From 151fd6acd94e12ef3a7d5fa0911a2590690c493f Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Thu, 15 Feb 2007 11:40:37 +0000 Subject: [MIPS] signals: Share even more code. native and compat do_signal and handle_signal are identical and can easily be unified. Signed-off-by: Ralf Baechle --- arch/mips/kernel/signal.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) (limited to 'arch/mips/kernel/signal.c') diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index b2e9ab1..adbfb95 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -398,7 +398,7 @@ badframe: } #ifdef CONFIG_TRAD_SIGNALS -int setup_frame(struct k_sigaction * ka, struct pt_regs *regs, +static int setup_frame(struct k_sigaction * ka, struct pt_regs *regs, int signr, sigset_t *set) { struct sigframe __user *frame; @@ -443,7 +443,7 @@ give_sigsegv: } #endif -int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs, +static int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs, int signr, sigset_t *set, siginfo_t *info) { struct rt_sigframe __user *frame; @@ -501,6 +501,14 @@ give_sigsegv: return -EFAULT; } +struct mips_abi mips_abi = { +#ifdef CONFIG_TRAD_SIGNALS + .setup_frame = setup_frame, +#endif + .setup_rt_frame = setup_rt_frame, + .restart = __NR_restart_syscall +}; + static int handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs) { @@ -539,7 +547,7 @@ static int handle_signal(unsigned long sig, siginfo_t *info, return ret; } -void do_signal(struct pt_regs *regs) +static void do_signal(struct pt_regs *regs) { struct k_sigaction ka; sigset_t *oldset; @@ -589,7 +597,7 @@ void do_signal(struct pt_regs *regs) regs->cp0_epc -= 8; } if (regs->regs[2] == ERESTART_RESTARTBLOCK) { - regs->regs[2] = __NR_restart_syscall; + regs->regs[2] = current->thread.abi->restart; regs->regs[7] = regs->regs[26]; regs->cp0_epc -= 4; } @@ -615,5 +623,5 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused, { /* deal with pending signal delivery */ if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) - current->thread.abi->do_signal(regs); + do_signal(regs); } -- cgit v1.1 From 9693a85378b590cc7a4aa2db2174422585c7c8c4 Mon Sep 17 00:00:00 2001 From: Franck Bui-Huu Date: Fri, 2 Feb 2007 17:41:47 +0100 Subject: [MIPS] Add basic SMARTMIPS ASE support This patch adds trivial support for SMARTMIPS extension. This extension is currently implemented by 4KS[CD] CPUs. Basically it saves/restores ACX register, which is part of the SMARTMIPS ASE, when needed. This patch does *not* add any support for Smartmips MMU features. Futhermore this patch does not add explicit support for 4KS[CD] CPUs since they are respectively mips32 and mips32r2 compliant. So with the current processor configuration, a platform that has such CPUs needs to select both configs: CPU_HAS_SMARTMIPS SYS_HAS_CPU_MIPS32_R[12] This is due to the processor configuration which is mixing up all the architecture variants and the processor types. The drawback of this, is that we currently pass '-march=mips32' option to gcc when building a kernel instead of '-march=4ksc' for 4KSC case. This can lead to a kernel image a little bit bigger than required. Signed-off-by: Franck Bui-Huu Signed-off-by: Ralf Baechle --- arch/mips/kernel/signal.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch/mips/kernel/signal.c') diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index adbfb95..f091786 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -89,6 +89,9 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) for (i = 1; i < 32; i++) err |= __put_user(regs->regs[i], &sc->sc_regs[i]); +#ifdef CONFIG_CPU_HAS_SMARTMIPS + err |= __put_user(regs->acx, &sc->sc_acx); +#endif err |= __put_user(regs->hi, &sc->sc_mdhi); err |= __put_user(regs->lo, &sc->sc_mdlo); if (cpu_has_dsp) { @@ -132,6 +135,10 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) current_thread_info()->restart_block.fn = do_no_restart_syscall; err |= __get_user(regs->cp0_epc, &sc->sc_pc); + +#ifdef CONFIG_CPU_HAS_SMARTMIPS + err |= __get_user(regs->acx, &sc->sc_acx); +#endif err |= __get_user(regs->hi, &sc->sc_mdhi); err |= __get_user(regs->lo, &sc->sc_mdlo); if (cpu_has_dsp) { -- cgit v1.1 From c6a2f4679331206ef5d353fc9a6cda2fa4aef8c6 Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Sat, 10 Mar 2007 01:03:48 +0900 Subject: [MIPS] Check FCSR for pending interrupts, alternative version Commit 6d6671066a311703bca1b91645bb1e04cc983387 is incomplete and misses non-r4k CPUs. This patch reverts the commit and fixes in