| Message ID | 20221115013043.360610-7-david@fromorbit.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | xfs, iomap: fix data corrupton due to stale cached iomaps | expand |
On Tue, Nov 15, 2022 at 12:30:40PM +1100, Dave Chinner wrote: > From: Dave Chinner <dchinner@redhat.com> > > All the callers of xfs_bmap_punch_delalloc_range() jump through > hoops to convert a byte range to filesystem blocks before calling > xfs_bmap_punch_delalloc_range(). Instead, pass the byte range to > xfs_bmap_punch_delalloc_range() and have it do the conversion to > filesystem blocks internally. Ok, so we do this here. Why can't we just do this earlier and avoid the strange inbetween stage with a wrapper?
On Tue, Nov 15, 2022 at 12:44:46AM -0800, Christoph Hellwig wrote: > On Tue, Nov 15, 2022 at 12:30:40PM +1100, Dave Chinner wrote: > > From: Dave Chinner <dchinner@redhat.com> > > > > All the callers of xfs_bmap_punch_delalloc_range() jump through > > hoops to convert a byte range to filesystem blocks before calling > > xfs_bmap_punch_delalloc_range(). Instead, pass the byte range to > > xfs_bmap_punch_delalloc_range() and have it do the conversion to > > filesystem blocks internally. > > Ok, so we do this here. Why can't we just do this earlier and > avoid the strange inbetween stage with a wrapper? Probably to avoid rewriting the previous patch with this units change, is my guess. Dave, do you want to merge with this patch 4? I'm satisfied enough with patches 4 and 6 that I'd rather get this out to for-next for further testing than play more patch golf. Reviewed-by: Darrick J. Wong <djwong@kernel.org> --D
On Tue, Nov 15, 2022 at 03:48:33PM -0800, Darrick J. Wong wrote: > On Tue, Nov 15, 2022 at 12:44:46AM -0800, Christoph Hellwig wrote: > > On Tue, Nov 15, 2022 at 12:30:40PM +1100, Dave Chinner wrote: > > > From: Dave Chinner <dchinner@redhat.com> > > > > > > All the callers of xfs_bmap_punch_delalloc_range() jump through > > > hoops to convert a byte range to filesystem blocks before calling > > > xfs_bmap_punch_delalloc_range(). Instead, pass the byte range to > > > xfs_bmap_punch_delalloc_range() and have it do the conversion to > > > filesystem blocks internally. > > > > Ok, so we do this here. Why can't we just do this earlier and > > avoid the strange inbetween stage with a wrapper? > > Probably to avoid rewriting the previous patch with this units change, > is my guess. Dave, do you want to merge with this patch 4? I'm > satisfied enough with patches 4 and 6 that I'd rather get this out to > for-next for further testing than play more patch golf. The fact that Christoph NAK'd exporting mapping_seek_hole_data() this time around is just Plain Fucking Annoying. He didn't say anything in the last thread about it after I explained why I used it, so I had assumed it was all OK. I've already been playing patch golf all morning now to rearrange all the deck chairs to avoid exporting mapping_seek_hole_data(). Instead we now have an exported iomap function that wraps mapping_seek_hole_data, and the wrapper function I added in patch 4 is now the callback function that is passed 3 layers deep into the iomap code. Hence the xfs_buffered_write_delalloc_punch() function needs to remain - we can't elide it entire like this patch does - because now we need a callback function that we can provide to the iomap code so we avoid coupling internal XFS implementation functions to external VFS APIs. -Dave.
On Wed, Nov 16, 2022 at 11:57:23AM +1100, Dave Chinner wrote: > The fact that Christoph NAK'd exporting mapping_seek_hole_data() > this time around is just Plain Fucking Annoying. Thank you so much, I love you too. > He didn't say > anything in the last thread about it after I explained why I used > it, so I had assumed it was all OK. Quote from the last thread: "So, the whole scan for delalloc logic seems pretty generic, I think it can an should be lifted to iomap, with xfs_buffered_write_delalloc_punch provided as a callback." > I've already been playing patch golf all morning now to rearrange > all the deck chairs to avoid exporting mapping_seek_hole_data(). > Instead we now have an exported iomap function that wraps > mapping_seek_hole_data, and the wrapper function I added in patch 4 > is now the callback function that is passed 3 layers deep into the > iomap code. > > Hence the xfs_buffered_write_delalloc_punch() function needs to > remain - we can't elide it entire like this patch does - because now > we need a callback function that we can provide to the iomap code so > we avoid coupling internal XFS implementation functions to external > VFS APIs. Which was roughly was the intention all along.
