1390 lines
34 KiB
C++
1390 lines
34 KiB
C++
/*
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* Implementation of SVID semaphores
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*
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* Author: Daniel Boulet
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*
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* This software is provided ``AS IS'' without any warranties of any kind.
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*/
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/*
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* This file is heavily changed to become part of Cygwin's cygserver.
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*/
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#ifdef __OUTSIDE_CYGWIN__
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#include "woutsup.h"
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#include <stdio.h>
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#include <sys/cygwin.h>
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#include <sys/cdefs.h>
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#ifndef __FBSDID
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#define __FBSDID(s) const char version[] = (s)
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#endif
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__FBSDID("$FreeBSD: /repoman/r/ncvs/src/sys/kern/sysv_sem.c,v 1.70 2004/05/30 20:34:58 phk Exp $");
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/* CV, 2006-01-09: Inspected upstream up to version 1.78. */
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#define _KERNEL 1
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#define __BSD_VISIBLE 1
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#include <sys/types.h>
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#include <sys/ipc.h>
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#include <sys/param.h>
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#include <sys/sysproto.h>
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#include <sys/lock.h>
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#include <sys/sem.h>
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#include <sys/queue.h>
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#include <malloc.h>
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#include <errno.h>
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#include <time.h>
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#include "cygserver.h"
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#include "process.h"
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#include "cygserver_ipc.h"
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#include <sys/smallprint.h>
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#ifdef __CYGWIN__
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#define __semctl semctl
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#define __semctl_args semctl_args
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#define SEM_DEBUG
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#endif /* __CYGWIN__ */
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#ifdef SEM_DEBUG
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#define DPRINTF(a) debug_printf a
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#else
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#define DPRINTF(a)
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#endif
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static int semvalid(int semid, struct semid_ds *semaptr);
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static struct sem_undo *semu_alloc(struct thread *td);
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static int semundo_adjust(struct thread *td, struct sem_undo **supptr,
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int semid, int semnum, int adjval);
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static void semundo_clear(int semid, int semnum, struct thread *td);
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#ifndef _SYS_SYSPROTO_H_
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struct __semctl_args;
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int __semctl(struct thread *td, struct __semctl_args *uap);
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struct semget_args;
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int semget(struct thread *td, struct semget_args *uap);
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struct semop_args;
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int semop(struct thread *td, struct semop_args *uap);
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#endif
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#ifndef __CYGWIN__
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/* XXX casting to (sy_call_t *) is bogus, as usual. */
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static sy_call_t *semcalls[] = {
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(sy_call_t *)__semctl, (sy_call_t *)semget,
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(sy_call_t *)semop
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};
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#endif
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static struct mtx sem_mtx; /* semaphore global lock */
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static int semtots = 0;
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static int semtot = 0;
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static struct semid_ds *sema; /* semaphore id pool */
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static struct mtx *sema_mtx; /* semaphore id pool mutexes*/
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static struct sem *sem; /* semaphore pool */
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static SLIST_HEAD(, sem_undo) semu_list; /* list of active undo structures */
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static int *semu; /* undo structure pool */
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#ifndef __CYGWIN__
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static eventhandler_tag semexit_tag;
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#endif /* __CYGWIN__ */
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#define SEMUNDO_MTX sem_mtx
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#define SEMUNDO_LOCK() mtx_lock(&SEMUNDO_MTX);
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#define SEMUNDO_HOOKLOCK() _mtx_lock(&SEMUNDO_MTX, p->winpid, __FILE__, __LINE__);
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#define SEMUNDO_UNLOCK() mtx_unlock(&SEMUNDO_MTX);
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#define SEMUNDO_LOCKASSERT(how,pid) mtx_assert(&SEMUNDO_MTX, (how), (pid));
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struct sem {
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u_short semval; /* semaphore value */
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pid_t sempid; /* pid of last operation */
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u_short semncnt; /* # awaiting semval > cval */
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u_short semzcnt; /* # awaiting semval = 0 */
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};
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/*
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* Undo structure (one per process)
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*/
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struct undo {
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short un_adjval; /* adjust on exit values */
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short un_num; /* semaphore # */
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int un_id; /* semid */
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} un_ent[1]; /* undo entries */
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struct sem_undo {
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SLIST_ENTRY(sem_undo) un_next; /* ptr to next active undo structure */
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#ifdef __CYGWIN__
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DWORD un_proc; /* owner of this structure */
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#else
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struct proc *un_proc; /* owner of this structure */
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#endif
