mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-17 09:14:19 +08:00
99652ea56a
Return enhanced file attributes from the Ext4 filesystem. This includes the following: (1) The inode creation time (i_crtime) as stx_btime, setting STATX_BTIME. (2) Certain FS_xxx_FL flags are mapped to stx_attribute flags. This requires that all ext4 inodes have a getattr call, not just some of them, so to this end, split the ext4_getattr() function and only call part of it where appropriate. Example output: [root@andromeda ~]# touch foo [root@andromeda ~]# chattr +ai foo [root@andromeda ~]# /tmp/test-statx foo statx(foo) = 0 results=fff Size: 0 Blocks: 0 IO Block: 4096 regular file Device: 08:12 Inode: 2101950 Links: 1 Access: (0644/-rw-r--r--) Uid: 0 Gid: 0 Access: 2016-02-11 17:08:29.031795451+0000 Modify: 2016-02-11 17:08:29.031795451+0000 Change: 2016-02-11 17:11:11.987790114+0000 Birth: 2016-02-11 17:08:29.031795451+0000 Attributes: 0000000000000030 (-------- -------- -------- -------- -------- -------- -------- --ai----) Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
105 lines
2.4 KiB
C
105 lines
2.4 KiB
C
/*
|
|
* linux/fs/ext4/symlink.c
|
|
*
|
|
* Only fast symlinks left here - the rest is done by generic code. AV, 1999
|
|
*
|
|
* Copyright (C) 1992, 1993, 1994, 1995
|
|
* Remy Card (card@masi.ibp.fr)
|
|
* Laboratoire MASI - Institut Blaise Pascal
|
|
* Universite Pierre et Marie Curie (Paris VI)
|
|
*
|
|
* from
|
|
*
|
|
* linux/fs/minix/symlink.c
|
|
*
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
*
|
|
* ext4 symlink handling code
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/namei.h>
|
|
#include "ext4.h"
|
|
#include "xattr.h"
|
|
|
|
static const char *ext4_encrypted_get_link(struct dentry *dentry,
|
|
struct inode *inode,
|
|
struct delayed_call *done)
|
|
{
|
|
struct page *cpage = NULL;
|
|
char *caddr, *paddr = NULL;
|
|
struct fscrypt_str cstr, pstr;
|
|
struct fscrypt_symlink_data *sd;
|
|
int res;
|
|
u32 max_size = inode->i_sb->s_blocksize;
|
|
|
|
if (!dentry)
|
|
return ERR_PTR(-ECHILD);
|
|
|
|
res = fscrypt_get_encryption_info(inode);
|
|
if (res)
|
|
return ERR_PTR(res);
|
|
|
|
if (ext4_inode_is_fast_symlink(inode)) {
|
|
caddr = (char *) EXT4_I(inode)->i_data;
|
|
max_size = sizeof(EXT4_I(inode)->i_data);
|
|
} else {
|
|
cpage = read_mapping_page(inode->i_mapping, 0, NULL);
|
|
if (IS_ERR(cpage))
|
|
return ERR_CAST(cpage);
|
|
caddr = page_address(cpage);
|
|
}
|
|
|
|
/* Symlink is encrypted */
|
|
sd = (struct fscrypt_symlink_data *)caddr;
|
|
cstr.name = sd->encrypted_path;
|
|
cstr.len = le16_to_cpu(sd->len);
|
|
if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) {
|
|
/* Symlink data on the disk is corrupted */
|
|
res = -EFSCORRUPTED;
|
|
goto errout;
|
|
}
|
|
|
|
res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr);
|
|
if (res)
|
|
goto errout;
|
|
paddr = pstr.name;
|
|
|
|
res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
|
|
if (res)
|
|
goto errout;
|
|
|
|
/* Null-terminate the name */
|
|
paddr[pstr.len] = '\0';
|
|
if (cpage)
|
|
put_page(cpage);
|
|
set_delayed_call(done, kfree_link, paddr);
|
|
return paddr;
|
|
errout:
|
|
if (cpage)
|
|
put_page(cpage);
|
|
kfree(paddr);
|
|
return ERR_PTR(res);
|
|
}
|
|
|
|
const struct inode_operations ext4_encrypted_symlink_inode_operations = {
|
|
.get_link = ext4_encrypted_get_link,
|
|
.setattr = ext4_setattr,
|
|
.getattr = ext4_getattr,
|
|
.listxattr = ext4_listxattr,
|
|
};
|
|
|
|
const struct inode_operations ext4_symlink_inode_operations = {
|
|
.get_link = page_get_link,
|
|
.setattr = ext4_setattr,
|
|
.getattr = ext4_getattr,
|
|
.listxattr = ext4_listxattr,
|
|
};
|
|
|
|
const struct inode_operations ext4_fast_symlink_inode_operations = {
|
|
.get_link = simple_get_link,
|
|
.setattr = ext4_setattr,
|
|
.getattr = ext4_getattr,
|
|
.listxattr = ext4_listxattr,
|
|
};
|