From 2ae600cd15a7cce7f2c26d24cfbd9c1bc9e1810d Mon Sep 17 00:00:00 2001
From: Heinz Mauelshagen <heinzm@redhat.com>
Date: Thu, 1 Feb 2018 19:06:09 +0100
Subject: [PATCH] dm unstripe: support non-power-of-2 chunk size
Git-commit: 2ae600cd15a7cce7f2c26d24cfbd9c1bc9e1810d
References: bsc#1111974
Patch-mainline: v4.17-rc1
Address "FIXME: must support non power of 2 chunk_size, dm-stripe.c does".
Bump target version to indicate change.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Tested-by: Scott Bauer <Scott.Bauer@intel.com>
Reviewed-by: Scott Bauer <Scott.Bauer@intel.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Coly Li <colyli@suse.de>
---
drivers/md/dm-unstripe.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/drivers/md/dm-unstripe.c b/drivers/md/dm-unstripe.c
index 65f838fa2e99..05d76f337838 100644
--- a/drivers/md/dm-unstripe.c
+++ b/drivers/md/dm-unstripe.c
@@ -69,12 +69,6 @@ static int unstripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
goto err;
}
- // FIXME: must support non power of 2 chunk_size, dm-stripe.c does
- if (!is_power_of_2(uc->chunk_size)) {
- ti->error = "Non power of 2 chunk_size is not supported yet";
- goto err;
- }
-
if (kstrtouint(argv[2], 10, &uc->unstripe)) {
ti->error = "Invalid stripe number";
goto err;
@@ -98,7 +92,7 @@ static int unstripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
uc->unstripe_offset = uc->unstripe * uc->chunk_size;
uc->unstripe_width = (uc->stripes - 1) * uc->chunk_size;
- uc->chunk_shift = fls(uc->chunk_size) - 1;
+ uc->chunk_shift = is_power_of_2(uc->chunk_size) ? fls(uc->chunk_size) - 1 : 0;
tmp_len = ti->len;
if (sector_div(tmp_len, uc->chunk_size)) {
@@ -129,14 +123,18 @@ static sector_t map_to_core(struct dm_target *ti, struct bio *bio)
{
struct unstripe_c *uc = ti->private;
sector_t sector = bio->bi_iter.bi_sector;
+ sector_t tmp_sector = sector;
/* Shift us up to the right "row" on the stripe */
- sector += uc->unstripe_width * (sector >> uc->chunk_shift);
+ if (uc->chunk_shift)
+ tmp_sector >>= uc->chunk_shift;
+ else
+ sector_div(tmp_sector, uc->chunk_size);
- /* Account for what stripe we're operating on */
- sector += uc->unstripe_offset;
+ sector += uc->unstripe_width * tmp_sector;
- return sector;
+ /* Account for what stripe we're operating on */
+ return sector + uc->unstripe_offset;
}
static int unstripe_map(struct dm_target *ti, struct bio *bio)
@@ -185,7 +183,7 @@ static void unstripe_io_hints(struct dm_target *ti,
static struct target_type unstripe_target = {
.name = "unstriped",
- .version = {1, 0, 0},
+ .version = {1, 1, 0},
.module = THIS_MODULE,
.ctr = unstripe_ctr,
.dtr = unstripe_dtr,
--
2.19.0