19454b2d8SWarner Losh /*- 2efaa6588SAlfred Perlstein * Copyright (c) 2002 Alfred Perlstein <alfred@FreeBSD.org> 3590f242cSRobert Watson * Copyright (c) 2005 Robert N. M. Watson 4efaa6588SAlfred Perlstein * All rights reserved. 5efaa6588SAlfred Perlstein * 6efaa6588SAlfred Perlstein * Redistribution and use in source and binary forms, with or without 7efaa6588SAlfred Perlstein * modification, are permitted provided that the following conditions 8efaa6588SAlfred Perlstein * are met: 9efaa6588SAlfred Perlstein * 1. Redistributions of source code must retain the above copyright 10efaa6588SAlfred Perlstein * notice, this list of conditions and the following disclaimer. 11efaa6588SAlfred Perlstein * 2. Redistributions in binary form must reproduce the above copyright 12efaa6588SAlfred Perlstein * notice, this list of conditions and the following disclaimer in the 13efaa6588SAlfred Perlstein * documentation and/or other materials provided with the distribution. 14efaa6588SAlfred Perlstein * 15efaa6588SAlfred Perlstein * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16efaa6588SAlfred Perlstein * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17efaa6588SAlfred Perlstein * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18efaa6588SAlfred Perlstein * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19efaa6588SAlfred Perlstein * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20efaa6588SAlfred Perlstein * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21efaa6588SAlfred Perlstein * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22efaa6588SAlfred Perlstein * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23efaa6588SAlfred Perlstein * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24efaa6588SAlfred Perlstein * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25efaa6588SAlfred Perlstein * SUCH DAMAGE. 26efaa6588SAlfred Perlstein */ 27efaa6588SAlfred Perlstein 28677b542eSDavid E. O'Brien #include <sys/cdefs.h> 29677b542eSDavid E. O'Brien __FBSDID("$FreeBSD$"); 30677b542eSDavid E. O'Brien 31efaa6588SAlfred Perlstein #include "opt_posix.h" 32efaa6588SAlfred Perlstein 33efaa6588SAlfred Perlstein #include <sys/param.h> 34efaa6588SAlfred Perlstein #include <sys/systm.h> 35efaa6588SAlfred Perlstein #include <sys/sysproto.h> 3675b8b3b2SJohn Baldwin #include <sys/eventhandler.h> 37efaa6588SAlfred Perlstein #include <sys/kernel.h> 38efaa6588SAlfred Perlstein #include <sys/proc.h> 39efaa6588SAlfred Perlstein #include <sys/lock.h> 40efaa6588SAlfred Perlstein #include <sys/mutex.h> 4177409fe1SPoul-Henning Kamp #include <sys/module.h> 42efaa6588SAlfred Perlstein #include <sys/condvar.h> 43efaa6588SAlfred Perlstein #include <sys/sem.h> 44efaa6588SAlfred Perlstein #include <sys/uio.h> 45efaa6588SAlfred Perlstein #include <sys/syscall.h> 46efaa6588SAlfred Perlstein #include <sys/stat.h> 47efaa6588SAlfred Perlstein #include <sys/sysent.h> 48efaa6588SAlfred Perlstein #include <sys/sysctl.h> 49aae94fbbSDaniel Eischen #include <sys/time.h> 50efaa6588SAlfred Perlstein #include <sys/malloc.h> 51efaa6588SAlfred Perlstein #include <sys/fcntl.h> 52efaa6588SAlfred Perlstein 53efaa6588SAlfred Perlstein #include <posix4/posix4.h> 54efaa6588SAlfred Perlstein #include <posix4/semaphore.h> 55efaa6588SAlfred Perlstein #include <posix4/_semaphore.h> 56efaa6588SAlfred Perlstein 57590f242cSRobert Watson static int sem_count_proc(struct proc *p); 58efaa6588SAlfred Perlstein static struct ksem *sem_lookup_byname(const char *name); 59efaa6588SAlfred Perlstein static int sem_create(struct thread *td, const char *name, 60efaa6588SAlfred Perlstein struct ksem **ksret, mode_t mode, unsigned int value); 61efaa6588SAlfred Perlstein static void sem_free(struct ksem *ksnew); 62b2546660SJohn Baldwin static int sem_perm(struct thread *td, struct ksem *ks); 63efaa6588SAlfred Perlstein static void sem_enter(struct proc *p, struct ksem *ks); 64efaa6588SAlfred Perlstein static int sem_leave(struct proc *p, struct ksem *ks); 6575b8b3b2SJohn Baldwin static void sem_exithook(void *arg, struct proc *p); 66590f242cSRobert Watson static void sem_forkhook(void *arg, struct proc *p1, struct proc *p2, 67590f242cSRobert Watson int flags); 68b2546660SJohn Baldwin static int sem_hasopen(struct thread *td, struct ksem *ks); 69efaa6588SAlfred Perlstein 70efaa6588SAlfred Perlstein static int kern_sem_close(struct thread *td, semid_t id); 71efaa6588SAlfred Perlstein static int kern_sem_post(struct thread *td, semid_t id); 72aae94fbbSDaniel Eischen static int kern_sem_wait(struct thread *td, semid_t id, int tryflag, 73aae94fbbSDaniel Eischen struct timespec *abstime); 74efaa6588SAlfred Perlstein static int kern_sem_init(struct thread *td, int dir, unsigned int value, 75efaa6588SAlfred Perlstein semid_t *idp); 76efaa6588SAlfred Perlstein static int kern_sem_open(struct thread *td, int dir, const char *name, 77efaa6588SAlfred Perlstein int oflag, mode_t mode, unsigned int value, semid_t *idp); 78efaa6588SAlfred Perlstein static int kern_sem_unlink(struct thread *td, const char *name); 79efaa6588SAlfred Perlstein 80efaa6588SAlfred Perlstein #ifndef SEM_MAX 81efaa6588SAlfred Perlstein #define SEM_MAX 30 82efaa6588SAlfred Perlstein #endif 83efaa6588SAlfred Perlstein 84efaa6588SAlfred Perlstein #define SEM_MAX_NAMELEN 14 85efaa6588SAlfred Perlstein 86efaa6588SAlfred Perlstein #define SEM_TO_ID(x) ((intptr_t)(x)) 87efaa6588SAlfred Perlstein #define ID_TO_SEM(x) id_to_sem(x) 88efaa6588SAlfred Perlstein 89efaa6588SAlfred Perlstein struct kuser { 90efaa6588SAlfred Perlstein pid_t ku_pid; 91efaa6588SAlfred Perlstein LIST_ENTRY(kuser) ku_next; 92efaa6588SAlfred Perlstein }; 93efaa6588SAlfred Perlstein 94efaa6588SAlfred Perlstein struct ksem { 95efaa6588SAlfred Perlstein LIST_ENTRY(ksem) ks_entry; /* global list entry */ 96efaa6588SAlfred Perlstein int ks_onlist; /* boolean if on a list (ks_entry) */ 97efaa6588SAlfred Perlstein char *ks_name; /* if named, this is the name */ 98efaa6588SAlfred Perlstein int ks_ref; /* number of references */ 99efaa6588SAlfred Perlstein mode_t ks_mode; /* protection bits */ 100efaa6588SAlfred Perlstein uid_t ks_uid; /* creator uid */ 101efaa6588SAlfred Perlstein gid_t ks_gid; /* creator gid */ 102efaa6588SAlfred Perlstein unsigned int ks_value; /* current value */ 103efaa6588SAlfred Perlstein struct cv ks_cv; /* waiters sleep here */ 104efaa6588SAlfred Perlstein int ks_waiters; /* number of waiters */ 105efaa6588SAlfred Perlstein LIST_HEAD(, kuser) ks_users; /* pids using this sem */ 106efaa6588SAlfred Perlstein }; 107efaa6588SAlfred Perlstein 108efaa6588SAlfred Perlstein /* 109efaa6588SAlfred Perlstein * available semaphores go here, this includes sem_init and any semaphores 110efaa6588SAlfred Perlstein * created via sem_open that have not yet been unlinked. 