Contributors: 37
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Tejun Heo |
712 |
34.60% |
18 |
19.35% |
| Daniel Xu |
278 |
13.51% |
1 |
1.08% |
| Andreas Gruenbacher |
203 |
9.86% |
2 |
2.15% |
| Maneesh Soni |
135 |
6.56% |
2 |
2.15% |
| Ondrej Mosnáček |
113 |
5.49% |
4 |
4.30% |
| Eric W. Biedermann |
90 |
4.37% |
8 |
8.60% |
| Hugh Dickins |
86 |
4.18% |
1 |
1.08% |
| Casey Schaufler |
75 |
3.64% |
1 |
1.08% |
| MinChan Kim |
46 |
2.24% |
1 |
1.08% |
| David P. Quigley |
42 |
2.04% |
1 |
1.08% |
| Christian Brauner |
37 |
1.80% |
9 |
9.68% |
| Patrick Mochel |
32 |
1.55% |
4 |
4.30% |
| Ian Kent |
32 |
1.55% |
2 |
2.15% |
| David Howells |
23 |
1.12% |
3 |
3.23% |
| Al Viro |
20 |
0.97% |
2 |
2.15% |
| Jeff Layton |
15 |
0.73% |
3 |
3.23% |
| Shaohua Li |
15 |
0.73% |
2 |
2.15% |
| Serge E. Hallyn |
14 |
0.68% |
1 |
1.08% |
| Nicholas Piggin |
14 |
0.68% |
3 |
3.23% |
| Deepa Dinamani |
11 |
0.53% |
2 |
2.15% |
| Greg Kroah-Hartman |
11 |
0.53% |
1 |
1.08% |
| Khan, Imran |
8 |
0.39% |
1 |
1.08% |
| Linus Torvalds (pre-git) |
7 |
0.34% |
3 |
3.23% |
| Stephen D. Smalley |
6 |
0.29% |
1 |
1.08% |
| Ming Lei |
6 |
0.29% |
1 |
1.08% |
| Randy Dunlap |
5 |
0.24% |
2 |
2.15% |
| James Morris |
4 |
0.19% |
1 |
1.08% |
| Andrew Morton |
3 |
0.15% |
2 |
2.15% |
| Jan Kara |
3 |
0.15% |
2 |
2.15% |
| Christoph Hellwig |
2 |
0.10% |
2 |
2.15% |
| Bart Van Assche |
2 |
0.10% |
1 |
1.08% |
| Thomas Gleixner |
2 |
0.10% |
1 |
1.08% |
| Ayush Mittal |
2 |
0.10% |
1 |
1.08% |
| Linus Torvalds |
1 |
0.05% |
1 |
1.08% |
| Arjan van de Ven |
1 |
0.05% |
1 |
1.08% |
| Johannes Weiner |
1 |
0.05% |
1 |
1.08% |
| Wedson Almeida Filho |
1 |
0.05% |
1 |
1.08% |
| Total |
2058 |
|
93 |
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* fs/kernfs/inode.c - kernfs inode implementation
*
* Copyright (c) 2001-3 Patrick Mochel
* Copyright (c) 2007 SUSE Linux Products GmbH
* Copyright (c) 2007, 2013 Tejun Heo <tj@kernel.org>
*/
#include <linux/pagemap.h>
#include <linux/backing-dev.h>
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/xattr.h>
#include <linux/security.h>
#include "kernfs-internal.h"
static const struct inode_operations kernfs_iops = {
.permission = kernfs_iop_permission,
.setattr = kernfs_iop_setattr,
.getattr = kernfs_iop_getattr,
.listxattr = kernfs_iop_listxattr,
};
static struct kernfs_iattrs *__kernfs_iattrs(struct kernfs_node *kn, int alloc)
{
static DEFINE_MUTEX(iattr_mutex);
struct kernfs_iattrs *ret;
mutex_lock(&iattr_mutex);
if (kn->iattr || !alloc)
goto out_unlock;
kn->iattr = kmem_cache_zalloc(kernfs_iattrs_cache, GFP_KERNEL);
if (!kn->iattr)
goto out_unlock;
/* assign default attributes */
kn->iattr->ia_uid = GLOBAL_ROOT_UID;
kn->iattr->ia_gid = GLOBAL_ROOT_GID;
ktime_get_real_ts64(&kn->iattr->ia_atime);
kn->iattr->ia_mtime = kn->iattr->ia_atime;
kn->iattr->ia_ctime = kn->iattr->ia_atime;
