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  */
  34
  35 /* p1003_1b: Real Time common code.
  36  */
  37
  38 #include <sys/param.h>
  39 #include <sys/systm.h>
  40 #include <sys/kernel.h>
  41 #include <sys/sysent.h>
  42 #include <sys/posix4.h>
  43 #include <sys/proc.h>
  44 #include <sys/syslog.h>
  45 #include <sys/module.h>
  46 #include <sys/sysproto.h>
  47 #include <sys/sysctl.h>
  48 #include <sys/unistd.h>
  49
  50 MALLOC_DEFINE(M_P31B, "p1003.1b", "Posix 1003.1B");
  51
  52 /*
  53  * p31b_proc: Return a proc struct corresponding to a pid to operate on.
  54  *
  55  * Enforce permission policy.
  56  *
  57  * The policy is the same as for sending signals except there
  58  * is no notion of process groups.
  59  *
  60  * pid == 0 means my process.
  61  *
  62  * This is disabled until I've got a permission gate in again:
  63  * only root can do this.
  64  */
  65
  66 #if 0
  67 /*
  68  * This is stolen from CANSIGNAL in kern_sig:
  69  *
  70  * Can process p, with pcred pc, do "write flavor" operations to process q?
  71  */
  72 #define CAN_AFFECT(p, cr, q) \
  73         ((cr)->cr_uid == 0 || \
  74             (cr)->cr_ruid == (q)->p_ucred->cr_ruid || \
  75             (cr)->cr_uid == (q)->p_ucred->cr_ruid || \
  76             (cr)->cr_ruid == (q)->p_ucred->cr_uid || \
  77             (cr)->cr_uid == (q)->p_ucred->cr_uid)
  78 #else
  79 #define CAN_AFFECT(p, cr, q) ((cr)->cr_uid == 0)
  80 #endif
  81
  82 #if !defined(_KPOSIX_PRIORITY_SCHEDULING)
  83
  84 int syscall_not_present(const char *s);
  85
  86 /* The system calls return ENOSYS if an entry is called that is
  87  * not run-time supported.  I am also logging since some programs
  88  * start to use this when they shouldn't.  That will be removed if annoying.
  89  */
  90 int syscall_not_present(const char *s)
  91 {
  92         struct proc *p = curproc;
  93         log(LOG_ERR, "cmd %s pid %d tried to use non-present %s\n",
  94                         p->p_comm, p->p_pid, s);
  95
  96         /* a " return nosys(p, uap); " here causes a core dump.
  97          */
  98
  99         return ENOSYS;
 100 }
 101
 102 /* Not configured but loadable via a module:
 103  */
 104
 105 static int sched_attach(void)
 106 {
 107         return 0;
 108 }
 109
 110 #define SYSCALL_NOT_PRESENT_GEN(SC) \
 111 int sys_##SC (struct SC##_args *uap) \
 112 { \
 113         return syscall_not_present(#SC); \
 114 }
 115
 116 SYSCALL_NOT_PRESENT_GEN(sched_setparam)
 117 SYSCALL_NOT_PRESENT_GEN(sched_getparam)
 118 SYSCALL_NOT_PRESENT_GEN(sched_setscheduler)
 119 SYSCALL_NOT_PRESENT_GEN(sched_getscheduler)
 120 SYSCALL_NOT_PRESENT_GEN(sched_yield)
 121 SYSCALL_NOT_PRESENT_GEN(sched_get_priority_max)
 122 SYSCALL_NOT_PRESENT_GEN(sched_get_priority_min)
 123 SYSCALL_NOT_PRESENT_GEN(sched_rr_get_interval)
 124
 125 #else
 126
 127 /*
 128  * p31b_proc: Look up a proc from a PID.  If proc is 0 it is
 129  * my own proc.
 130  *
 131  * Returns a held process in *pp.
