LU-4941 lfsck: check LOV EA header properly

1) If the LFSCK does not recognize the magic, then check whether
   the magic's postfix match the LOV_MAGIC_MAGIC or not: if yes,
   then it is quite possible that the system was downgraded from
   a new release with new LOV magic, so it is better to keep the
   current LOV EA unchanged; otherwise, it is crashed LOV EA and
   should be repaired by the LFSCK.

2) Check the pattern with lov_pattern().

3) Drop redundant LOV EA header verification.

Signed-off-by: Fan Yong <fan.yong@intel.com>
Change-Id: Iad3a1d6fc50a5dfba977a534fdb253bc9f6373e5
Reviewed-on: http://review.whamcloud.com/10045
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/include/lustre/lustre_idl.h b/lustre/include/lustre/lustre_idl.h
index eccf646..b27d33f 100644 (file)
--- a/lustre/include/lustre/lustre_idl.h
+++ b/lustre/include/lustre/lustre_idl.h
@@ -1578,11 +1578,21 @@ enum obdo_flags {
         OBD_FL_LOCAL_MASK   = 0xF0000000,
 };
 
         OBD_FL_LOCAL_MASK   = 0xF0000000,
 };
 

-#define LOV_MAGIC_V1      0x0BD10BD0
-#define LOV_MAGIC         LOV_MAGIC_V1
-#define LOV_MAGIC_JOIN_V1 0x0BD20BD0
-#define LOV_MAGIC_V3      0x0BD30BD0
-#define LOV_MAGIC_MIGRATE 0x0BD40BD0
+/*
+ * All LOV EA magics should have the same postfix, if some new version
+ * Lustre instroduces new LOV EA magic, then when down-grade to an old
+ * Lustre, even though the old version system does not recognizes such
+ * new magic, it still can distinguish the corrupted cases by checking
+ * the magic's postfix.
+ */
+#define LOV_MAGIC_MAGIC 0x0BD0
+#define LOV_MAGIC_MASK  0xFFFF
+
+#define LOV_MAGIC_V1           (0x0BD10000 | LOV_MAGIC_MAGIC)
+#define LOV_MAGIC_JOIN_V1      (0x0BD20000 | LOV_MAGIC_MAGIC)
+#define LOV_MAGIC_V3           (0x0BD30000 | LOV_MAGIC_MAGIC)
+#define LOV_MAGIC_MIGRATE      (0x0BD40000 | LOV_MAGIC_MAGIC)
+#define LOV_MAGIC              LOV_MAGIC_V1

 
 /*
  * magic for fully defined striping
 
 /*
  * magic for fully defined striping

diff --git a/lustre/lfsck/lfsck_layout.c b/lustre/lfsck/lfsck_layout.c
index bd5c1fb..e9318a1 100644 (file)
--- a/lustre/lfsck/lfsck_layout.c
+++ b/lustre/lfsck/lfsck_layout.c
@@ -349,19 +349,40 @@ again:
 static int lfsck_layout_verify_header(struct lov_mds_md_v1 *lmm)
 {
        __u32 magic;
 static int lfsck_layout_verify_header(struct lov_mds_md_v1 *lmm)
 {
        __u32 magic;

-       __u32 patten;
+       __u32 pattern;

 
        magic = le32_to_cpu(lmm->lmm_magic);
        /* If magic crashed, keep it there. Sometime later, during OST-object
         * orphan handling, if some OST-object(s) back-point to it, it can be
         * verified and repaired. */
 
        magic = le32_to_cpu(lmm->lmm_magic);
        /* If magic crashed, keep it there. Sometime later, during OST-object
         * orphan handling, if some OST-object(s) back-point to it, it can be
         * verified and repaired. */

