2006-03-24 18:18:41

by Jeff Dike

[permalink] [raw]
Subject: [PATCH 7/16] UML - Move sigio_user.c to os-Linux/sigio.c

The serial UML OS-abstraction layer patch (um/kernel dir).

This moves sigio_user.c to os-Linux dir

Signed-off-by: Gennady Sharapov <[email protected]>
Signed-off-by: Jeff Dike <[email protected]>

Index: linux-2.6.16/arch/um/include/os.h
===================================================================
--- linux-2.6.16.orig/arch/um/include/os.h 2006-03-23 17:23:54.000000000 -0500
+++ linux-2.6.16/arch/um/include/os.h 2006-03-23 17:26:25.000000000 -0500
@@ -311,4 +311,9 @@ extern void os_set_pollfd(int i, int fd)
extern void os_set_ioignore(void);
extern void init_irq_signals(int on_sigstack);

+/* sigio.c */
+extern void write_sigio_workaround(void);
+extern int add_sigio_fd(int fd, int read);
+extern int ignore_sigio_fd(int fd);
+
#endif
Index: linux-2.6.16/arch/um/include/sigio.h
===================================================================
--- linux-2.6.16.orig/arch/um/include/sigio.h 2006-03-23 17:23:54.000000000 -0500
+++ linux-2.6.16/arch/um/include/sigio.h 2006-03-23 17:26:25.000000000 -0500
@@ -8,8 +8,6 @@

extern int write_sigio_irq(int fd);
extern int register_sigio_fd(int fd);
-extern int add_sigio_fd(int fd, int read);
-extern int ignore_sigio_fd(int fd);
extern void sigio_lock(void);
extern void sigio_unlock(void);

Index: linux-2.6.16/arch/um/include/user_util.h
===================================================================
--- linux-2.6.16.orig/arch/um/include/user_util.h 2006-03-23 17:15:05.000000000 -0500
+++ linux-2.6.16/arch/um/include/user_util.h 2006-03-23 17:26:25.000000000 -0500
@@ -58,7 +58,6 @@ extern int attach(int pid);
extern void kill_child_dead(int pid);
extern int cont(int pid);
extern void check_sigio(void);
-extern void write_sigio_workaround(void);
extern void arch_check_bugs(void);
extern int cpu_feature(char *what, char *buf, int len);
extern int arch_handle_signal(int sig, union uml_pt_regs *regs);
Index: linux-2.6.16/arch/um/kernel/Makefile
===================================================================
--- linux-2.6.16.orig/arch/um/kernel/Makefile 2006-03-23 17:15:05.000000000 -0500
+++ linux-2.6.16/arch/um/kernel/Makefile 2006-03-23 17:26:25.000000000 -0500
@@ -8,7 +8,7 @@ clean-files :=

obj-y = config.o exec_kern.o exitcode.o \
init_task.o irq.o ksyms.o mem.o physmem.o \
- process_kern.o ptrace.o reboot.o resource.o sigio_user.o sigio_kern.o \
+ process_kern.o ptrace.o reboot.o resource.o sigio_kern.o \
signal_kern.o smp.o syscall_kern.o sysrq.o \
time_kern.o tlb.o trap_kern.o uaccess.o um_arch.o umid.o

Index: linux-2.6.16/arch/um/os-Linux/Makefile
===================================================================
--- linux-2.6.16.orig/arch/um/os-Linux/Makefile 2006-03-23 17:15:05.000000000 -0500
+++ linux-2.6.16/arch/um/os-Linux/Makefile 2006-03-23 17:26:25.000000000 -0500
@@ -3,14 +3,15 @@
# Licensed under the GPL
#

