sysv_shm.c revision 1.46 1 1.46 perry /* $NetBSD: sysv_shm.c,v 1.46 1998/08/04 04:03:16 perry Exp $ */
2 1.22 cgd
3 1.11 hpeyerl /*
4 1.17 mycroft * Copyright (c) 1994 Adam Glass and Charles Hannum. All rights reserved.
5 1.11 hpeyerl *
6 1.11 hpeyerl * Redistribution and use in source and binary forms, with or without
7 1.11 hpeyerl * modification, are permitted provided that the following conditions
8 1.11 hpeyerl * are met:
9 1.11 hpeyerl * 1. Redistributions of source code must retain the above copyright
10 1.11 hpeyerl * notice, this list of conditions and the following disclaimer.
11 1.17 mycroft * 2. Redistributions in binary form must reproduce the above copyright
12 1.17 mycroft * notice, this list of conditions and the following disclaimer in the
13 1.17 mycroft * documentation and/or other materials provided with the distribution.
14 1.17 mycroft * 3. All advertising materials mentioning features or use of this software
15 1.17 mycroft * must display the following acknowledgement:
16 1.17 mycroft * This product includes software developed by Adam Glass and Charles
17 1.17 mycroft * Hannum.
18 1.17 mycroft * 4. The names of the authors may not be used to endorse or promote products
19 1.11 hpeyerl * derived from this software without specific prior written permission.
20 1.11 hpeyerl *
21 1.17 mycroft * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
22 1.17 mycroft * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 1.17 mycroft * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 1.17 mycroft * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25 1.17 mycroft * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 1.17 mycroft * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 1.17 mycroft * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 1.17 mycroft * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 1.17 mycroft * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 1.17 mycroft * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 1.11 hpeyerl */
32 1.43 mrg
33 1.43 mrg #include "opt_uvm.h"
34 1.11 hpeyerl
35 1.11 hpeyerl #include <sys/types.h>
36 1.11 hpeyerl #include <sys/param.h>
37 1.11 hpeyerl #include <sys/kernel.h>
38 1.11 hpeyerl #include <sys/shm.h>
39 1.11 hpeyerl #include <sys/proc.h>
40 1.11 hpeyerl #include <sys/uio.h>
41 1.11 hpeyerl #include <sys/time.h>
42 1.11 hpeyerl #include <sys/malloc.h>
43 1.11 hpeyerl #include <sys/mman.h>
44 1.11 hpeyerl #include <sys/systm.h>
45 1.12 mycroft #include <sys/stat.h>
46 1.11 hpeyerl
47 1.26 cgd #include <sys/mount.h>
48 1.26 cgd #include <sys/syscallargs.h>
49 1.26 cgd
50 1.11 hpeyerl #include <vm/vm.h>
51 1.42 mrg #ifdef UVM
52 1.42 mrg #include <uvm/uvm_extern.h>
53 1.42 mrg #else
54 1.11 hpeyerl #include <vm/vm_map.h>
55 1.11 hpeyerl #include <vm/vm_kern.h>
56 1.42 mrg #endif
57 1.35 christos
58 1.35 christos struct shmid_ds *shm_find_segment_by_shmid __P((int));
59 1.35 christos
60 1.11 hpeyerl /*
61 1.11 hpeyerl * Provides the following externally accessible functions:
62 1.11 hpeyerl *
63 1.41 thorpej * shminit(void); initialization
64 1.41 thorpej * shmexit(struct vmspace *) cleanup
