From 574852a2a5cb603708133ade9896c9bc77a68c46 Mon Sep 17 00:00:00 2001 From: Jesper Nilsson Date: Fri, 25 Jan 2008 16:10:02 +0100 Subject: [PATCH] CRIS v32: Update signal handling in kernel/signal.c - do_signal now returns void, and does not have the previous signal set as a parameter. - Remove sys_rt_sigsuspend, we can use the common one instead. - Change sys_sigsuspend to be more like x86, don't call do_signal here. - handle_signal, setup_frame and setup_rt_frame now return -EFAULT if we've delivered a segfault, which is used by callers to perform necessary cleanup. - Break long lines, correct whitespace and formatting errors. --- arch/cris/arch-v32/kernel/signal.c | 144 +++++++++++------------------ 1 file changed, 56 insertions(+), 88 deletions(-) diff --git a/arch/cris/arch-v32/kernel/signal.c b/arch/cris/arch-v32/kernel/signal.c index 024cc69019..58c1866804 100644 --- a/arch/cris/arch-v32/kernel/signal.c +++ b/arch/cris/arch-v32/kernel/signal.c @@ -50,7 +50,7 @@ struct rt_signal_frame { unsigned char retcode[8]; /* Trampoline code. */ }; -int do_signal(int restart, sigset_t *oldset, struct pt_regs *regs); +void do_signal(int restart, struct pt_regs *regs); void keep_debug_flags(unsigned long oldccs, unsigned long oldspc, struct pt_regs *regs); /* @@ -61,74 +61,16 @@ int sys_sigsuspend(old_sigset_t mask, long r11, long r12, long r13, long mof, long srp, struct pt_regs *regs) { - sigset_t saveset; - mask &= _BLOCKABLE; - spin_lock_irq(¤t->sighand->siglock); - - saveset = current->blocked; - + current->saved_sigmask = current->blocked; siginitset(¤t->blocked, mask); - - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - regs->r10 = -EINTR; - - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - - if (do_signal(0, &saveset, regs)) { - /* - * This point is reached twice: once to call - * the signal handler, then again to return - * from the sigsuspend system call. When - * calling the signal handler, R10 hold the - * signal number as set by do_signal(). The - * sigsuspend call will always return with - * the restored value above; -EINTR. - */ - return regs->r10; - } - } -} - -/* Define some dummy arguments to be able to reach the regs argument. */ -int -sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, long r12, long r13, - long mof, long srp, struct pt_regs *regs) -{ - sigset_t saveset; - sigset_t newset; - - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (copy_from_user(&newset, unewset, sizeof(newset))) - return -EFAULT; - - sigdelsetmask(&newset, ~_BLOCKABLE); - spin_lock_irq(¤t->sighand->siglock); - - saveset = current->blocked; - current->blocked = newset; - recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - - regs->r10 = -EINTR; - - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - - if (do_signal(0, &saveset, regs)) { - /* See comment in function above. */ - return regs->r10; - } - } + current->state = TASK_INTERRUPTIBLE; + schedule(); + set_thread_flag(TIF_RESTORE_SIGMASK); + return -ERESTARTNOHAND; } int @@ -290,7 +232,7 @@ sys_rt_sigreturn(long r10, long r11, long r12, long r13, long mof, long srp, goto badframe; if (do_sigaltstack(&frame->uc.uc_stack, NULL, rdusp()) == -EFAULT) - goto badframe; + goto badframe; keep_debug_flags(oldccs, oldspc, regs); @@ -347,11 +289,11 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) /* Grab and setup a signal frame. * * Basically a lot of state-info is stacked, and arranged for the - * user-mode program to return to the kernel using either a trampoline + * user-mode program to return to the kernel using either a trampiline * which performs the syscall sigreturn(), or a provided user-mode * trampoline. */ -static void +static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, struct pt_regs * regs) { @@ -417,16 +359,17 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, /* Actually move the USP to reflect the stacked frame. */ wrusp((unsigned long)frame); - return; + return 