From d9da9de2571cfcb93b9f34cc09106cc13e31d72d Mon Sep 17 00:00:00 2001
From: tegge <tegge@FreeBSD.org>
Date: Wed, 26 Mar 2003 19:21:12 +0000
Subject: [PATCH] fp->f_offset doesn't need any protection when it isn't
 accessed.

---
 sys/kern/vfs_vnops.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
index eba9f5d6d5a4..a01733fe8fcd 100644
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -513,9 +513,11 @@ vn_read(fp, uio, active_cred, flags, td)
 	 * According to McKusick the vn lock is protecting f_offset here.
 	 * Once this field has it's own lock we can acquire this shared.
 	 */
-	vn_lock(vp, LK_EXCLUSIVE | LK_NOPAUSE | LK_RETRY, td);
-	if ((flags & FOF_OFFSET) == 0)
+	if ((flags & FOF_OFFSET) == 0) {
+		vn_lock(vp, LK_EXCLUSIVE | LK_NOPAUSE | LK_RETRY, td);
 		uio->uio_offset = fp->f_offset;
+	} else
+		vn_lock(vp, LK_SHARED | LK_NOPAUSE | LK_RETRY, td);
 
 	ioflag |= sequential_heuristic(uio, fp);