exofs: groups support
* _calc_stripe_info() changes to accommodate for grouping
calculations. Returns additional information
* old _prepare_pages() becomes _prepare_one_group()
which stores pages belonging to one device group.
* New _prepare_for_striping iterates on all groups calling
_prepare_one_group().
* Enable mounting of groups data_maps (group_width != 0)
[QUESTION]
what is faster A or B;
A. x += stride;
x = x % width + first_x;
B x += stride
if (x < last_x)
x = first_x;
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
diff --git a/fs/exofs/super.c b/fs/exofs/super.c
index 8f4e4b3..6cf5e4e 100644
--- a/fs/exofs/super.c
+++ b/fs/exofs/super.c
@@ -323,11 +323,7 @@
sbi->data_map.odm_raid_algorithm =
le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
-/* FIXME: Only raid0 !group_width/depth for now. if not so, do not mount */
- if (sbi->data_map.odm_group_width || sbi->data_map.odm_group_depth) {
- EXOFS_ERR("Group width/depth not supported\n");
- return -EINVAL;
- }
+/* 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);
@@ -343,14 +339,6 @@
return -EINVAL;
}
- stripe_length = sbi->data_map.odm_stripe_unit *
- (numdevs / (sbi->data_map.odm_mirror_cnt + 1));
- if (stripe_length >= (1ULL << 32)) {
- EXOFS_ERR("Total Stripe length(0x%llx)"
- " >= 32bit is not supported\n", _LLU(stripe_length));
- return -EINVAL;
- }
-
if (0 != (sbi->data_map.odm_stripe_unit & ~PAGE_MASK)) {
EXOFS_ERR("Stripe Unit(0x%llx)"
" must be Multples of PAGE_SIZE(0x%lx)\n",
@@ -360,8 +348,36 @@
sbi->layout.stripe_unit = sbi->data_map.odm_stripe_unit;
sbi->layout.mirrors_p1 = sbi->data_map.odm_mirror_cnt + 1;
- sbi->layout.group_width = sbi->data_map.odm_num_comps /
+
+ 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_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;
+ } else {
+ if (sbi->data_map.odm_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;
+ }
+ sbi->layout.group_width = sbi->data_map.odm_num_comps /
sbi->layout.mirrors_p1;
+ sbi->layout.group_depth = -1;
+ sbi->layout.group_count = 1;
+ }
+
+ stripe_length = (u64)sbi->layout.group_width * sbi->layout.stripe_unit;
+ if (stripe_length >= (1ULL << 32)) {
+ EXOFS_ERR("Total Stripe length(0x%llx)"
+ " >= 32bit is not supported\n", _LLU(stripe_length));
+ return -EINVAL;
+ }
return 0;
}
@@ -540,6 +556,8 @@
sbi->layout.stripe_unit = PAGE_SIZE;
sbi->layout.mirrors_p1 = 1;
sbi->layout.group_width = 1;
+ sbi->layout.group_depth = -1;
+ sbi->layout.group_count = 1;
sbi->layout.s_ods[0] = od;
sbi->layout.s_numdevs = 1;
sbi->layout.s_pid = opts->pid;