blob: 5e2cbfdab6fc0d6b96a19c321a9208dda8cd130d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/ipc/shm.c
3 * Copyright (C) 1992, 1993 Krishna Balasubramanian
4 * Many improvements/fixes by Bruno Haible.
5 * Replaced `struct shm_desc' by `struct vm_area_struct', July 1994.
6 * Fixed the shm swap deallocation (shm_unuse()), August 1998 Andrea Arcangeli.
7 *
8 * /proc/sysvipc/shm support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
9 * BIGMEM support, Andrea Arcangeli <andrea@suse.de>
10 * SMP thread shm, Jean-Luc Boyard <jean-luc.boyard@siemens.fr>
11 * HIGHMEM support, Ingo Molnar <mingo@redhat.com>
12 * Make shmmax, shmall, shmmni sysctl'able, Christoph Rohland <cr@sap.com>
13 * Shared /dev/zero support, Kanoj Sarcar <kanoj@sgi.com>
14 * Move the mm functionality over to mm/shmem.c, Christoph Rohland <cr@sap.com>
15 *
Steve Grubb073115d2006-04-02 17:07:33 -040016 * support for audit of ipc object properties and permission changes
17 * Dustin Kirkland <dustin.kirkland@us.ibm.com>
Kirill Korotaev4e982312006-10-02 02:18:22 -070018 *
19 * namespaces support
20 * OpenVZ, SWsoft Inc.
21 * Pavel Emelianov <xemul@openvz.org>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 */
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/slab.h>
25#include <linux/mm.h>
26#include <linux/hugetlb.h>
27#include <linux/shm.h>
28#include <linux/init.h>
29#include <linux/file.h>
30#include <linux/mman.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <linux/shmem_fs.h>
32#include <linux/security.h>
33#include <linux/syscalls.h>
34#include <linux/audit.h>
Randy.Dunlapc59ede72006-01-11 12:17:46 -080035#include <linux/capability.h>
Stephen Rothwell7d87e14c2005-05-01 08:59:12 -070036#include <linux/ptrace.h>
Mike Waychison19b49462005-09-06 15:17:10 -070037#include <linux/seq_file.h>
Nadia Derbey3e148c72007-10-18 23:40:54 -070038#include <linux/rwsem.h>
Kirill Korotaev4e982312006-10-02 02:18:22 -070039#include <linux/nsproxy.h>
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -080040#include <linux/mount.h>
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -080041#include <linux/ipc_namespace.h>
Stephen Rothwell7d87e14c2005-05-01 08:59:12 -070042
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#include <asm/uaccess.h>
44
45#include "util.h"
46
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -080047struct shm_file_data {
48 int id;
49 struct ipc_namespace *ns;
50 struct file *file;
51 const struct vm_operations_struct *vm_ops;
52};
53
54#define shm_file_data(file) (*((struct shm_file_data **)&(file)->private_data))
55
Arjan van de Ven9a321442007-02-12 00:55:35 -080056static const struct file_operations shm_file_operations;
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +040057static const struct vm_operations_struct shm_vm_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
Pierre Peiffered2ddbf2008-02-08 04:18:57 -080059#define shm_ids(ns) ((ns)->ids[IPC_SHM_IDS])
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
Kirill Korotaev4e982312006-10-02 02:18:22 -070061#define shm_unlock(shp) \
62 ipc_unlock(&(shp)->shm_perm)
Kirill Korotaev4e982312006-10-02 02:18:22 -070063
Nadia Derbey7748dbf2007-10-18 23:40:49 -070064static int newseg(struct ipc_namespace *, struct ipc_params *);
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -080065static void shm_open(struct vm_area_struct *vma);
66static void shm_close(struct vm_area_struct *vma);
Kirill Korotaev4e982312006-10-02 02:18:22 -070067static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068#ifdef CONFIG_PROC_FS
Mike Waychison19b49462005-09-06 15:17:10 -070069static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
Linus Torvalds1da177e2005-04-16 15:20:36 -070070#endif
71
Pierre Peiffered2ddbf2008-02-08 04:18:57 -080072void shm_init_ns(struct ipc_namespace *ns)
Kirill Korotaev4e982312006-10-02 02:18:22 -070073{
Kirill Korotaev4e982312006-10-02 02:18:22 -070074 ns->shm_ctlmax = SHMMAX;
75 ns->shm_ctlall = SHMALL;
76 ns->shm_ctlmni = SHMMNI;
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -070077 ns->shm_rmid_forced = 0;
Kirill Korotaev4e982312006-10-02 02:18:22 -070078 ns->shm_tot = 0;
WANG Conge8148f72009-01-06 14:42:49 -080079 ipc_init_ids(&shm_ids(ns));
Kirill Korotaev4e982312006-10-02 02:18:22 -070080}
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
Nadia Derbeyf4566f02007-10-18 23:40:53 -070082/*
Nadia Derbey3e148c72007-10-18 23:40:54 -070083 * Called with shm_ids.rw_mutex (writer) and the shp structure locked.
84 * Only shm_ids.rw_mutex remains locked on exit.
Nadia Derbeyf4566f02007-10-18 23:40:53 -070085 */
Pierre Peiffer01b8b072008-02-08 04:18:57 -080086static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
Kirill Korotaev4e982312006-10-02 02:18:22 -070087{
Pierre Peiffer01b8b072008-02-08 04:18:57 -080088 struct shmid_kernel *shp;
89 shp = container_of(ipcp, struct shmid_kernel, shm_perm);
90
Kirill Korotaev4e982312006-10-02 02:18:22 -070091 if (shp->shm_nattch){
92 shp->shm_perm.mode |= SHM_DEST;
93 /* Do not find it any more */
94 shp->shm_perm.key = IPC_PRIVATE;
95 shm_unlock(shp);
96 } else
97 shm_destroy(ns, shp);
98}
99
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800100#ifdef CONFIG_IPC_NS
Kirill Korotaev4e982312006-10-02 02:18:22 -0700101void shm_exit_ns(struct ipc_namespace *ns)
102{
Pierre Peiffer01b8b072008-02-08 04:18:57 -0800103 free_ipcs(ns, &shm_ids(ns), do_shm_rmid);
Serge E. Hallyn7d6feeb2009-12-15 16:47:27 -0800104 idr_destroy(&ns->ids[IPC_SHM_IDS].ipcs_idr);
Kirill Korotaev4e982312006-10-02 02:18:22 -0700105}
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800106#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107
Linus Torvalds140d0b22011-08-04 19:35:59 -1000108static int __init ipc_ns_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109{
Pierre Peiffered2ddbf2008-02-08 04:18:57 -0800110 shm_init_ns(&init_ipc_ns);
Linus Torvalds140d0b22011-08-04 19:35:59 -1000111 return 0;
112}
113
114pure_initcall(ipc_ns_init);
115
116void __init shm_init (void)
117{
Mike Waychison19b49462005-09-06 15:17:10 -0700118 ipc_init_proc_interface("sysvipc/shm",
Helge Dellerb7952182010-10-27 15:34:16 -0700119#if BITS_PER_LONG <= 32
120 " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n",
121#else
122 " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n",
123#endif
Kirill Korotaev4e982312006-10-02 02:18:22 -0700124 IPC_SHM_IDS, sysvipc_shm_proc_show);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125}
126
Nadia Derbey3e148c72007-10-18 23:40:54 -0700127/*
Nadia Derbey3e148c72007-10-18 23:40:54 -0700128 * shm_lock_(check_) routines are called in the paths where the rw_mutex
Nadia Derbey00c2bf82008-07-25 01:48:03 -0700129 * is not necessarily held.
