syscalls: syscall logging

kernel-src/Makefile

@@ -10,7 +10,7 @@ LDFLAGS=-ffreestanding -nostdlib -lgcc -Wl,-T,"$(ARCHDIR)/kernel.ld" -g
 PRINTFOPTS=-DPRINTF_DISABLE_SUPPORT_FLOAT
 # flanterm includes break if the headers are moved into the include dir in the tree
 FLANTERMINCDIR=$(shell pwd)/flanterm
-CFLAGS=-g -ffreestanding -mcmodel=kernel -O2 -mno-red-zone -mno-mmx -mno-sse -mno-sse2 -nostdlib -Wall -I "${INCDIR}" -I "$(ARCHINCDIR)" -I "$(FLANTERMINCDIR)" $(PRINTFOPTS)
+CFLAGS=-g -ffreestanding -mcmodel=kernel -O2 -mno-red-zone -mgeneral-regs-only -mno-mmx -mno-sse -mno-sse2 -nostdlib -Wall -I "${INCDIR}" -I "$(ARCHINCDIR)" -I "$(FLANTERMINCDIR)" $(PRINTFOPTS)
 ASFLAGS=-felf64
 
 astral:	$(OBJS)

kernel-src/arch/x86-64/syscall.asm

@@ -21,6 +21,7 @@ extern syscall_dup2
 extern syscall_dup3
 extern syscall_fcntl
 extern syscall_chdir
+extern syscall_pipe2
 syscalltab:
 dq syscall_print
 dq syscall_mmap
@@ -44,7 +45,8 @@ dq syscall_dup2
 dq syscall_dup3
 dq syscall_fcntl
 dq syscall_chdir
-syscallcount equ 22
+dq syscall_pipe2
+syscallcount equ 23
 section .text
 global arch_syscall_entry
 ; on entry:
@@ -110,6 +112,14 @@ arch_syscall_entry:
 	mov rcx, rdx
 	mov rdx, rsi
 	mov rsi, rdi
+
+	; call logging function
+
+	mov rdi, rax
+	extern arch_syscall_log
+	call arch_syscall_log ; compiled with __attribute__((no_caller_saved_registers)) 
+
+	; prepare context argument
 	mov rdi, rsp
 	add rdi, 8 ; context pointer is after r9 argument
 	sti
@@ -123,6 +133,15 @@ arch_syscall_entry:
 	call syscall_invalid
 	.return:
 	cli
+
+	; call return logging function
+
+	mov rdi, rax
+	mov rsi, rdx
+	extern arch_syscall_log_return
+	call arch_syscall_log_return ; compiled with __attribute__((no_caller_saved_registers)) 
+
+
 	; restore context
 	add rsp, 32 ; r9 argument, cr2, gs, and fs are not popped.
 	pop rbx

kernel-src/arch/x86-64/syscalllog.c

@@ -0,0 +1,80 @@
+#include <logging.h>
+#include <arch/e9.h>
+
+#define SYSCALL_COUNT 23
+#define LOGSTR(x) arch_e9_puts(x)
+
+static char *name[] = {
+	"print",
+	"mmap",
+	"openat",
+	"read",
+	"seek",
+	"close",
+	"archctl",
+	"write",
+	"getpid",
+	"fstat",
+	"fstatat",
+	"fork",
+	"execve",
+	"exit",
+	"waitpid",
+	"munmap",
+	"getdents",
+	"dup",
+	"dup2",
+	"dup3",
+	"fcntl",
+	"chdir",
+	"pipe2"
+};
+
+static char *args[] = {
+	"N/A", // print will not have its argument printed
+	"hint %p length %lu prot %d flags %d fd %d offset %ld", // mmap
+	"dirfd %d path %s flags %d mode %o", // openat
+	"fd %d buffer %p size %lu", // read
+	"fd %d offset %ld whence %d", // seek
+	"fd %d", // close
+	"func %d arg %p", // archctl
+	"fd %d buffer %p size %lu", // write
+	"N/A", // getpid
+	"fd %d ustat %p", // fstat
+	"dirfd %d path %s ustat %p flags %d", // fstatat
+	"N/A", // fork
+	"path %s uargv %p uenvp %p", // execve
+	"status %d", // exit
+	"pid %d statusp %p options %d", // waitpid
+	"addr %p length %lu", // munmap
+	"dirfd %d buffer %p readmax %lu", // getdents
+	"oldfd %d", // dup
+	"oldfd %d newfd %d", // dup2
+	"oldfd %d newfd %d flags %d", //dup3
+	"fd %d cmd %d arg %lu", // fcntl
+	"path %s", // chdir
+	"flags %d", // pipe2
+};
+
+__attribute__((no_caller_saved_registers)) void arch_syscall_log(int syscall, uint64_t a1, uint64_t a2, uint64_t a3, uint64_t a4, uint64_t a5, uint64_t a6) {
+	char argbuff[768];
+	char printbuff[1024];
+
+	thread_t *thread = _cpu()->thread;
+	proc_t *proc = thread->proc;
+
+	snprintf(argbuff, 768, syscall < SYSCALL_COUNT ? args[syscall] : "N/A", a1, a2, a3, a4, a5, a6);
+	snprintf(printbuff, 1024, "\e[92msyscall: pid %d tid %d: %s: %s\n\e[0m", proc->pid, thread->tid, syscall < SYSCALL_COUNT ? name[syscall] : "invalid syscall", argbuff);
+
+	LOGSTR(printbuff);
+}
+
+__attribute__((no_caller_saved_registers)) void arch_syscall_log_return(int syscall, uint64_t ret, uint64_t errno) {
+	char printbuff[1024];
+
+	thread_t *thread = _cpu()->thread;
+	proc_t *proc = thread->proc;
+
+	snprintf(printbuff, 1024, "\e[94msyscall return: pid %d tid %d: %lu %lu\n\e[0m", proc->pid, thread->tid, ret, errno);
+	LOGSTR(printbuff);
+}