111efaa6588SAlfred Perlstein */ 112efaa6588SAlfred Perlstein LIST_HEAD(, ksem) ksem_head = LIST_HEAD_INITIALIZER(&ksem_head); 113efaa6588SAlfred Perlstein /* 114efaa6588SAlfred Perlstein * semaphores still in use but have been sem_unlink()'d go here. 115efaa6588SAlfred Perlstein */ 116efaa6588SAlfred Perlstein LIST_HEAD(, ksem) ksem_deadhead = LIST_HEAD_INITIALIZER(&ksem_deadhead); 117efaa6588SAlfred Perlstein 118efaa6588SAlfred Perlstein static struct mtx sem_lock; 119efaa6588SAlfred Perlstein static MALLOC_DEFINE(M_SEM, "sems", "semaphore data"); 120efaa6588SAlfred Perlstein 121efaa6588SAlfred Perlstein static int nsems = 0; 122efaa6588SAlfred Perlstein SYSCTL_DECL(_p1003_1b); 123efaa6588SAlfred Perlstein SYSCTL_INT(_p1003_1b, OID_AUTO, nsems, CTLFLAG_RD, &nsems, 0, ""); 124efaa6588SAlfred Perlstein 125590f242cSRobert Watson static eventhandler_tag sem_exit_tag, sem_exec_tag, sem_fork_tag; 12675b8b3b2SJohn Baldwin 127c814aa3fSAlfred Perlstein #ifdef SEM_DEBUG 128c814aa3fSAlfred Perlstein #define DP(x) printf x 129c814aa3fSAlfred Perlstein #else 130c814aa3fSAlfred Perlstein #define DP(x) 131c814aa3fSAlfred Perlstein #endif 132c814aa3fSAlfred Perlstein 133efaa6588SAlfred Perlstein static __inline 134efaa6588SAlfred Perlstein void 135efaa6588SAlfred Perlstein sem_ref(struct ksem *ks) 136efaa6588SAlfred Perlstein { 137efaa6588SAlfred Perlstein 1380fddf92dSRobert Watson mtx_assert(&sem_lock, MA_OWNED); 139efaa6588SAlfred Perlstein ks->ks_ref++; 140c814aa3fSAlfred Perlstein DP(("sem_ref: ks = %p, ref = %d\n", ks, ks->ks_ref)); 141efaa6588SAlfred Perlstein } 142efaa6588SAlfred Perlstein 143efaa6588SAlfred Perlstein static __inline 144efaa6588SAlfred Perlstein void 145efaa6588SAlfred Perlstein sem_rel(struct ksem *ks) 146efaa6588SAlfred Perlstein { 147efaa6588SAlfred Perlstein 1480fddf92dSRobert Watson mtx_assert(&sem_lock, MA_OWNED); 149c814aa3fSAlfred Perlstein DP(("sem_rel: ks = %p, ref = %d\n", ks, ks->ks_ref - 1)); 150efaa6588SAlfred Perlstein if (--ks->ks_ref == 0) 151efaa6588SAlfred Perlstein sem_free(ks); 152efaa6588SAlfred Perlstein } 153efaa6588SAlfred Perlstein 154efaa6588SAlfred Perlstein static __inline struct ksem *id_to_sem(semid_t id); 155efaa6588SAlfred Perlstein 156efaa6588SAlfred Perlstein static __inline 157efaa6588SAlfred Perlstein struct ksem * 158efaa6588SAlfred Perlstein id_to_sem(id) 159efaa6588SAlfred Perlstein semid_t id; 160efaa6588SAlfred Perlstein { 161efaa6588SAlfred Perlstein struct ksem *ks; 162efaa6588SAlfred Perlstein 163955ec415SRobert Watson mtx_assert(&sem_lock, MA_OWNED); 164c814aa3fSAlfred Perlstein DP(("id_to_sem: id = %0x,%p\n", id, (struct ksem *)id)); 165efaa6588SAlfred Perlstein LIST_FOREACH(ks, &ksem_head, ks_entry) { 166c814aa3fSAlfred Perlstein DP(("id_to_sem: ks = %p\n", ks)); 167efaa6588SAlfred Perlstein if (ks == (struct ksem *)id) 168efaa6588SAlfred Perlstein return (ks); 169efaa6588SAlfred Perlstein } 170efaa6588SAlfred Perlstein return (NULL); 171efaa6588SAlfred Perlstein } 172efaa6588SAlfred Perlstein 173c3053131SPoul-Henning Kamp static struct ksem * 174efaa6588SAlfred Perlstein sem_lookup_byname(name) 175efaa6588SAlfred Perlstein const char *name; 176efaa6588SAlfred Perlstein { 177efaa6588SAlfred Perlstein struct ksem *ks; 178efaa6588SAlfred Perlstein 179955ec415SRobert Watson mtx_assert(&sem_lock, MA_OWNED); 180efaa6588SAlfred Perlstein LIST_FOREACH(ks, &ksem_head, ks_entry) 181efaa6588SAlfred Perlstein if (ks->ks_name != NULL && strcmp(ks->ks_name, name) == 0) 182efaa6588SAlfred Perlstein return (ks); 183efaa6588SAlfred Perlstein return (NULL); 184efaa6588SAlfred Perlstein } 185efaa6588SAlfred Perlstein 186c3053131SPoul-Henning Kamp static int 187efaa6588SAlfred Perlstein sem_create(td, name, ksret, mode, value) 188efaa6588SAlfred Perlstein struct thread *td; 189efaa6588SAlfred Perlstein const char *name; 190efaa6588SAlfred Perlstein struct ksem **ksret; 191efaa6588SAlfred Perlstein mode_t mode; 192efaa6588SAlfred Perlstein unsigned int value; 193efaa6588SAlfred Perlstein { 194efaa6588SAlfred Perlstein struct ksem *ret; 195efaa6588SAlfred Perlstein struct proc *p; 196efaa6588SAlfred Perlstein struct ucred *uc; 197efaa6588SAlfred Perlstein size_t len; 198efaa6588SAlfred Perlstein int error; 199efaa6588SAlfred Perlstein 200c814aa3fSAlfred Perlstein DP(("sem_create\n")); 201efaa6588SAlfred Perlstein p = td->td_proc; 202b2546660SJohn Baldwin uc = td->td_ucred; 203efaa6588SAlfred Perlstein if (value > SEM_VALUE_MAX) 204efaa6588SAlfred Perlstein return (EINVAL); 205a163d034SWarner Losh ret = malloc(sizeof(*ret), M_SEM, M_WAITOK | M_ZERO); 206efaa6588SAlfred Perlstein if (name != NULL) { 207efaa6588SAlfred Perlstein len = strlen(name); 208efaa6588SAlfred Perlstein if (len > SEM_MAX_NAMELEN) { 209efaa6588SAlfred Perlstein free(ret, M_SEM); 210efaa6588SAlfred Perlstein return (ENAMETOOLONG); 211efaa6588SAlfred Perlstein } 212efaa6588SAlfred Perlstein /* name must start with a '/' but not contain one. */ 213efaa6588SAlfred Perlstein if (*name != '/' || len < 2 || index(name + 1, '/') != NULL) { 214efaa6588SAlfred Perlstein free(ret, M_SEM); 215efaa6588SAlfred Perlstein return (EINVAL); 216efaa6588SAlfred Perlstein } 217a163d034SWarner Losh ret->ks_name = malloc(len + 1, M_SEM, M_WAITOK); 218efaa6588SAlfred Perlstein strcpy(ret->ks_name, name); 219efaa6588SAlfred Perlstein } else { 220efaa6588SAlfred Perlstein ret->ks_name = NULL; 221efaa6588SAlfred Perlstein } 222efaa6588SAlfred Perlstein ret->ks_mode = mode; 223efaa6588SAlfred Perlstein ret->ks_value = value; 224efaa6588SAlfred Perlstein ret->ks_ref = 1; 225efaa6588SAlfred Perlstein ret->ks_waiters = 0; 226efaa6588SAlfred Perlstein ret->ks_uid = uc->cr_uid; 227efaa6588SAlfred Perlstein ret->ks_gid = uc->cr_gid; 228efaa6588SAlfred Perlstein ret->ks_onlist = 0; 229efaa6588SAlfred Perlstein cv_init(&ret->ks_cv, "sem"); 230efaa6588SAlfred Perlstein LIST_INIT(&ret->ks_users); 231efaa6588SAlfred