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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-05-18 13:18:31 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-05-18 13:42:15 +0300
commit437fd90c0250dee670290f9b714253671a990160 (patch)
treeb871786c360704244a07411c69fb58da9ead4a06 /qemu/util/oslib-posix.c
parent5bbd6fe9b8bab2a93e548c5a53b032d1939eec05 (diff)
These changes are the raw update to qemu-2.6.
Collission happened in the following patches: migration: do cleanup operation after completion(738df5b9) Bug fix.(1750c932f86) kvmclock: add a new function to update env->tsc.(b52baab2) The code provided by the patches was already in the upstreamed version. Change-Id: I3cc11841a6a76ae20887b2e245710199e1ea7f9a Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'qemu/util/oslib-posix.c')
-rw-r--r--qemu/util/oslib-posix.c133
1 files changed, 81 insertions, 52 deletions
diff --git a/qemu/util/oslib-posix.c b/qemu/util/oslib-posix.c
index 3ae4987b6..6cc4b8f00 100644
--- a/qemu/util/oslib-posix.c
+++ b/qemu/util/oslib-posix.c
@@ -26,16 +26,8 @@
* THE SOFTWARE.
*/
-/* The following block of code temporarily renames the daemon() function so the
- compiler does not see the warning associated with it in stdlib.h on OSX */
-#ifdef __APPLE__
-#define daemon qemu_fake_daemon_function
-#include <stdlib.h>
-#undef daemon
-extern int daemon(int, int);
-#endif
-
-#if defined(__linux__) && (defined(__x86_64__) || defined(__arm__))
+#if defined(__linux__) && \
+ (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__))
/* Use 2 MiB alignment so transparent hugepages can be used by KVM.
Valgrind does not support alignments larger than 1 MiB,
therefore we need special code which handles running on Valgrind. */
@@ -46,32 +38,32 @@ extern int daemon(int, int);
#else
# define QEMU_VMALLOC_ALIGN getpagesize()
#endif
-#define HUGETLBFS_MAGIC 0x958458f6
+#include "qemu/osdep.h"
#include <termios.h>
-#include <unistd.h>
#include <termios.h>
#include <glib/gprintf.h>
-#include "config-host.h"
#include "sysemu/sysemu.h"
#include "trace.h"
+#include "qapi/error.h"
#include "qemu/sockets.h"
#include <sys/mman.h>
#include <libgen.h>
-#include <setjmp.h>
#include <sys/signal.h>
+#include "qemu/cutils.h"
#ifdef CONFIG_LINUX
#include <sys/syscall.h>
-#include <sys/vfs.h>
#endif
#ifdef __FreeBSD__
#include <sys/sysctl.h>
#endif
+#include <qemu/mmap-alloc.h>
+
int qemu_get_thread_id(void)
{
#if defined(__linux__)
@@ -128,10 +120,7 @@ void *qemu_memalign(size_t alignment, size_t size)
void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment)
{
size_t align = QEMU_VMALLOC_ALIGN;
- size_t total = size + align - getpagesize();
- void *ptr = mmap(0, total, PROT_READ | PROT_WRITE,
- MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
- size_t offset = QEMU_ALIGN_UP((uintptr_t)ptr, align) - (uintptr_t)ptr;
+ void *ptr = qemu_ram_mmap(-1, size, align, false);
if (ptr == MAP_FAILED) {
return NULL;
@@ -140,15 +129,6 @@ void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment)
if (alignment) {
*alignment = align;
}
- ptr += offset;
- total -= offset;
-
- if (offset > 0) {
- munmap(ptr - offset, offset);
- }
- if (total > size) {
- munmap(ptr + size, total - size);
- }
trace_qemu_anon_ram_alloc(size, ptr);
return ptr;
@@ -163,9 +143,7 @@ void qemu_vfree(void *ptr)
void qemu_anon_ram_free(void *ptr, size_t size)
{
trace_qemu_anon_ram_free(ptr, size);
- if (ptr) {
- munmap(ptr, size);
- }
+ qemu_ram_munmap(ptr, size);
}
void qemu_set_block(int fd)
@@ -352,26 +330,6 @@ static void sigbus_handler(int signal)
siglongjmp(sigjump, 1);
}
-static size_t fd_getpagesize(int fd)
-{
-#ifdef CONFIG_LINUX
- struct statfs fs;
- int ret;
-
- if (fd != -1) {
- do {
- ret = fstatfs(fd, &fs);
- } while (ret != 0 && errno == EINTR);
-
- if (ret == 0 && fs.f_type == HUGETLBFS_MAGIC) {
- return fs.f_bsize;
- }
- }
-#endif
-
- return getpagesize();
-}
-
void os_mem_prealloc(int fd, char *area, size_t memory)
{
int ret;
@@ -399,7 +357,7 @@ void os_mem_prealloc(int fd, char *area, size_t memory)
exit(1);
} else {
int i;
- size_t hpagesize = fd_getpagesize(fd);
+ size_t hpagesize = qemu_fd_getpagesize(fd);
size_t numpages = DIV_ROUND_UP(memory, hpagesize);
/* MAP_POPULATE silently ignores failures */
@@ -482,3 +440,74 @@ int qemu_read_password(char *buf, int buf_size)
printf("\n");
return ret;
}
+
+
+pid_t qemu_fork(Error **errp)
+{
+ sigset_t oldmask, newmask;
+ struct sigaction sig_action;
+ int saved_errno;
+ pid_t pid;
+
+ /*
+ * Need to block signals now, so that child process can safely
+ * kill off caller's signal handlers without a race.
+ */
+ sigfillset(&newmask);
+ if (pthread_sigmask(SIG_SETMASK, &newmask, &oldmask) != 0) {
+ error_setg_errno(errp, errno,
+ "cannot block signals");
+ return -1;
+ }
+
+ pid = fork();
+ saved_errno = errno;
+
+ if (pid < 0) {
+ /* attempt to restore signal mask, but ignore failure, to
+ * avoid obscuring the fork failure */
+ (void)pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
+ error_setg_errno(errp, saved_errno,
+ "cannot fork child process");
+ errno = saved_errno;
+ return -1;
+ } else if (pid) {
+ /* parent process */
+
+ /* Restore our original signal mask now that the child is
+ * safely running. Only documented failures are EFAULT (not
+ * possible, since we are using just-grabbed mask) or EINVAL
+ * (not possible, since we are using correct arguments). */
+ (void)pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
+ } else {
+ /* child process */
+ size_t i;
+
+ /* Clear out all signal handlers from parent so nothing
+ * unexpected can happen in our child once we unblock
+ * signals */
+ sig_action.sa_handler = SIG_DFL;
+ sig_action.sa_flags = 0;
+ sigemptyset(&sig_action.sa_mask);
+
+ for (i = 1; i < NSIG; i++) {
+ /* Only possible errors are EFAULT or EINVAL The former
+ * won't happen, the latter we expect, so no need to check
+ * return value */
+ (void)sigaction(i, &sig_action, NULL);
+ }
+
+ /* Unmask all signals in child, since we've no idea what the
+ * caller's done with their signal mask and don't want to
+ * propagate that to children */
+ sigemptyset(&newmask);
+ if (pthread_sigmask(SIG_SETMASK, &newmask, NULL) != 0) {
+ Error *local_err = NULL;
+ error_setg_errno(&local_err, errno,
+ "cannot unblock signals");
+ error_report_err(local_err);
+ _exit(1);
+ }
+ }
+ return pid;
+}