Nadia Derbey3e148c72007-10-18 23:40:54 -0700130 */
Nadia Derbey023a5352007-10-18 23:40:51 -0700131static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132{
Nadia Derbey03f02c72007-10-18 23:40:51 -0700133 struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id);
134
Pierre Peifferb1ed88b2008-02-06 01:36:23 -0800135 if (IS_ERR(ipcp))
136 return (struct shmid_kernel *)ipcp;
137
Nadia Derbey03f02c72007-10-18 23:40:51 -0700138 return container_of(ipcp, struct shmid_kernel, shm_perm);
Nadia Derbey023a5352007-10-18 23:40:51 -0700139}
140
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400141static inline void shm_lock_by_ptr(struct shmid_kernel *ipcp)
142{
143 rcu_read_lock();
144 spin_lock(&ipcp->shm_perm.lock);
145}
146
Nadia Derbey023a5352007-10-18 23:40:51 -0700147static inline struct shmid_kernel *shm_lock_check(struct ipc_namespace *ns,
148 int id)
149{
Nadia Derbey03f02c72007-10-18 23:40:51 -0700150 struct kern_ipc_perm *ipcp = ipc_lock_check(&shm_ids(ns), id);
151
Pierre Peifferb1ed88b2008-02-06 01:36:23 -0800152 if (IS_ERR(ipcp))
153 return (struct shmid_kernel *)ipcp;
154
Nadia Derbey03f02c72007-10-18 23:40:51 -0700155 return container_of(ipcp, struct shmid_kernel, shm_perm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156}
157
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700158static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159{
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700160 ipc_rmid(&shm_ids(ns), &s->shm_perm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161}
162
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800164/* This is called by fork, once for every shm attach. */
165static void shm_open(struct vm_area_struct *vma)
Kirill Korotaev4e982312006-10-02 02:18:22 -0700166{
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800167 struct file *file = vma->vm_file;
168 struct shm_file_data *sfd = shm_file_data(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 struct shmid_kernel *shp;
170
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800171 shp = shm_lock(sfd->ns, sfd->id);
Nadia Derbey023a5352007-10-18 23:40:51 -0700172 BUG_ON(IS_ERR(shp));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 shp->shm_atim = get_seconds();
Pavel Emelyanovb4888932007-10-18 23:40:14 -0700174 shp->shm_lprid = task_tgid_vnr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 shp->shm_nattch++;
176 shm_unlock(shp);
177}
178
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179/*
180 * shm_destroy - free the struct shmid_kernel
181 *
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700182 * @ns: namespace
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183 * @shp: struct to free
184 *
Nadia Derbey3e148c72007-10-18 23:40:54 -0700185 * It has to be called with shp and shm_ids.rw_mutex (writer) locked,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 * but returns with shp unlocked and freed.
187 */
Kirill Korotaev4e982312006-10-02 02:18:22 -0700188static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189{
Kirill Korotaev4e982312006-10-02 02:18:22 -0700190 ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700191 shm_rmid(ns, shp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 shm_unlock(shp);
193 if (!is_file_hugepages(shp->shm_file))
194 shmem_lock(shp->shm_file, 0, shp->mlock_user);
Hugh Dickins353d5c32009-08-24 16:30:28 +0100195 else if (shp->mlock_user)
Josef Sipek6d630792006-12-08 02:37:11 -0800196 user_shm_unlock(shp->shm_file->f_path.dentry->d_inode->i_size,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 shp->mlock_user);
198 fput (shp->shm_file);
199 security_shm_free(shp);
200 ipc_rcu_putref(shp);
201}
202
203/*
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700204 * shm_may_destroy - identifies whether shm segment should be destroyed now
205 *
206 * Returns true if and only if there are no active users of the segment and
207 * one of the following is true:
208 *
209 * 1) shmctl(id, IPC_RMID, NULL) was called for this shp
210 *
211 * 2) sysctl kernel.shm_rmid_forced is set to 1.
212 */
213static bool shm_may_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
214{
215 return (shp->shm_nattch == 0) &&
216 (ns->shm_rmid_forced ||
217 (shp->shm_perm.mode & SHM_DEST));
218}
219
220/*
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800221 * remove the attach descriptor vma.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 * free memory for segment if it is marked destroyed.
223 * The descriptor has already been removed from the current->mm->mmap list
224 * and will later be kfree()d.
225 */
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800226static void shm_close(struct vm_area_struct *vma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227{
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800228 struct file * file = vma->vm_file;
229 struct shm_file_data *sfd = shm_file_data(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 struct shmid_kernel *shp;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800231 struct ipc_namespace *ns = sfd->ns;
Kirill Korotaev4e982312006-10-02 02:18:22 -0700232
Nadia Derbey3e148c72007-10-18 23:40:54 -0700233 down_write(&shm_ids(ns).rw_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 /* remove from the list of attaches of the shm segment */
Nadia Derbey00c2bf82008-07-25 01:48:03 -0700235 shp = shm_lock(ns, sfd->id);
Nadia Derbey023a5352007-10-18 23:40:51 -0700236 BUG_ON(IS_ERR(shp));
Pavel Emelyanovb4888932007-10-18 23:40:14 -0700237 shp->shm_lprid = task_tgid_vnr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 shp->shm_dtim = get_seconds();
239 shp->shm_nattch--;
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700240 if (shm_may_destroy(ns, shp))
Kirill Korotaev4e982312006-10-02 02:18:22 -0700241 shm_destroy(ns, shp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 else
243 shm_unlock(shp);
Nadia Derbey3e148c72007-10-18 23:40:54 -0700244 up_write(&shm_ids(ns).rw_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245}
246
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400247/* Called with ns->shm_ids(ns).rw_mutex locked */
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700248static int shm_try_destroy_current(int id, void *p, void *data)
249{
250 struct ipc_namespace *ns = data;
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400251 struct kern_ipc_perm *ipcp = p;
252 struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm);
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700253
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400254 if (shp->shm_creator != current)
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700255 return 0;
256
Vasiliy Kulikov5774ed02011-07-29 03:55:31 +0400257 /*
258 * Mark it as orphaned to destroy the segment when
259 * kernel.shm_rmid_forced is changed.
260 * It is noop if the following shm_may_destroy() returns true.
261 */
262 shp->shm_creator = NULL;
263
264 /*
265 * Don't even try to destroy it. If shm_rmid_forced=0 and IPC_RMID
266 * is not set, it shouldn't be deleted here.
