Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 54 insertions, 0 deletions

diff --git a/fs/efs/symlink.c b/fs/efs/symlink.c
new file mode 100644
index 0000000000..3b03a573cb
--- /dev/null
+++ b/fs/efs/symlink.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * symlink.c
+ *
+ * Copyright (c) 1999 Al Smith
+ *
+ * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
+ */
+
+#include <linux/string.h>
+#include <linux/pagemap.h>
+#include <linux/buffer_head.h>
+#include "efs.h"
+
+static int efs_symlink_read_folio(struct file *file, struct folio *folio)
+{
+	struct page *page = &folio->page;
+	char *link = page_address(page);
+	struct buffer_head * bh;
+	struct inode * inode = page->mapping->host;
+	efs_block_t size = inode->i_size;
+	int err;
+  
+	err = -ENAMETOOLONG;
+	if (size > 2 * EFS_BLOCKSIZE)
+		goto fail;
+  
+	/* read first 512 bytes of link target */
+	err = -EIO;
+	bh = sb_bread(inode->i_sb, efs_bmap(inode, 0));
+	if (!bh)
+		goto fail;
+	memcpy(link, bh->b_data, (size > EFS_BLOCKSIZE) ? EFS_BLOCKSIZE : size);
+	brelse(bh);
+	if (size > EFS_BLOCKSIZE) {
+		bh = sb_bread(inode->i_sb, efs_bmap(inode, 1));
+		if (!bh)
+			goto fail;
+		memcpy(link + EFS_BLOCKSIZE, bh->b_data, size - EFS_BLOCKSIZE);
+		brelse(bh);
+	}
+	link[size] = '\0';
+	SetPageUptodate(page);
+	unlock_page(page);
+	return 0;
+fail:
+	SetPageError(page);
+	unlock_page(page);
+	return err;
+}
+
+const struct address_space_operations efs_symlink_aops = {
+	.read_folio	= efs_symlink_read_folio
+};