65 1.41 thorpej * shmfork(struct vmspace *, struct vmspace *) fork handling
66 1.11 hpeyerl * shmsys(arg1, arg2, arg3, arg4); shm{at,ctl,dt,get}(arg2, arg3, arg4)
67 1.11 hpeyerl *
68 1.11 hpeyerl * Structures:
69 1.11 hpeyerl * shmsegs (an array of 'struct shmid_ds')
70 1.11 hpeyerl * per proc array of 'struct shmmap_state'
71 1.11 hpeyerl */
72 1.12 mycroft
73 1.16 mycroft #define SHMSEG_FREE 0x0200
74 1.16 mycroft #define SHMSEG_REMOVED 0x0400
75 1.16 mycroft #define SHMSEG_ALLOCATED 0x0800
76 1.16 mycroft #define SHMSEG_WANTED 0x1000
77 1.11 hpeyerl
78 1.11 hpeyerl int shm_last_free, shm_nused, shm_committed;
79 1.11 hpeyerl
80 1.11 hpeyerl struct shm_handle {
81 1.42 mrg #ifdef UVM
82 1.42 mrg struct uvm_object *shm_object;
83 1.42 mrg #else
84 1.39 drochner vm_object_t shm_object;
85 1.42 mrg #endif
86 1.11 hpeyerl };
87 1.11 hpeyerl
88 1.11 hpeyerl struct shmmap_state {
89 1.11 hpeyerl vm_offset_t va;
90 1.11 hpeyerl int shmid;
91 1.11 hpeyerl };
92 1.11 hpeyerl
93 1.35 christos static int shm_find_segment_by_key __P((key_t));
94 1.12 mycroft static void shm_deallocate_segment __P((struct shmid_ds *));
95 1.41 thorpej static int shm_delete_mapping __P((struct vmspace *, struct shmmap_state *));
96 1.35 christos static int shmget_existing __P((struct proc *, struct sys_shmget_args *,
97 1.35 christos int, int, register_t *));
98 1.35 christos static int shmget_allocate_segment __P((struct proc *, struct sys_shmget_args *,
99 1.35 christos int, register_t *));
100 1.11 hpeyerl
101 1.12 mycroft static int
102 1.12 mycroft shm_find_segment_by_key(key)
103 1.11 hpeyerl key_t key;
104 1.11 hpeyerl {
105 1.11 hpeyerl int i;
106 1.11 hpeyerl
107 1.12 mycroft for (i = 0; i < shminfo.shmmni; i++)
108 1.12 mycroft if ((shmsegs[i].shm_perm.mode & SHMSEG_ALLOCATED) &&
109 1.12 mycroft shmsegs[i].shm_perm.key == key)
110 1.12 mycroft return i;
111 1.11 hpeyerl return -1;
112 1.11 hpeyerl }
113 1.11 hpeyerl
114 1.28 christos struct shmid_ds *
115 1.15 mycroft shm_find_segment_by_shmid(shmid)
116 1.11 hpeyerl int shmid;
117 1.11 hpeyerl {
118 1.11 hpeyerl int segnum;
119 1.11 hpeyerl struct shmid_ds *shmseg;
120 1.11 hpeyerl
121 1.11 hpeyerl segnum = IPCID_TO_IX(shmid);
122 1.12 mycroft if (segnum < 0 || segnum >= shminfo.shmmni)
123 1.11 hpeyerl return NULL;
124 1.11 hpeyerl shmseg = &shmsegs[segnum];
125 1.12 mycroft if ((shmseg->shm_perm.mode & (SHMSEG_ALLOCATED | SHMSEG_REMOVED))
126 1.12 mycroft != SHMSEG_ALLOCATED ||
127 1.12 mycroft shmseg->shm_perm.seq != IPCID_TO_SEQ(shmid))
128 1.11 hpeyerl return NULL;
129 1.11 hpeyerl return shmseg;
130 1.11 hpeyerl }
131 1.11 hpeyerl
132 1.12 mycroft static void
133 1.12 mycroft shm_deallocate_segment(shmseg)
134 1.12 mycroft struct shmid_ds *shmseg;
135 1.12 mycroft {
136 1.12 mycroft struct shm_handle *shm_handle;
137 1.14 mycroft size_t size;
138 1.12 mycroft
139 1.12 mycroft shm_handle = shmseg->shm_internal;
140 1.14 mycroft size = (shmseg->shm_segsz + CLOFSET) & ~CLOFSET;
141 1.42 mrg #ifdef UVM
142 1.42 mrg uao_detach(shm_handle->shm_object);
143 1.42 mrg #else
144 1.39 drochner vm_object_deallocate(shm_handle->shm_object);
145 1.42 mrg #endif
146 1.12 mycroft free((caddr_t)shm_handle, M_SHM);