-obj-y = aio.o elf_aux.o file.o helper.o irq.o main.o mem.o process.o signal.o \
- start_up.o time.o trap.o tt.o tty.o uaccess.o umid.o user_syms.o \
- util.o drivers/ sys-$(SUBARCH)/
+obj-y = aio.o elf_aux.o file.o helper.o irq.o main.o mem.o process.o sigio.o \
+ signal.o start_up.o time.o trap.o tt.o tty.o uaccess.o umid.o \
+ user_syms.o util.o drivers/ sys-$(SUBARCH)/

obj-$(CONFIG_MODE_SKAS) += skas/

USER_OBJS := aio.o elf_aux.o file.o helper.o irq.o main.o mem.o process.o \
- signal.o start_up.o time.o trap.o tt.o tty.o uaccess.o umid.o util.o
+ sigio.o signal.o start_up.o time.o trap.o tt.o tty.o uaccess.o umid.o \
+ util.o

elf_aux.o: $(ARCH_DIR)/kernel-offsets.h
CFLAGS_elf_aux.o += -I$(objtree)/arch/um
Index: linux-2.6.16/arch/um/os-Linux/sigio.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.16/arch/um/os-Linux/sigio.c 2006-03-23 17:30:27.000000000 -0500
@@ -0,0 +1,324 @@
+/*
+ * Copyright (C) 2002 Jeff Dike ([email protected])
+ * Licensed under the GPL
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <termios.h>
+#include <pty.h>
+#include <signal.h>
+#include <errno.h>
+#include <string.h>
+#include <sched.h>
+#include <sys/socket.h>
+#include <sys/poll.h>
+#include "init.h"
+#include "user.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "sigio.h"
+#include "os.h"
+
+/* Protected by sigio_lock(), also used by sigio_cleanup, which is an
+ * exitcall.
+ */
+static int write_sigio_pid = -1;
+
+/* These arrays are initialized before the sigio thread is started, and
+ * the descriptors closed after it is killed. So, it can't see them change.
+ * On the UML side, they are changed under the sigio_lock.
+ */
+static int write_sigio_fds[2] = { -1, -1 };
+static int sigio_private[2] = { -1, -1 };
+
+struct pollfds {
+ struct pollfd *poll;
+ int size;
+ int used;
+};
+
+/* Protected by sigio_lock(). Used by the sigio thread, but the UML thread
+ * synchronizes with it.
+ */
+struct pollfds current_poll = {
+ .poll = NULL,
+ .size = 0,
+ .used = 0
+};
+
+struct pollfds next_poll = {
+ .poll = NULL,
+ .size = 0,
+ .used = 0
+};
+
+static int write_sigio_thread(void *unused)
+{
+ struct pollfds *fds, tmp;
+ struct pollfd *p;
+ int i, n, respond_fd;
+ char c;
+
+ signal(SIGWINCH, SIG_IGN);
+ fds = &current_poll;
+ while(1){
+ n = poll(fds->poll, fds->used, -1);
+ if(n < 0){
+ if(errno == EINTR) continue;
+ printk("write_sigio_thread : poll returned %d, "
+ "errno = %d\n", n, errno);
+ }
+ for(i = 0; i < fds->used; i++){
+ p = &fds->poll[i];
+ if(p->revents == 0) continue;
+ if(p->fd == sigio_private[1]){
+ n = os_read_file(sigio_private[1], &c, sizeof(c));
+ if(n != sizeof(c))
+ printk("write_sigio_thread : "
+ "read failed, err = %d\n", -n);
+ tmp = current_poll;
+ current_poll = next_poll;
+ next_poll = tmp;
+ respond_fd = sigio_private[1];
+ }
+ else {
+ respond_fd = write_sigio_fds[1];
+ fds->used--;
+ memmove(&fds->poll[i], &fds->poll[i + 1],
+ (fds->used - i) * sizeof(*fds->poll));
+ }
+
+ n = os_write_file(respond_fd, &c, sizeof(c));
