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-rw-r--r--kernel/futex.c84
1 files changed, 11 insertions, 73 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index b9b8aea5389e..9d260e838cff 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1120,9 +1120,10 @@ static int futex_wait(u32 __user *uaddr, u32 val, unsigned long time)
1120 * if there are waiters then it will block, it does PI, etc. (Due to 1120 * if there are waiters then it will block, it does PI, etc. (Due to
1121 * races the kernel might see a 0 value of the futex too.) 1121 * races the kernel might see a 0 value of the futex too.)
1122 */ 1122 */
1123static int do_futex_lock_pi(u32 __user *uaddr, int detect, int trylock, 1123static int futex_lock_pi(u32 __user *uaddr, int detect, unsigned long sec,
1124 struct hrtimer_sleeper *to) 1124 long nsec, int trylock)
1125{ 1125{
1126 struct hrtimer_sleeper timeout, *to = NULL;
1126 struct task_struct *curr = current; 1127 struct task_struct *curr = current;
1127 struct futex_hash_bucket *hb; 1128 struct futex_hash_bucket *hb;
1128 u32 uval, newval, curval; 1129 u32 uval, newval, curval;
@@ -1132,6 +1133,13 @@ static int do_futex_lock_pi(u32 __user *uaddr, int detect, int trylock,
1132 if (refill_pi_state_cache()) 1133 if (refill_pi_state_cache())
1133 return -ENOMEM; 1134 return -ENOMEM;
1134 1135
1136 if (sec != MAX_SCHEDULE_TIMEOUT) {
1137 to = &timeout;
1138 hrtimer_init(&to->timer, CLOCK_REALTIME, HRTIMER_ABS);
1139 hrtimer_init_sleeper(to, current);
1140 to->timer.expires = ktime_set(sec, nsec);
1141 }
1142
1135 q.pi_state = NULL; 1143 q.pi_state = NULL;
1136 retry: 1144 retry:
1137 down_read(&curr->mm->mmap_sem); 1145 down_read(&curr->mm->mmap_sem);
@@ -1307,7 +1315,7 @@ static int do_futex_lock_pi(u32 __user *uaddr, int detect, int trylock,
1307 if (!detect && ret == -EDEADLK && 0) 1315 if (!detect && ret == -EDEADLK && 0)
1308 force_sig(SIGKILL, current); 1316 force_sig(SIGKILL, current);
1309 1317
1310 return ret; 1318 return ret != -EINTR ? ret : -ERESTARTNOINTR;
1311 1319
1312 out_unlock_release_sem: 1320 out_unlock_release_sem:
1313 queue_unlock(&q, hb); 1321 queue_unlock(&q, hb);
@@ -1342,76 +1350,6 @@ static int do_futex_lock_pi(u32 __user *uaddr, int detect, int trylock,
1342} 1350}
1343 1351
1344/* 1352/*
1345 * Restart handler
1346 */
1347static long futex_lock_pi_restart(struct restart_block *restart)
1348{
1349 struct hrtimer_sleeper timeout, *to = NULL;
1350 int ret;
1351
1352 restart->fn = do_no_restart_syscall;
1353
1354 if (restart->arg2 || restart->arg3) {
1355 to = &timeout;
1356 hrtimer_init(&to->timer, CLOCK_REALTIME, HRTIMER_ABS);
1357 hrtimer_init_sleeper(to, current);
1358 to->timer.expires.tv64 = ((u64)restart->arg1 << 32) |
1359 (u64) restart->arg0;
1360 }
1361
1362 pr_debug("lock_pi restart: %p, %d (%d)\n",
1363 (u32 __user *)restart->arg0, current->pid);
1364
1365 ret = do_futex_lock_pi((u32 __user *)restart->arg0, restart->arg1,
1366 0, to);
1367
1368 if (ret != -EINTR)
1369 return ret;
1370
1371 restart->fn = futex_lock_pi_restart;
1372
1373 /* The other values are filled in */
1374 return -ERESTART_RESTARTBLOCK;
1375}
1376
1377/*
1378 * Called from the syscall entry below.
1379 */
1380static int futex_lock_pi(u32 __user *uaddr, int detect, unsigned long sec,
1381 long nsec, int trylock)
1382{
1383 struct hrtimer_sleeper timeout, *to = NULL;
1384 struct restart_block *restart;
1385 int ret;
1386
1387 if (sec != MAX_SCHEDULE_TIMEOUT) {
1388 to = &timeout;
1389 hrtimer_init(&to->timer, CLOCK_REALTIME, HRTIMER_ABS);
1390 hrtimer_init_sleeper(to, current);
1391 to->timer.expires = ktime_set(sec, nsec);
1392 }
1393
1394 ret = do_futex_lock_pi(uaddr, detect, trylock, to);
1395
1396 if (ret != -EINTR)
1397 return ret;
1398
1399 pr_debug("lock_pi interrupted: %p, %d (%d)\n", uaddr, current->pid);
1400
1401 restart = &current_thread_info()->restart_block;
1402 restart->fn = futex_lock_pi_restart;
1403 restart->arg0 = (unsigned long) uaddr;
1404 restart->arg1 = detect;
1405 if (to) {
1406 restart->arg2 = to->timer.expires.tv64 & 0xFFFFFFFF;
1407 restart->arg3 = to->timer.expires.tv64 >> 32;
1408 } else
1409 restart->arg2 = restart->arg3 = 0;
1410
1411 return -ERESTART_RESTARTBLOCK;
1412}
1413
1414/*
1415 * Userspace attempted a TID -> 0 atomic transition, and failed. 1353 * Userspace attempted a TID -> 0 atomic transition, and failed.
1416 * This is the in-kernel slowpath: we look up the PI state (if any), 1354 * This is the in-kernel slowpath: we look up the PI state (if any),
1417 * and do the rt-mutex unlock. 1355 * and do the rt-mutex unlock.