LU-9857 lmv: dir page is released while in use

[fs/lustre-release.git] / lustre / lmv / lmv_obd.c

diff --git a/lustre/lmv/lmv_obd.c b/lustre/lmv/lmv_obd.c
index 2a6fbfe..5231b97 100644 (file)
--- a/lustre/lmv/lmv_obd.c
+++ b/lustre/lmv/lmv_obd.c
@@ -2054,7 +2054,7 @@ struct lmv_dir_ctxt {
        struct stripe_dirent     ldc_stripes[0];
 };
 
-static inline void put_stripe_dirent(struct stripe_dirent *stripe)
+static inline void stripe_dirent_unload(struct stripe_dirent *stripe)
 {
        if (stripe->sd_page) {
                kunmap(stripe->sd_page);
@@ -2069,58 +2069,78 @@ static inline void put_lmv_dir_ctxt(struct lmv_dir_ctxt *ctxt)
        int i;
 
        for (i = 0; i < ctxt->ldc_count; i++)
-               put_stripe_dirent(&ctxt->ldc_stripes[i]);
+               stripe_dirent_unload(&ctxt->ldc_stripes[i]);
 }
 
-static struct lu_dirent *stripe_dirent_next(struct lmv_dir_ctxt *ctxt,
+/* if @ent is dummy, or . .., get next */
+static struct lu_dirent *stripe_dirent_get(struct lmv_dir_ctxt *ctxt,
+                                          struct lu_dirent *ent,
+                                          int stripe_index)
+{
+       for (; ent; ent = lu_dirent_next(ent)) {
+               /* Skip dummy entry */
+               if (le16_to_cpu(ent->lde_namelen) == 0)
+                       continue;
+
+               /* skip . and .. for other stripes */
+               if (stripe_index &&
+                   (strncmp(ent->lde_name, ".",
+                            le16_to_cpu(ent->lde_namelen)) == 0 ||
+                    strncmp(ent->lde_name, "..",
+                            le16_to_cpu(ent->lde_namelen)) == 0))
+                       continue;
+
+               if (le64_to_cpu(ent->lde_hash) >= ctxt->ldc_hash)
+                       break;
+       }
+
+       return ent;
+}
+
+static struct lu_dirent *stripe_dirent_load(struct lmv_dir_ctxt *ctxt,
                                            struct stripe_dirent *stripe,
                                            int stripe_index)
 {
+       struct md_op_data *op_data = ctxt->ldc_op_data;
+       struct lmv_oinfo *oinfo;
+       struct lu_fid fid = op_data->op_fid1;
+       struct inode *inode = op_data->op_data;
+       struct lmv_tgt_desc *tgt;
        struct lu_dirent *ent = stripe->sd_ent;
        __u64 hash = ctxt->ldc_hash;
-       __u64 end;
        int rc = 0;
+
        ENTRY;
 
        LASSERT(stripe == &ctxt->ldc_stripes[stripe_index]);
-
-       if (stripe->sd_eof)
-               RETURN(NULL);
-
-       if (ent) {
-               ent = lu_dirent_next(ent);
-               if (!ent) {
-check_eof:
-                       end = le64_to_cpu(stripe->sd_dp->ldp_hash_end);
-                       LASSERTF(hash <= end, "hash %llx end %llx\n",
-                                hash, end);
+       LASSERT(!ent);
+
+       do {
+               if (stripe->sd_page) {
+                       __u64 end = le64_to_cpu(stripe->sd_dp->ldp_hash_end);
+
+                       /* @hash should be the last dirent hash */
+                       LASSERTF(hash <= end,
+                                "ctxt@%p stripe@%p hash %llx end %llx\n",
+                                ctxt, stripe, hash, end);
+                       /* unload last page */
+                       stripe_dirent_unload(stripe);
+                       /* eof */
                        if (end == MDS_DIR_END_OFF) {
-                               stripe->sd_ent = NULL;
                                stripe->sd_eof = true;
-                               RETURN(NULL);
+                               break;
                        }
-
-                       put_stripe_dirent(stripe);
                        hash = end;
                }
-       }
-
-       if (!ent) {
-               struct md_op_data *op_data = ctxt->ldc_op_data;
-               struct lmv_oinfo *oinfo;
-               struct lu_fid fid = op_data->op_fid1;
-               struct inode *inode = op_data->op_data;
-               struct lmv_tgt_desc *tgt;
-
-               LASSERT(!stripe->sd_page);
 
