mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 23:46:42 +07:00
32fb378437
Pull vfs RCU symlink updates from Al Viro: "Replacement of ->follow_link/->put_link, allowing to stay in RCU mode even if the symlink is not an embedded one. No changes since the mailbomb on Jan 1" * 'work.symlinks' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: switch ->get_link() to delayed_call, kill ->put_link() kill free_page_put_link() teach nfs_get_link() to work in RCU mode teach proc_self_get_link()/proc_thread_self_get_link() to work in RCU mode teach shmem_get_link() to work in RCU mode teach page_get_link() to work in RCU mode replace ->follow_link() with new method that could stay in RCU mode don't put symlink bodies in pagecache into highmem namei: page_getlink() and page_follow_link_light() are the same thing ufs: get rid of ->setattr() for symlinks udf: don't duplicate page_symlink_inode_operations logfs: don't duplicate page_symlink_inode_operations switch befs long symlinks to page_symlink_operations
123 lines
3.0 KiB
C
123 lines
3.0 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"
|
|
|
|
#ifdef CONFIG_EXT4_FS_ENCRYPTION
|
|
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 ext4_str cstr, pstr;
|
|
struct ext4_encrypted_symlink_data *sd;
|
|
loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1);
|
|
int res;
|
|
u32 plen, max_size = inode->i_sb->s_blocksize;
|
|
|
|
if (!dentry)
|
|
return ERR_PTR(-ECHILD);
|
|
|
|
res = ext4_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);
|
|
caddr[size] = 0;
|
|
}
|
|
|
|
/* Symlink is encrypted */
|
|
sd = (struct ext4_encrypted_symlink_data *)caddr;
|
|
cstr.name = sd->encrypted_path;
|
|
cstr.len = le16_to_cpu(sd->len);
|
|
if ((cstr.len +
|
|
sizeof(struct ext4_encrypted_symlink_data) - 1) >
|
|
max_size) {
|
|
/* Symlink data on the disk is corrupted */
|
|
res = -EFSCORRUPTED;
|
|
goto errout;
|
|
}
|
|
plen = (cstr.len < EXT4_FNAME_CRYPTO_DIGEST_SIZE*2) ?
|
|
EXT4_FNAME_CRYPTO_DIGEST_SIZE*2 : cstr.len;
|
|
paddr = kmalloc(plen + 1, GFP_NOFS);
|
|
if (!paddr) {
|
|
res = -ENOMEM;
|
|
goto errout;
|
|
}
|
|
pstr.name = paddr;
|
|
pstr.len = plen;
|
|
res = _ext4_fname_disk_to_usr(inode, NULL, &cstr, &pstr);
|
|
if (res < 0)
|
|
goto errout;
|
|
/* Null-terminate the name */
|
|
if (res <= plen)
|
|
paddr[res] = '\0';
|
|
if (cpage)
|
|
page_cache_release(cpage);
|
|
set_delayed_call(done, kfree_link, paddr);
|
|
return paddr;
|
|
errout:
|
|
if (cpage)
|
|
page_cache_release(cpage);
|
|
kfree(paddr);
|
|
return ERR_PTR(res);
|
|
}
|
|
|
|
const struct inode_operations ext4_encrypted_symlink_inode_operations = {
|
|
.readlink = generic_readlink,
|
|
.get_link = ext4_encrypted_get_link,
|
|
.setattr = ext4_setattr,
|
|
.setxattr = generic_setxattr,
|
|
.getxattr = generic_getxattr,
|
|
.listxattr = ext4_listxattr,
|
|
.removexattr = generic_removexattr,
|
|
};
|
|
#endif
|
|
|
|
const struct inode_operations ext4_symlink_inode_operations = {
|
|
.readlink = generic_readlink,
|
|
.get_link = page_get_link,
|
|
.setattr = ext4_setattr,
|
|
.setxattr = generic_setxattr,
|
|
.getxattr = generic_getxattr,
|
|
.listxattr = ext4_listxattr,
|
|
.removexattr = generic_removexattr,
|
|
};
|
|
|
|
const struct inode_operations ext4_fast_symlink_inode_operations = {
|
|
.readlink = generic_readlink,
|
|
.get_link = simple_get_link,
|
|
.setattr = ext4_setattr,
|
|
.setxattr = generic_setxattr,
|
|
.getxattr = generic_getxattr,
|
|
.listxattr = ext4_listxattr,
|
|
.removexattr = generic_removexattr,
|
|
};
|