Fixed mandatory reading for legacy

sources/legacy/cifsfs.c

@@ -594,6 +594,49 @@ cifs_get_sb(struct file_system_type *fs_type,
 #endif
 }
 
+static ssize_t cifs_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
+{
+	int retval, read, posix_locking = 0;
+	struct file_lock pfLock;
+	struct cifsInodeInfo *cifsInode;
+	struct cifs_sb_info *cifs_sb;
+	struct cifsTconInfo *tcon;
+
+	cifs_sb = CIFS_SB(filp->f_path.dentry->d_sb);
+	tcon = cifs_sb->tcon;
+	if ((tcon->ses->capabilities & CAP_UNIX) &&
+	    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
+	    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
+		posix_locking = 1;
+
+	retval = cifs_revalidate(filp->f_path.dentry);
+	if (retval < 0)
+		return (ssize_t)retval;
+
+	memset(&pfLock, 0, sizeof(pfLock));
+	pfLock.fl_type = F_RDLCK;
+	pfLock.fl_start = *ppos;
+	pfLock.fl_end = *ppos+len;
+	cifsInode = CIFS_I(filp->f_path.dentry->d_inode);
+	if (cifsInode == NULL)
+		return -ENOENT;
+
+	if (!CIFS_I(filp->f_path.dentry->d_inode)->clientCanCacheRead && !posix_locking) {
+		retval = cifs_lock(filp, F_GETLK, &pfLock);
+		if (retval < 0)
+			return (ssize_t)retval;
+		if (pfLock.fl_type == F_UNLCK)
+			read = do_sync_read(filp, buf, len, ppos);
+		else
+			return -EACCES;
+	} else
+		read = do_sync_read(filp, buf, len, ppos);
+
+	if (read == -EACCES && !posix_locking)
+		read = cifs_user_read(filp, buf, len, ppos);
+	return read;
+}
+
 #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 18)
 static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 				   unsigned long nr_segs, loff_t pos)
@@ -716,7 +759,7 @@ const struct inode_operations cifs_symlink_inode_ops = {
 };
 
 const struct file_operations cifs_file_ops = {
-	.read = do_sync_read,
+	.read = cifs_sync_read,
 	.write = do_sync_write,
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 19)
 	.readv = generic_file_readv,

sources/legacy/inode.c

@@ -1343,13 +1343,9 @@ int cifs_revalidate(struct dentry *direntry)
 			if (direntry->d_inode->i_mapping)
 				filemap_fdatawait(direntry->d_inode->i_mapping);
 
-			/* may eventually have to do this for open files too */
-			if (list_empty(&(cifsInode->openFileList))) {
-				/* changed on server - flush read ahead pages */
-				cFYI(1, ("Invalidating read ahead data on "
-					 "closed file"));
-				invalidate_remote_inode(direntry->d_inode);
-			}
+			cFYI(1, ("Invalidating read ahead data on "
+				 "closed file"));
+			invalidate_remote_inode(direntry->d_inode);
 		}
 	}
 /*	mutex_unlock(&direntry->d_inode->i_mutex); */