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OS-???? [lx] SIGEV_THREAD_ID emulation needed


   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 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  * Copyright 2015 Joyent, Inc.
  26  */
  27 


  28 #include <errno.h>

  29 #include <string.h>
  30 #include <time.h>
  31 #include <sys/resource.h>
  32 #include <sys/lx_misc.h>
  33 #include <sys/lx_syscall.h>
  34 #include <lx_signum.h>
  35 
  36 /*
  37  * Translating from the Linux clock types to the Illumos types is a bit of a
  38  * mess.
  39  *
  40  * Linux uses different values for it clock identifiers, so we have to do basic
  41  * translations between the two.  Thankfully, both Linux and Illumos implement
  42  * the same POSIX SUSv3 clock types, so the semantics should be identical.
  43  *
  44  * However, CLOCK_REALTIME and CLOCK_HIGHRES (CLOCK_MONOTONIC) are the only two
  45  * clock backends currently implemented on Illumos. Functions in the kernel
  46  * that use the CLOCK_BACKEND macro will return an error for any clock type
  47  * that does not exist in the clock_backend array. These functions are
  48  * clock_settime, clock_gettime, clock_getres and timer_create.


  90 #define LX_CLOCK_MAX    (sizeof (ltos_clock) / sizeof (ltos_clock[0]))
  91 #define LX_TIMER_MAX    (sizeof (ltos_timer) / sizeof (ltos_timer[0]))
  92 
  93 #define LX_SIGEV_PAD_SIZE       ((64 - \
  94         (sizeof (int) * 2 + sizeof (union sigval))) / sizeof (int))
  95 
  96 typedef struct {
  97         union sigval    lx_sigev_value; /* same layout for both */
  98         int             lx_sigev_signo;
  99         int             lx_sigev_notify;
 100         union {
 101                 int     lx_pad[LX_SIGEV_PAD_SIZE];
 102                 int     lx_tid;
 103                 struct {
 104                         void (*lx_notify_function)(union sigval);
 105                         void *lx_notify_attribute;
 106                 } lx_sigev_thread;
 107         } lx_sigev_un;
 108 } lx_sigevent_t;
 109 


 110 /* sigevent sigev_notify conversion table */
 111 static int ltos_sigev[] = {
 112         SIGEV_SIGNAL,
 113         SIGEV_NONE,
 114         SIGEV_THREAD,
 115         0,              /* Linux skips event 3 */
 116         SIGEV_THREAD    /* the Linux SIGEV_THREAD_ID */
 117 };
 118 
 119 #define LX_SIGEV_MAX    (sizeof (ltos_sigev) / sizeof (ltos_sigev[0]))

 120 
 121 long
 122 lx_clock_nanosleep(int clock, int flags, struct timespec *rqtp,
 123     struct timespec *rmtp)
 124 {
 125         int ret = 0;
 126         int err;
 127         struct timespec rqt, rmt;
 128 
 129         if (clock < 0 || clock >= LX_CLOCK_MAX)
 130                 return (-EINVAL);
 131 
 132         if (uucopy(rqtp, &rqt, sizeof (struct timespec)) < 0)
 133                 return (-EFAULT);
 134 
 135         /* the TIMER_RELTIME and TIMER_ABSTIME flags are the same on Linux */
 136         if ((err = clock_nanosleep(ltos_clock[clock], flags, &rqt, &rmt))
 137             != 0) {
 138                 if (err != EINTR)
 139                         return (-err);


 146 
 147         /*
 148          * Only copy values to rmtp if the timer is TIMER_RELTIME and rmtp is
 149          * non-NULL.
 150          */
 151         if (((flags & TIMER_RELTIME) == TIMER_RELTIME) && (rmtp != NULL) &&
 152             (uucopy(&rmt, rmtp, sizeof (struct timespec)) < 0))
 153                 return (-EFAULT);
 154 
 155         return (ret);
 156 }
 157 
 158 /*ARGSUSED*/
 159 long
 160 lx_adjtimex(void *tp)
 161 {
 162         return (-EPERM);
 163 }
 164 
 165 /*
















 166  * The Illumos timer_create man page says it accepts the following clocks:
 167  *   CLOCK_REALTIME (3) wall clock
 168  *   CLOCK_VIRTUAL (1)  user CPU usage clock - No Backend
 169  *   CLOCK_PROF (2)     user and system CPU usage clock - No Backend
 170  *   CLOCK_HIGHRES (4)  non-adjustable, high-resolution clock
 171  * However, in reality the Illumos timer_create only accepts CLOCK_REALTIME
 172  * and CLOCK_HIGHRES, and since we can't use CLOCK_HIGHRES in a zone, we're
 173  * down to one clock.
 174  */
 175 long
 176 lx_timer_create(int clock, struct sigevent *lx_sevp, timer_t *tid)
 177 {
 178         lx_sigevent_t lev;
 179         struct sigevent sev;
 180 
 181         if (clock < 0 || clock >= LX_TIMER_MAX)
 182                 return (-EINVAL);
 183 
 184         /* We have to convert the Linux sigevent layout to the Illumos layout */
 185         if (uucopy(lx_sevp, &lev, sizeof (lev)) < 0)
 186                 return (-EFAULT);
 187 
 188         if (lev.lx_sigev_notify < 0 || lev.lx_sigev_notify > LX_SIGEV_MAX)
 189                 return (-EINVAL);
 190 
 191         sev.sigev_notify = ltos_sigev[lev.lx_sigev_notify];
 192         sev.sigev_signo = ltos_signo[lev.lx_sigev_signo];
 193         sev.sigev_value = lev.lx_sigev_value;
 194 
 195         /*
 196          * The sigevent sigev_notify_function and sigev_notify_attributes
 197          * members are not used by timer_create, so no conversion is needed.
 198          */

