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-rw-r--r--arch/um/os-Linux/aio.c5
-rw-r--r--arch/um/os-Linux/file.c15
-rw-r--r--arch/um/os-Linux/main.c3
-rw-r--r--arch/um/os-Linux/mem.c236
-rw-r--r--arch/um/os-Linux/process.c53
-rw-r--r--arch/um/os-Linux/sigio.c2
-rw-r--r--arch/um/os-Linux/signal.c18
-rw-r--r--arch/um/os-Linux/skas/process.c10
-rw-r--r--arch/um/os-Linux/start_up.c2
-rw-r--r--arch/um/os-Linux/time.c2
-rw-r--r--arch/um/os-Linux/util.c10
11 files changed, 185 insertions, 171 deletions
diff --git a/arch/um/os-Linux/aio.c b/arch/um/os-Linux/aio.c
index 3a6bc2af096..014eb35fd13 100644
--- a/arch/um/os-Linux/aio.c
+++ b/arch/um/os-Linux/aio.c
@@ -104,8 +104,7 @@ static int aio_thread(void *arg)
struct io_event event;
int err, n, reply_fd;
- signal(SIGWINCH, SIG_IGN);
-
+ os_fix_helper_signals();
while (1) {
n = io_getevents(ctx, 1, 1, &event, NULL);
if (n < 0) {
@@ -173,7 +172,7 @@ static int not_aio_thread(void *arg)
struct aio_thread_reply reply;
int err;
- signal(SIGWINCH, SIG_IGN);
+ os_fix_helper_signals();
while (1) {
err = read(aio_req_fd_r, &req, sizeof(req));
if (err != sizeof(req)) {
diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
index c17bd6f7d67..08d90fba952 100644
--- a/arch/um/os-Linux/file.c
+++ b/arch/um/os-Linux/file.c
@@ -237,6 +237,12 @@ void os_close_file(int fd)
{
close(fd);
}
+int os_fsync_file(int fd)
+{
+ if (fsync(fd) < 0)
+ return -errno;
+ return 0;
+}
int os_seek_file(int fd, unsigned long long offset)
{
@@ -266,6 +272,15 @@ int os_write_file(int fd, const void *buf, int len)
return n;
}
+int os_sync_file(int fd)
+{
+ int n = fsync(fd);
+
+ if (n < 0)
+ return -errno;
+ return n;
+}
+
int os_file_size(const char *file, unsigned long long *size_out)
{
struct uml_stat buf;
diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c
index 749c96da7b9..df9191acd92 100644
--- a/arch/um/os-Linux/main.c
+++ b/arch/um/os-Linux/main.c
@@ -123,6 +123,8 @@ int __init main(int argc, char **argv, char **envp)
setup_env_path();
+ setsid();
+
new_argv = malloc((argc + 1) * sizeof(char *));
if (new_argv == NULL) {
perror("Mallocing argv");
@@ -149,6 +151,7 @@ int __init main(int argc, char **argv, char **envp)
#endif
do_uml_initcalls();
+ change_sig(SIGPIPE, 0);
ret = linux_main(argc, argv);
/*
diff --git a/arch/um/os-Linux/mem.c b/arch/um/os-Linux/mem.c
index ba4398056fe..897e9ad0c10 100644
--- a/arch/um/os-Linux/mem.c
+++ b/arch/um/os-Linux/mem.c
@@ -12,189 +12,117 @@
#include <string.h>
#include <sys/stat.h>
#include <sys/mman.h>
-#include <sys/param.h>
+#include <sys/vfs.h>
+#include <linux/magic.h>
#include <init.h>
#include <os.h>
-/* Modified by which_tmpdir, which is called during early boot */
-static char *default_tmpdir = "/tmp";
-
-/*
- * Modified when creating the physical memory file and when checking
- * the tmp filesystem for usability, both happening during early boot.