147 1.12 mycroft shmseg->shm_internal = NULL;
148 1.14 mycroft shm_committed -= btoc(size);
149 1.12 mycroft shmseg->shm_perm.mode = SHMSEG_FREE;
150 1.25 mycroft shm_nused--;
151 1.12 mycroft }
152 1.12 mycroft
153 1.12 mycroft static int
154 1.41 thorpej shm_delete_mapping(vm, shmmap_s)
155 1.41 thorpej struct vmspace *vm;
156 1.11 hpeyerl struct shmmap_state *shmmap_s;
157 1.11 hpeyerl {
158 1.12 mycroft struct shmid_ds *shmseg;
159 1.12 mycroft int segnum, result;
160 1.14 mycroft size_t size;
161 1.11 hpeyerl
162 1.12 mycroft segnum = IPCID_TO_IX(shmmap_s->shmid);
163 1.12 mycroft shmseg = &shmsegs[segnum];
164 1.14 mycroft size = (shmseg->shm_segsz + CLOFSET) & ~CLOFSET;
165 1.42 mrg #ifdef UVM
166 1.45 thorpej result = uvm_deallocate(&vm->vm_map, shmmap_s->va, size);
167 1.42 mrg #else
168 1.41 thorpej result = vm_map_remove(&vm->vm_map,
169 1.40 drochner shmmap_s->va, shmmap_s->va + size);
170 1.42 mrg #endif
171 1.11 hpeyerl if (result != KERN_SUCCESS)
172 1.11 hpeyerl return EINVAL;
173 1.12 mycroft shmmap_s->shmid = -1;
174 1.11 hpeyerl shmseg->shm_dtime = time.tv_sec;
175 1.12 mycroft if ((--shmseg->shm_nattch <= 0) &&
176 1.11 hpeyerl (shmseg->shm_perm.mode & SHMSEG_REMOVED)) {
177 1.12 mycroft shm_deallocate_segment(shmseg);
178 1.12 mycroft shm_last_free = segnum;
179 1.11 hpeyerl }
180 1.11 hpeyerl return 0;
181 1.11 hpeyerl }
182 1.11 hpeyerl
183 1.12 mycroft int
184 1.33 mycroft sys_shmdt(p, v, retval)
185 1.11 hpeyerl struct proc *p;
186 1.32 thorpej void *v;
187 1.32 thorpej register_t *retval;
188 1.32 thorpej {
189 1.33 mycroft struct sys_shmdt_args /* {
190 1.44 kleink syscallarg(const void *) shmaddr;
191 1.32 thorpej } */ *uap = v;
192 1.12 mycroft struct shmmap_state *shmmap_s;
193 1.11 hpeyerl int i;
194 1.11 hpeyerl
195 1.12 mycroft shmmap_s = (struct shmmap_state *)p->p_vmspace->vm_shm;
196 1.38 christos if (shmmap_s == NULL)
197 1.38 christos return EINVAL;
198 1.38 christos
199 1.12 mycroft for (i = 0; i < shminfo.shmseg; i++, shmmap_s++)
200 1.12 mycroft if (shmmap_s->shmid != -1 &&
201 1.26 cgd shmmap_s->va == (vm_offset_t)SCARG(uap, shmaddr))
202 1.12 mycroft break;
203 1.11 hpeyerl if (i == shminfo.shmseg)
204 1.11 hpeyerl return EINVAL;
205 1.41 thorpej return shm_delete_mapping(p->p_vmspace, shmmap_s);
206 1.11 hpeyerl }
207 1.11 hpeyerl
208 1.12 mycroft int
209 1.33 mycroft sys_shmat(p, v, retval)
210 1.11 hpeyerl struct proc *p;
211 1.32 thorpej void *v;
212 1.32 thorpej register_t *retval;
213 1.32 thorpej {
214 1.33 mycroft struct sys_shmat_args /* {
215 1.26 cgd syscallarg(int) shmid;
216 1.44 kleink syscallarg(const void *) shmaddr;
217 1.35 christos syscallarg(int) shmflg;
218 1.32 thorpej } */ *uap = v;
219 1.12 mycroft int error, i, flags;
220 1.12 mycroft struct ucred *cred = p->p_ucred;
221 1.11 hpeyerl struct shmid_ds *shmseg;
222 1.11 hpeyerl struct shmmap_state *shmmap_s = NULL;
223 1.39 drochner struct shm_handle *shm_handle;
224 1.11 hpeyerl vm_offset_t attach_va;
225 1.11 hpeyerl vm_prot_t prot;
226 1.11 hpeyerl vm_size_t size;
227 1.39 drochner int rv;
228 1.11 hpeyerl
229 1.12 mycroft shmmap_s = (struct shmmap_state *)p->p_vmspace->vm_shm;
230 1.12 mycroft if (shmmap_s == NULL) {
