sys/kern/kern_p1003_1b.c

   1 /*
   2  * Copyright (c) 1996, 1997, 1998
   3  *      HD Associates, Inc.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by HD Associates, Inc
  16  * 4. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY HD ASSOCIATES AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL HD ASSOCIATES OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * $FreeBSD: src/sys/posix4/p1003_1b.c,v 1.5.2.2 2003/03/25 06:13:35 rwatson Exp $
  33  * $DragonFly: src/sys/kern/kern_p1003_1b.c,v 1.10 2007/06/26 19:31:08 dillon Exp $
  34  */
  35
  36 /* p1003_1b: Real Time common code.
  37  */
  38
  39 #include <sys/param.h>
  40 #include <sys/systm.h>
  41 #include <sys/kernel.h>
  42 #include <sys/sysent.h>
  43 #include <sys/posix4.h>
  44 #include <sys/proc.h>
  45 #include <sys/syslog.h>
  46 #include <sys/module.h>
  47 #include <sys/sysproto.h>
  48 #include <sys/sysctl.h>
  49
  50 MALLOC_DEFINE(M_P31B, "p1003.1b", "Posix 1003.1B");
  51
  52 /* p31b_proc: Return a proc struct corresponding to a pid to operate on.
  53  *
  54  * Enforce permission policy.
  55  *
  56  * The policy is the same as for sending signals except there
  57  * is no notion of process groups.
  58  *
  59  * pid == 0 means my process.
  60  *
  61  * This is disabled until I've got a permission gate in again:
  62  * only root can do this.
  63  */
  64
  65 #if 0
  66 /*
  67  * This is stolen from CANSIGNAL in kern_sig:
  68  *
  69  * Can process p, with pcred pc, do "write flavor" operations to process q?
  70  */
  71 #define CAN_AFFECT(p, cr, q) \
  72         ((cr)->cr_uid == 0 || \
  73             (cr)->cr_ruid == (q)->p_ucred->cr_ruid || \
  74             (cr)->cr_uid == (q)->p_ucred->cr_ruid || \
  75             (cr)->cr_ruid == (q)->p_ucred->cr_uid || \
  76             (cr)->cr_uid == (q)->p_ucred->cr_uid)
  77 #else
  78 #define CAN_AFFECT(p, cr, q) ((cr)->cr_uid == 0)
  79 #endif
  80
  81 /*
  82  * p31b_proc: Look up a proc from a PID.  If proc is 0 it is
  83  * my own proc.
  84  */
  85 int p31b_proc(struct proc *p, pid_t pid, struct proc **pp)
  86 {
  87         int ret = 0;
  88         struct proc *other_proc = 0;
  89
  90         if (pid == 0)
  91                 other_proc = p;
  92         else
  93                 other_proc = pfind(pid);
  94
  95         if (other_proc)
  96         {
  97                 /* Enforce permission policy.
  98                  */
  99                 if (CAN_AFFECT(p, p->p_ucred, other_proc))
 100                         *pp = other_proc;
 101                 else
 102                         ret = EPERM;
 103         }
 104         else
 105                 ret = ESRCH;
 106
 107         return ret;
 108 }
 109
 110
 111 #if !defined(_KPOSIX_PRIORITY_SCHEDULING)
 112
 113 int syscall_not_present(const char *s);
 114
 115 /* The system calls return ENOSYS if an entry is called that is
 116  * not run-time supported.  I am also logging since some programs
 117  * start to use this when they shouldn't.  That will be removed if annoying.
 118  */
 119 int syscall_not_present(const char *s)
 120 {
 121         struct proc *p = curproc;
 122         log(LOG_ERR, "cmd %s pid %d tried to use non-present %s\n",
 123                         p->p_comm, p->p_pid, s);
 124
 125         /* a " return nosys(p, uap); " here causes a core dump.
