[PATCH 20/32] db: introduce verifier support into set_cur

Dave Chinner
2013-09-30T03:16:02Z

To be able to use read and write verifiers, we need to pass the
verifier to the IO routines. We do this via the set_cur() function
used to trigger reading the buffer.

For most metadata types, there is only one type of verifier needed.
For these, we can simply add the verifier to the type table entry
for the given type and use that directly. This type entry is already
carried around by the IO context, so if we ever need to get it again
we have direct access to it in the context we'll be doing IO.

Only attach the verifiers to the v5 filesystem type table; there is
not need for them on v4 filesystems as we don't have to verify or
calculate CRCs for them.

There are some metadata types that have more than one buffer format,
or aren't based in directly in buffers. For these, leave the type
table verifier NULL for now - these will need to be addressed
individually.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
db/io.c | 13 +++++++---
db/type.c | 88 ++++++++++++++++++++++++++++++++++-----------------------------
db/type.h | 1 +
3 files changed, 59 insertions(+), 43 deletions(-)

diff --git a/db/io.c b/db/io.c
index 9129963..c9452f2 100644
--- a/db/io.c
+++ b/db/io.c
@@ -480,12 +480,14 @@ set_cur(
xfs_ino_t dirino;
xfs_ino_t ino;
__uint16_t mode;
+ const struct xfs_buf_ops *ops = t ? t->bops : NULL;

if (iocur_sp < 0) {
dbprintf(_("set_cur no stack element to set\n"));
return;
}

+
ino = iocur_top->ino;
dirino = iocur_top->dirino;
mode = iocur_top->mode;
@@ -507,12 +509,17 @@ set_cur(
return;
memcpy(iocur_top->bbmap, bbmap, sizeof(struct bbmap));
bp = libxfs_readbuf_map(mp->m_ddev_targp, bbmap->b,
- bbmap->nmaps, 0, NULL);
+ bbmap->nmaps, 0, ops);
} else {
- bp = libxfs_readbuf(mp->m_ddev_targp, d, c, 0, NULL);
+ bp = libxfs_readbuf(mp->m_ddev_targp, d, c, 0, ops);
iocur_top->bbmap = NULL;
}
- if (!bp || bp->b_error)
+
+ /*
+ * keep the buffer even if the verifier says it is corrupted.
+ * We're a diagnostic tool, after all.
+ */
+ if (!bp || (bp->b_error && bp->b_error != EFSCORRUPTED))
return;
iocur_top->buf = bp->b_addr;
iocur_top->bp = bp;
diff --git a/db/type.c b/db/type.c
index 64e2ef4..b3f3d87 100644
--- a/db/type.c
+++ b/db/type.c
@@ -50,50 +50,58 @@ static const cmdinfo_t type_cmd =
N_("set/show current data type"), NULL };

static const typ_t __typtab[] = {
- { TYP_AGF, "agf", handle_struct, agf_hfld },
- { TYP_AGFL, "agfl", handle_struct, agfl_hfld },
- { TYP_AGI, "agi", handle_struct, agi_hfld },
- { TYP_ATTR, "attr", handle_struct, attr_hfld },
- { TYP_BMAPBTA, "bmapbta", handle_struct, bmapbta_hfld },
- { TYP_BMAPBTD, "bmapbtd", handle_struct, bmapbtd_hfld },
- { TYP_BNOBT, "bnobt", handle_struct, bnobt_hfld },
- { TYP_CNTBT, "cntbt", handle_struct, cntbt_hfld },
- { TYP_DATA, "data", handle_block, NULL },
- { TYP_DIR2, "dir2", handle_struct, dir2_hfld },
- { TYP_DQBLK, "dqblk", handle_struct, dqblk_hfld },
- { TYP_INOBT, "inobt", handle_struct, inobt_hfld },
- { TYP_INODATA, "inodata", NULL, NULL },
- { TYP_INODE, "inode", handle_struct, inode_hfld },
- { TYP_LOG, "log", NULL, NULL },
- { TYP_RTBITMAP, "rtbitmap", NULL, NULL },
- { TYP_RTSUMMARY, "rtsummary", NULL, NULL },
- { TYP_SB, "sb", handle_struct, sb_hfld },
- { TYP_SYMLINK, "symlink", handle_string, NULL },
- { TYP_TEXT, "text", handle_text, NULL },
+ { TYP_AGF, "agf", handle_struct, agf_hfld, NULL },
+ { TYP_AGFL, "agfl", handle_struct, agfl_hfld, NULL },
+ { TYP_AGI, "agi", handle_struct, agi_hfld, NULL },
+ { TYP_ATTR, "attr", handle_struct, attr_hfld, NULL },
+ { TYP_BMAPBTA, "bmapbta", handle_struct, bmapbta_hfld, NULL },
+ { TYP_BMAPBTD, "bmapbtd", handle_struct, bmapbtd_hfld, NULL },
+ { TYP_BNOBT, "bnobt", handle_struct, bnobt_hfld, NULL },
+ { TYP_CNTBT, "cntbt", handle_struct, cntbt_hfld, NULL },
+ { TYP_DATA, "data", handle_block, NULL, NULL },
+ { TYP_DIR2, "dir2", handle_struct, dir2_hfld, NULL },
+ { TYP_DQBLK, "dqblk", handle_struct, dqblk_hfld, NULL },
+ { TYP_INOBT, "inobt", handle_struct, inobt_hfld, NULL },
+ { TYP_INODATA, "inodata", NULL, NULL, NULL },
+ { TYP_INODE, "inode", handle_struct, inode_hfld, NULL },
+ { TYP_LOG, "log", NULL, NULL, NULL },
+ { TYP_RTBITMAP, "rtbitmap", NULL, NULL, NULL },
+ { TYP_RTSUMMARY, "rtsummary", NULL, NULL, NULL },
+ { TYP_SB, "sb", handle_struct, sb_hfld, NULL },
+ { TYP_SYMLINK, "symlink", handle_string, NULL, NULL },
+ { TYP_TEXT, "text", handle_text, NULL, NULL },
{ TYP_NONE, NULL }
};

