xref: /titanic_41/usr/src/uts/common/syscall/tasksys.c (revision e4f5a11d4a234623168c1558fcdf4341e11769e1)
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 /*
27  * System calls for creating and inquiring about tasks and projects
28  */
29 
30 #include <sys/param.h>
31 #include <sys/types.h>
32 #include <sys/errno.h>
33 #include <sys/thread.h>
34 #include <sys/proc.h>
35 #include <sys/task.h>
36 #include <sys/systm.h>
37 #include <sys/project.h>
38 #include <sys/cpuvar.h>
39 #include <sys/policy.h>
40 #include <sys/zone.h>
41 #include <sys/rctl.h>
42 
43 /*
44  * Limit projlist to 256k projects.
45  */
46 #define	MAX_PROJLIST_BUFSIZE		1048576
47 
48 typedef struct projlist_walk {
49 	projid_t	*pw_buf;
50 	size_t		pw_bufsz;
51 } projlist_walk_t;
52 
53 /*
54  * taskid_t tasksys_settaskid(projid_t projid, uint_t flags);
55  *
56  * Overview
57  *   Place the calling process in a new task if sufficiently privileged.  If the
58  *   present task is finalized, the process may not create a new task.
59  *
60  * Return values
61  *   0 on success, errno on failure.
62  */
63 static long
64 tasksys_settaskid(projid_t projid, uint_t flags)
65 {
66 	proc_t *p = ttoproc(curthread);
67 	kproject_t *oldpj;
68 	kproject_t *kpj;
69 	task_t *tk, *oldtk;
70 	rctl_entity_p_t e;
71 	zone_t *zone;
72 	int rctlfail = 0;
73 
74 	if (secpolicy_tasksys(CRED()) != 0)
75 		return (set_errno(EPERM));
76 
77 	if (projid < 0 || projid > MAXPROJID)
78 		return (set_errno(EINVAL));
79 
80 	if (flags & ~TASK_FINAL)
81 		return (set_errno(EINVAL));
82 
83 	mutex_enter(&pidlock);
84 	if (p->p_task->tk_flags & TASK_FINAL) {
85 		mutex_exit(&pidlock);
86 		return (set_errno(EACCES));
87 	}
88 	mutex_exit(&pidlock);
89 
90 	/*
91 	 * Try to stop all other lwps in the process while we're changing
92 	 * our project.  This way, curthread doesn't need to grab its own
93 	 * thread_lock to find its project ID (see curprojid()).  If this
94 	 * is the /proc agent lwp, we know that the other lwps are already
95 	 * held.  If we failed to hold all lwps, bail out and return EINTR.
96 	 */
97 	if (curthread != p->p_agenttp && !holdlwps(SHOLDFORK1))
98 		return (set_errno(EINTR));
99 	/*
100 	 * Put a hold on our new project and make sure that nobody is
101 	 * trying to bind it to a pool while we're joining.
102 	 */
103 	kpj = project_hold_by_id(projid, p->p_zone, PROJECT_HOLD_INSERT);
104 	e.rcep_p.proj = kpj;
105 	e.rcep_t = RCENTITY_PROJECT;
106 
107 	mutex_enter(&p->p_lock);
108 	oldpj = p->p_task->tk_proj;
109 	zone = p->p_zone;
110 
111 	mutex_enter(&zone->zone_nlwps_lock);
112 	mutex_enter(&zone->zone_mem_lock);
113 
114 	if (kpj->kpj_nlwps + p->p_lwpcnt > kpj->kpj_nlwps_ctl)
115 		if (rctl_test_entity(rc_project_nlwps, kpj->kpj_rctls, p, &e,
116 		    p->p_lwpcnt, 0) & RCT_DENY)
117 			rctlfail = 1;
118 
119 	if (kpj->kpj_ntasks + 1 > kpj->kpj_ntasks_ctl)
120 		if (rctl_test_entity(rc_project_ntasks, kpj->kpj_rctls, p, &e,
121 		    1, 0) & RCT_DENY)
122 			rctlfail = 1;
123 
124 	if (kpj != proj0p && kpj->kpj_nprocs + 1 > kpj->kpj_nprocs_ctl)
125 		if (rctl_test_entity(rc_project_nprocs, kpj->kpj_rctls, p, &e,
126 		    1, 0) & RCT_DENY)
127 			rctlfail = 1;
128 
129 	if (kpj->kpj_data.kpd_locked_mem + p->p_locked_mem >
130 	    kpj->kpj_data.kpd_locked_mem_ctl)
131 		if (rctl_test_entity(rc_project_locked_mem, kpj->kpj_rctls, p,
132 		    &e, p->p_locked_mem, 0) & RCT_DENY)
133 			rctlfail = 1;
134 
135 	mutex_enter(&(kpj->kpj_data.kpd_crypto_lock));
136 	if (kpj->kpj_data.kpd_crypto_mem + p->p_crypto_mem >
137 	    kpj->kpj_data.kpd_crypto_mem_ctl)
138 		if (rctl_test_entity(rc_project_crypto_mem, kpj->kpj_rctls, p,
139 		    &e, p->p_crypto_mem, 0) & RCT_DENY)
140 			rctlfail = 1;
141 
142 	if (rctlfail) {
143 		mutex_exit(&(kpj->kpj_data.kpd_crypto_lock));
144 		mutex_exit(&zone->zone_mem_lock);
145 		mutex_exit(&zone->zone_nlwps_lock);
146 		if (curthread != p->p_agenttp)
147 			continuelwps(p);
148 		mutex_exit(&p->p_lock);
149 		return (set_errno(EAGAIN));
150 	}
151 	kpj->kpj_data.kpd_crypto_mem += p->p_crypto_mem;
152 	mutex_exit(&(kpj->kpj_data.kpd_crypto_lock));
153 	kpj->kpj_data.kpd_locked_mem += p->p_locked_mem;
154 	kpj->kpj_nlwps += p->p_lwpcnt;
155 	kpj->kpj_ntasks++;
156 	kpj->kpj_nprocs++;
157 
158 	oldpj->kpj_data.kpd_locked_mem -= p->p_locked_mem;
159 	mutex_enter(&(oldpj->kpj_data.kpd_crypto_lock));
160 	oldpj->kpj_data.kpd_crypto_mem -= p->p_crypto_mem;
161 	mutex_exit(&(oldpj->kpj_data.kpd_crypto_lock));
162 	oldpj->kpj_nlwps -= p->p_lwpcnt;
163 	oldpj->kpj_nprocs--;
164 
165 	mutex_exit(&zone->zone_mem_lock);
166 	mutex_exit(&zone->zone_nlwps_lock);
167 	mutex_exit(&p->p_lock);
168 
169 	mutex_enter(&kpj->kpj_poolbind);
170 	tk = task_create(projid, curproc->p_zone);
171 	mutex_enter(&cpu_lock);
172 	/*
173 	 * Returns with p_lock held.