Perlstein if (name != NULL) 232efaa6588SAlfred Perlstein sem_enter(td->td_proc, ret); 233efaa6588SAlfred Perlstein *ksret = ret; 234efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 235efaa6588SAlfred Perlstein if (nsems >= p31b_getcfg(CTL_P1003_1B_SEM_NSEMS_MAX)) { 236efaa6588SAlfred Perlstein sem_leave(td->td_proc, ret); 237efaa6588SAlfred Perlstein sem_free(ret); 238efaa6588SAlfred Perlstein error = ENFILE; 239efaa6588SAlfred Perlstein } else { 240efaa6588SAlfred Perlstein nsems++; 241efaa6588SAlfred Perlstein error = 0; 242efaa6588SAlfred Perlstein } 243efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 244efaa6588SAlfred Perlstein return (error); 245efaa6588SAlfred Perlstein } 246efaa6588SAlfred Perlstein 247efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 248efaa6588SAlfred Perlstein struct ksem_init_args { 249efaa6588SAlfred Perlstein unsigned int value; 250efaa6588SAlfred Perlstein semid_t *idp; 251efaa6588SAlfred Perlstein }; 252efaa6588SAlfred Perlstein int ksem_init(struct thread *td, struct ksem_init_args *uap); 253efaa6588SAlfred Perlstein #endif 254efaa6588SAlfred Perlstein int 255efaa6588SAlfred Perlstein ksem_init(td, uap) 256efaa6588SAlfred Perlstein struct thread *td; 257efaa6588SAlfred Perlstein struct ksem_init_args *uap; 258efaa6588SAlfred Perlstein { 259efaa6588SAlfred Perlstein int error; 260efaa6588SAlfred Perlstein 261efaa6588SAlfred Perlstein error = kern_sem_init(td, UIO_USERSPACE, uap->value, uap->idp); 262efaa6588SAlfred Perlstein return (error); 263efaa6588SAlfred Perlstein } 264efaa6588SAlfred Perlstein 265efaa6588SAlfred Perlstein static int 266efaa6588SAlfred Perlstein kern_sem_init(td, dir, value, idp) 267efaa6588SAlfred Perlstein struct thread *td; 268efaa6588SAlfred Perlstein int dir; 269efaa6588SAlfred Perlstein unsigned int value; 270efaa6588SAlfred Perlstein semid_t *idp; 271efaa6588SAlfred Perlstein { 272efaa6588SAlfred Perlstein struct ksem *ks; 273efaa6588SAlfred Perlstein semid_t id; 274efaa6588SAlfred Perlstein int error; 275efaa6588SAlfred Perlstein 276efaa6588SAlfred Perlstein error = sem_create(td, NULL, &ks, S_IRWXU | S_IRWXG, value); 277efaa6588SAlfred Perlstein if (error) 278efaa6588SAlfred Perlstein return (error); 279efaa6588SAlfred Perlstein id = SEM_TO_ID(ks); 280efaa6588SAlfred Perlstein if (dir == UIO_USERSPACE) { 281efaa6588SAlfred Perlstein error = copyout(&id, idp, sizeof(id)); 282efaa6588SAlfred Perlstein if (error) { 283efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 284efaa6588SAlfred Perlstein sem_rel(ks); 285efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 286efaa6588SAlfred Perlstein return (error); 287efaa6588SAlfred Perlstein } 288efaa6588SAlfred Perlstein } else { 289efaa6588SAlfred Perlstein *idp = id; 290efaa6588SAlfred Perlstein } 291efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 292efaa6588SAlfred Perlstein LIST_INSERT_HEAD(&ksem_head, ks, ks_entry); 293efaa6588SAlfred Perlstein ks->ks_onlist = 1; 294efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 295efaa6588SAlfred Perlstein return (error); 296efaa6588SAlfred Perlstein } 297efaa6588SAlfred Perlstein 298efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 299efaa6588SAlfred Perlstein struct ksem_open_args { 300efaa6588SAlfred Perlstein char *name; 301efaa6588SAlfred Perlstein int oflag; 302efaa6588SAlfred Perlstein mode_t mode; 303efaa6588SAlfred Perlstein unsigned int value; 304efaa6588SAlfred Perlstein semid_t *idp; 305efaa6588SAlfred Perlstein }; 306efaa6588SAlfred Perlstein int ksem_open(struct thread *td, struct ksem_open_args *uap); 307efaa6588SAlfred Perlstein #endif 308efaa6588SAlfred Perlstein int 309efaa6588SAlfred Perlstein ksem_open(td, uap) 310efaa6588SAlfred Perlstein struct thread *td; 311efaa6588SAlfred Perlstein struct ksem_open_args *uap; 312efaa6588SAlfred Perlstein { 313efaa6588SAlfred Perlstein char name[SEM_MAX_NAMELEN + 1]; 314efaa6588SAlfred Perlstein size_t done; 315efaa6588SAlfred Perlstein int error; 316efaa6588SAlfred Perlstein 317efaa6588SAlfred Perlstein error = copyinstr(uap->name, name, SEM_MAX_NAMELEN + 1, &done); 318efaa6588SAlfred Perlstein if (error) 319efaa6588SAlfred Perlstein return (error); 320c814aa3fSAlfred Perlstein DP((">>> sem_open start\n")); 321efaa6588SAlfred Perlstein error = kern_sem_open(td, UIO_USERSPACE, 322efaa6588SAlfred Perlstein name, uap->oflag, uap->mode, uap->value, uap->idp); 323c814aa3fSAlfred Perlstein DP(("<<< sem_open end\n")); 324efaa6588SAlfred Perlstein return (error); 325efaa6588SAlfred Perlstein } 326efaa6588SAlfred Perlstein 327efaa6588SAlfred Perlstein static int 328efaa6588SAlfred Perlstein kern_sem_open(td, dir, name, oflag, mode, value, idp) 329efaa6588SAlfred Perlstein struct thread *td; 330efaa6588SAlfred Perlstein int dir; 331efaa6588SAlfred Perlstein const char *name; 332efaa6588SAlfred Perlstein int oflag; 333efaa6588SAlfred Perlstein mode_t mode; 334efaa6588SAlfred Perlstein unsigned int value; 335efaa6588SAlfred Perlstein semid_t *idp; 336efaa6588SAlfred Perlstein { 337efaa6588SAlfred Perlstein struct ksem *ksnew, *ks; 338efaa6588SAlfred Perlstein int error; 339efaa6588SAlfred Perlstein semid_t id; 340efaa6588SAlfred Perlstein 341efaa6588SAlfred Perlstein ksnew = NULL; 342efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 343efaa6588SAlfred Perlstein ks = sem_lookup_byname(name); 344efaa6588SAlfred Perlstein /* 345efaa6588SAlfred Perlstein * If we found it but O_EXCL is set, error. 346efaa6588SAlfred Perlstein */ 347efaa6588SAlfred Perlstein if (ks != NULL && (oflag & O_EXCL) != 0) { 348efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 349efaa6588SAlfred Perlstein return (EEXIST); 350efaa6588SAlfred Perlstein } 351efaa6588SAlfred Perlstein /* 352efaa6588SAlfred Perlstein * If we didn't find it... 353efaa6588SAlfred Perlstein */ 354efaa6588SAlfred Perlstein if (ks == NULL) { 355efaa6588SAlfred Perlstein /* 356efaa6588SAlfred Perlstein * didn't ask for creation? error. 