From: "Darrick J. Wong" <djwong@xxxxxxxxxx>
Currently only HW which can write at least 1x block is supported.
For supporting atomic writes > 1x block, a CoW-based method will also be
used and this will not be resticted to using HW which can write >= 1x
block.
However for deciding if HW-based atomic writes can be used, we need to
start adding checks for write length < HW min, which complicates the
code. Indeed, a statx field similar to unit_max_opt should also be
added for this minimum, which is undesirable.
HW which can only write > 1x blocks would be uncommon and quite weird,
so let's just not support it.
Signed-off-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>
Signed-off-by: John Garry <john.g.garry@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
---
fs/xfs/xfs_buf.c | 12 ++++++++++++
fs/xfs/xfs_buf.h | 2 +-
fs/xfs/xfs_inode.h | 10 +---------
3 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index e2374c503e79..d52d9587b42c 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -1722,11 +1722,23 @@ static inline void
xfs_configure_buftarg_atomic_writes(
struct xfs_buftarg *btp)
{
+ struct xfs_mount *mp = btp->bt_mount;
unsigned int min_bytes, max_bytes;
min_bytes = bdev_atomic_write_unit_min_bytes(btp->bt_bdev);
max_bytes = bdev_atomic_write_unit_max_bytes(btp->bt_bdev);
+ /*
+ * Ignore atomic write geometry that is nonsense or doesn't even cover
+ * a single fsblock.
+ */
+ if (min_bytes > max_bytes ||
+ min_bytes > mp->m_sb.sb_blocksize ||
+ max_bytes < mp->m_sb.sb_blocksize) {
+ min_bytes = 0;
+ max_bytes = 0;
+ }
+
btp->bt_bdev_awu_min = min_bytes;
btp->bt_bdev_awu_max = max_bytes;
}
diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
index a7026fb255c4..9d2ab567cf81 100644
--- a/fs/xfs/xfs_buf.h
+++ b/fs/xfs/xfs_buf.h
@@ -112,7 +112,7 @@ struct xfs_buftarg {
struct percpu_counter bt_readahead_count;
struct ratelimit_state bt_ioerror_rl;
- /* Atomic write unit values */
+ /* Atomic write unit values, bytes */
unsigned int bt_bdev_awu_min;
unsigned int bt_bdev_awu_max;
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index d3471a7418b9..d7e2b902ef5c 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -358,15 +358,7 @@ static inline bool xfs_inode_has_bigrtalloc(const struct xfs_inode *ip)
static inline bool xfs_inode_can_hw_atomic_write(const struct xfs_inode *ip)
{
- struct xfs_mount *mp = ip->i_mount;
- struct xfs_buftarg *target = xfs_inode_buftarg(ip);
-
- if (mp->m_sb.sb_blocksize < target->bt_bdev_awu_min)
- return false;
- if (mp->m_sb.sb_blocksize > target->bt_bdev_awu_max)
- return false;
-
- return true;
+ return xfs_inode_buftarg(ip)->bt_bdev_awu_max > 0;
}
/*
--
2.31.1
