fs: add support for SquashFS 4.0

The driver was imported from Linux 4.4.

Current implementation supports only XZ decompressor.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Tested-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 35 insertions, 0 deletions

diff --git a/fs/squashfs/file_cache.c b/fs/squashfs/file_cache.c
new file mode 100644
index 0000000000..9443e4558d
--- /dev/null
+++ b/fs/squashfs/file_cache.c
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2013
+ * Phillip Lougher <phillip@squashfs.org.uk>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/pagemap.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+/* Read separately compressed datablock and memcopy into page cache */
+int squashfs_readpage_block(struct page *page, u64 block, int bsize)
+{
+	struct inode *i = page->inode;
+	struct squashfs_cache_entry *buffer = squashfs_get_datablock(i->i_sb,
+		block, bsize);
+	int res = buffer->error;
+
+	if (res)
+		ERROR("Unable to read page, block %llx, size %x\n", block,
+			bsize);
+	else
+		squashfs_copy_cache(page, buffer, buffer->length, 0);
+
+	squashfs_cache_put(buffer);
+	return res;
+}