dm raid: move sectors_per_dev calculation

In preparation for RAID10 inclusion in dm-raid, we move the sectors_per_dev
calculation later in the device creation process.  This is because we won't
know up-front how many stripes vs how many mirrors there are which will
change the calculation.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 1717ed3..f4275a8 100644 (file)
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -101,20 +101,12 @@ static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *ra
 {
        unsigned i;
        struct raid_set *rs;
-       sector_t sectors_per_dev;
 
        if (raid_devs <= raid_type->parity_devs) {
                ti->error = "Insufficient number of devices";
                return ERR_PTR(-EINVAL);
        }
 
-       sectors_per_dev = ti->len;
-       if ((raid_type->level > 1) &&
-           sector_div(sectors_per_dev, (raid_devs - raid_type->parity_devs))) {
-               ti->error = "Target length not divisible by number of data devices";
-               return ERR_PTR(-EINVAL);
-       }
-
        rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL);
        if (!rs) {
                ti->error = "Cannot allocate raid context";
@@ -128,7 +120,6 @@ static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *ra
        rs->md.raid_disks = raid_devs;
        rs->md.level = raid_type->level;
        rs->md.new_level = rs->md.level;
-       rs->md.dev_sectors = sectors_per_dev;
        rs->md.layout = raid_type->algorithm;
        rs->md.new_layout = rs->md.layout;
        rs->md.delta_disks = 0;
@@ -143,6 +134,7 @@ static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *ra
         *  rs->md.external
         *  rs->md.chunk_sectors
         *  rs->md.new_chunk_sectors
+        *  rs->md.dev_sectors
         */
 
        return rs;
@@ -353,6 +345,7 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
 {
        unsigned i, rebuild_cnt = 0;
        unsigned long value, region_size = 0;
+       sector_t sectors_per_dev = rs->ti->len;
        sector_t max_io_len;
        char *key;
 
@@ -545,6 +538,13 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
        if (dm_set_target_max_io_len(rs->ti, max_io_len))
                return -EINVAL;
 
+       if ((rs->raid_type->level > 1) &&
+           sector_div(sectors_per_dev, (rs->md.raid_disks - rs->raid_type->parity_devs))) {
+               rs->ti->error = "Target length not divisible by number of data devices";
+               return -EINVAL;
+       }
+       rs->md.dev_sectors = sectors_per_dev;
+
        /* Assume there are no metadata devices until the drives are parsed */
        rs->md.persistent = 0;
        rs->md.external = 1;