context struct for ISRs rather than using param registers; second-stage handlers should deal with that i think

3 files changed, 79 insertions, 29 deletions

diff --git a/kc/core/cpu/exceptions.S b/kc/core/cpu/exceptions.S
index 087cf12..8aa109e 100644
--- a/kc/core/cpu/exceptions.S
+++ b/kc/core/cpu/exceptions.S
@@ -1,32 +1,26 @@
 #include "exceptions.h"
 #include "interrupt.h"
 
-.macro EXCEPTION_BEGIN vec:req, code=0
+.macro EXCEPTION_BEGIN vec:req, code
     // just in case something tried to be clever before
-    cld
+    pushq $\vec
+    .ifb \code
+    pushq $0
+    .endif
     // push param registers
     ISR_STORE_PARAM_REGS
-    // store certain parameters
-    movb $\vec,%dil
-    .if \code
-    movq ISR_PARAM_REGS_SIZE(%rsp), %rsi
-    .else
-    xor %rsi, %rsi
-    .endif
     // caller-saved registers
     ISR_STORE_CALLER_REGS
     // callee-saved registers
     ISR_STORE_CALLEE_REGS
 .endm
 
-.macro EXCEPTION_END vec:req, code=0
+.macro EXCEPTION_END vec:req, code
     // restore all the registers
     ISR_RESTORE_CALLEE_REGS
     ISR_RESTORE_CALLER_REGS
     ISR_RESTORE_PARAM_REGS
-    .if \code
-    add $8, %rsp
-    .endif
+    add $16, %rsp
     iretq
 .endm
 
@@ -37,6 +31,7 @@
     .else
     EXCEPTION_BEGIN \vec
     .endif
+    movq %rsp, %rdi
     ISR_CALL \name\()_handler
     .if \vec > 9 && \vec < 15 || \vec == 17 || \vec == 21 || \vec > 28 && \vec < 31
     EXCEPTION_END \vec, 1
diff --git a/kc/core/cpu/exceptions.h b/kc/core/cpu/exceptions.h
index c35c8ca..a43ba23 100644
--- a/kc/core/cpu/exceptions.h
+++ b/kc/core/cpu/exceptions.h
@@ -21,10 +21,70 @@
 
 #ifndef __ASSEMBLER__
 
-void general_protection_isr();
-void general_protection_handler();
-void page_fault_isr();
-void page_fault_handler();
+#include "kprint.h"
+
+struct isr_context_param_regs
+{
+    uint64_t r9, r8, rcx, rdx, rsi, rdi;
+};
+
+struct isr_context_caller_regs
+{
+    uint64_t r11, r10, rax;
+};
+
+struct isr_context_callee_regs
+{
+    uint64_t r15, r14, r13, r12, rbp, rbx;
+};
+
+struct isr_context_entry_state
+{
+    uint64_t vector, code, rip, cs, rflags;
+};
+
+struct isr_context
+{
+    struct isr_context_callee_regs callee_regs;
+    struct isr_context_caller_regs caller_regs;
+    struct isr_context_param_regs param_regs;
+    struct isr_context_entry_state entry_state;
+};
+
+static inline void print_exception_context(struct isr_context *context)
+{
+    kprintf(
+            "exception %#hhx:%x context:\n"
+            "interrupt entry state:\n"
+            "rip: %#hx:%p rflags: %#x\n"
+            "parameter registers:\n" 
+            "rdi: %#lx rsi: %#lx rdx: %lx\n"
+            "rcx: %#lx r8: %#lx r9: %#lx\n"
+            "caller registers:\n"
+            "rax: %#lx r10: %#lx r11: %#lx\n"
+            "callee registers:\n"
+            "rbx: %#lx rbp: %#lx r12: %lx\n"
+            "r13: %#lx r14: %#lx r15: %#lx\n",
+            context->entry_state.vector, context->entry_state.code,
+            context->entry_state.cs, context->entry_state.rip,
+            context->entry_state.rflags,
+
+            context->param_regs.rdi, context->param_regs.rsi,
+            context->param_regs.rdx, context->param_regs.rcx,
+            context->param_regs.r8,context->param_regs.r9,
+
+            context->caller_regs.rax, context->caller_regs.r10,
+            context->caller_regs.r11,
+
+            context->callee_regs.rbx, context->callee_regs.rbp,
+            context->callee_regs.r12, context->callee_regs.r13, 
+            context->callee_regs.r14, context->callee_regs.r15);
+}
+
+void general_protection_isr(void);
+void general_protection_handler(struct isr_context *context);
+void page_fault_isr(void);
+void page_fault_handler(struct isr_context *context);
 
 void exceptions_init(void);
 
diff --git a/kc/core/memory/memory.c b/kc/core/memory/memory.c
index 1a33629..0fbc941 100644
--- a/kc/core/memory/memory.c
+++ b/kc/core/memory/memory.c
@@ -15,6 +15,7 @@
 #include "panic.h"
 #include "vm_object.h"
 #include "cpu/mmu.h"
+#include "cpu/exceptions.h"
 
 #include <stdint.h>
 
@@ -589,10 +590,8 @@ int anonymous_page_handler(
     return 0;
 }
 
-int page_fault_handler(uint8_t vector, uint32_t code)
+void page_fault_handler(struct isr_context *context)
 {
-    (void)vector;
-
     void *address;
     __asm__ volatile ("movq %%cr2, %0" : "=r"(address));
 
@@ -601,28 +600,24 @@ int page_fault_handler(uint8_t vector, uint32_t code)
 
     if (!node)
     {
-        kprintf("error: page fault in unmanaged address %#lx\n",
-                address);
+        print_exception_context(context);
+        kprintf("error: page fault in unmanaged address %#lx\n", address);
         PANIC(UNHANDLED_FAULT);
     }
 
     if (!node->object->handler)
     {
+        print_exception_context(context);
         kprintf("error: vm object at %p has no fault handler\n");
         PANIC(UNHANDLED_FAULT);
     }
-
-    return node->object->handler(node, code, address);
 }
 
-int general_protection_handler(uint8_t vector, uint32_t code)
+void general_protection_handler(struct isr_context *context)
 {
     //TODO: implement #gp handler
-    (void)vector;
-    (void)code;
-
     kputs("general protection violation\n");
+    print_exception_context(context);
     PANIC(UNHANDLED_FAULT);
-    return 0;
 }