174 	 */
175 	oldtk = task_join(tk, flags);
176 	if (curthread != p->p_agenttp)
177 		continuelwps(p);
178 	mutex_exit(&p->p_lock);
179 	mutex_exit(&cpu_lock);
180 	mutex_exit(&kpj->kpj_poolbind);
181 	task_rele(oldtk);
182 	project_rele(kpj);
183 	return (tk->tk_tkid);
184 }
185 
186 /*
187  * taskid_t tasksys_gettaskid(void);
188  *
189  * Overview
190  *   Return the current task ID for this process.
191  *
192  * Return value
193  *   The ID for the task to which the current process belongs.
194  */
195 static long
196 tasksys_gettaskid()
197 {
198 	long ret;
199 	proc_t *p = ttoproc(curthread);
200 
201 	mutex_enter(&pidlock);
202 	ret = p->p_task->tk_tkid;
203 	mutex_exit(&pidlock);
204 	return (ret);
205 }
206 
207 /*
208  * projid_t tasksys_getprojid(void);
209  *
210  * Overview
211  *   Return the current project ID for this process.
212  *
213  * Return value
214  *   The ID for the project to which the current process belongs.
215  */
216 static long
217 tasksys_getprojid()
218 {
219 	long ret;
220 	proc_t *p = ttoproc(curthread);
221 
222 	mutex_enter(&pidlock);
223 	ret = p->p_task->tk_proj->kpj_id;
224 	mutex_exit(&pidlock);
225 	return (ret);
226 }
227 
228 static int
229 tasksys_projlist_cb(kproject_t *kp, void *buf)
230 {
231 	projlist_walk_t *pw = (projlist_walk_t *)buf;
232 
233 	if (pw && pw->pw_bufsz >= sizeof (projid_t)) {
234 		*pw->pw_buf = kp->kpj_id;
235 		pw->pw_buf++;
236 		pw->pw_bufsz -= sizeof (projid_t);
237 	}
238 
239 	return (0);
240 }
241 
242 /*
243  * long tasksys_projlist(void *buf, size_t bufsz)
244  *
245  * Overview
246  *   Return a buffer containing the project IDs of all currently active projects
247  *   in the current zone.
248  *
249  * Return values
250  *   The minimum size of a buffer sufficiently large to contain all of the
251  *   active project IDs, or -1 if an error occurs during copyout.
252  */
253 static long
254 tasksys_projlist(void *buf, size_t bufsz)
255 {
256 	long ret = 0;
257 	projlist_walk_t pw;
258 	void *kbuf;
259 
260 	if (buf == NULL || bufsz == 0)
261 		return (project_walk_all(getzoneid(), tasksys_projlist_cb,
262 		    NULL));
263 
264 	if (bufsz > MAX_PROJLIST_BUFSIZE)
265 		return (set_errno(ENOMEM));
266 
267 	kbuf = pw.pw_buf = kmem_zalloc(bufsz, KM_SLEEP);
268 	pw.pw_bufsz = bufsz;
269 
270 	ret = project_walk_all(getzoneid(), tasksys_projlist_cb, &pw);
271 
272 	if (copyout(kbuf, buf, bufsz) == -1)
273 		ret = set_errno(EFAULT);
274 
275 	kmem_free(kbuf, bufsz);
276 	return (ret);
277 }
278 
279 long
280 tasksys(int code, projid_t projid, uint_t flags, void *projidbuf, size_t pbufsz)
281 {
282 	switch (code) {
283 	case 0:
284 		return (tasksys_settaskid(projid, flags));
285 	case 1:
286 		return (tasksys_gettaskid());
287 	case 2:
288 		return (tasksys_getprojid());
289 	case 3:
290 		return (tasksys_projlist(projidbuf, pbufsz));
291 	default:
292 		return (set_errno(EINVAL));
293 	}
294 }
295