LU-3531 mdc: release dir page cache after accessing

[fs/lustre-release.git] / lustre / mdc / mdc_request.c

diff --git a/lustre/mdc/mdc_request.c b/lustre/mdc/mdc_request.c
index fcc2217..e111015 100644 (file)
--- a/lustre/mdc/mdc_request.c
+++ b/lustre/mdc/mdc_request.c
@@ -1185,7 +1185,6 @@ restart_bulk:
 #ifdef __KERNEL__
 static void mdc_release_page(struct page *page, int remove)
 {
-       kunmap(page);
        if (remove) {
                lock_page(page);
                if (likely(page->mapping != NULL))
@@ -1239,6 +1238,7 @@ static struct page *mdc_page_locate(struct address_space *mapping, __u64 *hash,
                        CDEBUG(D_VFSTRACE, "page%lu [%llu %llu], hash"LPU64"\n",
                               offset, *start, *end, *hash);
                        if (*hash > *end) {
+                               kunmap(page);
                                mdc_release_page(page, 0);
                                page = NULL;
                        } else if (*end != *start && *hash == *end) {
@@ -1248,6 +1248,7 @@ static struct page *mdc_page_locate(struct address_space *mapping, __u64 *hash,
                                 * ll_get_dir_page() will issue RPC to fetch
                                 * the page we want.
                                 */
+                               kunmap(page);
                                mdc_release_page(page,
                                    le32_to_cpu(dp->ldp_flags) & LDF_COLLIDE);
                                page = NULL;
@@ -1637,37 +1638,38 @@ fail:
  * Read one directory entry from the cache.
  */
 int mdc_read_entry(struct obd_export *exp, struct md_op_data *op_data,
-                  struct md_callback *cb_op, struct lu_dirent **entp)
+                  struct md_callback *cb_op, struct lu_dirent **entp,
+                  struct page **ppage)
 {
        struct page             *page = NULL;
        struct lu_dirpage       *dp;
        struct lu_dirent        *ent;
        int                     rc = 0;
-       int                     index = 0;
        ENTRY;
 
-       if (op_data->op_hash_offset == MDS_DIR_END_OFF) {
-               *entp = NULL;
+       CDEBUG(D_INFO, DFID "offset = "LPU64"\n", PFID(&op_data->op_fid1),
+              op_data->op_hash_offset);
+
+       *ppage = NULL;
+       *entp = NULL;
+
+       if (op_data->op_hash_offset == MDS_DIR_END_OFF)
                RETURN(0);
-       }
 
        rc = mdc_read_page(exp, op_data, cb_op, &page);
        if (rc != 0)
                RETURN(rc);
 
-       if (op_data->op_cli_flags & CLI_READENT_END) {
-               mdc_release_page(page, 0);
-               RETURN(0);
-       }
-
-       dp = kmap(page);
+       dp = page_address(page);
        for (ent = lu_dirent_start(dp); ent != NULL;
             ent = lu_dirent_next(ent)) {
-               index++;
-               if (ent->lde_hash > op_data->op_hash_offset)
+               /* Skip dummy entry */
+               if (le16_to_cpu(ent->lde_namelen) == 0)
+                       continue;
+
+               if (le64_to_cpu(ent->lde_hash) > op_data->op_hash_offset)
                        break;
        }
-       kunmap(page);
 
        /* If it can not find entry in current page, try next page. */
        if (ent == NULL) {
@@ -1686,14 +1688,14 @@ int mdc_read_entry(struct obd_export *exp, struct md_op_data *op_data,
                        RETURN(rc);
 
                if (page != NULL) {
-                       dp = kmap(page);
+                       dp = page_address(page);
                        ent = lu_dirent_start(dp);
-                       kunmap(page);
                }
 
                op_data->op_hash_offset = orig_offset;
        }
 
+       *ppage = page;
        *entp = ent;
 
        RETURN(rc);
@@ -1746,7 +1748,8 @@ static int mdc_read_page(struct obd_export *exp, struct md_op_data *op_data,
 }
 
 int mdc_read_entry(struct obd_export *exp, struct md_op_data *op_data,
-                  struct md_callback *cb_op, struct lu_dirent **entp)
+                  struct md_callback *cb_op, struct lu_dirent **entp,
+                  struct page **ppage)
 {
        struct page             *page = NULL;
        struct lu_dirpage       *dp;