LU-3531 mdc: release dir page cache after accessing

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

diff --git a/lustre/lmv/lmv_obd.c b/lustre/lmv/lmv_obd.c
index 2d24c6e..e0941c9 100644 (file)
--- a/lustre/lmv/lmv_obd.c
+++ b/lustre/lmv/lmv_obd.c
@@ -2288,7 +2288,8 @@ static void lmv_adjust_dirpages(struct page **pages, int ncfspgs, int nlupgs)
 
 #define NORMAL_MAX_STRIPES 4
 int lmv_read_entry(struct obd_export *exp, struct md_op_data *op_data,
-                  struct md_callback *cb_op, struct lu_dirent **ldp)
+                  struct md_callback *cb_op, struct lu_dirent **ldp,
+                  struct page **ppage)
 {
        struct obd_device       *obd = exp->exp_obd;
        struct lmv_obd          *lmv = &obd->u.lmv;
@@ -2298,6 +2299,7 @@ int lmv_read_entry(struct obd_export *exp, struct md_op_data *op_data,
        int                     stripe_count;
        __u64                   min_hash;
        int                     min_idx = 0;
+       struct page             *min_page = NULL;
        int                     i;
        int                     rc;
        ENTRY;
@@ -2323,6 +2325,7 @@ int lmv_read_entry(struct obd_export *exp, struct md_op_data *op_data,
        min_hash = MDS_DIR_END_OFF;
        for (i = 0; i < stripe_count; i++) {
                struct lmv_tgt_desc *tgt;
+               struct page *page = NULL;
 
                if (likely(lsm == NULL)) {
                        tgt = lmv_find_target(lmv, &op_data->op_fid1);
@@ -2338,12 +2341,16 @@ int lmv_read_entry(struct obd_export *exp, struct md_op_data *op_data,
                        op_data->op_stripe_offset = i;
                }
 
-               rc = md_read_entry(tgt->ltd_exp, op_data, cb_op, &ents[i]);
+               rc = md_read_entry(tgt->ltd_exp, op_data, cb_op, &ents[i],
+                                  &page);
                if (rc != 0)
                        GOTO(out, rc);
 
                if (ents[i] != NULL &&
                    le64_to_cpu(ents[i]->lde_hash) <= min_hash) {
+                       if (min_page != NULL)
+                               page_cache_release(min_page);
+                       min_page = page;
                        min_hash = le64_to_cpu(ents[i]->lde_hash);
                        min_idx = i;
                }
@@ -2357,6 +2364,13 @@ out:
        if (stripe_count > NORMAL_MAX_STRIPES && ents != NULL)
                OBD_FREE(ents, sizeof(ents[0]) * stripe_count);
 
+       if (rc != 0 && min_page != NULL) {
+               kunmap(min_page);
+               page_cache_release(min_page);
+       } else {
+               *ppage = min_page;
+       }
+
        RETURN(rc);
 }