kernel/syscall/tasksys.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
  23  */
  24
  25 /*
  26  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  27  */
  28
  29 /*
  30  * System calls for creating and inquiring about tasks and projects
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/types.h>
  35 #include <sys/errno.h>
  36 #include <sys/thread.h>
  37 #include <sys/proc.h>
  38 #include <sys/task.h>
  39 #include <sys/systm.h>
  40 #include <sys/project.h>
  41 #include <sys/cpuvar.h>
  42 #include <sys/policy.h>
  43 #include <sys/zone.h>
  44 #include <sys/rctl.h>
  45
  46 /*
  47  * Limit projlist to 256k projects.
  48  */
  49 #define MAX_PROJLIST_BUFSIZE            1048576
  50
  51 typedef struct projlist_walk {
  52         projid_t        *pw_buf;
  53         size_t          pw_bufsz;
  54 } projlist_walk_t;
  55
  56 /*
  57  * taskid_t tasksys_settaskid(projid_t projid, uint_t flags);
  58  *
  59  * Overview
  60  *   Place the calling process in a new task if sufficiently privileged.  If the
  61  *   present task is finalized, the process may not create a new task.
  62  *
  63  * Return values
  64  *   0 on success, errno on failure.
  65  */
  66 static long
  67 tasksys_settaskid(projid_t projid, uint_t flags)
  68 {
  69         proc_t *p = ttoproc(curthread);
  70         kproject_t *oldpj;
  71         kproject_t *kpj;
  72         task_t *tk, *oldtk;
  73         rctl_entity_p_t e;
  74         zone_t *zone;
  75         int rctlfail = 0;
  76
  77         if (secpolicy_tasksys(CRED()) != 0)
  78                 return (set_errno(EPERM));
  79
  80         if (projid < 0 || projid > MAXPROJID)
  81                 return (set_errno(EINVAL));
  82
  83         if (flags & ~TASK_FINAL)
  84                 return (set_errno(EINVAL));
  85
  86         mutex_enter(&pidlock);
  87         if (p->p_task->tk_flags & TASK_FINAL) {
  88                 mutex_exit(&pidlock);
  89                 return (set_errno(EACCES));
  90         }
  91         mutex_exit(&pidlock);
  92
  93         /*
  94          * Try to stop all other lwps in the process while we're changing
  95          * our project.  This way, curthread doesn't need to grab its own
  96          * thread_lock to find its project ID (see curprojid()).  If this
  97          * is the /proc agent lwp, we know that the other lwps are already
  98          * held.  If we failed to hold all lwps, bail out and return EINTR.
  99          */
 100         if (curthread != p->p_agenttp && !holdlwps(SHOLDFORK1))
 101                 return (set_errno(EINTR));
 102         /*
 103          * Put a hold on our new project and make sure that nobody is
 104          * trying to bind it to a pool while we're joining.
 105          */
 106         kpj = project_hold_by_id(projid, p->p_zone, PROJECT_HOLD_INSERT);
 107         e.rcep_p.proj = kpj;
 108         e.rcep_t = RCENTITY_PROJECT;
 109
 110         mutex_enter(&p->p_lock);
 111         oldpj = p->p_task->tk_proj;
 112         zone = p->p_zone;
 113
 114         mutex_enter(&zone->zone_nlwps_lock);
 115         mutex_enter(&zone->zone_mem_lock);
 116
 117         if (kpj->kpj_nlwps + p->p_lwpcnt > kpj->kpj_nlwps_ctl)
 118                 if (rctl_test_entity(rc_project_nlwps, kpj->kpj_rctls, p, &e,
 119                     p->p_lwpcnt, 0) & RCT_DENY)
 120                         rctlfail = 1;
 121
 122         if (kpj->kpj_ntasks + 1 > kpj->kpj_ntasks_ctl)
 123                 if (rctl_test_entity(rc_project_ntasks, kpj->kpj_rctls, p, &e,
 124                     1, 0) & RCT_DENY)
 125                         rctlfail = 1;
 126
 127         if (kpj != proj0p && kpj->kpj_nprocs + 1 > kpj->kpj_nprocs_ctl)
 128                 if (rctl_test_entity(rc_project_nprocs, kpj->kpj_rctls, p, &e,
 129                     1, 0) & RCT_DENY)
 130                         rctlfail = 1;
 131
 132         if (kpj->kpj_data.kpd_locked_mem + p->p_locked_mem >
 133             kpj->kpj_data.kpd_locked_mem_ctl)
 134                 if (rctl_test_entity(rc_project_locked_mem, kpj->kpj_rctls, p,
 135                     &e, p->p_locked_mem, 0) & RCT_DENY)
 136                         rctlfail = 1;
 137
 138         mutex_enter(&(kpj->kpj_data.kpd_crypto_lock));
 139         if (kpj->kpj_data.kpd_crypto_mem + p->p_crypto_mem >
 140             kpj->kpj_data.kpd_crypto_mem_ctl)
 141                 if (rctl_test_entity(rc_project_crypto_mem, kpj->kpj_rctls, p,
 142                     &e, p->p_crypto_mem, 0) & RCT_DENY)
 143                         rctlfail = 1;
 144
 145         if (rctlfail) {
 146                 mutex_exit(&(kpj->kpj_data.kpd_crypto_lock));
 147                 mutex_exit(&zone->zone_mem_lock);
 148                 mutex_exit(&zone->zone_nlwps_lock);
 149                 if (curthread != p->p_agenttp)
 150                         continuelwps(p);
 151                 mutex_exit(&p->p_lock);
 152                 project_rele(kpj);
 153                 return (set_errno(EAGAIN));
 154         }
 155         kpj->kpj_data.kpd_crypto_mem += p->p_crypto_mem;
 156         mutex_exit(&(kpj->kpj_data.kpd_crypto_lock));
 157         kpj->kpj_data.kpd_locked_mem += p->p_locked_mem;
 158         kpj->kpj_nlwps += p->p_lwpcnt;
 159         kpj->kpj_ntasks++;
 160         kpj->kpj_nprocs++;
 161
 162         oldpj->kpj_data.kpd_locked_mem -= p->p_locked_mem;
 163         mutex_enter(&(oldpj->kpj_data.kpd_crypto_lock));
 164         oldpj->kpj_data.kpd_crypto_mem -= p->p_crypto_mem;
 165         mutex_exit(&(oldpj->kpj_data.kpd_crypto_lock));
 166         oldpj->kpj_nlwps -= p->p_lwpcnt;
 167         oldpj->kpj_nprocs--;
 168
 169         mutex_exit(&zone->zone_mem_lock);
 170         mutex_exit(&zone->zone_nlwps_lock);
 171         mutex_exit(&p->p_lock);
 172
 173         mutex_enter(&kpj->kpj_poolbind);
 174         tk = task_create(projid, curproc->p_zone);
 175         mutex_enter(&cpu_lock);
 176         /*
 177          * Returns with p_lock held.
