Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/ipc/util.c |
| 3 | * Copyright (C) 1992 Krishna Balasubramanian |
| 4 | * |
| 5 | * Sep 1997 - Call suser() last after "normal" permission checks so we |
| 6 | * get BSD style process accounting right. |
| 7 | * Occurs in several places in the IPC code. |
| 8 | * Chris Evans, <chris@ferret.lmh.ox.ac.uk> |
| 9 | * Nov 1999 - ipc helper functions, unified SMP locking |
Christian Kujau | 624dffc | 2006-01-15 02:43:54 +0100 | [diff] [blame] | 10 | * Manfred Spraul <manfred@colorfullife.com> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | * Oct 2002 - One lock per IPC id. RCU ipc_free for lock-free grow_ary(). |
| 12 | * Mingming Cao <cmm@us.ibm.com> |
Steve Grubb | 073115d | 2006-04-02 17:07:33 -0400 | [diff] [blame] | 13 | * Mar 2006 - support for audit of ipc object properties |
| 14 | * Dustin Kirkland <dustin.kirkland@us.ibm.com> |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 15 | * Jun 2006 - namespaces ssupport |
| 16 | * OpenVZ, SWsoft Inc. |
| 17 | * Pavel Emelianov <xemul@openvz.org> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | */ |
| 19 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/mm.h> |
| 21 | #include <linux/shm.h> |
| 22 | #include <linux/init.h> |
| 23 | #include <linux/msg.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | #include <linux/vmalloc.h> |
| 25 | #include <linux/slab.h> |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 26 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | #include <linux/highuid.h> |
| 28 | #include <linux/security.h> |
| 29 | #include <linux/rcupdate.h> |
| 30 | #include <linux/workqueue.h> |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 31 | #include <linux/seq_file.h> |
| 32 | #include <linux/proc_fs.h> |
Steve Grubb | 073115d | 2006-04-02 17:07:33 -0400 | [diff] [blame] | 33 | #include <linux/audit.h> |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 34 | #include <linux/nsproxy.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | |
| 36 | #include <asm/unistd.h> |
| 37 | |
| 38 | #include "util.h" |
| 39 | |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 40 | struct ipc_proc_iface { |
| 41 | const char *path; |
| 42 | const char *header; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 43 | int ids; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 44 | int (*show)(struct seq_file *, void *); |
| 45 | }; |
| 46 | |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 47 | struct ipc_namespace init_ipc_ns = { |
| 48 | .kref = { |
| 49 | .refcount = ATOMIC_INIT(2), |
| 50 | }, |
| 51 | }; |
| 52 | |
| 53 | #ifdef CONFIG_IPC_NS |
| 54 | static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns) |
| 55 | { |
| 56 | int err; |
| 57 | struct ipc_namespace *ns; |
| 58 | |
| 59 | err = -ENOMEM; |
| 60 | ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL); |
| 61 | if (ns == NULL) |
| 62 | goto err_mem; |
| 63 | |
| 64 | err = sem_init_ns(ns); |
| 65 | if (err) |
| 66 | goto err_sem; |
| 67 | err = msg_init_ns(ns); |
| 68 | if (err) |
| 69 | goto err_msg; |
| 70 | err = shm_init_ns(ns); |
| 71 | if (err) |
| 72 | goto err_shm; |
| 73 | |
| 74 | kref_init(&ns->kref); |
| 75 | return ns; |
| 76 | |
| 77 | err_shm: |
| 78 | msg_exit_ns(ns); |
| 79 | err_msg: |
| 80 | sem_exit_ns(ns); |
| 81 | err_sem: |
| 82 | kfree(ns); |
| 83 | err_mem: |
| 84 | return ERR_PTR(err); |
| 85 | } |
| 86 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 87 | struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *ns) |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 88 | { |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 89 | struct ipc_namespace *new_ns; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 90 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 91 | BUG_ON(!ns); |
| 92 | get_ipc_ns(ns); |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 93 | |
| 94 | if (!(flags & CLONE_NEWIPC)) |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 95 | return ns; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 96 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 97 | new_ns = clone_ipc_ns(ns); |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 98 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 99 | put_ipc_ns(ns); |