231 1.12 mycroft size = shminfo.shmseg * sizeof(struct shmmap_state);
232 1.12 mycroft shmmap_s = malloc(size, M_SHM, M_WAITOK);
233 1.18 cgd for (i = 0; i < shminfo.shmseg; i++)
234 1.18 cgd shmmap_s[i].shmid = -1;
235 1.12 mycroft p->p_vmspace->vm_shm = (caddr_t)shmmap_s;
236 1.12 mycroft }
237 1.26 cgd shmseg = shm_find_segment_by_shmid(SCARG(uap, shmid));
238 1.11 hpeyerl if (shmseg == NULL)
239 1.11 hpeyerl return EINVAL;
240 1.35 christos error = ipcperm(cred, &shmseg->shm_perm,
241 1.35 christos (SCARG(uap, shmflg) & SHM_RDONLY) ? IPC_R : IPC_R|IPC_W);
242 1.35 christos if (error)
243 1.12 mycroft return error;
244 1.12 mycroft for (i = 0; i < shminfo.shmseg; i++) {
245 1.12 mycroft if (shmmap_s->shmid == -1)
246 1.12 mycroft break;
247 1.12 mycroft shmmap_s++;
248 1.11 hpeyerl }
249 1.12 mycroft if (i >= shminfo.shmseg)
250 1.12 mycroft return EMFILE;
251 1.14 mycroft size = (shmseg->shm_segsz + CLOFSET) & ~CLOFSET;
252 1.12 mycroft prot = VM_PROT_READ;
253 1.26 cgd if ((SCARG(uap, shmflg) & SHM_RDONLY) == 0)
254 1.12 mycroft prot |= VM_PROT_WRITE;
255 1.12 mycroft flags = MAP_ANON | MAP_SHARED;
256 1.26 cgd if (SCARG(uap, shmaddr)) {
257 1.12 mycroft flags |= MAP_FIXED;
258 1.26 cgd if (SCARG(uap, shmflg) & SHM_RND)
259 1.26 cgd attach_va =
260 1.26 cgd (vm_offset_t)SCARG(uap, shmaddr) & ~(SHMLBA-1);
261 1.26 cgd else if (((vm_offset_t)SCARG(uap, shmaddr) & (SHMLBA-1)) == 0)
262 1.26 cgd attach_va = (vm_offset_t)SCARG(uap, shmaddr);
263 1.11 hpeyerl else
264 1.14 mycroft return EINVAL;
265 1.12 mycroft } else {
266 1.20 mycroft /* This is just a hint to vm_mmap() about where to put it. */
267 1.31 cgd attach_va =
268 1.31 cgd round_page(p->p_vmspace->vm_taddr + MAXTSIZ + MAXDSIZ);
269 1.11 hpeyerl }
270 1.39 drochner shm_handle = shmseg->shm_internal;
271 1.42 mrg #ifdef UVM
272 1.42 mrg uao_reference(shm_handle->shm_object);
273 1.42 mrg rv = uvm_map(&p->p_vmspace->vm_map, &attach_va, size,
274 1.42 mrg shm_handle->shm_object, 0,
275 1.42 mrg UVM_MAPFLAG(prot, prot, UVM_INH_SHARE,
276 1.42 mrg UVM_ADV_RANDOM, 0));
277 1.42 mrg if (rv != KERN_SUCCESS) {
278 1.42 mrg return ENOMEM;
279 1.42 mrg }
280 1.42 mrg #else
281 1.39 drochner vm_object_reference(shm_handle->shm_object);
282 1.39 drochner rv = vm_map_find(&p->p_vmspace->vm_map, shm_handle->shm_object,
283 1.39 drochner 0, &attach_va, size, (flags & MAP_FIXED)?0:1);
284 1.39 drochner if (rv != KERN_SUCCESS) {
285 1.39 drochner return ENOMEM;
286 1.39 drochner }
287 1.39 drochner vm_map_protect(&p->p_vmspace->vm_map, attach_va, attach_va + size,
288 1.39 drochner prot, 0);
289 1.39 drochner vm_map_inherit(&p->p_vmspace->vm_map,
290 1.39 drochner attach_va, attach_va + size, VM_INHERIT_SHARE);
291 1.42 mrg #endif
292 1.39 drochner
293 1.12 mycroft shmmap_s->va = attach_va;
294 1.26 cgd shmmap_s->shmid = SCARG(uap, shmid);
295 1.11 hpeyerl shmseg->shm_lpid = p->p_pid;
296 1.11 hpeyerl shmseg->shm_atime = time.tv_sec;
297 1.11 hpeyerl shmseg->shm_nattch++;
298 1.12 mycroft *retval = attach_va;
299 1.11 hpeyerl return 0;
300 1.11 hpeyerl }
301 1.11 hpeyerl
302 1.12 mycroft int
303 1.33 mycroft sys_shmctl(p, v, retval)
304 1.11 hpeyerl struct proc *p;
