LU-14337 lov: return stripe_count=1 instead of 0 for DoM files

[fs/lustre-release.git] / lustre / lov / lov_pack.c

diff --git a/lustre/lov/lov_pack.c b/lustre/lov/lov_pack.c
index 23ffe6c..528f067 100644 (file)
--- a/lustre/lov/lov_pack.c
+++ b/lustre/lov/lov_pack.c
@@ -90,34 +90,6 @@ void lov_dump_lmm_v1(int level, struct lov_mds_md_v1 *lmm)
                             le16_to_cpu(lmm->lmm_stripe_count));
 }
 
-void lov_dump_lmm_v3(int level, struct lov_mds_md_v3 *lmm)
-{
-       lov_dump_lmm_common(level, lmm);
-       CDEBUG_LIMIT(level, "pool_name "LOV_POOLNAMEF"\n", lmm->lmm_pool_name);
-       lov_dump_lmm_objects(level, lmm->lmm_objects,
-                            le16_to_cpu(lmm->lmm_stripe_count));
-}
-
-void lov_dump_lmm(int level, void *lmm)
-{
-       int magic;
-
-       magic = le32_to_cpu(((struct lov_mds_md *)lmm)->lmm_magic);
-       switch (magic) {
-       case LOV_MAGIC_V1:
-               lov_dump_lmm_v1(level, (struct lov_mds_md_v1 *)lmm);
-               break;
-       case LOV_MAGIC_V3:
-               lov_dump_lmm_v3(level, (struct lov_mds_md_v3 *)lmm);
-               break;
-       default:
-               CDEBUG_LIMIT(level, "unrecognized lmm_magic %x, assuming %x\n",
-                            magic, LOV_MAGIC_V1);
-               lov_dump_lmm_common(level, lmm);
-               break;
-       }
-}
-
 /**
  * Pack LOV striping metadata for disk storage format (in little
  * endian byte order).
@@ -126,8 +98,8 @@ void lov_dump_lmm(int level, void *lmm)
  * then return the size needed. If \a buf_size is too small then
  * return -ERANGE. Otherwise return the size of the result.
  */
-ssize_t lov_lsm_pack_v1v3(const struct lov_stripe_md *lsm, void *buf,
-                         size_t buf_size)
+static ssize_t lov_lsm_pack_v1v3(const struct lov_stripe_md *lsm, void *buf,
+                                size_t buf_size)
 {
        struct lov_mds_md_v1 *lmmv1 = buf;
        struct lov_mds_md_v3 *lmmv3 = buf;
@@ -159,8 +131,8 @@ ssize_t lov_lsm_pack_v1v3(const struct lov_stripe_md *lsm, void *buf,
        lmmv1->lmm_layout_gen = cpu_to_le16(lsm->lsm_layout_gen);
 
        if (lsm->lsm_magic == LOV_MAGIC_V3) {
-               CLASSERT(sizeof(lsm->lsm_entries[0]->lsme_pool_name) ==
-                        sizeof(lmmv3->lmm_pool_name));
+               BUILD_BUG_ON(sizeof(lsm->lsm_entries[0]->lsme_pool_name) !=
+                                   sizeof(lmmv3->lmm_pool_name));
                strlcpy(lmmv3->lmm_pool_name,
                        lsm->lsm_entries[0]->lsme_pool_name,
                        sizeof(lmmv3->lmm_pool_name));
@@ -183,8 +155,8 @@ ssize_t lov_lsm_pack_v1v3(const struct lov_stripe_md *lsm, void *buf,
        RETURN(lmm_size);
 }
 
-ssize_t lov_lsm_pack_foreign(const struct lov_stripe_md *lsm, void *buf,
-                            size_t buf_size)
+static ssize_t lov_lsm_pack_foreign(const struct lov_stripe_md *lsm, void *buf,
+                                   size_t buf_size)
 {
        struct lov_foreign_md *lfm = buf;
        size_t lfm_size;
@@ -389,8 +361,8 @@ int lov_getstripe(const struct lu_env *env, struct lov_object *obj,
        struct lov_mds_md *lmmk, *lmm;
        struct lov_foreign_md *lfm;
        struct lov_user_md_v1 lum;
-       size_t lmmk_size;
-       ssize_t lmm_size, lum_size = 0;
+       size_t lmmk_size, lum_size = 0;
+       ssize_t lmm_size;
        static bool printed;
        int rc = 0;
 
@@ -488,14 +460,23 @@ int lov_getstripe(const struct lu_env *env, struct lov_object *obj,
                                i--;
                        comp_md = (struct lov_mds_md *)((char *)comp_v1 +
                                        comp_v1->lcm_entries[i].lcme_offset);
+                       lum_size = comp_v1->lcm_entries[i].lcme_size;
                }
 
                lmm = comp_md;
-               lmm_size = lum_size;
+               lmm_size = min(lum_size, lmmk_size);
        } else {
                lmm = lmmk;
                lmm_size = lmmk_size;
        }
+
+       /**
+        * Return stripe_count=1 instead of 0 for DoM files to avoid
+        * divide-by-zero for older userspace that calls this ioctl,
+        * e.g. lustre ADIO driver.
+        */
+       if ((lum.lmm_stripe_count == 0) && (lum.lmm_pattern & LOV_PATTERN_MDT))
+               lum.lmm_stripe_count = 1;
        /**
         * User specified limited buffer size, usually the buffer is
         * from ll_lov_setstripe(), and the buffer can only hold basic