static const typ_t __typtab_crc[] = {
- { TYP_AGF, "agf", handle_struct, agf_hfld },
- { TYP_AGFL, "agfl", handle_struct, agfl_crc_hfld },
- { TYP_AGI, "agi", handle_struct, agi_hfld },
- { TYP_ATTR, "attr3", handle_struct, attr3_hfld },
- { TYP_BMAPBTA, "bmapbta", handle_struct, bmapbta_crc_hfld },
- { TYP_BMAPBTD, "bmapbtd", handle_struct, bmapbtd_crc_hfld },
- { TYP_BNOBT, "bnobt", handle_struct, bnobt_crc_hfld },
- { TYP_CNTBT, "cntbt", handle_struct, cntbt_crc_hfld },
- { TYP_DATA, "data", handle_block, NULL },
- { TYP_DIR2, "dir3", handle_struct, dir3_hfld },
- { TYP_DQBLK, "dqblk", handle_struct, dqblk_hfld },
- { TYP_INOBT, "inobt", handle_struct, inobt_crc_hfld },
- { TYP_INODATA, "inodata", NULL, NULL },
- { TYP_INODE, "inode", handle_struct, inode_crc_hfld },
- { TYP_LOG, "log", NULL, NULL },
- { TYP_RTBITMAP, "rtbitmap", NULL, NULL },
- { TYP_RTSUMMARY, "rtsummary", NULL, NULL },
- { TYP_SB, "sb", handle_struct, sb_hfld },
- { TYP_SYMLINK, "symlink", handle_struct, symlink_crc_hfld },
- { TYP_TEXT, "text", handle_text, NULL },
+ { TYP_AGF, "agf", handle_struct, agf_hfld, &xfs_agf_buf_ops },
+ { TYP_AGFL, "agfl", handle_struct, agfl_crc_hfld, &xfs_agfl_buf_ops },
+ { TYP_AGI, "agi", handle_struct, agi_hfld, &xfs_agfl_buf_ops },
+ { TYP_ATTR, "attr3", handle_struct, attr3_hfld, NULL },
+ { TYP_BMAPBTA, "bmapbta", handle_struct, bmapbta_crc_hfld,
+ &xfs_bmbt_buf_ops },
+ { TYP_BMAPBTD, "bmapbtd", handle_struct, bmapbtd_crc_hfld,
+ &xfs_bmbt_buf_ops },
+ { TYP_BNOBT, "bnobt", handle_struct, bnobt_crc_hfld,
+ &xfs_allocbt_buf_ops },
+ { TYP_CNTBT, "cntbt", handle_struct, cntbt_crc_hfld,
+ &xfs_allocbt_buf_ops },
+ { TYP_DATA, "data", handle_block, NULL, NULL },
+ { TYP_DIR2, "dir3", handle_struct, dir3_hfld, NULL },
+ { TYP_DQBLK, "dqblk", handle_struct, dqblk_hfld,
+ &xfs_dquot_buf_ops },
+ { TYP_INOBT, "inobt", handle_struct, inobt_crc_hfld,
+ &xfs_inobt_buf_ops },
+ { TYP_INODATA, "inodata", NULL, NULL, NULL },
+ { TYP_INODE, "inode", handle_struct, inode_crc_hfld,
+ &xfs_inode_buf_ops },
+ { TYP_LOG, "log", NULL, NULL, NULL },
+ { TYP_RTBITMAP, "rtbitmap", NULL, NULL, NULL },
+ { TYP_RTSUMMARY, "rtsummary", NULL, NULL, NULL },
+ { TYP_SB, "sb", handle_struct, sb_hfld, &xfs_sb_buf_ops },
+ { TYP_SYMLINK, "symlink", handle_struct, symlink_crc_hfld,
+ &xfs_symlink_buf_ops },
+ { TYP_TEXT, "text", handle_text, NULL, NULL },
{ TYP_NONE, NULL }
};

diff --git a/db/type.h b/db/type.h
index c41aca4d..3bb26f1 100644
--- a/db/type.h
+++ b/db/type.h
@@ -42,6 +42,7 @@ typedef struct typ
char *name;
pfunc_t pfunc;
const struct field *fields;
+ const struct xfs_buf_ops *bops;
} typ_t;
extern const typ_t *typtab, *cur_typ;