| 100 | return new_ns; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 101 | } |
| 102 | |
| 103 | void free_ipc_ns(struct kref *kref) |
| 104 | { |
| 105 | struct ipc_namespace *ns; |
| 106 | |
| 107 | ns = container_of(kref, struct ipc_namespace, kref); |
| 108 | sem_exit_ns(ns); |
| 109 | msg_exit_ns(ns); |
| 110 | shm_exit_ns(ns); |
| 111 | kfree(ns); |
| 112 | } |
Serge E. Hallyn | a28d193 | 2007-03-26 21:32:31 -0800 | [diff] [blame] | 113 | #else |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 114 | struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *ns) |
Serge E. Hallyn | a28d193 | 2007-03-26 21:32:31 -0800 | [diff] [blame] | 115 | { |
| 116 | if (flags & CLONE_NEWIPC) |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 117 | return ERR_PTR(-EINVAL); |
| 118 | return ns; |
Serge E. Hallyn | a28d193 | 2007-03-26 21:32:31 -0800 | [diff] [blame] | 119 | } |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 120 | #endif |
| 121 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | /** |
| 123 | * ipc_init - initialise IPC subsystem |
| 124 | * |
| 125 | * The various system5 IPC resources (semaphores, messages and shared |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 126 | * memory) are initialised |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | */ |
| 128 | |
| 129 | static int __init ipc_init(void) |
| 130 | { |
| 131 | sem_init(); |
| 132 | msg_init(); |
| 133 | shm_init(); |
| 134 | return 0; |
| 135 | } |
| 136 | __initcall(ipc_init); |
| 137 | |
| 138 | /** |
| 139 | * ipc_init_ids - initialise IPC identifiers |
| 140 | * @ids: Identifier set |
| 141 | * @size: Number of identifiers |
| 142 | * |
| 143 | * Given a size for the ipc identifier range (limited below IPCMNI) |
| 144 | * set up the sequence range to use then allocate and initialise the |
| 145 | * array itself. |
| 146 | */ |
| 147 | |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 148 | void __ipc_init ipc_init_ids(struct ipc_ids* ids, int size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | { |
| 150 | int i; |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 151 | |
| 152 | mutex_init(&ids->mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | |
| 154 | if(size > IPCMNI) |
| 155 | size = IPCMNI; |
| 156 | ids->in_use = 0; |
| 157 | ids->max_id = -1; |
| 158 | ids->seq = 0; |
| 159 | { |
| 160 | int seq_limit = INT_MAX/SEQ_MULTIPLIER; |
| 161 | if(seq_limit > USHRT_MAX) |
| 162 | ids->seq_max = USHRT_MAX; |
| 163 | else |
| 164 | ids->seq_max = seq_limit; |
| 165 | } |
| 166 | |
| 167 | ids->entries = ipc_rcu_alloc(sizeof(struct kern_ipc_perm *)*size + |
| 168 | sizeof(struct ipc_id_ary)); |
| 169 | |
| 170 | if(ids->entries == NULL) { |
| 171 | printk(KERN_ERR "ipc_init_ids() failed, ipc service disabled.\n"); |
| 172 | size = 0; |
| 173 | ids->entries = &ids->nullentry; |
| 174 | } |
| 175 | ids->entries->size = size; |
| 176 | for(i=0;i<size;i++) |
| 177 | ids->entries->p[i] = NULL; |
| 178 | } |
| 179 | |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 180 | #ifdef CONFIG_PROC_FS |
Arjan van de Ven | 9a32144 | 2007-02-12 00:55:35 -0800 | [diff] [blame] | 181 | static const struct file_operations sysvipc_proc_fops; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 182 | /** |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 183 | * ipc_init_proc_interface - Create a proc interface for sysipc types using a seq_file interface. |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 184 | * @path: Path in procfs |
| 185 | * @header: Banner to be printed at the beginning of the file. |
| 186 | * @ids: ipc id table to iterate. |
| 187 | * @show: show routine. |
| 188 | */ |
| 189 | void __init ipc_init_proc_interface(const char *path, const char *header, |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 190 | int ids, int (*show)(struct seq_file *, void *)) |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 191 | { |
| 192 | struct proc_dir_entry *pde; |
| 193 | struct ipc_proc_iface *iface; |
| 194 | |
| 195 | iface = kmalloc(sizeof(*iface), GFP_KERNEL); |
| 196 | if (!iface) |
| 197 | return; |
| 198 | iface->path = path; |
| 199 | iface->header = header; |
| 200 | iface->ids = ids; |
| 201 | iface->show = show; |
| 202 | |
| 203 | pde = create_proc_entry(path, |
