Contributors: 39
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Tejun Heo |
647 |
35.69% |
18 |
18.00% |
| Andreas Gruenbacher |
214 |
11.80% |
2 |
2.00% |
| Christian Brauner |
173 |
9.54% |
13 |
13.00% |
| Maneesh Soni |
135 |
7.45% |
2 |
2.00% |
| Eric W. Biedermann |
90 |
4.96% |
8 |
8.00% |
| Ondrej Mosnáček |
89 |
4.91% |
4 |
4.00% |
| Daniel Xu |
66 |
3.64% |
1 |
1.00% |
| Casey Schaufler |
56 |
3.09% |
2 |
2.00% |
| MinChan Kim |
46 |
2.54% |
1 |
1.00% |
| Ian Kent |
32 |
1.77% |
2 |
2.00% |
| Patrick Mochel |
31 |
1.71% |
4 |
4.00% |
| Hugh Dickins |
24 |
1.32% |
1 |
1.00% |
| David P. Quigley |
23 |
1.27% |
1 |
1.00% |
| David Howells |
21 |
1.16% |
3 |
3.00% |
| Al Viro |
20 |
1.10% |
2 |
2.00% |
| Jeff Layton |
15 |
0.83% |
3 |
3.00% |
| Shaohua Li |
15 |
0.83% |
2 |
2.00% |
| Serge E. Hallyn |
14 |
0.77% |
1 |
1.00% |
| Nicholas Piggin |
14 |
0.77% |
3 |
3.00% |
| Greg Kroah-Hartman |
11 |
0.61% |
1 |
1.00% |
| Deepa Dinamani |
11 |
0.61% |
2 |
2.00% |
| T.J. Mercier |
9 |
0.50% |
1 |
1.00% |
| Khan, Imran |
8 |
0.44% |
1 |
1.00% |
| Linus Torvalds (pre-git) |
7 |
0.39% |
3 |
3.00% |
| Stephen D. Smalley |
6 |
0.33% |
1 |
1.00% |
| Ming Lei |
6 |
0.33% |
1 |
1.00% |
| Randy Dunlap |
5 |
0.28% |
2 |
2.00% |
| James Morris |
4 |
0.22% |
1 |
1.00% |
| Jan Kara |
3 |
0.17% |
2 |
2.00% |
| Andrew Morton |
3 |
0.17% |
2 |
2.00% |
| Mateusz Guzik |
3 |
0.17% |
1 |
1.00% |
| Bart Van Assche |
2 |
0.11% |
1 |
1.00% |
| Thomas Gleixner |
2 |
0.11% |
1 |
1.00% |
| Ayush Mittal |
2 |
0.11% |
1 |
1.00% |
| Christoph Hellwig |
2 |
0.11% |
2 |
2.00% |
| Johannes Weiner |
1 |
0.06% |
1 |
1.00% |
| Arjan van de Ven |
1 |
0.06% |
1 |
1.00% |
| Wedson Almeida Filho |
1 |
0.06% |
1 |
1.00% |
| Linus Torvalds |
1 |
0.06% |
1 |
1.00% |
| Total |
1813 |
|
100 |
|
// 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, bool alloc)
{
struct kernfs_iattrs *ret __free(kfree) = NULL;
struct kernfs_iattrs *attr;
attr = READ_ONCE(kn->iattr);
if (attr || !alloc)
return attr;
ret = kmem_cache_zalloc(kernfs_iattrs_cache, GFP_KERNEL);
if (!ret)
return NULL;
/* assign default attributes */
ret->ia_uid = GLOBAL_ROOT_UID;
ret->ia_gid = GLOBAL_ROOT_GID;
ktime_get_real_ts64(&ret->ia_atime);
ret->ia_mtime = ret->ia_atime;
ret->ia_ctime = ret->ia_atime;
simple_xattr_limits_init(&ret->xattr_limits);
/* If someone raced us, recognize it. */
if (!try_cmpxchg(&kn->iattr, &attr, ret))
return READ_ONCE(kn->iattr);
return no_free_ptr(ret);
}
static struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
{
return __kernfs_iattrs(kn, true);
}
static struct kernfs_iattrs *kernfs_iattrs_noalloc(struct kernfs_node *kn)
{
return __kernfs_iattrs(kn, false);
}
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), READ_ONCE(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;
inode->i_mode = kn->mode;
attrs = kernfs_iattrs_noalloc(kn);
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 && !(kn->flags & KERNFS_REMOVING))
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_state_read_once(inode) & 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);
struct simple_xattrs *xattrs;
if (!attrs)
return -ENODATA;
xattrs = READ_ONCE(attrs->xattrs);
if (!xattrs)
return -ENODATA;
return simple_xattr_get(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 simple_xattrs *xattrs;
struct kernfs_iattrs *attrs;
attrs = kernfs_iattrs(kn);
if (!attrs)
return -ENOMEM;
xattrs = simple_xattrs_lazy_alloc(&attrs->xattrs, value, flags);
if (IS_ERR_OR_NULL(xattrs))
return PTR_ERR(xattrs);
old_xattr = simple_xattr_set(xattrs, name, value, size, flags);
if (IS_ERR(old_xattr))
return PTR_ERR(old_xattr);
simple_xattr_free_rcu(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_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 simple_xattrs *xattrs;
struct kernfs_iattrs *attrs;
if (!(kernfs_root(kn)->flags & KERNFS_ROOT_SUPPORT_USER_XATTR))
return -EOPNOTSUPP;
attrs = kernfs_iattrs(kn);
if (!attrs)
return -ENOMEM;
xattrs = simple_xattrs_lazy_alloc(&attrs->xattrs, value, flags);
if (IS_ERR_OR_NULL(xattrs))
return PTR_ERR(xattrs);
return simple_xattr_set_limited(xattrs, &attrs->xattr_limits,
full_name, 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
};