xfs: refactor xfs_icache_free_{eof,cow}blocks call sites

In anticipation of more restructuring of the eof/cowblocks gc code,
refactor calling of those two functions into a single internal helper
function, then present a new standard interface to purge speculative
block preallocations and start shifting higher level code to use that.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>

Author: Darrick J. Wong

fs/xfs/xfs_file.c

@@ -718,8 +718,7 @@ xfs_file_buffered_aio_write(
 
 		xfs_iunlock(ip, iolock);
 		eofb.eof_flags = XFS_EOF_FLAGS_SYNC;
-		xfs_icache_free_eofblocks(ip->i_mount, &eofb);
-		xfs_icache_free_cowblocks(ip->i_mount, &eofb);
+		xfs_blockgc_free_space(ip->i_mount, &eofb);
 		goto write_retry;
 	}
 

fs/xfs/xfs_icache.c

@@ -1645,6 +1645,38 @@ xfs_start_block_reaping(
 	xfs_queue_cowblocks(mp);
 }
 
+/* Scan all incore inodes for block preallocations that we can remove. */
+static inline int
+xfs_blockgc_scan(
+	struct xfs_mount	*mp,
+	struct xfs_eofblocks	*eofb)
+{
+	int			error;
+
+	error = xfs_icache_free_eofblocks(mp, eofb);
+	if (error)
+		return error;
+
+	error = xfs_icache_free_cowblocks(mp, eofb);
+	if (error)
+		return error;
+
+	return 0;
+}
+
+/*
+ * Try to free space in the filesystem by purging eofblocks and cowblocks.
+ */
+int
+xfs_blockgc_free_space(
+	struct xfs_mount	*mp,
+	struct xfs_eofblocks	*eofb)
+{
+	trace_xfs_blockgc_free_space(mp, eofb, _RET_IP_);
+
+	return xfs_blockgc_scan(mp, eofb);
+}
+
 /*
  * Run cow/eofblocks scans on the supplied dquots.  We don't know exactly which
  * quota caused an allocation failure, so we make a best effort by including
@@ -1665,7 +1697,6 @@ xfs_blockgc_free_dquots(
 {
 	struct xfs_eofblocks	eofb = {0};
 	bool			do_work = false;
-	int			error;
 
 	if (!udqp && !gdqp && !pdqp)
 		return 0;
@@ -1697,11 +1728,7 @@ xfs_blockgc_free_dquots(
 	if (!do_work)
 		return 0;
 
-	error = xfs_icache_free_eofblocks(mp, &eofb);
-	if (error)
-		return error;
-
-	return xfs_icache_free_cowblocks(mp, &eofb);
+	return xfs_blockgc_free_space(mp, &eofb);
 }
 
 /* Run cow/eofblocks scans on the quotas attached to the inode. */

fs/xfs/xfs_icache.h

@@ -58,6 +58,7 @@ int xfs_blockgc_free_dquots(struct xfs_mount *mp, struct xfs_dquot *udqp,
 		struct xfs_dquot *gdqp, struct xfs_dquot *pdqp,
 		unsigned int eof_flags);
 int xfs_blockgc_free_quota(struct xfs_inode *ip, unsigned int eof_flags);
+int xfs_blockgc_free_space(struct xfs_mount *mp, struct xfs_eofblocks *eofb);
 
 void xfs_inode_set_eofblocks_tag(struct xfs_inode *ip);
 void xfs_inode_clear_eofblocks_tag(struct xfs_inode *ip);

fs/xfs/xfs_trace.h

@@ -3928,6 +3928,7 @@ DEFINE_EVENT(xfs_eofblocks_class, name,	\
 		 unsigned long caller_ip), \
 	TP_ARGS(mp, eofb, caller_ip))
 DEFINE_EOFBLOCKS_EVENT(xfs_ioc_free_eofblocks);
+DEFINE_EOFBLOCKS_EVENT(xfs_blockgc_free_space);
 
 #endif /* _TRACE_XFS_H */