On Mon, Feb 08, 2016 at 04:17:25PM +1100, Dave Chinner wrote: > On Sun, Feb 07, 2016 at 06:44:09PM -0700, Ross Zwisler wrote: > > On Mon, Feb 08, 2016 at 09:03:29AM +1100, Dave Chinner wrote: > > > On Sun, Feb 07, 2016 at 12:19:12AM -0700, Ross Zwisler wrote: > > > > dax_clear_blocks() needs a valid struct block_device and previously it > > > > was > > > > using inode->i_sb->s_bdev in all cases. This is correct for normal > > > > inodes > > > > on mounted ext2, ext4 and XFS filesystems, but is incorrect for DAX raw > > > > block devices and for XFS real-time devices. > > > > > > > > Instead, have the caller pass in a struct block_device pointer which it > > > > knows to be correct. > > > .... > > > > diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c > > > > index 07ef29b..f722ba2 100644 > > > > --- a/fs/xfs/xfs_bmap_util.c > > > > +++ b/fs/xfs/xfs_bmap_util.c > > > > @@ -73,9 +73,11 @@ xfs_zero_extent( > > > > xfs_daddr_t sector = xfs_fsb_to_db(ip, start_fsb); > > > > sector_t block = XFS_BB_TO_FSBT(mp, sector); > > > > ssize_t size = XFS_FSB_TO_B(mp, count_fsb); > > > > + struct inode *inode = VFS_I(ip); > > > > > > > > if (IS_DAX(VFS_I(ip))) > > > > - return dax_clear_blocks(VFS_I(ip), block, size); > > > > + return dax_clear_blocks(inode, > > > > xfs_find_bdev_for_inode(inode), > > > > + block, size); > > > > > > Get rid of the local inode variable and use VFS_I(ip) like the code > > > originally did. Do not change code that is unrelated to the > > > modifcation being made, especially when it results in making > > > the code an inconsistent mess of mixed pointer constructs.... > > > > The local 'inode' variable was added to avoid multiple calls for VFS_I() for > > the same 'ip'. > > My point is you didn't achieve that. The end result of your patch > is: > > struct inode *inode = VFS_I(ip); > > if (IS_DAX(VFS_I(ip))) > return dax_clear_blocks(inode, xfs_find_bdev_for_inode(inode), > block, size); > > So now we have a local variable, but we still have 2 calls to > VFS_I(ip). i.e. this makes the code harder to read and understand > than before for no benefit.
*facepalm* Yep, thanks for the correction.