simple_xattrs_init(&kn->iattr->xattrs);
atomic_set(&kn->iattr->nr_user_xattrs, 0);
atomic_set(&kn->iattr->user_xattr_size, 0);
out_unlock:
ret = kn->iattr;
mutex_unlock(&iattr_mutex);
return ret;
}
static struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
{
return __kernfs_iattrs(kn, 1);
}
static struct kernfs_iattrs *kernfs_iattrs_noalloc(struct kernfs_node *kn)
{
return __kernfs_iattrs(kn, 0);
}
int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr)
{
struct kernfs_iattrs *attrs;
unsigned int ia_valid = iattr->ia_valid;
attrs = kernfs_iattrs(kn);
if (!attrs)
return -ENOMEM;
if (ia_valid & ATTR_UID)
attrs->ia_uid = iattr->ia_uid;
if (ia_valid & ATTR_GID)
attrs->ia_gid = iattr->ia_gid;
if (ia_valid & ATTR_ATIME)
attrs->ia_atime = iattr->ia_atime;
if (ia_valid & ATTR_MTIME)
attrs->ia_mtime = iattr->ia_mtime;
if (ia_valid & ATTR_CTIME)
attrs->ia_ctime = iattr->ia_ctime;
if (ia_valid & ATTR_MODE)
kn->mode = iattr->ia_mode;
return 0;
}
/**
* kernfs_setattr - set iattr on a node
* @kn: target node
* @iattr: iattr to set
*
* Return: %0 on success, -errno on failure.
*/
int kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr)
{
int ret;
struct kernfs_root *root = kernfs_root(kn);
down_write(&root->kernfs_iattr_rwsem);
ret = __kernfs_setattr(kn, iattr);
up_write(&root->kernfs_iattr_rwsem);
return ret;
}
int kernfs_iop_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
struct iattr *iattr)
{
struct inode *inode = d_inode(dentry);
struct kernfs_node *kn = inode->i_private;
struct kernfs_root *root;
int error;
if (!kn)
return -EINVAL;
root = kernfs_root(kn);
down_write(&root->kernfs_iattr_rwsem);
error = setattr_prepare(&nop_mnt_idmap, dentry, iattr);
if (error)
goto out;
error = __kernfs_setattr(kn, iattr);
if (error)
goto out;
/* this ignores size changes */
setattr_copy(&nop_mnt_idmap, inode, iattr);
out:
up_write(&root->kernfs_iattr_rwsem);
return error;
}
ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size)
{
struct kernfs_node *kn = kernfs_dentry_node(dentry);
struct kernfs_iattrs *attrs;
attrs = kernfs_iattrs(kn);
if (!attrs)
return -ENOMEM;
return simple_xattr_list(d_inode(dentry), &attrs->xattrs, buf, size);
}
static inline void set_default_inode_attr(struct inode *inode, umode_t mode)
{
inode->i_mode = mode;
simple_inode_init_ts(inode);
}
static inline void set_inode_attr(struct inode *inode,
struct kernfs_iattrs *attrs)
{
inode->i_uid = attrs->ia_uid;
inode->i_gid = attrs->ia_gid;
inode_set_atime_to_ts(inode, attrs->ia_atime);
inode_set_mtime_to_ts(inode, attrs->ia_mtime);
inode_set_ctime_to_ts(inode, attrs->ia_ctime);
}
static void kernfs_refresh_inode(struct kernfs_node *kn, struct inode *inode)
{
struct kernfs_iattrs *attrs = kn->iattr;
inode->i_mode = kn->mode;
if (attrs)
/*
* kernfs_node has non-default attributes get them from
* persistent copy in kernfs_node.
