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From:   Shida Zhang <starzhangzsd@gmail.com>
To:     djwong@kernel.org, dchinner@redhat.com
Cc:     zhangshida@kylinos.cn, starzhangzsd@gmail.com,
        linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org
Subject: [PATCH v2] xfs: add check before calling xfs_mod_fdblocks
Date:   Tue, 21 Jun 2022 15:02:24 +0800
Message-Id: <20220621070224.1231039-1-zhangshida@kylinos.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Checks are missing when delta equals 0 in __xfs_ag_resv_free() and
__xfs_ag_resv_init().

Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
---
 Changes from v1:
 -Add checks before calling xfs_mod_fdblocks instead.

 fs/xfs/libxfs/xfs_ag_resv.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_ag_resv.c b/fs/xfs/libxfs/xfs_ag_resv.c
index fe94058d4e9e..c8fa032e4b00 100644
--- a/fs/xfs/libxfs/xfs_ag_resv.c
+++ b/fs/xfs/libxfs/xfs_ag_resv.c
@@ -149,7 +149,12 @@ __xfs_ag_resv_free(
 		oldresv = resv->ar_orig_reserved;
 	else
 		oldresv = resv->ar_reserved;
-	error = xfs_mod_fdblocks(pag->pag_mount, oldresv, true);
+
+	if (oldresv)
+		error = xfs_mod_fdblocks(pag->pag_mount, oldresv, true);
+	else
+		error = 0;
+
 	resv->ar_reserved = 0;
 	resv->ar_asked = 0;
 	resv->ar_orig_reserved = 0;
@@ -215,8 +220,13 @@ __xfs_ag_resv_init(
 
 	if (XFS_TEST_ERROR(false, mp, XFS_ERRTAG_AG_RESV_FAIL))
 		error = -ENOSPC;
-	else
-		error = xfs_mod_fdblocks(mp, -(int64_t)hidden_space, true);
+	else {
+		error = 0;
+		if (hidden_space)
+			error = xfs_mod_fdblocks(mp, -(int64_t)hidden_space,
+						true);
+	}
+
 	if (error) {
 		trace_xfs_ag_resv_init_error(pag->pag_mount, pag->pag_agno,
 				error, _RET_IP_);
-- 
2.25.1