305 1.32 thorpej void *v;
306 1.32 thorpej register_t *retval;
307 1.32 thorpej {
308 1.33 mycroft struct sys_shmctl_args /* {
309 1.26 cgd syscallarg(int) shmid;
310 1.26 cgd syscallarg(int) cmd;
311 1.26 cgd syscallarg(struct shmid_ds *) buf;
312 1.32 thorpej } */ *uap = v;
313 1.35 christos int error;
314 1.12 mycroft struct ucred *cred = p->p_ucred;
315 1.11 hpeyerl struct shmid_ds inbuf;
316 1.11 hpeyerl struct shmid_ds *shmseg;
317 1.11 hpeyerl
318 1.26 cgd shmseg = shm_find_segment_by_shmid(SCARG(uap, shmid));
319 1.11 hpeyerl if (shmseg == NULL)
320 1.11 hpeyerl return EINVAL;
321 1.26 cgd switch (SCARG(uap, cmd)) {
322 1.11 hpeyerl case IPC_STAT:
323 1.35 christos if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_R)) != 0)
324 1.11 hpeyerl return error;
325 1.35 christos error = copyout((caddr_t)shmseg, SCARG(uap, buf),
326 1.35 christos sizeof(inbuf));
327 1.35 christos if (error)
328 1.11 hpeyerl return error;
329 1.11 hpeyerl break;
330 1.11 hpeyerl case IPC_SET:
331 1.35 christos if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_M)) != 0)
332 1.13 mycroft return error;
333 1.35 christos error = copyin(SCARG(uap, buf), (caddr_t)&inbuf,
334 1.35 christos sizeof(inbuf));
335 1.35 christos if (error)
336 1.11 hpeyerl return error;
337 1.11 hpeyerl shmseg->shm_perm.uid = inbuf.shm_perm.uid;
338 1.11 hpeyerl shmseg->shm_perm.gid = inbuf.shm_perm.gid;
339 1.12 mycroft shmseg->shm_perm.mode =
340 1.12 mycroft (shmseg->shm_perm.mode & ~ACCESSPERMS) |
341 1.12 mycroft (inbuf.shm_perm.mode & ACCESSPERMS);
342 1.12 mycroft shmseg->shm_ctime = time.tv_sec;
343 1.11 hpeyerl break;
344 1.11 hpeyerl case IPC_RMID:
345 1.35 christos if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_M)) != 0)
346 1.13 mycroft return error;
347 1.12 mycroft shmseg->shm_perm.key = IPC_PRIVATE;
348 1.12 mycroft shmseg->shm_perm.mode |= SHMSEG_REMOVED;
349 1.12 mycroft if (shmseg->shm_nattch <= 0) {
350 1.12 mycroft shm_deallocate_segment(shmseg);
351 1.26 cgd shm_last_free = IPCID_TO_IX(SCARG(uap, shmid));
352 1.11 hpeyerl }
353 1.11 hpeyerl break;
354 1.11 hpeyerl case SHM_LOCK:
355 1.11 hpeyerl case SHM_UNLOCK:
356 1.11 hpeyerl default:
357 1.11 hpeyerl return EINVAL;
358 1.11 hpeyerl }
359 1.11 hpeyerl return 0;
360 1.11 hpeyerl }
361 1.11 hpeyerl
362 1.12 mycroft static int
363 1.12 mycroft shmget_existing(p, uap, mode, segnum, retval)
364 1.11 hpeyerl struct proc *p;
365 1.33 mycroft struct sys_shmget_args /* {
366 1.26 cgd syscallarg(key_t) key;
367 1.44 kleink syscallarg(size_t) size;
368 1.35 christos syscallarg(int) shmflg;
369 1.26 cgd } */ *uap;
370 1.11 hpeyerl int mode;
371 1.11 hpeyerl int segnum;
372 1.26 cgd register_t *retval;
373 1.11 hpeyerl {
374 1.12 mycroft struct shmid_ds *shmseg;
375 1.12 mycroft struct ucred *cred = p->p_ucred;
376 1.11 hpeyerl int error;
377 1.11 hpeyerl
378 1.11 hpeyerl shmseg = &shmsegs[segnum];
379 1.16 mycroft if (shmseg->shm_perm.mode & SHMSEG_REMOVED) {
380 1.16 mycroft /*
381 1.16 mycroft * This segment is in the process of being allocated. Wait
382 1.16 mycroft * until it's done, and look the key up again (in case the
383 1.16 mycroft * allocation failed or it was freed).
