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 #include <sys/unistd.h>
  50
  51 #include <sys/mplock2.h>
  52
  53 MALLOC_DEFINE(M_P31B, "p1003.1b", "Posix 1003.1B");
  54
  55 /* p31b_proc: Return a proc struct corresponding to a pid to operate on.
  56  *
  57  * Enforce permission policy.
  58  *
  59  * The policy is the same as for sending signals except there
  60  * is no notion of process groups.
  61  *
  62  * pid == 0 means my process.
  63  *
  64  * This is disabled until I've got a permission gate in again:
  65  * only root can do this.
  66  */
  67
  68 #if 0
  69 /*
  70  * This is stolen from CANSIGNAL in kern_sig:
  71  *
  72  * Can process p, with pcred pc, do "write flavor" operations to process q?
  73  */
  74 #define CAN_AFFECT(p, cr, q) \
  75         ((cr)->cr_uid == 0 || \
  76             (cr)->cr_ruid == (q)->p_ucred->cr_ruid || \
  77             (cr)->cr_uid == (q)->p_ucred->cr_ruid || \
  78             (cr)->cr_ruid == (q)->p_ucred->cr_uid || \
  79             (cr)->cr_uid == (q)->p_ucred->cr_uid)
  80 #else
  81 #define CAN_AFFECT(p, cr, q) ((cr)->cr_uid == 0)
  82 #endif
  83
  84 /*
  85  * p31b_proc: Look up a proc from a PID.  If proc is 0 it is
  86  * my own proc.
  87  */
  88 int p31b_proc(struct proc *p, pid_t pid, struct proc **pp)
  89 {
  90         int ret = 0;
  91         struct proc *other_proc = 0;
  92
  93         if (pid == 0)
  94                 other_proc = p;
  95         else
  96                 other_proc = pfind(pid);
  97
  98         if (other_proc)
  99         {
 100                 /* Enforce permission policy.
 101                  */
 102                 if (CAN_AFFECT(p, p->p_ucred, other_proc))
 103                         *pp = other_proc;
 104                 else
 105                         ret = EPERM;
 106         }
 107         else
 108                 ret = ESRCH;
 109
 110         return ret;
 111 }
 112
 113
 114 #if !defined(_KPOSIX_PRIORITY_SCHEDULING)
 115
 116 int syscall_not_present(const char *s);
 117
 118 /* The system calls return ENOSYS if an entry is called that is
 119  * not run-time supported.  I am also logging since some programs
 120  * start to use this when they shouldn't.  That will be removed if annoying.
 121  */
 122 int syscall_not_present(const char *s)
 123 {
 124         struct proc *p = curproc;
 125         log(LOG_ERR, "cmd %s pid %d tried to use non-present %s\n",
 126                         p->p_comm, p->p_pid, s);
 127
 128         /* a " return nosys(p, uap); " here causes a core dump.
 129          */
 130
 131         return ENOSYS;
 132 }
 133
 134 /* Not configured but loadable via a module:
 135  */
 136
 137 static int sched_attach(void)
 138 {
 139         return 0;
 140 }
 141
 142 #define SYSCALL_NOT_PRESENT_GEN(SC) \
 143 int SC (struct SC##_args *uap) \
 144 { \
 145         return syscall_not_present(#SC); \
 146 }
 147
 148 SYSCALL_NOT_PRESENT_GEN(sched_setparam)
 149 SYSCALL_NOT_PRESENT_GEN(sched_getparam)
 150 SYSCALL_NOT_PRESENT_GEN(sched_setscheduler)
 151 SYSCALL_NOT_PRESENT_GEN(sched_getscheduler)
 152 SYSCALL_NOT_PRESENT_GEN(sched_yield)
 153 SYSCALL_NOT_PRESENT_GEN(sched_get_priority_max)
 154 SYSCALL_NOT_PRESENT_GEN(sched_get_priority_min)
 155 SYSCALL_NOT_PRESENT_GEN(sched_rr_get_interval)
 156
 157 #else
 158
 159 /* Configured in kernel version:
 160  */
 161 static struct ksched *ksched;
 162
 163 static int sched_attach(void)
 164 {
 165         int ret = ksched_attach(&ksched);
 166
 167         if (ret == 0)
 168                 p31b_setcfg(CTL_P1003_1B_PRIORITY_SCHEDULING, 1);
 169
 170         return ret;
 171 }
 172
 173 /*
 174  * MPALMOSTSAFE
 175  */
 176 int
 177 sys_sched_setparam(struct sched_setparam_args *uap)
 178 {
 179         struct proc *p = curproc;
 180         struct lwp *lp;
 181         int e;
 182         struct sched_param sched_param;
 183
 184         copyin(uap->param, &sched_param, sizeof(sched_param));
 185
 186         get_mplock();
 187         if ((e = p31b_proc(p, uap->pid, &p)) == 0) {
 188                 lp = FIRST_LWP_IN_PROC(p); /* XXX lwp */
