Btrfs: fix regression in btrfs_page_mkwrite() from vm_fault_t conversion
The vm_fault_t conversion commit introduced a ret2 variable for tracking
the integer return values from internal btrfs functions. It was
sometimes returning VM_FAULT_LOCKED for pages that were actually invalid
and had been removed from the radix. Something like this:
ret2 = btrfs_delalloc_reserve_space() // returns zero on success
lock_page(page)
if (page->mapping != inode->i_mapping)
goto out_unlock;
...
out_unlock:
if (!ret2) {
...
return VM_FAULT_LOCKED;
}
This ends up triggering this WARNING in btrfs_destroy_inode()
WARN_ON(BTRFS_I(inode)->block_rsv.size);
xfstests generic/095 was able to reliably reproduce the errors.
Since out_unlock: is only used for errors, this fix moves it below the
if (!ret2) check we use to return VM_FAULT_LOCKED for success.
Fixes: a528a2415087 (btrfs: change return type of btrfs_page_mkwrite to vm_fault_t)
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
1 file changed