Add a test module

Makefile

@@ -20,7 +20,9 @@ STAGE_BIN=$(STAGE)/init \
 		  $(STAGE)/bin/mount \
 		  $(STAGE)/bin/umount \
 		  $(STAGE)/bin/date \
-		  $(STAGE)/bin/login
+		  $(STAGE)/bin/login \
+		  $(STAGE)/bin/insmod \
+		  $(STAGE)/test.ko
 
 # TODO
 # newlib: gettimeofday is broken?
@@ -98,6 +100,18 @@ $(STAGE)/bin/vsh: $(vsh_OBJS)
 $(STAGE)/bin/ase: $(ase_OBJS)
 	$(CC) -o $@ $(usr_LDFLAGS) $(ase_OBJS)
 
+$(STAGE)/test.ko: module.c module.ld
+	$(CC) \
+		-I ../kernel/include \
+		-r \
+		-O0 \
+		-g \
+		-mcmodel=large \
+		-Tmodule.ld \
+		-nostdlib \
+		-ffreestanding \
+		-o $@ module.c
+
 $(O)/vsh/%.o: vsh/%.c $(shell find vsh -name "*.h")
 	$(CC) -c -o $@ $(usr_CFLAGS) $<
 $(O)/vsh/%.o: vsh/%.S

core/bin/insmod.c

@@ -0,0 +1,63 @@
+#include <ygg/syscall.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+
+static __attribute__((optimize("-O0"))) int ygg_module_load(const char *file, const char *args) {
+    register uintptr_t rdi asm("rdi") = (uintptr_t) file;
+    register uintptr_t rsi asm("rsi") = (uintptr_t) args;
+    register uintptr_t rax asm("rax") = SYSCALL_NRX_MODULE_LOAD;
+    asm volatile ("syscall":::"rax","rdi","rsi");
+    (void) rdi;
+    (void) rsi;
+    return (int) rax;
+}
+
+static __attribute__((optimize("-O0"))) int ygg_module_unload(const char *name) {
+    register uintptr_t rdi asm("rdi") = (uintptr_t) name;
+    register uintptr_t rax asm("rax") = SYSCALL_NRX_MODULE_UNLOAD;
+    asm volatile ("syscall":::"rax","rdi");
+    (void) rdi;
+    return (int) rax;
+}
+
+static const char *usage = "Usage: insmod <module path>\n"
+                           "  OR   insmod -r <module name>\n";
+
+int main(int argc, char **argv) {
+    int res;
+
+    if (argc > 3 || argc < 2) {
+        fprintf(stderr, usage);
+        return -1;
+    }
+
+    if (getuid() != 0) {
+        fprintf(stderr, "Only root can do that\n");
+        return -1;
+    }
+
+    if (argc == 2) {
+        if (access(argv[1], F_OK) != 0) {
+            perror(argv[1]);
+            return -1;
+        }
+
+        if ((res = ygg_module_load(argv[1], NULL)) < 0) {
+            fprintf(stderr, "%s: %s\n", argv[1], strerror(-res));
+            return -1;
+        }
+    } else {
+        if (strcmp(argv[1], "-r")) {
+            fprintf(stderr, usage);
+            return -1;
+        }
+
+        if ((res = ygg_module_unload(argv[2])) < 0) {
+            fprintf(stderr, "%s: %s\n", argv[2], strerror(-res));
+            return -1;
+        }
+    }
+
+    return 0;
+}

module.c

@@ -0,0 +1,16 @@
+#include <ygg/module.h>
+#include <sys/debug.h>
+#include <stdint.h>
+
+MODULE_DESC("test-mod", 0x00010000);
+
+extern uint64_t system_time;
+
+void MODULE_EXIT(void) {
+    kinfo("Exiting the module!\n");
+}
+
+int MODULE_ENTRY(void) {
+    kinfo("This should work, I guess: %s, %d\n", "a string", 123);
+    return 0;
+}

module.ld

@@ -0,0 +1,27 @@
+ENTRY(_mod_entry);
+
+SECTIONS {
+    /*
+     * Modules are linked with 0x0 base virtual address
+     * and are position independent
+     */
+    . = 0x100000000;
+
+    .text : ALIGN(4K) {
+        *(.text*)
+    }
+
+    .rodata : {
+        *(.rodata)
+        *(.eh_frame)
+    }
+
+    .data : ALIGN(4K) {
+        *(.data*)
+    }
+
+    .bss : {
+        *(COMMON)
+        *(.bss*)
+    }
+}