Re: [PATCH v9 0/6] Btrfs: implement swap file support

[Omar Sandoval <osandov@osandov.com>]

On Wed, Nov 07, 2018 at 04:28:10PM +0100, David Sterba wrote:
> On Wed, Nov 07, 2018 at 05:07:00PM +0200, Nikolay Borisov wrote:
> > 
> > 
> > On 7.11.18 г. 16:49 ч., David Sterba wrote:
> > > On Tue, Nov 06, 2018 at 10:54:51AM +0100, David Sterba wrote:
> > >> On Thu, Sep 27, 2018 at 11:17:32AM -0700, Omar Sandoval wrote:
> > >>> From: Omar Sandoval <osandov@fb.com>
> > >>> This series implements swap file support for Btrfs.
> > >>>
> > >>> Changes from v8 [1]:
> > >>>
> > >>> - Fixed a bug in btrfs_swap_activate() which would cause us to miss some
> > >>>   file extents if they were merged into one extent map entry.
> > >>> - Fixed build for !CONFIG_SWAP.
> > >>> - Changed all error messages to KERN_WARN.
> > >>> - Unindented long error messages.
> > >>>
> > >>> I've Cc'd Jon and Al on patch 3 this time, so hopefully we can get an
> > >>> ack for that one, too.
> > >>>
> > >>> Thanks!
> > >>>
> > >>> 1: https://www.spinics.net/lists/linux-btrfs/msg82267.html
> > >>>
> > >>> Omar Sandoval (6):
> > >>>   mm: split SWP_FILE into SWP_ACTIVATED and SWP_FS
> > >>>   mm: export add_swap_extent()
> > >>>   vfs: update swap_{,de}activate documentation
> > >>>   Btrfs: prevent ioctls from interfering with a swap file
> > >>>   Btrfs: rename get_chunk_map() and make it non-static
> > >>>   Btrfs: support swap files
> > >>
> > >> fstest generic/472 reports an assertion failure. This is on the updated fstests
> > >> git (70c4067285b0bc076), though it should not matter:
> > >>
> > >> [16597.002190] assertion failed: IS_ALIGNED(start, fs_info->sectorsize) && IS_ALIGNED(end + 1, fs_info->sectorsize), file: fs/btrfs/file-item.c, line: 319
> > > 
> > > I have to revert the patch for now as it kills the testing machines.
> > 
> > The reason is that the isize is not aligned to a sectorsize. Ie it
> > should be:
> > 
> > +       u64 isize = ALIGN_DOWN(i_size_read(inode), fs_info->sectorsize);
> > 
> > With this fixlet generic/472 succeeds.
> 
> Thanks for the fix, I'll fold it in.

Thanks, Nikolay, I missed that. I don't think i_size_read() is
necessary, though, since the inode is locked.