rework signal handling

JIRA: RTOS-539

hal/armv7a/_interrupts.S

@@ -277,7 +277,7 @@ _syscalls_dispatch:
 
 	blx syscalls_dispatch
 
-	cpsid if
+	/* Interrupts disabled by dispatcher */
 
 	str r0, [sp, #272]
 

hal/armv7a/cpu.c

@@ -90,28 +90,50 @@ int hal_cpuCreateContext(cpu_context_t **nctx, void *start, void *kstack, size_t
 }
 
 
-int hal_cpuPushSignal(void *kstack, void (*handler)(void), int n)
+int hal_cpuPushSignal(void *kstack, void (*handler)(void), cpu_context_t *signalCtx, int n)
 {
 	cpu_context_t *ctx = (void *)((char *)kstack - sizeof(cpu_context_t));
 
-	/* No signal handling inside IT block */
-	if (ctx->psr & 0x600fc00)
-		return -1;
+	hal_memcpy(signalCtx, ctx, sizeof(cpu_context_t));
 
-	PUTONSTACK(ctx->sp, u32, ctx->pc | !!(ctx->psr & THUMB_STATE));
-	PUTONSTACK(ctx->sp, int, n);
+	signalCtx->pc = (u32)handler & ~1;
+	signalCtx->sp -= sizeof(cpu_context_t);
 
-	ctx->pc = (u32)handler & ~1;
+	if (((u32)handler & 2) != 0) {
+		signalCtx->psr |= THUMB_STATE;
+	}
+	else {
+		signalCtx->psr &= ~THUMB_STATE;
+	}
 
-	if ((u32)handler & 1)
-		ctx->psr |= THUMB_STATE;
-	else
-		ctx->psr &= ~THUMB_STATE;
+	PUTONSTACK(signalCtx->sp, u32, ctx->sp);
+	PUTONSTACK(signalCtx->sp, u32, ctx->pc);
+	PUTONSTACK(signalCtx->sp, cpu_context_t *, signalCtx);
+	PUTONSTACK(signalCtx->sp, int, n);
 
 	return 0;
 }
 
 
+void hal_cpuSigreturn(void *ustack, cpu_context_t *ctx)
+{
+	u32 pc, sp;
+
+	GETFROMSTACK(ustack, u32, pc, 2);
+	GETFROMSTACK(ustack, u32, sp, 3);
+
+	ctx->pc = pc;
+	ctx->sp = sp;
+
+	if ((pc & 2) != 0) {
+		ctx->psr |= THUMB_STATE;
+	}
+	else {
+		ctx->psr &= ~THUMB_STATE;
+	}
+}
+
+
 char *hal_cpuInfo(char *info)
 {
 	size_t n = 0;

hal/armv7a/spinlock.c

@@ -111,6 +111,12 @@ void hal_spinlockDestroy(spinlock_t *spinlock)
 }
 
 
+void hal_spinlockCtxIrqClr(spinlock_ctx_t *sc)
+{
+	*sc |= NO_INT;
+}
+
+
 __attribute__ ((section (".init"))) void _hal_spinlockInit(void)
 {
 	spinlocks.first = NULL;

hal/armv7m/arch/cpu.h

@@ -261,9 +261,14 @@ static inline int hal_cpuSupervisorMode(cpu_context_t *ctx)
 }
 
 
-static inline int hal_cpuPushSignal(void *kstack, void (*handler)(void), int sig)
+static inline int hal_cpuPushSignal(void *kstack, void (*handler)(void), cpu_context_t *signalCtx, int sig)
+{
+	return -1;
+}
+
+
+static inline void hal_cpuSigreturn(void *ustack, cpu_context_t *ctx)
 {
-	return 0;
 }
 
 

hal/armv7m/spinlock.c

@@ -112,6 +112,12 @@ void hal_spinlockDestroy(spinlock_t *spinlock)
 }
 
 
+void hal_spinlockCtxIrqClr(spinlock_ctx_t *sc)
+{
+	*sc = 1;
+}
+
+
 __attribute__ ((section (".init"))) void _hal_spinlockInit(void)
 {
 	spinlocks.first = NULL;

hal/cpu.h

@@ -94,7 +94,10 @@ extern void *hal_cpuGetUserSP(cpu_context_t *ctx);
 extern int hal_cpuSupervisorMode(cpu_context_t *ctx);
 
