[PATCH 03/15] xfs_db: enable blocktrash for checksummed filesystems

["Darrick J. Wong" <darrick.wong@xxxxxxxxxx>]

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@xxxxxxxxxx>
---
 db/check.c |   11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)


diff --git a/db/check.c b/db/check.c
index 288b2ab..9b40725 100644
--- a/db/check.c
+++ b/db/check.c
@@ -935,6 +935,7 @@ 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")
        };
@@ -943,8 +944,10 @@ 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();
@@ -975,6 +978,7 @@ 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",
@@ -1031,9 +1035,12 @@ 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_BTFINO) |
                   (1 << DBM_SB);
        while ((c = getopt(argc, argv, "0123n:s:t:x:y:")) != EOF) {
                switch (c) {
@@ -1097,7 +1104,7 @@ 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;