linux-kernel - [PATCH] smb: client: Improve unlocking of a mutex in cifs_get_swn

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Message-ID: <acc5a7d5-80a3-4c4d-8a43-c44bd962d008@web.de>
Date: Tue, 7 Oct 2025 17:52:23 +0200
From: Markus Elfring <Markus.Elfring@....de>
To: linux-cifs@...r.kernel.org, samba-technical@...ts.samba.org,
 Bharath SM <bharathsm@...rosoft.com>, Paulo Alcantara <pc@...guebit.org>,
 Ronnie Sahlberg <ronniesahlberg@...il.com>,
 Shyam Prasad N <sprasad@...rosoft.com>, Steve French <sfrench@...ba.org>,
 Tom Talpey <tom@...pey.com>
Cc: LKML <linux-kernel@...r.kernel.org>, kernel-janitors@...r.kernel.org
Subject: [PATCH] smb: client: Improve unlocking of a mutex in
 cifs_get_swn_reg()

From: Markus Elfring <elfring@...rs.sourceforge.net>
Date: Tue, 7 Oct 2025 17:45:28 +0200

Use two additional labels so that another bit of common code can be better
reused at the end of this function implementation.

Signed-off-by: Markus Elfring <elfring@...rs.sourceforge.net>
---
 fs/smb/client/cifs_swn.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/fs/smb/client/cifs_swn.c b/fs/smb/client/cifs_swn.c
index 7233c6a7e6d7..35a3e73c1958 100644
--- a/fs/smb/client/cifs_swn.c
+++ b/fs/smb/client/cifs_swn.c
@@ -313,17 +313,15 @@ static struct cifs_swn_reg *cifs_get_swn_reg(struct cifs_tcon *tcon)
 	reg = cifs_find_swn_reg(tcon);
 	if (!IS_ERR(reg)) {
 		kref_get(&reg->ref_count);
-		mutex_unlock(&cifs_swnreg_idr_mutex);
-		return reg;
+		goto unlock;
 	} else if (PTR_ERR(reg) != -EEXIST) {
-		mutex_unlock(&cifs_swnreg_idr_mutex);
-		return reg;
+		goto unlock;
 	}
 
 	reg = kmalloc(sizeof(struct cifs_swn_reg), GFP_ATOMIC);
 	if (reg == NULL) {
-		mutex_unlock(&cifs_swnreg_idr_mutex);
-		return ERR_PTR(-ENOMEM);
+		ret = -ENOMEM;
+		goto fail_unlock;
 	}
 
 	kref_init(&reg->ref_count);
@@ -354,7 +352,7 @@ static struct cifs_swn_reg *cifs_get_swn_reg(struct cifs_tcon *tcon)
 	reg->ip_notify = (tcon->capabilities & SMB2_SHARE_CAP_SCALEOUT);
 
 	reg->tcon = tcon;
-
+unlock:
 	mutex_unlock(&cifs_swnreg_idr_mutex);
 
 	return reg;
@@ -365,6 +363,7 @@ static struct cifs_swn_reg *cifs_get_swn_reg(struct cifs_tcon *tcon)
 	idr_remove(&cifs_swnreg_idr, reg->id);
 fail:
 	kfree(reg);
+fail_unlock:
 	mutex_unlock(&cifs_swnreg_idr_mutex);
 	return ERR_PTR(ret);
 }
-- 
2.51.0