357efaa6588SAlfred Perlstein */ 358efaa6588SAlfred Perlstein if ((oflag & O_CREAT) == 0) { 359efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 360efaa6588SAlfred Perlstein return (ENOENT); 361efaa6588SAlfred Perlstein } 362efaa6588SAlfred Perlstein /* 363efaa6588SAlfred Perlstein * We may block during creation, so drop the lock. 364efaa6588SAlfred Perlstein */ 365efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 366efaa6588SAlfred Perlstein error = sem_create(td, name, &ksnew, mode, value); 367efaa6588SAlfred Perlstein if (error != 0) 368efaa6588SAlfred Perlstein return (error); 369efaa6588SAlfred Perlstein id = SEM_TO_ID(ksnew); 370efaa6588SAlfred Perlstein if (dir == UIO_USERSPACE) { 371c814aa3fSAlfred Perlstein DP(("about to copyout! %d to %p\n", id, idp)); 372efaa6588SAlfred Perlstein error = copyout(&id, idp, sizeof(id)); 373efaa6588SAlfred Perlstein if (error) { 374efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 375efaa6588SAlfred Perlstein sem_leave(td->td_proc, ksnew); 376efaa6588SAlfred Perlstein sem_rel(ksnew); 377efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 378efaa6588SAlfred Perlstein return (error); 379efaa6588SAlfred Perlstein } 380efaa6588SAlfred Perlstein } else { 381c814aa3fSAlfred Perlstein DP(("about to set! %d to %p\n", id, idp)); 382efaa6588SAlfred Perlstein *idp = id; 383efaa6588SAlfred Perlstein } 384efaa6588SAlfred Perlstein /* 385efaa6588SAlfred Perlstein * We need to make sure we haven't lost a race while 386efaa6588SAlfred Perlstein * allocating during creation. 387efaa6588SAlfred Perlstein */ 388efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 389efaa6588SAlfred Perlstein ks = sem_lookup_byname(name); 390efaa6588SAlfred Perlstein if (ks != NULL) { 391efaa6588SAlfred Perlstein /* we lost... */ 392efaa6588SAlfred Perlstein sem_leave(td->td_proc, ksnew); 393efaa6588SAlfred Perlstein sem_rel(ksnew); 394efaa6588SAlfred Perlstein /* we lost and we can't loose... */ 395efaa6588SAlfred Perlstein if ((oflag & O_EXCL) != 0) { 396efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 397efaa6588SAlfred Perlstein return (EEXIST); 398efaa6588SAlfred Perlstein } 399efaa6588SAlfred Perlstein } else { 400c814aa3fSAlfred Perlstein DP(("sem_create: about to add to list...\n")); 401efaa6588SAlfred Perlstein LIST_INSERT_HEAD(&ksem_head, ksnew, ks_entry); 402c814aa3fSAlfred Perlstein DP(("sem_create: setting list bit...\n")); 403efaa6588SAlfred Perlstein ksnew->ks_onlist = 1; 404c814aa3fSAlfred Perlstein DP(("sem_create: done, about to unlock...\n")); 405efaa6588SAlfred Perlstein } 406efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 407efaa6588SAlfred Perlstein } else { 408efaa6588SAlfred Perlstein /* 409efaa6588SAlfred Perlstein * if we aren't the creator, then enforce permissions. 410efaa6588SAlfred Perlstein */ 411b2546660SJohn Baldwin error = sem_perm(td, ks); 412efaa6588SAlfred Perlstein if (!error) 413efaa6588SAlfred Perlstein sem_ref(ks); 414efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 415efaa6588SAlfred Perlstein if (error) 416efaa6588SAlfred Perlstein return (error); 417efaa6588SAlfred Perlstein id = SEM_TO_ID(ks); 418efaa6588SAlfred Perlstein if (dir == UIO_USERSPACE) { 419efaa6588SAlfred Perlstein error = copyout(&id, idp, sizeof(id)); 420efaa6588SAlfred Perlstein if (error) { 421efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 422efaa6588SAlfred Perlstein sem_rel(ks); 423efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 424efaa6588SAlfred Perlstein return (error); 425efaa6588SAlfred Perlstein } 426efaa6588SAlfred Perlstein } else { 427efaa6588SAlfred Perlstein *idp = id; 428efaa6588SAlfred Perlstein } 429efaa6588SAlfred Perlstein sem_enter(td->td_proc, ks); 430efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 431efaa6588SAlfred Perlstein sem_rel(ks); 432efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 433efaa6588SAlfred Perlstein } 434efaa6588SAlfred Perlstein return (error); 435efaa6588SAlfred Perlstein } 436efaa6588SAlfred Perlstein 437c3053131SPoul-Henning Kamp static int 438b2546660SJohn Baldwin sem_perm(td, ks) 439b2546660SJohn Baldwin struct thread *td; 440efaa6588SAlfred Perlstein struct ksem *ks; 441efaa6588SAlfred Perlstein { 442efaa6588SAlfred Perlstein struct ucred *uc; 443efaa6588SAlfred Perlstein 444b2546660SJohn Baldwin uc = td->td_ucred; 445c814aa3fSAlfred Perlstein DP(("sem_perm: uc(%d,%d) ks(%d,%d,%o)\n", 446efaa6588SAlfred Perlstein uc->cr_uid, uc->cr_gid, 447c814aa3fSAlfred Perlstein ks->ks_uid, ks->ks_gid, ks->ks_mode)); 448efaa6588SAlfred Perlstein if ((uc->cr_uid == ks->ks_uid && (ks->ks_mode & S_IWUSR) != 0) || 449efaa6588SAlfred Perlstein (uc->cr_gid == ks->ks_gid && (ks->ks_mode & S_IWGRP) != 0) || 450b2546660SJohn Baldwin (ks->ks_mode & S_IWOTH) != 0 || suser(td) == 0) 451efaa6588SAlfred Perlstein return (0); 452efaa6588SAlfred Perlstein return (EPERM); 453efaa6588SAlfred Perlstein } 454efaa6588SAlfred Perlstein 455c3053131SPoul-Henning Kamp static void 456efaa6588SAlfred Perlstein sem_free(struct ksem *ks) 457efaa6588SAlfred Perlstein { 458efaa6588SAlfred Perlstein 459efaa6588SAlfred Perlstein nsems--; 460efaa6588SAlfred Perlstein if (ks->ks_onlist) 461efaa6588SAlfred Perlstein LIST_REMOVE(ks, ks_entry); 462efaa6588SAlfred Perlstein if (ks->ks_name != NULL) 463efaa6588SAlfred Perlstein free(ks->ks_name, M_SEM); 464efaa6588SAlfred Perlstein cv_destroy(&ks->ks_cv); 465efaa6588SAlfred Perlstein free(ks, M_SEM); 466efaa6588SAlfred Perlstein } 467efaa6588SAlfred Perlstein 468efaa6588SAlfred Perlstein static __inline struct kuser *sem_getuser(struct proc *p, struct ksem *ks); 469efaa6588SAlfred Perlstein 470efaa6588SAlfred Perlstein static __inline struct kuser * 471efaa6588SAlfred Perlstein sem_getuser(p, ks) 472efaa6588SAlfred Perlstein struct proc *p; 473efaa6588SAlfred Perlstein struct ksem *ks; 474efaa6588SAlfred Perlstein { 475efaa6588SAlfred Perlstein struct kuser *k; 476efaa6588SAlfred Perlstein 477efaa6588SAlfred Perlstein LIST_FOREACH(k, &ks->ks_users, ku_next) 478efaa6588SAlfred Perlstein if (k->ku_pid == p->p_pid) 479efaa6588SAlfred Perlstein return (k); 480efaa6588SAlfred Perlstein return (NULL); 481efaa6588SAlfred Perlstein } 482efaa6588SAlfred Perlstein 483c3053131SPoul-Henning Kamp static int 484b2546660SJohn Baldwin sem_hasopen(td, ks) 485b2546660SJohn Baldwin struct thread *td; 486efaa6588SAlfred Perlstein struct ksem *ks; 487efaa6588SAlfred Perlstein { 488efaa6588SAlfred Perlstein 489aae94fbbSDaniel Eischen return ((ks->ks_name == NULL && sem_perm(td, ks) == 0) 490b2546660SJohn Baldwin || sem_getuser(td->td_proc, ks) != NULL); 491efaa6588SAlfred Perlstein } 492efaa6588SAlfred Perlstein 493c3053131SPoul-Henning Kamp static int 