267 */
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400268 if (!ns->shm_rmid_forced)
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700269 return 0;
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700270
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400271 if (shm_may_destroy(ns, shp)) {
272 shm_lock_by_ptr(shp);
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700273 shm_destroy(ns, shp);
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400274 }
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700275 return 0;
276}
277
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400278/* Called with ns->shm_ids(ns).rw_mutex locked */
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700279static int shm_try_destroy_orphaned(int id, void *p, void *data)
280{
281 struct ipc_namespace *ns = data;
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400282 struct kern_ipc_perm *ipcp = p;
283 struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm);
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700284
285 /*
286 * We want to destroy segments without users and with already
287 * exit'ed originating process.
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400288 *
289 * As shp->* are changed under rw_mutex, it's safe to skip shp locking.
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700290 */
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400291 if (shp->shm_creator != NULL)
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700292 return 0;
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700293
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400294 if (shm_may_destroy(ns, shp)) {
295 shm_lock_by_ptr(shp);
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700296 shm_destroy(ns, shp);
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400297 }
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700298 return 0;
299}
300
301void shm_destroy_orphaned(struct ipc_namespace *ns)
302{
303 down_write(&shm_ids(ns).rw_mutex);
Vasiliy Kulikov33a30ed2011-08-03 22:26:55 +0400304 if (shm_ids(ns).in_use)
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400305 idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_orphaned, ns);
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700306 up_write(&shm_ids(ns).rw_mutex);
307}
308
309
310void exit_shm(struct task_struct *task)
311{
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400312 struct ipc_namespace *ns = task->nsproxy->ipc_ns;
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700313
Vasiliy Kulikov298507d2011-08-03 22:28:26 +0400314 if (shm_ids(ns).in_use == 0)
315 return;
316
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700317 /* Destroy all already created segments, but not mapped yet */
318 down_write(&shm_ids(ns).rw_mutex);
Vasiliy Kulikov33a30ed2011-08-03 22:26:55 +0400319 if (shm_ids(ns).in_use)
Vasiliy Kulikov4c677e22011-07-29 03:56:40 +0400320 idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_current, ns);
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -0700321 up_write(&shm_ids(ns).rw_mutex);
322}
323
Nick Piggind0217ac2007-07-19 01:47:03 -0700324static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800325{
326 struct file *file = vma->vm_file;
327 struct shm_file_data *sfd = shm_file_data(file);
328
Nick Piggind0217ac2007-07-19 01:47:03 -0700329 return sfd->vm_ops->fault(vma, vmf);
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800330}
331
332#ifdef CONFIG_NUMA
Adrian Bunkd823e3e2007-10-16 23:26:42 -0700333static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800334{
335 struct file *file = vma->vm_file;
336 struct shm_file_data *sfd = shm_file_data(file);
337 int err = 0;
338 if (sfd->vm_ops->set_policy)
339 err = sfd->vm_ops->set_policy(vma, new);
340 return err;
341}
342
Adrian Bunkd823e3e2007-10-16 23:26:42 -0700343static struct mempolicy *shm_get_policy(struct vm_area_struct *vma,
344 unsigned long addr)
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800345{
346 struct file *file = vma->vm_file;
347 struct shm_file_data *sfd = shm_file_data(file);
348 struct mempolicy *pol = NULL;
349
350 if (sfd->vm_ops->get_policy)
351 pol = sfd->vm_ops->get_policy(vma, addr);
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -0700352 else if (vma->vm_policy)
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800353 pol = vma->vm_policy;
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -0700354
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800355 return pol;
356}
357#endif
358
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359static int shm_mmap(struct file * file, struct vm_area_struct * vma)
360{
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800361 struct shm_file_data *sfd = shm_file_data(file);
David Howellsb0e15192006-01-06 00:11:42 -0800362 int ret;
363
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800364 ret = sfd->file->f_op->mmap(sfd->file, vma);
365 if (ret != 0)
366 return ret;
367 sfd->vm_ops = vma->vm_ops;
David Howells2e92a3b2007-07-31 00:37:24 -0700368#ifdef CONFIG_MMU
Nick Piggin54cb8822007-07-19 01:46:59 -0700369 BUG_ON(!sfd->vm_ops->fault);
David Howells2e92a3b2007-07-31 00:37:24 -0700370#endif
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800371 vma->vm_ops = &shm_vm_ops;
372 shm_open(vma);
David Howellsb0e15192006-01-06 00:11:42 -0800373
374 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375}
376
Kirill Korotaev4e982312006-10-02 02:18:22 -0700377static int shm_release(struct inode *ino, struct file *file)
378{
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800379 struct shm_file_data *sfd = shm_file_data(file);
Kirill Korotaev4e982312006-10-02 02:18:22 -0700380
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800381 put_ipc_ns(sfd->ns);
382 shm_file_data(file) = NULL;
383 kfree(sfd);
Kirill Korotaev4e982312006-10-02 02:18:22 -0700384 return 0;
385}
386
Josef Bacik02c24a82011-07-16 20:44:56 -0400387static int shm_fsync(struct file *file, loff_t start, loff_t end, int datasync)
Adam Litke516dffd2007-03-01 15:46:08 -0800388{
Adam Litke516dffd2007-03-01 15:46:08 -0800389 struct shm_file_data *sfd = shm_file_data(file);
Adam Litke516dffd2007-03-01 15:46:08 -0800390
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200391 if (!sfd->file->f_op->fsync)
392 return -EINVAL;
Josef Bacik02c24a82011-07-16 20:44:56 -0400393 return sfd->file->f_op->fsync(sfd->file, start, end, datasync);
Adam Litke516dffd2007-03-01 15:46:08 -0800394}
395
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800396static unsigned long shm_get_unmapped_area(struct file *file,
397 unsigned long addr, unsigned long len, unsigned long pgoff,
398 unsigned long flags)
399{
400 struct shm_file_data *sfd = shm_file_data(file);
Al Viroc4caa772009-11-30 08:38:43 -0500401 return sfd->file->f_op->get_unmapped_area(sfd->file, addr, len,
402 pgoff, flags);
Adam Litke516dffd2007-03-01 15:46:08 -0800403}
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800404
Arjan van de Ven9a321442007-02-12 00:55:35 -0800405static const struct file_operations shm_file_operations = {
Kirill Korotaev4e982312006-10-02 02:18:22 -0700406 .mmap = shm_mmap,
Adam Litke516dffd2007-03-01 15:46:08 -0800407 .fsync = shm_fsync,
Kirill Korotaev4e982312006-10-02 02:18:22 -0700408 .release = shm_release,
David Howellsed5e5892010-01-15 17:01:32 -0800409#ifndef CONFIG_MMU
410 .get_unmapped_area = shm_get_unmapped_area,
411#endif
Arnd Bergmann6038f372010-08-15 18:52:59 +0200412 .llseek = noop_llseek,
Al Viroc4caa772009-11-30 08:38:43 -0500413};
414
415static const struct file_operations shm_file_operations_huge = {
416 .mmap = shm_mmap,
417 .fsync = shm_fsync,
418 .release = shm_release,
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800419 .get_unmapped_area = shm_get_unmapped_area,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200420 .llseek = noop_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421};
422
Al Viroc4caa772009-11-30 08:38:43 -0500423int is_file_shm_hugepages(struct file *file)
424{
425 return file->f_op == &shm_file_operations_huge;
426}
427
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +0400428static const struct vm_operations_struct shm_vm_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 .open = shm_open, /* callback for a new vm-area open */
430 .close = shm_close, /* callback for when the vm-area is released */
Nick Piggin54cb8822007-07-19 01:46:59 -0700431 .fault = shm_fault,
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800432#if defined(CONFIG_NUMA)
433 .set_policy = shm_set_policy,
434 .get_policy = shm_get_policy,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435#endif
436};
437
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700438/**
439 * newseg - Create a new shared memory segment
440 * @ns: namespace
441 * @params: ptr to the structure that contains key, size and shmflg
442 *
Nadia Derbey3e148c72007-10-18 23:40:54 -0700443 * Called with shm_ids.rw_mutex held as a writer.
