lustre/clio: honor O_NOATIME

Add a ci_noatime bit to struct cl_io. In ll_io_init() set this bit if
O_NOATIME is set in f_flags. Ensure that this bit is propagated down
to lower layers. In osc_io_read_start() don't update atime if this bit
is set. Add sanity test 39n to check that passing O_NOATIME to open()
is honored.
Signed-off-by: John L. Hammond <john.hammond@intel.com>
Reviewed-on: http://review.whamcloud.com/7442
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3832Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/include/cl_object.h

@@ -2392,7 +2392,11 @@ struct cl_io {
 	/**
 	 * file is released, restore has to to be triggered by vvp layer
 	 */
-			     ci_restore_needed:1;
+			     ci_restore_needed:1,
+	/**
+	 * O_NOATIME
+	 */
+			     ci_noatime:1;
 	/**
 	 * Number of pages owned by this IO. For invariant checking.
 	 */

drivers/staging/lustre/lustre/llite/file.c

@@ -1035,6 +1035,33 @@ int ll_glimpse_ioctl(struct ll_sb_info *sbi, struct lov_stripe_md *lsm,
 	return rc;
 }
 
+static bool file_is_noatime(const struct file *file)
+{
+	const struct vfsmount *mnt = file->f_path.mnt;
+	const struct inode *inode = file->f_path.dentry->d_inode;
+
+	/* Adapted from file_accessed() and touch_atime().*/
+	if (file->f_flags & O_NOATIME)
+		return true;
+
+	if (inode->i_flags & S_NOATIME)
+		return true;
+
+	if (IS_NOATIME(inode))
+		return true;
+
+	if (mnt->mnt_flags & (MNT_NOATIME | MNT_READONLY))
+		return true;
+
+	if ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode))
+		return true;
+
+	if ((inode->i_sb->s_flags & MS_NODIRATIME) && S_ISDIR(inode->i_mode))
+		return true;
+
+	return false;
+}
+
 void ll_io_init(struct cl_io *io, const struct file *file, int write)
 {
 	struct inode *inode = file->f_dentry->d_inode;
@@ -1054,6 +1081,8 @@ void ll_io_init(struct cl_io *io, const struct file *file, int write)
 	} else if (file->f_flags & O_APPEND) {
 		io->ci_lockreq = CILR_MANDATORY;
 	}
+
+	io->ci_noatime = file_is_noatime(file);
 }
 
 static ssize_t

drivers/staging/lustre/lustre/lov/lov_io.c

@@ -194,6 +194,7 @@ static int lov_io_sub_init(const struct lu_env *env, struct lov_io *lio,
 		sub_io->ci_lockreq = io->ci_lockreq;
 		sub_io->ci_type    = io->ci_type;
 		sub_io->ci_no_srvlock = io->ci_no_srvlock;
+		sub_io->ci_noatime = io->ci_noatime;
 
 		lov_sub_enter(sub);
 		result = cl_io_sub_init(sub->sub_env, sub_io,

drivers/staging/lustre/lustre/osc/osc_io.c

@@ -512,19 +512,15 @@ static int osc_io_read_start(const struct lu_env *env,
 	struct osc_io    *oio   = cl2osc_io(env, slice);
 	struct cl_object *obj   = slice->cis_obj;
 	struct cl_attr   *attr  = &osc_env_info(env)->oti_attr;
-	int	      result = 0;
+	int rc = 0;
 
-	if (oio->oi_lockless == 0) {
+	if (oio->oi_lockless == 0 && !slice->cis_io->ci_noatime) {
 		cl_object_attr_lock(obj);
-		result = cl_object_attr_get(env, obj, attr);
-		if (result == 0) {
-			attr->cat_atime = LTIME_S(CURRENT_TIME);
-			result = cl_object_attr_set(env, obj, attr,
-						    CAT_ATIME);
-		}
+		attr->cat_atime = LTIME_S(CURRENT_TIME);
+		rc = cl_object_attr_set(env, obj, attr, CAT_ATIME);
 		cl_object_attr_unlock(obj);
 	}
-	return result;
+	return rc;
 }
 
 static int osc_io_write_start(const struct lu_env *env,