other way. o Do FCSR checking in caller of restore_fp_context. o Send SIGFPE if the signal handler set any FPU exception bits. Signed-off-by: Atsushi Nemoto Signed-off-by: Ralf Baechle --- arch/mips/kernel/signal.c | 46 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 43 insertions(+), 3 deletions(-) (limited to 'arch/mips/kernel/signal.c') diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index f091786..bf094fc 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -124,6 +124,37 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) return err; } +int fpcsr_pending(unsigned int __user *fpcsr) +{ + int err, sig = 0; + unsigned int csr, enabled; + + err = __get_user(csr, fpcsr); + enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5); + /* + * If the signal handler set some FPU exceptions, clear it and + * send SIGFPE. + */ + if (csr & enabled) { + csr &= ~enabled; + err |= __put_user(csr, fpcsr); + sig = SIGFPE; + } + return err ?: sig; +} + +static int +check_and_restore_fp_context(struct sigcontext __user *sc) +{ + int err, sig; + + err = sig = fpcsr_pending(&sc->sc_fpc_csr); + if (err > 0) + err = 0; + err |= restore_fp_context(sc); + return err ?: sig; +} + int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) { unsigned int used_math; @@ -162,7 +193,8 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) if (used_math()) { /* restore fpu context if we have used it before */ own_fpu(); - err |= restore_fp_context(sc); + if (!err) + err = check_and_restore_fp_context(sc); } else { /* signal handler may have used FPU. Give it up. */ lose_fpu(); @@ -332,6 +364,7 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs) { struct sigframe __user *frame; sigset_t blocked; + int sig; frame = (struct sigframe __user *) regs.regs[29]; if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) @@ -345,8 +378,11 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs) recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - if (restore_sigcontext(®s, &frame->sf_sc)) + sig = restore_sigcontext(®s, &frame->sf_sc); + if (sig < 0) goto badframe; + else if (sig) + force_sig(sig, current); /* * Don't let your children do this ... @@ -368,6 +404,7 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs) struct rt_sigframe __user *frame; sigset_t set; stack_t st; + int sig; frame = (struct rt_sigframe __user *) regs.regs[29]; if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) @@ -381,8 +418,11 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs) recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - if (restore_sigcontext(®s, &frame->rs_uc.uc_mcontext)) + sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext); + if (sig < 0) goto badframe; + else if (sig) + force_sig(sig, current); if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st))) goto badframe; -- cgit v1.1 From 53dc80287da43b75df2fe2658651d3c5160dad8e Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Sat, 10 Mar 2007 01:07:45 +0900 Subject: [MIPS] FPU ownership management & preemption fixes Signed-off-by: Atsushi Nemoto Signed-off-by: Ralf Baechle --- arch/mips/kernel/signal.c | 29 ++++++++++++----------------- 1 file changed, 12 insertions(+), 17 deletions(-) (limited to 'arch/mips/kernel/signal.c') diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index bf094fc..8c3c5a5 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -82,6 +82,7 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) { int err = 0; int i; + unsigned int used_math; err |= __put_user(regs->cp0_epc, &sc->sc_pc); @@ -104,22 +105,18 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp); } - err |= __put_user(!!used_math(), &sc->sc_used_math); + used_math = !!used_math(); + err |= __put_user(used_math, &sc->sc_used_math); - if (used_math()) { + if (used_math) { /* * Save FPU state to signal context. Signal handler * will "inherit" current FPU state. */ - preempt_disable(); - - if (!is_fpu_owner()) { - own_fpu(); - restore_fp(current); - } + own_fpu(1); + enable_fp_in_kernel(); err |= save_fp_context(sc); - - preempt_enable(); + disable_fp_in_kernel(); } return err; } @@ -188,20 +185,18 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) err |= __get_user(used_math, &sc->sc_used_math); conditional_used_math(used_math); - preempt_disable(); - - if (used_math()) { + if (used_math) { /* restore fpu context if we have used it before */ - own_fpu(); + own_fpu(0); + enable_fp_in_kernel(); if (!err) err = check_and_restore_fp_context(sc); + disable_fp_in_kernel(); } else { /* signal handler may have used FPU. Give it up. */ - lose_fpu(); + lose_fpu(0); } - preempt_enable(); - return err; } -- cgit v1.1 From 5323180db75d562a287cb2020b07c9422df13df6 Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Sat, 14 Apr 2007 02:37:26 +0900 Subject: [MIPS] Disallow CpU exception in kernel again. The commit 4d40bff7110e9e1a97ff8c01bdd6350e9867cc10 ("Allow CpU exception in kernel partially") was broken. The commit was to fix theoretical problem but broke usual case. Revert it for now. Signed-off-by: Atsushi Nemoto Signed-off-by: Ralf Baechle --- arch/mips/kernel/signal.