- */
+/* Set by make_tempfile() during early boot. */
static char *tempdir = NULL;
-static void __init find_tempdir(void)
+/* Check if dir is on tmpfs. Return 0 if yes, -1 if no or error. */
+static int __init check_tmpfs(const char *dir)
{
- const char *dirs[] = { "TMP", "TEMP", "TMPDIR", NULL };
- int i;
- char *dir = NULL;
-
- if (tempdir != NULL)
- /* We've already been called */
- return;
- for (i = 0; dirs[i]; i++) {
- dir = getenv(dirs[i]);
- if ((dir != NULL) && (*dir != '\0'))
- break;
- }
- if ((dir == NULL) || (*dir == '\0'))
- dir = default_tmpdir;
-
- tempdir = malloc(strlen(dir) + 2);
- if (tempdir == NULL) {
- fprintf(stderr, "Failed to malloc tempdir, "
- "errno = %d\n", errno);
- return;
+ struct statfs st;
+
+ printf("Checking if %s is on tmpfs...", dir);
+ if (statfs(dir, &st) < 0) {
+ printf("%s\n", strerror(errno));
+ } else if (st.f_type != TMPFS_MAGIC) {
+ printf("no\n");
+ } else {
+ printf("OK\n");
+ return 0;
}
- strcpy(tempdir, dir);
- strcat(tempdir, "/");
+ return -1;
}
/*
- * This will return 1, with the first character in buf being the
- * character following the next instance of c in the file. This will
- * read the file as needed. If there's an error, -errno is returned;
- * if the end of the file is reached, 0 is returned.
+ * Choose the tempdir to use. We want something on tmpfs so that our memory is
+ * not subject to the host's vm.dirty_ratio. If a tempdir is specified in the
+ * environment, we use that even if it's not on tmpfs, but we warn the user.
+ * Otherwise, we try common tmpfs locations, and if no tmpfs directory is found
+ * then we fall back to /tmp.
*/
-static int next(int fd, char *buf, size_t size, char c)
+static char * __init choose_tempdir(void)
{
- ssize_t n;
- size_t len;
- char *ptr;
-
- while ((ptr = strchr(buf, c)) == NULL) {
- n = read(fd, buf, size - 1);
- if (n == 0)
- return 0;
- else if (n < 0)
- return -errno;
-
- buf[n] = '\0';
+ static const char * const vars[] = {
+ "TMPDIR",
+ "TMP",
+ "TEMP",
+ NULL
+ };
+ static const char fallback_dir[] = "/tmp";
+ static const char * const tmpfs_dirs[] = {
+ "/dev/shm",
+ fallback_dir,
+ NULL
+ };
+ int i;
+ const char *dir;
+
+ printf("Checking environment variables for a tempdir...");
+ for (i = 0; vars[i]; i++) {
+ dir = getenv(vars[i]);
+ if ((dir != NULL) && (*dir != '\0')) {
+ printf("%s\n", dir);
+ if (check_tmpfs(dir) >= 0)
+ goto done;
+ else
+ goto warn;
+ }
}
+ printf("none found\n");
- ptr++;
- len = strlen(ptr);
- memmove(buf, ptr, len + 1);
-
- /*
- * Refill the buffer so that if there's a partial string that we care
- * about, it will be completed, and we can recognize it.
- */
- n = read(fd, &buf[len], size - len - 1);
- if (n < 0)
- return -errno;
+ for (i = 0; tmpfs_dirs[i]; i++) {
+ dir = tmpfs_dirs[i];
+ if (check_tmpfs(dir) >= 0)
+ goto done;
+ }
- buf[len + n] = '\0';
- return 1;
+ dir = fallback_dir;
+warn:
+ printf("Warning: tempdir %s is not on tmpfs\n", dir);
+done:
+ /* Make a copy since getenv results may not remain valid forever. */
+ return strdup(dir);
}
-/* which_tmpdir is called only during early boot */
-static int checked_tmpdir = 0;
-
/*
- * Look for a tmpfs mounted at /dev/shm. I couldn't find a cleaner
- * way to do this than to parse /proc/mounts. statfs will return the
- * same filesystem magic number and fs id for both /dev and /dev/shm
- * when they are both tmpfs, so you can't tell if they are different
- * filesystems. Also, there seems to be no other way of finding the
- * mount point of a filesystem from within it.
- *
- * If a /dev/shm tmpfs entry is found, then we switch to using it.
- * Otherwise, we stay with the default /tmp.
+ * Create an unlinked tempfile in a suitable tempdir. template must be the
+ * basename part of the template with a leading '/'.