 189                 e = ksched_setparam(&uap->sysmsg_reg, ksched, lp,
 190                                     (const struct sched_param *)&sched_param);
 191         }
 192         rel_mplock();
 193         return e;
 194 }
 195
 196 /*
 197  * MPALMOSTSAFE
 198  */
 199 int
 200 sys_sched_getparam(struct sched_getparam_args *uap)
 201 {
 202         struct proc *p = curproc;
 203         struct proc *targetp;
 204         struct lwp *lp;
 205         struct sched_param sched_param;
 206         int e;
 207
 208         get_mplock();
 209         if (uap->pid != 0 && uap->pid != p->p_pid) {
 210                 e = p31b_proc(p, uap->pid, &targetp);
 211                 if (e)
 212                         goto done;
 213         } else {
 214                 targetp = p;
 215         }
 216
 217         lp = FIRST_LWP_IN_PROC(targetp); /* XXX lwp */
 218         e = ksched_getparam(&uap->sysmsg_reg, ksched, lp, &sched_param);
 219 done:
 220         rel_mplock();
 221         if (e == 0)
 222                 copyout(&sched_param, uap->param, sizeof(sched_param));
 223         return e;
 224 }
 225
 226 /*
 227  * MPALMOSTSAFE
 228  */
 229 int
 230 sys_sched_setscheduler(struct sched_setscheduler_args *uap)
 231 {
 232         struct proc *p = curproc;
 233         struct lwp *lp;
 234         int e;
 235         struct sched_param sched_param;
 236
 237         copyin(uap->param, &sched_param, sizeof(sched_param));
 238
 239         get_mplock();
 240         if ((e = p31b_proc(p, uap->pid, &p)) == 0) {
 241                 lp = FIRST_LWP_IN_PROC(p); /* XXX lwp */
 242                 e = ksched_setscheduler(&uap->sysmsg_reg, ksched, lp,
 243                                         uap->policy,
 244                                     (const struct sched_param *)&sched_param);
 245         }
 246         rel_mplock();
 247         return e;
 248 }
 249
 250 /*
 251  * MPALMOSTSAFE
 252  */
 253 int
 254 sys_sched_getscheduler(struct sched_getscheduler_args *uap)
 255 {
 256         struct proc *p = curproc;
 257         struct proc *targetp;
 258         struct lwp *lp;
 259         int e;
 260
 261         get_mplock();
 262         if (uap->pid != 0 && uap->pid != p->p_pid) {
 263                 e = p31b_proc(p, uap->pid, &targetp);
 264                 if (e)
 265                         goto done;
 266         } else {
 267                 targetp = p;
 268         }
 269
 270         lp = FIRST_LWP_IN_PROC(targetp); /* XXX lwp */
 271         e = ksched_getscheduler(&uap->sysmsg_reg, ksched, lp);
 272 done:
 273         rel_mplock();
 274         return e;
 275 }
 276
 277 /*
 278  * MPSAFE
 279  */
 280 int
 281 sys_sched_yield(struct sched_yield_args *uap)
 282 {
 283         return ksched_yield(&uap->sysmsg_reg, ksched);
 284 }
 285
 286 /*
 287  * MPSAFE
 288  */
 289 int
 290 sys_sched_get_priority_max(struct sched_get_priority_max_args *uap)
 291 {
 292         return ksched_get_priority_max(&uap->sysmsg_reg, ksched, uap->policy);
 293 }
 294
 295 /*
 296  * MPSAFE
 297  */
 298 int
 299 sys_sched_get_priority_min(struct sched_get_priority_min_args *uap)
 300 {
 301         return ksched_get_priority_min(&uap->sysmsg_reg, ksched, uap->policy);
 302 }
 303
 304 /*
 305  * MPALMOSTSAFE
 306  */
 307 int
 308 sys_sched_rr_get_interval(struct sched_rr_get_interval_args *uap)
 309 {
 310         int e;
 311         struct proc *p = curproc;
 312         struct lwp *lp = curthread->td_lwp;
 313
 314         get_mplock();
 315         if ((e = p31b_proc(p, uap->pid, &p)) == 0) {
 316                 e = ksched_rr_get_interval(&uap->sysmsg_reg, ksched,
 317                                            lp, uap->interval);
 318         }
 319         rel_mplock();
 320         return e;
 321 }
 322
 323 #endif
 324
 325 static void
 326 p31binit(void *notused)
 327 {
 328         (void) sched_attach();
 329         p31b_setcfg(CTL_P1003_1B_PAGESIZE, PAGE_SIZE);
 330         p31b_setcfg(CTL_P1003_1B_ASYNCHRONOUS_IO, -1);
 331         p31b_setcfg(CTL_P1003_1B_MESSAGE_PASSING, _POSIX_MESSAGE_PASSING);
 332 }
 333
 334 SYSINIT(p31b, SI_SUB_P1003_1B, SI_ORDER_FIRST, p31binit, NULL);