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short un_cnt; /* # of active entries */
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struct undo un_ent[1]; /* undo entries */
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};
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/*
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* Configuration parameters
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*/
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#ifndef SEMMNI
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#define SEMMNI 10 /* # of semaphore identifiers */
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#endif
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#ifndef SEMMNS
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#define SEMMNS 60 /* # of semaphores in system */
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#endif
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#ifndef SEMUME
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#define SEMUME 10 /* max # of undo entries per process */
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#endif
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#ifndef SEMMNU
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#define SEMMNU 30 /* # of undo structures in system */
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#endif
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/* shouldn't need tuning */
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#ifndef SEMMAP
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#define SEMMAP 30 /* # of entries in semaphore map */
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#endif
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#ifndef SEMMSL
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#define SEMMSL SEMMNS /* max # of semaphores per id */
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#endif
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#ifndef SEMOPM
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#define SEMOPM 100 /* max # of operations per semop call */
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#endif
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#ifndef SEMVMX
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#define SEMVMX 32767 /* semaphore maximum value */
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#endif
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#ifndef SEMAEM
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#define SEMAEM 16384 /* adjust on exit max value */
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#endif
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#ifdef __CYGWIN__
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/* gcc 3.4 defines a new offsetof which is different for C++. Since this
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file is just a derived plain-C file, we need to revert to the plain-C
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definition of offsetof. */
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#ifdef offsetof
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#undef offsetof
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#endif
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#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
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#endif /* __CYGWIN__ */
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/*
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* Due to the way semaphore memory is allocated, we have to ensure that
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* SEMUSZ is properly aligned.
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*/
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#define SEM_ALIGN(bytes) (((bytes) + (sizeof(long) - 1)) & ~(sizeof(long) - 1))
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/* actual size of an undo structure */
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#define SEMUSZ SEM_ALIGN(offsetof(struct sem_undo, un_ent[SEMUME]))
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/*
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* Macro to find a particular sem_undo vector
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*/
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#define SEMU(ix) \
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((struct sem_undo *)(((intptr_t)semu)+ix * seminfo.semusz))
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/*
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* semaphore info struct
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*/
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struct seminfo seminfo = {
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SEMMNI, /* # of semaphore identifiers */
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SEMMNS, /* # of semaphores in system */
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SEMMSL, /* max # of semaphores per id */
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SEMOPM, /* max # of operations per semop call */
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SEMMNU, /* # of undo structures in system */
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SEMUME, /* max # of undo entries per process */
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SEMVMX, /* semaphore maximum value */
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SEMAEM, /* adjust on exit max value */
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SEMMAP, /* # of entries in semaphore map */
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SEMUSZ /* size in bytes of undo structure */
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};
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#ifndef __CYGWIN__
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SYSCTL_DECL(_kern_ipc);
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SYSCTL_INT(_kern_ipc, OID_AUTO, semmap, CTLFLAG_RW, &seminfo.semmap, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semmni, CTLFLAG_RDTUN, &seminfo.semmni, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semmns, CTLFLAG_RDTUN, &seminfo.semmns, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semmnu, CTLFLAG_RDTUN, &seminfo.semmnu, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semmsl, CTLFLAG_RW, &seminfo.semmsl, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semopm, CTLFLAG_RDTUN, &seminfo.semopm, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semume, CTLFLAG_RDTUN, &seminfo.semume, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semusz, CTLFLAG_RDTUN, &seminfo.semusz, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semvmx, CTLFLAG_RW, &seminfo.semvmx, 0, "");
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SYSCTL_INT(_kern_ipc, OID_AUTO, semaem, CTLFLAG_RW, &seminfo.semaem, 0, "");
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SYSCTL_PROC(_kern_ipc, OID_AUTO, sema, CTLFLAG_RD,
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NULL, 0, sysctl_sema, "", "");
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#endif /* __CYGWIN__ */
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void
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seminit(void)
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{
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int i;
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TUNABLE_INT_FETCH("kern.ipc.semmap", &seminfo.semmap);
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TUNABLE_INT_FETCH("kern.ipc.semmni", &seminfo.semmni);
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TUNABLE_INT_FETCH("kern.ipc.semmns", &seminfo.semmns);
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TUNABLE_INT_FETCH("kern.ipc.semmnu", &seminfo.semmnu);
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TUNABLE_INT_FETCH("kern.ipc.semmsl", &seminfo.semmsl);
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TUNABLE_INT_FETCH("kern.ipc.semopm", &seminfo.semopm);
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TUNABLE_INT_FETCH("kern.ipc.semume", &seminfo.semume);
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TUNABLE_INT_FETCH("kern.ipc.semusz", &seminfo.semusz);
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TUNABLE_INT_FETCH("kern.ipc.semvmx", &seminfo.semvmx);
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TUNABLE_INT_FETCH("kern.ipc.semaem", &seminfo.semaem);
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#ifdef __CYGWIN__
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/* It's too dangerous a setting to leave it alone.