+ if(n != sizeof(c))
+ printk("write_sigio_thread : write failed, "
+ "err = %d\n", -n);
+ }
+ }
+
+ return 0;
+}
+
+static int need_poll(int n)
+{
+ if(n <= next_poll.size){
+ next_poll.used = n;
+ return(0);
+ }
+ kfree(next_poll.poll);
+ next_poll.poll = um_kmalloc_atomic(n * sizeof(struct pollfd));
+ if(next_poll.poll == NULL){
+ printk("need_poll : failed to allocate new pollfds\n");
+ next_poll.size = 0;
+ next_poll.used = 0;
+ return(-1);
+ }
+ next_poll.size = n;
+ next_poll.used = n;
+ return(0);
+}
+
+/* Must be called with sigio_lock held, because it's needed by the marked
+ * critical section. */
+static void update_thread(void)
+{
+ unsigned long flags;
+ int n;
+ char c;
+
+ flags = set_signals(0);
+ n = os_write_file(sigio_private[0], &c, sizeof(c));
+ if(n != sizeof(c)){
+ printk("update_thread : write failed, err = %d\n", -n);
+ goto fail;
+ }
+
+ n = os_read_file(sigio_private[0], &c, sizeof(c));
+ if(n != sizeof(c)){
+ printk("update_thread : read failed, err = %d\n", -n);
+ goto fail;
+ }
+
+ set_signals(flags);
+ return;
+ fail:
+ /* Critical section start */
+ if(write_sigio_pid != -1)
+ os_kill_process(write_sigio_pid, 1);
+ write_sigio_pid = -1;
+ close(sigio_private[0]);
+ close(sigio_private[1]);
+ close(write_sigio_fds[0]);
+ close(write_sigio_fds[1]);
+ /* Critical section end */
+ set_signals(flags);
+}
+
+int add_sigio_fd(int fd, int read)
+{
+ int err = 0, i, n, events;
+
+ sigio_lock();
+ for(i = 0; i < current_poll.used; i++){
+ if(current_poll.poll[i].fd == fd)
+ goto out;
+ }
+
+ n = current_poll.used + 1;
+ err = need_poll(n);
+ if(err)
+ goto out;
+
+ for(i = 0; i < current_poll.used; i++)
+ next_poll.poll[i] = current_poll.poll[i];
+
+ if(read) events = POLLIN;
+ else events = POLLOUT;
+
+ next_poll.poll[n - 1] = ((struct pollfd) { .fd = fd,
+ .events = events,
+ .revents = 0 });
+ update_thread();
+ out:
+ sigio_unlock();
+ return(err);
+}
+
+int ignore_sigio_fd(int fd)
+{
+ struct pollfd *p;
+ int err = 0, i, n = 0;
+
+ sigio_lock();
+ for(i = 0; i < current_poll.used; i++){
+ if(current_poll.poll[i].fd == fd) break;
+ }
+ if(i == current_poll.used)
+ goto out;
+
+ err = need_poll(current_poll.used - 1);
+ if(err)
+ goto out;
+
+ for(i = 0; i < current_poll.used; i++){
+ p = &current_poll.poll[i];
+ if(p->fd != fd) next_poll.poll[n++] = current_poll.poll[i];
+ }
+ if(n == i){
+ printk("ignore_sigio_fd : fd %d not found\n", fd);
+ err = -1;
+ goto out;
+ }
+
+ update_thread();
+ out:
+ sigio_unlock();
+ return(err);
+}
+
+static struct pollfd *setup_initial_poll(int fd)
+{
+ struct pollfd *p;
+
+ p = um_kmalloc(sizeof(struct pollfd));
+ if (p == NULL) {
+ printk("setup_initial_poll : failed to allocate poll\n");
+ return NULL;
+ }
+ *p = ((struct pollfd) { .fd = fd,
+ .events = POLLIN,
+ .revents = 0 });
+ return p;
+}
+
+void write_sigio_workaround(void)
+{
+ unsigned long stack;
+ struct pollfd *p;
+ int err;
+ int l_write_sigio_fds[2];
+ int l_sigio_private[2];
+ int l_write_sigio_pid;
+