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700444 */
445
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700446static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447{
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700448 key_t key = params->key;
449 int shmflg = params->flg;
450 size_t size = params->u.size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451 int error;
452 struct shmid_kernel *shp;
453 int numpages = (size + PAGE_SIZE -1) >> PAGE_SHIFT;
454 struct file * file;
455 char name[13];
456 int id;
KOSAKI Motohiroca16d142011-05-26 19:16:19 +0900457 vm_flags_t acctflag = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458
Kirill Korotaev4e982312006-10-02 02:18:22 -0700459 if (size < SHMMIN || size > ns->shm_ctlmax)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 return -EINVAL;
461
Guy Streeterf66d45e2007-01-23 12:20:04 -0600462 if (ns->shm_tot + numpages > ns->shm_ctlall)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 return -ENOSPC;
464
465 shp = ipc_rcu_alloc(sizeof(*shp));
466 if (!shp)
467 return -ENOMEM;
468
469 shp->shm_perm.key = key;
Andrew Mortonb33291c2006-01-08 01:02:21 -0800470 shp->shm_perm.mode = (shmflg & S_IRWXUGO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 shp->mlock_user = NULL;
472
473 shp->shm_perm.security = NULL;
474 error = security_shm_alloc(shp);
475 if (error) {
476 ipc_rcu_putref(shp);
477 return error;
478 }
479
Eric W. Biederman9d665862007-06-16 10:16:16 -0700480 sprintf (name, "SYSV%08x", key);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 if (shmflg & SHM_HUGETLB) {
Mel Gorman5a6fe122009-02-10 14:02:27 +0000482 /* hugetlb_file_setup applies strict accounting */
483 if (shmflg & SHM_NORESERVE)
484 acctflag = VM_NORESERVE;
Steven Truelove40716e22012-03-21 16:34:14 -0700485 file = hugetlb_file_setup(name, 0, size, acctflag,
Eric B Munson6bfde052009-09-21 17:03:43 -0700486 &shp->mlock_user, HUGETLB_SHMFS_INODE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 } else {
Badari Pulavartybf8f9722005-11-07 00:59:27 -0800488 /*
489 * Do not allow no accounting for OVERCOMMIT_NEVER, even
490 * if it's asked for.
491 */
492 if ((shmflg & SHM_NORESERVE) &&
493 sysctl_overcommit_memory != OVERCOMMIT_NEVER)
Linus Torvaldsfc8744a2009-01-31 15:08:56 -0800494 acctflag = VM_NORESERVE;
Badari Pulavartybf8f9722005-11-07 00:59:27 -0800495 file = shmem_file_setup(name, size, acctflag);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 }
497 error = PTR_ERR(file);
498 if (IS_ERR(file))
499 goto no_file;
500
Pierre Peiffer48dea402008-04-29 01:00:35 -0700501 id = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni);
Pierre Peiffer283bb7f2007-10-18 23:40:57 -0700502 if (id < 0) {
503 error = id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 goto no_id;
Pierre Peiffer283bb7f2007-10-18 23:40:57 -0700505 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506
Pavel Emelyanovb4888932007-10-18 23:40:14 -0700507 shp->shm_cprid = task_tgid_vnr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 shp->shm_lprid = 0;
509 shp->shm_atim = shp->shm_dtim = 0;
510 shp->shm_ctim = get_seconds();
511 shp->shm_segsz = size;
512 shp->shm_nattch = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 shp->shm_file = file;
Vasiliy Kulikov5774ed02011-07-29 03:55:31 +0400514 shp->shm_creator = current;
Badari Pulavarty30475cc2007-06-16 10:15:59 -0700515 /*
516 * shmid gets reported as "inode#" in /proc/pid/maps.
517 * proc-ps tools use this. Changing this will break them.
518 */
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700519 file->f_dentry->d_inode->i_ino = shp->shm_perm.id;
Krishnakumar R551110a2005-10-29 18:16:45 -0700520
Kirill Korotaev4e982312006-10-02 02:18:22 -0700521 ns->shm_tot += numpages;
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700522 error = shp->shm_perm.id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 shm_unlock(shp);
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700524 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525
526no_id:
Hugh Dickins2195d282009-09-12 12:21:27 +0100527 if (is_file_hugepages(file) && shp->mlock_user)
Hugh Dickins353d5c32009-08-24 16:30:28 +0100528 user_shm_unlock(size, shp->mlock_user);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529 fput(file);
530no_file:
531 security_shm_free(shp);
532 ipc_rcu_putref(shp);
533 return error;
534}
535
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700536/*
Nadia Derbey3e148c72007-10-18 23:40:54 -0700537 * Called with shm_ids.rw_mutex and ipcp locked.
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700538 */
Nadia Derbey03f02c72007-10-18 23:40:51 -0700539static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700540{
Nadia Derbey03f02c72007-10-18 23:40:51 -0700541 struct shmid_kernel *shp;
542
543 shp = container_of(ipcp, struct shmid_kernel, shm_perm);
544 return security_shm_associate(shp, shmflg);
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700545}
546
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700547/*
Nadia Derbey3e148c72007-10-18 23:40:54 -0700548 * Called with shm_ids.rw_mutex and ipcp locked.