 
-extern int hal_cpuPushSignal(void *kstack, void (*handler)(void), int n);
+extern int hal_cpuPushSignal(void *kstack, void (*handler)(void), cpu_context_t *signalCtx, int n);
+
+
+extern void hal_cpuSigreturn(void *ustack, cpu_context_t *ctx);
 
 
 extern void hal_longjmp(cpu_context_t *ctx);

hal/ia32/_interrupts.S

@@ -177,7 +177,7 @@ _interrupts_syscall:
 	pushl %eax
 	sti
 	call syscalls_dispatch
-	cli
+	/* Interrupts disabled by dispatcher */
 	addl $8, %esp
 	movl %eax, (4 * CTXPUSHL - EAX_OFFSET)(%esp)	/* Save return value to eax in context */
 	jmp interrupts_popContext

hal/ia32/cpu.c

@@ -152,21 +152,36 @@ void _hal_cpuSetKernelStack(void *kstack)
 }
 
 
-int hal_cpuPushSignal(void *kstack, void (*handler)(void), int n)
+int hal_cpuPushSignal(void *kstack, void (*handler)(void), cpu_context_t *signalCtx, int n)
 {
 	cpu_context_t *ctx = (void *)((char *)kstack - sizeof(cpu_context_t));
-	char *ustack = (char *)ctx->esp;
 
-	PUTONSTACK(ustack, u32, ctx->eip);
-	PUTONSTACK(ustack, int, n);
+	hal_memcpy(signalCtx, ctx, sizeof(cpu_context_t));
 
-	ctx->eip = (u32)handler;
-	ctx->esp = (u32)ustack;
+	signalCtx->eip = (u32)handler;
+	signalCtx->esp -= sizeof(cpu_context_t);
+
+	PUTONSTACK(signalCtx->esp, u32, ctx->esp);
+	PUTONSTACK(signalCtx->esp, u32, ctx->eip);
+	PUTONSTACK(signalCtx->esp, cpu_context_t *, signalCtx);
+	PUTONSTACK(signalCtx->esp, int, n);
 
 	return 0;
 }
 
 
+void hal_cpuSigreturn(void *ustack, cpu_context_t *ctx)
+{
+	u32 eip, esp;
+
+	GETFROMSTACK(ustack, u32, eip, 2);
+	GETFROMSTACK(ustack, u32, esp, 3);
+
+	ctx->eip = eip;
+	ctx->esp = esp;
+}
+
+
 void hal_longjmp(cpu_context_t *ctx)
 {
 	/* clang-format off */

hal/ia32/spinlock.c

@@ -125,6 +125,12 @@ void hal_spinlockDestroy(spinlock_t *spinlock)
 }
 
 
+void hal_spinlockCtxIrqClr(spinlock_ctx_t *sc)
+{
+	*sc &= ~0x200;
+}
+
+
 __attribute__ ((section (".init"))) void _hal_spinlockInit(void)
 {
 	spinlocks.first = NULL;

hal/riscv64/_interrupts.S

@@ -160,17 +160,18 @@
 
 	ld tp, 280(sp)       /* tp */
 
-	addi sp, sp, 296
-
 	/* Restore task's stack pointer */
-	ld sp, -8(sp)
+	ld sp, 288(sp)
 .endm
 
 
 .global interrupts_handleintexc
 .type interrupts_handleintexc, @function
 interrupts_handleintexc:
 .align 8
+	/* Disable interrupts */
+	csrc sstatus, SR_SIE
+
 	SAVE
 	mv a0, sp
 
@@ -207,8 +208,8 @@ interrupts_handleintexc:
 
 	csrs sstatus, SR_SIE
 	call syscalls_dispatch
+	/* Interrupts disabled by dispatcher */
 	sd a0, 56(sp)
-	csrc sstatus, SR_SIE
 	j 5f
 4:
 	beq a0, zero, 5f

hal/riscv64/arch/cpu.h

@@ -208,23 +208,6 @@ static inline int hal_cpuSupervisorMode(cpu_context_t *ctx)
 }
 
 
-static inline int hal_cpuPushSignal(void *kstack, void (*handler)(void), int n)
-{
-#if 0
-	cpu_context_t *ctx = (void *)((char *)kstack - sizeof(cpu_context_t));
-	char *ustack = (char *)ctx->esp;
-
-	PUTONSTACK(ustack, u32, ctx->eip);
-	PUTONSTACK(ustack, int, n);
-
-	ctx->eip = (u32)handler;
-	ctx->esp = (u32)ustack;
-#endif
-
-	return 0;
-}
-
-
 /* Code used in disabled code vm/object.c - map_pageFault */
 #if 0
 static inline void *hal_cpuGetFaultAddr(void)

hal/riscv64/cpu.c

@@ -24,9 +24,6 @@
 #include "arch/types.h"
 