0; give_sigsegv: if (sig == SIGSEGV) ka->sa.sa_handler = SIG_DFL; force_sig(SIGSEGV, current); + return -EFAULT; } -static void +static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *set, struct pt_regs * regs) { @@ -503,21 +446,24 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, /* Actually move the usp to reflect the stacked frame. */ wrusp((unsigned long)frame); - return; + return 0; give_sigsegv: if (sig == SIGSEGV) ka->sa.sa_handler = SIG_DFL; force_sig(SIGSEGV, current); + return -EFAULT; } /* Invoke a singal handler to, well, handle the signal. */ -static inline void +static inline int handle_signal(int canrestart, unsigned long sig, siginfo_t *info, struct k_sigaction *ka, sigset_t *oldset, struct pt_regs * regs) { + int ret; + /* Check if this got called from a system call. */ if (canrestart) { /* If so, check system call restarting. */ @@ -561,19 +507,24 @@ handle_signal(int canrestart, unsigned long sig, /* Set up the stack frame. */ if (ka->sa.sa_flags & SA_SIGINFO) - setup_rt_frame(sig, ka, info, oldset, regs); + ret = setup_rt_frame(sig, ka, info, oldset, regs); else - setup_frame(sig, ka, oldset, regs); + ret = setup_frame(sig, ka, oldset, regs); if (ka->sa.sa_flags & SA_ONESHOT) ka->sa.sa_handler = SIG_DFL; - spin_lock_irq(¤t->sighand->siglock); - sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); - if (!(ka->sa.sa_flags & SA_NODEFER)) - sigaddset(¤t->blocked,sig); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); + if (ret == 0) { + spin_lock_irq(¤t->sighand->siglock); + sigorsets(¤t->blocked, ¤t->blocked, + &ka->sa.sa_mask); + if (!(ka->sa.sa_flags & SA_NODEFER)) + sigaddset(¤t->blocked, sig); + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + } + + return ret; } /* @@ -587,12 +538,13 @@ handle_signal(int canrestart, unsigned long sig, * we can use user_mode(regs) to see if we came directly from kernel or user * mode below. */ -int -do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs) +void +do_signal(int canrestart, struct pt_regs *regs) { int signr; siginfo_t info; struct k_sigaction ka; + sigset_t *oldset; /* * The common case should go fast, which is why this point is @@ -600,17 +552,28 @@ do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs) * without doing anything. */ if (!user_mode(regs)) - return 1; + return; - if (!oldset) + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + oldset = ¤t->saved_sigmask; + else oldset = ¤t->blocked; signr = get_signal_to_deliver(&info, &ka, regs, NULL); if (signr > 0) { - /* Deliver the signal. */ - handle_signal(canrestart, signr, &info, &ka, oldset, regs); - return 1; + /* Whee! Actually deliver the signal. */ + if (handle_signal(canrestart, signr, &info, &ka, + oldset, regs)) { + /* a signal was successfully delivered; the saved + * sigmask will have been stored in the signal frame, + * and will be restored by sigreturn, so we can simply + * clear the TIF_RESTORE_SIGMASK flag */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + clear_thread_flag(TIF_RESTORE_SIGMASK); + } + + return; } /* Got here from a system call? */ @@ -628,7 +591,12 @@ do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs) } } - return 0; + /* if there's no signal to deliver, we just put the saved sigmask + * back */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) { + clear_thread_flag(TIF_RESTORE_SIGMASK); + sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); + } } asmlinkage void @@ -641,7 +609,7 @@ ugdb_trap_user(struct thread_info *ti, int sig) user_regs(ti)->spc = 0; } /* FIXME: Filter out false h/w breakpoint hits (i.e. EDA - not within any configured h/w breakpoint range). Synchronize with + not withing any configured h/w breakpoint range). Synchronize with what already exists for kernel debugging. */ if (((user_regs(ti)->exs & 0xff00) >> 8) == BREAK_8_INTR_VECT) { /* Break 8: subtract 2 from ERP unless in a delay slot. */ -- 2.39.5