| 204 | S_IRUGO, /* world readable */ |
| 205 | NULL /* parent dir */); |
| 206 | if (pde) { |
| 207 | pde->data = iface; |
| 208 | pde->proc_fops = &sysvipc_proc_fops; |
| 209 | } else { |
| 210 | kfree(iface); |
| 211 | } |
| 212 | } |
| 213 | #endif |
| 214 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | /** |
| 216 | * ipc_findkey - find a key in an ipc identifier set |
| 217 | * @ids: Identifier set |
| 218 | * @key: The key to find |
| 219 | * |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 220 | * Requires ipc_ids.mutex locked. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | * Returns the identifier if found or -1 if not. |
| 222 | */ |
| 223 | |
| 224 | int ipc_findkey(struct ipc_ids* ids, key_t key) |
| 225 | { |
| 226 | int id; |
| 227 | struct kern_ipc_perm* p; |
| 228 | int max_id = ids->max_id; |
| 229 | |
| 230 | /* |
| 231 | * rcu_dereference() is not needed here |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 232 | * since ipc_ids.mutex is held |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | */ |
| 234 | for (id = 0; id <= max_id; id++) { |
| 235 | p = ids->entries->p[id]; |
| 236 | if(p==NULL) |
| 237 | continue; |
| 238 | if (key == p->key) |
| 239 | return id; |
| 240 | } |
| 241 | return -1; |
| 242 | } |
| 243 | |
| 244 | /* |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 245 | * Requires ipc_ids.mutex locked |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | */ |
| 247 | static int grow_ary(struct ipc_ids* ids, int newsize) |
| 248 | { |
| 249 | struct ipc_id_ary* new; |
| 250 | struct ipc_id_ary* old; |
| 251 | int i; |
| 252 | int size = ids->entries->size; |
| 253 | |
| 254 | if(newsize > IPCMNI) |
| 255 | newsize = IPCMNI; |
| 256 | if(newsize <= size) |
| 257 | return newsize; |
| 258 | |
| 259 | new = ipc_rcu_alloc(sizeof(struct kern_ipc_perm *)*newsize + |
| 260 | sizeof(struct ipc_id_ary)); |
| 261 | if(new == NULL) |
| 262 | return size; |
| 263 | new->size = newsize; |
Alexey Kuznetsov | a9a5cd5 | 2006-04-17 15:39:23 +0400 | [diff] [blame] | 264 | memcpy(new->p, ids->entries->p, sizeof(struct kern_ipc_perm *)*size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | for(i=size;i<newsize;i++) { |
| 266 | new->p[i] = NULL; |
| 267 | } |
| 268 | old = ids->entries; |
| 269 | |
| 270 | /* |
| 271 | * Use rcu_assign_pointer() to make sure the memcpyed contents |
| 272 | * of the new array are visible before the new array becomes visible. |
| 273 | */ |
| 274 | rcu_assign_pointer(ids->entries, new); |
| 275 | |
Pavel Emelianov | c7e12b8 | 2006-11-02 22:07:03 -0800 | [diff] [blame] | 276 | __ipc_fini_ids(ids, old); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | return newsize; |
| 278 | } |
| 279 | |
| 280 | /** |
| 281 | * ipc_addid - add an IPC identifier |
| 282 | * @ids: IPC identifier set |
| 283 | * @new: new IPC permission set |
| 284 | * @size: new size limit for the id array |
| 285 | * |
| 286 | * Add an entry 'new' to the IPC arrays. The permissions object is |
| 287 | * initialised and the first free entry is set up and the id assigned |
| 288 | * is returned. The list is returned in a locked state on success. |
| 289 | * On failure the list is not locked and -1 is returned. |
| 290 | * |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 291 | * Called with ipc_ids.mutex held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | */ |
| 293 | |
| 294 | int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size) |
| 295 | { |
| 296 | int id; |
| 297 | |
| 298 | size = grow_ary(ids,size); |
| 299 | |
| 300 | /* |
| 301 | * rcu_dereference()() is not needed here since |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 302 | * ipc_ids.mutex is held |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | */ |
| 304 | for (id = 0; id < size; id++) { |
| 305 | if(ids->entries->p[id] == NULL) |
| 306 | goto found; |
| 307 | } |
| 308 | return -1; |
| 309 | found: |
| 310 | ids->in_use++; |
| 311 | if (id > ids->max_id) |
| 312 | ids->max_id = id; |
| 313 | |
| 314 | new->cuid = new->uid = current->euid; |
| 315 | new->gid = new->cgid = current->egid; |
| 316 | |
| 317 | new->seq = ids->seq++; |
| 318 | if(ids->seq > ids->seq_max) |
| 319 | ids->seq = 0; |
| 320 | |
| 321 | spin_lock_init(&new->lock); |