494efaa6588SAlfred Perlstein sem_leave(p, ks) 495efaa6588SAlfred Perlstein struct proc *p; 496efaa6588SAlfred Perlstein struct ksem *ks; 497efaa6588SAlfred Perlstein { 498efaa6588SAlfred Perlstein struct kuser *k; 499efaa6588SAlfred Perlstein 500c814aa3fSAlfred Perlstein DP(("sem_leave: ks = %p\n", ks)); 501efaa6588SAlfred Perlstein k = sem_getuser(p, ks); 502c814aa3fSAlfred Perlstein DP(("sem_leave: ks = %p, k = %p\n", ks, k)); 503efaa6588SAlfred Perlstein if (k != NULL) { 504efaa6588SAlfred Perlstein LIST_REMOVE(k, ku_next); 505efaa6588SAlfred Perlstein sem_rel(ks); 506c814aa3fSAlfred Perlstein DP(("sem_leave: about to free k\n")); 507efaa6588SAlfred Perlstein free(k, M_SEM); 508c814aa3fSAlfred Perlstein DP(("sem_leave: returning\n")); 509efaa6588SAlfred Perlstein return (0); 510efaa6588SAlfred Perlstein } 511b3890a1cSAlfred Perlstein return (EINVAL); 512efaa6588SAlfred Perlstein } 513efaa6588SAlfred Perlstein 514c3053131SPoul-Henning Kamp static void 515efaa6588SAlfred Perlstein sem_enter(p, ks) 516efaa6588SAlfred Perlstein struct proc *p; 517efaa6588SAlfred Perlstein struct ksem *ks; 518efaa6588SAlfred Perlstein { 519efaa6588SAlfred Perlstein struct kuser *ku, *k; 520efaa6588SAlfred Perlstein 521a163d034SWarner Losh ku = malloc(sizeof(*ku), M_SEM, M_WAITOK); 522efaa6588SAlfred Perlstein ku->ku_pid = p->p_pid; 523efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 524efaa6588SAlfred Perlstein k = sem_getuser(p, ks); 525efaa6588SAlfred Perlstein if (k != NULL) { 526efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 527efaa6588SAlfred Perlstein free(ku, M_TEMP); 528efaa6588SAlfred Perlstein return; 529efaa6588SAlfred Perlstein } 530efaa6588SAlfred Perlstein LIST_INSERT_HEAD(&ks->ks_users, ku, ku_next); 531efaa6588SAlfred Perlstein sem_ref(ks); 532efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 533efaa6588SAlfred Perlstein } 534efaa6588SAlfred Perlstein 535efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 536efaa6588SAlfred Perlstein struct ksem_unlink_args { 537efaa6588SAlfred Perlstein char *name; 538efaa6588SAlfred Perlstein }; 539efaa6588SAlfred Perlstein int ksem_unlink(struct thread *td, struct ksem_unlink_args *uap); 540efaa6588SAlfred Perlstein #endif 541efaa6588SAlfred Perlstein 542efaa6588SAlfred Perlstein int 543efaa6588SAlfred Perlstein ksem_unlink(td, uap) 544efaa6588SAlfred Perlstein struct thread *td; 545efaa6588SAlfred Perlstein struct ksem_unlink_args *uap; 546efaa6588SAlfred Perlstein { 547efaa6588SAlfred Perlstein char name[SEM_MAX_NAMELEN + 1]; 548efaa6588SAlfred Perlstein size_t done; 549efaa6588SAlfred Perlstein int error; 550efaa6588SAlfred Perlstein 551efaa6588SAlfred Perlstein error = copyinstr(uap->name, name, SEM_MAX_NAMELEN + 1, &done); 552efaa6588SAlfred Perlstein return (error ? error : 553efaa6588SAlfred Perlstein kern_sem_unlink(td, name)); 554efaa6588SAlfred Perlstein } 555efaa6588SAlfred Perlstein 556efaa6588SAlfred Perlstein static int 557efaa6588SAlfred Perlstein kern_sem_unlink(td, name) 558efaa6588SAlfred Perlstein struct thread *td; 559efaa6588SAlfred Perlstein const char *name; 560efaa6588SAlfred Perlstein { 561efaa6588SAlfred Perlstein struct ksem *ks; 562efaa6588SAlfred Perlstein int error; 563efaa6588SAlfred Perlstein 564efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 565efaa6588SAlfred Perlstein ks = sem_lookup_byname(name); 566efaa6588SAlfred Perlstein if (ks == NULL) 567efaa6588SAlfred Perlstein error = ENOENT; 568efaa6588SAlfred Perlstein else 569b2546660SJohn Baldwin error = sem_perm(td, ks); 570c814aa3fSAlfred Perlstein DP(("sem_unlink: '%s' ks = %p, error = %d\n", name, ks, error)); 571efaa6588SAlfred Perlstein if (error == 0) { 572efaa6588SAlfred Perlstein LIST_REMOVE(ks, ks_entry); 573efaa6588SAlfred Perlstein LIST_INSERT_HEAD(&ksem_deadhead, ks, ks_entry); 574efaa6588SAlfred Perlstein sem_rel(ks); 575efaa6588SAlfred Perlstein } 576efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 577efaa6588SAlfred Perlstein return (error); 578efaa6588SAlfred Perlstein } 579efaa6588SAlfred Perlstein 580efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 581efaa6588SAlfred Perlstein struct ksem_close_args { 582efaa6588SAlfred Perlstein semid_t id; 583efaa6588SAlfred Perlstein }; 584efaa6588SAlfred Perlstein int ksem_close(struct thread *td, struct ksem_close_args *uap); 585efaa6588SAlfred Perlstein #endif 586efaa6588SAlfred Perlstein 587efaa6588SAlfred Perlstein int 588efaa6588SAlfred Perlstein ksem_close(struct thread *td, struct ksem_close_args *uap) 589efaa6588SAlfred Perlstein { 590efaa6588SAlfred Perlstein 591efaa6588SAlfred Perlstein return (kern_sem_close(td, uap->id)); 592efaa6588SAlfred Perlstein } 593efaa6588SAlfred Perlstein 594c3053131SPoul-Henning Kamp static int 595efaa6588SAlfred Perlstein kern_sem_close(td, id) 596efaa6588SAlfred Perlstein struct thread *td; 597efaa6588SAlfred Perlstein semid_t id; 598efaa6588SAlfred Perlstein { 599efaa6588SAlfred Perlstein struct ksem *ks; 600efaa6588SAlfred Perlstein int error; 601efaa6588SAlfred Perlstein 602efaa6588SAlfred Perlstein error = EINVAL; 603efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 604efaa6588SAlfred Perlstein ks = ID_TO_SEM(id); 605efaa6588SAlfred Perlstein /* this is not a valid operation for unnamed sems */ 606efaa6588SAlfred Perlstein if (ks != NULL && ks->ks_name != NULL) 607b3890a1cSAlfred Perlstein error = sem_leave(td->td_proc, ks); 608efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 609b3890a1cSAlfred Perlstein return (error); 610efaa6588SAlfred Perlstein } 611efaa6588SAlfred Perlstein 612efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 613efaa6588SAlfred Perlstein struct ksem_post_args { 614efaa6588SAlfred Perlstein semid_t id; 615efaa6588SAlfred Perlstein }; 616efaa6588SAlfred Perlstein int ksem_post(struct thread *td, struct ksem_post_args *uap); 617efaa6588SAlfred Perlstein #endif 618efaa6588SAlfred Perlstein int 619efaa6588SAlfred Perlstein ksem_post(td, uap) 620efaa6588SAlfred Perlstein struct thread *td; 621efaa6588SAlfred Perlstein struct ksem_post_args *uap; 622efaa6588SAlfred Perlstein { 623efaa6588SAlfred Perlstein 624efaa6588SAlfred Perlstein return (kern_sem_post(td, uap->id)); 625efaa6588SAlfred Perlstein } 626efaa6588SAlfred Perlstein 627c3053131SPoul-Henning Kamp static int 628efaa6588SAlfred Perlstein kern_sem_post(td, id) 