git: 318c56714aa8 - main - fuse_vnop_copy_file_range(): use vn_lock_pair()

[Konstantin Belousov]

The branch main has been updated by kib:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=318c56714aa8c170132ebe008f52904e0f119b5f

commit 318c56714aa8c170132ebe008f52904e0f119b5f
Author:     Konstantin Belousov <k...@freebsd.org>
AuthorDate: 2023-11-14 22:48:47 +0000
Commit:     Konstantin Belousov <k...@freebsd.org>
CommitDate: 2023-11-16 20:10:30 +0000

    fuse_vnop_copy_file_range(): use vn_lock_pair()
    
    Reviewed by:    asomers, jah
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Differential revision:  https://reviews.freebsd.org/D42625
---
 sys/fs/fuse/fuse_vnops.c | 22 +++++-----------------
 1 file changed, 5 insertions(+), 17 deletions(-)

diff --git a/sys/fs/fuse/fuse_vnops.c b/sys/fs/fuse/fuse_vnops.c
index 3249e5988801..aead188276ec 100644
--- a/sys/fs/fuse/fuse_vnops.c
+++ b/sys/fs/fuse/fuse_vnops.c
@@ -879,23 +879,11 @@ fuse_vnop_copy_file_range(struct vop_copy_file_range_args 
*ap)
                td = ap->a_fsizetd;
        pid = td->td_proc->p_pid;
 
-       /* Lock both vnodes, avoiding risk of deadlock. */
-       do {
-               err = vn_lock(outvp, LK_EXCLUSIVE);
-               if (invp == outvp)
-                       break;
-               if (err == 0) {
-                       err = vn_lock(invp, LK_SHARED | LK_NOWAIT);
-                       if (err == 0)
-                               break;
-                       VOP_UNLOCK(outvp);
-                       err = vn_lock(invp, LK_SHARED);
-                       if (err == 0)
-                               VOP_UNLOCK(invp);
-               }
-       } while (err == 0);
-       if (err != 0)
-               return (err);
+       vn_lock_pair(invp, false, LK_SHARED, outvp, false, LK_EXCLUSIVE);
+       if (invp->v_data == NULL || outvp->v_data == NULL) {
+               err = EBADF;
+               goto unlock;
+       }
 
        err = fuse_filehandle_getrw(invp, FREAD, &infufh, incred, pid);
        if (err)