| 322 | new->deleted = 0; |
| 323 | rcu_read_lock(); |
| 324 | spin_lock(&new->lock); |
| 325 | ids->entries->p[id] = new; |
| 326 | return id; |
| 327 | } |
| 328 | |
| 329 | /** |
| 330 | * ipc_rmid - remove an IPC identifier |
| 331 | * @ids: identifier set |
| 332 | * @id: Identifier to remove |
| 333 | * |
| 334 | * The identifier must be valid, and in use. The kernel will panic if |
| 335 | * fed an invalid identifier. The entry is removed and internal |
| 336 | * variables recomputed. The object associated with the identifier |
| 337 | * is returned. |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 338 | * ipc_ids.mutex and the spinlock for this ID is hold before this function |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | * is called, and remain locked on the exit. |
| 340 | */ |
| 341 | |
| 342 | struct kern_ipc_perm* ipc_rmid(struct ipc_ids* ids, int id) |
| 343 | { |
| 344 | struct kern_ipc_perm* p; |
| 345 | int lid = id % SEQ_MULTIPLIER; |
Eric Sesterhenn | 9bc98fc | 2006-04-01 01:20:23 +0200 | [diff] [blame] | 346 | BUG_ON(lid >= ids->entries->size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | |
| 348 | /* |
| 349 | * do not need a rcu_dereference()() here to force ordering |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 350 | * on Alpha, since the ipc_ids.mutex is held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | */ |
| 352 | p = ids->entries->p[lid]; |
| 353 | ids->entries->p[lid] = NULL; |
Eric Sesterhenn | 9bc98fc | 2006-04-01 01:20:23 +0200 | [diff] [blame] | 354 | BUG_ON(p==NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | ids->in_use--; |
| 356 | |
| 357 | if (lid == ids->max_id) { |
| 358 | do { |
| 359 | lid--; |
| 360 | if(lid == -1) |
| 361 | break; |
| 362 | } while (ids->entries->p[lid] == NULL); |
| 363 | ids->max_id = lid; |
| 364 | } |
| 365 | p->deleted = 1; |
| 366 | return p; |
| 367 | } |
| 368 | |
| 369 | /** |
| 370 | * ipc_alloc - allocate ipc space |
| 371 | * @size: size desired |
| 372 | * |
| 373 | * Allocate memory from the appropriate pools and return a pointer to it. |
| 374 | * NULL is returned if the allocation fails |
| 375 | */ |
| 376 | |
| 377 | void* ipc_alloc(int size) |
| 378 | { |
| 379 | void* out; |
| 380 | if(size > PAGE_SIZE) |
| 381 | out = vmalloc(size); |
| 382 | else |
| 383 | out = kmalloc(size, GFP_KERNEL); |
| 384 | return out; |
| 385 | } |
| 386 | |
| 387 | /** |
| 388 | * ipc_free - free ipc space |
| 389 | * @ptr: pointer returned by ipc_alloc |
| 390 | * @size: size of block |
| 391 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 392 | * Free a block created with ipc_alloc(). The caller must know the size |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | * used in the allocation call. |
| 394 | */ |
| 395 | |
| 396 | void ipc_free(void* ptr, int size) |
| 397 | { |
| 398 | if(size > PAGE_SIZE) |
| 399 | vfree(ptr); |
| 400 | else |
| 401 | kfree(ptr); |
| 402 | } |
| 403 | |
| 404 | /* |
| 405 | * rcu allocations: |
| 406 | * There are three headers that are prepended to the actual allocation: |
| 407 | * - during use: ipc_rcu_hdr. |
| 408 | * - during the rcu grace period: ipc_rcu_grace. |
| 409 | * - [only if vmalloc]: ipc_rcu_sched. |
| 410 | * Their lifetime doesn't overlap, thus the headers share the same memory. |
| 411 | * Unlike a normal union, they are right-aligned, thus some container_of |
| 412 | * forward/backward casting is necessary: |
| 413 | */ |
| 414 | struct ipc_rcu_hdr |
| 415 | { |
| 416 | int refcount; |
| 417 | int is_vmalloc; |
| 418 | void *data[0]; |
| 419 | }; |
| 420 | |
| 421 | |
| 422 | struct ipc_rcu_grace |
| 423 | { |
| 424 | struct rcu_head rcu; |
| 425 | /* "void *" makes sure alignment of following data is sane. */ |
| 426 | void *data[0]; |
| 427 | }; |
| 428 | |
| 429 | struct ipc_rcu_sched |
| 430 | { |
| 431 | struct work_struct work; |
| 432 | /* "void *" makes sure alignment of following data is sane. */ |
| 433 | void *data[0]; |
| 434 | }; |
| 435 | |
| 436 | #define HDRLEN_KMALLOC (sizeof(struct ipc_rcu_grace) > sizeof(struct ipc_rcu_hdr) ? \ |
| 437 | sizeof(struct ipc_rcu_grace) : sizeof(struct ipc_rcu_hdr)) |
| 438 | #define HDRLEN_VMALLOC (sizeof(struct ipc_rcu_sched) > HDRLEN_KMALLOC ? \ |
| 439 | sizeof(struct ipc_rcu_sched) : HDRLEN_KMALLOC) |
