diff options
Diffstat (limited to 'arch/um/os-Linux/signal.c')
-rw-r--r-- | arch/um/os-Linux/signal.c | 131 |
1 files changed, 62 insertions, 69 deletions
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c index b98f7ea..e9800b0 100644 --- a/arch/um/os-Linux/signal.c +++ b/arch/um/os-Linux/signal.c @@ -1,26 +1,21 @@ /* * Copyright (C) 2004 PathScale, Inc + * Copyright (C) 2004 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) * Licensed under the GPL */ -#include <signal.h> -#include <stdio.h> -#include <unistd.h> #include <stdlib.h> -#include <errno.h> #include <stdarg.h> -#include <string.h> -#include <sys/mman.h> -#include "user.h" -#include "signal_kern.h" -#include "sysdep/sigcontext.h" -#include "sysdep/barrier.h" -#include "sigcontext.h" -#include "mode.h" +#include <errno.h> +#include <signal.h> +#include <strings.h> #include "os.h" +#include "sysdep/barrier.h" +#include "sysdep/sigcontext.h" +#include "user.h" -/* These are the asynchronous signals. SIGVTALRM and SIGARLM are handled - * together under SIGVTALRM_BIT. SIGPROF is excluded because we want to +/* + * These are the asynchronous signals. SIGPROF is excluded because we want to * be able to profile all of UML, not just the non-critical sections. If * profiling is not thread-safe, then that is not my problem. We can disable * profiling when SMP is enabled in that case. @@ -31,10 +26,8 @@ #define SIGVTALRM_BIT 1 #define SIGVTALRM_MASK (1 << SIGVTALRM_BIT) -#define SIGALRM_BIT 2 -#define SIGALRM_MASK (1 << SIGALRM_BIT) - -/* These are used by both the signal handlers and +/* + * These are used by both the signal handlers and * block/unblock_signals. I don't want modifications cached in a * register - they must go straight to memory. */ @@ -46,34 +39,27 @@ void sig_handler(int sig, struct sigcontext *sc) int enabled; enabled = signals_enabled; - if(!enabled && (sig == SIGIO)){ + if (!enabled && (sig == SIGIO)) { pending |= SIGIO_MASK; return; } block_signals(); - CHOOSE_MODE_PROC(sig_handler_common_tt, sig_handler_common_skas, - sig, sc); + sig_handler_common_skas(sig, sc); set_signals(enabled); } -static void real_alarm_handler(int sig, struct sigcontext *sc) +static void real_alarm_handler(struct sigcontext *sc) { - union uml_pt_regs regs; + struct uml_pt_regs regs; - if(sig == SIGALRM) - switch_timers(0); - - if(sc != NULL) + if (sc != NULL) copy_sc(®s, sc); - regs.skas.is_user = 0; + regs.is_user = 0; unblock_signals(); - timer_handler(sig, ®s); - - if(sig == SIGALRM) - switch_timers(1); + timer_handler(SIGVTALRM, ®s); } void alarm_handler(int sig, struct sigcontext *sc) @@ -81,27 +67,30 @@ void alarm_handler(int sig, struct sigcontext *sc) int enabled; enabled = signals_enabled; - if(!signals_enabled){ - if(sig == SIGVTALRM) - pending |= SIGVTALRM_MASK; - else pending |= SIGALRM_MASK; - + if (!signals_enabled) { + pending |= SIGVTALRM_MASK; return; } block_signals(); - real_alarm_handler(sig, sc); + real_alarm_handler(sc); set_signals(enabled); } +void timer_init(void) +{ + set_handler(SIGVTALRM, (__sighandler_t) alarm_handler, + SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, -1); +} + void set_sigstack(void *sig_stack, int size) { stack_t stack = ((stack_t) { .ss_flags = 0, .ss_sp = (__ptr_t) sig_stack, .ss_size = size - sizeof(void *) }); - if(sigaltstack(&stack, NULL) != 0) + if (sigaltstack(&stack, NULL) != 0) panic("enabling signal stack failed, errno = %d\n", errno); } @@ -111,7 +100,7 @@ void remove_sigstack(void) .ss_sp = NULL, .ss_size = 0 }); - if(sigaltstack(&stack, NULL) != 0) + if (sigaltstack(&stack, NULL) != 0) panic("disabling signal stack failed, errno = %d\n", errno); } @@ -135,26 +124,27 @@ void handle_signal(int sig, struct sigcontext *sc) * with this interrupt. */ bail = to_irq_stack(&pending); - if(bail) + if (bail) return; nested = pending & 1; pending &= ~1; - while((sig = ffs(pending)) != 0){ + while ((sig = ffs(pending)) != 