 132  */
 133 static
 134 int
 135 p31b_proc(pid_t pid, struct proc **pp)
 136 {
 137         int ret = 0;
 138         struct proc *p = curproc;
 139         struct proc *other_proc;
 140
 141         if (pid == 0) {
 142                 other_proc = p;
 143                 if (other_proc)
 144                         PHOLD(other_proc);
 145         } else {
 146                 other_proc = pfind(pid);
 147                 /* ref from pfind() */
 148         }
 149
 150         if (other_proc) {
 151                 /* Enforce permission policy.
 152                  */
 153                 if (CAN_AFFECT(p, p->p_ucred, other_proc)) {
 154                         *pp = other_proc;
 155                         lwkt_gettoken(&other_proc->p_token);
 156                 } else {
 157                         *pp = NULL;
 158                         ret = EPERM;
 159                         PRELE(other_proc);
 160                 }
 161         } else {
 162                 *pp = NULL;
 163                 ret = ESRCH;
 164         }
 165         return ret;
 166 }
 167
 168 static
 169 void
 170 p31b_proc_done(struct proc *other_proc)
 171 {
 172         if (other_proc) {
 173                 lwkt_reltoken(&other_proc->p_token);
 174                 PRELE(other_proc);
 175         }
 176 }
 177
 178 /* Configured in kernel version:
 179  */
 180 static struct ksched *ksched;
 181
 182 static int sched_attach(void)
 183 {
 184         int ret = ksched_attach(&ksched);
 185
 186         if (ret == 0)
 187                 p31b_setcfg(CTL_P1003_1B_PRIORITY_SCHEDULING, 1);
 188
 189         return ret;
 190 }
 191
 192 int
 193 sys_sched_setparam(struct sched_setparam_args *uap)
 194 {
 195         struct proc *p;
 196         struct lwp *lp;
 197         struct sched_param sched_param;
 198         int e;
 199
 200         copyin(uap->param, &sched_param, sizeof(sched_param));
 201
 202         if ((e = p31b_proc(uap->pid, &p)) == 0) {
 203                 lp = FIRST_LWP_IN_PROC(p); /* XXX lwp */
 204                 if (lp) {
 205                         LWPHOLD(lp);
 206                         lwkt_gettoken(&lp->lwp_token);
 207                         e = ksched_setparam(&uap->sysmsg_reg, ksched, lp,
 208                                     (const struct sched_param *)&sched_param);
 209                         lwkt_reltoken(&lp->lwp_token);
 210                         LWPRELE(lp);
 211                 } else {
 212                         e = ESRCH;
 213                 }
 214                 p31b_proc_done(p);
 215         }
 216         return e;
 217 }
 218
 219 int
 220 sys_sched_getparam(struct sched_getparam_args *uap)
 221 {
 222         struct proc *targetp;
 223         struct lwp *lp;
 224         struct sched_param sched_param;
 225         int e;
 226
 227         if ((e = p31b_proc(uap->pid, &targetp)) == 0) {
 228                 lp = FIRST_LWP_IN_PROC(targetp); /* XXX lwp */
 229                 if (lp) {
 230                         LWPHOLD(lp);
 231                         lwkt_gettoken(&lp->lwp_token);
 232                         e = ksched_getparam(&uap->sysmsg_reg, ksched,
 233                                             lp, &sched_param);
 234                         lwkt_reltoken(&lp->lwp_token);
 235                         LWPRELE(lp);
 236                 } else {
 237                         e = ESRCH;
 238                 }
 239                 p31b_proc_done(targetp);
 240         }
 241         if (e == 0)
 242                 copyout(&sched_param, uap->param, sizeof(sched_param));
 243         return e;
 244 }
 245
 246 int
 247 sys_sched_setscheduler(struct sched_setscheduler_args *uap)
 248 {
 249         struct proc *p;
 250         struct lwp *lp;
 251         int e;