+ /* We call this *tons* of times - and most ones we must just fail. */
+ sigio_lock();
+ l_write_sigio_pid = write_sigio_pid;
+ sigio_unlock();
+
+ if (l_write_sigio_pid != -1)
+ return;
+
+ err = os_pipe(l_write_sigio_fds, 1, 1);
+ if(err < 0){
+ printk("write_sigio_workaround - os_pipe 1 failed, "
+ "err = %d\n", -err);
+ return;
+ }
+ err = os_pipe(l_sigio_private, 1, 1);
+ if(err < 0){
+ printk("write_sigio_workaround - os_pipe 2 failed, "
+ "err = %d\n", -err);
+ goto out_close1;
+ }
+
+ p = setup_initial_poll(l_sigio_private[1]);
+ if(!p)
+ goto out_close2;
+
+ sigio_lock();
+
+ /* Did we race? Don't try to optimize this, please, it's not so likely
+ * to happen, and no more than once at the boot. */
+ if(write_sigio_pid != -1)
+ goto out_unlock;
+
+ write_sigio_pid = run_helper_thread(write_sigio_thread, NULL,
+ CLONE_FILES | CLONE_VM, &stack, 0);
+
+ if (write_sigio_pid < 0)
+ goto out_clear;
+
+ if (write_sigio_irq(l_write_sigio_fds[0]))
+ goto out_kill;
+
+ /* Success, finally. */
+ memcpy(write_sigio_fds, l_write_sigio_fds, sizeof(l_write_sigio_fds));
+ memcpy(sigio_private, l_sigio_private, sizeof(l_sigio_private));
+
+ current_poll = ((struct pollfds) { .poll = p,
+ .used = 1,
+ .size = 1 });
+
+ sigio_unlock();
+ return;
+
+ out_kill:
+ l_write_sigio_pid = write_sigio_pid;
+ write_sigio_pid = -1;
+ sigio_unlock();
+ /* Going to call waitpid, avoid holding the lock. */
+ os_kill_process(l_write_sigio_pid, 1);
+ goto out_free;
+
+ out_clear:
+ write_sigio_pid = -1;
+ out_unlock:
+ sigio_unlock();
+ out_free:
+ kfree(p);
+ out_close2:
+ close(l_sigio_private[0]);
+ close(l_sigio_private[1]);
+ out_close1:
+ close(l_write_sigio_fds[0]);
+ close(l_write_sigio_fds[1]);
+ return;
+}
+
+void sigio_cleanup(void)
+{
+ if(write_sigio_pid != -1){
+ os_kill_process(write_sigio_pid, 1);
+ write_sigio_pid = -1;
+ }
+}
Index: linux-2.6.16/arch/um/kernel/sigio_user.c
===================================================================
--- linux-2.6.16.orig/arch/um/kernel/sigio_user.c 2006-03-23 17:25:36.000000000 -0500
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,324 +0,0 @@
-/*
- * Copyright (C) 2002 Jeff Dike ([email protected])
- * Licensed under the GPL
- */
-
-#include <unistd.h>
-#include <stdlib.h>
-#include <termios.h>
-#include <pty.h>
-#include <signal.h>
-#include <errno.h>
-#include <string.h>
-#include <sched.h>
-#include <sys/socket.h>
-#include <sys/poll.h>
-#include "init.h"
-#include "user.h"
-#include "kern_util.h"
-#include "user_util.h"
-#include "sigio.h"
-#include "os.h"
-
-/* Protected by sigio_lock(), also used by sigio_cleanup, which is an
- * exitcall.
- */
-static int write_sigio_pid = -1;
-
-/* These arrays are initialized before the sigio thread is started, and
- * the descriptors closed after it is killed. So, it can't see them change.
- * On the UML side, they are changed under the sigio_lock.
- */
-static int write_sigio_fds[2] = { -1, -1 };
-static int sigio_private[2] = { -1, -1 };
-
-struct pollfds {
- struct pollfd *poll;
- int size;
- int used;
-};