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700549 */
Nadia Derbey03f02c72007-10-18 23:40:51 -0700550static inline int shm_more_checks(struct kern_ipc_perm *ipcp,
551 struct ipc_params *params)
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700552{
Nadia Derbey03f02c72007-10-18 23:40:51 -0700553 struct shmid_kernel *shp;
554
555 shp = container_of(ipcp, struct shmid_kernel, shm_perm);
556 if (shp->shm_segsz < params->u.size)
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700557 return -EINVAL;
558
559 return 0;
560}
561
Heiko Carstensd5460c92009-01-14 14:14:27 +0100562SYSCALL_DEFINE3(shmget, key_t, key, size_t, size, int, shmflg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563{
Kirill Korotaev4e982312006-10-02 02:18:22 -0700564 struct ipc_namespace *ns;
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700565 struct ipc_ops shm_ops;
566 struct ipc_params shm_params;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567
Kirill Korotaev4e982312006-10-02 02:18:22 -0700568 ns = current->nsproxy->ipc_ns;
569
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700570 shm_ops.getnew = newseg;
571 shm_ops.associate = shm_security;
572 shm_ops.more_checks = shm_more_checks;
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700573
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700574 shm_params.key = key;
575 shm_params.flg = shmflg;
576 shm_params.u.size = size;
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700577
Nadia Derbey7748dbf2007-10-18 23:40:49 -0700578 return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579}
580
581static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version)
582{
583 switch(version) {
584 case IPC_64:
585 return copy_to_user(buf, in, sizeof(*in));
586 case IPC_OLD:
587 {
588 struct shmid_ds out;
589
Vasiliy Kulikov3af54c92010-10-30 18:22:49 +0400590 memset(&out, 0, sizeof(out));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm);
592 out.shm_segsz = in->shm_segsz;
593 out.shm_atime = in->shm_atime;
594 out.shm_dtime = in->shm_dtime;
595 out.shm_ctime = in->shm_ctime;
596 out.shm_cpid = in->shm_cpid;
597 out.shm_lpid = in->shm_lpid;
598 out.shm_nattch = in->shm_nattch;
599
600 return copy_to_user(buf, &out, sizeof(out));
601 }
602 default:
603 return -EINVAL;
604 }
605}
606
Pierre Peiffer016d7132008-04-29 01:00:50 -0700607static inline unsigned long
608copy_shmid_from_user(struct shmid64_ds *out, void __user *buf, int version)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609{
610 switch(version) {
611 case IPC_64:
Pierre Peiffer016d7132008-04-29 01:00:50 -0700612 if (copy_from_user(out, buf, sizeof(*out)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 case IPC_OLD:
616 {
617 struct shmid_ds tbuf_old;
618
619 if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
620 return -EFAULT;
621
Pierre Peiffer016d7132008-04-29 01:00:50 -0700622 out->shm_perm.uid = tbuf_old.shm_perm.uid;
623 out->shm_perm.gid = tbuf_old.shm_perm.gid;
624 out->shm_perm.mode = tbuf_old.shm_perm.mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625
626 return 0;
627 }
628 default:
629 return -EINVAL;
630 }
631}
632
633static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminfo64 *in, int version)
634{
635 switch(version) {
636 case IPC_64:
637 return copy_to_user(buf, in, sizeof(*in));
638 case IPC_OLD:
639 {
640 struct shminfo out;
641
642 if(in->shmmax > INT_MAX)
643 out.shmmax = INT_MAX;
644 else
645 out.shmmax = (int)in->shmmax;
646
647 out.shmmin = in->shmmin;
648 out.shmmni = in->shmmni;
649 out.shmseg = in->shmseg;
650 out.shmall = in->shmall;
651
652 return copy_to_user(buf, &out, sizeof(out));
653 }
654 default:
655 return -EINVAL;
656 }
657}
658
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700659/*
Helge Dellerb7952182010-10-27 15:34:16 -0700660 * Calculate and add used RSS and swap pages of a shm.
661 * Called with shm_ids.rw_mutex held as a reader
662 */
663static void shm_add_rss_swap(struct shmid_kernel *shp,
664 unsigned long *rss_add, unsigned long *swp_add)
665{
666 struct inode *inode;
667
668 inode = shp->shm_file->f_path.dentry->d_inode;
669
670 if (is_file_hugepages(shp->shm_file)) {
671 struct address_space *mapping = inode->i_mapping;
672 struct hstate *h = hstate_file(shp->shm_file);
673 *rss_add += pages_per_huge_page(h) * mapping->nrpages;
674 } else {
675#ifdef CONFIG_SHMEM
676 struct shmem_inode_info *info = SHMEM_I(inode);
677 spin_lock(&info->lock);
678 *rss_add += inode->i_mapping->nrpages;
679 *swp_add += info->swapped;
680 spin_unlock(&info->lock);
681#else
682 *rss_add += inode->i_mapping->nrpages;
683#endif
684 }
685}
686
687/*
Nadia Derbey3e148c72007-10-18 23:40:54 -0700688 * Called with shm_ids.rw_mutex held as a reader
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700689 */
Kirill Korotaev4e982312006-10-02 02:18:22 -0700690static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
691 unsigned long *swp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692{
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700693 int next_id;
694 int total, in_use;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695
696 *rss = 0;
697 *swp = 0;
698
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700699 in_use = shm_ids(ns).in_use;
700
701 for (total = 0, next_id = 0; total < in_use; next_id++) {
Tony Battersbye562aeb2009-04-02 16:58:26 -0700702 struct kern_ipc_perm *ipc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 struct shmid_kernel *shp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704
Tony Battersbye562aeb2009-04-02 16:58:26 -0700705 ipc = idr_find(&shm_ids(ns).ipcs_idr, next_id);
706 if (ipc == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707 continue;
Tony Battersbye562aeb2009-04-02 16:58:26 -0700708 shp = container_of(ipc, struct shmid_kernel, shm_perm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709
Helge Dellerb7952182010-10-27 15:34:16 -0700710 shm_add_rss_swap(shp, rss, swp);
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700711
712 total++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 }
714}
715
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700716/*
717 * This function handles some shmctl commands which require the rw_mutex
718 * to be held in write mode.
719 * NOTE: no locks must be held, the rw_mutex is taken inside this function.