| 440 | |
| 441 | static inline int rcu_use_vmalloc(int size) |
| 442 | { |
| 443 | /* Too big for a single page? */ |
| 444 | if (HDRLEN_KMALLOC + size > PAGE_SIZE) |
| 445 | return 1; |
| 446 | return 0; |
| 447 | } |
| 448 | |
| 449 | /** |
| 450 | * ipc_rcu_alloc - allocate ipc and rcu space |
| 451 | * @size: size desired |
| 452 | * |
| 453 | * Allocate memory for the rcu header structure + the object. |
| 454 | * Returns the pointer to the object. |
| 455 | * NULL is returned if the allocation fails. |
| 456 | */ |
| 457 | |
| 458 | void* ipc_rcu_alloc(int size) |
| 459 | { |
| 460 | void* out; |
| 461 | /* |
| 462 | * We prepend the allocation with the rcu struct, and |
| 463 | * workqueue if necessary (for vmalloc). |
| 464 | */ |
| 465 | if (rcu_use_vmalloc(size)) { |
| 466 | out = vmalloc(HDRLEN_VMALLOC + size); |
| 467 | if (out) { |
| 468 | out += HDRLEN_VMALLOC; |
| 469 | container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; |
| 470 | container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; |
| 471 | } |
| 472 | } else { |
| 473 | out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); |
| 474 | if (out) { |
| 475 | out += HDRLEN_KMALLOC; |
| 476 | container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; |
| 477 | container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; |
| 478 | } |
| 479 | } |
| 480 | |
| 481 | return out; |
| 482 | } |
| 483 | |
| 484 | void ipc_rcu_getref(void *ptr) |
| 485 | { |
| 486 | container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; |
| 487 | } |
| 488 | |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 489 | static void ipc_do_vfree(struct work_struct *work) |
| 490 | { |
| 491 | vfree(container_of(work, struct ipc_rcu_sched, work)); |
| 492 | } |
| 493 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 494 | /** |
Randy Dunlap | 1e5d533 | 2005-11-07 01:01:06 -0800 | [diff] [blame] | 495 | * ipc_schedule_free - free ipc + rcu space |
| 496 | * @head: RCU callback structure for queued work |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | * |
| 498 | * Since RCU callback function is called in bh, |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 499 | * we need to defer the vfree to schedule_work(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | */ |
| 501 | static void ipc_schedule_free(struct rcu_head *head) |
| 502 | { |
| 503 | struct ipc_rcu_grace *grace = |
| 504 | container_of(head, struct ipc_rcu_grace, rcu); |
| 505 | struct ipc_rcu_sched *sched = |
| 506 | container_of(&(grace->data[0]), struct ipc_rcu_sched, data[0]); |
| 507 | |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 508 | INIT_WORK(&sched->work, ipc_do_vfree); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | schedule_work(&sched->work); |
| 510 | } |
| 511 | |
| 512 | /** |
Randy Dunlap | 1e5d533 | 2005-11-07 01:01:06 -0800 | [diff] [blame] | 513 | * ipc_immediate_free - free ipc + rcu space |
| 514 | * @head: RCU callback structure that contains pointer to be freed |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 516 | * Free from the RCU callback context. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 517 | */ |
| 518 | static void ipc_immediate_free(struct rcu_head *head) |
| 519 | { |
| 520 | struct ipc_rcu_grace *free = |
| 521 | container_of(head, struct ipc_rcu_grace, rcu); |
| 522 | kfree(free); |
| 523 | } |
| 524 | |
| 525 | void ipc_rcu_putref(void *ptr) |
| 526 | { |
| 527 | if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) |
| 528 | return; |
| 529 | |
| 530 | if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) { |
| 531 | call_rcu(&container_of(ptr, struct ipc_rcu_grace, data)->rcu, |
| 532 | ipc_schedule_free); |
| 533 | } else { |
| 534 | call_rcu(&container_of(ptr, struct ipc_rcu_grace, data)->rcu, |
| 535 | ipc_immediate_free); |
| 536 | } |
| 537 | } |
| 538 | |
| 539 | /** |
| 540 | * ipcperms - check IPC permissions |
| 541 | * @ipcp: IPC permission set |
| 542 | * @flag: desired permission set. |
| 543 | * |
| 544 | * Check user, group, other permissions for access |
| 545 | * to ipc resources. return 0 if allowed |
| 546 | */ |
| 547 | |
| 548 | int ipcperms (struct kern_ipc_perm *ipcp, short flag) |
| 549 | { /* flag will most probably be 0 or S_...UGO from <linux/stat.h> */ |
