btrfs: Sector Size check during Mount
Gracefully fail when trying to mount a BTRFS file system that has a
sectorsize smaller than PAGE_SIZE.
On PPC it is possible to build a FS while using a 4k PAGE_SIZE kernel
then boot into a 64K PAGE_SIZE kernel. Presently open_ctree fails in an
endless loop and hangs the machine in this situation.
My debugging has show this Sector size < Page size to be a non trivial
situation and a graceful exit from the situation would be nice for the
time being.
Signed-off-by: Keith Mannthey <kmannth@us.ibm.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 4c86711..58d0678 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2258,6 +2258,12 @@
goto fail_sb_buffer;
}
+ if (sectorsize < PAGE_SIZE) {
+ printk(KERN_WARNING "btrfs: Incompatible sector size "
+ "found on %s\n", sb->s_id);
+ goto fail_sb_buffer;
+ }
+
mutex_lock(&fs_info->chunk_mutex);
ret = btrfs_read_sys_array(tree_root);
mutex_unlock(&fs_info->chunk_mutex);