diff options
Diffstat (limited to 'sys/kern/vfs_default.c')
| -rw-r--r-- | sys/kern/vfs_default.c | 37 |
1 files changed, 23 insertions, 14 deletions
diff --git a/sys/kern/vfs_default.c b/sys/kern/vfs_default.c index 2c01117..94b8149 100644 --- a/sys/kern/vfs_default.c +++ b/sys/kern/vfs_default.c @@ -399,17 +399,24 @@ int vop_stdadvlock(struct vop_advlock_args *ap) { struct vnode *vp; - struct ucred *cred; struct vattr vattr; int error; vp = ap->a_vp; - cred = curthread->td_ucred; - vn_lock(vp, LK_SHARED | LK_RETRY); - error = VOP_GETATTR(vp, &vattr, cred); - VOP_UNLOCK(vp, 0); - if (error) - return (error); + if (ap->a_fl->l_whence == SEEK_END) { + /* + * The NFSv4 server must avoid doing a vn_lock() here, since it + * can deadlock the nfsd threads, due to a LOR. Fortunately + * the NFSv4 server always uses SEEK_SET and this code is + * only required for the SEEK_END case. + */ + vn_lock(vp, LK_SHARED | LK_RETRY); + error = VOP_GETATTR(vp, &vattr, curthread->td_ucred); + VOP_UNLOCK(vp, 0); + if (error) + return (error); + } else + vattr.va_size = 0; return (lf_advlock(ap, &(vp->v_lockf), vattr.va_size)); } @@ -418,17 +425,19 @@ int vop_stdadvlockasync(struct vop_advlockasync_args *ap) { struct vnode *vp; - struct ucred *cred; struct vattr vattr; int error; vp = ap->a_vp; - cred = curthread->td_ucred; - vn_lock(vp, LK_SHARED | LK_RETRY); - error = VOP_GETATTR(vp, &vattr, cred); - VOP_UNLOCK(vp, 0); - if (error) - return (error); + if (ap->a_fl->l_whence == SEEK_END) { + /* The size argument is only needed for SEEK_END. */ + vn_lock(vp, LK_SHARED | LK_RETRY); + error = VOP_GETATTR(vp, &vattr, curthread->td_ucred); + VOP_UNLOCK(vp, 0); + if (error) + return (error); + } else + vattr.va_size = 0; return (lf_advlockasync(ap, &(vp->v_lockf), vattr.va_size)); } |
