Move execve's access time update functionality into a new

vfs_mark_atime() function, and use the new function for
performing efficient atime updates in mmap().

Reviewed by:	bde
MFC after:	2 weeks

5 files changed, 25 insertions, 27 deletions

diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 2b7dd32..d235b31 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -292,7 +292,7 @@ do_execve(td, args, mac_p)
 	register_t *stack_base;
 	int error, len, i;
 	struct image_params image_params, *imgp;
-	struct vattr atimeattr, attr;
+	struct vattr attr;
 	int (*img_first)(struct image_params *);
 	struct pargs *oldargs = NULL, *newargs = NULL;
 	struct sigacts *oldsigacts, *newsigacts;
@@ -709,17 +709,7 @@ interpret:
 		exec_setregs(td, imgp->entry_addr,
 		    (u_long)(uintptr_t)stack_base, imgp->ps_strings);
 
-	/*
-	 * Here we should update the access time of the file.  This must
-	 * be implemented by the underlying filesystem in the same way as
-	 * access timestamps for a VOP_READ() because we want to avoid
-	 * blocking and/or I/O, and have not called vn_start_write().
-	 */
-	if ((imgp->vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) {
-		VATTR_NULL(&atimeattr);
-		atimeattr.va_vaflags |= VA_EXECVE_ATIME;
-		(void)VOP_SETATTR(imgp->vp, &atimeattr, td->td_ucred, td);
-	}
+	vfs_mark_atime(imgp->vp, td);
 
 done1:
 	/*
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 26d5b9f..4e3d771 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -3881,3 +3881,20 @@ vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off)
 	return (0);
 }
 
+/*
+ * Mark for update the access time of the file if the filesystem
+ * supports VA_MARK_ATIME.  This functionality is used by execve
+ * and mmap, so we want to avoid the synchronous I/O implied by
+ * directly setting va_atime for the sake of efficiency.
+ */
+void
+vfs_mark_atime(struct vnode *vp, struct thread *td)
+{
+	struct vattr atimeattr;
+
+	if ((vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) {
+		VATTR_NULL(&atimeattr);
+		atimeattr.va_vaflags |= VA_MARK_ATIME;
+		(void)VOP_SETATTR(vp, &atimeattr, td->td_ucred, td);
+	}
+}
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
index 52a1d2f..4073e41 100644
--- a/sys/sys/vnode.h
+++ b/sys/sys/vnode.h
@@ -285,7 +285,7 @@ struct vattr {
  */
 #define	VA_UTIMES_NULL	0x01		/* utimes argument was NULL */
 #define	VA_EXCLUSIVE	0x02		/* exclusive create request */
-#define	VA_EXECVE_ATIME	0x04		/* setting atime for execve */
+#define	VA_MARK_ATIME	0x04		/* setting atime for execve/mmap */
 
 /*
  * Flags for ioflag. (high 16 bits used to ask for read-ahead and
@@ -727,6 +727,7 @@ void vfs_hash_rehash(struct vnode *vp, u_int hash);
 void vfs_hash_remove(struct vnode *vp);
 
 int vfs_kqfilter(struct vop_kqfilter_args *);
+void vfs_mark_atime(struct vnode *vp, struct thread *td);
 struct dirent;
 int vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off);
 
diff --git a/sys/ufs/ufs/ufs_vnops.c b/sys/ufs/ufs/ufs_vnops.c
index 9a04787..b26756c 100644
--- a/sys/ufs/ufs/ufs_vnops.c
+++ b/sys/ufs/ufs/ufs_vnops.c
@@ -437,13 +437,13 @@ ufs_setattr(ap)
 		return (EINVAL);
 	}
 	/*
-	 * Update the file's access time when it has been executed.  We are
-	 * doing this here to specifically avoid some of the checks done
+	 * Mark for update the file's access time for vfs_mark_atime().
+	 * We are doing this here to avoid some of the checks done
 	 * below -- this operation is done by request of the kernel and
 	 * should bypass some security checks.  Things like read-only
 	 * checks get handled by other levels (e.g., ffs_update()).
 	 */
-	if (vap->va_vaflags & VA_EXECVE_ATIME) {
+	if (vap->va_vaflags & VA_MARK_ATIME) {
 		ip->i_flag |= IN_ACCESS;
 		return (0);
 	}
diff --git a/sys/vm/vm_mmap.c b/sys/vm/vm_mmap.c
index ab3349e..9379c3b 100644
--- a/sys/vm/vm_mmap.c
+++ b/sys/vm/vm_mmap.c
@@ -1164,18 +1164,8 @@ vm_mmap_vnode(struct thread *td, vm_size_t objsize,
 	}
 	*objp = obj;
 	*flagsp = flags;
+	vfs_mark_atime(vp, td);
 
-	/* Update access time. */
-	if ((vp->v_mount->mnt_flag & MNT_NOATIME) == 0) {
-		struct vattr vattr;
-		struct timespec ts;
-
-		VATTR_NULL(&vattr);
-		vfs_timestamp(&ts);
-		vattr.va_atime = ts;
-		(void)VOP_SETATTR(vp, &vattr, td->td_ucred, td);
-
-	}
 done:
 	vput(vp);
 	VFS_UNLOCK_GIANT(vfslocked);