[PATCH 25/29] xfs: support nowait for xfs_buf_item_init()

Hao Xu
2023-08-25T14:06:43Z

support nowait for xfs_buf_item_init() and error out -EAGAIN to
_xfs_trans_bjoin() when it would block.

Signed-off-by: Hao Xu <howeyxu@tencent.com>
---
fs/xfs/xfs_buf_item.c | 9 +++++++--
fs/xfs/xfs_buf_item.h | 2 +-
fs/xfs/xfs_buf_item_recover.c | 2 +-
fs/xfs/xfs_trans_buf.c | 16 +++++++++++++---
4 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index 023d4e0385dd..b1e63137d65b 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -827,7 +827,8 @@ xfs_buf_item_free_format(
int
xfs_buf_item_init(
struct xfs_buf *bp,
- struct xfs_mount *mp)
+ struct xfs_mount *mp,
+ bool nowait)
{
struct xfs_buf_log_item *bip = bp->b_log_item;
int chunks;
@@ -847,7 +848,11 @@ xfs_buf_item_init(
return 0;
}

- bip = kmem_cache_zalloc(xfs_buf_item_cache, GFP_KERNEL | __GFP_NOFAIL);
+ bip = kmem_cache_zalloc(xfs_buf_item_cache,
+ GFP_KERNEL | (nowait ? 0 : __GFP_NOFAIL));
+ if (!bip)
+ return -EAGAIN;
+
xfs_log_item_init(mp, &bip->bli_item, XFS_LI_BUF, &xfs_buf_item_ops);
bip->bli_buf = bp;

diff --git a/fs/xfs/xfs_buf_item.h b/fs/xfs/xfs_buf_item.h
index 4d8a6aece995..b1daf8988280 100644
--- a/fs/xfs/xfs_buf_item.h
+++ b/fs/xfs/xfs_buf_item.h
@@ -47,7 +47,7 @@ struct xfs_buf_log_item {
struct xfs_buf_log_format __bli_format; /* embedded in-log header */
};

-int xfs_buf_item_init(struct xfs_buf *, struct xfs_mount *);
+int xfs_buf_item_init(struct xfs_buf *bp, struct xfs_mount *mp, bool nowait);
void xfs_buf_item_done(struct xfs_buf *bp);
void xfs_buf_item_relse(struct xfs_buf *);
bool xfs_buf_item_put(struct xfs_buf_log_item *);
diff --git a/fs/xfs/xfs_buf_item_recover.c b/fs/xfs/xfs_buf_item_recover.c
index 43167f543afc..aa64d5a499d6 100644
--- a/fs/xfs/xfs_buf_item_recover.c
+++ b/fs/xfs/xfs_buf_item_recover.c
@@ -429,7 +429,7 @@ xlog_recover_validate_buf_type(
struct xfs_buf_log_item *bip;

bp->b_flags |= _XBF_LOGRECOVERY;
- xfs_buf_item_init(bp, mp);
+ xfs_buf_item_init(bp, mp, false);
bip = bp->b_log_item;
bip->bli_item.li_lsn = current_lsn;
}
diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
index 016371f58f26..a1e4f2e8629a 100644
--- a/fs/xfs/xfs_trans_buf.c
+++ b/fs/xfs/xfs_trans_buf.c
@@ -57,13 +57,14 @@ xfs_trans_buf_item_match(
* If the buffer does not yet have a buf log item associated with it,
* then allocate one for it. Then add the buf item to the transaction.
*/
-STATIC void
+STATIC int
_xfs_trans_bjoin(
struct xfs_trans *tp,
struct xfs_buf *bp,
int reset_recur)
{
struct xfs_buf_log_item *bip;
+ int ret;

ASSERT(bp->b_transp == NULL);

@@ -72,7 +73,11 @@ _xfs_trans_bjoin(
* it doesn't have one yet, then allocate one and initialize it.
* The checks to see if one is there are in xfs_buf_item_init().
*/
- xfs_buf_item_init(bp, tp->t_mountp);
+ ret = xfs_buf_item_init(bp, tp->t_mountp,
+ tp->t_flags & XFS_TRANS_NOWAIT);
+ if (ret < 0)
+ return ret;
+
bip = bp->b_log_item;
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
@@ -92,6 +97,7 @@ _xfs_trans_bjoin(
xfs_trans_add_item(tp, &bip->bli_item);
bp->b_transp = tp;

+ return 0;
}

void
@@ -309,7 +315,11 @@ xfs_trans_read_buf_map(
}

if (tp) {
- _xfs_trans_bjoin(tp, bp, 1);
+ error = _xfs_trans_bjoin(tp, bp, 1);
+ if (error) {
+ xfs_buf_relse(bp);
+ return error;
+ }
trace_xfs_trans_read_buf(bp->b_log_item);
}
ASSERT(bp->b_ops != NULL || ops == NULL);
--
2.25.1