 
-extern int threads_schedule(unsigned int n, cpu_context_t *context, void *arg);
-
-
 int hal_platformctl(void *ptr)
 {
 	return EOK;
@@ -38,7 +35,7 @@ int hal_platformctl(void *ptr)
 /* TODO: use clz/ctz instructions */
 unsigned int hal_cpuGetLastBit(unsigned long v)
 {
-	int lb = 63;
+	unsigned int lb = 63;
 
 	if (!(v & 0xffffffff00000000L)) {
 		lb -= 32;
@@ -74,7 +71,7 @@ unsigned int hal_cpuGetLastBit(unsigned long v)
 
 unsigned int hal_cpuGetFirstBit(unsigned long v)
 {
-	int fb = 0;
+	unsigned int fb = 0;
 
 	if (!(v & 0xffffffffL)) {
 		fb += 32;
@@ -116,17 +113,19 @@ int hal_cpuCreateContext(cpu_context_t **nctx, void *start, void *kstack, size_t
 	cpu_context_t *ctx;
 
 	*nctx = NULL;
-	if (kstack == NULL)
+	if (kstack == NULL) {
 		return -EINVAL;
+	}
 
-	if (kstacksz < sizeof(cpu_context_t))
+	if (kstacksz < sizeof(cpu_context_t)) {
 		return -EINVAL;
+	}
 
-	ctx = (cpu_context_t *)(kstack + kstacksz - 2 * sizeof(cpu_context_t));
+	ctx = (cpu_context_t *)((char *)kstack + kstacksz - sizeof(cpu_context_t));
 
-	__asm__ __volatile__ (
-		"sd gp, %0"
-		: "=m" (ctx->gp));
+	/* clang-format off */
+	__asm__ volatile("sd gp, %0" : "=m"(ctx->gp));
+	/* clang-format on */
 
 	ctx->pc = (u64)start;
 	ctx->sp = (u64)ctx;
@@ -186,6 +185,37 @@ int hal_cpuCreateContext(cpu_context_t **nctx, void *start, void *kstack, size_t
 }
 
 
+int hal_cpuPushSignal(void *kstack, void (*handler)(void), cpu_context_t *signalCtx, int n)
+{
+	cpu_context_t *ctx = (void *)((char *)kstack - sizeof(cpu_context_t));
+
+	hal_memcpy(signalCtx, ctx, sizeof(cpu_context_t));
+
+	signalCtx->sepc = (u64)handler;
+	signalCtx->sp -= sizeof(cpu_context_t);
+
+	PUTONSTACK(signalCtx->sp, u64, ctx->sp);
+	PUTONSTACK(signalCtx->sp, u64, ctx->sepc);
+	PUTONSTACK(signalCtx->sp, cpu_context_t *, signalCtx);
+	/* Signal number */
+	PUTONSTACK(signalCtx->sp, int, n);
+
+	return 0;
+}
+
+
+void hal_cpuSigreturn(void *ustack, cpu_context_t *ctx)
+{
+	u64 sepc, sp;
+
+	GETFROMSTACK(ustack, u64, sepc, 2);
+	GETFROMSTACK(ustack, u64, sp, 3);
+
+	ctx->sepc = sepc;
+	ctx->sp = sp;
+}
+
+
 void _hal_cpuSetKernelStack(void *kstack)
 {
 	csr_write(sscratch, kstack);
@@ -228,7 +258,6 @@ char *hal_cpuFeatures(char *features, unsigned int len)
 	char *compatible, *isa, *mmu;
 	u32 clock;
 
-
 	while (!dtb_getCPU(n++, &compatible, &clock, &isa, &mmu)) {
 
 		l = hal_strlen(compatible);

hal/riscv64/spinlock.c

@@ -124,6 +124,12 @@ void hal_spinlockDestroy(spinlock_t *spinlock)
 }
 
 
+void hal_spinlockCtxIrqClr(spinlock_ctx_t *sc)
+{
+	*sc &= ~SR_SIE;
+}
+
+
 __attribute__ ((section (".init"))) void _hal_spinlockInit(void)
 {
 	spinlocks.first = NULL;

hal/sparcv8leon3/arch/cpu.h

@@ -224,6 +224,11 @@ static inline void hal_cpuRestore(cpu_context_t *curr, cpu_context_t *next)
 }
 
 
+static inline void hal_cpuSigreturn(void *ustack, cpu_context_t *ctx)
+{
+}
+
+
 /* core management */
 
 

hal/sparcv8leon3/cpu.c

@@ -134,9 +134,9 @@ void _hal_cpuSetKernelStack(void *kstack)
 }
 
 
-int hal_cpuPushSignal(void *kstack, void (*handler)(void), int n)
+int hal_cpuPushSignal(void *kstack, void (*handler)(void), cpu_context_t *signalCtx, int n)
 {
-	return 0;
+	return -1;
 }
 
 

hal/sparcv8leon3/hal.c

@@ -26,6 +26,12 @@ unsigned int relOffs;
 extern void _hal_cpuInit(void);
 
 
+void hal_sigreturn(void *ustack, cpu_context_t *ctx)
+{
+	return;
+}
+
+
 void *hal_syspageRelocate(void *data)
 {
 	return data;