 252         struct sched_param sched_param;
 253
 254         copyin(uap->param, &sched_param, sizeof(sched_param));
 255
 256         if ((e = p31b_proc(uap->pid, &p)) == 0) {
 257                 lp = FIRST_LWP_IN_PROC(p); /* XXX lwp */
 258                 if (lp) {
 259                         LWPHOLD(lp);
 260                         lwkt_gettoken(&lp->lwp_token);
 261                         e = ksched_setscheduler(&uap->sysmsg_reg, ksched,
 262                                                 lp, uap->policy,
 263                                     (const struct sched_param *)&sched_param);
 264                         lwkt_reltoken(&lp->lwp_token);
 265                         LWPRELE(lp);
 266                 } else {
 267                         e = ESRCH;
 268                 }
 269                 p31b_proc_done(p);
 270         }
 271         return e;
 272 }
 273
 274 int
 275 sys_sched_getscheduler(struct sched_getscheduler_args *uap)
 276 {
 277         struct proc *targetp;
 278         struct lwp *lp;
 279         int e;
 280
 281         if ((e = p31b_proc(uap->pid, &targetp)) == 0) {
 282                 lp = FIRST_LWP_IN_PROC(targetp); /* XXX lwp */
 283                 if (lp) {
 284                         LWPHOLD(lp);
 285                         lwkt_gettoken(&lp->lwp_token);
 286                         e = ksched_getscheduler(&uap->sysmsg_reg, ksched, lp);
 287                         lwkt_reltoken(&lp->lwp_token);
 288                         LWPRELE(lp);
 289                 } else {
 290                         e = ESRCH;
 291                 }
 292                 p31b_proc_done(targetp);
 293         }
 294         return e;
 295 }
 296
 297 /*
 298  * MPSAFE
 299  */
 300 int
 301 sys_sched_yield(struct sched_yield_args *uap)
 302 {
 303         return ksched_yield(&uap->sysmsg_reg, ksched);
 304 }
 305
 306 /*
 307  * MPSAFE
 308  */
 309 int
 310 sys_sched_get_priority_max(struct sched_get_priority_max_args *uap)
 311 {
 312         return ksched_get_priority_max(&uap->sysmsg_reg, ksched, uap->policy);
 313 }
 314
 315 /*
 316  * MPSAFE
 317  */
 318 int
 319 sys_sched_get_priority_min(struct sched_get_priority_min_args *uap)
 320 {
 321         return ksched_get_priority_min(&uap->sysmsg_reg, ksched, uap->policy);
 322 }
 323
 324 int
 325 sys_sched_rr_get_interval(struct sched_rr_get_interval_args *uap)
 326 {
 327         int e;
 328         struct proc *p;
 329         struct lwp *lp;
 330         struct timespec ts;
 331
 332         if ((e = p31b_proc(uap->pid, &p)) == 0) {
 333                 lp = FIRST_LWP_IN_PROC(p); /* XXX lwp */
 334                 if (lp) {
 335                         LWPHOLD(lp);
 336                         lwkt_gettoken(&lp->lwp_token);
 337                         e = ksched_rr_get_interval(&uap->sysmsg_reg, ksched,
 338                                                    lp, &ts);
 339                         if (e == 0)
 340                                 e = copyout(&ts, uap->interval, sizeof(ts));
 341                         lwkt_reltoken(&lp->lwp_token);
 342                         LWPRELE(lp);
 343                 } else {
 344                         e = ESRCH;
 345                 }
 346                 p31b_proc_done(p);
 347         }
 348         return e;
 349 }
 350
 351 #endif
 352
 353 static void
 354 p31binit(void *notused)
 355 {
 356         sched_attach();
 357         p31b_setcfg(CTL_P1003_1B_ASYNCHRONOUS_IO, -1);
 358         p31b_setcfg(CTL_P1003_1B_MESSAGE_PASSING, _POSIX_MESSAGE_PASSING);
 359         p31b_setcfg(CTL_P1003_1B_PAGESIZE, PAGE_SIZE);
 360         p31b_setcfg(CTL_P1003_1B_SHARED_MEMORY_OBJECTS,
 361             _POSIX_SHARED_MEMORY_OBJECTS);
 362 }
 363
 364 SYSINIT(p31b, SI_SUB_P1003_1B, SI_ORDER_FIRST, p31binit, NULL);