Steve Grubb | 073115d | 2006-04-02 17:07:33 -0400 | [diff] [blame] | 550 | int requested_mode, granted_mode, err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | |
Steve Grubb | 073115d | 2006-04-02 17:07:33 -0400 | [diff] [blame] | 552 | if (unlikely((err = audit_ipc_obj(ipcp)))) |
| 553 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | requested_mode = (flag >> 6) | (flag >> 3) | flag; |
| 555 | granted_mode = ipcp->mode; |
| 556 | if (current->euid == ipcp->cuid || current->euid == ipcp->uid) |
| 557 | granted_mode >>= 6; |
| 558 | else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid)) |
| 559 | granted_mode >>= 3; |
| 560 | /* is there some bit set in requested_mode but not in granted_mode? */ |
| 561 | if ((requested_mode & ~granted_mode & 0007) && |
| 562 | !capable(CAP_IPC_OWNER)) |
| 563 | return -1; |
| 564 | |
| 565 | return security_ipc_permission(ipcp, flag); |
| 566 | } |
| 567 | |
| 568 | /* |
| 569 | * Functions to convert between the kern_ipc_perm structure and the |
| 570 | * old/new ipc_perm structures |
| 571 | */ |
| 572 | |
| 573 | /** |
| 574 | * kernel_to_ipc64_perm - convert kernel ipc permissions to user |
| 575 | * @in: kernel permissions |
| 576 | * @out: new style IPC permissions |
| 577 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 578 | * Turn the kernel object @in into a set of permissions descriptions |
| 579 | * for returning to userspace (@out). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | */ |
| 581 | |
| 582 | |
| 583 | void kernel_to_ipc64_perm (struct kern_ipc_perm *in, struct ipc64_perm *out) |
| 584 | { |
| 585 | out->key = in->key; |
| 586 | out->uid = in->uid; |
| 587 | out->gid = in->gid; |
| 588 | out->cuid = in->cuid; |
| 589 | out->cgid = in->cgid; |
| 590 | out->mode = in->mode; |
| 591 | out->seq = in->seq; |
| 592 | } |
| 593 | |
| 594 | /** |
| 595 | * ipc64_perm_to_ipc_perm - convert old ipc permissions to new |
| 596 | * @in: new style IPC permissions |
| 597 | * @out: old style IPC permissions |
| 598 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 599 | * Turn the new style permissions object @in into a compatibility |
| 600 | * object and store it into the @out pointer. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 601 | */ |
| 602 | |
| 603 | void ipc64_perm_to_ipc_perm (struct ipc64_perm *in, struct ipc_perm *out) |
| 604 | { |
| 605 | out->key = in->key; |
| 606 | SET_UID(out->uid, in->uid); |
| 607 | SET_GID(out->gid, in->gid); |
| 608 | SET_UID(out->cuid, in->cuid); |
| 609 | SET_GID(out->cgid, in->cgid); |
| 610 | out->mode = in->mode; |
| 611 | out->seq = in->seq; |
| 612 | } |
| 613 | |
| 614 | /* |
| 615 | * So far only shm_get_stat() calls ipc_get() via shm_get(), so ipc_get() |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 616 | * is called with shm_ids.mutex locked. Since grow_ary() is also called with |
| 617 | * shm_ids.mutex down(for Shared Memory), there is no need to add read |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 618 | * barriers here to gurantee the writes in grow_ary() are seen in order |
| 619 | * here (for Alpha). |
| 620 | * |
Ingo Molnar | 5f921ae | 2006-03-26 01:37:17 -0800 | [diff] [blame] | 621 | * However ipc_get() itself does not necessary require ipc_ids.mutex down. So |
| 622 | * if in the future ipc_get() is used by other places without ipc_ids.mutex |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | * down, then ipc_get() needs read memery barriers as ipc_lock() does. |
| 624 | */ |
| 625 | struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id) |
| 626 | { |
| 627 | struct kern_ipc_perm* out; |
| 628 | int lid = id % SEQ_MULTIPLIER; |
| 629 | if(lid >= ids->entries->size) |
| 630 | return NULL; |
| 631 | out = ids->entries->p[lid]; |
| 632 | return out; |
| 633 | } |
| 634 | |
| 635 | struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id) |
| 636 | { |
| 637 | struct kern_ipc_perm* out; |
| 638 | int lid = id % SEQ_MULTIPLIER; |
| 639 | struct ipc_id_ary* entries; |
| 640 | |
| 641 | rcu_read_lock(); |
| 642 | entries = rcu_dereference(ids->entries); |
| 643 | if(lid >= entries->size) { |
| 644 | rcu_read_unlock(); |
| 645 | return NULL; |
| 646 | } |
| 647 | out = entries->p[lid]; |
