diff options
Diffstat (limited to 'winsup/cygserver/sysv_sem.cc')
| -rw-r--r-- | winsup/cygserver/sysv_sem.cc | 1324 |
1 files changed, 0 insertions, 1324 deletions
diff --git a/winsup/cygserver/sysv_sem.cc b/winsup/cygserver/sysv_sem.cc deleted file mode 100644 index ccb7a1246..000000000 --- a/winsup/cygserver/sysv_sem.cc +++ /dev/null @@ -1,1324 +0,0 @@ -/* - * Implementation of SVID semaphores - * - * Author: Daniel Boulet - * - * This software is provided ``AS IS'' without any warranties of any kind. - */ - -/* - * This file is heavily changed to become part of Cygwin's cygserver. - */ - -#ifdef __OUTSIDE_CYGWIN__ -#include "woutsup.h" -#include <sys/cygwin.h> -#include <sys/cdefs.h> -#ifndef __FBSDID -#define __FBSDID(s) const char version[] = (s) -#endif -__FBSDID("$FreeBSD: /usr/local/www/cvsroot/FreeBSD/src/sys/kern/sysv_sem.c,v 1.67 2003/11/15 11:56:53 tjr Exp $"); - -#define _KERNEL 1 -#define __BSD_VISIBLE 1 -#include <sys/types.h> -#include <sys/ipc.h> - -#include <sys/param.h> -#include <sys/sysproto.h> -#include <sys/lock.h> -#include <sys/sem.h> -#include <sys/queue.h> -#include <malloc.h> -#include <errno.h> -#include <time.h> -#include "cygserver.h" -#include "process.h" -#include "cygserver_ipc.h" - -#ifdef __CYGWIN__ -#define __semctl semctl -#define __semctl_args semctl_args -#define SEM_DEBUG -#endif /* __CYGWIN__ */ - -#ifdef SEM_DEBUG -#define DPRINTF(a) debug_printf a -#else -#define DPRINTF(a) -#endif - -static int semvalid(int semid, struct semid_ds *semaptr); - -static struct sem_undo *semu_alloc(struct thread *td); -static int semundo_adjust(struct thread *td, struct sem_undo **supptr, - int semid, int semnum, int adjval); -static void semundo_clear(int semid, int semnum); - -#ifndef _SYS_SYSPROTO_H_ -struct __semctl_args; -int __semctl(struct thread *td, struct __semctl_args *uap); -struct semget_args; -int semget(struct thread *td, struct semget_args *uap); -struct semop_args; -int semop(struct thread *td, struct semop_args *uap); -#endif - -#ifndef __CYGWIN__ -/* XXX casting to (sy_call_t *) is bogus, as usual. */ -static sy_call_t *semcalls[] = { - (sy_call_t *)__semctl, (sy_call_t *)semget, - (sy_call_t *)semop -}; -#endif - -static struct mtx sem_mtx; /* semaphore global lock */ -static int semtots = 0; -static int semtot = 0; -static struct semid_ds *sema; /* semaphore id pool */ -static struct mtx *sema_mtx; /* semaphore id pool mutexes*/ -static struct sem *sem; /* semaphore pool */ -SLIST_HEAD(, sem_undo) semu_list; /* list of active undo structures */ -static int *semu; /* undo structure pool */ -#ifndef __CYGWIN__ -static eventhandler_tag semexit_tag; -#endif /* __CYGWIN__ */ - -#define SEMUNDO_MTX sem_mtx -#define SEMUNDO_LOCK() mtx_lock(&SEMUNDO_MTX); -#define SEMUNDO_HOOKLOCK() _mtx_lock(&SEMUNDO_MTX, p->winpid, __FILE__, __LINE__); -#define SEMUNDO_UNLOCK() mtx_unlock(&SEMUNDO_MTX); -#define SEMUNDO_LOCKASSERT(how) mtx_assert(&SEMUNDO_MTX, (how)); - -struct sem { - u_short semval; /* semaphore value */ - pid_t sempid; /* pid of last operation */ - u_short semncnt; /* # awaiting semval > cval */ - u_short semzcnt; /* # awaiting semval = 0 */ -}; - -/* - * Undo structure (one per process) - */ -struct undo { - short un_adjval; /* adjust on exit values */ - short un_num; /* semaphore # */ - int un_id; /* semid */ -} un_ent[1]; /* undo entries */ - -struct sem_undo { - SLIST_ENTRY(sem_undo) un_next; /* ptr to next active undo structure */ - struct proc *un_proc; /* owner of this structure */ - short un_cnt; /* # of active entries */ - struct undo un_ent[1]; /* undo entries */ -}; - -/* - * Configuration parameters - */ -#ifndef SEMMNI -#define SEMMNI 10 /* # of semaphore identifiers */ -#endif -#ifndef SEMMNS -#define SEMMNS 60 /* # of semaphores in system */ -#endif -#ifndef SEMUME -#define SEMUME 10 /* max # of undo entries per process */ -#endif -#ifndef SEMMNU -#define SEMMNU 30 /* # of undo structures in system */ -#endif - -/* shouldn't need tuning */ -#ifndef SEMMAP -#define SEMMAP 30 /* # of entries in semaphore map */ -#endif -#ifndef SEMMSL -#define SEMMSL SEMMNS /* max # of semaphores per id */ -#endif -#ifndef SEMOPM -#define SEMOPM 100 /* max # of operations per semop call */ -#endif - -#ifndef SEMVMX -#define SEMVMX 32767 /* semaphore maximum value */ -#endif -#ifndef SEMAEM -#define SEMAEM 16384 /* adjust on exit max value */ -#endif - -/* - * Due to the way semaphore memory is allocated, we have to ensure that - * SEMUSZ is properly aligned. - */ - -#define SEM_ALIGN(bytes) (((bytes) + (sizeof(long) - 1)) & ~(sizeof(long) - 1)) - -/* actual size of an undo structure */ -#define SEMUSZ SEM_ALIGN(offsetof(struct sem_undo, un_ent[SEMUME])) - -/* - * Macro to find a particular sem_undo vector - */ -#define SEMU(ix) \ - ((struct sem_undo *)(((intptr_t)semu)+ix * seminfo.semusz)) - -/* - * semaphore info struct - */ -struct seminfo seminfo = { - SEMMNI, /* # of semaphore identifiers */ - SEMMNS, /* # of semaphores in system */ - SEMMSL, /* max # of semaphores per id */ - SEMOPM, /* max # of operations per semop call */ - SEMMNU, /* # of undo structures in system */ - SEMUME, /* max # of undo entries per process */ - SEMVMX, /* semaphore maximum value */ - SEMAEM, /* adjust on exit max value */ - SEMMAP, /* # of entries in semaphore map */ - SEMUSZ /* size in bytes of undo structure */ -}; - -#ifndef __CYGWIN__ -SYSCTL_DECL(_kern_ipc); -SYSCTL_INT(_kern_ipc, OID_AUTO, semmap, CTLFLAG_RW, &seminfo.semmap, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semmni, CTLFLAG_RDTUN, &seminfo.semmni, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semmns, CTLFLAG_RDTUN, &seminfo.semmns, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semmnu, CTLFLAG_RDTUN, &seminfo.semmnu, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semmsl, CTLFLAG_RW, &seminfo.semmsl, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semopm, CTLFLAG_RDTUN, &seminfo.semopm, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semume, CTLFLAG_RDTUN, &seminfo.semume, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semusz, CTLFLAG_RDTUN, &seminfo.semusz, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semvmx, CTLFLAG_RW, &seminfo.semvmx, 0, ""); -SYSCTL_INT(_kern_ipc, OID_AUTO, semaem, CTLFLAG_RW, &seminfo.semaem, 0, ""); -SYSCTL_PROC(_kern_ipc, OID_AUTO, sema, CTLFLAG_RD, - NULL, 0, sysctl_sema, "", ""); -#endif /* __CYGWIN__ */ - -void -seminit(void) -{ - int i; - - TUNABLE_INT_FETCH("kern.ipc.semmap", &seminfo.semmap); - TUNABLE_INT_FETCH("kern.ipc.semmni", &seminfo.semmni); - TUNABLE_INT_FETCH("kern.ipc.semmns", &seminfo.semmns); - TUNABLE_INT_FETCH("kern.ipc.semmnu", &seminfo.semmnu); - TUNABLE_INT_FETCH("kern.ipc.semmsl", &seminfo.semmsl); - TUNABLE_INT_FETCH("kern.ipc.semopm", &seminfo.semopm); - TUNABLE_INT_FETCH("kern.ipc.semume", &seminfo.semume); - TUNABLE_INT_FETCH("kern.ipc.semusz", &seminfo.semusz); - TUNABLE_INT_FETCH("kern.ipc.semvmx", &seminfo.semvmx); - TUNABLE_INT_FETCH("kern.ipc.semaem", &seminfo.semaem); - -#ifdef __CYGWIN__ - /* It's too dangerous a setting to leave it alone. - Keep that clean here. */ - seminfo.semusz = SEM_ALIGN(offsetof(struct sem_undo, - un_ent[seminfo.semume])); -#endif /* __CYGWIN__ */ - - sem = (struct sem *) sys_malloc(sizeof(struct sem) * seminfo.semmns, M_SEM, M_WAITOK); - sema = (struct semid_ds *) sys_malloc(sizeof(struct semid_ds) * seminfo.semmni, M_SEM, - M_WAITOK); - sema_mtx = (struct mtx *) sys_malloc(sizeof(struct mtx) * seminfo.semmni, M_SEM, - M_WAITOK | M_ZERO); - semu = (int *) sys_malloc(seminfo.semmnu * seminfo.semusz, M_SEM, M_WAITOK); - - for (i = 0; i < seminfo.semmni; i++) { - sema[i].sem_base = 0; - sema[i].sem_perm.mode = 0; - sema[i].sem_perm.seq = 0; - } - for (i = 0; i < seminfo.semmni; i++) - mtx_init(&sema_mtx[i], "semid", NULL, MTX_DEF); - for (i = 0; i < seminfo.semmnu; i++) { - struct sem_undo *suptr = SEMU(i); - suptr->un_proc = NULL; - } - SLIST_INIT(&semu_list); - mtx_init(&sem_mtx, "sem", NULL, MTX_DEF); -#ifndef __CYGWIN__ - semexit_tag = EVENTHANDLER_REGISTER(process_exit, semexit_myhook, NULL, - EVENTHANDLER_PRI_ANY); -#endif /* __CYGWIN__ */ -} - -int -semunload(void) -{ -#ifndef __CYGWIN__ /* Would result in being