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Keep that clean here. */
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seminfo.semusz = SEM_ALIGN(offsetof(struct sem_undo,
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un_ent[seminfo.semume]));
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#endif /* __CYGWIN__ */
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sem = (struct sem *) sys_malloc(sizeof(struct sem) * seminfo.semmns, M_SEM, M_WAITOK);
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sema = (struct semid_ds *) sys_malloc(sizeof(struct semid_ds) * seminfo.semmni, M_SEM,
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M_WAITOK);
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sema_mtx = (struct mtx *) sys_malloc(sizeof(struct mtx) * seminfo.semmni, M_SEM,
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M_WAITOK | M_ZERO);
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semu = (int *) sys_malloc(seminfo.semmnu * seminfo.semusz, M_SEM, M_WAITOK);
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for (i = 0; i < seminfo.semmni; i++) {
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sema[i].sem_base = 0;
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sema[i].sem_perm.mode = 0;
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sema[i].sem_perm.seq = 0;
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}
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for (i = 0; i < seminfo.semmni; i++)
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{
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char *buf = (char *) sys_malloc(16, M_SEM, M_WAITOK);
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snprintf(buf, 16, "semid[%d]", i);
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mtx_init(&sema_mtx[i], buf, NULL, MTX_DEF);
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}
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for (i = 0; i < seminfo.semmnu; i++) {
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struct sem_undo *suptr = SEMU(i);
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#ifdef __CYGWIN__
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suptr->un_proc = 0;
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#else
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suptr->un_proc = NULL;
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#endif
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}
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SLIST_INIT(&semu_list);
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mtx_init(&sem_mtx, "sem", NULL, MTX_DEF);
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#ifndef __CYGWIN__
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semexit_tag = EVENTHANDLER_REGISTER(process_exit, semexit_myhook, NULL,
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EVENTHANDLER_PRI_ANY);
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#endif /* __CYGWIN__ */
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}
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int
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semunload(void)
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{
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#ifndef __CYGWIN__ /* Would result in being unable to shutdown the
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server gracefully. */
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if (semtot != 0)
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return (EBUSY);
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EVENTHANDLER_DEREGISTER(process_exit, semexit_tag);
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#endif /* __CYGWIN__ */
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sys_free(sem, M_SEM);
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sys_free(sema, M_SEM);
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sys_free(semu, M_SEM);
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for (int i = 0; i < seminfo.semmni; i++) {
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sys_free((void *) sema_mtx[i].name, M_SEM);
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mtx_destroy(&sema_mtx[i]);
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}
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mtx_destroy(&sem_mtx);
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return (0);
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}
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#ifndef __CYGWIN__
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static int
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sysvsem_modload(struct module *module, int cmd, void *arg)
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{
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int error = 0;
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switch (cmd) {
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case MOD_LOAD:
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seminit();
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break;
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case MOD_UNLOAD:
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error = semunload();
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break;
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case MOD_SHUTDOWN:
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break;
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default:
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error = EINVAL;
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break;
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}
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return (error);
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}
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static moduledata_t sysvsem_mod = {
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"sysvsem",
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&sysvsem_modload,
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NULL
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};
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SYSCALL_MODULE_HELPER(semsys);
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SYSCALL_MODULE_HELPER(__semctl);
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SYSCALL_MODULE_HELPER(semget);
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SYSCALL_MODULE_HELPER(semop);
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DECLARE_MODULE(sysvsem, sysvsem_mod,
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SI_SUB_SYSV_SEM, SI_ORDER_FIRST);
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MODULE_VERSION(sysvsem, 1);
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/*
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* Entry point for all SEM calls
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*
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* MPSAFE
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*/
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int
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semsys(td, uap)
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struct thread *td;
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/* XXX actually varargs. */
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struct semsys_args /* {
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int which;
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int a2;
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int a3;
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int a4;
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int a5;
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} */ *uap;
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{
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int error;
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if (!jail_sysvipc_allowed && jailed(td->td_ucred))
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return (ENOSYS);
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if (uap->which < 0 ||
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uap->which >= sizeof(semcalls)/sizeof(semcalls[0]))
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return (EINVAL);
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error = (*semcalls[uap->which])(td, &uap->a2);
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return (error);
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}
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#endif /* __CYGWIN__ */
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/*
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* Allocate a new sem_undo structure for a process
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* (returns ptr to structure or NULL if no more room)
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*/
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static struct sem_undo *
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semu_alloc(struct thread *td)
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{
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int i;
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struct sem_undo *suptr;
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struct sem_undo **supptr;
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int attempt;
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SEMUNDO_LOCKASSERT(MA_OWNED, td->td_proc->winpid);
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/*
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* Try twice to allocate something.