                oinfo = &op_data->op_mea1->lsm_md_oinfo[stripe_index];
                tgt = lmv_get_target(ctxt->ldc_lmv, oinfo->lmo_mds, NULL);
-               if (IS_ERR(tgt))
-                       GOTO(out, rc = PTR_ERR(tgt));
+               if (IS_ERR(tgt)) {
+                       rc = PTR_ERR(tgt);
+                       break;
+               }
 
-               /* op_data will be shared by each stripe, so we need
-                * reset these value for each stripe */
+               /* op_data is shared by stripes, reset after use */
                op_data->op_fid1 = oinfo->lmo_fid;
                op_data->op_fid2 = oinfo->lmo_fid;
                op_data->op_data = oinfo->lmo_root;
@@ -2133,45 +2153,26 @@ check_eof:
                op_data->op_data = inode;
 
                if (rc)
-                       GOTO(out, rc);
-
-               stripe->sd_dp = page_address(stripe->sd_page);
-               ent = lu_dirent_start(stripe->sd_dp);
-       }
-
-       for (; ent; ent = lu_dirent_next(ent)) {
-               /* Skip dummy entry */
-               if (le16_to_cpu(ent->lde_namelen) == 0)
-                       continue;
-
-               /* skip . and .. for other stripes */
-               if (stripe_index &&
-                   (strncmp(ent->lde_name, ".",
-                            le16_to_cpu(ent->lde_namelen)) == 0 ||
-                    strncmp(ent->lde_name, "..",
-                            le16_to_cpu(ent->lde_namelen)) == 0))
-                       continue;
-
-               if (le64_to_cpu(ent->lde_hash) >= hash)
                        break;
-       }
 
-       if (!ent)
-               goto check_eof;
-       EXIT;
+               stripe->sd_dp = page_address(stripe->sd_page);
+               ent = stripe_dirent_get(ctxt, lu_dirent_start(stripe->sd_dp),
+                                       stripe_index);
+               /* in case a page filled with ., .. and dummy, read next */
+       } while (!ent);
 
-out:
        stripe->sd_ent = ent;
-       /* treat error as eof, so dir can be partially accessed */
        if (rc) {
-               put_stripe_dirent(stripe);
+               LASSERT(!ent);
+               /* treat error as eof, so dir can be partially accessed */
                stripe->sd_eof = true;
                LCONSOLE_WARN("dir "DFID" stripe %d readdir failed: %d, "
                              "directory is partially accessed!\n",
                              PFID(&ctxt->ldc_op_data->op_fid1), stripe_index,
                              rc);
        }
-       return ent;
+
+       RETURN(ent);
 }
 
 static int lmv_file_resync(struct obd_export *exp, struct md_op_data *data)
@@ -2224,8 +2225,7 @@ static struct lu_dirent *lmv_dirent_next(struct lmv_dir_ctxt *ctxt)
                        continue;
 
                if (!stripe->sd_ent) {
-                       /* locate starting entry */
-                       stripe_dirent_next(ctxt, stripe, i);
+                       stripe_dirent_load(ctxt, stripe, i);
                        if (!stripe->sd_ent) {
                                LASSERT(stripe->sd_eof);
                                continue;
@@ -2246,7 +2246,8 @@ static struct lu_dirent *lmv_dirent_next(struct lmv_dir_ctxt *ctxt)
                stripe = &ctxt->ldc_stripes[min];
                ent = stripe->sd_ent;
                /* pop found dirent */
-               stripe_dirent_next(ctxt, stripe, min);
+               stripe->sd_ent = stripe_dirent_get(ctxt, lu_dirent_next(ent),
+                                                  min);
        }
 
        return ent;