629efaa6588SAlfred Perlstein struct thread *td; 630efaa6588SAlfred Perlstein semid_t id; 631efaa6588SAlfred Perlstein { 632efaa6588SAlfred Perlstein struct ksem *ks; 633efaa6588SAlfred Perlstein int error; 634efaa6588SAlfred Perlstein 635efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 636efaa6588SAlfred Perlstein ks = ID_TO_SEM(id); 637b2546660SJohn Baldwin if (ks == NULL || !sem_hasopen(td, ks)) { 638efaa6588SAlfred Perlstein error = EINVAL; 639efaa6588SAlfred Perlstein goto err; 640efaa6588SAlfred Perlstein } 641efaa6588SAlfred Perlstein if (ks->ks_value == SEM_VALUE_MAX) { 642efaa6588SAlfred Perlstein error = EOVERFLOW; 643efaa6588SAlfred Perlstein goto err; 644efaa6588SAlfred Perlstein } 645efaa6588SAlfred Perlstein ++ks->ks_value; 646efaa6588SAlfred Perlstein if (ks->ks_waiters > 0) 647efaa6588SAlfred Perlstein cv_signal(&ks->ks_cv); 648efaa6588SAlfred Perlstein error = 0; 649efaa6588SAlfred Perlstein err: 650efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 651efaa6588SAlfred Perlstein return (error); 652efaa6588SAlfred Perlstein } 653efaa6588SAlfred Perlstein 654efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 655efaa6588SAlfred Perlstein struct ksem_wait_args { 656efaa6588SAlfred Perlstein semid_t id; 657efaa6588SAlfred Perlstein }; 658efaa6588SAlfred Perlstein int ksem_wait(struct thread *td, struct ksem_wait_args *uap); 659efaa6588SAlfred Perlstein #endif 660efaa6588SAlfred Perlstein 661efaa6588SAlfred Perlstein int 662efaa6588SAlfred Perlstein ksem_wait(td, uap) 663efaa6588SAlfred Perlstein struct thread *td; 664efaa6588SAlfred Perlstein struct ksem_wait_args *uap; 665efaa6588SAlfred Perlstein { 666efaa6588SAlfred Perlstein 667aae94fbbSDaniel Eischen return (kern_sem_wait(td, uap->id, 0, NULL)); 668aae94fbbSDaniel Eischen } 669aae94fbbSDaniel Eischen 670aae94fbbSDaniel Eischen #ifndef _SYS_SYSPROTO_H_ 671aae94fbbSDaniel Eischen struct ksem_timedwait_args { 672aae94fbbSDaniel Eischen semid_t id; 673aae94fbbSDaniel Eischen struct timespec *abstime; 674aae94fbbSDaniel Eischen }; 675aae94fbbSDaniel Eischen int ksem_timedwait(struct thread *td, struct ksem_timedwait_args *uap); 676aae94fbbSDaniel Eischen #endif 677aae94fbbSDaniel Eischen int 678aae94fbbSDaniel Eischen ksem_timedwait(td, uap) 679aae94fbbSDaniel Eischen struct thread *td; 680aae94fbbSDaniel Eischen struct ksem_timedwait_args *uap; 681aae94fbbSDaniel Eischen { 682aae94fbbSDaniel Eischen struct timespec abstime; 683aae94fbbSDaniel Eischen struct timespec *ts; 684aae94fbbSDaniel Eischen int error; 685aae94fbbSDaniel Eischen 686aae94fbbSDaniel Eischen /* We allow a null timespec (wait forever). */ 687aae94fbbSDaniel Eischen if (uap->abstime == NULL) 688aae94fbbSDaniel Eischen ts = NULL; 689aae94fbbSDaniel Eischen else { 690aae94fbbSDaniel Eischen error = copyin(uap->abstime, &abstime, sizeof(abstime)); 691aae94fbbSDaniel Eischen if (error != 0) 692aae94fbbSDaniel Eischen return (error); 693aae94fbbSDaniel Eischen if (abstime.tv_nsec >= 1000000000 || abstime.tv_nsec < 0) 694aae94fbbSDaniel Eischen return (EINVAL); 695aae94fbbSDaniel Eischen ts = &abstime; 696aae94fbbSDaniel Eischen } 697aae94fbbSDaniel Eischen return (kern_sem_wait(td, uap->id, 0, ts)); 698efaa6588SAlfred Perlstein } 699efaa6588SAlfred Perlstein 700efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 701efaa6588SAlfred Perlstein struct ksem_trywait_args { 702efaa6588SAlfred Perlstein semid_t id; 703efaa6588SAlfred Perlstein }; 704efaa6588SAlfred Perlstein int ksem_trywait(struct thread *td, struct ksem_trywait_args *uap); 705efaa6588SAlfred Perlstein #endif 706efaa6588SAlfred Perlstein int 707efaa6588SAlfred Perlstein ksem_trywait(td, uap) 708efaa6588SAlfred Perlstein struct thread *td; 709efaa6588SAlfred Perlstein struct ksem_trywait_args *uap; 710efaa6588SAlfred Perlstein { 711efaa6588SAlfred Perlstein 712aae94fbbSDaniel Eischen return (kern_sem_wait(td, uap->id, 1, NULL)); 713efaa6588SAlfred Perlstein } 714efaa6588SAlfred Perlstein 715c3053131SPoul-Henning Kamp static int 716aae94fbbSDaniel Eischen kern_sem_wait(td, id, tryflag, abstime) 717efaa6588SAlfred Perlstein struct thread *td; 718efaa6588SAlfred Perlstein semid_t id; 719efaa6588SAlfred Perlstein int tryflag; 720aae94fbbSDaniel Eischen struct timespec *abstime; 721efaa6588SAlfred Perlstein { 722aae94fbbSDaniel Eischen struct timespec ts1, ts2; 723aae94fbbSDaniel Eischen struct timeval tv; 724efaa6588SAlfred Perlstein struct ksem *ks; 725efaa6588SAlfred Perlstein int error; 726efaa6588SAlfred Perlstein 727c814aa3fSAlfred Perlstein DP((">>> kern_sem_wait entered!\n")); 728efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 729efaa6588SAlfred Perlstein ks = ID_TO_SEM(id); 730efaa6588SAlfred Perlstein if (ks == NULL) { 731c814aa3fSAlfred Perlstein DP(("kern_sem_wait ks == NULL\n")); 732efaa6588SAlfred Perlstein error = EINVAL; 733efaa6588SAlfred Perlstein goto err; 734efaa6588SAlfred Perlstein } 735efaa6588SAlfred Perlstein sem_ref(ks); 736b2546660SJohn Baldwin if (!sem_hasopen(td, ks)) { 737c814aa3fSAlfred Perlstein DP(("kern_sem_wait hasopen failed\n")); 738efaa6588SAlfred Perlstein error = EINVAL; 739efaa6588SAlfred Perlstein goto err; 740efaa6588SAlfred Perlstein } 741c814aa3fSAlfred Perlstein DP(("kern_sem_wait value = %d, tryflag %d\n", ks->ks_value, tryflag)); 742efaa6588SAlfred Perlstein if (ks->ks_value == 0) { 743efaa6588SAlfred Perlstein ks->ks_waiters++; 744aae94fbbSDaniel Eischen if (tryflag != 0) 745aae94fbbSDaniel Eischen error = EAGAIN; 746aae94fbbSDaniel Eischen else if (abstime == NULL) 747aae94fbbSDaniel Eischen error = cv_wait_sig(&ks->ks_cv, &sem_lock); 748aae94fbbSDaniel Eischen else { 749aae94fbbSDaniel Eischen for (;;) { 750aae94fbbSDaniel Eischen ts1 = *abstime; 751aae94fbbSDaniel Eischen getnanotime(&ts2); 752aae94fbbSDaniel Eischen timespecsub(&ts1, &ts2); 753aae94fbbSDaniel Eischen TIMESPEC_TO_TIMEVAL(&tv, &ts1); 754aae94fbbSDaniel Eischen if (tv.tv_sec < 0) { 755aae94fbbSDaniel Eischen error = ETIMEDOUT; 756aae94fbbSDaniel Eischen break; 757aae94fbbSDaniel Eischen } 758aae94fbbSDaniel Eischen error = cv_timedwait_sig(&ks->ks_cv, 759aae94fbbSDaniel Eischen &sem_lock, tvtohz(&tv)); 760aae94fbbSDaniel Eischen if (error != EWOULDBLOCK) 761aae94fbbSDaniel Eischen break; 762aae94fbbSDaniel Eischen } 763aae94fbbSDaniel Eischen } 764efaa6588SAlfred Perlstein ks->ks_waiters--; 