diff options
Diffstat (limited to 'arch/csky')
-rw-r--r-- | arch/csky/abiv1/inc/abi/entry.h | 7 | ||||
-rw-r--r-- | arch/csky/abiv1/inc/abi/regdef.h | 2 | ||||
-rw-r--r-- | arch/csky/abiv2/inc/abi/entry.h | 7 | ||||
-rw-r--r-- | arch/csky/abiv2/inc/abi/regdef.h | 2 | ||||
-rw-r--r-- | arch/csky/kernel/atomic.S | 26 | ||||
-rw-r--r-- | arch/csky/kernel/entry.S | 37 | ||||
-rw-r--r-- | arch/csky/kernel/signal.c | 343 |
7 files changed, 150 insertions, 274 deletions
diff --git a/arch/csky/abiv1/inc/abi/entry.h b/arch/csky/abiv1/inc/abi/entry.h index 7dacce4c0f15..4a485b142be1 100644 --- a/arch/csky/abiv1/inc/abi/entry.h +++ b/arch/csky/abiv1/inc/abi/entry.h @@ -16,9 +16,6 @@ #define LSAVE_A4 40 #define LSAVE_A5 44 -#define EPC_INCREASE 2 -#define EPC_KEEP 0 - .macro USPTOKSP mtcr sp, ss1 mfcr sp, ss0 @@ -29,10 +26,6 @@ mfcr sp, ss1 .endm -.macro INCTRAP rx - addi \rx, EPC_INCREASE -.endm - .macro SAVE_ALL epc_inc mtcr r13, ss2 mfcr r13, epsr diff --git a/arch/csky/abiv1/inc/abi/regdef.h b/arch/csky/abiv1/inc/abi/regdef.h index 9e7e692dd271..729b1c3edcfd 100644 --- a/arch/csky/abiv1/inc/abi/regdef.h +++ b/arch/csky/abiv1/inc/abi/regdef.h @@ -21,4 +21,6 @@ #define SYSTRACE_SAVENUM 2 +#define TRAP0_SIZE 2 + #endif /* __ASM_CSKY_REGDEF_H */ diff --git a/arch/csky/abiv2/inc/abi/entry.h b/arch/csky/abiv2/inc/abi/entry.h index ea376ed716c4..6a0df655182c 100644 --- a/arch/csky/abiv2/inc/abi/entry.h +++ b/arch/csky/abiv2/inc/abi/entry.h @@ -14,18 +14,11 @@ #define LSAVE_A2 32 #define LSAVE_A3 36 -#define EPC_INCREASE 4 -#define EPC_KEEP 0 - #define KSPTOUSP #define USPTOKSP #define usp cr<14, 1> -.macro INCTRAP rx - addi \rx, EPC_INCREASE -.endm - .macro SAVE_ALL epc_inc subi sp, 152 stw tls, (sp, 0) diff --git a/arch/csky/abiv2/inc/abi/regdef.h b/arch/csky/abiv2/inc/abi/regdef.h index 652f5ce4c3dd..77cb1788b04c 100644 --- a/arch/csky/abiv2/inc/abi/regdef.h +++ b/arch/csky/abiv2/inc/abi/regdef.h @@ -21,4 +21,6 @@ #define SYSTRACE_SAVENUM 5 +#define TRAP0_SIZE 4 + #endif /* __ASM_CSKY_REGDEF_H */ diff --git a/arch/csky/kernel/atomic.S b/arch/csky/kernel/atomic.S index d2357c8f85bd..5b84f11485ae 100644 --- a/arch/csky/kernel/atomic.S +++ b/arch/csky/kernel/atomic.S @@ -12,11 +12,10 @@ * If *ptr != oldval && return 1, * else *ptr = newval return 0. */ -#ifdef CONFIG_CPU_HAS_LDSTEX ENTRY(csky_cmpxchg) USPTOKSP mfcr a3, epc - INCTRAP a3 + addi a3, TRAP0_SIZE subi sp, 8 stw a3, (sp, 0) @@ -24,6 +23,7 @@ ENTRY(csky_cmpxchg) stw a3, (sp, 4) psrset ee +#ifdef CONFIG_CPU_HAS_LDSTEX 1: ldex a3, (a2) cmpne a0, a3 @@ -33,27 +33,7 @@ ENTRY(csky_cmpxchg) bez a3, 1b 2: sync.is - mvc a0 - ldw a3, (sp, 0) - mtcr a3, epc - ldw a3, (sp, 4) - mtcr a3, epsr - addi sp, 8 - KSPTOUSP - rte -END(csky_cmpxchg) #else -ENTRY(csky_cmpxchg) - USPTOKSP - mfcr a3, epc - INCTRAP a3 - - subi sp, 8 - stw a3, (sp, 0) - mfcr a3, epsr - stw a3, (sp, 4) - - psrset ee 1: ldw a3, (a2) cmpne a0, a3 @@ -61,6 +41,7 @@ ENTRY(csky_cmpxchg) 2: stw a1, (a2) 3: +#endif mvc a0 ldw a3, (sp, 0) mtcr a3, epc @@ -71,6 +52,7 @@ ENTRY(csky_cmpxchg) rte END(csky_cmpxchg) +#ifndef CONFIG_CPU_HAS_LDSTEX /* * Called from tlbmodified exception */ diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S index b3b3b0bbfcc7..c0f80736dac6 100644 --- a/arch/csky/kernel/entry.S +++ b/arch/csky/kernel/entry.S @@ -91,7 +91,7 @@ ENTRY(csky_\name) mfcr a3, ss2 mfcr r6, ss3 mfcr a2, ss4 - SAVE_ALL EPC_KEEP + SAVE_ALL 0 .endm .macro tlbop_end is_write RD_MEH a2 @@ -117,7 +117,7 @@ jbsr csky_cmpxchg_fixup tlbop_end 1 ENTRY(csky_systemcall) - SAVE_ALL