Hi all, Here's v3 of the imap cache invalidation series. To recap from v2, patch 5 of that series added a lookup and extent trim to xfs_iomap_write_allocate() to ensure delalloc conversion always had a correct range. Christoph didn't like this approach and has an alternate proposal to modify XFS_BMAPI_DELALLOC behavior to always skip holes. That approach is problematic because it can potentially convert blocks that have nothing to do with the current extent (i.e., still racy with hole punch). As a compromise, this version implements an xfs_bmapi_delalloc() wrapper with an interface that allocates the underlying extent of a particular block. This ensures that writeback always uses the correct range without adding an extra extent lookup. There is still a bit of hackiness and probably opportunity for broader refactoring, but that can be done once we've established correctness. Patches 1-4 are mostly unchanged from v2. Patch 5 introduces the xfs_bmapi_delalloc() helper. Patch 6 modifies xfs_iomap_write_allocate() to use xfs_bmapi_delalloc() instead of xfs_bmapi_write(). This series survives fstests (including repeated cycles of generic/524 and xfs/442) on 4k and 1k block sizes with reflink enabled without any regressions. It also survives several million fsx operations. Thoughts, reviews, flames appreciated. Brian v3: - Move comment in xfs_imap_valid(). - Replace lookup+trim in xfs_iomap_write_allocate() with xfs_bmapi_delalloc() wrapper mechanism. v2: https://marc.info/?l=linux-xfs&m=154775280823464&w=2 - Refactor validation logic into xfs_imap_valid() helper. - Revalidate seqno after the lock cycle in xfs_map_blocks(). - Update *seq in xfs_iomap_write_allocate() regardless of fork type. - Add patch 5 for seqno revalidation on xfs_iomap_write_allocate() lock cycles. v1: https://marc.info/?l=linux-xfs&m=154721212321112&w=2 Brian Foster (6): xfs: eof trim writeback mapping as soon as it is cached xfs: update fork seq counter on data fork changes xfs: validate writeback mapping using data fork seq counter xfs: remove superfluous writeback mapping eof trimming xfs: create delalloc bmapi wrapper for full extent allocation xfs: use the latest extent at writeback delalloc conversion time fs/xfs/libxfs/xfs_bmap.c | 58 ++++++++--- fs/xfs/libxfs/xfs_bmap.h | 3 +- fs/xfs/libxfs/xfs_iext_tree.c | 13 ++- fs/xfs/libxfs/xfs_inode_fork.h | 2 +- fs/xfs/xfs_aops.c | 71 ++++++++----- fs/xfs/xfs_iomap.c | 175 ++++++++++++--------------------- 6 files changed, 162 insertions(+), 160 deletions(-) -- 2.17.2
