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-rw-r--r--src/shared/sigbus.c152
1 files changed, 0 insertions, 152 deletions
diff --git a/src/shared/sigbus.c b/src/shared/sigbus.c
deleted file mode 100644
index 0108603fe8..0000000000
--- a/src/shared/sigbus.c
+++ /dev/null
@@ -1,152 +0,0 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2014 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <signal.h>
-#include <sys/mman.h>
-
-#include "macro.h"
-#include "util.h"
-#include "sigbus.h"
-
-#define SIGBUS_QUEUE_MAX 64
-
-static struct sigaction old_sigaction;
-static unsigned n_installed = 0;
-
-/* We maintain a fixed size list of page addresses that triggered a
- SIGBUS. We access with list with atomic operations, so that we
- don't have to deal with locks between signal handler and main
- programs in possibly multiple threads. */
-
-static void* volatile sigbus_queue[SIGBUS_QUEUE_MAX];
-static volatile sig_atomic_t n_sigbus_queue = 0;
-
-static void sigbus_push(void *addr) {
- unsigned u;
-
- assert(addr);
-
- /* Find a free place, increase the number of entries and leave, if we can */
- for (u = 0; u < SIGBUS_QUEUE_MAX; u++)
- if (__sync_bool_compare_and_swap(&sigbus_queue[u], NULL, addr)) {
- __sync_fetch_and_add(&n_sigbus_queue, 1);
- return;
- }
-
- /* If we can't, make sure the queue size is out of bounds, to
- * mark it as overflow */
- for (;;) {
- unsigned c;
-
- __sync_synchronize();
- c = n_sigbus_queue;
-
- if (c > SIGBUS_QUEUE_MAX) /* already overflow */
- return;
-
- if (__sync_bool_compare_and_swap(&n_sigbus_queue, c, c + SIGBUS_QUEUE_MAX))
- return;
- }
-}
-
-int sigbus_pop(void **ret) {
- assert(ret);
-
- for (;;) {
- unsigned u, c;
-
- __sync_synchronize();
- c = n_sigbus_queue;
-
- if (_likely_(c == 0))
- return 0;
-
- if (_unlikely_(c >= SIGBUS_QUEUE_MAX))
- return -EOVERFLOW;
-
- for (u = 0; u < SIGBUS_QUEUE_MAX; u++) {
- void *addr;
-
- addr = sigbus_queue[u];
- if (!addr)
- continue;
-
- if (__sync_bool_compare_and_swap(&sigbus_queue[u], addr, NULL)) {
- __sync_fetch_and_sub(&n_sigbus_queue, 1);
- *ret = addr;
- return 1;
- }
- }
- }
-}
-
-static void sigbus_handler(int sn, siginfo_t *si, void *data) {
- unsigned long ul;
- void *aligned;
-
- assert(sn == SIGBUS);
- assert(si);
-
- if (si->si_code != BUS_ADRERR || !si->si_addr) {
- assert_se(sigaction(SIGBUS, &old_sigaction, NULL) == 0);
- raise(SIGBUS);
- return;
- }
-
- ul = (unsigned long) si->si_addr;
- ul = ul / page_size();
- ul = ul * page_size();
- aligned = (void*) ul;
-
- /* Let's remember which address failed */
- sigbus_push(aligned);
-
- /* Replace mapping with an anonymous page, so that the
- * execution can continue, however with a zeroed out page */
- assert_se(mmap(aligned, page_size(), PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED, -1, 0) == aligned);
-}
-
-void sigbus_install(void) {
- struct sigaction sa = {
- .sa_sigaction = sigbus_handler,
- .sa_flags = SA_SIGINFO,
- };
-
- n_installed++;
-
- if (n_installed == 1)
- assert_se(sigaction(SIGBUS, &sa, &old_sigaction) == 0);
-
- return;
-}
-
-void sigbus_reset(void) {
-
- if (n_installed <= 0)
- return;
-
- n_installed--;
-
- if (n_installed == 0)
- assert_se(sigaction(SIGBUS, &old_sigaction, NULL) == 0);
-
- return;
-}