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* (we'll purge an empty structure after the first pass so
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* two passes are always enough)
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*/
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for (attempt = 0; attempt < 2; attempt++) {
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/*
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* Look for a free structure.
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* Fill it in and return it if we find one.
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*/
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for (i = 0; i < seminfo.semmnu; i++) {
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suptr = SEMU(i);
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#ifdef __CYGWIN__
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if (suptr->un_proc == 0) {
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#else
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if (suptr->un_proc == NULL) {
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#endif
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SLIST_INSERT_HEAD(&semu_list, suptr, un_next);
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suptr->un_cnt = 0;
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suptr->un_proc = td->td_proc->winpid;
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return(suptr);
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}
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}
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/*
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* We didn't find a free one, if this is the first attempt
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* then try to free a structure.
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*/
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if (attempt == 0) {
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/* All the structures are in use - try to free one */
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int did_something = 0;
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SLIST_FOREACH_PREVPTR(suptr, supptr, &semu_list,
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un_next) {
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if (suptr->un_cnt == 0) {
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#ifdef __CYGWIN__
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suptr->un_proc = 0;
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#else
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suptr->un_proc = NULL;
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#endif
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did_something = 1;
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*supptr = SLIST_NEXT(suptr, un_next);
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break;
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}
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}
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/* If we didn't free anything then just give-up */
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if (!did_something)
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return(NULL);
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} else {
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/*
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* The second pass failed even though we freed
|
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* something after the first pass!
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* This is IMPOSSIBLE!
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*/
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panic("semu_alloc - second attempt failed");
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}
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}
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return (NULL);
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}
|
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|
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/*
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* Adjust a particular entry for a particular proc
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*/
|
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|
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static int
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semundo_adjust(struct thread *td, struct sem_undo **supptr, int semid,
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int semnum, int adjval)
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{
|
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struct proc *p = td->td_proc;
|
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struct sem_undo *suptr;
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struct undo *sunptr;
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int i;
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SEMUNDO_LOCKASSERT(MA_OWNED, td->td_proc->winpid);
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/* Look for and remember the sem_undo if the caller doesn't provide
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it */
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suptr = *supptr;
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if (suptr == NULL) {
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SLIST_FOREACH(suptr, &semu_list, un_next) {
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#ifdef __CYGWIN__
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if (suptr->un_proc == p->winpid) {
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#else
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if (suptr->un_proc == p) {
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#endif
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*supptr = suptr;
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break;
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}
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}
|
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if (suptr == NULL) {
|
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if (adjval == 0)
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return(0);
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suptr = semu_alloc(td);
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if (suptr == NULL)
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return(ENOSPC);
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*supptr = suptr;
|
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}
|
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}
|
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|
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/*
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* Look for the requested entry and adjust it (delete if adjval becomes
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* 0).
