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) {
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 8bdc9bf..e379479 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -2028,8 +2028,9 @@
int nc, fc, fo;
sector_t stride, size;
- if (mddev->chunk_size == 0) {
- printk(KERN_ERR "md/raid10: non-zero chunk size required.\n");
+ if (mddev->chunk_size < PAGE_SIZE) {
+ printk(KERN_ERR "md/raid10: chunk size must be "
+ "at least PAGE_SIZE(%ld).\n", PAGE_SIZE);
return -EINVAL;
}
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index d72be4b..a36a743 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -4007,6 +4007,13 @@
return -EIO;
}
+ if (mddev->chunk_size < PAGE_SIZE) {
+ printk(KERN_ERR "md/raid5: chunk_size must be at least "
+ "PAGE_SIZE but %d < %ld\n",
+ mddev->chunk_size, PAGE_SIZE);
+ return -EINVAL;
+ }
+
if (mddev->reshape_position != MaxSector) {
/* Check that we can continue the reshape.
* Currently only disks can change, it must