| 648 | if(out == NULL) { |
| 649 | rcu_read_unlock(); |
| 650 | return NULL; |
| 651 | } |
| 652 | spin_lock(&out->lock); |
| 653 | |
| 654 | /* ipc_rmid() may have already freed the ID while ipc_lock |
| 655 | * was spinning: here verify that the structure is still valid |
| 656 | */ |
| 657 | if (out->deleted) { |
| 658 | spin_unlock(&out->lock); |
| 659 | rcu_read_unlock(); |
| 660 | return NULL; |
| 661 | } |
| 662 | return out; |
| 663 | } |
| 664 | |
| 665 | void ipc_lock_by_ptr(struct kern_ipc_perm *perm) |
| 666 | { |
| 667 | rcu_read_lock(); |
| 668 | spin_lock(&perm->lock); |
| 669 | } |
| 670 | |
| 671 | void ipc_unlock(struct kern_ipc_perm* perm) |
| 672 | { |
| 673 | spin_unlock(&perm->lock); |
| 674 | rcu_read_unlock(); |
| 675 | } |
| 676 | |
| 677 | int ipc_buildid(struct ipc_ids* ids, int id, int seq) |
| 678 | { |
| 679 | return SEQ_MULTIPLIER*seq + id; |
| 680 | } |
| 681 | |
| 682 | int ipc_checkid(struct ipc_ids* ids, struct kern_ipc_perm* ipcp, int uid) |
| 683 | { |
| 684 | if(uid/SEQ_MULTIPLIER != ipcp->seq) |
| 685 | return 1; |
| 686 | return 0; |
| 687 | } |
| 688 | |
| 689 | #ifdef __ARCH_WANT_IPC_PARSE_VERSION |
| 690 | |
| 691 | |
| 692 | /** |
| 693 | * ipc_parse_version - IPC call version |
| 694 | * @cmd: pointer to command |
| 695 | * |
| 696 | * Return IPC_64 for new style IPC and IPC_OLD for old style IPC. |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 697 | * The @cmd value is turned from an encoding command and version into |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | * just the command code. |
| 699 | */ |
| 700 | |
| 701 | int ipc_parse_version (int *cmd) |
| 702 | { |
| 703 | if (*cmd & IPC_64) { |
| 704 | *cmd ^= IPC_64; |
| 705 | return IPC_64; |
| 706 | } else { |
| 707 | return IPC_OLD; |
| 708 | } |
| 709 | } |
| 710 | |
| 711 | #endif /* __ARCH_WANT_IPC_PARSE_VERSION */ |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 712 | |
| 713 | #ifdef CONFIG_PROC_FS |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 714 | struct ipc_proc_iter { |
| 715 | struct ipc_namespace *ns; |
| 716 | struct ipc_proc_iface *iface; |
| 717 | }; |
| 718 | |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 719 | static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos) |
| 720 | { |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 721 | struct ipc_proc_iter *iter = s->private; |
| 722 | struct ipc_proc_iface *iface = iter->iface; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 723 | struct kern_ipc_perm *ipc = it; |
| 724 | loff_t p; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 725 | struct ipc_ids *ids; |
| 726 | |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 727 | ids = iter->ns->ids[iface->ids]; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 728 | |
| 729 | /* If we had an ipc id locked before, unlock it */ |
| 730 | if (ipc && ipc != SEQ_START_TOKEN) |
| 731 | ipc_unlock(ipc); |
| 732 | |
| 733 | /* |
| 734 | * p = *pos - 1 (because id 0 starts at position 1) |
| 735 | * + 1 (because we increment the position by one) |
| 736 | */ |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 737 | for (p = *pos; p <= ids->max_id; p++) { |
| 738 | if ((ipc = ipc_lock(ids, p)) != NULL) { |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 739 | *pos = p + 1; |
| 740 | return ipc; |
| 741 | } |
| 742 | } |
| 743 | |
| 744 | /* Out of range - return NULL to terminate iteration */ |
| 745 | return NULL; |
| 746 | } |
| 747 | |
| 748 | /* |
| 749 | * File positions: pos 0 -> header, pos n -> ipc id + 1. |
| 750 | * SeqFile iterator: iterator value locked shp or SEQ_TOKEN_START. |
| 751 | */ |
| 752 | static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos) |
| 753 | { |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 754 | struct ipc_proc_iter *iter = s->private; |
| 755 | struct ipc_proc_iface *iface = iter->iface; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 756 | struct kern_ipc_perm *ipc; |
| 757 | loff_t p; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 758 | struct ipc_ids *ids; |
| 759 | |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 760 | ids = iter->ns->ids[iface->ids]; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 761 | |
| 762 | /* |
| 763 | * Take the lock - this will be released by the corresponding |