384 1.16 mycroft */
385 1.16 mycroft shmseg->shm_perm.mode |= SHMSEG_WANTED;
386 1.35 christos error = tsleep((caddr_t)shmseg, PLOCK | PCATCH, "shmget", 0);
387 1.35 christos if (error)
388 1.16 mycroft return error;
389 1.16 mycroft return EAGAIN;
390 1.16 mycroft }
391 1.35 christos if ((error = ipcperm(cred, &shmseg->shm_perm, mode)) != 0)
392 1.11 hpeyerl return error;
393 1.26 cgd if (SCARG(uap, size) && SCARG(uap, size) > shmseg->shm_segsz)
394 1.11 hpeyerl return EINVAL;
395 1.37 christos if ((SCARG(uap, shmflg) & (IPC_CREAT | IPC_EXCL)) ==
396 1.26 cgd (IPC_CREAT | IPC_EXCL))
397 1.12 mycroft return EEXIST;
398 1.11 hpeyerl *retval = IXSEQ_TO_IPCID(segnum, shmseg->shm_perm);
399 1.11 hpeyerl return 0;
400 1.11 hpeyerl }
401 1.11 hpeyerl
402 1.14 mycroft static int
403 1.14 mycroft shmget_allocate_segment(p, uap, mode, retval)
404 1.14 mycroft struct proc *p;
405 1.33 mycroft struct sys_shmget_args /* {
406 1.26 cgd syscallarg(key_t) key;
407 1.44 kleink syscallarg(size_t) size;
408 1.35 christos syscallarg(int) shmflg;
409 1.26 cgd } */ *uap;
410 1.14 mycroft int mode;
411 1.26 cgd register_t *retval;
412 1.14 mycroft {
413 1.39 drochner int i, segnum, shmid, size;
414 1.14 mycroft struct ucred *cred = p->p_ucred;
415 1.14 mycroft struct shmid_ds *shmseg;
416 1.14 mycroft struct shm_handle *shm_handle;
417 1.42 mrg #ifndef UVM
418 1.39 drochner vm_pager_t pager;
419 1.42 mrg #endif
420 1.40 drochner int error = 0;
421 1.14 mycroft
422 1.26 cgd if (SCARG(uap, size) < shminfo.shmmin ||
423 1.26 cgd SCARG(uap, size) > shminfo.shmmax)
424 1.14 mycroft return EINVAL;
425 1.14 mycroft if (shm_nused >= shminfo.shmmni) /* any shmids left? */
426 1.14 mycroft return ENOSPC;
427 1.26 cgd size = (SCARG(uap, size) + CLOFSET) & ~CLOFSET;
428 1.14 mycroft if (shm_committed + btoc(size) > shminfo.shmall)
429 1.14 mycroft return ENOMEM;
430 1.14 mycroft if (shm_last_free < 0) {
431 1.14 mycroft for (i = 0; i < shminfo.shmmni; i++)
432 1.14 mycroft if (shmsegs[i].shm_perm.mode & SHMSEG_FREE)
433 1.14 mycroft break;
434 1.14 mycroft if (i == shminfo.shmmni)
435 1.14 mycroft panic("shmseg free count inconsistent");
436 1.14 mycroft segnum = i;
437 1.14 mycroft } else {
438 1.14 mycroft segnum = shm_last_free;
439 1.14 mycroft shm_last_free = -1;
440 1.14 mycroft }
441 1.14 mycroft shmseg = &shmsegs[segnum];
442 1.14 mycroft /*
443 1.14 mycroft * In case we sleep in malloc(), mark the segment present but deleted
444 1.14 mycroft * so that noone else tries to create the same key.
