md: Relax minimum size restrictions on chunk_size.
Currently, the 'chunk_size' of an array must be at-least PAGE_SIZE.
This makes moving an array to a machine with a larger PAGE_SIZE, or
changing the kernel to use a larger PAGE_SIZE, can stop an array from
working.
For RAID10 and RAID4/5/6, this is non-trivial to fix as the resync
process works on whole pages at a time, and assumes them to be wholly
within a stripe. For other raid personalities, this restriction is
not needed at all and can be dropped.
So remove the test on chunk_size from common can, and add it in just
the places where it is needed: raid10 and raid4/5/6.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index a29187d..be2014f 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3520,17 +3520,12 @@
return -EINVAL;
}
/*
- * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
+ * 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;
}
- if (chunk_size < PAGE_SIZE) {
- printk(KERN_ERR "too small chunk_size: %d < %ld\n",
- chunk_size, PAGE_SIZE);
- return -EINVAL;
- }
/* devices must have minimum size of one chunk */
rdev_for_each(rdev, tmp, mddev) {