|
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*/
|
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sunptr = &suptr->un_ent[0];
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for (i = 0; i < suptr->un_cnt; i++, sunptr++) {
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if (sunptr->un_id != semid || sunptr->un_num != semnum)
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continue;
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if (adjval != 0) {
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adjval += sunptr->un_adjval;
|
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if (adjval > seminfo.semaem || adjval < -seminfo.semaem)
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return (ERANGE);
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}
|
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sunptr->un_adjval = adjval;
|
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if (sunptr->un_adjval == 0) {
|
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suptr->un_cnt--;
|
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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 thread *td)
|
|
{
|
|
struct sem_undo *suptr;
|
|
|
|
SEMUNDO_LOCKASSERT(MA_OWNED, td->td_proc->winpid);
|
|
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, td);
|
|
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, td);
|
|
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);
|
|
error = 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, td);
|
|
SEMUNDO_UNLOCK();
|
|
wakeup(semaptr);
|
|
break;
|
|
|
|
default:
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (error == 0)
|
|
td->td_retval[0] = rval;
|
|
done2:
|
|
if (mtx_owned(sema_mtxp, td->td_proc->winpid))
|
|
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%llx, %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)
|
|
{
|
|
#define SMALL_SOPS 8
|
|
struct sembuf small_sops[SMALL_SOPS];
|
|
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 <= SMALL_SOPS)
|
|
sops = small_sops;
|
|
else if (nsops <= (unsigned long) seminfo.semopm)
|
|
sops = (struct sembuf *) sys_malloc(nsops * sizeof(*sops), M_SEM, M_WAITOK);
|
|
else {
|
|
DPRINTF(("too many sops (max=%d, nsops=%d)\n", seminfo.semopm,
|
|
nsops));
|
|
return (E2BIG);
|
|
}
|
|
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])));
|
|
if (sops != small_sops)
|
|
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));
|
|
/* return code is checked below, after sem[nz]cnt-- */
|
|
|
|
/*
|
|
* 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--;
|
|
|
|
/*
|
|
* Is it really morning, or was our sleep interrupted?
|
|
* (Delayed check of msleep() return code because we
|
|
* need to decrement sem[nz]cnt either way.)
|
|
*/
|
|
if (error != 0) {
|
|
#ifdef __CYGWIN__
|
|
if (error != EIDRM)
|
|
#endif /* __CYGWIN__ */
|
|
error = EINTR;
|
|
goto done2;
|
|
}
|
|
DPRINTF(("semop: good morning!\n"));
|
|
}
|
|
|
|
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);
|
|
if (sops != small_sops)
|
|
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;
|
|
|
|
/*
|
|
* 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) {
|
|
#ifdef __CYGWIN__
|
|
if (suptr->un_proc == p->winpid)
|
|
#else
|
|
if (suptr->un_proc == p)
|
|
#endif
|
|
break;
|
|
}
|
|
#ifndef __CYGWIN__
|
|
SEMUNDO_UNLOCK();
|
|
#endif
|
|
|
|
if (suptr == NULL) {
|
|
SEMUNDO_UNLOCK();
|
|
return;
|
|
}
|
|
|
|
#ifdef __CYGWIN__
|
|
DPRINTF(("proc @%u(%u) has undo structure with %d entries\n",
|
|
p->cygpid, p->winpid, suptr->un_cnt));
|
|
#else
|
|
DPRINTF(("proc @%08x has undo structure with %d entries\n", p,
|
|
suptr->un_cnt));
|
|
#endif
|
|
|
|
/*
|
|
* 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);
|
|
SEMUNDO_HOOKLOCK();
|
|
#endif
|
|
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((
|
|
#ifdef __CYGWIN__
|
|
"semexit: %u id=%d num=%d(adj=%d) ; sem=%d\n",
|
|
#else
|
|
"semexit: %08x id=%d num=%d(adj=%d) ; sem=%d\n",
|
|
#endif
|
|
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, __FILE__, __LINE__);
|
|
#ifndef __CYGWIN__
|
|
SEMUNDO_UNLOCK();
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Deallocate the undo vector.
|
|
*/
|
|
DPRINTF(("removing vector (%u)\n", suptr->un_proc));
|
|
#ifdef __CYGWIN__
|
|
suptr->un_proc = 0;
|
|
#else
|
|
suptr->un_proc = NULL;
|
|
#endif
|
|
*supptr = SLIST_NEXT(suptr, un_next);
|
|
#ifdef __CYGWIN__
|
|
SEMUNDO_UNLOCK();
|
|
#endif
|
|
}
|
|
|
|
#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__ */
|