*/
-static void which_tmpdir(void)
-{
- int fd, found;
- char buf[128] = { '\0' };
-
- if (checked_tmpdir)
- return;
-
- checked_tmpdir = 1;
-
- printf("Checking for tmpfs mount on /dev/shm...");
-
- fd = open("/proc/mounts", O_RDONLY);
- if (fd < 0) {
- printf("failed to open /proc/mounts, errno = %d\n", errno);
- return;
- }
-
- while (1) {
- found = next(fd, buf, ARRAY_SIZE(buf), ' ');
- if (found != 1)
- break;
-
- if (!strncmp(buf, "/dev/shm", strlen("/dev/shm")))
- goto found;
-
- found = next(fd, buf, ARRAY_SIZE(buf), '\n');
- if (found != 1)
- break;
- }
-
-err:
- if (found == 0)
- printf("nothing mounted on /dev/shm\n");
- else if (found < 0)
- printf("read returned errno %d\n", -found);
-
-out:
- close(fd);
-
- return;
-
-found:
- found = next(fd, buf, ARRAY_SIZE(buf), ' ');
- if (found != 1)
- goto err;
-
- if (strncmp(buf, "tmpfs", strlen("tmpfs"))) {
- printf("not tmpfs\n");
- goto out;
- }
-
- printf("OK\n");
- default_tmpdir = "/dev/shm";
- goto out;
-}
-
-static int __init make_tempfile(const char *template, char **out_tempname,
- int do_unlink)
+static int __init make_tempfile(const char *template)
{
char *tempname;
int fd;
- which_tmpdir();
- tempname = malloc(MAXPATHLEN);
+ if (tempdir == NULL) {
+ tempdir = choose_tempdir();
+ if (tempdir == NULL) {
+ fprintf(stderr, "Failed to choose tempdir: %s\n",
+ strerror(errno));
+ return -1;
+ }
+ }
+
+ tempname = malloc(strlen(tempdir) + strlen(template) + 1);
if (tempname == NULL)
return -1;
- find_tempdir();
- if ((tempdir == NULL) || (strlen(tempdir) >= MAXPATHLEN))
- goto out;
-
- if (template[0] != '/')
- strcpy(tempname, tempdir);
- else
- tempname[0] = '\0';
- strncat(tempname, template, MAXPATHLEN-1-strlen(tempname));
+ strcpy(tempname, tempdir);
+ strcat(tempname, template);
fd = mkstemp(tempname);
if (fd < 0) {
fprintf(stderr, "open - cannot create %s: %s\n", tempname,
strerror(errno));
goto out;
}
- if (do_unlink && (unlink(tempname) < 0)) {
+ if (unlink(tempname) < 0) {
perror("unlink");
goto close;
}
- if (out_tempname) {
- *out_tempname = tempname;
- } else
- free(tempname);
+ free(tempname);
return fd;
close:
close(fd);
@@ -203,14 +131,14 @@ out:
return -1;
}
-#define TEMPNAME_TEMPLATE "vm_file-XXXXXX"
+#define TEMPNAME_TEMPLATE "/vm_file-XXXXXX"
static int __init create_tmp_file(unsigned long long len)
{
int fd, err;
char zero;
- fd = make_tempfile(TEMPNAME_TEMPLATE, NULL, 1);
+ fd = make_tempfile(TEMPNAME_TEMPLATE);
if (fd < 0)
exit(1);
@@ -254,7 +182,6 @@ int __init create_mem_file(unsigned long long len)
return fd;
}
-
void __init check_tmpexec(void)
{
void *addr;
@@ -262,14 +189,13 @@ void __init check_tmpexec(void)
addr = mmap(NULL, UM_KERN_PAGE_SIZE,
PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE, fd, 0);
- printf("Checking PROT_EXEC mmap in %s...",tempdir);
- fflush(stdout);
+ printf("Checking PROT_EXEC mmap in %s...", tempdir);
if (addr == MAP_FAILED) {
err = errno;
- perror("failed");
+ printf("%s\n", strerror(err));
close(fd);
if (err == EPERM)
- printf("%s must be not mounted noexec\n",tempdir);
