exofs: Remove unused data_map member from exofs_sb_info

The struct pnfs_osd_data_map data_map member of exofs_sb_info was
never used after mount. In fact all it's members were duplicated
by the ore_layout structure. So just remove the duplicated information.

Also removed some stupid, but perfectly supported, restrictions on
layout parameters. The case where num_devices is not divisible by
mirror_count+1 is perfectly fine since the rotating device view
will eventually use all the devices it can get.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>

2 files changed, 22 insertions, 38 deletions

diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h
index c09d5a765efe..3b2e0478f363 100644
--- a/fs/exofs/exofs.h
+++ b/fs/exofs/exofs.h
@@ -66,9 +66,6 @@ struct exofs_sb_info {
         u32             s_next_generation;      /* next gen # to use          */
         atomic_t        s_curr_pending;         /* number of pending commands */
 
-        struct pnfs_osd_data_map data_map;      /* Default raid to use
-                                                 * FIXME: Needed ?
-                                                 */
         struct ore_layout       layout;         /* Default files layout       */
         struct ore_comp one_comp;               /* id & cred of partition id=0*/
         struct ore_components oc;               /* comps for the partition    */
diff --git a/fs/exofs/super.c b/fs/exofs/super.c
index babb1958f6f0..90b4c526939f 100644
--- a/fs/exofs/super.c
+++ b/fs/exofs/super.c
@@ -481,64 +481,51 @@ static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 {
         u64 stripe_length;
 
-        sbi->data_map.odm_num_comps   =
-                                le32_to_cpu(dt->dt_data_map.cb_num_comps);
-        sbi->data_map.odm_stripe_unit =
+        sbi->layout.stripe_unit =
                                 le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
-        sbi->data_map.odm_group_width =
+        sbi->layout.group_width =
                                 le32_to_cpu(dt->dt_data_map.cb_group_width);
-        sbi->data_map.odm_group_depth =
+        sbi->layout.group_depth =
                                 le32_to_cpu(dt->dt_data_map.cb_group_depth);
-        sbi->data_map.odm_mirror_cnt  =
-                                le32_to_cpu(dt->dt_data_map.cb_mirror_cnt);
-        sbi->data_map.odm_raid_algorithm  =
+        sbi->layout.mirrors_p1  =
+                                le32_to_cpu(dt->dt_data_map.cb_mirror_cnt) + 1;
+        sbi->layout.raid_algorithm  =
                                 le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
 
 /* FIXME: Only raid0 for now. if not so, do not mount */
-        if (sbi->data_map.odm_num_comps != numdevs) {
-                EXOFS_ERR("odm_num_comps(%u) != numdevs(%u)\n",
-                          sbi->data_map.odm_num_comps, numdevs);
-                return -EINVAL;
-        }
-        if (sbi->data_map.odm_raid_algorithm != PNFS_OSD_RAID_0) {
+        if (sbi->layout.raid_algorithm != PNFS_OSD_RAID_0) {
                 EXOFS_ERR("Only RAID_0 for now\n");
                 return -EINVAL;
         }
-        if (0 != (numdevs % (sbi->data_map.odm_mirror_cnt + 1))) {
-                EXOFS_ERR("Data Map wrong, numdevs=%d mirrors=%d\n",
-                          numdevs, sbi->data_map.odm_mirror_cnt);
+        if (numdevs < (sbi->layout.group_width * sbi->layout.mirrors_p1)) {
+                EXOFS_ERR("Data Map wrong, "
+                          "numdevs=%d < group_width=%d * mirrors=%d\n",
+                          numdevs, sbi->layout.group_width,
+                          sbi->layout.mirrors_p1);
                 return -EINVAL;
         }
 
-        if (0 != (sbi->data_map.odm_stripe_unit & ~PAGE_MASK)) {
+        if (0 != (sbi->layout.stripe_unit & ~PAGE_MASK)) {
                 EXOFS_ERR("Stripe Unit(0x%llx)"
                           " must be Multples of PAGE_SIZE(0x%lx)\n",
-                          _LLU(sbi->data_map.odm_stripe_unit), PAGE_SIZE);
+                          _LLU(sbi->layout.stripe_unit), PAGE_SIZE);
                 return -EINVAL;
         }
 
-        sbi->layout.stripe_unit = sbi->data_map.odm_stripe_unit;
-        sbi->layout.mirrors_p1 = sbi->data_map.odm_mirror_cnt + 1;
-
-        if (sbi->data_map.odm_group_width) {
-                sbi->layout.group_width = sbi->data_map.odm_group_width;
-                sbi->layout.group_depth = sbi->data_map.odm_group_depth;
+        if (sbi->layout.group_width) {
                 if (!sbi->layout.group_depth) {
                         EXOFS_ERR("group_depth == 0 && group_width != 0\n");
                         return -EINVAL;
                 }
-                sbi->layout.group_count = sbi->data_map.odm_num_comps /
-                                                sbi->layout.mirrors_p1 /
-                                                sbi->data_map.odm_group_width;
+                sbi->layout.group_count = numdevs / sbi->layout.mirrors_p1 /
+                                                sbi->layout.group_width;
         } else {
-                if (sbi->data_map.odm_group_depth) {
+                if (sbi->layout.group_depth) {
                         printk(KERN_NOTICE "Warning: group_depth ignored "
-                                "group_width == 0 && group_depth == %d\n",
-                                sbi->data_map.odm_group_depth);
-                        sbi->data_map.odm_group_depth = 0;
+                                "group_width == 0 && group_depth == %lld\n",
+                                _LLU(sbi->layout.group_depth));
                 }
-                sbi->layout.group_width = sbi->data_map.odm_num_comps /
-                                                        sbi->layout.mirrors_p1;
+                sbi->layout.group_width = numdevs / sbi->layout.mirrors_p1;
                 sbi->layout.group_depth = -1;
                 sbi->layout.group_count = 1;
         }
@@ -558,7 +545,7 @@ static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
                 sbi->layout.group_width,
                 _LLU(sbi->layout.group_depth),
                 sbi->layout.mirrors_p1,
-                sbi->data_map.odm_raid_algorithm);
+                sbi->layout.raid_algorithm);
         return 0;
 }