[PATCH 08/10] xfs_db: enable blocktrash for checksummed filesystems

Darrick J. Wong
2015-08-15T01:44:34Z

Disable the write verifiers when we're trashing a block. With this
in place, create a xfs fuzzer script that formats, populates, corrupts,
tries to use, repairs, and tries again to use a crash test xfs image.
Hopefully this will shake out some v5 filesystem bugs.

v2: Drop xfsfuzz, don't assume every block is an AGF when blocktrashing.
Don't trash log blocks by default, because that skews the blocktrash
heavily towards damaging only log blocks.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
db/check.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/db/check.c b/db/check.c
index afeea32..965d0f5 100644
--- a/db/check.c
+++ b/db/check.c
@@ -944,6 +944,7 @@ blocktrash_b(
int mask;
int newbit;
int offset;
+ const struct xfs_buf_ops *stashed_ops;
static char *modestr[] = {
N_("zeroed"), N_("set"), N_("flipped"), N_("randomized")
};
@@ -952,8 +953,10 @@ blocktrash_b(
offset = (int)(random() % (int)(mp->m_sb.sb_blocksize * NBBY));
newbit = 0;
push_cur();
- set_cur(&typtab[DBM_UNKNOWN],
+ set_cur(NULL,
XFS_AGB_TO_DADDR(mp, agno, agbno), blkbb, DB_RING_IGN, NULL);
+ stashed_ops = iocur_top->bp->b_ops;
+ iocur_top->bp->b_ops = NULL;
if ((buf = iocur_top->data) == NULL) {
dbprintf(_("can't read block %u/%u for trashing\n"), agno, agbno);
pop_cur();
@@ -984,6 +987,7 @@ blocktrash_b(
buf[byte] &= ~mask;
}
write_cur();
+ iocur_top->bp->b_ops = stashed_ops;
pop_cur();
printf(_("blocktrash: %u/%u %s block %d bit%s starting %d:%d %s\n"),
agno, agbno, typename[type], len, len == 1 ? "" : "s",
@@ -1040,9 +1044,11 @@ blocktrash_f(
(1 << DBM_BTINO) |
(1 << DBM_DIR) |
(1 << DBM_INODE) |
+ (1 << DBM_LOG) |
(1 << DBM_QUOTA) |
(1 << DBM_RTBITMAP) |
(1 << DBM_RTSUM) |
+ (1 << DBM_SYMLINK) |
(1 << DBM_SB);
while ((c = getopt(argc, argv, "0123n:s:t:x:y:")) != EOF) {
switch (c) {
@@ -1106,7 +1112,7 @@ blocktrash_f(
return 0;
}
if (tmask == 0)
- tmask = goodmask;
+ tmask = goodmask & ~((1 << DBM_LOG) | (1 << DBM_SB));
lentab = xmalloc(sizeof(ltab_t));
lentab->min = lentab->max = min;
lentablen = 1;