From: raz ben yehuda <raziebe@gmail.com>
Date: Tue, 16 Jun 2009 07:01:42 +0000 (+1000)
Subject: md: prepare for non-power-of-two chunk sizes
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2ac06c3332898103210b478c5a17c20e28929287;p=mv-sheeva.git

md: prepare for non-power-of-two chunk sizes

Remove chunk size check from md as this is now performed in the run
function in each personality.

Replace chunk size power 2 code calculations by a regular division.

Signed-off-by: raziebe@gmail.com
Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 20f6ac33834..a02bde70874 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -444,8 +444,11 @@ static sector_t calc_num_sectors(mdk_rdev_t *rdev, unsigned chunk_size)
 {
 	sector_t num_sectors = rdev->sb_start;
 
-	if (chunk_size)
-		num_sectors &= ~((sector_t)chunk_size/512 - 1);
+	if (chunk_size) {
+		unsigned chunk_sects = chunk_size>>9;
+		sector_div(num_sectors, chunk_sects);
+		num_sectors *= chunk_sects;
+	}
 	return num_sectors;
 }
 
@@ -1248,8 +1251,12 @@ static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 	if (rdev->sectors < le64_to_cpu(sb->data_size))
 		return -EINVAL;
 	rdev->sectors = le64_to_cpu(sb->data_size);
-	if (le32_to_cpu(sb->chunksize))
-		rdev->sectors &= ~((sector_t)le32_to_cpu(sb->chunksize) - 1);
+	if (le32_to_cpu(sb->chunksize)) {
+		int chunk_sects = le32_to_cpu(sb->chunksize);
+		sector_t chunks = rdev->sectors;
+		sector_div(chunks, chunk_sects);
+		rdev->sectors = chunks * chunk_sects;
+	}
 
 	if (le64_to_cpu(sb->size) > rdev->sectors)
 		return -EINVAL;
@@ -3528,7 +3535,8 @@ min_sync_store(mddev_t *mddev, const char *buf, size_t len)
 
 	/* Must be a multiple of chunk_size */
 	if (mddev->chunk_size) {
-		if (min & (sector_t)((mddev->chunk_size>>9)-1))
+		sector_t temp = min;
+		if (sector_div(temp, (mddev->chunk_size>>9)))
 			return -EINVAL;
 	}
 	mddev->resync_min = min;
@@ -3565,7 +3573,8 @@ max_sync_store(mddev_t *mddev, const char *buf, size_t len)
 
 		/* Must be a multiple of chunk_size */
 		if (mddev->chunk_size) {
-			if (max & (sector_t)((mddev->chunk_size>>9)-1))
+			sector_t temp = max;
+			if (sector_div(temp, (mddev->chunk_size>>9)))
 				return -EINVAL;
 		}
 		mddev->resync_max = max;
@@ -4006,14 +4015,6 @@ static int do_md_run(mddev_t * mddev)
 				chunk_size, MAX_CHUNK_SIZE);
 			return -EINVAL;
 		}
-		/*
-		 * chunk-size has to be a power of 2
-		 */
-		if ( (1 << ffz(~chunk_size)) != chunk_size) {
-			printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
-			return -EINVAL;
-		}
-
 		/* devices must have minimum size of one chunk */
 		list_for_each_entry(rdev, &mddev->disks, same_set) {
 			if (test_bit(Faulty, &rdev->flags))