720 */
721static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
722 struct shmid_ds __user *buf, int version)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723{
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700724 struct kern_ipc_perm *ipcp;
Pierre Peiffer016d7132008-04-29 01:00:50 -0700725 struct shmid64_ds shmid64;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 struct shmid_kernel *shp;
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700727 int err;
728
729 if (cmd == IPC_SET) {
Pierre Peiffer016d7132008-04-29 01:00:50 -0700730 if (copy_shmid_from_user(&shmid64, buf, version))
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700731 return -EFAULT;
732 }
733
Serge E. Hallynb0e77592011-03-23 16:43:24 -0700734 ipcp = ipcctl_pre_down(ns, &shm_ids(ns), shmid, cmd,
735 &shmid64.shm_perm, 0);
Pierre Peiffera5f75e72008-04-29 01:00:54 -0700736 if (IS_ERR(ipcp))
737 return PTR_ERR(ipcp);
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700738
Pierre Peiffera5f75e72008-04-29 01:00:54 -0700739 shp = container_of(ipcp, struct shmid_kernel, shm_perm);
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700740
741 err = security_shm_shmctl(shp, cmd);
742 if (err)
743 goto out_unlock;
744 switch (cmd) {
745 case IPC_RMID:
746 do_shm_rmid(ns, ipcp);
747 goto out_up;
748 case IPC_SET:
Pierre Peiffer8f4a3802008-04-29 01:00:51 -0700749 ipc_update_perm(&shmid64.shm_perm, ipcp);
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700750 shp->shm_ctim = get_seconds();
751 break;
752 default:
753 err = -EINVAL;
754 }
755out_unlock:
756 shm_unlock(shp);
757out_up:
758 up_write(&shm_ids(ns).rw_mutex);
759 return err;
760}
761
Heiko Carstensd5460c92009-01-14 14:14:27 +0100762SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700763{
764 struct shmid_kernel *shp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 int err, version;
Kirill Korotaev4e982312006-10-02 02:18:22 -0700766 struct ipc_namespace *ns;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767
768 if (cmd < 0 || shmid < 0) {
769 err = -EINVAL;
770 goto out;
771 }
772
773 version = ipc_parse_version(&cmd);
Kirill Korotaev4e982312006-10-02 02:18:22 -0700774 ns = current->nsproxy->ipc_ns;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775
776 switch (cmd) { /* replace with proc interface ? */
777 case IPC_INFO:
778 {
779 struct shminfo64 shminfo;
780
781 err = security_shm_shmctl(NULL, cmd);
782 if (err)
783 return err;
784
WANG Conge8148f72009-01-06 14:42:49 -0800785 memset(&shminfo, 0, sizeof(shminfo));
Kirill Korotaev4e982312006-10-02 02:18:22 -0700786 shminfo.shmmni = shminfo.shmseg = ns->shm_ctlmni;
787 shminfo.shmmax = ns->shm_ctlmax;
788 shminfo.shmall = ns->shm_ctlall;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789
790 shminfo.shmmin = SHMMIN;
791 if(copy_shminfo_to_user (buf, &shminfo, version))
792 return -EFAULT;
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700793
Nadia Derbey3e148c72007-10-18 23:40:54 -0700794 down_read(&shm_ids(ns).rw_mutex);
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700795 err = ipc_get_maxid(&shm_ids(ns));
Nadia Derbey3e148c72007-10-18 23:40:54 -0700796 up_read(&shm_ids(ns).rw_mutex);
Nadia Derbeyf4566f02007-10-18 23:40:53 -0700797
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 if(err<0)
799 err = 0;
800 goto out;
801 }
802 case SHM_INFO:
803 {
804 struct shm_info shm_info;
805
806 err = security_shm_shmctl(NULL, cmd);
807 if (err)
808 return err;
809
WANG Conge8148f72009-01-06 14:42:49 -0800810 memset(&shm_info, 0, sizeof(shm_info));
Nadia Derbey3e148c72007-10-18 23:40:54 -0700811 down_read(&shm_ids(ns).rw_mutex);
Kirill Korotaev4e982312006-10-02 02:18:22 -0700812 shm_info.used_ids = shm_ids(ns).in_use;
813 shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp);
814 shm_info.shm_tot = ns->shm_tot;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815 shm_info.swap_attempts = 0;
816 shm_info.swap_successes = 0;
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700817 err = ipc_get_maxid(&shm_ids(ns));
Nadia Derbey3e148c72007-10-18 23:40:54 -0700818 up_read(&shm_ids(ns).rw_mutex);
WANG Conge8148f72009-01-06 14:42:49 -0800819 if (copy_to_user(buf, &shm_info, sizeof(shm_info))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820 err = -EFAULT;
821 goto out;
822 }
823
824 err = err < 0 ? 0 : err;
825 goto out;
826 }
827 case SHM_STAT:
828 case IPC_STAT:
829 {
830 struct shmid64_ds tbuf;
831 int result;
Nadia Derbey023a5352007-10-18 23:40:51 -0700832
Nadia Derbey023a5352007-10-18 23:40:51 -0700833 if (cmd == SHM_STAT) {
834 shp = shm_lock(ns, shmid);
835 if (IS_ERR(shp)) {
836 err = PTR_ERR(shp);
837 goto out;
838 }
Nadia Derbey7ca7e562007-10-18 23:40:48 -0700839 result = shp->shm_perm.id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840 } else {
Nadia Derbey023a5352007-10-18 23:40:51 -0700841 shp = shm_lock_check(ns, shmid);
842 if (IS_ERR(shp)) {
843 err = PTR_ERR(shp);
844 goto out;
845 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 result = 0;
847 }
WANG Conge8148f72009-01-06 14:42:49 -0800848 err = -EACCES;
Serge E. Hallynb0e77592011-03-23 16:43:24 -0700849 if (ipcperms(ns, &shp->shm_perm, S_IRUGO))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850 goto out_unlock;
851 err = security_shm_shmctl(shp, cmd);
852 if (err)
853 goto out_unlock;
Nadia Derbey023a5352007-10-18 23:40:51 -0700854 memset(&tbuf, 0, sizeof(tbuf));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855 kernel_to_ipc64_perm(&shp->shm_perm, &tbuf.shm_perm);
856 tbuf.shm_segsz = shp->shm_segsz;
857 tbuf.shm_atime = shp->shm_atim;
858 tbuf.shm_dtime = shp->shm_dtim;
859 tbuf.shm_ctime = shp->shm_ctim;
860 tbuf.shm_cpid = shp->shm_cprid;
861 tbuf.shm_lpid = shp->shm_lprid;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800862 tbuf.shm_nattch = shp->shm_nattch;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863 shm_unlock(shp);
864 if(copy_shmid_to_user (buf, &tbuf, version))
865 err = -EFAULT;
866 else
867 err = result;
868 goto out;
869 }
870 case SHM_LOCK:
871 case SHM_UNLOCK:
872 {
Hugh Dickins850465792012-01-20 14:34:19 -0800873 struct file *shm_file;
Lee Schermerhorn89e004ea2008-10-18 20:26:43 -0700874
Nadia Derbey023a5352007-10-18 23:40:51 -0700875 shp = shm_lock_check(ns, shmid);
876 if (IS_ERR(shp)) {
877 err = PTR_ERR(shp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700878 goto out;
879 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880
Al Viroa33e6752008-12-10 03:40:06 -0500881 audit_ipc_obj(&(shp->shm_perm));
Steve Grubb073115d2006-04-02 17:07:33 -0400882
Serge E. Hallynb0e77592011-03-23 16:43:24 -0700883 if (!ns_capable(ns->user_ns, CAP_IPC_LOCK)) {
David Howells414c0702008-11-14 10:39:06 +1100884 uid_t euid = current_euid();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885 err = -EPERM;
David Howells414c0702008-11-14 10:39:06 +1100886 if (euid != shp->shm_perm.uid &&
887 euid != shp->shm_perm.cuid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888 goto out_unlock;
Jiri Slabyf1eb1332010-03-10 15:23:05 -0800889 if (cmd == SHM_LOCK && !rlimit(RLIMIT_MEMLOCK))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890 goto out_unlock;
891 }
892
893 err = security_shm_shmctl(shp, cmd);
894 if (err)
895 goto out_unlock;
Hugh Dickins850465792012-01-20 14:34:19 -0800896
897 shm_file = shp->shm_file;
898 if (is_file_hugepages(shm_file))
899 goto out_unlock;
900
901 if (cmd == SHM_LOCK) {
David Howells86a264a2008-11-14 10:39:18 +1100902 struct user_struct *user = current_user();
Hugh Dickins850465792012-01-20 14:34:19 -0800903 err = shmem_lock(shm_file, 1, user);
904 if (!err && !(shp->shm_perm.mode & SHM_LOCKED)) {
905 shp->shm_perm.mode |= SHM_LOCKED;
906 shp->mlock_user = user;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907 }
Hugh Dickins850465792012-01-20 14:34:19 -0800908 goto out_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909 }
Hugh Dickins850465792012-01-20 14:34:19 -0800910
911 /* SHM_UNLOCK */
912 if (!(shp->shm_perm.mode & SHM_LOCKED))
913 goto out_unlock;
914 shmem_lock(shm_file, 0, shp->mlock_user);
915 shp->shm_perm.mode &= ~SHM_LOCKED;
916 shp->mlock_user = NULL;
917 get_file(shm_file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 shm_unlock(shp);
Hugh Dickins24513262012-01-20 14:34:21 -0800919 shmem_unlock_mapping(shm_file->f_mapping);
Hugh Dickins850465792012-01-20 14:34:19 -0800920 fput(shm_file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 goto out;
922 }
923 case IPC_RMID:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924 case IPC_SET:
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700925 err = shmctl_down(ns, shmid, cmd, buf, version);
926 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927 default:
Pierre Peiffer8d4cc8b2008-04-29 01:00:47 -0700928 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929 }
930
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931out_unlock:
932 shm_unlock(shp);
933out:
934 return err;
935}
936
937/*
938 * Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists.