EPC_INCREASE + SAVE_ALL TRAP0_SIZE psrset ee, ie @@ -190,11 +190,9 @@ ENTRY(ret_from_fork) ldw r8, (r9, TINFO_FLAGS) ANDI_R3 r8, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT) cmpnei r8, 0 - bf 3f + bf ret_from_exception mov a0, sp /* sp = pt_regs pointer */ jbsr syscall_trace_exit -3: - jbsr ret_from_exception ret_from_exception: ld syscallid, (sp, LSAVE_PSR) @@ -209,34 +207,29 @@ ret_from_exception: bmaski r10, THREAD_SHIFT andn r9, r10 -resume_userspace: ldw r8, (r9, TINFO_FLAGS) andi r8, (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED) cmpnei r8, 0 bt exit_work -1: RESTORE_ALL +1: + RESTORE_ALL exit_work: + lrw syscallid, ret_from_exception + mov lr, syscallid + btsti r8, TIF_NEED_RESCHED bt work_resched - /* If thread_info->flag is empty, RESTORE_ALL */ - cmpnei r8, 0 - bf 1b - mov a0, r8 - mov a1, sp - jbsr do_notify_resume /* do signals */ - br resume_userspace + + mov a0, sp + mov a1, r8 + jmpi do_notify_resume work_resched: - lrw syscallid, ret_from_exception - mov r15, syscallid /* Return address in link */ jmpi schedule -ENTRY(sys_rt_sigreturn) - jmpi do_rt_sigreturn - ENTRY(csky_trap) - SAVE_ALL EPC_KEEP + SAVE_ALL 0 psrset ee mov a0, sp /* Push Stack pointer arg */ jbsr trap_c /* Call C-level trap handler */ @@ -252,7 +245,7 @@ ENTRY(csky_get_tls) /* increase epc for continue */ mfcr a0, epc - INCTRAP a0 + addi a0, TRAP0_SIZE mtcr a0, epc /* get current task thread_info with kernel 8K stack */ @@ -269,7 +262,7 @@ ENTRY(csky_get_tls) rte ENTRY(csky_irq) - SAVE_ALL EPC_KEEP + SAVE_ALL 0 psrset ee #ifdef CONFIG_PREEMPT diff --git a/arch/csky/kernel/signal.c b/arch/csky/kernel/signal.c index 5a18940f0b09..04a43cfd4e09 100644 --- a/arch/csky/kernel/signal.c +++ b/arch/csky/kernel/signal.c @@ -1,26 +1,10 @@ // SPDX-License-Identifier: GPL-2.0 -// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/kernel.h> #include <linux/signal.h> +#include <linux/uaccess.h> #include <linux/syscalls.h> -#include <linux/errno.h> -#include <linux/wait.h> -#include <linux/ptrace.h> -#include <linux/unistd.h> -#include <linux/stddef.h> -#include <linux/highuid.h> -#include <linux/personality.h> -#include <linux/tty.h> -#include <linux/binfmts.h> #include <linux/tracehook.h> -#include <linux/freezer.h> -#include <linux/uaccess.h> -#include <asm/setup.h> -#include <asm/pgtable.h> #include <asm/traps.h> #include <asm/ucontext.h> #include <asm/vdso.h> @@ -29,110 +13,117 @@ #ifdef CONFIG_CPU_HAS_FPU #include <abi/fpu.h> - -static int restore_fpu_state(struct sigcontext *sc) +static int restore_fpu_state(struct sigcontext __user *sc) { int err = 0; struct user_fp user_fp; - err = copy_from_user(&user_fp, &sc->sc_user_fp, sizeof(user_fp)); + err = __copy_from_user(&user_fp, &sc->sc_user_fp, sizeof(user_fp)); restore_from_user_fp(&user_fp); return err; } -static int save_fpu_state(struct sigcontext *sc) +static int save_fpu_state(struct sigcontext __user *sc) { struct user_fp user_fp; save_to_user_fp(&user_fp); - return copy_to_user(&sc->sc_user_fp, &user_fp, sizeof(user_fp)); + return __copy_to_user(&sc->sc_user_fp, &user_fp, sizeof(user_fp)); } #else -static inline int restore_fpu_state(struct sigcontext *sc) { return 0; } -static inline int save_fpu_state(struct sigcontext *sc) { return 0; } +#define restore_fpu_state(sigcontext) (0) +#define save_fpu_state(sigcontext) (0) #endif struct rt_sigframe { - int sig; - struct siginfo *pinfo; - void *puc; struct siginfo info; struct ucontext uc; }; -static int -restore_sigframe(struct pt_regs *regs, - struct sigcontext *sc, int *pr2) +static long restore_sigcontext(struct pt_regs *regs, + struct sigcontext __user *sc) { int err = 0; - /* Always make any pending restarted system calls return -EINTR */ - current_thread_info()->task->restart_block.fn = do_no_restart_syscall; - - err |= copy_from_user(regs, &sc->sc_pt_regs, sizeof(struct pt_regs)); + /* sc_pt_regs is structured the same as the start of pt_regs */ + err |= __copy_from_user(regs, &sc->sc_pt_regs, sizeof(struct pt_regs)); + /* Restore the floating-point state. */ err |= restore_fpu_state(sc); - *pr2 = regs->a0; return err; } -asmlinkage int -do_rt_sigreturn(void) +SYSCALL_DEFINE0(rt_sigreturn) { - sigset_t set; - int a0; struct pt_regs *regs = current_pt_regs(); - struct rt_sigframe *frame = (struct rt_sigframe *)(regs->usp); + struct rt_sigframe __user *frame; + struct task_struct *task; + sigset_t set; + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + + frame = (struct rt_sigframe __user *)regs->usp; if (!access_ok(frame, sizeof(*frame))) goto badframe; + if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) goto badframe; - sigdelsetmask(&set, (sigmask(SIGKILL) | sigmask(SIGSTOP))); - spin_lock_irq(¤t->sighand->siglock); - current->blocked = set; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); + set_current_blocked(&set); + + if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) + goto badframe; - if (restore_sigframe(regs, &frame->uc.uc_mcontext, &a0)) + if (restore_altstack(&frame->uc.uc_stack)) goto badframe; - return a0; + return regs->a0; badframe: - force_sig(SIGSEGV, current); + task = current; + force_sig(SIGSEGV, task); return 0; } -static int setup_sigframe(struct sigcontext *sc, struct pt_regs *regs) +static int setup_sigcontext(struct rt_sigframe __user *frame, + struct pt_regs *regs) { + struct sigcontext __user *sc = &frame->uc.uc_mcontext; int err = 0; - err |= copy_to_user(&sc->sc_pt_regs, regs, sizeof(struct pt_regs)); + err |= __copy_to_user(&sc->sc_pt_regs, regs, sizeof(struct pt_regs)); err |= save_fpu_state(sc); return err; } -static inline void * -get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size) +static inline void __user *get_sigframe(struct ksignal *ksig, + struct pt_regs *regs, size_t framesize) { - unsigned long usp; + unsigned long sp; + /* Default to using normal stack */ + sp = regs->usp; - /* Default to using normal stack. */ - usp = regs->usp; + /* + * If we are on the alternate signal stack and would overflow it, don't. + * Return an always-bogus address instead so we will die with SIGSEGV. + */ + if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) + return (void __user __force *)(-1UL); - /* This is the X/Open sanctioned signal stack switching. */ - if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(usp)) { - if (!on_sig_stack(usp)) - usp = current->sas_ss_sp + current->sas_ss_size; - } - return (void *)((usp - frame_size) & -8UL); + /* This is the X/Open sanctioned signal stack switching. */ + sp = sigsp(sp, ksig) - framesize; + + /* Align the stack frame. */ + sp &= -8UL; + + return (void __user *)sp; } static int @@ -140,208 +131,128 @@ setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) { struct rt_sigframe *frame; int err = 0; - struct csky_vdso *vdso = current->mm->context.vdso; - frame = get_sigframe(&ksig->ka, regs, sizeof(*frame)); - if (!frame) - return 1; + frame = get_sigframe(ksig, regs, sizeof(*frame)); + if (!access_ok(frame, sizeof(*frame))) + return -EFAULT; - err |= __put_user(ksig->sig, &frame->sig); - err |= __put_user(&frame->info, &frame->pinfo); - err |= __put_user(&frame->uc, &frame->puc); err |= copy_siginfo_to_user(&frame->info, &ksig->info); - /* Create the ucontext. */ + /* Create the ucontext. */ err |= __put_user(0, &frame->uc.uc_flags); - err |= __put_user(0, &frame->uc.uc_link); - err |= __put_user((void *)current->sas_ss_sp, - &frame->uc.uc_stack.ss_sp); - err |= __put_user(sas_ss_flags(regs->usp), - &frame->uc.uc_stack.ss_flags); - err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); - err |= setup_sigframe(&frame->uc.uc_mcontext, regs); - err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); - + err |= __put_user(NULL, &frame->uc.uc_link); + err |= __save_altstack(&frame->uc.uc_stack, regs->usp); + err |= setup_sigcontext(frame, regs); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); if (err) - goto give_sigsegv; + return -EFAULT; - /* Set up registers for signal handler */ - regs->usp = (unsigned long)frame; - regs->pc = (unsigned long)ksig->ka.sa.sa_handler; - regs->lr = (unsigned long)vdso->rt_signal_retcode; + /* Set up to return from userspace. */ + regs->lr = (unsigned long)(vdso->rt_signal_retcode); -adjust_stack: - regs->a0 = ksig->sig; /* first arg is signo */ - regs->a1 = (unsigned long)(&(frame->info)); - regs->a2 = (unsigned long)(&(frame->uc)); - return err; + /* + * Set up registers for signal handler. + * Registers that we don't modify keep the value they had from + * user-space at the time we took the signal. + * We always pass siginfo and mcontext, regardless of SA_SIGINFO, + * since some things rely on this (e.g. glibc's debug/segfault.c). + */ + regs->pc = (unsigned long)ksig->ka.sa.sa_handler; + regs->usp = (unsigned long)frame; + regs->a0 = ksig->sig; /* a0: signal number */ + regs->a1 = (unsigned long)(&(frame->info)); /* a1: siginfo pointer */ + regs->a2 = (unsigned long)(&(frame->uc)); /* a2: ucontext pointer */ -give_sigsegv: - if (ksig->sig == SIGSEGV) - ksig->ka.sa.sa_handler = SIG_DFL; - force_sig(SIGSEGV, current); - goto adjust_stack; + return 0; } -/* - * OK, we're invoking a handler - */ -static int -handle_signal(struct ksignal *ksig, struct pt_regs *regs) +static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) { - int ret; sigset_t *oldset = sigmask_to_save(); + int ret; - /* - * set up the stack frame, regardless of SA_SIGINFO, - * and pass info anyway. - */ - ret = setup_rt_frame(ksig, oldset, regs); + /* Are we from a system call? */ + if (in_syscall(regs)) { + /* Avoid additional syscall restarting via ret_from_exception */ + forget_syscall(regs); + + /* If so, check system call restarting.. */ + switch (regs->a0) { + case -ERESTART_RESTARTBLOCK: + case -ERESTARTNOHAND: + regs->a0 = -EINTR; + break; - if (ret != 0) { - force_sigsegv(ksig->sig, current); - return ret; + case -ERESTARTSYS: + if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { + regs->a0 = -EINTR; + break; + } + /* fallthrough */ + case -ERESTARTNOINTR: + regs->a0 = regs->orig_a0; + regs->pc -= TRAP0_SIZE; + break; + } } - /* Block the signal if we were successful. */ - spin_lock_irq(¤t->sighand->siglock); - sigorsets(¤t->blocked, ¤t->blocked, &ksig->ka.sa.sa_mask); - if (!