From f206aabb035318ac4bafbf0b87798335de3634df Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Mon, 27 Mar 2006 01:14:33 -0800 Subject: [PATCH] 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 Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/kernel/Makefile | 2 +- arch/um/kernel/sigio_user.c | 324 -------------------------------------------- 2 files changed, 1 insertion(+), 325 deletions(-) delete mode 100644 arch/um/kernel/sigio_user.c (limited to 'arch/um/kernel') diff --git a/arch/um/kernel/Makefile b/arch/um/kernel/Makefile index 8458c30a6265..ac5afaa0306f 100644 --- a/arch/um/kernel/Makefile +++ b/arch/um/kernel/Makefile @@ -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 diff --git a/arch/um/kernel/sigio_user.c b/arch/um/kernel/sigio_user.c deleted file mode 100644 index 9bef9413cb5d..000000000000 --- a/arch/um/kernel/sigio_user.c +++ /dev/null @@ -1,324 +0,0 @@ -/* - * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) - * Licensed under the GPL - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#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 = ¤t_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 = ¤t_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; - } -} -- cgit v1.2.3-59-g8ed1b