445 1.14 mycroft */
446 1.14 mycroft shmseg->shm_perm.mode = SHMSEG_ALLOCATED | SHMSEG_REMOVED;
447 1.26 cgd shmseg->shm_perm.key = SCARG(uap, key);
448 1.14 mycroft shmseg->shm_perm.seq = (shmseg->shm_perm.seq + 1) & 0x7fff;
449 1.14 mycroft shm_handle = (struct shm_handle *)
450 1.14 mycroft malloc(sizeof(struct shm_handle), M_SHM, M_WAITOK);
451 1.14 mycroft shmid = IXSEQ_TO_IPCID(segnum, shmseg->shm_perm);
452 1.39 drochner
453 1.42 mrg
454 1.42 mrg #ifdef UVM
455 1.42 mrg shm_handle->shm_object = uao_create(size, 0);
456 1.42 mrg #else
457 1.39 drochner shm_handle->shm_object = vm_object_allocate(size);
458 1.39 drochner if (shm_handle->shm_object == NULL) {
459 1.40 drochner /* XXX cannot happen */
460 1.40 drochner error = ENOMEM;
461 1.40 drochner goto out;
462 1.39 drochner }
463 1.39 drochner /*
464 1.39 drochner * We make sure that we have allocated a pager before we need
465 1.39 drochner * to.
466 1.39 drochner */
467 1.39 drochner pager = vm_pager_allocate(PG_DFLT, 0, size, VM_PROT_DEFAULT, 0);
468 1.39 drochner if (pager == NULL) {
469 1.40 drochner error = ENOMEM;
470 1.40 drochner goto out;
471 1.14 mycroft }
472 1.39 drochner vm_object_setpager(shm_handle->shm_object, pager, 0, 0);
473 1.42 mrg #endif
474 1.42 mrg
475 1.14 mycroft shmseg->shm_internal = shm_handle;
476 1.14 mycroft shmseg->shm_perm.cuid = shmseg->shm_perm.uid = cred->cr_uid;
477 1.14 mycroft shmseg->shm_perm.cgid = shmseg->shm_perm.gid = cred->cr_gid;
478 1.16 mycroft shmseg->shm_perm.mode = (shmseg->shm_perm.mode & SHMSEG_WANTED) |
479 1.16 mycroft (mode & ACCESSPERMS) | SHMSEG_ALLOCATED;
480 1.26 cgd shmseg->shm_segsz = SCARG(uap, size);
481 1.14 mycroft shmseg->shm_cpid = p->p_pid;
482 1.14 mycroft shmseg->shm_lpid = shmseg->shm_nattch = 0;
483 1.14 mycroft shmseg->shm_atime = shmseg->shm_dtime = 0;
484 1.14 mycroft shmseg->shm_ctime = time.tv_sec;
485 1.14 mycroft shm_committed += btoc(size);
486 1.14 mycroft shm_nused++;
487 1.40 drochner
488 1.42 mrg #ifndef UVM
489 1.40 drochner out:
490 1.40 drochner if (error) {
491 1.40 drochner if (shm_handle->shm_object != NULL)
492 1.40 drochner vm_object_deallocate(shm_handle->shm_object);
493 1.40 drochner free(shm_handle, M_SHM);
494 1.40 drochner shmseg->shm_perm.mode = (shmseg->shm_perm.mode & SHMSEG_WANTED)
495 1.40 drochner | SHMSEG_FREE;
496 1.40 drochner } else
497 1.42 mrg #endif
498 1.40 drochner *retval = shmid;
499 1.16 mycroft if (shmseg->shm_perm.mode & SHMSEG_WANTED) {
500 1.16 mycroft /*
501 1.16 mycroft * Somebody else wanted this key while we were asleep. Wake
502 1.16 mycroft * them up now.
