xfs: add a b_iodone callback to struct xfs_buf

Stop open coding the log item completions and instead add a callback
into back into the submitter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Acked-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>

Author: Christoph Hellwig

fs/xfs/xfs_buf.c

@@ -1392,11 +1392,8 @@ xfs_buf_ioend(
 		if (bp->b_log_item)
 			xfs_buf_item_done(bp);
 
-		if (bp->b_flags & _XBF_INODES)
-			xfs_buf_inode_iodone(bp);
-		else if (bp->b_flags & _XBF_DQUOTS)
-			xfs_buf_dquot_iodone(bp);
-
+		if (bp->b_iodone)
+			bp->b_iodone(bp);
 	}
 
 	bp->b_flags &= ~(XBF_READ | XBF_WRITE | XBF_READ_AHEAD |

fs/xfs/xfs_buf.h

@@ -34,8 +34,6 @@ struct xfs_buf;
 #define XBF_WRITE_FAIL	 (1u << 7) /* async writes have failed on this buffer */
 
 /* buffer type flags for write callbacks */
-#define _XBF_INODES	 (1u << 16)/* inode buffer */
-#define _XBF_DQUOTS	 (1u << 17)/* dquot buffer */
 #define _XBF_LOGRECOVERY (1u << 18)/* log recovery buffer */
 
 /* flags used only internally */
@@ -65,8 +63,6 @@ typedef unsigned int xfs_buf_flags_t;
 	{ XBF_DONE,		"DONE" }, \
 	{ XBF_STALE,		"STALE" }, \
 	{ XBF_WRITE_FAIL,	"WRITE_FAIL" }, \
-	{ _XBF_INODES,		"INODES" }, \
-	{ _XBF_DQUOTS,		"DQUOTS" }, \
 	{ _XBF_LOGRECOVERY,	"LOG_RECOVERY" }, \
 	{ _XBF_PAGES,		"PAGES" }, \
 	{ _XBF_KMEM,		"KMEM" }, \
@@ -205,6 +201,7 @@ struct xfs_buf {
 	unsigned int		b_offset;	/* page offset of b_addr,
 						   only for _XBF_KMEM buffers */
 	int			b_error;	/* error code on I/O */
+	void			(*b_iodone)(struct xfs_buf *bp);
 
 	/*
 	 * async write failure retry count. Initialised to zero on the first

fs/xfs/xfs_dquot.c

@@ -1451,7 +1451,7 @@ xfs_qm_dqflush(
 	 * Attach the dquot to the buffer so that we can remove this dquot from
 	 * the AIL and release the flush lock once the dquot is synced to disk.
 	 */
-	bp->b_flags |= _XBF_DQUOTS;
+	bp->b_iodone = xfs_buf_dquot_iodone;
 	list_add_tail(&lip->li_bio_list, &bp->b_li_list);
 
 	/*

fs/xfs/xfs_inode_item.c

@@ -199,7 +199,7 @@ xfs_inode_item_precommit(
 		xfs_buf_hold(bp);
 		spin_lock(&iip->ili_lock);
 		iip->ili_item.li_buf = bp;
-		bp->b_flags |= _XBF_INODES;
+		bp->b_iodone = xfs_buf_inode_iodone;
 		list_add_tail(&iip->ili_item.li_bio_list, &bp->b_li_list);
 		xfs_trans_brelse(tp, bp);
 	}

fs/xfs/xfs_trans_buf.c

@@ -659,7 +659,7 @@ xfs_trans_inode_buf(
 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
 
 	bip->bli_flags |= XFS_BLI_INODE_BUF;
-	bp->b_flags |= _XBF_INODES;
+	bp->b_iodone = xfs_buf_inode_iodone;
 	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
 }
 
@@ -684,7 +684,7 @@ xfs_trans_stale_inode_buf(
 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
 
 	bip->bli_flags |= XFS_BLI_STALE_INODE;
-	bp->b_flags |= _XBF_INODES;
+	bp->b_iodone = xfs_buf_inode_iodone;
 	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
 }
 
@@ -709,7 +709,7 @@ xfs_trans_inode_alloc_buf(
 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
 
 	bip->bli_flags |= XFS_BLI_INODE_ALLOC_BUF;
-	bp->b_flags |= _XBF_INODES;
+	bp->b_iodone = xfs_buf_inode_iodone;
 	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
 }
 
@@ -820,6 +820,6 @@ xfs_trans_dquot_buf(
 		break;
 	}
 
-	bp->b_flags |= _XBF_DQUOTS;
+	bp->b_iodone = xfs_buf_dquot_iodone;
 	xfs_trans_buf_set_type(tp, bp, type);
 }