 126          */
 127
 128         return ENOSYS;
 129 }
 130
 131 /* Not configured but loadable via a module:
 132  */
 133
 134 static int sched_attach(void)
 135 {
 136         return 0;
 137 }
 138
 139 #define SYSCALL_NOT_PRESENT_GEN(SC) \
 140 int SC (struct SC##_args *uap) \
 141 { \
 142         return syscall_not_present(#SC); \
 143 }
 144
 145 SYSCALL_NOT_PRESENT_GEN(sched_setparam)
 146 SYSCALL_NOT_PRESENT_GEN(sched_getparam)
 147 SYSCALL_NOT_PRESENT_GEN(sched_setscheduler)
 148 SYSCALL_NOT_PRESENT_GEN(sched_getscheduler)
 149 SYSCALL_NOT_PRESENT_GEN(sched_yield)
 150 SYSCALL_NOT_PRESENT_GEN(sched_get_priority_max)
 151 SYSCALL_NOT_PRESENT_GEN(sched_get_priority_min)
 152 SYSCALL_NOT_PRESENT_GEN(sched_rr_get_interval)
 153
 154 #else
 155
 156 /* Configured in kernel version:
 157  */
 158 static struct ksched *ksched;
 159
 160 static int sched_attach(void)
 161 {
 162         int ret = ksched_attach(&ksched);
 163
 164         if (ret == 0)
 165                 p31b_setcfg(CTL_P1003_1B_PRIORITY_SCHEDULING, 1);
 166
 167         return ret;
 168 }
 169
 170 int
 171 sys_sched_setparam(struct sched_setparam_args *uap)
 172 {
 173         struct proc *p = curproc;
 174         struct lwp *lp;
 175         int e;
 176
 177         struct sched_param sched_param;
 178         copyin(uap->param, &sched_param, sizeof(sched_param));
 179
 180         if ((e = p31b_proc(p, uap->pid, &p)) == 0) {
 181                 lp = FIRST_LWP_IN_PROC(p); /* XXX lwp */
 182                 e = ksched_setparam(&uap->sysmsg_reg, ksched, lp,
 183                     (const struct sched_param *)&sched_param);
 184         }
 185         return e;
 186 }
 187
 188 int
 189 sys_sched_getparam(struct sched_getparam_args *uap)
 190 {
 191         struct proc *p = curproc;
 192         struct proc *targetp;
 193         struct lwp *lp;
 194         struct sched_param sched_param;
 195         int e;
 196
 197         if (uap->pid != 0 && uap->pid != p->p_pid) {
 198                 e = p31b_proc(p, uap->pid, &targetp);
 199                 if (e)
 200                         return e;
 201         } else {
 202                 targetp = p;
 203         }
 204
 205         lp = FIRST_LWP_IN_PROC(targetp); /* XXX lwp */
 206         e = ksched_getparam(&uap->sysmsg_reg, ksched, lp, &sched_param);
 207
 208         if (!e)
 209                 copyout(&sched_param, uap->param, sizeof(sched_param));
 210
 211         return e;
 212 }
 213
 214 int
 215 sys_sched_setscheduler(struct sched_setscheduler_args *uap)
 216 {
 217         struct proc *p = curproc;
 218         struct lwp *lp;
 219         int e;
 220
 221         struct sched_param sched_param;
 222         copyin(uap->param, &sched_param, sizeof(sched_param));
 223
 224         if ((e = p31b_proc(p, uap->pid, &p)) == 0) {
 225                 lp = FIRST_LWP_IN_PROC(p); /* XXX lwp */
 226                 e = ksched_setscheduler(&uap->sysmsg_reg, ksched, lp,
 227                     uap->policy, (const struct sched_param *)&sched_param);
 228         }
 229         return e;
 230 }
 231
 232 int
 233 sys_sched_getscheduler(struct sched_getscheduler_args *uap)
 234 {
 235         struct proc *p = curproc;
 236         struct proc *targetp;
 237         struct lwp *lp;
 238         int e;
 239
 240         if (uap->pid != 0 && uap->pid != p->p_pid) {
 241                 e = p31b_proc(p, uap->pid, &targetp);
 242                 if (e)
 243                         return e;
 244         } else {
 245                 targetp = p;
 246         }
 247
 248         lp = FIRST_LWP_IN_PROC(targetp); /* XXX lwp */
 249         e = ksched_getscheduler(&uap->sysmsg_reg, ksched, lp);
 250
 251         return e;
 252 }
 253
 254 int
 255 sys_sched_yield(struct sched_yield_args *uap)
 256 {
 257         return ksched_yield(&uap->sysmsg_reg, ksched);
 258 }
 259
 260 int
 261 sys_sched_get_priority_max(struct sched_get_priority_max_args *uap)
 262 {
 263         return ksched_get_priority_max(&uap->sysmsg_reg, ksched, uap->policy);
 264 }
 265
 266 int
 267 sys_sched_get_priority_min(struct sched_get_priority_min_args *uap)
 268 {
 269         return ksched_get_priority_min(&uap->sysmsg_reg, ksched, uap->policy);
 270 }
 271
 272 int
 273 sys_sched_rr_get_interval(struct sched_rr_get_interval_args *uap)
 274 {
 275         int e;
 276         struct proc *p = curproc;
 277         struct lwp *lp = curthread->td_lwp;
 278
 279         if ((e = p31b_proc(p, uap->pid, &p)) == 0) {
 280             e = ksched_rr_get_interval(&uap->sysmsg_reg, ksched,
 281                                        lp, uap->interval);
 282         }
 283         return e;
 284 }
 285
 286 #endif
 287
 288 static void p31binit(void *notused)
 289 {
 290         (void) sched_attach();
 291         p31b_setcfg(CTL_P1003_1B_PAGESIZE, PAGE_SIZE);
 292 }
 293
 294 SYSINIT(p31b, SI_SUB_P1003_1B, SI_ORDER_FIRST, p31binit, NULL);