mirror of
https://git.stationery.faith/corn/corn.git
synced 2024-11-22 00:22:17 +00:00
memory works
This commit is contained in:
parent
175e5b55b8
commit
e71a141533
GPG key ID:
744AB800E383AE52
10 changed files with 132 additions and 96 deletions
2
Makefile
2
Makefile
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@ -47,4 +47,4 @@ $(BUILD_DIR)/$(ISO_NAME): $(BUILD_DIR)/$(K_BIN_NAME) grub.cfg
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grub-mkrescue -o $(BUILD_DIR)/$(ISO_NAME) $(BUILD_DIR)/iso
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run: all
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qemu-system-x86_64 $(BUILD_DIR)/$(ISO_NAME) -serial stdio
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qemu-system-x86_64 $(BUILD_DIR)/$(ISO_NAME) -serial stdio -m 4G
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@ -1,9 +1,10 @@
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global start
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global pml4_list
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global init_pdpt
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global init_pd
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global init_pt
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global kernel_pml4
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global kernel_pdpt_0
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global kernel_pd_0
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global kernel_pt_0
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global paging_pt
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global bootstrap_pt
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extern kmain
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extern amd64_shim
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bits 32
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@ -25,15 +26,17 @@ mb_end:
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section .bss
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align 4096
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pml4_list: ; reserve memory for initial 512 pml4 entires
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kernel_pml4: ; reserve memory for initial 512 pml4 entires
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resb 4096
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init_pdpt: ; reserve memory for initial 512 pdpt entires
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kernel_pdpt_0: ; reserve memory for initial 512 pdpt entires
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resb 4096
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init_pd: ; reserve memory for initial 512 pd entries
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kernel_pd_0: ; reserve memory for initial 512 pd entries
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resb 4096
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init_pt: ; reserve memory for initial 512 pt entries
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kernel_pt_0: ; reserve memory for initial 512 pt entries
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resb 4096
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paging_pt: ; reserve memory for 512 paging reserved pt entires
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paging_pt: ; reserve pages for pager mappings
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resb 4096
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bootstrap_pt: ; reserve pages to bootstrap pager
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resb 4096
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align 16
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@ -85,6 +88,7 @@ start:
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mov esp, stack_end
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mov ebp, stack_end
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push DWORD 0
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push ebx
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mov edi, 0x1000
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@ -93,13 +97,13 @@ start:
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mov ecx, 4096
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rep stosd
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mov edi, cr3
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; FIXME: Update boot.S to point base of paging to pml4e_list, see above
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mov DWORD [edi], 0x2003 ; Set the uint32_t at the destination index to 0x2003.
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add edi, 0x1000 ; Add 0x1000 to the destination index.
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mov DWORD [edi], 0x3003 ; Set the uint32_t at the destination index to 0x3003.
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add edi, 0x1000 ; Add 0x1000 to the destination index.
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mov DWORD [edi], 0x4003 ; Set the uint32_t at the destination index to 0x4003.
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add edi, 0x1000 ; Add 0x1000 to the destination index.
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mov DWORD [edi], kernel_pdpt_0 + 3 ; Set the uint32_t at the destination index to 0x2003.
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mov edi, kernel_pdpt_0 ; Add 0x1000 to the destination index.
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mov DWORD [edi], kernel_pd_0 + 3 ; Set the uint32_t at the destination index to 0x3003.
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mov edi, kernel_pd_0 ; Add 0x1000 to the destination index.
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mov DWORD [edi], kernel_pt_0 + 3 ; Set the uint32_t at the destination index to 0x4003.
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mov edi, kernel_pt_0 ; Add 0x1000 to the destination index.
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mov ebx, 0x00000003 ; Set the B-register to 0x00000003.
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mov ecx, 512 ; Set the C-register to 512.