(ksig->ka.sa.sa_flags & SA_NODEFER)) - sigaddset(¤t->blocked, ksig->sig); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); + /* Set up the stack frame */ + ret = setup_rt_frame(ksig, oldset, regs); - return 0; + signal_setup_done(ret, ksig, 0); } -/* - * Note that 'init' is a special process: it doesn't get signals it doesn't - * want to handle. Thus you cannot kill init even with a SIGKILL even by - * mistake. - * - * Note that we go through the signals twice: once to check the signals - * that the kernel can handle, and then we build all the user-level signal - * handling stack-frames in one go after that. - */ static void do_signal(struct pt_regs *regs) { - unsigned int retval = 0, continue_addr = 0, restart_addr = 0; struct ksignal ksig; - /* - * We want the common case to go fast, which - * is why we may in certain cases get here from - * kernel mode. Just return without doing anything - * if so. - */ - if (!user_mode(regs)) + if (get_signal(&ksig)) { + /* Actually deliver the signal */ + handle_signal(&ksig, regs); return; + } - /* - * If we were from a system call, check for system call restarting... - */ + /* Did we come from a system call? */ if (in_syscall(regs)) { + /* Avoid additional syscall restarting via ret_from_exception */ forget_syscall(regs); - continue_addr = regs->pc; -#if defined(__CSKYABIV2__) - restart_addr = continue_addr - 4; -#else - restart_addr = continue_addr - 2; -#endif - retval = regs->a0; - /* - * Prepare for system call restart. We do this here so that a - * debugger will see the already changed. - */ - switch (retval) { + /* Restart the system call - no handlers present */ + switch (regs->a0) { case -ERESTARTNOHAND: case -ERESTARTSYS: case -ERESTARTNOINTR: regs->a0 = regs->orig_a0; - regs->pc = restart_addr; + regs->pc -= TRAP0_SIZE; break; case -ERESTART_RESTARTBLOCK: - regs->a0 = -EINTR; + regs->a0 = regs->orig_a0; + regs_syscallid(regs) = __NR_restart_syscall; + regs->pc -= TRAP0_SIZE; break; } } - if (try_to_freeze()) - goto no_signal; - /* - * Get the signal to deliver. When running under ptrace, at this - * point the debugger may change all our registers ... + * If there is no signal to deliver, we just put the saved + * sigmask back. */ - if (get_signal(&ksig)) { - /* - * Depending on the signal settings we may need to revert the - * decision to restart the system call. But skip this if a - * debugger has chosen to restart at a different PC. - */ - if (regs->pc == restart_addr) { - if (retval == -ERESTARTNOHAND || - (retval == -ERESTARTSYS && - !(ksig.ka.sa.sa_flags & SA_RESTART))) { - regs->a0 = -EINTR; - regs->pc = continue_addr; - } - } - - /* Whee! Actually deliver the signal. */ - if (handle_signal(&ksig, regs) == 0) { - /* - * 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; - } - -no_signal: - if (in_syscall(regs)) { - forget_syscall(regs); - - /* - * Handle restarting a different system call. As above, - * if a debugger has chosen to restart at a different PC, - * ignore the restart. - */ - if (retval == -ERESTART_RESTARTBLOCK - && regs->pc == continue_addr) { -#if defined(__CSKYABIV2__) - regs->regs[3] = __NR_restart_syscall; - regs->pc -= 4; -#else - regs->regs[9] = __NR_restart_syscall; - regs->pc -= 2; -#endif - } - - /* - * 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); - } - } + restore_saved_sigmask(); } -asmlinkage void -do_notify_resume(unsigned int thread_flags, struct pt_regs *regs) +/* + * notification of userspace execution resumption + * - triggered by the _TIF_WORK_MASK flags + */ +asmlinkage void do_notify_resume(struct pt_regs *regs, + unsigned long thread_info_flags) { - if (thread_flags & _TIF_SIGPENDING) + /* Handle pending signal delivery */ + if (thread_info_flags & _TIF_SIGPENDING) do_signal(regs); - if (thread_flags & _TIF_NOTIFY_RESUME) { + if (thread_info_flags & _TIF_NOTIFY_RESUME) { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); } |