save/restore context from rsp

6 files changed, 102 insertions, 37 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 86c4893..741e158 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -42,6 +42,7 @@ OBJS = \
 	src/scheduler/ap_startup.o \
 	src/scheduler/atomic.o \
 	src/scheduler/scheduler.o \
+	src/scheduler/switch.o \
 	src/sys/syscall_asm.o \
 	src/sys/syscall.o \
 	src/sys/userspace_asm.o \
diff --git a/kernel/include/regs.h b/kernel/include/regs.h
index 81b8a69..ec2ed89 100644
--- a/kernel/include/regs.h
+++ b/kernel/include/regs.h
@@ -1,6 +1,8 @@
 #ifndef REGS_H
 #define REGS_H
 
+#include <types.h>
+
 #define R15_OFF 0x0
 #define R14_OFF 0x08
 #define R13_OFF 0x10
@@ -24,4 +26,30 @@
 #define RSP_OFF 0x100
 #define SS_OFF 0x108
 
+struct regs_t {
+	uint64_t r15;
+	uint64_t r14;
+	uint64_t r13;
+	uint64_t r12;
+	uint64_t rbp;
+	uint64_t rbx;
+	uint64_t seg;
+	uint64_t r11;
+	uint64_t r10;
+	uint64_t r9;
+	uint64_t r8;
+	uint64_t rdi;
+	uint64_t rsi;
+	uint64_t rdx;
+	uint64_t rcx;
+	uint64_t rax;
+	uint64_t error;
+	uint64_t rip;
+	uint64_t cs;
+	uint64_t rflags;
+	uint64_t rsp;
+	uint64_t ss;
+} __attribute__((packed));
+typedef struct regs_t regs_t;
+
 #endif
diff --git a/kernel/include/x86_64_regs.S b/kernel/include/x86_64_regs.S
index 4b20539..644f4f8 100644
--- a/kernel/include/x86_64_regs.S
+++ b/kernel/include/x86_64_regs.S
@@ -8,6 +8,22 @@
  * else use push/pop_callee_saved with push/pop_caller_saved
  */
 
+.set R15_OFF, 0x0
+.set R14_OFF, 0x08
+.set R13_OFF, 0x10
+.set R12_OFF, 0x18
+.set RBP_OFF, 0x20
+.set RBX_OFF, 0x28
+.set SEG_OFF, 0x30
+.set R11_OFF, 0x38
+.set R10_OFF, 0x40
+.set R9_OFF, 0x48
+.set R8_OFF, 0x50
+.set RDI_OFF, 0x58
+.set RSI_OFF, 0x60
+.set RDX_OFF, 0x68
+.set RCX_OFF, 0x70
+.set RAX_OFF, 0x78
 .set ERROR_OFF, 0x80
 .set RIP_OFF, 0x88
 .set CS_OFF, 0x90
diff --git a/kernel/src/check/panic.c b/kernel/src/check/panic.c
index ac40078..b5e02a2 100644
--- a/kernel/src/check/panic.c
+++ b/kernel/src/check/panic.c
@@ -15,33 +15,33 @@ __attribute__((noreturn)) void panic(uint64_t rsp, const char *s, ...)
 	va_end(list);
 
 	if (rsp) {
-		uint64_t seg = *(uint64_t *)(rsp + SEG_OFF);
+		regs_t *regs = (regs_t *)rsp;
 