-       if (magic != LOV_MAGIC_V1 && magic != LOV_MAGIC_V3)
-               return -EINVAL;
+       if (magic != LOV_MAGIC_V1 && magic != LOV_MAGIC_V3) {
+               struct ost_id   oi;
+               int             rc;
+
+               lmm_oi_cpu_to_le(&oi, &lmm->lmm_oi);
+               if ((magic & LOV_MAGIC_MASK) == LOV_MAGIC_MAGIC)
+                       rc = -EOPNOTSUPP;
+               else
+                       rc = -EINVAL;

 
 

-       patten = le32_to_cpu(lmm->lmm_pattern);
+               CDEBUG(D_LFSCK, "%s LOV EA magic %u on "DOSTID"\n",
+                      rc == -EINVAL ? "Unknown" : "Unsupported",
+                      magic, POSTID(&oi));
+
+               return rc;
+       }
+
+       pattern = le32_to_cpu(lmm->lmm_pattern);

        /* XXX: currently, we only support LOV_PATTERN_RAID0. */
        /* XXX: currently, we only support LOV_PATTERN_RAID0. */

-       if (patten != LOV_PATTERN_RAID0)
+       if (lov_pattern(pattern) != LOV_PATTERN_RAID0) {
+               struct ost_id oi;
+
+               lmm_oi_cpu_to_le(&oi, &lmm->lmm_oi);
+               CDEBUG(D_LFSCK, "Unsupported LOV EA pattern %u on "DOSTID"\n",
+                      pattern, POSTID(&oi));
+

                return -EOPNOTSUPP;
                return -EOPNOTSUPP;

+       }

 
        return 0;
 }
 
        return 0;
 }


@@ -1710,14 +1731,14 @@ static int lfsck_layout_extend_lovea(const struct lu_env *env,
                                     struct dt_object *parent,
                                     struct lu_fid *cfid,
                                     struct lu_buf *buf, int fl,
                                     struct dt_object *parent,
                                     struct lu_fid *cfid,
                                     struct lu_buf *buf, int fl,

-                                    __u32 ost_idx, __u32 ea_off)
+                                    __u32 ost_idx, __u32 ea_off, bool reset)

 {
        struct lov_mds_md_v1    *lmm    = buf->lb_buf;
        struct lov_ost_data_v1  *objs;
        int                      rc;
        ENTRY;
 
 {
        struct lov_mds_md_v1    *lmm    = buf->lb_buf;
        struct lov_ost_data_v1  *objs;
        int                      rc;
        ENTRY;
 

-       if (fl == LU_XATTR_CREATE) {
+       if (fl == LU_XATTR_CREATE || reset) {

                LASSERT(buf->lb_len == lov_mds_md_size(ea_off + 1,
                                                       LOV_MAGIC_V1));
 
                LASSERT(buf->lb_len == lov_mds_md_size(ea_off + 1,
                                                       LOV_MAGIC_V1));
 


@@ -2006,7 +2027,7 @@ static int lfsck_layout_recreate_parent(const struct lu_env *env,
                /* 3b. Add layout EA for the MDT-object. */
                rc = lfsck_layout_extend_lovea(env, th, pobj, cfid, ea_buf,
                                               LU_XATTR_CREATE, ltd->ltd_index,
                /* 3b. Add layout EA for the MDT-object. */
                rc = lfsck_layout_extend_lovea(env, th, pobj, cfid, ea_buf,
                                               LU_XATTR_CREATE, ltd->ltd_index,

-                                              ea_off);
+                                              ea_off, false);

        dt_write_unlock(env, pobj);
        if (rc < 0)
                GOTO(stop, rc);
        dt_write_unlock(env, pobj);
        if (rc < 0)
                GOTO(stop, rc);


@@ -2406,13 +2427,30 @@ again:
 
                buf->lb_len = rc;
                rc = lfsck_layout_extend_lovea(env, handle, parent, cfid, buf,
 
                buf->lb_len = rc;
                rc = lfsck_layout_extend_lovea(env, handle, parent, cfid, buf,

-                                              fl, ost_idx, ea_off);
+                                              fl, ost_idx, ea_off, false);