unable to shutdown the - server gracefully. */ - if (semtot != 0) - return (EBUSY); - - EVENTHANDLER_DEREGISTER(process_exit, semexit_tag); -#endif /* __CYGWIN__ */ - sys_free(sem, M_SEM); - sys_free(sema, M_SEM); - sys_free(semu, M_SEM); - for (int i = 0; i < seminfo.semmni; i++) - mtx_destroy(&sema_mtx[i]); - mtx_destroy(&sem_mtx); - return (0); -} - -#ifndef __CYGWIN__ -static int -sysvsem_modload(struct module *module, int cmd, void *arg) -{ - int error = 0; - - switch (cmd) { - case MOD_LOAD: - seminit(); - break; - case MOD_UNLOAD: - error = semunload(); - break; - case MOD_SHUTDOWN: - break; - default: - error = EINVAL; - break; - } - return (error); -} - -static moduledata_t sysvsem_mod = { - "sysvsem", - &sysvsem_modload, - NULL -}; - -SYSCALL_MODULE_HELPER(semsys); -SYSCALL_MODULE_HELPER(__semctl); -SYSCALL_MODULE_HELPER(semget); -SYSCALL_MODULE_HELPER(semop); - -DECLARE_MODULE(sysvsem, sysvsem_mod, - SI_SUB_SYSV_SEM, SI_ORDER_FIRST); -MODULE_VERSION(sysvsem, 1); - -/* - * Entry point for all SEM calls - * - * MPSAFE - */ -int -semsys(td, uap) - struct thread *td; - /* XXX actually varargs. */ - struct semsys_args /* { - int which; - int a2; - int a3; - int a4; - int a5; - } */ *uap; -{ - int error; - - if (!jail_sysvipc_allowed && jailed(td->td_ucred)) - return (ENOSYS); - if (uap->which < 0 || - uap->which >= sizeof(semcalls)/sizeof(semcalls[0])) - return (EINVAL); - error = (*semcalls[uap->which])(td, &uap->a2); - return (error); -} -#endif /* __CYGWIN__ */ - -/* - * Allocate a new sem_undo structure for a process - * (returns ptr to structure or NULL if no more room) - */ - -static struct sem_undo * -semu_alloc(struct thread *td) -{ - int i; - struct sem_undo *suptr; - struct sem_undo **supptr; - int attempt; - - SEMUNDO_LOCKASSERT(MA_OWNED); - /* - * Try twice to allocate something. - * (we'll purge an empty structure after the first pass so - * two passes are always enough) - */ - - for (attempt = 0; attempt < 2; attempt++) { - /* - * Look for a free structure. - * Fill it in and return it if we find one. - */ - - for (i = 0; i < seminfo.semmnu; i++) { - suptr = SEMU(i); - if (suptr->un_proc == NULL) { - SLIST_INSERT_HEAD(&semu_list, suptr, un_next); - suptr->un_cnt = 0; - suptr->un_proc = td->td_proc; - return(suptr); - } - } - - /* - * We didn't find a free one, if this is the first attempt - * then try to free a structure. - */ - - if (attempt == 0) { - /* All the structures are in use - try to free one */ - int did_something = 0; - - SLIST_FOREACH_PREVPTR(suptr, supptr, &semu_list, - un_next) { - if (suptr->un_cnt == 0) { - suptr->un_proc = NULL; - did_something = 1; - *supptr = SLIST_NEXT(suptr, un_next); - break; - } - } - - /* If we didn't free anything then just give-up */ - if (!did_something) - return(NULL); - } else { - /* - * The second pass failed even though we freed - * something after the first pass! - * This is IMPOSSIBLE! - */ - panic("semu_alloc - second attempt failed"); - } - } - return (NULL); -} - -/* - * Adjust a particular entry for a particular proc - */ - -static int -semundo_adjust(struct thread *td, struct sem_undo **supptr, int semid, - int semnum, int adjval) -{ - struct proc *p = td->td_proc; - struct sem_undo *suptr; - struct undo *sunptr; - int i; - - SEMUNDO_LOCKASSERT(MA_OWNED); - /* Look for and remember the sem_undo if the caller doesn't provide - it */ - - suptr = *supptr; - if (suptr == NULL) { - SLIST_FOREACH(suptr, &semu_list, un_next) { - if (suptr->un_proc == p) { - *supptr = suptr; - break; - } - } - if (suptr == NULL) { - if (adjval == 0) - return(0); - suptr = semu_alloc(td); - if (suptr == NULL) - return(ENOSPC); - *supptr = suptr; - } - } - - /* - * Look for the requested entry and adjust it (delete if adjval becomes - * 0). - */ - sunptr = &suptr->un_ent[0]; - for (i = 0; i < suptr->un_cnt; i++, sunptr++) { - if (sunptr->un_id != semid || sunptr->un_num != semnum) - continue; - if (adjval != 0) { - adjval += sunptr->un_adjval; - if (adjval > seminfo.semaem || adjval < -seminfo.semaem) - return (ERANGE); - } - sunptr->un_adjval = adjval; - if (sunptr->un_adjval == 0) { - suptr->un_cnt--; - if (i < suptr->un_cnt) - suptr->un_ent[i] = - suptr->un_ent[suptr->un_cnt]; - } - return(0); - } - - /* Didn't find the right entry - create it */ - if (adjval == 0) - return(0); - if (adjval > seminfo.semaem || adjval < -seminfo.semaem) - return (ERANGE); - if (suptr->un_cnt != seminfo.semume) { - sunptr = &suptr->un_ent[suptr->un_cnt]; - suptr->un_cnt++; - sunptr->un_adjval = adjval; - sunptr->un_id = semid; sunptr->un_num = semnum; - } else - return(EINVAL); - return(0); -} - -static void -semundo_clear(int semid, int semnum) -{ - struct sem_undo *suptr; - - SEMUNDO_LOCKASSERT(MA_OWNED); - SLIST_FOREACH(suptr, &semu_list, un_next) { - struct undo *sunptr = &suptr->un_ent[0]; - int i = 0; - - while (i < suptr->un_cnt) { - if (sunptr->un_id == semid) { - if (semnum == -1 || sunptr->un_num == semnum) { - suptr->un_cnt--; - if (i < suptr->un_cnt) { - suptr->un_ent[i] = - suptr->un_ent[suptr->un_cnt]; - continue; - } - } - if (semnum != -1) - break; - } - i++, sunptr++; - } - } -} - -static int -semvalid(int semid, struct semid_ds *semaptr) -{ - - return ((semaptr->sem_perm.mode & SEM_ALLOC) == 0 || - semaptr->sem_perm.seq != IPCID_TO_SEQ(semid) ? EINVAL : 0); -} - -/* - * Note that the user-mode half of this passes a union, not a pointer - */ -#ifndef _SYS_SYSPROTO_H_ -struct __semctl_args { - int semid; - int semnum; - int cmd; - union semun *arg; -}; -#endif - -/* - * MPSAFE - */ -int -__semctl(struct thread *td, struct __semctl_args *uap) -{ - int semid = uap->semid; - int semnum = uap->semnum; - int cmd = uap->cmd; - u_short *array; - union semun *arg = uap->arg; - union semun real_arg; -#ifndef __CYGWIN__ - struct ucred *cred = td->td_ucred; -#endif - int i, rval, error; - struct semid_ds sbuf; - struct semid_ds *semaptr; - struct mtx *sema_mtxp; - u_short usval, count; - - DPRINTF(("call to semctl(%d, %d, %d, 0x%x)\n", - semid, semnum, cmd, arg)); - if (!jail_sysvipc_allowed && jailed(td->td_ucred)) - return (ENOSYS); - - array = NULL; - - switch(cmd) { -#ifdef __CYGWIN__ - case IPC_INFO: - if ((error = copyin(arg, &real_arg, sizeof(real_arg))) != 0) - return (error); - if (!semid) { - error = copyout(&seminfo, real_arg.buf, - sizeof(struct seminfo)); - td->td_retval[0] = error ? -1 : 0; - return (error); - } - if (semid > seminfo.semmni) - semid = seminfo.semmni; - error = copyout(sema, real_arg.buf, - semid * sizeof(struct semid_ds)); - td->td_retval[0] = error ? -1 : 0; - return (error); - case SEM_INFO: - if (!(error = copyin(arg, &real_arg, sizeof(real_arg)))) { - struct sem_info sem_info; - sem_info.sem_ids = semtots; - sem_info.sem_num = semtot; - error = copyout(&sem_info, real_arg.buf, - sizeof(struct sem_info)); - } - td->td_retval[0] = error ? -1 : 0; - return (error); - -#endif /* __CYGWIN__ */ - case SEM_STAT: - if (semid < 0 || semid >= seminfo.semmni) - return (EINVAL); - if ((error = copyin(arg, &real_arg, sizeof(real_arg))) != 0) - return (error); - semaptr = &sema[semid]; - sema_mtxp = &sema_mtx[semid]; - mtx_lock(sema_mtxp); - if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0) { - error = EINVAL; - goto done2; - } - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_R))) - goto done2; - mtx_unlock(sema_mtxp); - error = copyout(semaptr, real_arg.buf, sizeof(struct semid_ds)); - rval = IXSEQ_TO_IPCID(semid,semaptr->sem_perm); - if (error == 0) - td->td_retval[0] = rval; - return (error); - } - - semid = IPCID_TO_IX(semid); - if (semid < 0 || semid >= seminfo.semmni) - return (EINVAL); - - semaptr = &sema[semid]; - sema_mtxp = &sema_mtx[semid]; - - error = 0; - rval = 0; - - switch (cmd) { - case IPC_RMID: - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_M))) - goto done2; -#ifdef __CYGWIN__ - semaptr->sem_perm.cuid = td->ipcblk->uid; - semaptr->sem_perm.uid = td->ipcblk->uid; -#else - semaptr->sem_perm.cuid = cred->cr_uid; - semaptr->sem_perm.uid = cred->cr_uid; -#endif - semtot -= semaptr->sem_nsems; - semtots--; - for (i = semaptr->sem_base - sem; i < semtot; i++) - sem[i] = sem[i + semaptr->sem_nsems]; - for (i = 0; i < seminfo.semmni; i++) { - if ((sema[i].sem_perm.mode & SEM_ALLOC) && - sema[i].sem_base > semaptr->sem_base) - sema[i].sem_base -= semaptr->sem_nsems; - } - semaptr->sem_perm.mode = 0; - SEMUNDO_LOCK(); - semundo_clear(semid, -1); - SEMUNDO_UNLOCK(); - wakeup(semaptr); - break; - - case IPC_SET: - if ((error = copyin(arg, &real_arg, sizeof(real_arg))) != 0) - goto done2; - if ((error = copyin(real_arg.buf, &sbuf, sizeof(sbuf))) != 0) - goto done2; - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_M))) - goto done2; - semaptr->sem_perm.uid = sbuf.sem_perm.uid; - semaptr->sem_perm.gid = sbuf.sem_perm.gid; - semaptr->sem_perm.mode = (semaptr->sem_perm.mode & ~0777) | - (sbuf.sem_perm.mode & 0777); - semaptr->sem_ctime = time (NULL); - break; - - case IPC_STAT: - if ((error = copyin(arg, &real_arg, sizeof(real_arg))) != 0) - goto done2; - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_R))) - goto done2; - sbuf = *semaptr; - mtx_unlock(sema_mtxp); - error = copyout(semaptr, real_arg.buf, - sizeof(struct semid_ds)); - break; - - case GETNCNT: - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_R))) - goto done2; - if (semnum < 0 || semnum >= semaptr->sem_nsems) { - error = EINVAL; - goto done2; - } - rval = semaptr->sem_base[semnum].semncnt; - break; - - case GETPID: - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_R))) - goto done2; - if (semnum < 0 || semnum >= semaptr->sem_nsems) { - error = EINVAL; - goto done2; - } - rval = semaptr->sem_base[semnum].sempid; - break; - - case GETVAL: - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_R))) - goto done2; - if (semnum < 0 || semnum >= semaptr->sem_nsems) { - error = EINVAL; - goto done2; - } - rval = semaptr->sem_base[semnum].semval; - break; - - case GETALL: - if ((error = copyin(arg, &real_arg, sizeof(real_arg))) != 0) - goto done2; - array = (u_short *) sys_malloc(sizeof(*array) * semaptr->sem_nsems, M_TEMP, - M_WAITOK); - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_R))) - goto done2; - for (i = 0; i < semaptr->sem_nsems; i++) - array[i] = semaptr->sem_base[i].semval; - mtx_unlock(sema_mtxp); - error = copyout(array, real_arg.array, - i * sizeof(real_arg.array[0])); - break; - - case GETZCNT: - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_R))) - goto done2; - if (semnum < 0 || semnum >= semaptr->sem_nsems) { - error = EINVAL; - goto done2; - } - rval = semaptr->sem_base[semnum].semzcnt; - break; - - case SETVAL: - if ((error = copyin(arg, &real_arg, sizeof(real_arg))) != 0) - goto done2; - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_W))) - goto done2; - if (semnum < 0 || semnum >= semaptr->sem_nsems) { - error = EINVAL; - goto done2; - } - if (real_arg.val < 0 || real_arg.val > seminfo.semvmx) { - error = ERANGE; - goto done2; - } - semaptr->sem_base[semnum].semval = real_arg.val; - SEMUNDO_LOCK(); - semundo_clear(semid, semnum); - SEMUNDO_UNLOCK(); - wakeup(semaptr); - break; - - case SETALL: - mtx_lock(sema_mtxp); -raced: - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - count = semaptr->sem_nsems; - mtx_unlock(sema_mtxp); - if ((error = copyin(arg, &real_arg, sizeof(real_arg))) != 0) - goto done2; - array = (u_short *) sys_malloc(sizeof(*array) * count, M_TEMP, M_WAITOK); - copyin(real_arg.array, array, count * sizeof(*array)); - if (error) - break; - mtx_lock(sema_mtxp); - if ((error = semvalid(uap->semid, semaptr)) != 0) - goto done2; - /* we could have raced? */ - if (count != semaptr->sem_nsems) { - sys_free(array, M_TEMP); - array = NULL; - goto raced; - } - if ((error = ipcperm(td, &semaptr->sem_perm, IPC_W))) - goto done2; - for (i = 0; i < semaptr->sem_nsems; i++) { - usval = array[i]; - if (usval > seminfo.semvmx) { - error = ERANGE; - break; - } - semaptr->sem_base[i].semval = usval; - } - SEMUNDO_LOCK(); - semundo_clear(semid, -1); - SEMUNDO_UNLOCK(); - wakeup(semaptr); - break; - - default: - error = EINVAL; - break; - } - - if (error == 0) - td->td_retval[0] = rval; -done2: - if (mtx_owned(sema_mtxp)) - mtx_unlock(sema_mtxp); - if (array != NULL) - sys_free(array, M_TEMP); - return(error); -} - -#ifndef _SYS_SYSPROTO_H_ -struct semget_args { - key_t key; - int nsems; - int semflg; -}; -#endif - -/* - * MPSAFE - */ -int -semget(struct thread *td, struct semget_args *uap) -{ - int semid, error = 0; - key_t key = uap->key; - int nsems = uap->nsems; - int semflg = uap->semflg; -#ifndef __CYGWIN__ - struct ucred *cred = td->td_ucred; -#endif - - DPRINTF(("semget(0x%x, %d, 0%o)\n", key, nsems, semflg)); - if (!jail_sysvipc_allowed && jailed(td->td_ucred)) - return (ENOSYS); - - mtx_lock(&Giant); - if (key != IPC_PRIVATE) { - for (semid = 0; semid < seminfo.semmni; semid++) { - if ((sema[semid].sem_perm.mode & SEM_ALLOC) && - sema[semid].sem_perm.key == key) - break; - } - if (semid < seminfo.semmni) { - DPRINTF(("found public key\n")); - if ((error = ipcperm(td, &sema[semid].sem_perm, - semflg & 0700))) { - goto done2; - } - if (nsems > 0 && sema[semid].sem_nsems < nsems) { - DPRINTF(("too small\n")); - error = EINVAL; - goto done2; - } - if ((semflg & IPC_CREAT) && (semflg & IPC_EXCL)) { - DPRINTF(("not exclusive\n")); - error = EEXIST; - goto done2; - } - goto found; - } - } - - DPRINTF(("need to allocate the semid_ds\n")); - if (key == IPC_PRIVATE || (semflg & IPC_CREAT)) { - if (nsems <= 0 || nsems > seminfo.semmsl) { - DPRINTF(("nsems out of range (0<%d<=%d)\n", nsems, - seminfo.semmsl)); - error = EINVAL; - goto done2; - } - if (nsems > seminfo.semmns - semtot) { - DPRINTF(( - "not enough semaphores left (need %d, got %d)\n", - nsems, seminfo.semmns - semtot)); - error = ENOSPC; - goto done2; - } - for (semid = 0; semid < seminfo.semmni; semid++) { - if ((sema[semid].sem_perm.mode & SEM_ALLOC) == 0) - break; - } - if (semid == seminfo.semmni) { - DPRINTF(("no more semid_ds's available\n")); - error = ENOSPC; - goto done2; - } - DPRINTF(("semid %d is available\n", semid)); - sema[semid].sem_perm.key = key; -#ifdef __CYGWIN__ - sema[semid].sem_perm.cuid = td->ipcblk->uid; - sema[semid].sem_perm.uid = td->ipcblk->uid; - sema[semid].sem_perm.cgid = td->ipcblk->gid; - sema[semid].sem_perm.gid = td->ipcblk->gid; -#else - sema[semid].sem_perm.cuid = cred->cr_uid; - sema[semid].sem_perm.uid = cred->cr_uid; - sema[semid].sem_perm.cgid = cred->cr_gid; - sema[semid].sem_perm.gid = cred->cr_gid; -#endif - sema[semid].sem_perm.mode = (semflg & 0777) | SEM_ALLOC; - sema[semid].sem_perm.seq = - (sema[semid].sem_perm.seq + 1) & 0x7fff; - sema[semid].sem_nsems = nsems; - sema[semid].sem_otime = 0; - sema[semid].sem_ctime = time (NULL); - sema[semid].sem_base = &sem[semtot]; - semtot += nsems; - semtots++; - bzero(sema[semid].sem_base, - sizeof(sema[semid].sem_base[0])*nsems); - DPRINTF(("sembase = 0x%x, next = 0x%x\n", sema[semid].sem_base, - &sem[semtot])); - } else { - DPRINTF(("didn't find it and wasn't asked to create it\n")); - error = ENOENT; - goto done2; - } - -found: - td->td_retval[0] = IXSEQ_TO_IPCID(semid, sema[semid].sem_perm); -done2: -#ifdef __CYGWIN__ - if (!error) - ipcexit_creat_hookthread (td); -#endif - mtx_unlock(&Giant); - return (error); -} - -#ifndef _SYS_SYSPROTO_H_ -struct semop_args { - int semid; - struct sembuf *sops; - size_t nsops; -}; -#endif - -/* - * MPSAFE - */ -int -semop(struct thread *td, struct semop_args *uap) -{ - int semid = uap->semid; - size_t nsops = uap->nsops; - struct sembuf *sops; - struct semid_ds *semaptr; - struct sembuf *sopptr = 0; - struct sem *semptr = 0; - struct sem_undo *suptr; - struct mtx *sema_mtxp; - size_t i, j, k; - int error; - int do_wakeup, do_undos; - - DPRINTF(("call to semop(%d, 0x%x, %u)\n", semid, uap->sops, nsops)); - - if (!jail_sysvipc_allowed && jailed(td->td_ucred)) - return (ENOSYS); - - semid = IPCID_TO_IX(semid); /* Convert back to zero origin */ - - if (semid < 0 || semid >= seminfo.semmni) - return (EINVAL); - - /* Allocate memory for sem_ops */ - if (nsops > (unsigned long) seminfo.semopm) { - DPRINTF(("too many sops (max=%d, nsops=%d)\n", seminfo.semopm, - nsops)); - return (E2BIG); - } - sops = (struct sembuf *) sys_malloc(nsops * sizeof(sops[0]), M_SEM, M_WAITOK); - if ((error = copyin(uap->sops, sops, nsops * sizeof(sops[0]))) != 0) { - DPRINTF(("error = %d from