+ printf("%s must be not mounted noexec\n", tempdir);
exit(1);
}
printf("OK\n");
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
index b8f34c9e53a..33496fe2bb5 100644
--- a/arch/um/os-Linux/process.c
+++ b/arch/um/os-Linux/process.c
@@ -4,6 +4,7 @@
*/
#include <stdio.h>
+#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
@@ -232,6 +233,57 @@ out:
return ok;
}
+static int os_page_mincore(void *addr)
+{
+ char vec[2];
+ int ret;
+
+ ret = mincore(addr, UM_KERN_PAGE_SIZE, vec);
+ if (ret < 0) {
+ if (errno == ENOMEM || errno == EINVAL)
+ return 0;
+ else
+ return -errno;
+ }
+
+ return vec[0] & 1;
+}
+
+int os_mincore(void *addr, unsigned long len)
+{
+ char *vec;
+ int ret, i;
+
+ if (len <= UM_KERN_PAGE_SIZE)
+ return os_page_mincore(addr);
+
+ vec = calloc(1, (len + UM_KERN_PAGE_SIZE - 1) / UM_KERN_PAGE_SIZE);
+ if (!vec)
+ return -ENOMEM;
+
+ ret = mincore(addr, UM_KERN_PAGE_SIZE, vec);
+ if (ret < 0) {
+ if (errno == ENOMEM || errno == EINVAL)
+ ret = 0;
+ else
+ ret = -errno;
+
+ goto out;
+ }
+
+ for (i = 0; i < ((len + UM_KERN_PAGE_SIZE - 1) / UM_KERN_PAGE_SIZE); i++) {
+ if (!(vec[i] & 1)) {
+ ret = 0;
+ goto out;
+ }
+ }
+
+ ret = 1;
+out:
+ free(vec);
+ return ret;
+}
+
void init_new_thread_signals(void)
{
set_handler(SIGSEGV);
@@ -242,5 +294,4 @@ void init_new_thread_signals(void)
signal(SIGHUP, SIG_IGN);
set_handler(SIGIO);
signal(SIGWINCH, SIG_IGN);
- signal(SIGTERM, SIG_DFL);
}
diff --git a/arch/um/os-Linux/sigio.c b/arch/um/os-Linux/sigio.c
index 8b61cc0e82c..46e762f926e 100644
--- a/arch/um/os-Linux/sigio.c
+++ b/arch/um/os-Linux/sigio.c
@@ -55,7 +55,7 @@ static int write_sigio_thread(void *unused)
int i, n, respond_fd;
char c;
- signal(SIGWINCH, SIG_IGN);
+ os_fix_helper_signals();
fds = &current_poll;
while (1) {
n = poll(fds->poll, fds->used, -1);
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index b1469fe9329..7b605e4dfff 100644
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -15,7 +15,7 @@
#include <sysdep/mcontext.h>
#include "internal.h"
-void (*sig_info[NSIG])(int, siginfo_t *, struct uml_pt_regs *) = {
+void (*sig_info[NSIG])(int, struct siginfo *, struct uml_pt_regs *) = {
[SIGTRAP] = relay_signal,
[SIGFPE] = relay_signal,
[SIGILL] = relay_signal,
@@ -25,7 +25,7 @@ void (*sig_info[NSIG])(int, siginfo_t *, struct uml_pt_regs *) = {
[SIGIO] = sigio_handler,
[SIGVTALRM] = timer_handler };
-static void sig_handler_common(int sig, siginfo_t *si, mcontext_t *mc)
+static void sig_handler_common(int sig, struct siginfo *si, mcontext_t *mc)
{
struct uml_pt_regs r;
int save_errno = errno;
@@ -61,7 +61,7 @@ static void sig_handler_common(int sig, siginfo_t *si, mcontext_t *mc)
static int signals_enabled;
static unsigned int signals_pending;
-void sig_handler(int sig, siginfo_t *si, mcontext_t *mc)
+void sig_handler(int sig, struct siginfo *si, mcontext_t *mc)
{
int enabled;
@@ -120,7 +120,7 @@ void set_sigstack(void *sig_stack, int size)
panic("enabling signal stack failed, errno = %d\n", errno);
}
-static void (*handlers[_NSIG])(int sig, siginfo_t *si, mcontext_t *mc) = {
