summaryrefslogtreecommitdiff
path: root/fs/xfs/xfs_log.c
diff options
context:
space:
mode:
authorDave Chinner <david@fromorbit.com>2015-10-12 18:37:58 +1100
committerDave Chinner <david@fromorbit.com>2015-10-12 18:37:58 +1100
commit316433beda9433697109eb1cd256666f163c7c1f (patch)
tree14dc948e98bf1d5a1bbbe86cffb7da9a2952325b /fs/xfs/xfs_log.c
parent9e92054e8e049f8f4c64d2c6961b2a7e3e13977f (diff)
parent91f9f5fe1e7350e872b3fbc3194e8183bddce514 (diff)
Merge branch 'xfs-logging-fixes' into for-next
Diffstat (limited to 'fs/xfs/xfs_log.c')
-rw-r--r--fs/xfs/xfs_log.c71
1 files changed, 65 insertions, 6 deletions
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 401252360a62..f52c72a1a06f 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -2422,11 +2422,20 @@ xlog_write(
&partial_copy_len);
xlog_verify_dest_ptr(log, ptr);
- /* copy region */
+ /*
+ * Copy region.
+ *
+ * Unmount records just log an opheader, so can have
+ * empty payloads with no data region to copy. Hence we
+ * only copy the payload if the vector says it has data
+ * to copy.
+ */
ASSERT(copy_len >= 0);
- memcpy(ptr, reg->i_addr + copy_off, copy_len);
- xlog_write_adv_cnt(&ptr, &len, &log_offset, copy_len);
-
+ if (copy_len > 0) {
+ memcpy(ptr, reg->i_addr + copy_off, copy_len);
+ xlog_write_adv_cnt(&ptr, &len, &log_offset,
+ copy_len);
+ }
copy_len += start_rec_copy + sizeof(xlog_op_header_t);
record_cnt++;
data_cnt += contwr ? copy_len : 0;
@@ -3165,11 +3174,19 @@ xlog_state_switch_iclogs(
}
if (log->l_curr_block >= log->l_logBBsize) {
+ /*
+ * Rewind the current block before the cycle is bumped to make
+ * sure that the combined LSN never transiently moves forward
+ * when the log wraps to the next cycle. This is to support the
+ * unlocked sample of these fields from xlog_valid_lsn(). Most
+ * other cases should acquire l_icloglock.
+ */
+ log->l_curr_block -= log->l_logBBsize;
+ ASSERT(log->l_curr_block >= 0);
+ smp_wmb();
log->l_curr_cycle++;
if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM)
log->l_curr_cycle++;
- log->l_curr_block -= log->l_logBBsize;
- ASSERT(log->l_curr_block >= 0);
}
ASSERT(iclog == log->l_iclog);
log->l_iclog = iclog->ic_next;
@@ -4023,3 +4040,45 @@ xlog_iclogs_empty(
return 1;
}
+/*
+ * Verify that an LSN stamped into a piece of metadata is valid. This is
+ * intended for use in read verifiers on v5 superblocks.
+ */
+bool
+xfs_log_check_lsn(
+ struct xfs_mount *mp,
+ xfs_lsn_t lsn)
+{
+ struct xlog *log = mp->m_log;
+ bool valid;
+
+ /*
+ * norecovery mode skips mount-time log processing and unconditionally
+ * resets the in-core LSN. We can't validate in this mode, but
+ * modifications are not allowed anyways so just return true.
+ */
+ if (mp->m_flags & XFS_MOUNT_NORECOVERY)
+ return true;
+
+ /*
+ * Some metadata LSNs are initialized to NULL (e.g., the agfl). This is
+ * handled by recovery and thus safe to ignore here.
+ */
+ if (lsn == NULLCOMMITLSN)
+ return true;
+
+ valid = xlog_valid_lsn(mp->m_log, lsn);
+
+ /* warn the user about what's gone wrong before verifier failure */
+ if (!valid) {
+ spin_lock(&log->l_icloglock);
+ xfs_warn(mp,
+"Corruption warning: Metadata has LSN (%d:%d) ahead of current LSN (%d:%d). "
+"Please unmount and run xfs_repair (>= v4.3) to resolve.",
+ CYCLE_LSN(lsn), BLOCK_LSN(lsn),
+ log->l_curr_cycle, log->l_curr_block);
+ spin_unlock(&log->l_icloglock);
+ }
+
+ return valid;
+}