From b522adcde9c4d3fb7b579cfa9160d8bde7744be8 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 31 Mar 2009 15:00:31 +1100 Subject: md: 'array_size' sysfs attribute Allow userspace to set the size of the array according to the following semantics: 1/ size must be <= to the size returned by mddev->pers->size(mddev, 0, 0) a) If size is set before the array is running, do_md_run will fail if size is greater than the default size b) A reshape attempt that reduces the default size to less than the set array size should be blocked 2/ once userspace sets the size the kernel will not change it 3/ writing 'default' to this attribute returns control of the size to the kernel and reverts to the size reported by the personality Also, convert locations that need to know the default size from directly reading ->array_sectors to _size. Resync/reshape operations always follow the default size. Finally, fixup other locations that read a number of 1k-blocks from userspace to use strict_blocks_to_sectors() which checks for unsigned long long to sector_t overflow and blocks to sectors overflow. Reviewed-by: Andre Noll Signed-off-by: Dan Williams --- drivers/md/md.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/md/md.h') diff --git a/drivers/md/md.h b/drivers/md/md.h index ce89dda2407..d13e34f842e 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -147,6 +147,8 @@ struct mddev_s sector_t dev_sectors; /* used size of * component devices */ sector_t array_sectors; /* exported array size */ + int external_size; /* size managed + * externally */ __u64 events; char uuid[16]; @@ -431,3 +433,4 @@ extern void md_new_event(mddev_t *mddev); extern int md_allow_write(mddev_t *mddev); extern void md_wait_for_blocked_rdev(mdk_rdev_t *rdev, mddev_t *mddev); extern void md_set_array_sectors(mddev_t *mddev, sector_t array_sectors); +extern void md_set_array_sectors_lock(mddev_t *mddev, sector_t array_sectors); -- cgit v1.2.3