 		printf("info regs:\n");
-		printf("rax: 0x%x; ", *(uint64_t *)(rsp + RAX_OFF));
-		printf("rbx: 0x%x; ", *(uint64_t *)(rsp + RBX_OFF));
-		printf("rcx: 0x%x; ", *(uint64_t *)(rsp + RCX_OFF));
-		printf("rdx: 0x%x; ", *(uint64_t *)(rsp + RDX_OFF));
-		printf("rdi: 0x%x; ", *(uint64_t *)(rsp + RDI_OFF));
-		printf("rsi: 0x%x; ", *(uint64_t *)(rsp + RSI_OFF));
-		printf("rsp: 0x%x; ", *(uint64_t *)(rsp + RSP_OFF));
-		printf("rbp: 0x%x; ", *(uint64_t *)(rsp + RBP_OFF));
-		printf("r8: 0x%x; ", *(uint64_t *)(rsp + R8_OFF));
-		printf("r9: 0x%x; ", *(uint64_t *)(rsp + R9_OFF));
-		printf("r10: 0x%x; ", *(uint64_t *)(rsp + R10_OFF));
-		printf("r11: 0x%x; ", *(uint64_t *)(rsp + R11_OFF));
-		printf("r12: 0x%x; ", *(uint64_t *)(rsp + R12_OFF));
-		printf("r13: 0x%x; ", *(uint64_t *)(rsp + R13_OFF));
-		printf("r14: 0x%x; ", *(uint64_t *)(rsp + R14_OFF));
-		printf("r15: 0x%x; ", *(uint64_t *)(rsp + R15_OFF));
-		printf("rip: 0x%x; ", *(uint64_t *)(rsp + RIP_OFF));
-		printf("cs: 0x%x; ", *(uint64_t *)(rsp + CS_OFF));
-		printf("ds: 0x%x; ", seg >> 48);
-		printf("ss: 0x%x; ", *(uint64_t *)(rsp + SS_OFF));
-		printf("es: 0x%x; ", (seg >> 32) & 0xFFFF);
-		printf("fs: 0x%x; ", (seg >> 16) & 0xFFFF);
-		printf("gs: 0x%x; ", seg & 0xFFFF);
-		printf("rflags: 0x%x; ", *(uint64_t *)(rsp + RFLAGS_OFF));
+		printf("rax: 0x%x; ", regs->rax);
+		printf("rbx: 0x%x; ", regs->rbx);
+		printf("rcx: 0x%x; ", regs->rcx);
+		printf("rdx: 0x%x; ", regs->rdx);
+		printf("rdi: 0x%x; ", regs->rdi);
+		printf("rsi: 0x%x; ", regs->rsi);
+		printf("rsp: 0x%x; ", regs->rsp);
+		printf("rbp: 0x%x; ", regs->rbp);
+		printf("r8: 0x%x; ", regs->r8);
+		printf("r9: 0x%x; ", regs->r9);
+		printf("r10: 0x%x; ", regs->r10);
+		printf("r11: 0x%x; ", regs->r11);
+		printf("r12: 0x%x; ", regs->r12);
+		printf("r13: 0x%x; ", regs->r13);
+		printf("r14: 0x%x; ", regs->r14);
+		printf("r15: 0x%x; ", regs->r15);
+		printf("rip: 0x%x; ", regs->rip);
+		printf("cs: 0x%x; ", regs->cs);
+		printf("ds: 0x%x; ", regs->seg >> 48);
+		printf("ss: 0x%x; ", regs->ss);
+		printf("es: 0x%x; ", (regs->seg >> 32) & 0xFFFF);
+		printf("fs: 0x%x; ", (regs->seg >> 16) & 0xFFFF);
+		printf("gs: 0x%x; ", regs->seg & 0xFFFF);
+		printf("rflags: 0x%x; ", regs->rflags);
 	}
 
 	disable_interrupts();
diff --git a/kernel/src/scheduler/process.c b/kernel/src/scheduler/process.c
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/kernel/src/scheduler/process.c
diff --git a/kernel/src/scheduler/switch.S b/kernel/src/scheduler/switch.S
index f4d0e79..4e216e0 100644
--- a/kernel/src/scheduler/switch.S
+++ b/kernel/src/scheduler/switch.S
@@ -1,18 +1,38 @@
 #include "x86_64_regs.S"
 
-.global context_switch
-context_switch:
-	/* switch rsp to old task's %rsp */
+/* %rdi - irq's rsp */
+/* %rsi - task's rsp */
+.global save_to_rsp
+save_context_to_rsp:
+	mov %rsi, %rsp
+	push SS_OFF(%rdi)
+	push RSP_OFF(%rdi)
+	push RFLAGS_OFF(%rdi)
+	push CS_OFF(%rdi)
+	push RIP_OFF(%rdi)
+	push $0
+	push RAX_OFF(%rdi)
+	push RCX_OFF(%rdi)
+	push RDX_OFF(%rdi)
+	push RSI_OFF(%rdi)
+	push RDI_OFF(%rdi)
+	push R8_OFF(%rdi)
+	push R9_OFF(%rdi)
+	push R10_OFF(%rdi)
+	push R11_OFF(%rdi)
+	push SEG_OFF(%rdi)
+	push RBX_OFF(%rdi)
+	push RBP_OFF(%rdi)
+	push R12_OFF(%rdi)
+	push R13_OFF(%rdi)
+	push R14_OFF(%rdi)
+	push R15_OFF(%rdi)
 
-	/* save all old task's registers */
-	push_caller_saved
-	push_callee_saved
-
-	/* save old task's rsp & rip */
-	call schedule
-	/* get new task's rsp & rip */
-
-	/* restore all new task's registers */
+/* %rdi - task's rsp */
+.global restore_from_rsp
+restore_context_from_rsp:
+	mov %rdi, %rsp
 	pop_callee_saved
 	pop_caller_saved
+	add $8, %rsp
 	iretq