2 * linux/fs/ext4/symlink.c
4 * Only fast symlinks left here - the rest is done by generic code. AV, 1999
6 * Copyright (C) 1992, 1993, 1994, 1995
8 * Laboratoire MASI - Institut Blaise Pascal
9 * Universite Pierre et Marie Curie (Paris VI)
13 * linux/fs/minix/symlink.c
15 * Copyright (C) 1991, 1992 Linus Torvalds
17 * ext4 symlink handling code
21 #include <linux/namei.h>
25 #ifdef CONFIG_EXT4_FS_ENCRYPTION
26 static const char *ext4_encrypted_get_link(struct dentry *dentry,
28 struct delayed_call *done)
30 struct page *cpage = NULL;
31 char *caddr, *paddr = NULL;
32 struct ext4_str cstr, pstr;
33 struct ext4_encrypted_symlink_data *sd;
34 loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1);
36 u32 plen, max_size = inode->i_sb->s_blocksize;
39 return ERR_PTR(-ECHILD);
41 res = ext4_get_encryption_info(inode);
45 if (ext4_inode_is_fast_symlink(inode)) {
46 caddr = (char *) EXT4_I(inode)->i_data;
47 max_size = sizeof(EXT4_I(inode)->i_data);
49 cpage = read_mapping_page(inode->i_mapping, 0, NULL);
51 return ERR_CAST(cpage);
52 caddr = page_address(cpage);
56 /* Symlink is encrypted */
57 sd = (struct ext4_encrypted_symlink_data *)caddr;
58 cstr.name = sd->encrypted_path;
59 cstr.len = le16_to_cpu(sd->len);
61 sizeof(struct ext4_encrypted_symlink_data) - 1) >
63 /* Symlink data on the disk is corrupted */
67 plen = (cstr.len < EXT4_FNAME_CRYPTO_DIGEST_SIZE*2) ?
68 EXT4_FNAME_CRYPTO_DIGEST_SIZE*2 : cstr.len;
69 paddr = kmalloc(plen + 1, GFP_NOFS);
76 res = _ext4_fname_disk_to_usr(inode, NULL, &cstr, &pstr);
79 /* Null-terminate the name */
84 set_delayed_call(done, kfree_link, paddr);
93 const struct inode_operations ext4_encrypted_symlink_inode_operations = {
94 .readlink = generic_readlink,
95 .get_link = ext4_encrypted_get_link,
96 .setattr = ext4_setattr,
97 .setxattr = generic_setxattr,
98 .getxattr = generic_getxattr,
99 .listxattr = ext4_listxattr,
100 .removexattr = generic_removexattr,
104 const struct inode_operations ext4_symlink_inode_operations = {
105 .readlink = generic_readlink,
106 .get_link = page_get_link,
107 .setattr = ext4_setattr,
108 .setxattr = generic_setxattr,
109 .getxattr = generic_getxattr,
110 .listxattr = ext4_listxattr,
111 .removexattr = generic_removexattr,
114 const struct inode_operations ext4_fast_symlink_inode_operations = {
115 .readlink = generic_readlink,
116 .get_link = simple_get_link,
117 .setattr = ext4_setattr,
118 .setxattr = generic_setxattr,
119 .getxattr = generic_getxattr,
120 .listxattr = ext4_listxattr,
121 .removexattr = generic_removexattr,