 
                GOTO(unlock_parent, rc);
        }
 
        lmm = buf->lb_buf;
        rc1 = lfsck_layout_verify_header(lmm);
 
                GOTO(unlock_parent, rc);
        }
 
        lmm = buf->lb_buf;
        rc1 = lfsck_layout_verify_header(lmm);

+
+       /* If the LOV EA crashed, the rebuild it. */
+       if (rc1 == -EINVAL) {
+               if (bk->lb_param & LPF_DRYRUN)
+                       GOTO(unlock_parent, rc = 1);
+
+               LASSERT(buf->lb_len >= rc);
+
+               buf->lb_len = rc;
+               memset(lmm, 0, buf->lb_len);
+               rc = lfsck_layout_extend_lovea(env, handle, parent, cfid, buf,
+                                              fl, ost_idx, ea_off, true);
+
+               GOTO(unlock_parent, rc);
+       }
+
+       /* For other unknown magic/pattern, keep the current LOV EA. */

        if (rc1 != 0)
                GOTO(unlock_parent, rc = rc1);
 
        if (rc1 != 0)
                GOTO(unlock_parent, rc = rc1);
 


@@ -2445,7 +2483,7 @@ again:
 
                buf->lb_len = rc;
                rc = lfsck_layout_extend_lovea(env, handle, parent, cfid, buf,
 
                buf->lb_len = rc;
                rc = lfsck_layout_extend_lovea(env, handle, parent, cfid, buf,

-                                              fl, ost_idx, ea_off);
+                                              fl, ost_idx, ea_off, false);

                GOTO(unlock_parent, rc);
        }
 
                GOTO(unlock_parent, rc);
        }
 


@@ -2947,10 +2985,6 @@ static int lfsck_layout_repair_multiple_references(const struct lu_env *env,
                GOTO(unlock2, rc = 0);
 
        lmm = buf->lb_buf;
                GOTO(unlock2, rc = 0);
 
        lmm = buf->lb_buf;

-       rc = lfsck_layout_verify_header(lmm);
-       if (rc != 0)
-               GOTO(unlock2, rc);
-

        /* Someone change layout during the LFSCK, no need to repair then. */
        if (le16_to_cpu(lmm->lmm_layout_gen) != llr->llr_parent->llo_gen)
                GOTO(unlock2, rc = 0);
        /* Someone change layout during the LFSCK, no need to repair then. */
        if (le16_to_cpu(lmm->lmm_layout_gen) != llr->llr_parent->llo_gen)
                GOTO(unlock2, rc = 0);


@@ -3137,14 +3171,6 @@ static int lfsck_layout_check_parent(const struct lu_env *env,
                GOTO(out, rc);
 
        lmm = buf->lb_buf;
                GOTO(out, rc);
 
        lmm = buf->lb_buf;

-       rc = lfsck_layout_verify_header(lmm);
-       if (rc != 0)
-               GOTO(out, rc);
-
-       /* Currently, we only support LOV_MAGIC_V1/LOV_MAGIC_V3 which has
-        * been verified in lfsck_layout_verify_header() already. If some
-        * new magic introduced in the future, then layout LFSCK needs to
-        * be updated also. */

        magic = le32_to_cpu(lmm->lmm_magic);
        if (magic == LOV_MAGIC_V1) {
                objs = &(lmm->lmm_objects[0]);
        magic = le32_to_cpu(lmm->lmm_magic);
        if (magic == LOV_MAGIC_V1) {
                objs = &(lmm->lmm_objects[0]);


@@ -4487,6 +4513,8 @@ again:
        buf->lb_len = rc;
        lmm = buf->lb_buf;
        rc = lfsck_layout_verify_header(lmm);
        buf->lb_len = rc;
        lmm = buf->lb_buf;
        rc = lfsck_layout_verify_header(lmm);

+       /* If the LOV EA crashed, then it is possible to be rebuilt later
+        * when handle orphan OST-objects. */

        if (rc != 0)
                GOTO(out, rc);
 
        if (rc != 0)
                GOTO(out, rc);