md/raid10: split out interpretation of layout to separate function.
authorNeilBrown <neilb@suse.de>
Sun, 20 May 2012 23:28:33 +0000 (09:28 +1000)
committerNeilBrown <neilb@suse.de>
Sun, 20 May 2012 23:28:33 +0000 (09:28 +1000)
We will soon be interpreting the layout (and chunksize etc) from
multiple places to support reshape.  So split it out into separate
function.

Signed-off-by: NeilBrown <neilb@suse.de>
drivers/md/raid10.c

index 1c90005ab343c34f9ab7f4ae1e89b9fdf337846c..f102e88fc7854a8231aac909fdb37b8479910429 100644 (file)
@@ -3253,26 +3253,64 @@ static void calc_sectors(struct r10conf *conf, sector_t size)
        }
 }
 
+enum geo_type {geo_new, geo_old, geo_start};
+static int setup_geo(struct geom *geo, struct mddev *mddev, enum geo_type new)
+{
+       int nc, fc, fo;
+       int layout, chunk, disks;
+       switch (new) {
+       case geo_old:
+               layout = mddev->layout;
+               chunk = mddev->chunk_sectors;
+               disks = mddev->raid_disks - mddev->delta_disks;
+               break;
+       case geo_new:
+               layout = mddev->new_layout;
+               chunk = mddev->new_chunk_sectors;
+               disks = mddev->raid_disks;
+               break;
+       default: /* avoid 'may be unused' warnings */
+       case geo_start: /* new when starting reshape - raid_disks not
+                        * updated yet. */
+               layout = mddev->new_layout;
+               chunk = mddev->new_chunk_sectors;
+               disks = mddev->raid_disks + mddev->delta_disks;
+               break;
+       }
+       if (layout >> 17)
+               return -1;
+       if (chunk < (PAGE_SIZE >> 9) ||
+           !is_power_of_2(chunk))
+               return -2;
+       nc = layout & 255;
+       fc = (layout >> 8) & 255;
+       fo = layout & (1<<16);
+       geo->raid_disks = disks;
+       geo->near_copies = nc;
+       geo->far_copies = fc;
+       geo->far_offset = fo;
+       geo->chunk_mask = chunk - 1;
+       geo->chunk_shift = ffz(~chunk);
+       return nc*fc;
+}
+
 static struct r10conf *setup_conf(struct mddev *mddev)
 {
        struct r10conf *conf = NULL;
-       int nc, fc, fo;
        int err = -EINVAL;
+       struct geom geo;
+       int copies;
+
+       copies = setup_geo(&geo, mddev, geo_new);
 
-       if (mddev->new_chunk_sectors < (PAGE_SIZE >> 9) ||
-           !is_power_of_2(mddev->new_chunk_sectors)) {
+       if (copies == -2) {
                printk(KERN_ERR "md/raid10:%s: chunk size must be "
                       "at least PAGE_SIZE(%ld) and be a power of 2.\n",
                       mdname(mddev), PAGE_SIZE);
                goto out;
        }
 
-       nc = mddev->new_layout & 255;
-       fc = (mddev->new_layout >> 8) & 255;
-       fo = mddev->new_layout & (1<<16);
-
-       if ((nc*fc) <2 || (nc*fc) > mddev->raid_disks ||
-           (mddev->new_layout >> 17)) {
+       if (copies < 2 || copies > mddev->raid_disks) {
                printk(KERN_ERR "md/raid10:%s: unsupported raid10 layout: 0x%8x\n",
                       mdname(mddev), mddev->new_layout);
                goto out;
@@ -3292,15 +3330,8 @@ static struct r10conf *setup_conf(struct mddev *mddev)
        if (!conf->tmppage)
                goto out;
 
-
-       conf->geo.raid_disks = mddev->raid_disks;
-       conf->geo.near_copies = nc;
-       conf->geo.far_copies = fc;
-       conf->copies = nc*fc;
-       conf->geo.far_offset = fo;
-       conf->geo.chunk_mask = mddev->new_chunk_sectors - 1;
-       conf->geo.chunk_shift = ffz(~mddev->new_chunk_sectors);
-
+       conf->geo = geo;
+       conf->copies = copies;
        conf->r10bio_pool = mempool_create(NR_RAID10_BIOS, r10bio_pool_alloc,
                                           r10bio_pool_free, conf);
        if (!conf->r10bio_pool)