*/
set_inode_attr(inode, attrs);
if (kernfs_type(kn) == KERNFS_DIR)
set_nlink(inode, kn->dir.subdirs + 2);
}
int kernfs_iop_getattr(struct mnt_idmap *idmap,
const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
{
struct inode *inode = d_inode(path->dentry);
struct kernfs_node *kn = inode->i_private;
struct kernfs_root *root = kernfs_root(kn);
down_read(&root->kernfs_iattr_rwsem);
kernfs_refresh_inode(kn, inode);
generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
up_read(&root->kernfs_iattr_rwsem);
return 0;
}
static void kernfs_init_inode(struct kernfs_node *kn, struct inode *inode)
{
kernfs_get(kn);
inode->i_private = kn;
inode->i_mapping->a_ops = &ram_aops;
inode->i_op = &kernfs_iops;
inode->i_generation = kernfs_gen(kn);
set_default_inode_attr(inode, kn->mode);
kernfs_refresh_inode(kn, inode);
/* initialize inode according to type */
switch (kernfs_type(kn)) {
case KERNFS_DIR:
inode->i_op = &kernfs_dir_iops;
inode->i_fop = &kernfs_dir_fops;
if (kn->flags & KERNFS_EMPTY_DIR)
make_empty_dir_inode(inode);
break;
case KERNFS_FILE:
inode->i_size = kn->attr.size;
inode->i_fop = &kernfs_file_fops;
break;
case KERNFS_LINK:
inode->i_op = &kernfs_symlink_iops;
break;
default:
BUG();
}
unlock_new_inode(inode);
}
/**
* kernfs_get_inode - get inode for kernfs_node
* @sb: super block
* @kn: kernfs_node to allocate inode for
*
* Get inode for @kn. If such inode doesn't exist, a new inode is
* allocated and basics are initialized. New inode is returned
* locked.
*
* Locking:
* Kernel thread context (may sleep).
*
* Return:
* Pointer to allocated inode on success, %NULL on failure.
*/
struct inode *kernfs_get_inode(struct super_block *sb, struct kernfs_node *kn)
{
struct inode *inode;
inode = iget_locked(sb, kernfs_ino(kn));
if (inode && (inode->i_state & I_NEW))
kernfs_init_inode(kn, inode);
return inode;
}
/*
* The kernfs_node serves as both an inode and a directory entry for
* kernfs. To prevent the kernfs inode numbers from being freed
* prematurely we take a reference to kernfs_node from the kernfs inode. A
* super_operations.evict_inode() implementation is needed to drop that
* reference upon inode destruction.
*/
void kernfs_evict_inode(struct inode *inode)
{
struct kernfs_node *kn = inode->i_private;
truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
kernfs_put(kn);
}
int kernfs_iop_permission(struct mnt_idmap *idmap,
struct inode *inode, int mask)
{
struct kernfs_node *kn;
struct kernfs_root *root;
int ret;
if (mask & MAY_NOT_BLOCK)
return -ECHILD;
kn = inode->i_private;
root = kernfs_root(kn);
down_read(&root->kernfs_iattr_rwsem);
kernfs_refresh_inode(kn, inode);
ret = generic_permission(&nop_mnt_idmap, inode, mask);
up_read(&root->kernfs_iattr_rwsem);
return ret;
}
int kernfs_xattr_get(struct kernfs_node *kn, const char *name,
void *value, size_t size)
{
struct kernfs_iattrs *attrs = kernfs_iattrs_noalloc(kn);
if (!attrs)
return -ENODATA;
return simple_xattr_get(&attrs->xattrs, name, value, size);
}
int kernfs_xattr_set(struct kernfs_node *kn, const char *name,
const void *value, size_t size, int flags)
{
struct simple_xattr *old_xattr;
struct kernfs_iattrs *attrs = kernfs_iattrs(kn);
if (!attrs)
return -ENOMEM;
old_xattr = simple_xattr_set(&attrs->xattrs, name, value, size, flags);
if (IS_ERR(old_xattr))
return PTR_ERR(old_xattr);