-
-/* Protected by sigio_lock(). Used by the sigio thread, but the UML thread
- * synchronizes with it.
- */
-struct pollfds current_poll = {
- .poll = NULL,
- .size = 0,
- .used = 0
-};
-
-struct pollfds next_poll = {
- .poll = NULL,
- .size = 0,
- .used = 0
-};
-
-static int write_sigio_thread(void *unused)
-{
- struct pollfds *fds, tmp;
- struct pollfd *p;
- int i, n, respond_fd;
- char c;
-
- signal(SIGWINCH, SIG_IGN);
- fds = &current_poll;
- while(1){
- n = poll(fds->poll, fds->used, -1);
- if(n < 0){
- if(errno == EINTR) continue;
- printk("write_sigio_thread : poll returned %d, "
- "errno = %d\n", n, errno);
- }
- for(i = 0; i < fds->used; i++){
- p = &fds->poll[i];
- if(p->revents == 0) continue;
- if(p->fd == sigio_private[1]){
- n = os_read_file(sigio_private[1], &c, sizeof(c));
- if(n != sizeof(c))
- printk("write_sigio_thread : "
- "read failed, err = %d\n", -n);
- tmp = current_poll;
- current_poll = next_poll;
- next_poll = tmp;
- respond_fd = sigio_private[1];
- }
- else {
- respond_fd = write_sigio_fds[1];
- fds->used--;
- memmove(&fds->poll[i], &fds->poll[i + 1],
- (fds->used - i) * sizeof(*fds->poll));
- }
-
- n = os_write_file(respond_fd, &c, sizeof(c));
- if(n != sizeof(c))
- printk("write_sigio_thread : write failed, "
- "err = %d\n", -n);
- }
- }
-
- return 0;
-}
-
-static int need_poll(int n)
-{
- if(n <= next_poll.size){
- next_poll.used = n;
- return(0);
- }
- kfree(next_poll.poll);
- next_poll.poll = um_kmalloc_atomic(n * sizeof(struct pollfd));
- if(next_poll.poll == NULL){
- printk("need_poll : failed to allocate new pollfds\n");
- next_poll.size = 0;
- next_poll.used = 0;
- return(-1);
- }
- next_poll.size = n;
- next_poll.used = n;
- return(0);
-}
-
-/* Must be called with sigio_lock held, because it's needed by the marked
- * critical section. */
-static void update_thread(void)
-{
- unsigned long flags;
- int n;
- char c;
-
- flags = set_signals(0);
- n = os_write_file(sigio_private[0], &c, sizeof(c));
- if(n != sizeof(c)){
- printk("update_thread : write failed, err = %d\n", -n);
- goto fail;
- }
-
- n = os_read_file(sigio_private[0], &c, sizeof(c));
- if(n != sizeof(c)){
- printk("update_thread : read failed, err = %d\n", -n);
- goto fail;
- }
-
- set_signals(flags);
- return;
- fail:
- /* Critical section start */
- if(write_sigio_pid != -1)
- os_kill_process(write_sigio_pid, 1);
- write_sigio_pid = -1;
- close(sigio_private[0]);
- close(sigio_private[1]);
- close(write_sigio_fds[0]);
- close(write_sigio_fds[1]);
- /* Critical section end */
- set_signals(flags);
-}
-
-int add_sigio_fd(int fd, int read)
-{
- int err = 0, i, n, events;
-
- sigio_lock();
- for(i = 0; i < current_poll.used; i++){
- if(current_poll.poll[i].fd == fd)
- goto out;
- }
-
- n = current_poll.used + 1;
- err = need_poll(n);
- if(err)
- goto out;
-
- for(i = 0; i < current_poll.used; i++)
- next_poll.poll[i] = current_poll.poll[i];
-
- if(read) events = POLLIN;
- else events = POLLOUT;
-
- next_poll.poll[n - 1] = ((struct pollfd) { .fd = fd,
- .events = events,