 199 

















 200         return ((timer_create(ltos_timer[clock], &sev, tid) < 0) ? -errno : 0);
 201 }
 202 
 203 long
 204 lx_timer_settime(timer_t tid, int flags, struct itimerspec *new_val,
 205     struct itimerspec *old_val)
 206 {
 207         return ((timer_settime(tid, flags, new_val, old_val) < 0) ? -errno : 0);
 208 }
 209 
 210 long
 211 lx_timer_gettime(timer_t tid, struct itimerspec *val)
 212 {
 213         return ((timer_gettime(tid, val) < 0) ? -errno : 0);
 214 }
 215 
 216 long
 217 lx_timer_getoverrun(timer_t tid)
 218 {
 219         int val;


   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 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  * Copyright 2015 Joyent, Inc.
  26  */
  27 
  28 #include <sys/syscall.h>
  29 
  30 #include <errno.h>
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <time.h>
  34 #include <sys/resource.h>
  35 #include <sys/lx_misc.h>
  36 #include <sys/lx_syscall.h>
  37 #include <lx_signum.h>
  38 
  39 /*
  40  * Translating from the Linux clock types to the Illumos types is a bit of a
  41  * mess.
  42  *
  43  * Linux uses different values for it clock identifiers, so we have to do basic
  44  * translations between the two.  Thankfully, both Linux and Illumos implement
  45  * the same POSIX SUSv3 clock types, so the semantics should be identical.
  46  *
  47  * However, CLOCK_REALTIME and CLOCK_HIGHRES (CLOCK_MONOTONIC) are the only two
  48  * clock backends currently implemented on Illumos. Functions in the kernel
  49  * that use the CLOCK_BACKEND macro will return an error for any clock type
  50  * that does not exist in the clock_backend array. These functions are
  51  * clock_settime, clock_gettime, clock_getres and timer_create.


  93 #define LX_CLOCK_MAX    (sizeof (ltos_clock) / sizeof (ltos_clock[0]))
  94 #define LX_TIMER_MAX    (sizeof (ltos_timer) / sizeof (ltos_timer[0]))
  95 
  96 #define LX_SIGEV_PAD_SIZE       ((64 - \
  97         (sizeof (int) * 2 + sizeof (union sigval))) / sizeof (int))
  98 
  99 typedef struct {
 100         union sigval    lx_sigev_value; /* same layout for both */
 101         int             lx_sigev_signo;
 102         int             lx_sigev_notify;
 103         union {
 104                 int     lx_pad[LX_SIGEV_PAD_SIZE];
 105                 int     lx_tid;
 106                 struct {
 107                         void (*lx_notify_function)(union sigval);
 108                         void *lx_notify_attribute;
 109                 } lx_sigev_thread;
 110         } lx_sigev_un;
 111 } lx_sigevent_t;
 112 
 113 #define lx_sigev_notify_attributes      lx_sigev_un.lx_sigev_thread.lx_notify_attribute
 114 
 115 /* sigevent sigev_notify conversion table */
 116 static int ltos_sigev[] = {
 117         SIGEV_SIGNAL,
 118         SIGEV_NONE,
 119         SIGEV_THREAD,
 120         0,              /* Linux skips event 3 */
 121         SIGEV_THREAD    /* Linux SIGEV_THREAD_ID -- see lx_sigev_thread_id() */
 122 };
 123 
 124 #define LX_SIGEV_MAX            (sizeof (ltos_sigev) / sizeof (ltos_sigev[0]))
 125 #define LX_SIGEV_THREAD_ID      4
 126 
 127 long
 128 lx_clock_nanosleep(int clock, int flags, struct timespec *rqtp,
 129     struct timespec *rmtp)
 130 {
 131         int ret = 0;
 132         int err;
 133         struct timespec rqt, rmt;
 134 
 135         if (clock < 0 || clock >= LX_CLOCK_MAX)
 136                 return (-EINVAL);
 137 
 138         if (uucopy(rqtp, &rqt, sizeof (struct timespec)) < 0)
 139                 return (-EFAULT);
 140 
 141         /* the TIMER_RELTIME and TIMER_ABSTIME flags are the same on Linux */
 142         if ((err = clock_nanosleep(ltos_clock[clock], flags, &rqt, &rmt))
 143             != 0) {
 144                 if (err != EINTR)
 145                         return (-err);