+static void (*handlers[_NSIG])(int sig, struct siginfo *si, mcontext_t *mc) = {
[SIGSEGV] = sig_handler,
[SIGBUS] = sig_handler,
[SIGILL] = sig_handler,
@@ -162,7 +162,7 @@ static void hard_handler(int sig, siginfo_t *si, void *p)
while ((sig = ffs(pending)) != 0){
sig--;
pending &= ~(1 << sig);
- (*handlers[sig])(sig, si, mc);
+ (*handlers[sig])(sig, (struct siginfo *)si, mc);
}
/*
@@ -304,3 +304,11 @@ int set_signals(int enable)
return ret;
}
+
+int os_is_signal_stack(void)
+{
+ stack_t ss;
+ sigaltstack(NULL, &ss);
+
+ return ss.ss_flags & SS_ONSTACK;
+}
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 4625949bf1e..908579f2b0a 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -409,7 +409,7 @@ void userspace(struct uml_pt_regs *regs)
if (WIFSTOPPED(status)) {
int sig = WSTOPSIG(status);
- ptrace(PTRACE_GETSIGINFO, pid, 0, &si);
+ ptrace(PTRACE_GETSIGINFO, pid, 0, (struct siginfo *)&si);
switch (sig) {
case SIGSEGV:
@@ -417,7 +417,7 @@ void userspace(struct uml_pt_regs *regs)
!ptrace_faultinfo) {
get_skas_faultinfo(pid,
&regs->faultinfo);
- (*sig_info[SIGSEGV])(SIGSEGV, &si,
+ (*sig_info[SIGSEGV])(SIGSEGV, (struct siginfo *)&si,
regs);
}
else handle_segv(pid, regs);
@@ -426,14 +426,14 @@ void userspace(struct uml_pt_regs *regs)
handle_trap(pid, regs, local_using_sysemu);
break;
case SIGTRAP:
- relay_signal(SIGTRAP, &si, regs);
+ relay_signal(SIGTRAP, (struct siginfo *)&si, regs);
break;
case SIGVTALRM:
now = os_nsecs();
if (now < nsecs)
break;
block_signals();
- (*sig_info[sig])(sig, &si, regs);
+ (*sig_info[sig])(sig, (struct siginfo *)&si, regs);
unblock_signals();
nsecs = timer.it_value.tv_sec *
UM_NSEC_PER_SEC +
@@ -447,7 +447,7 @@ void userspace(struct uml_pt_regs *regs)
case SIGFPE:
case SIGWINCH:
block_signals();
- (*sig_info[sig])(sig, &si, regs);
+ (*sig_info[sig])(sig, (struct siginfo *)&si, regs);
unblock_signals();
break;
default:
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index da4b9e9999f..337518c5042 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -15,6 +15,8 @@
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/wait.h>
+#include <sys/time.h>
+#include <sys/resource.h>
#include <asm/unistd.h>
#include <init.h>
#include <os.h>
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c
index fac388cb464..e9824d5dd7d 100644
--- a/arch/um/os-Linux/time.c
+++ b/arch/um/os-Linux/time.c
@@ -79,7 +79,7 @@ long long os_nsecs(void)
return timeval_to_ns(&tv);
}
-#ifdef UML_CONFIG_NO_HZ
+#ifdef UML_CONFIG_NO_HZ_COMMON
static int after_sleep_interval(struct timespec *ts)
{
return 0;
diff --git a/arch/um/os-Linux/util.c b/arch/um/os-Linux/util.c
index 492ef5e6e16..faee55ef6d2 100644
--- a/arch/um/os-Linux/util.c
+++ b/arch/um/os-Linux/util.c
@@ -94,6 +94,16 @@ static inline void __attribute__ ((noreturn)) uml_abort(void)
exit(127);
}
+/*
+ * UML helper threads must not handle SIGWINCH/INT/TERM
+ */
+void os_fix_helper_signals(void)
+{
+ signal(SIGWINCH, SIG_IGN);
+ signal(SIGINT, SIG_DFL);
+ signal(SIGTERM, SIG_DFL);
+}
+
void os_dump_core(void)
{
int pid;
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 22:55:19 +0000