Improve spinlocks and add locking to pfa

src/arch/i386/interrupts/spinlock.asm

@@ -1,10 +1,10 @@
; Spinlock implementation

global spinlock_lock
global spinlock_unlock
global _spinlock_lock
global _spinlock_unlock

; Lock the spinlock
spinlock_lock:
_spinlock_lock:
    push eax
    push ebp

@@ -20,7 +20,7 @@ _spinlock_spin:
    ret

; Unlock the spinlock
spinlock_unlock:
_spinlock_unlock:
    push eax
    push ebx

src/include/kernel/spinlock.h

@@ -2,9 +2,12 @@
#define _SPINLOCK_H

#include <stdint.h>
typedef uint32_t* spinlock_t;
typedef uint32_t spinlock_t;

extern void spinlock_lock(spinlock_t lock);
extern void spinlock_unlock(spinlock_t lock);
extern void _spinlock_lock(spinlock_t* lock);
extern void _spinlock_unlock(spinlock_t* lock);

#define spinlock_lock(LOCK) _spinlock_lock(&(LOCK));
#define spinlock_unlock(LOCK) _spinlock_unlock(&(LOCK));

#endif

src/include/mem/frame.h

@@ -1,7 +1,6 @@
// Physical Frame Allocator
// Plan for allocator:
// Run length encoded linked list of free frames

#include <kernel/spinlock.h>
#include <stdbool.h>
#include <stdlib.h>
#include <stdint.h>
@@ -18,6 +17,7 @@ struct frame_node {
};

typedef struct {
    spinlock_t lock;
	uintptr_t base;
	frame_node_t* free_lists[MAX_FRAMES];
} frame_alloc_t;

src/kernel/mem/frame.c

@@ -2,6 +2,8 @@
#include <mem/kmalloc.h>
#include <mem/slab.h>

#include <kernel/spinlock.h>

#include <kprint.h>
#include <stdint.h>
#include <math.h>
@@ -101,6 +103,8 @@ void* frame_alloc(size_t want_count) {
        return NULL;
    }

    spinlock_lock(buddy_alloc.lock);

    // Find the smallest frame count with space
    for ( int count = want_count; count <= MAX_FRAMES; count++ ) {
        if ( buddy_alloc.free_lists[count - 1] != NULL ) {
@@ -117,11 +121,14 @@ void* frame_alloc(size_t want_count) {
                frame_add_free_item(chunk_end, return_count, false);
            }

            spinlock_unlock(buddy_alloc.lock);

            return (void*) address;
        }
    }

    spinlock_unlock(buddy_alloc.lock);

    // Didin't find anything :(
    return NULL;
}
@@ -130,7 +137,9 @@ void* frame_alloc(size_t want_count) {
//   address - starting address of the allocation
//   count   - amount of frames to return
void frame_dealloc(void* address, size_t count) {
    spinlock_lock(buddy_alloc.lock);
    frame_add_free_item((uintptr_t) address, count, false);
    spinlock_unlock(buddy_alloc.lock);
}

// Prints out the current status of the allocator