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#include <kmalloc.h>
#include <slab_alloc.h>
#include <mutex.h>
#include <frame.h>
#include <paging.h>
#include <region.h>
#include <freemem.h>
static void* page_alloc_fun_for_kmalloc(size_t bytes) {
void* addr = region_alloc(bytes, "Core kernel heap", pf_handler_unexpected);
if (addr == 0) return 0;
// Map physical memory
for (void* i = addr; i < addr + bytes; i += PAGE_SIZE) {
int f = frame_alloc(1);
if (f == 0) goto failure;
if (!pd_map_page(i, f, true)) goto failure;
}
return addr;
failure:
for (void* i = addr; i < addr + bytes; i += PAGE_SIZE) {
int f = pd_get_frame(i);
if (f != 0) {
pd_unmap_page(i);
frame_free(f, 1);
}
}
return 0;
}
static slab_type_t slab_sizes[] = {
{ "8B kmalloc objects", 8, 2 },
{ "16B kmalloc objects", 16, 2 },
{ "32B kmalloc objects", 32, 2 },
{ "64B kmalloc objects", 64, 4 },
{ "128B kmalloc objects", 128, 4 },
{ "256B kmalloc objects", 256, 4 },
{ "512B kmalloc objects", 512, 8 },
{ "1KB kmalloc objects", 1024, 8 },
{ "2KB kmalloc objects", 2048, 16 },
{ "4KB kmalloc objects", 4096, 16 },
{ 0, 0, 0 }
};
static mem_allocator_t *kernel_allocator = 0;
STATIC_MUTEX(malloc_mutex);
void kmalloc_setup() {
kernel_allocator =
create_slab_allocator(slab_sizes, page_alloc_fun_for_kmalloc,
region_free_unmap_free);
}
static void* malloc0(size_t sz) {
void* res = 0;
mutex_lock(&malloc_mutex);
res = slab_alloc(kernel_allocator, sz);
mutex_unlock(&malloc_mutex);
return res;
}
void* malloc(size_t sz) {
void* res;
int tries = 0;
while ((res = malloc0(sz)) == 0 && (tries++) < 3) {
free_some_memory();
}
return res;
}
void free(void* ptr) {
mutex_lock(&malloc_mutex);
slab_free(kernel_allocator, ptr);
mutex_unlock(&malloc_mutex);
}
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