0){ sig--; pending &= ~(1 << sig); (*handlers[sig])(sig, sc); } - /* Again, pending comes back with a mask of signals + /* + * Again, pending comes back with a mask of signals * that arrived while tearing down the stack. If this * is non-zero, we just go back, set up the stack * again, and handle the new interrupts. */ - if(!nested) + if (!nested) pending = from_irq_stack(nested); - } while(pending); + } while (pending); } extern void hard_handler(int sig); @@ -172,18 +162,18 @@ void set_handler(int sig, void (*handler)(int), int flags, ...) sigemptyset(&action.sa_mask); va_start(ap, flags); - while((mask = va_arg(ap, int)) != -1) + while ((mask = va_arg(ap, int)) != -1) sigaddset(&action.sa_mask, mask); va_end(ap); action.sa_flags = flags; action.sa_restorer = NULL; - if(sigaction(sig, &action, NULL) < 0) + if (sigaction(sig, &action, NULL) < 0) panic("sigaction failed - errno = %d\n", errno); sigemptyset(&sig_mask); sigaddset(&sig_mask, sig); - if(sigprocmask(SIG_UNBLOCK, &sig_mask, NULL) < 0) + if (sigprocmask(SIG_UNBLOCK, &sig_mask, NULL) < 0) panic("sigprocmask failed - errno = %d\n", errno); } @@ -194,13 +184,14 @@ int change_sig(int signal, int on) sigemptyset(&sigset); sigaddset(&sigset, signal); sigprocmask(on ? SIG_UNBLOCK : SIG_BLOCK, &sigset, &old); - return(!sigismember(&old, signal)); + return !sigismember(&old, signal); } void block_signals(void) { signals_enabled = 0; - /* This must return with signals disabled, so this barrier + /* + * This must return with signals disabled, so this barrier * ensures that writes are flushed out before the return. * This might matter if gcc figures out how to inline this and * decides to shuffle this code into the caller. @@ -212,27 +203,31 @@ void unblock_signals(void) { int save_pending; - if(signals_enabled == 1) + if (signals_enabled == 1) return; - /* We loop because the IRQ handler returns with interrupts off. So, + /* + * We loop because the IRQ handler returns with interrupts off. So, * interrupts may have arrived and we need to re-enable them and * recheck pending. */ - while(1){ - /* Save and reset save_pending after enabling signals. This + while(1) { + /* + * Save and reset save_pending after enabling signals. This * way, pending won't be changed while we're reading it. */ signals_enabled = 1; - /* Setting signals_enabled and reading pending must + /* + * Setting signals_enabled and reading pending must * happen in this order. */ mb(); save_pending = pending; - if(save_pending == 0){ - /* This must return with signals enabled, so + if (save_pending == 0) { + /* + * This must return with signals enabled, so * this barrier ensures that writes are * flushed out before the return. This might * matter if gcc figures out how to inline @@ -245,26 +240,24 @@ void unblock_signals(void) pending = 0; - /* We have pending interrupts, so disable signals, as the + /* + * We have pending interrupts, so disable signals, as the * handlers expect them off when they are called. They will * be enabled again above. */ signals_enabled = 0; - /* Deal with SIGIO first because the alarm handler might + /* + * Deal with SIGIO first because the alarm handler might * schedule, leaving the pending SIGIO stranded until we come * back here. */ - if(save_pending & SIGIO_MASK) - CHOOSE_MODE_PROC(sig_handler_common_tt, - sig_handler_common_skas, SIGIO, NULL); - - if(save_pending & SIGALRM_MASK) - real_alarm_handler(SIGALRM, NULL); + if (save_pending & SIGIO_MASK) + sig_handler_common_skas(SIGIO, NULL); - if(save_pending & SIGVTALRM_MASK) - real_alarm_handler(SIGVTALRM, NULL); + if (save_pending & SIGVTALRM_MASK) + real_alarm_handler(NULL); } } @@ -276,11 +269,11 @@ int get_signals(void) int set_signals(int enable) { int ret; - if(signals_enabled == enable) + if (signals_enabled == enable) return enable; ret = signals_enabled; - if(enable) + if (enable) unblock_signals(); else block_signals(); |