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@ -132,6 +136,7 @@ start:
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bits 64
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code64:
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pop rdi
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call amd64_shim
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mov rdi, rax
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call kmain
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@ -1,24 +1,28 @@
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#include "mboot.h"
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#include "serial.h"
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#include <stddef.h>
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#include <lib.h>
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static void read_cmdline(struct mboot_info *info, struct mboot_tag *tag, char *data, uint8_t len) {
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static void read_cmdline(struct mboot_tag *tag, char *data, uint8_t len) {
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if (len >= CMDLINE_MAX)
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len = CMDLINE_MAX; // truncate :(
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memcpy(tag->data.cmdline, data, len);
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tag->data.cmdline[len] = '\0';
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info->tags[MBOOT_CMDLINE] = *tag;
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}
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static void read_xsdp(struct mboot_info *info, struct mboot_tag *tag, char *data) {
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static void read_memorymap(struct mboot_tag *tag, uint64_t size, uint32_t *data) {
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tag->data.memory_map = (struct memory_map *) data;
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tag->data.memory_map->size = size;
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}
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static void read_xsdp(struct mboot_tag *tag, char *data) {
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tag->data.rootsdp = (void *) data;
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info->tags[MBOOT_XSDP] = *tag;
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}
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static uint32_t *read_tag(struct mboot_info *info, uint32_t *data) {
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struct mboot_tag tag;
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tag.type = ((uint16_t*)data)[0];
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tag.type = *((uint16_t *)data);
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tag.size = data[1];
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tag.valid = 1;
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@ -26,15 +30,20 @@ static uint32_t *read_tag(struct mboot_info *info, uint32_t *data) {
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switch (tag.type) {
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case MBOOT_CMDLINE:
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read_cmdline(info, &tag, (char *)(data + 2), data_len);
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read_cmdline(&tag, (char *)(data + 2), data_len);
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break;
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case MBOOT_MEMORYMAP:
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read_memorymap(&tag, tag.size, data + 2);
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break;
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case MBOOT_XSDP:
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read_xsdp(info, &tag, (char *) (data + 2));
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read_xsdp(&tag, (char *) (data + 2));
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break;
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default:
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break;
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}
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info->tags[tag.type] = tag;
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if(tag.size % 8 != 0) {
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tag.size += 8 - (tag.size % 8);
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}
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@ -42,12 +51,13 @@ static uint32_t *read_tag(struct mboot_info *info, uint32_t *data) {
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return data + tag.size / sizeof(uint32_t);
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}
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struct mboot_info mboot_load_info(void *mboot_info) {
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struct mboot_info mboot_load_info(const void *mboot_info) {
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struct mboot_info info = {0};
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uint32_t* data = (uint32_t*) mboot_info;
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info.total_size = *data++;
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info.reserved = *data++;
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while((uint8_t*) data < (uint8_t*) mboot_info + info.total_size) {
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data = read_tag(&info, data);
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@ -25,14 +25,14 @@ enum mboot_tag_type {
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struct mboot_info {
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uint32_t total_size;
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uint32_t reserved;
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struct mboot_tag tags[21];
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struct mboot_tag tags[22];
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};
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/**
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* Loads the multi boot information
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* @param mboot_info - the pointer passed from multiboot2
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*/
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struct mboot_info mboot_load_info(void *mboot_info);
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struct mboot_info mboot_load_info(const void *mboot_info);
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/**
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* Gets a tag from multiboot
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@ -7,18 +7,9 @@
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#include <memory/physalloc.h>
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#include <memory/virtalloc.h>
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#include "paging.h"
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#include "bindings.h"
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#define F_PRESENT 0x001
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#define F_WRITEABLE 0x002
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#define F_UNPRIVILEGED 0x004
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#define F_WRITETHROUGH 0x008
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#define F_CACHEDISABLE 0x010
