[src/trunk]: src/sys/kern It is impossible for VOP_LOCK() to return ENOENT wi...

[hannken <hannken%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c26689b257ce
branches:  trunk
changeset: 364441:c26689b257ce
user:      hannken <hannken%NetBSD.org@localhost>
date:      Fri Mar 25 08:57:15 2022 +0000

description:
It is impossible for VOP_LOCK() to return ENOENT with LK_RETRY flag.
Remove the second call to VOP_LOCK().

Enable assertion "vrefcnt(vp) > 0" and assert all possible errors
for all LK_RETRY/LK_NOWAIT combinations.

diffstat:

 sys/kern/vfs_vnops.c |  26 +++++++++++++++++---------
 1 files changed, 17 insertions(+), 9 deletions(-)

diffs (57 lines):

diff -r 42e8b054a849 -r c26689b257ce sys/kern/vfs_vnops.c
--- a/sys/kern/vfs_vnops.c      Fri Mar 25 08:56:36 2022 +0000
+++ b/sys/kern/vfs_vnops.c      Fri Mar 25 08:57:15 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_vnops.c,v 1.226 2022/03/19 13:50:02 hannken Exp $  */
+/*     $NetBSD: vfs_vnops.c,v 1.227 2022/03/25 08:57:15 hannken Exp $  */
 
 /*-
  * Copyright (c) 2009 The NetBSD Foundation, Inc.
@@ -66,7 +66,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_vnops.c,v 1.226 2022/03/19 13:50:02 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_vnops.c,v 1.227 2022/03/25 08:57:15 hannken Exp $");
 
 #include "veriexec.h"
 
@@ -1192,9 +1192,7 @@
        struct lwp *l;
        int error;
 
-#if 0
-       KASSERT(vrefcnt(vp) > 0 || (vp->v_iflag & VI_ONWORKLST) != 0);
-#endif
+       KASSERT(vrefcnt(vp) > 0);
        KASSERT((flags & ~(LK_SHARED|LK_EXCLUSIVE|LK_NOWAIT|LK_RETRY|
            LK_UPGRADE|LK_DOWNGRADE)) == 0);
        KASSERT((flags & LK_NOWAIT) != 0 || !mutex_owned(vp->v_interlock));
@@ -1210,13 +1208,23 @@
        l->l_rwcallsite = (uintptr_t)__builtin_return_address(0);       
 
        error = VOP_LOCK(vp, flags);
-       if ((flags & LK_RETRY) != 0 && error == ENOENT)
-               error = VOP_LOCK(vp, flags);
 
        l->l_rwcallsite = 0;
 
-       KASSERT((flags & LK_RETRY) == 0 || (flags & LK_NOWAIT) != 0 ||
-           error == 0);
+       switch (flags & (LK_RETRY | LK_NOWAIT)) {
+       case 0:
+               KASSERT(error == 0 || error == ENOENT);
+               break;
+       case LK_RETRY:
+               KASSERT(error == 0);
+               break;
+       case LK_NOWAIT:
+               KASSERT(error == 0 || error == EBUSY || error == ENOENT);
+               break;
+       case LK_RETRY | LK_NOWAIT:
+               KASSERT(error == 0 || error == EBUSY);
+               break;
+       }
 
        return error;
 }