Re: [PATCH 0/7] xfs: Extend per-inode extent counters.

Darrick J. Wong
2020-06-08T17:31:14Z

On Sat, Jun 06, 2020 at 01:57:38PM +0530, Chandan Babu R wrote:
> The commit xfs: fix inode fork extent count overflow
> (3f8a4f1d876d3e3e49e50b0396eaffcc4ba71b08) mentions that 10 billion
> per-inode data fork extents should be possible to create. However the
> corresponding on-disk field has an signed 32-bit type. Hence this
> patchset extends the on-disk field to 64-bit length out of which only
> the first 47-bits are valid.
>
> Also, XFS has a per-inode xattr extent counter which is 16 bits
> wide. A workload which
> 1. Creates 1 million 255-byte sized xattrs,
> 2. Deletes 50% of these xattrs in an alternating manner,
> 3. Tries to insert 400,000 new 255-byte sized xattrs
> causes the following message to be printed on the console,
>
> XFS (loop0): xfs_iflush_int: detected corrupt incore inode 131, total extents = -19916, nblocks = 102937, ptr ffff9ce33b098c00
> XFS (loop0): xfs_do_force_shutdown(0x8) called from line 3739 of file fs/xfs/xfs_inode.c. Return address = ffffffffa4a94173
>
> This indicates that we overflowed the 16-bits wide xattr extent
> counter.
>
> I have been informed that there are instances where a single file
> has > 100 million hardlinks. With parent pointers being stored in xattr,
> we will overflow the 16-bits wide xattr extent counter when large
> number of hardlinks are created. Hence this patchset extends the
> on-disk field to 32-bit length.
>
> This patchset also includes the previously posted "Fix log reservation
> calculation for xattr insert operation" patch as a bug fix. It
> replaces the xattr set "mount" and "runtime" reservations with just
> one static reservation. Hence we don't need the functionality to
> calculate maximum sized 'xattr set' reservation separately anymore.
>
> The patches can also be obtained from
> https://github.com/chandanr/linux.git at branch xfs-extend-extent-counters.
>
> Chandan Babu R (7):
> xfs: Fix log reservation calculation for xattr insert operation

What happened to that whole patchset with struct xfs_attr_set_resv
and whatnot? Did all that get condensed down to this single patch?

--D

> xfs: Check for per-inode extent count overflow
> xfs: Compute maximum height of directory BMBT separately
> xfs: Add "Use Dir BMBT height" argument to XFS_BM_MAXLEVELS()
> xfs: Use 2^27 as the maximum number of directory extents
> xfs: Extend data extent counter to 47 bits
> xfs: Extend attr extent counter to 32 bits
>
> fs/xfs/libxfs/xfs_attr.c | 11 +--
> fs/xfs/libxfs/xfs_bmap.c | 118 +++++++++++++++++++++++-------
> fs/xfs/libxfs/xfs_bmap.h | 3 +-
> fs/xfs/libxfs/xfs_bmap_btree.h | 4 +-
> fs/xfs/libxfs/xfs_format.h | 49 ++++++++++---
> fs/xfs/libxfs/xfs_inode_buf.c | 65 ++++++++++++++---
> fs/xfs/libxfs/xfs_inode_buf.h | 2 +
> fs/xfs/libxfs/xfs_inode_fork.c | 125 ++++++++++++++++++++++++++++++--
> fs/xfs/libxfs/xfs_inode_fork.h | 2 +
> fs/xfs/libxfs/xfs_log_format.h | 8 +-
> fs/xfs/libxfs/xfs_log_rlimit.c | 29 --------
> fs/xfs/libxfs/xfs_trans_resv.c | 75 +++++++++----------
> fs/xfs/libxfs/xfs_trans_resv.h | 9 +--
> fs/xfs/libxfs/xfs_trans_space.h | 48 ++++++------
> fs/xfs/libxfs/xfs_types.h | 11 ++-
> fs/xfs/scrub/inode.c | 14 ++--
> fs/xfs/xfs_bmap_item.c | 3 +-
> fs/xfs/xfs_inode.c | 10 ++-
> fs/xfs/xfs_inode_item.c | 10 ++-
> fs/xfs/xfs_inode_item_recover.c | 22 +++++-
> fs/xfs/xfs_mount.c | 5 +-
> fs/xfs/xfs_mount.h | 1 +
> fs/xfs/xfs_reflink.c | 4 +-
> 23 files changed, 451 insertions(+), 177 deletions(-)
>
> --
> 2.20.1
>