 152 
 153         /*
 154          * Only copy values to rmtp if the timer is TIMER_RELTIME and rmtp is
 155          * non-NULL.
 156          */
 157         if (((flags & TIMER_RELTIME) == TIMER_RELTIME) && (rmtp != NULL) &&
 158             (uucopy(&rmt, rmtp, sizeof (struct timespec)) < 0))
 159                 return (-EFAULT);
 160 
 161         return (ret);
 162 }
 163 
 164 /*ARGSUSED*/
 165 long
 166 lx_adjtimex(void *tp)
 167 {
 168         return (-EPERM);
 169 }
 170 
 171 /*
 172  * Notification function for use with native SIGEV_THREAD in order to
 173  * emulate Linux SIGEV_THREAD_ID. Native SIGEV_THREAD is used as the
 174  * timer mechanism and B_SIGEV_THREAD_ID performs the actual event
 175  * delivery to the appropriate lx tid.
 176  */
 177 static void
 178 lx_sigev_thread_id(union sigval sival)
 179 {
 180         lx_sigevent_t *lev = (lx_sigevent_t *)sival.sival_ptr;
 181         syscall(SYS_brand, B_SIGEV_THREAD_ID, lev->lx_sigev_un.lx_tid,
 182             lev->lx_sigev_signo, lev->lx_sigev_value);
 183         free(lev);
 184 }
 185 
 186 
 187 /*
 188  * The Illumos timer_create man page says it accepts the following clocks:
 189  *   CLOCK_REALTIME (3) wall clock
 190  *   CLOCK_VIRTUAL (1)  user CPU usage clock - No Backend
 191  *   CLOCK_PROF (2)     user and system CPU usage clock - No Backend
 192  *   CLOCK_HIGHRES (4)  non-adjustable, high-resolution clock
 193  * However, in reality the Illumos timer_create only accepts CLOCK_REALTIME
 194  * and CLOCK_HIGHRES, and since we can't use CLOCK_HIGHRES in a zone, we're
 195  * down to one clock.
 196  */
 197 long
 198 lx_timer_create(int clock, struct sigevent *lx_sevp, timer_t *tid)
 199 {
 200         lx_sigevent_t lev;
 201         struct sigevent sev;
 202 
 203         if (clock < 0 || clock >= LX_TIMER_MAX)
 204                 return (-EINVAL);
 205 
 206         /* We have to convert the Linux sigevent layout to the Illumos layout */
 207         if (uucopy(lx_sevp, &lev, sizeof (lev)) < 0)
 208                 return (-EFAULT);
 209 
 210         if (lev.lx_sigev_notify < 0 || lev.lx_sigev_notify > LX_SIGEV_MAX)
 211                 return (-EINVAL);
 212 
 213         sev.sigev_notify = ltos_sigev[lev.lx_sigev_notify];
 214         sev.sigev_signo = ltos_signo[lev.lx_sigev_signo];
 215         sev.sigev_value = lev.lx_sigev_value;
 216 
 217         /*
 218          * Assume all Linux libc implementations map SIGEV_THREAD to
 219          * SIGEV_THREAD_ID and ignore passed-in attributes.
 220          */
 221         sev.sigev_notify_attributes = NULL;
 222 
 223         if (lev.lx_sigev_notify == LX_SIGEV_THREAD_ID) {
 224                 /*
 225                  * Pass the original lx sigevent_t to the native
 226                  * notify function so that it may pass it to the lx
 227                  * helper thread.
 228                  */
 229                 lx_sigevent_t *lev_copy = malloc(sizeof (lx_sigevent_t));
 230                 if (lev_copy == NULL)
 231                         return (-ENOMEM);
 232 
 233                 if (uucopy(&lev, lev_copy, sizeof (lx_sigevent_t)) < 0)
 234                         return (-EFAULT);
 235 
 236                 sev.sigev_notify_function = lx_sigev_thread_id;
 237                 sev.sigev_value.sival_ptr = lev_copy;
 238         }
 239 
 240         return ((timer_create(ltos_timer[clock], &sev, tid) < 0) ? -errno : 0);
 241 }
 242 
 243 long
 244 lx_timer_settime(timer_t tid, int flags, struct itimerspec *new_val,
 245     struct itimerspec *old_val)
 246 {
 247         return ((timer_settime(tid, flags, new_val, old_val) < 0) ? -errno : 0);
 248 }
 249 
 250 long
 251 lx_timer_gettime(timer_t tid, struct itimerspec *val)
 252 {
 253         return ((timer_gettime(tid, val) < 0) ? -errno : 0);
 254 }
 255 
 256 long
 257 lx_timer_getoverrun(timer_t tid)
 258 {
 259         int val;