ext2: auto disable dax instead of failing mount

Bring the ext2 filesystem in line with xfs that only warns and continues
when the "-o dax" option is specified to mount and the backing device
does not support dax. This is in preparation for removing dax support
from devices that do not enable get_user_pages() operations on dax
mappings. In other words 'gup' support is required and configurations
that were using so called 'page-less' dax will be converted back to
using the page cache.

Removing the broken 'page-less' dax support is a pre-requisite for
removing the "EXPERIMENTAL" warning when mounting a filesystem in dax
mode.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2017-12-21 18:18:27 -08:00
parent 24f3478d66
commit b4b5798cea

View File

@ -959,8 +959,11 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
err = bdev_dax_supported(sb, blocksize);
if (err)
goto failed_mount;
if (err) {
ext2_msg(sb, KERN_ERR,
"DAX unsupported by block device. Turning off DAX.");
sbi->s_mount_opt &= ~EXT2_MOUNT_DAX;
}
}
/* If the blocksize doesn't match, re-read the thing.. */