765efaa6588SAlfred Perlstein if (error) 766efaa6588SAlfred Perlstein goto err; 767efaa6588SAlfred Perlstein } 768efaa6588SAlfred Perlstein ks->ks_value--; 769efaa6588SAlfred Perlstein error = 0; 770efaa6588SAlfred Perlstein err: 771efaa6588SAlfred Perlstein if (ks != NULL) 772efaa6588SAlfred Perlstein sem_rel(ks); 773efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 774c814aa3fSAlfred Perlstein DP(("<<< kern_sem_wait leaving, error = %d\n", error)); 775efaa6588SAlfred Perlstein return (error); 776efaa6588SAlfred Perlstein } 777efaa6588SAlfred Perlstein 778efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 779efaa6588SAlfred Perlstein struct ksem_getvalue_args { 780efaa6588SAlfred Perlstein semid_t id; 781efaa6588SAlfred Perlstein int *val; 782efaa6588SAlfred Perlstein }; 783efaa6588SAlfred Perlstein int ksem_getvalue(struct thread *td, struct ksem_getvalue_args *uap); 784efaa6588SAlfred Perlstein #endif 785efaa6588SAlfred Perlstein int 786efaa6588SAlfred Perlstein ksem_getvalue(td, uap) 787efaa6588SAlfred Perlstein struct thread *td; 788efaa6588SAlfred Perlstein struct ksem_getvalue_args *uap; 789efaa6588SAlfred Perlstein { 790efaa6588SAlfred Perlstein struct ksem *ks; 791efaa6588SAlfred Perlstein int error, val; 792efaa6588SAlfred Perlstein 793efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 794efaa6588SAlfred Perlstein ks = ID_TO_SEM(uap->id); 795b2546660SJohn Baldwin if (ks == NULL || !sem_hasopen(td, ks)) { 796efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 797efaa6588SAlfred Perlstein return (EINVAL); 798efaa6588SAlfred Perlstein } 799efaa6588SAlfred Perlstein val = ks->ks_value; 800efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 801efaa6588SAlfred Perlstein error = copyout(&val, uap->val, sizeof(val)); 802efaa6588SAlfred Perlstein return (error); 803efaa6588SAlfred Perlstein } 804efaa6588SAlfred Perlstein 805efaa6588SAlfred Perlstein #ifndef _SYS_SYSPROTO_H_ 806efaa6588SAlfred Perlstein struct ksem_destroy_args { 807efaa6588SAlfred Perlstein semid_t id; 808efaa6588SAlfred Perlstein }; 809efaa6588SAlfred Perlstein int ksem_destroy(struct thread *td, struct ksem_destroy_args *uap); 810efaa6588SAlfred Perlstein #endif 811efaa6588SAlfred Perlstein int 812efaa6588SAlfred Perlstein ksem_destroy(td, uap) 813efaa6588SAlfred Perlstein struct thread *td; 814efaa6588SAlfred Perlstein struct ksem_destroy_args *uap; 815efaa6588SAlfred Perlstein { 816efaa6588SAlfred Perlstein struct ksem *ks; 817efaa6588SAlfred Perlstein int error; 818efaa6588SAlfred Perlstein 819efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 820efaa6588SAlfred Perlstein ks = ID_TO_SEM(uap->id); 821b2546660SJohn Baldwin if (ks == NULL || !sem_hasopen(td, ks) || 822efaa6588SAlfred Perlstein ks->ks_name != NULL) { 823efaa6588SAlfred Perlstein error = EINVAL; 824efaa6588SAlfred Perlstein goto err; 825efaa6588SAlfred Perlstein } 826efaa6588SAlfred Perlstein if (ks->ks_waiters != 0) { 827efaa6588SAlfred Perlstein error = EBUSY; 828efaa6588SAlfred Perlstein goto err; 829efaa6588SAlfred Perlstein } 830efaa6588SAlfred Perlstein sem_rel(ks); 831efaa6588SAlfred Perlstein error = 0; 832efaa6588SAlfred Perlstein err: 833efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 834efaa6588SAlfred Perlstein return (error); 835efaa6588SAlfred Perlstein } 836efaa6588SAlfred Perlstein 837590f242cSRobert Watson /* 838590f242cSRobert Watson * Count the number of kusers associated with a proc, so as to guess at how 839590f242cSRobert Watson * many to allocate when forking. 840590f242cSRobert Watson */ 841590f242cSRobert Watson static int 842590f242cSRobert Watson sem_count_proc(p) 843590f242cSRobert Watson struct proc *p; 844590f242cSRobert Watson { 845590f242cSRobert Watson struct ksem *ks; 846590f242cSRobert Watson struct kuser *ku; 847590f242cSRobert Watson int count; 848590f242cSRobert Watson 849590f242cSRobert Watson mtx_assert(&sem_lock, MA_OWNED); 850590f242cSRobert Watson 851590f242cSRobert Watson count = 0; 852590f242cSRobert Watson LIST_FOREACH(ks, &ksem_head, ks_entry) { 853590f242cSRobert Watson LIST_FOREACH(ku, &ks->ks_users, ku_next) { 854590f242cSRobert Watson if (ku->ku_pid == p->p_pid) 855590f242cSRobert Watson count++; 856590f242cSRobert Watson } 857590f242cSRobert Watson } 858590f242cSRobert Watson LIST_FOREACH(ks, &ksem_deadhead, ks_entry) { 859590f242cSRobert Watson LIST_FOREACH(ku, &ks->ks_users, ku_next) { 860590f242cSRobert Watson if (ku->ku_pid == p->p_pid) 861590f242cSRobert Watson count++; 862590f242cSRobert Watson } 863590f242cSRobert Watson } 864590f242cSRobert Watson return (count); 865590f242cSRobert Watson } 866590f242cSRobert Watson 867590f242cSRobert Watson /* 868590f242cSRobert Watson * When a process forks, the child process must gain a reference to each open 869590f242cSRobert Watson * semaphore in the parent process, whether it is unlinked or not. This 870590f242cSRobert Watson * requires allocating a kuser structure for each semaphore reference in the 871590f242cSRobert Watson * new process. Because the set of semaphores in the parent can change while 872590f242cSRobert Watson * the fork is in progress, we have to handle races -- first we attempt to 873590f242cSRobert Watson * allocate enough storage to acquire references to each of the semaphores, 874590f242cSRobert Watson * then we enter the semaphores and release the temporary references. 875590f242cSRobert Watson */ 876590f242cSRobert Watson static void 877590f242cSRobert Watson sem_forkhook(arg, p1, p2, flags) 878590f242cSRobert Watson void *arg; 879590f242cSRobert Watson struct proc *p1; 880590f242cSRobert Watson struct proc *p2; 881590f242cSRobert Watson int flags; 882590f242cSRobert Watson { 883590f242cSRobert Watson struct ksem *ks, **sem_array; 884590f242cSRobert Watson int count, i, new_count; 885590f242cSRobert Watson struct kuser *ku; 886590f242cSRobert Watson 887590f242cSRobert Watson mtx_lock(&sem_lock); 888590f242cSRobert Watson count = sem_count_proc(p1); 889590f242cSRobert Watson race_lost: 890590f242cSRobert Watson mtx_assert(&sem_lock, MA_OWNED); 891590f242cSRobert Watson mtx_unlock(&sem_lock); 892590f242cSRobert Watson sem_array = malloc(sizeof(struct ksem *) * count, M_TEMP, M_WAITOK); 893590f242cSRobert Watson mtx_lock(&sem_lock); 894590f242cSRobert Watson new_count = sem_count_proc(p1); 895590f242cSRobert Watson if (count < new_count) { 896590f242cSRobert Watson /* Lost race, repeat and allocate more storage. */ 897590f242cSRobert Watson free(sem_array, M_TEMP); 898590f242cSRobert Watson count = new_count; 899590f242cSRobert Watson goto race_lost; 900590f242cSRobert Watson } 901590f242cSRobert Watson /* 902590f242cSRobert Watson * Given an array capable of storing an adequate number of semaphore 903590f242cSRobert Watson * references, now walk the list of semaphores and acquire a new 904590f242cSRobert Watson * reference for any semaphore opened by p1. 