503 1.16 mycroft */
504 1.16 mycroft shmseg->shm_perm.mode &= ~SHMSEG_WANTED;
505 1.16 mycroft wakeup((caddr_t)shmseg);
506 1.16 mycroft }
507 1.40 drochner return error;
508 1.14 mycroft }
509 1.14 mycroft
510 1.12 mycroft int
511 1.33 mycroft sys_shmget(p, v, retval)
512 1.11 hpeyerl struct proc *p;
513 1.32 thorpej void *v;
514 1.32 thorpej register_t *retval;
515 1.32 thorpej {
516 1.33 mycroft struct sys_shmget_args /* {
517 1.26 cgd syscallarg(key_t) key;
518 1.26 cgd syscallarg(int) size;
519 1.35 christos syscallarg(int) shmflg;
520 1.32 thorpej } */ *uap = v;
521 1.11 hpeyerl int segnum, mode, error;
522 1.11 hpeyerl
523 1.26 cgd mode = SCARG(uap, shmflg) & ACCESSPERMS;
524 1.26 cgd if (SCARG(uap, key) != IPC_PRIVATE) {
525 1.16 mycroft again:
526 1.26 cgd segnum = shm_find_segment_by_key(SCARG(uap, key));
527 1.16 mycroft if (segnum >= 0) {
528 1.16 mycroft error = shmget_existing(p, uap, mode, segnum, retval);
529 1.16 mycroft if (error == EAGAIN)
530 1.16 mycroft goto again;
531 1.16 mycroft return error;
532 1.16 mycroft }
533 1.26 cgd if ((SCARG(uap, shmflg) & IPC_CREAT) == 0)
534 1.14 mycroft return ENOENT;
535 1.11 hpeyerl }
536 1.14 mycroft return shmget_allocate_segment(p, uap, mode, retval);
537 1.11 hpeyerl }
538 1.11 hpeyerl
539 1.12 mycroft void
540 1.41 thorpej shmfork(vm1, vm2)
541 1.41 thorpej struct vmspace *vm1, *vm2;
542 1.11 hpeyerl {
543 1.11 hpeyerl struct shmmap_state *shmmap_s;
544 1.12 mycroft size_t size;
545 1.11 hpeyerl int i;
546 1.11 hpeyerl
547 1.41 thorpej if (vm1->vm_shm == NULL) {
548 1.41 thorpej vm2->vm_shm = NULL;
549 1.38 christos return;
550 1.38 christos }
551 1.41 thorpej
552 1.12 mycroft size = shminfo.shmseg * sizeof(struct shmmap_state);
553 1.12 mycroft shmmap_s = malloc(size, M_SHM, M_WAITOK);
554 1.46 perry memcpy(shmmap_s, vm1->vm_shm, size);
555 1.41 thorpej vm2->vm_shm = (caddr_t)shmmap_s;
556 1.12 mycroft for (i = 0; i < shminfo.shmseg; i++, shmmap_s++)
557 1.12 mycroft if (shmmap_s->shmid != -1)
558 1.11 hpeyerl shmsegs[IPCID_TO_IX(shmmap_s->shmid)].shm_nattch++;
559 1.11 hpeyerl }
560 1.11 hpeyerl
561 1.12 mycroft void
562 1.41 thorpej shmexit(vm)
563 1.41 thorpej struct vmspace *vm;
564 1.11 hpeyerl {
565 1.12 mycroft struct shmmap_state *shmmap_s;
566 1.11 hpeyerl int i;
567 1.11 hpeyerl
568 1.41 thorpej shmmap_s = (struct shmmap_state *)vm->vm_shm;
569 1.38 christos if (shmmap_s == NULL)
570 1.38 christos return;
571 1.12 mycroft for (i = 0; i < shminfo.shmseg; i++, shmmap_s++)
572 1.12 mycroft if (shmmap_s->shmid != -1)
573 1.41 thorpej shm_delete_mapping(vm, shmmap_s);
574 1.41 thorpej free(vm->vm_shm, M_SHM);
575 1.41 thorpej vm->vm_shm = NULL;
576 1.11 hpeyerl }
577 1.11 hpeyerl
578 1.12 mycroft void
579 1.12 mycroft shminit()
580 1.11 hpeyerl {
581 1.11 hpeyerl int i;
582 1.24 deraadt
583 1.24 deraadt shminfo.shmmax *= NBPG;
584 1.11 hpeyerl
585 1.11 hpeyerl for (i = 0; i < shminfo.shmmni; i++) {
586 1.11 hpeyerl shmsegs[i].shm_perm.mode = SHMSEG_FREE;
587 1.11 hpeyerl shmsegs[i].shm_perm.seq = 0;
588 1.11 hpeyerl }
589 1.11 hpeyerl shm_last_free = 0;
590 1.11 hpeyerl shm_nused = 0;
591 1.11 hpeyerl shm_committed = 0;
592 1.11 hpeyerl }
593