size; i++) { uint64_t l1_entry = s->l1_table[i]; @@ -1818,10 +1831,8 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res, if ((refcount == 1) != ((l1_entry & QCOW_OFLAG_COPIED) != 0)) { fprintf(stderr, "%s OFLAG_COPIED L2 cluster: l1_index=%d " "l1_entry=%" PRIx64 " refcount=%" PRIu64 "\n", - fix & BDRV_FIX_ERRORS ? "Repairing" : - "ERROR", - i, l1_entry, refcount); - if (fix & BDRV_FIX_ERRORS) { + repair ? "Repairing" : "ERROR", i, l1_entry, refcount); + if (repair) { s->l1_table[i] = refcount == 1 ? l1_entry | QCOW_OFLAG_COPIED : l1_entry & ~QCOW_OFLAG_COPIED; @@ -1862,10 +1873,8 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res, if ((refcount == 1) != ((l2_entry & QCOW_OFLAG_COPIED) != 0)) { fprintf(stderr, "%s OFLAG_COPIED data cluster: " "l2_entry=%" PRIx64 " refcount=%" PRIu64 "\n", - fix & BDRV_FIX_ERRORS ? "Repairing" : - "ERROR", - l2_entry, refcount); - if (fix & BDRV_FIX_ERRORS) { + repair ? "Repairing" : "ERROR", l2_entry, refcount); + if (repair) { l2_table[j] = cpu_to_be64(refcount == 1 ? l2_entry | QCOW_OFLAG_COPIED : l2_entry & ~QCOW_OFLAG_COPIED); |