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-rw-r--r--kernel/fs/nfs/symlink.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/kernel/fs/nfs/symlink.c b/kernel/fs/nfs/symlink.c
new file mode 100644
index 000000000..2d5620065
--- /dev/null
+++ b/kernel/fs/nfs/symlink.c
@@ -0,0 +1,78 @@
+/*
+ * linux/fs/nfs/symlink.c
+ *
+ * Copyright (C) 1992 Rick Sladkey
+ *
+ * Optimization changes Copyright (C) 1994 Florian La Roche
+ *
+ * Jun 7 1999, cache symlink lookups in the page cache. -DaveM
+ *
+ * nfs symlink handling code
+ */
+
+#include <linux/time.h>
+#include <linux/errno.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/nfs.h>
+#include <linux/nfs2.h>
+#include <linux/nfs_fs.h>
+#include <linux/pagemap.h>
+#include <linux/stat.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/namei.h>
+
+/* Symlink caching in the page cache is even more simplistic
+ * and straight-forward than readdir caching.
+ */
+
+static int nfs_symlink_filler(struct inode *inode, struct page *page)
+{
+ int error;
+
+ error = NFS_PROTO(inode)->readlink(inode, page, 0, PAGE_SIZE);
+ if (error < 0)
+ goto error;
+ SetPageUptodate(page);
+ unlock_page(page);
+ return 0;
+
+error:
+ SetPageError(page);
+ unlock_page(page);
+ return -EIO;
+}
+
+static void *nfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ struct inode *inode = d_inode(dentry);
+ struct page *page;
+ void *err;
+
+ err = ERR_PTR(nfs_revalidate_mapping(inode, inode->i_mapping));
+ if (err)
+ goto read_failed;
+ page = read_cache_page(&inode->i_data, 0,
+ (filler_t *)nfs_symlink_filler, inode);
+ if (IS_ERR(page)) {
+ err = page;
+ goto read_failed;
+ }
+ nd_set_link(nd, kmap(page));
+ return page;
+
+read_failed:
+ nd_set_link(nd, err);
+ return NULL;
+}
+
+/*
+ * symlinks can't do much...
+ */
+const struct inode_operations nfs_symlink_inode_operations = {
+ .readlink = generic_readlink,
+ .follow_link = nfs_follow_link,
+ .put_link = page_put_link,
+ .getattr = nfs_getattr,
+ .setattr = nfs_setattr,
+};