simple_xattr_free(old_xattr);
return 0;
}
static int kernfs_vfs_xattr_get(const struct xattr_handler *handler,
struct dentry *unused, struct inode *inode,
const char *suffix, void *value, size_t size)
{
const char *name = xattr_full_name(handler, suffix);
struct kernfs_node *kn = inode->i_private;
return kernfs_xattr_get(kn, name, value, size);
}
static int kernfs_vfs_xattr_set(const struct xattr_handler *handler,
struct mnt_idmap *idmap,
struct dentry *unused, struct inode *inode,
const char *suffix, const void *value,
size_t size, int flags)
{
const char *name = xattr_full_name(handler, suffix);
struct kernfs_node *kn = inode->i_private;
return kernfs_xattr_set(kn, name, value, size, flags);
}
static int kernfs_vfs_user_xattr_add(struct kernfs_node *kn,
const char *full_name,
struct simple_xattrs *xattrs,
const void *value, size_t size, int flags)
{
atomic_t *sz = &kn->iattr->user_xattr_size;
atomic_t *nr = &kn->iattr->nr_user_xattrs;
struct simple_xattr *old_xattr;
int ret;
if (atomic_inc_return(nr) > KERNFS_MAX_USER_XATTRS) {
ret = -ENOSPC;
goto dec_count_out;
}
if (atomic_add_return(size, sz) > KERNFS_USER_XATTR_SIZE_LIMIT) {
ret = -ENOSPC;
goto dec_size_out;
}
old_xattr = simple_xattr_set(xattrs, full_name, value, size, flags);
if (!old_xattr)
return 0;
if (IS_ERR(old_xattr)) {
ret = PTR_ERR(old_xattr);
goto dec_size_out;
}
ret = 0;
size = old_xattr->size;
simple_xattr_free(old_xattr);
dec_size_out:
atomic_sub(size, sz);
dec_count_out:
atomic_dec(nr);
return ret;
}
static int kernfs_vfs_user_xattr_rm(struct kernfs_node *kn,
const char *full_name,
struct simple_xattrs *xattrs,
const void *value, size_t size, int flags)
{
atomic_t *sz = &kn->iattr->user_xattr_size;
atomic_t *nr = &kn->iattr->nr_user_xattrs;
struct simple_xattr *old_xattr;
old_xattr = simple_xattr_set(xattrs, full_name, value, size, flags);
if (!old_xattr)
return 0;
if (IS_ERR(old_xattr))
return PTR_ERR(old_xattr);
atomic_sub(old_xattr->size, sz);
atomic_dec(nr);
simple_xattr_free(old_xattr);
return 0;
}
static int kernfs_vfs_user_xattr_set(const struct xattr_handler *handler,
struct mnt_idmap *idmap,
struct dentry *unused, struct inode *inode,
const char *suffix, const void *value,
size_t size, int flags)
{
const char *full_name = xattr_full_name(handler, suffix);
struct kernfs_node *kn = inode->i_private;
struct kernfs_iattrs *attrs;
if (!(kernfs_root(kn)->flags & KERNFS_ROOT_SUPPORT_USER_XATTR))
return -EOPNOTSUPP;
attrs = kernfs_iattrs(kn);
if (!attrs)
return -ENOMEM;
if (value)
return kernfs_vfs_user_xattr_add(kn, full_name, &attrs->xattrs,
value, size, flags);
else
return kernfs_vfs_user_xattr_rm(kn, full_name, &attrs->xattrs,
value, size, flags);
}
static const struct xattr_handler kernfs_trusted_xattr_handler = {
.prefix = XATTR_TRUSTED_PREFIX,
.get = kernfs_vfs_xattr_get,
.set = kernfs_vfs_xattr_set,
};
static const struct xattr_handler kernfs_security_xattr_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.get = kernfs_vfs_xattr_get,
.set = kernfs_vfs_xattr_set,
};
static const struct xattr_handler kernfs_user_xattr_handler = {
.prefix = XATTR_USER_PREFIX,
.get = kernfs_vfs_xattr_get,
.set = kernfs_vfs_user_xattr_set,
};
const struct xattr_handler * const kernfs_xattr_handlers[] = {
&kernfs_trusted_xattr_handler,
&kernfs_security_xattr_handler,
&kernfs_user_xattr_handler,
NULL
};