 178          */
 179         oldtk = task_join(tk, flags);
 180         if (curthread != p->p_agenttp)
 181                 continuelwps(p);
 182         mutex_exit(&p->p_lock);
 183         mutex_exit(&cpu_lock);
 184         mutex_exit(&kpj->kpj_poolbind);
 185         task_rele(oldtk);
 186         project_rele(kpj);
 187         return (tk->tk_tkid);
 188 }
 189
 190 /*
 191  * taskid_t tasksys_gettaskid(void);
 192  *
 193  * Overview
 194  *   Return the current task ID for this process.
 195  *
 196  * Return value
 197  *   The ID for the task to which the current process belongs.
 198  */
 199 static long
 200 tasksys_gettaskid()
 201 {
 202         long ret;
 203         proc_t *p = ttoproc(curthread);
 204
 205         mutex_enter(&pidlock);
 206         ret = p->p_task->tk_tkid;
 207         mutex_exit(&pidlock);
 208         return (ret);
 209 }
 210
 211 /*
 212  * projid_t tasksys_getprojid(void);
 213  *
 214  * Overview
 215  *   Return the current project ID for this process.
 216  *
 217  * Return value
 218  *   The ID for the project to which the current process belongs.
 219  */
 220 static long
 221 tasksys_getprojid()
 222 {
 223         long ret;
 224         proc_t *p = ttoproc(curthread);
 225
 226         mutex_enter(&pidlock);
 227         ret = p->p_task->tk_proj->kpj_id;
 228         mutex_exit(&pidlock);
 229         return (ret);
 230 }
 231
 232 static int
 233 tasksys_projlist_cb(kproject_t *kp, void *buf)
 234 {
 235         projlist_walk_t *pw = (projlist_walk_t *)buf;
 236
 237         if (pw && pw->pw_bufsz >= sizeof (projid_t)) {
 238                 *pw->pw_buf = kp->kpj_id;
 239                 pw->pw_buf++;
 240                 pw->pw_bufsz -= sizeof (projid_t);
 241         }
 242
 243         return (0);
 244 }
 245
 246 /*
 247  * long tasksys_projlist(void *buf, size_t bufsz)
 248  *
 249  * Overview
 250  *   Return a buffer containing the project IDs of all currently active projects
 251  *   in the current zone.
 252  *
 253  * Return values
 254  *   The minimum size of a buffer sufficiently large to contain all of the
 255  *   active project IDs, or -1 if an error occurs during copyout.
 256  */
 257 static long
 258 tasksys_projlist(void *buf, size_t bufsz)
 259 {
 260         long ret = 0;
 261         projlist_walk_t pw;
 262         void *kbuf;
 263
 264         if (buf == NULL || bufsz == 0)
 265                 return (project_walk_all(getzoneid(), tasksys_projlist_cb,
 266                     NULL));
 267
 268         if (bufsz > MAX_PROJLIST_BUFSIZE)
 269                 return (set_errno(ENOMEM));
 270
 271         kbuf = pw.pw_buf = kmem_zalloc(bufsz, KM_SLEEP);
 272         pw.pw_bufsz = bufsz;
 273
 274         ret = project_walk_all(getzoneid(), tasksys_projlist_cb, &pw);
 275
 276         if (copyout(kbuf, buf, bufsz) == -1)
 277                 ret = set_errno(EFAULT);
 278
 279         kmem_free(kbuf, bufsz);
 280         return (ret);
 281 }
 282
 283 long
 284 tasksys(int code, projid_t projid, uint_t flags, void *projidbuf, size_t pbufsz)
 285 {
 286         switch (code) {
 287         case 0:
 288                 return (tasksys_settaskid(projid, flags));
 289         case 1:
 290                 return (tasksys_gettaskid());
 291         case 2:
 292                 return (tasksys_getprojid());
 293         case 3:
 294                 return (tasksys_projlist(projidbuf, pbufsz));
 295         default:
 296                 return (set_errno(EINVAL));
 297         }
 298 }