ocfs2: update file system paths to set atime

Conditionally update atime in ocfs2_file_aio_read(), ocfs2_readdir() and
ocfs2_mmap().
Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

fs/ocfs2/dir.c

@@ -82,6 +82,7 @@ int ocfs2_readdir(struct file * filp, void * dirent, filldir_t filldir)
 	struct inode *inode = filp->f_dentry->d_inode;
 	struct super_block * sb = inode->i_sb;
 	unsigned int ra_sectors = 16;
+	int lock_level = 0;
 
 	mlog_entry("dirino=%llu\n",
 		   (unsigned long long)OCFS2_I(inode)->ip_blkno);
@@ -89,7 +90,15 @@ int ocfs2_readdir(struct file * filp, void * dirent, filldir_t filldir)
 	stored = 0;
 	bh = NULL;
 
-	error = ocfs2_meta_lock(inode, NULL, 0);
+	error = ocfs2_meta_lock_atime(inode, filp->f_vfsmnt, &lock_level);
+	if (lock_level && error >= 0) {
+		/* We release EX lock which used to update atime
+		 * and get PR lock again to reduce contention
+		 * on commonly accessed directories. */
+		ocfs2_meta_unlock(inode, 1);
+		lock_level = 0;
+		error = ocfs2_meta_lock(inode, NULL, 0);
+	}
 	if (error < 0) {
 		if (error != -ENOENT)
 			mlog_errno(error);
@@ -198,7 +207,7 @@ int ocfs2_readdir(struct file * filp, void * dirent, filldir_t filldir)
 
 	stored = 0;
 bail:
-	ocfs2_meta_unlock(inode, 0);
+	ocfs2_meta_unlock(inode, lock_level);
 
 bail_nolock:
 	mlog_exit(stored);

fs/ocfs2/file.c

@@ -1254,7 +1254,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
 				   unsigned long nr_segs,
 				   loff_t pos)
 {
-	int ret = 0, rw_level = -1, have_alloc_sem = 0;
+	int ret = 0, rw_level = -1, have_alloc_sem = 0, lock_level = 0;
 	struct file *filp = iocb->ki_filp;
 	struct inode *inode = filp->f_dentry->d_inode;
 
@@ -1296,12 +1296,12 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
 	 * like i_size. This allows the checks down below
 	 * generic_file_aio_read() a chance of actually working. 
 	 */
-	ret = ocfs2_meta_lock(inode, NULL, 0);
+	ret = ocfs2_meta_lock_atime(inode, filp->f_vfsmnt, &lock_level);
 	if (ret < 0) {
 		mlog_errno(ret);
 		goto bail;
 	}
-	ocfs2_meta_unlock(inode, 0);
+	ocfs2_meta_unlock(inode, lock_level);
 
 	ret = generic_file_aio_read(iocb, iov, nr_segs, iocb->ki_pos);
 	if (ret == -EINVAL)

fs/ocfs2/mmap.c

@@ -82,6 +82,8 @@ static struct vm_operations_struct ocfs2_file_vm_ops = {
 
 int ocfs2_mmap(struct file *file, struct vm_area_struct *vma)
 {
+	int ret = 0, lock_level = 0;
+
 	/* We don't want to support shared writable mappings yet. */
 	if (((vma->vm_flags & VM_SHARED) || (vma->vm_flags & VM_MAYSHARE))
 	    && ((vma->vm_flags & VM_WRITE) || (vma->vm_flags & VM_MAYWRITE))) {
@@ -91,7 +93,14 @@ int ocfs2_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 	}
 
-	file_accessed(file);
+	ret = ocfs2_meta_lock_atime(file->f_dentry->d_inode,
+				    file->f_vfsmnt, &lock_level);
+	if (ret < 0) {
+		mlog_errno(ret);
+		goto out;
+	}
+	ocfs2_meta_unlock(file->f_dentry->d_inode, lock_level);
+out:
 	vma->vm_ops = &ocfs2_file_vm_ops;
 	return 0;
 }

fs/ocfs2/symlink.c

@@ -126,6 +126,10 @@ static int ocfs2_readlink(struct dentry *dentry,
 		goto out;
 	}
 
+	/*
+	 * Without vfsmount we can't update atime now,
+	 * but we will update atime here ultimately.
+	 */
 	ret = vfs_readlink(dentry, buffer, buflen, link);
 
 	brelse(bh);