| 764 | * call to stop(). |
| 765 | */ |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 766 | mutex_lock(&ids->mutex); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 767 | |
| 768 | /* pos < 0 is invalid */ |
| 769 | if (*pos < 0) |
| 770 | return NULL; |
| 771 | |
| 772 | /* pos == 0 means header */ |
| 773 | if (*pos == 0) |
| 774 | return SEQ_START_TOKEN; |
| 775 | |
| 776 | /* Find the (pos-1)th ipc */ |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 777 | for (p = *pos - 1; p <= ids->max_id; p++) { |
| 778 | if ((ipc = ipc_lock(ids, p)) != NULL) { |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 779 | *pos = p + 1; |
| 780 | return ipc; |
| 781 | } |
| 782 | } |
| 783 | return NULL; |
| 784 | } |
| 785 | |
| 786 | static void sysvipc_proc_stop(struct seq_file *s, void *it) |
| 787 | { |
| 788 | struct kern_ipc_perm *ipc = it; |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 789 | struct ipc_proc_iter *iter = s->private; |
| 790 | struct ipc_proc_iface *iface = iter->iface; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 791 | struct ipc_ids *ids; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 792 | |
| 793 | /* If we had a locked segment, release it */ |
| 794 | if (ipc && ipc != SEQ_START_TOKEN) |
| 795 | ipc_unlock(ipc); |
| 796 | |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 797 | ids = iter->ns->ids[iface->ids]; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 798 | /* Release the lock we took in start() */ |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 799 | mutex_unlock(&ids->mutex); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 800 | } |
| 801 | |
| 802 | static int sysvipc_proc_show(struct seq_file *s, void *it) |
| 803 | { |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 804 | struct ipc_proc_iter *iter = s->private; |
| 805 | struct ipc_proc_iface *iface = iter->iface; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 806 | |
| 807 | if (it == SEQ_START_TOKEN) |
| 808 | return seq_puts(s, iface->header); |
| 809 | |
| 810 | return iface->show(s, it); |
| 811 | } |
| 812 | |
| 813 | static struct seq_operations sysvipc_proc_seqops = { |
| 814 | .start = sysvipc_proc_start, |
| 815 | .stop = sysvipc_proc_stop, |
| 816 | .next = sysvipc_proc_next, |
| 817 | .show = sysvipc_proc_show, |
| 818 | }; |
| 819 | |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 820 | static int sysvipc_proc_open(struct inode *inode, struct file *file) |
| 821 | { |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 822 | int ret; |
| 823 | struct seq_file *seq; |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 824 | struct ipc_proc_iter *iter; |
| 825 | |
| 826 | ret = -ENOMEM; |
| 827 | iter = kmalloc(sizeof(*iter), GFP_KERNEL); |
| 828 | if (!iter) |
| 829 | goto out; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 830 | |
| 831 | ret = seq_open(file, &sysvipc_proc_seqops); |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 832 | if (ret) |
| 833 | goto out_kfree; |
| 834 | |
| 835 | seq = file->private_data; |
| 836 | seq->private = iter; |
| 837 | |
| 838 | iter->iface = PDE(inode)->data; |
| 839 | iter->ns = get_ipc_ns(current->nsproxy->ipc_ns); |
| 840 | out: |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 841 | return ret; |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 842 | out_kfree: |
| 843 | kfree(iter); |
| 844 | goto out; |
| 845 | } |
| 846 | |
| 847 | static int sysvipc_proc_release(struct inode *inode, struct file *file) |
| 848 | { |
| 849 | struct seq_file *seq = file->private_data; |
| 850 | struct ipc_proc_iter *iter = seq->private; |
| 851 | put_ipc_ns(iter->ns); |
| 852 | return seq_release_private(inode, file); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 853 | } |
| 854 | |
Arjan van de Ven | 9a32144 | 2007-02-12 00:55:35 -0800 | [diff] [blame] | 855 | static const struct file_operations sysvipc_proc_fops = { |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 856 | .open = sysvipc_proc_open, |
| 857 | .read = seq_read, |
| 858 | .llseek = seq_lseek, |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 859 | .release = sysvipc_proc_release, |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 860 | }; |
| 861 | #endif /* CONFIG_PROC_FS */ |