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added bitmap initialization based on Multiboot infos

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This commit is contained in:
Steffen Vogel 2014-06-30 00:10:04 +02:00
parent b55887a95d
commit 92c90c299a
3 changed files with 120 additions and 6 deletions
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7
arch/x86/include/asm/multiboot.h
View file

@ -41,6 +41,13 @@
#include <eduos/stddef.h>
/// Does the bootloader provide mem_* fields?
#define MULTIBOOT_INFO_MEM (1 << 0)
/// Does the bootloader provide a list of modules?
#define MULTIBOOT_INFO_MODS (1 << 3)
/// Does the bootloader provide a full memory map?
#define MULTIBOOT_INFO_MEM_MAP (1 << 6)
typedef uint16_t multiboot_uint16_t;
typedef uint32_t multiboot_uint32_t;
typedef uint64_t multiboot_uint64_t;

24
kernel/main.c
View file

@ -33,10 +33,14 @@
#include <eduos/processor.h>
#include <eduos/tasks.h>
#include <eduos/syscall.h>
#include <eduos/memory.h>
#include <asm/irq.h>
#include <asm/irqflags.h>
#include <asm/atomic.h>
#include <asm/page.h>
/*
/*
* Note that linker symbols are not variables, they have no memory allocated for
* maintaining a value, rather their address is their value.
*/
@ -47,6 +51,11 @@ extern const void bss_end;
extern char __BUILD_DATE;
extern char __BUILD_TIME;
/* Page frame counters */
atomic_int32_t total_pages;
atomic_int32_t total_allocated_pages;
atomic_int32_t total_available_pages;
static void userfoo(void* arg)
{
char str[256];
@ -91,6 +100,7 @@ static int eduos_init(void)
// initialize .bss section
memset((void*)&bss_start, 0x00, ((size_t) &bss_end - (size_t) &bss_start));
memory_init();
system_init();
irq_init();
timer_init();
@ -104,16 +114,18 @@ int main(void)
{
tid_t id1;
tid_t id2;
eduos_init();
kprintf("This is eduOS %s Build %u, %u\n", EDUOS_VERSION, &__BUILD_DATE, &__BUILD_TIME);
kprintf("Kernel starts at %p and ends at %p\n", &kernel_start, &kernel_end);
irq_enable();
system_calibration();
kprintf("This is eduOS %s Build %u, %u\n", EDUOS_VERSION, &__BUILD_DATE, &__BUILD_TIME);
kprintf("Kernel starts at %p and ends at %p\n", &kernel_start, &kernel_end);
kprintf("Processor frequency: %u MHz\n", get_cpu_frequency());
kprintf("Total memory: %lu KiB\n", atomic_int32_read(&total_pages) * PAGE_SIZE / 1024);
kprintf("Total memory available: %lu KiB\n", atomic_int32_read(&total_available_pages) * PAGE_SIZE / 1024);
create_kernel_task(&id1, foo, "foo1", NORMAL_PRIO);
create_kernel_task(&id2, wrapper, "userfoo", NORMAL_PRIO);

95
mm/memory.c
View file

@ -27,12 +27,20 @@
#include <eduos/stddef.h>
#include <eduos/stdlib.h>
#include <eduos/stdio.h>
#include <eduos/string.h>
#include <eduos/spinlock.h>
#include <asm/atomic.h>
#include <asm/multiboot.h>
#include <asm/page.h>
/*
* Note that linker symbols are not variables, they have no memory allocated for
* maintaining a value, rather their address is their value.
*/
extern const void kernel_start;
extern const void kernel_end;
static char stack[MAX_TASKS-1][KERNEL_STACK_SIZE];
static char bitmap[BITMAP_SIZE];
@ -142,3 +150,90 @@ int put_pages(size_t phyaddr, size_t npages)
return ret;
}
int memory_init(void)
{
unsigned int i;
size_t addr;
int ret = 0;
// mark all memory as used
memset(bitmap, 0xff, BITMAP_SIZE);
if (mb_info) {
if (mb_info->flags & MULTIBOOT_INFO_MEM_MAP) {
multiboot_memory_map_t* mmap = (multiboot_memory_map_t*) ((size_t) mb_info->mmap_addr);
multiboot_memory_map_t* mmap_end = (void*) ((size_t) mb_info->mmap_addr + mb_info->mmap_length);
// mark available memory as free
while (mmap < mmap_end) {
if (mmap->type == MULTIBOOT_MEMORY_AVAILABLE) {
for (addr=mmap->addr; addr < mmap->addr + mmap->len; addr += PAGE_SIZE) {
page_clear_mark(addr >> PAGE_BITS);
atomic_int32_inc(&total_pages);
atomic_int32_inc(&total_available_pages);
}
}
mmap++;
}
}
else if (mb_info->flags & MULTIBOOT_INFO_MEM) {
size_t page;
size_t pages_lower = mb_info->mem_lower >> 2;
size_t pages_upper = mb_info->mem_upper >> 2;
for (page=0; page<pages_lower; page++)
page_clear_mark(page);
for (page=0; page<pages_upper; page++)
page_clear_mark(page + (1<<8)); /* 1 MiB offset */
atomic_int32_add(&total_pages, pages_lower + pages_upper);
atomic_int32_add(&total_available_pages, pages_lower + pages_upper);
}
else {
kputs("Unable to initialize the memory management subsystem\n");
while (1) HALT;
}
// mark mb_info as used
page_set_mark((size_t) mb_info >> PAGE_BITS);
atomic_int32_inc(&total_allocated_pages);
atomic_int32_dec(&total_available_pages);
if (mb_info->flags & MULTIBOOT_INFO_MODS) {
// mark modules list as used
for(addr=mb_info->mods_addr; addr<mb_info->mods_addr+mb_info->mods_count*sizeof(multiboot_module_t); addr+=PAGE_SIZE) {
page_set_mark(addr >> PAGE_BITS);
atomic_int32_inc(&total_allocated_pages);
atomic_int32_dec(&total_available_pages);
}
// mark modules as used
multiboot_module_t* mmodule = (multiboot_module_t*) ((size_t) mb_info->mods_addr);
for(i=0; i<mb_info->mods_count; i++) {
for(addr=mmodule[i].mod_start; addr<mmodule[i].mod_end; addr+=PAGE_SIZE) {
page_set_mark(addr >> PAGE_BITS);
atomic_int32_inc(&total_allocated_pages);
atomic_int32_dec(&total_available_pages);
}
}
}
}
// mark kernel as used
for(addr=(size_t) &kernel_start; addr<(size_t) &kernel_end; addr+=PAGE_SIZE) {
page_set_mark(addr >> PAGE_BITS);
atomic_int32_inc(&total_allocated_pages);
atomic_int32_dec(&total_available_pages);
}
// enable paging and map SMP, VGA, Multiboot modules etc.
/*ret = page_init();
if (BUILTIN_EXPECT(ret, 0))
return ret;
*/
return ret;
}