939 *
940 * NOTE! Despite the name, this is NOT a direct system call entrypoint. The
941 * "raddr" thing points to kernel space, and there has to be a wrapper around
942 * this.
943 */
944long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
945{
946 struct shmid_kernel *shp;
947 unsigned long addr;
948 unsigned long size;
949 struct file * file;
950 int err;
951 unsigned long flags;
952 unsigned long prot;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953 int acc_mode;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800954 unsigned long user_addr;
Kirill Korotaev4e982312006-10-02 02:18:22 -0700955 struct ipc_namespace *ns;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800956 struct shm_file_data *sfd;
957 struct path path;
Al Viroaeb5d722008-09-02 15:28:45 -0400958 fmode_t f_mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700959
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800960 err = -EINVAL;
961 if (shmid < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962 goto out;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800963 else if ((addr = (ulong)shmaddr)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964 if (addr & (SHMLBA-1)) {
965 if (shmflg & SHM_RND)
966 addr &= ~(SHMLBA-1); /* round down */
967 else
968#ifndef __ARCH_FORCE_SHMLBA
969 if (addr & ~PAGE_MASK)
970#endif
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800971 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972 }
973 flags = MAP_SHARED | MAP_FIXED;
974 } else {
975 if ((shmflg & SHM_REMAP))
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800976 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977
978 flags = MAP_SHARED;
979 }
980
981 if (shmflg & SHM_RDONLY) {
982 prot = PROT_READ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983 acc_mode = S_IRUGO;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800984 f_mode = FMODE_READ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985 } else {
986 prot = PROT_READ | PROT_WRITE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987 acc_mode = S_IRUGO | S_IWUGO;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -0800988 f_mode = FMODE_READ | FMODE_WRITE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989 }
990 if (shmflg & SHM_EXEC) {
991 prot |= PROT_EXEC;
992 acc_mode |= S_IXUGO;
993 }
994
995 /*
996 * We cannot rely on the fs check since SYSV IPC does have an
997 * additional creator id...
998 */
Kirill Korotaev4e982312006-10-02 02:18:22 -0700999 ns = current->nsproxy->ipc_ns;
Nadia Derbey023a5352007-10-18 23:40:51 -07001000 shp = shm_lock_check(ns, shmid);
1001 if (IS_ERR(shp)) {
1002 err = PTR_ERR(shp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003 goto out;
Nadia Derbey023a5352007-10-18 23:40:51 -07001004 }
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001005
1006 err = -EACCES;
Serge E. Hallynb0e77592011-03-23 16:43:24 -07001007 if (ipcperms(ns, &shp->shm_perm, acc_mode))
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001008 goto out_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009
1010 err = security_shm_shmat(shp, shmaddr, shmflg);
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001011 if (err)
1012 goto out_unlock;
1013
Al Viro2c48b9c2009-08-09 00:52:35 +04001014 path = shp->shm_file->f_path;
1015 path_get(&path);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 shp->shm_nattch++;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001017 size = i_size_read(path.dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018 shm_unlock(shp);
1019
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001020 err = -ENOMEM;
1021 sfd = kzalloc(sizeof(*sfd), GFP_KERNEL);
1022 if (!sfd)
Dave Hansence8d2cd2007-10-16 23:31:13 -07001023 goto out_put_dentry;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001024
Al Viro2c48b9c2009-08-09 00:52:35 +04001025 file = alloc_file(&path, f_mode,
1026 is_file_hugepages(shp->shm_file) ?
Al Viroc4caa772009-11-30 08:38:43 -05001027 &shm_file_operations_huge :
1028 &shm_file_operations);
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001029 if (!file)
1030 goto out_free;
1031
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001032 file->private_data = sfd;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001033 file->f_mapping = shp->shm_file->f_mapping;
Nadia Derbey7ca7e562007-10-18 23:40:48 -07001034 sfd->id = shp->shm_perm.id;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001035 sfd->ns = get_ipc_ns(ns);
1036 sfd->file = shp->shm_file;
1037 sfd->vm_ops = NULL;
1038
Al Viro8b3ec682012-05-30 17:11:23 -04001039 err = security_mmap_file(file, prot, flags);
1040 if (err)
1041 goto out_fput;
1042
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043 down_write(&current->mm->mmap_sem);
1044 if (addr && !(shmflg & SHM_REMAP)) {
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001045 err = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046 if (find_vma_intersection(current->mm, addr, addr + size))
1047 goto invalid;
1048 /*
1049 * If shm segment goes below stack, make sure there is some
1050 * space left for the stack to grow (at least 4 pages).
1051 */
1052 if (addr < current->mm->start_stack &&
1053 addr > current->mm->start_stack - size - PAGE_SIZE * 5)
1054 goto invalid;
1055 }
1056
Al Viroe3fc6292012-05-30 20:08:42 -04001057 user_addr = do_mmap_pgoff(file, addr, size, prot, flags, 0);
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001058 *raddr = user_addr;
1059 err = 0;
1060 if (IS_ERR_VALUE(user_addr))
1061 err = (long)user_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001062invalid:
1063 up_write(&current->mm->mmap_sem);
1064
Al Viro8b3ec682012-05-30 17:11:23 -04001065out_fput:
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001066 fput(file);
1067
1068out_nattch:
Nadia Derbey3e148c72007-10-18 23:40:54 -07001069 down_write(&shm_ids(ns).rw_mutex);
Nadia Derbey00c2bf82008-07-25 01:48:03 -07001070 shp = shm_lock(ns, shmid);
Nadia Derbey023a5352007-10-18 23:40:51 -07001071 BUG_ON(IS_ERR(shp));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072 shp->shm_nattch--;
Vasiliy Kulikovb34a6b12011-07-26 16:08:48 -07001073 if (shm_may_destroy(ns, shp))
Kirill Korotaev4e982312006-10-02 02:18:22 -07001074 shm_destroy(ns, shp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075 else
1076 shm_unlock(shp);
Nadia Derbey3e148c72007-10-18 23:40:54 -07001077 up_write(&shm_ids(ns).rw_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078
Linus Torvalds1da177e2005-04-16 15:20:36 -07001079out:
1080 return err;
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001081
1082out_unlock:
1083 shm_unlock(shp);
1084 goto out;
1085
1086out_free:
1087 kfree(sfd);
Dave Hansence8d2cd2007-10-16 23:31:13 -07001088out_put_dentry:
Al Viro2c48b9c2009-08-09 00:52:35 +04001089 path_put(&path);
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001090 goto out_nattch;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091}
1092
Heiko Carstensd5460c92009-01-14 14:14:27 +01001093SYSCALL_DEFINE3(shmat, int, shmid, char __user *, shmaddr, int, shmflg)
Stephen Rothwell7d87e14c2005-05-01 08:59:12 -07001094{
1095 unsigned long ret;
1096 long err;
1097
1098 err = do_shmat(shmid, shmaddr, shmflg, &ret);
1099 if (err)
1100 return err;
1101 force_successful_syscall_return();
1102 return (long)ret;
1103}
1104
Linus Torvalds1da177e2005-04-16 15:20:36 -07001105/*
1106 * detach and kill segment if marked destroyed.