- .revents = 0 });
- update_thread();
- out:
- sigio_unlock();
- return(err);
-}
-
-int ignore_sigio_fd(int fd)
-{
- struct pollfd *p;
- int err = 0, i, n = 0;
-
- sigio_lock();
- for(i = 0; i < current_poll.used; i++){
- if(current_poll.poll[i].fd == fd) break;
- }
- if(i == current_poll.used)
- goto out;
-
- err = need_poll(current_poll.used - 1);
- if(err)
- goto out;
-
- for(i = 0; i < current_poll.used; i++){
- p = &current_poll.poll[i];
- if(p->fd != fd) next_poll.poll[n++] = current_poll.poll[i];
- }
- if(n == i){
- printk("ignore_sigio_fd : fd %d not found\n", fd);
- err = -1;
- goto out;
- }
-
- update_thread();
- out:
- sigio_unlock();
- return(err);
-}
-
-static struct pollfd* setup_initial_poll(int fd)
-{
- struct pollfd *p;
-
- p = um_kmalloc(sizeof(struct pollfd));
- if (p == NULL) {
- printk("setup_initial_poll : failed to allocate poll\n");
- return NULL;
- }
- *p = ((struct pollfd) { .fd = fd,
- .events = POLLIN,
- .revents = 0 });
- return p;
-}
-
-void write_sigio_workaround(void)
-{
- unsigned long stack;
- struct pollfd *p;
- int err;
- int l_write_sigio_fds[2];
- int l_sigio_private[2];
- int l_write_sigio_pid;
-
- /* We call this *tons* of times - and most ones we must just fail. */
- sigio_lock();
- l_write_sigio_pid = write_sigio_pid;
- sigio_unlock();
-
- if (l_write_sigio_pid != -1)
- return;
-
- err = os_pipe(l_write_sigio_fds, 1, 1);
- if(err < 0){
- printk("write_sigio_workaround - os_pipe 1 failed, "
- "err = %d\n", -err);
- return;
- }
- err = os_pipe(l_sigio_private, 1, 1);
- if(err < 0){
- printk("write_sigio_workaround - os_pipe 1 failed, "
- "err = %d\n", -err);
- goto out_close1;
- }
-
- p = setup_initial_poll(l_sigio_private[1]);
- if(!p)
- goto out_close2;
-
- sigio_lock();
-
- /* Did we race? Don't try to optimize this, please, it's not so likely
- * to happen, and no more than once at the boot. */
- if(write_sigio_pid != -1)
- goto out_unlock;
-
- write_sigio_pid = run_helper_thread(write_sigio_thread, NULL,
- CLONE_FILES | CLONE_VM, &stack, 0);
-
- if (write_sigio_pid < 0)
- goto out_clear;
-
- if (write_sigio_irq(l_write_sigio_fds[0]))
- goto out_kill;
-
- /* Success, finally. */
- memcpy(write_sigio_fds, l_write_sigio_fds, sizeof(l_write_sigio_fds));
- memcpy(sigio_private, l_sigio_private, sizeof(l_sigio_private));
-
- current_poll = ((struct pollfds) { .poll = p,
- .used = 1,
- .size = 1 });
-
- sigio_unlock();
- return;
-
- out_kill:
- l_write_sigio_pid = write_sigio_pid;
- write_sigio_pid = -1;
- sigio_unlock();
- /* Going to call waitpid, avoid holding the lock. */
- os_kill_process(l_write_sigio_pid, 1);
- goto out_free;
-
- out_clear:
- write_sigio_pid = -1;
- out_unlock:
- sigio_unlock();
- out_free:
- kfree(p);
- out_close2:
- close(l_sigio_private[0]);
- close(l_sigio_private[1]);
- out_close1:
- close(l_write_sigio_fds[0]);
- close(l_write_sigio_fds[1]);
- return;
-}
-
-void sigio_cleanup(void)
-{
- if (write_sigio_pid != -1) {
- os_kill_process(write_sigio_pid, 1);
- write_sigio_pid = -1;
- }
-}