905590f242cSRobert Watson */ 906590f242cSRobert Watson count = new_count; 907590f242cSRobert Watson i = 0; 908590f242cSRobert Watson LIST_FOREACH(ks, &ksem_head, ks_entry) { 909590f242cSRobert Watson LIST_FOREACH(ku, &ks->ks_users, ku_next) { 910590f242cSRobert Watson if (ku->ku_pid == p1->p_pid) { 911590f242cSRobert Watson sem_ref(ks); 912590f242cSRobert Watson sem_array[i] = ks; 913590f242cSRobert Watson break; 914590f242cSRobert Watson } 915590f242cSRobert Watson } 916590f242cSRobert Watson } 917590f242cSRobert Watson LIST_FOREACH(ks, &ksem_deadhead, ks_entry) { 918590f242cSRobert Watson LIST_FOREACH(ku, &ks->ks_users, ku_next) { 919590f242cSRobert Watson if (ku->ku_pid == p1->p_pid) { 920590f242cSRobert Watson sem_ref(ks); 921590f242cSRobert Watson sem_array[i] = ks; 922590f242cSRobert Watson break; 923590f242cSRobert Watson } 924590f242cSRobert Watson } 925590f242cSRobert Watson } 926590f242cSRobert Watson mtx_unlock(&sem_lock); 927590f242cSRobert Watson KASSERT(i + 1 == count, ("sem_forkhook: i != count (%d, %d)", i, 928590f242cSRobert Watson count)); 929590f242cSRobert Watson /* 930590f242cSRobert Watson * Now cause p2 to enter each of the referenced semaphores, then 931590f242cSRobert Watson * release our temporary reference. This is pretty inefficient. 932590f242cSRobert Watson * Finally, free our temporary array. 933590f242cSRobert Watson */ 934590f242cSRobert Watson for (i = 0; i < count; i++) { 935590f242cSRobert Watson sem_enter(p2, sem_array[i]); 936590f242cSRobert Watson mtx_lock(&sem_lock); 937590f242cSRobert Watson sem_rel(sem_array[i]); 938590f242cSRobert Watson mtx_unlock(&sem_lock); 939590f242cSRobert Watson } 940590f242cSRobert Watson free(sem_array, M_TEMP); 941590f242cSRobert Watson } 942590f242cSRobert Watson 943c3053131SPoul-Henning Kamp static void 94475b8b3b2SJohn Baldwin sem_exithook(arg, p) 94575b8b3b2SJohn Baldwin void *arg; 946efaa6588SAlfred Perlstein struct proc *p; 947efaa6588SAlfred Perlstein { 948efaa6588SAlfred Perlstein struct ksem *ks, *ksnext; 949efaa6588SAlfred Perlstein 950efaa6588SAlfred Perlstein mtx_lock(&sem_lock); 951efaa6588SAlfred Perlstein ks = LIST_FIRST(&ksem_head); 952efaa6588SAlfred Perlstein while (ks != NULL) { 953efaa6588SAlfred Perlstein ksnext = LIST_NEXT(ks, ks_entry); 954efaa6588SAlfred Perlstein sem_leave(p, ks); 955efaa6588SAlfred Perlstein ks = ksnext; 956efaa6588SAlfred Perlstein } 957efaa6588SAlfred Perlstein ks = LIST_FIRST(&ksem_deadhead); 958efaa6588SAlfred Perlstein while (ks != NULL) { 959efaa6588SAlfred Perlstein ksnext = LIST_NEXT(ks, ks_entry); 960efaa6588SAlfred Perlstein sem_leave(p, ks); 961efaa6588SAlfred Perlstein ks = ksnext; 962efaa6588SAlfred Perlstein } 963efaa6588SAlfred Perlstein mtx_unlock(&sem_lock); 964efaa6588SAlfred Perlstein } 965efaa6588SAlfred Perlstein 966efaa6588SAlfred Perlstein static int 967efaa6588SAlfred Perlstein sem_modload(struct module *module, int cmd, void *arg) 968efaa6588SAlfred Perlstein { 969efaa6588SAlfred Perlstein int error = 0; 970efaa6588SAlfred Perlstein 971efaa6588SAlfred Perlstein switch (cmd) { 972efaa6588SAlfred Perlstein case MOD_LOAD: 973efaa6588SAlfred Perlstein mtx_init(&sem_lock, "sem", "semaphore", MTX_DEF); 974efaa6588SAlfred Perlstein p31b_setcfg(CTL_P1003_1B_SEM_NSEMS_MAX, SEM_MAX); 975efaa6588SAlfred Perlstein p31b_setcfg(CTL_P1003_1B_SEM_VALUE_MAX, SEM_VALUE_MAX); 97675b8b3b2SJohn Baldwin sem_exit_tag = EVENTHANDLER_REGISTER(process_exit, sem_exithook, 97775b8b3b2SJohn Baldwin NULL, EVENTHANDLER_PRI_ANY); 97875b8b3b2SJohn Baldwin sem_exec_tag = EVENTHANDLER_REGISTER(process_exec, sem_exithook, 97975b8b3b2SJohn Baldwin NULL, EVENTHANDLER_PRI_ANY); 980590f242cSRobert Watson sem_fork_tag = EVENTHANDLER_REGISTER(process_fork, sem_forkhook, NULL, EVENTHANDLER_PRI_ANY); 981efaa6588SAlfred Perlstein break; 982efaa6588SAlfred Perlstein case MOD_UNLOAD: 983efaa6588SAlfred Perlstein if (nsems != 0) { 984efaa6588SAlfred Perlstein error = EOPNOTSUPP; 985efaa6588SAlfred Perlstein break; 986efaa6588SAlfred Perlstein } 98775b8b3b2SJohn Baldwin EVENTHANDLER_DEREGISTER(process_exit, sem_exit_tag); 98875b8b3b2SJohn Baldwin EVENTHANDLER_DEREGISTER(process_exec, sem_exec_tag); 989590f242cSRobert Watson EVENTHANDLER_DEREGISTER(process_fork, sem_fork_tag); 990efaa6588SAlfred Perlstein mtx_destroy(&sem_lock); 991efaa6588SAlfred Perlstein break; 992efaa6588SAlfred Perlstein case MOD_SHUTDOWN: 993efaa6588SAlfred Perlstein break; 994efaa6588SAlfred Perlstein default: 995efaa6588SAlfred Perlstein error = EINVAL; 996efaa6588SAlfred Perlstein break; 997efaa6588SAlfred Perlstein } 998efaa6588SAlfred Perlstein return (error); 999efaa6588SAlfred Perlstein } 1000efaa6588SAlfred Perlstein 1001efaa6588SAlfred Perlstein static moduledata_t sem_mod = { 1002efaa6588SAlfred Perlstein "sem", 1003efaa6588SAlfred Perlstein &sem_modload, 1004efaa6588SAlfred Perlstein NULL 1005efaa6588SAlfred Perlstein }; 1006efaa6588SAlfred Perlstein 1007efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_init); 1008efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_open); 1009efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_unlink); 1010efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_close); 1011efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_post); 1012efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_wait); 1013aae94fbbSDaniel Eischen SYSCALL_MODULE_HELPER(ksem_timedwait); 1014efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_trywait); 1015efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_getvalue); 1016efaa6588SAlfred Perlstein SYSCALL_MODULE_HELPER(ksem_destroy); 1017efaa6588SAlfred Perlstein 1018efaa6588SAlfred Perlstein DECLARE_MODULE(sem, sem_mod, SI_SUB_SYSV_SEM, SI_ORDER_FIRST); 1019efaa6588SAlfred Perlstein MODULE_VERSION(sem, 1); 1020