1107 * The work is done in shm_close.
1108 */
Heiko Carstensd5460c92009-01-14 14:14:27 +01001109SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110{
1111 struct mm_struct *mm = current->mm;
Mike Frysinger586c7e62009-06-09 16:26:23 -07001112 struct vm_area_struct *vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113 unsigned long addr = (unsigned long)shmaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001114 int retval = -EINVAL;
Mike Frysinger586c7e62009-06-09 16:26:23 -07001115#ifdef CONFIG_MMU
1116 loff_t size = 0;
1117 struct vm_area_struct *next;
1118#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119
Hugh Dickinsdf1e2fb2006-03-24 03:18:06 -08001120 if (addr & ~PAGE_MASK)
1121 return retval;
1122
Linus Torvalds1da177e2005-04-16 15:20:36 -07001123 down_write(&mm->mmap_sem);
1124
1125 /*
1126 * This function tries to be smart and unmap shm segments that
1127 * were modified by partial mlock or munmap calls:
1128 * - It first determines the size of the shm segment that should be
1129 * unmapped: It searches for a vma that is backed by shm and that
1130 * started at address shmaddr. It records it's size and then unmaps
1131 * it.
1132 * - Then it unmaps all shm vmas that started at shmaddr and that
1133 * are within the initially determined size.
1134 * Errors from do_munmap are ignored: the function only fails if
1135 * it's called with invalid parameters or if it's called to unmap
1136 * a part of a vma. Both calls in this function are for full vmas,
1137 * the parameters are directly copied from the vma itself and always
1138 * valid - therefore do_munmap cannot fail. (famous last words?)
1139 */
1140 /*
1141 * If it had been mremap()'d, the starting address would not
1142 * match the usual checks anyway. So assume all vma's are
1143 * above the starting address given.
1144 */
1145 vma = find_vma(mm, addr);
1146
David Howells8feae132009-01-08 12:04:47 +00001147#ifdef CONFIG_MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148 while (vma) {
1149 next = vma->vm_next;
1150
1151 /*
1152 * Check if the starting address would match, i.e. it's
1153 * a fragment created by mprotect() and/or munmap(), or it
1154 * otherwise it starts at this address with no hassles.
1155 */
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001156 if ((vma->vm_ops == &shm_vm_ops) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07001157 (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) {
1158
1159
Josef Sipek6d630792006-12-08 02:37:11 -08001160 size = vma->vm_file->f_path.dentry->d_inode->i_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001161 do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
1162 /*
1163 * We discovered the size of the shm segment, so
1164 * break out of here and fall through to the next
1165 * loop that uses the size information to stop
1166 * searching for matching vma's.
1167 */
1168 retval = 0;
1169 vma = next;
1170 break;
1171 }
1172 vma = next;
1173 }
1174
1175 /*
1176 * We need look no further than the maximum address a fragment
1177 * could possibly have landed at. Also cast things to loff_t to
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001178 * prevent overflows and make comparisons vs. equal-width types.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001179 */
KAMEZAWA Hiroyuki8e367092006-02-10 01:51:12 -08001180 size = PAGE_ALIGN(size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001181 while (vma && (loff_t)(vma->vm_end - addr) <= size) {
1182 next = vma->vm_next;
1183
1184 /* finding a matching vma now does not alter retval */
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001185 if ((vma->vm_ops == &shm_vm_ops) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07001186 (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff)
1187
1188 do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
1189 vma = next;
1190 }
1191
David Howells8feae132009-01-08 12:04:47 +00001192#else /* CONFIG_MMU */
1193 /* under NOMMU conditions, the exact address to be destroyed must be
1194 * given */
1195 retval = -EINVAL;
1196 if (vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) {
1197 do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
1198 retval = 0;
1199 }
1200
1201#endif
1202
Linus Torvalds1da177e2005-04-16 15:20:36 -07001203 up_write(&mm->mmap_sem);
1204 return retval;
1205}
1206
1207#ifdef CONFIG_PROC_FS
Mike Waychison19b49462005-09-06 15:17:10 -07001208static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001209{
Mike Waychison19b49462005-09-06 15:17:10 -07001210 struct shmid_kernel *shp = it;
Helge Dellerb7952182010-10-27 15:34:16 -07001211 unsigned long rss = 0, swp = 0;
1212
1213 shm_add_rss_swap(shp, &rss, &swp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001214
Paul Menage6c826812008-06-12 15:21:49 -07001215#if BITS_PER_LONG <= 32
1216#define SIZE_SPEC "%10lu"
1217#else
1218#define SIZE_SPEC "%21lu"
1219#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001220
Paul Menage6c826812008-06-12 15:21:49 -07001221 return seq_printf(s,
1222 "%10d %10d %4o " SIZE_SPEC " %5u %5u "
Helge Dellerb7952182010-10-27 15:34:16 -07001223 "%5lu %5u %5u %5u %5u %10lu %10lu %10lu "
1224 SIZE_SPEC " " SIZE_SPEC "\n",
Mike Waychison19b49462005-09-06 15:17:10 -07001225 shp->shm_perm.key,
Nadia Derbey7ca7e562007-10-18 23:40:48 -07001226 shp->shm_perm.id,
Andrew Mortonb33291c2006-01-08 01:02:21 -08001227 shp->shm_perm.mode,
Mike Waychison19b49462005-09-06 15:17:10 -07001228 shp->shm_segsz,
1229 shp->shm_cprid,
1230 shp->shm_lprid,
Eric W. Biedermanbc56bba2007-02-20 13:57:53 -08001231 shp->shm_nattch,
Mike Waychison19b49462005-09-06 15:17:10 -07001232 shp->shm_perm.uid,
1233 shp->shm_perm.gid,
1234 shp->shm_perm.cuid,
1235 shp->shm_perm.cgid,
1236 shp->shm_atim,
1237 shp->shm_dtim,
Helge Dellerb7952182010-10-27 15:34:16 -07001238 shp->shm_ctim,
1239 rss * PAGE_SIZE,
1240 swp * PAGE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241}
1242#endif