Accept tasks as a parameter on initrd extraction

This allows this functionality to be properly extracted for unit tests.

Signed-off-by: Miquel Sabaté Solà <mikisabate@gmail.com>

4 files changed, 21 insertions, 13 deletions

diff --git a/include/fbos/init.h b/include/fbos/init.h
index 711d2cf..f0f1dce 100644
--- a/include/fbos/init.h
+++ b/include/fbos/init.h
@@ -2,6 +2,7 @@
 #define __FBOS_INIT_H
 
 #include <fbos/compiler.h>
+#include <fbos/sched.h>
 
 // Tracks the amount of seconds that have elapsed since activating timer
 // interrupts.
@@ -11,7 +12,8 @@ extern uint64_t seconds_elapsed;
 
 // Extract the executables from the initrd that is located at `base_addr` and
 // has the given `size`.
-void extract_initrd(const unsigned char *const base_addr, uint64_t size);
+void extract_initrd(const unsigned char *const base_addr, uint64_t size,
+					struct task_struct tasks[4]);
 
 // Setup the interrupt vectors and the SBI timer.
 void setup_interrupts(void);
diff --git a/kernel/initrd.c b/kernel/initrd.c
index 3fc2a52..d503dd8 100644
--- a/kernel/initrd.c
+++ b/kernel/initrd.c
@@ -69,7 +69,7 @@ __kernel int get_task_id_from_path(const char *const path)
 // Fetch the 'entry_addr' for the ELF binary pointed by 'addr'. If everything
 // goes right, the task identified by 'task_id' will finally be initialized with
 // said address.
-__kernel void get_task_entry_addr(int task_id, const unsigned char *const addr)
+__kernel const void *get_task_entry_addr(const unsigned char *const addr)
 {
 	uint64_t offset;
 
@@ -84,10 +84,11 @@ __kernel void get_task_entry_addr(int task_id, const unsigned char *const addr)
 	}
 
 	offset = (uint64_t)addr[0x18];
-	tasks[task_id].entry_addr = (const void *)(addr + offset);
+	return (const void *)(addr + offset);
 }
 
-__kernel void extract_initrd(const unsigned char *const initrd_addr, uint64_t size)
+__kernel void extract_initrd(const unsigned char *const initrd_addr, uint64_t size,
+							 struct task_struct g_tasks[4])
 {
 	char buffer[BUFFER_SIZE];
 	uint64_t name_size, file_size, padding, base = 0;
@@ -140,8 +141,10 @@ __kernel void extract_initrd(const unsigned char *const initrd_addr, uint64_t si
 		// there might be some padding in between the header and the file.
 		padding = 4 - ((CPIO_HEADER_SIZE + name_size) & 3);
 
-		// And extract everything from the ELF file for the given task.
-		get_task_entry_addr(task_id, &initrd_addr[base + name_size + CPIO_HEADER_SIZE + padding]);
+		// And extract the entry address for the current task from the ELF
+		// binary.
+		g_tasks[task_id].entry_addr =
+			get_task_entry_addr(&initrd_addr[base + name_size + CPIO_HEADER_SIZE + padding]);
 
 		// Advance the base to the next file.
 		base += CPIO_HEADER_SIZE + name_size + padding + file_size;
diff --git a/kernel/main.c b/kernel/main.c
index 58d67f5..fdcef1f 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -4,13 +4,16 @@
 #include <fbos/sched.h>
 #include <fbos/dt.h>
 
-unsigned long init_stack[4][THREAD_SIZE / sizeof(unsigned long)];
+// Stacks to be used by our processes.
+unsigned long stack[4][THREAD_SIZE / sizeof(unsigned long)];
 
+// Initialize the list of structs by providing a fixed stack address and empty
+// values everywhere else.
 struct task_struct tasks[4] = {
-	[TASK_INIT] = { .stack = init_stack[0], .entry_addr = nullptr, },
-	[TASK_FIZZ] = { .stack = init_stack[1], .entry_addr = nullptr, },
-	[TASK_BUZZ] = { .stack = init_stack[2], .entry_addr = nullptr, },
-	[TASK_FIZZBUZZ] = { .stack = init_stack[3], .entry_addr = nullptr, },
+	[TASK_INIT] = { .stack = stack[0], .entry_addr = nullptr, },
+	[TASK_FIZZ] = { .stack = stack[1], .entry_addr = nullptr, },
+	[TASK_BUZZ] = { .stack = stack[2], .entry_addr = nullptr, },
+	[TASK_FIZZBUZZ] = { .stack = stack[3], .entry_addr = nullptr, },
 };
 
 /*
@@ -24,7 +27,7 @@ __noreturn __kernel void start_kernel(void *dtb)
 
 	// Extract information from the DTB blob.
 	struct initrd_addr addr = find_dt_initrd_addr(dtb);
-	extract_initrd((unsigned char *)addr.start, addr.end - addr.start);
+	extract_initrd((unsigned char *)addr.start, addr.end - addr.start, tasks);
 
 	// At this point everything has already been handled: setup the interrupt
 	// vector and enable the timer to start ticking and scheduling the three
diff --git a/test/test_initrd.c b/test/test_initrd.c
index 73429b8..2d0d045 100644
--- a/test/test_initrd.c
+++ b/test/test_initrd.c
@@ -30,7 +30,7 @@ int main(void)
 
 	contents[fsize] = 0;
 
-	extract_initrd(contents, (uint64_t)fsize);
+	extract_initrd(contents, (uint64_t)fsize, tasks);
 	free(contents);
 
 	// TODO