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 5d1a995b15f8..6aadc5815068 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -114,9 +114,8 @@ xfs_end_ioend( if (unlikely(error)) { if (ioend->io_flags & IOMAP_F_SHARED) { xfs_reflink_cancel_cow_range(ip, offset, size, true); - xfs_bmap_punch_delalloc_range(ip, - XFS_B_TO_FSBT(mp, offset), - XFS_B_TO_FSB(mp, size)); + xfs_bmap_punch_delalloc_range(ip, offset, + offset + size); } goto done; } @@ -455,12 +454,8 @@ xfs_discard_folio( struct folio *folio, loff_t pos) { - struct inode *inode = folio->mapping->host; - struct xfs_inode *ip = XFS_I(inode); + struct xfs_inode *ip = XFS_I(folio->mapping->host); struct xfs_mount *mp = ip->i_mount; - size_t offset = offset_in_folio(folio, pos); - xfs_fileoff_t start_fsb = XFS_B_TO_FSBT(mp, pos); - xfs_fileoff_t pageoff_fsb = XFS_B_TO_FSBT(mp, offset); int error; if (xfs_is_shutdown(mp)) @@ -470,8 +465,9 @@ xfs_discard_folio( "page discard on page "PTR_FMT", inode 0x%llx, pos %llu.", folio, ip->i_ino, pos); - error = xfs_bmap_punch_delalloc_range(ip, start_fsb, - i_blocks_per_folio(inode, folio) - pageoff_fsb); + error = xfs_bmap_punch_delalloc_range(ip, pos, + round_up(pos, folio_size(folio))); + if (error && !xfs_is_shutdown(mp)) xfs_alert(mp, "page discard unable to remove delalloc mapping."); } diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 04d0c2bff67c..867645b74d88 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -590,11 +590,13 @@ xfs_getbmap( int xfs_bmap_punch_delalloc_range( struct xfs_inode *ip, - xfs_fileoff_t start_fsb, - xfs_fileoff_t length) + xfs_off_t start_byte, + xfs_off_t end_byte) { + struct xfs_mount *mp = ip->i_mount; struct xfs_ifork *ifp = &ip->i_df; - xfs_fileoff_t end_fsb = start_fsb + length; + xfs_fileoff_t start_fsb = XFS_B_TO_FSBT(mp, start_byte); + xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, end_byte); struct xfs_bmbt_irec got, del; struct xfs_iext_cursor icur; int error = 0; @@ -607,7 +609,7 @@ xfs_bmap_punch_delalloc_range( while (got.br_startoff + got.br_blockcount > start_fsb) { del = got; - xfs_trim_extent(&del, start_fsb, length); + xfs_trim_extent(&del, start_fsb, end_fsb - start_fsb); /* * A delete can push the cursor forward. Step back to the diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h index 24b37d211f1d..6888078f5c31 100644 --- a/fs/xfs/xfs_bmap_util.h +++ b/fs/xfs/xfs_bmap_util.h @@ -31,7 +31,7 @@ xfs_bmap_rtalloc(struct xfs_bmalloca *ap) #endif /* CONFIG_XFS_RT */ int xfs_bmap_punch_delalloc_range(struct xfs_inode *ip, - xfs_fileoff_t start_fsb, xfs_fileoff_t length); + xfs_off_t start_byte, xfs_off_t end_byte); struct kgetbmap { __s64 bmv_offset; /* file offset of segment in blocks */ diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 2d48fcc7bd6f..04da22943e7c 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -1120,20 +1120,6 @@ xfs_buffered_write_iomap_begin( return error; } -static int -xfs_buffered_write_delalloc_punch( - struct inode *inode, - loff_t start_byte, - loff_t end_byte) -{ - struct xfs_mount *mp = XFS_M(inode->i_sb); - xfs_fileoff_t start_fsb = XFS_B_TO_FSBT(mp, start_byte); - xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, end_byte); - - return xfs_bmap_punch_delalloc_range(XFS_I(inode), start_fsb, - end_fsb - start_fsb); -} - /* * Scan the data range passed to us for dirty page cache folios. If we find a * dirty folio, punch out the preceeding range and update the offset from which @@ -1172,8 +1158,9 @@ xfs_buffered_write_delalloc_scan( if (offset > *punch_start_byte) { int error; - error = xfs_buffered_write_delalloc_punch(inode, - *punch_start_byte, offset); + error = xfs_bmap_punch_delalloc_range( + XFS_I(inode), *punch_start_byte, + offset); if (error) { folio_unlock(folio); folio_put(folio); @@ -1267,7 +1254,7 @@ xfs_buffered_write_delalloc_release( } if (punch_start_byte < end_byte) - error = xfs_buffered_write_delalloc_punch(inode, + error = xfs_bmap_punch_delalloc_range(XFS_I(inode), punch_start_byte, end_byte); out_unlock: filemap_invalidate_unlock(inode->i_mapping);