copyin(%08x, %08x, %d)\n", error, - uap->sops, sops, nsops * sizeof(sops[0]))); - sys_free(sops, M_SEM); - return (error); - } - - semaptr = &sema[semid]; - sema_mtxp = &sema_mtx[semid]; - mtx_lock(sema_mtxp); - if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0) { - error = EINVAL; - goto done2; - } - if (semaptr->sem_perm.seq != IPCID_TO_SEQ(uap->semid)) { - error = EINVAL; - goto done2; - } - /* - * Initial pass thru sops to see what permissions are needed. - * Also perform any checks that don't need repeating on each - * attempt to satisfy the request vector. - */ - j = 0; /* permission needed */ - do_undos = 0; - for (i = 0; i < nsops; i++) { - sopptr = &sops[i]; - if (sopptr->sem_num >= semaptr->sem_nsems) { - error = EFBIG; - goto done2; - } - if (sopptr->sem_flg & SEM_UNDO && sopptr->sem_op != 0) - do_undos = 1; - j |= (sopptr->sem_op == 0) ? SEM_R : SEM_A; - } - - if ((error = ipcperm(td, &semaptr->sem_perm, j))) { - DPRINTF(("error = %d from ipaccess\n", error)); - goto done2; - } - - /* - * Loop trying to satisfy the vector of requests. - * If we reach a point where we must wait, any requests already - * performed are rolled back and we go to sleep until some other - * process wakes us up. At this point, we start all over again. - * - * This ensures that from the perspective of other tasks, a set - * of requests is atomic (never partially satisfied). - */ - for (;;) { - do_wakeup = 0; - error = 0; /* error return if necessary */ - - for (i = 0; i < nsops; i++) { - sopptr = &sops[i]; - semptr = &semaptr->sem_base[sopptr->sem_num]; - - DPRINTF(( - "semop: semaptr=%x, sem_base=%x, " - "semptr=%x, sem[%d]=%d : op=%d, flag=%s\n", - semaptr, semaptr->sem_base, semptr, - sopptr->sem_num, semptr->semval, sopptr->sem_op, - (sopptr->sem_flg & IPC_NOWAIT) ? - "nowait" : "wait")); - - if (sopptr->sem_op < 0) { - if (semptr->semval + sopptr->sem_op < 0) { - DPRINTF(("semop: can't do it now\n")); - break; - } else { - semptr->semval += sopptr->sem_op; - if (semptr->semval == 0 && - semptr->semzcnt > 0) - do_wakeup = 1; - } - } else if (sopptr->sem_op == 0) { - if (semptr->semval != 0) { - DPRINTF(("semop: not zero now\n")); - break; - } - } else if (semptr->semval + sopptr->sem_op > - seminfo.semvmx) { - error = ERANGE; - break; - } else { - if (semptr->semncnt > 0) - do_wakeup = 1; - semptr->semval += sopptr->sem_op; - } - } - - /* - * Did we get through the entire vector? - */ - if (i >= nsops) - goto done; - - /* - * No ... rollback anything that we've already done - */ - DPRINTF(("semop: rollback 0 through %d\n", i-1)); - for (j = 0; j < i; j++) - semaptr->sem_base[sops[j].sem_num].semval -= - sops[j].sem_op; - - /* If we detected an error, return it */ - if (error != 0) - goto done2; - - /* - * If the request that we couldn't satisfy has the - * NOWAIT flag set then return with EAGAIN. - */ - if (sopptr->sem_flg & IPC_NOWAIT) { - error = EAGAIN; - goto done2; - } - - if (sopptr->sem_op == 0) - semptr->semzcnt++; - else - semptr->semncnt++; - - DPRINTF(("semop: good night!\n")); - error = msleep(semaptr, sema_mtxp, (PZERO - 4) | PCATCH, - "semwait", 0); - DPRINTF(("semop: good morning (error=%d)!\n", error)); - - if (error != 0) { -#ifdef __CYGWIN__ - if (error != EIDRM) -#endif /* __CYGWIN__ */ - error = EINTR; - goto done2; - } - DPRINTF(("semop: good morning!\n")); - - /* - * Make sure that the semaphore still exists - */ - if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0 || - semaptr->sem_perm.seq != IPCID_TO_SEQ(uap->semid)) { - error = EIDRM; - goto done2; - } - - /* - * The semaphore is still alive. Readjust the count of - * waiting processes. - */ - if (sopptr->sem_op == 0) - semptr->semzcnt--; - else - semptr->semncnt--; - } - -done: - /* - * Process any SEM_UNDO requests. - */ - if (do_undos) { - SEMUNDO_LOCK(); - suptr = NULL; - for (i = 0; i < nsops; i++) { - /* - * We only need to deal with SEM_UNDO's for non-zero - * op's. - */ - int adjval; - - if ((sops[i].sem_flg & SEM_UNDO) == 0) - continue; - adjval = sops[i].sem_op; - if (adjval == 0) - continue; - error = semundo_adjust(td, &suptr, semid, - sops[i].sem_num, -adjval); - if (error == 0) - continue; - - /* - * Oh-Oh! We ran out of either sem_undo's or undo's. - * Rollback the adjustments to this point and then - * rollback the semaphore ups and down so we can return - * with an error with all structures restored. We - * rollback the undo's in the exact reverse order that - * we applied them. This guarantees that we won't run - * out of space as we roll things back out. - */ - for (j = 0; j < i; j++) { - k = i - j - 1; - if ((sops[k].sem_flg & SEM_UNDO) == 0) - continue; - adjval = sops[k].sem_op; - if (adjval == 0) - continue; - if (semundo_adjust(td, &suptr, semid, - sops[k].sem_num, adjval) != 0) - panic("semop - can't undo undos"); - } - - for (j = 0; j < nsops; j++) - semaptr->sem_base[sops[j].sem_num].semval -= - sops[j].sem_op; - - DPRINTF(("error = %d from semundo_adjust\n", error)); - SEMUNDO_UNLOCK(); - goto done2; - } /* loop through the sops */ - SEMUNDO_UNLOCK(); - } /* if (do_undos) */ - - /* We're definitely done - set the sempid's and time */ - for (i = 0; i < nsops; i++) { - sopptr = &sops[i]; - semptr = &semaptr->sem_base[sopptr->sem_num]; - semptr->sempid = td->td_proc->p_pid; - } - semaptr->sem_otime = time (NULL); - - /* - * Do a wakeup if any semaphore was up'd whilst something was - * sleeping on it. - */ - if (do_wakeup) { - DPRINTF(("semop: doing wakeup\n")); - wakeup(semaptr); - DPRINTF(("semop: back from wakeup\n")); - } - DPRINTF(("semop: done\n")); - td->td_retval[0] = 0; -done2: - mtx_unlock(sema_mtxp); - sys_free(sops, M_SEM); - return (error); -} - -/* - * Go through the undo structures for this process and apply the adjustments to - * semaphores. - */ -void -semexit_myhook(void *arg, struct proc *p) -{ - struct sem_undo *suptr; - struct sem_undo **supptr; - -#ifdef __CYGWIN__ - /* - * Search all mutexes, if some of them are still owned by the - * leaving process. If so, unlock them. - */ - if (sem_mtx.owner == p->winpid) - mtx_unlock(&sem_mtx); - for (int i = 0; i < seminfo.semmni; i++) - if (sema_mtx[i].owner == p->winpid) - mtx_unlock(&sema_mtx[i]); -#endif /* __CYGWIN__ */ - - /* - * Go through the chain of undo vectors looking for one - * associated with this process. - */ - SEMUNDO_HOOKLOCK(); - SLIST_FOREACH_PREVPTR(suptr, supptr, &semu_list, un_next) { - if (suptr->un_proc == p) - break; - } - SEMUNDO_UNLOCK(); - - if (suptr == NULL) - return; - - DPRINTF(("proc @%08x has undo structure with %d entries\n", p, - suptr->un_cnt)); - - /* - * If there are any active undo elements then process them. - */ - if (suptr->un_cnt > 0) { - int ix; - - for (ix = 0; ix < suptr->un_cnt; ix++) { - int semid = suptr->un_ent[ix].un_id; - int semnum = suptr->un_ent[ix].un_num; - int adjval = suptr->un_ent[ix].un_adjval; - struct semid_ds *semaptr; - struct mtx *sema_mtxp; - - semaptr = &sema[semid]; - sema_mtxp = &sema_mtx[semid]; -#ifdef __CYGWIN__ - _mtx_lock(sema_mtxp, p->winpid, __FILE__, __LINE__); -#else - mtx_lock(sema_mtxp); -#endif - SEMUNDO_HOOKLOCK(); - if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0) - panic("semexit - semid not allocated"); - if (semnum >= semaptr->sem_nsems) - panic("semexit - semnum out of range"); - - DPRINTF(( - "semexit: %08x id=%d num=%d(adj=%d) ; sem=%d\n", - suptr->un_proc, suptr->un_ent[ix].un_id, - suptr->un_ent[ix].un_num, - suptr->un_ent[ix].un_adjval, - semaptr->sem_base[semnum].semval)); - - if (adjval < 0) { - if (semaptr->sem_base[semnum].semval < -adjval) - semaptr->sem_base[semnum].semval = 0; - else - semaptr->sem_base[semnum].semval += - adjval; - } else - semaptr->sem_base[semnum].semval += adjval; - - wakeup(semaptr); - DPRINTF(("semexit: back from wakeup\n")); - mtx_unlock(sema_mtxp); - SEMUNDO_UNLOCK(); - } - } - - /* - * Deallocate the undo vector. - */ - DPRINTF(("removing vector\n")); - suptr->un_proc = NULL; - *supptr = SLIST_NEXT(suptr, un_next); -} - -#ifndef __CYGWIN__ -static int -sysctl_sema(SYSCTL_HANDLER_ARGS) -{ - - return (SYSCTL_OUT(req, sema, - sizeof(struct semid_ds) * seminfo.semmni)); -} -#endif /* __CYGWIN__ */ -#endif /* __OUTSIDE_CYGWIN__ */ |