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'arch/mips/kernel/signal.c') diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index 8c3c5a5..fa58119 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -113,10 +113,10 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) * Save FPU state to signal context. Signal handler * will "inherit" current FPU state. */ + preempt_disable(); own_fpu(1); - enable_fp_in_kernel(); err |= save_fp_context(sc); - disable_fp_in_kernel(); + preempt_enable(); } return err; } @@ -148,7 +148,10 @@ check_and_restore_fp_context(struct sigcontext __user *sc) err = sig = fpcsr_pending(&sc->sc_fpc_csr); if (err > 0) err = 0; + preempt_disable(); + own_fpu(0); err |= restore_fp_context(sc); + preempt_enable(); return err ?: sig; } @@ -187,11 +190,8 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) if (used_math) { /* restore fpu context if we have used it before */ - own_fpu(0); - enable_fp_in_kernel(); if (!err) err = check_and_restore_fp_context(sc); - disable_fp_in_kernel(); } else { /* signal handler may have used FPU. Give it up. */ lose_fpu(0); -- cgit v1.1 From faea62346444ce5b1dba8fb5291d95b676522c42 Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Mon, 16 Apr 2007 23:19:44 +0900 Subject: [MIPS] Retry {save,restore}_fp_context if failed in atomic context. The save_fp_context()/restore_fp_context() might sleep on accessing user stack and therefore might lose FPU ownership in middle of them. If these function failed due to "in_atomic" test in do_page_fault, touch the sigcontext area in non-atomic context and retry these save/restore operation. This is a replacement of a (broken) fix which was titled "Allow CpU exception in kernel partially". Signed-off-by: Atsushi Nemoto Signed-off-by: Ralf Baechle --- arch/mips/kernel/signal.c | 52 +++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 43 insertions(+), 9 deletions(-) (limited to 'arch/mips/kernel/signal.c') diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index fa58119..07d6730 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include @@ -27,7 +28,6 @@ #include #include #include -#include #include #include #include @@ -78,6 +78,46 @@ struct rt_sigframe { /* * Helper routines */ +static int protected_save_fp_context(struct sigcontext __user *sc) +{ + int err; + while (1) { + lock_fpu_owner(); + own_fpu_inatomic(1); + err = save_fp_context(sc); /* this might fail */ + unlock_fpu_owner(); + if (likely(!err)) + break; + /* touch the sigcontext and try again */ + err = __put_user(0, &sc->sc_fpregs[0]) | + __put_user(0, &sc->sc_fpregs[31]) | + __put_user(0, &sc->sc_fpc_csr); + if (err) + break; /* really bad sigcontext */ + } + return err; +} + +static int protected_restore_fp_context(struct sigcontext __user *sc) +{ + int err, tmp; + while (1) { + lock_fpu_owner(); + own_fpu_inatomic(0); + err = restore_fp_context(sc); /* this might fail */ + unlock_fpu_owner(); + if (likely(!err)) + break; + /* touch the sigcontext and try again */ + err = __get_user(tmp, &sc->sc_fpregs[0]) | + __get_user(tmp, &sc->sc_fpregs[31]) | + __get_user(tmp, &sc->sc_fpc_csr); + if (err) + break; /* really bad sigcontext */ + } + return err; +} + int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) { int err = 0; @@ -113,10 +153,7 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) * Save FPU state to signal context. Signal handler * will "inherit" current FPU state. */ - preempt_disable(); - own_fpu(1); - err |= save_fp_context(sc); - preempt_enable(); + err |= protected_save_fp_context(sc); } return err; } @@ -148,10 +185,7 @@ check_and_restore_fp_context(struct sigcontext __user *sc) err = sig = fpcsr_pending(&sc->sc_fpc_csr); if (err > 0) err = 0; - preempt_disable(); - own_fpu(0); - err |= restore_fp_context(sc); - preempt_enable(); + err |= protected_restore_fp_context(sc); return err ?: sig; } -- cgit v1.1