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#define F_ACCESSED 0x020
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#define F_DIRTY 0x040
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#define F_MEGABYTE 0x080
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#define F_GLOBAL 0x100
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// PAGE MAP LEVEL 4 ENTRY
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struct pml4e {
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uint64_t flags : 6;
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@ -61,19 +52,19 @@ struct pte {
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};
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// bss segment, can write to
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extern struct pml4e pml4_list[512];
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extern struct pdpte init_pdpt[512];
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extern struct pde init_pd[512];
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extern struct pte init_pt[512];
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extern struct pml4e kernel_pml4[512];
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extern struct pdpte kernel_pdpt_0[512];
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extern struct pde kernel_pd_0[512];
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extern struct pte bootstrap_pt[512];
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extern struct pte paging_pt[512]; // paging_pt should NEVER be outside of this file, NEVER i say
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// paged address to read page tables
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// the structures are not gurenteed to be ident mapped
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// map them here with map_<type>(phys_addr) before useing structures
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static struct pdpte *pdpt_mapped = (void *) (uintptr_t) 0x1000;
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static struct pdpte *pd_mapped = (void *) (uintptr_t) 0x2000;
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static struct pdpte *pt_mapped = (void *) (uintptr_t) 0x3000;
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void *addr_mapped = (void *) (uintptr_t) 0x4000;
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static struct pdpte *pdpt_mapped = (void *) (uintptr_t) 0x201000;
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static struct pdpte *pd_mapped = (void *) (uintptr_t) 0x202000;
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static struct pdpte *pt_mapped = (void *) (uintptr_t) 0x203000;
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void *addr_mapped = (void *) (uintptr_t) 0x204000;
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static inline void invlpg(void *addr) {
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__asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
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@ -172,6 +163,7 @@ int map_page(struct pml4e *pml4, void *virt_addr, void *phys_addr, unsigned int
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map_pt(__pt);
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pt_mapped[pt_offset].flags = F_PRESENT | flags;
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pt_mapped[pt_offset].address = (((uint64_t)phys_addr) >> 12);
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invlpg(virt_addr);
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return 0;
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}
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@ -236,51 +228,52 @@ done:
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}
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void paging_init(void) {
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memset(pml4_list, 0, 4096);
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pml4_list[0].flags = F_PRESENT | F_WRITEABLE;
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pml4_list[0].address = (uint64_t)init_pdpt >> 12;
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kernel_pml4[0].flags = F_PRESENT | F_WRITEABLE;
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kernel_pml4[0].address = (uint64_t)(&kernel_pdpt_0) >> 12;
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kernel_pdpt_0[0].flags = F_PRESENT | F_WRITEABLE;
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kernel_pdpt_0[0].address = (uint64_t)(&kernel_pd_0) >> 12;
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kernel_pd_0[1].flags = F_PRESENT | F_WRITEABLE;
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kernel_pd_0[1].address = (uint64_t)(&paging_pt) >> 12;
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kernel_pd_0[2].flags = F_PRESENT | F_WRITEABLE;
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kernel_pd_0[2].address = (uint64_t)(&bootstrap_pt) >> 12;
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memset(init_pdpt, 0, 4096);
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init_pdpt[0].flags = F_PRESENT | F_WRITEABLE;
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init_pdpt[0].address = (uint64_t)init_pd >> 12;
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memset(pml4_list, 0, 4096);
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init_pd[0].flags = F_PRESENT | F_WRITEABLE;
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init_pd[0].address = (uint64_t)paging_pt >> 12;
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init_pd[1].flags = F_PRESENT | F_WRITEABLE;
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init_pd[1].address = (uint64_t)init_pt >> 12;
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memset(init_pt, 0, 4096);
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memset(paging_pt, 0, 4096);
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memset(&paging_pt, 0, 4096);
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memset(&bootstrap_pt, 0, 4096);
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}
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static inline void *page_align(void *addr) {
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uintptr_t a = (uintptr_t) addr;
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a += PAGE_SIZE + 1;
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a += PAGE_SIZE - 1;
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a /= PAGE_SIZE;
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a *= PAGE_SIZE;
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return (void *) a;
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}
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void *mmap(void *addr, size_t len) {
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len += (uintptr_t)addr % PAGE_SIZE;
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int pages = (len + PAGE_SIZE - 1) / PAGE_SIZE;
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len += (long)addr % PAGE_SIZE;
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long pages = (len + PAGE_SIZE - 1) / PAGE_SIZE;
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void *virt = virtaddr_alloc(pages);
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if (virt == NULL)
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if (virt == NULL) {
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return NULL;
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}
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void *phys = page_align(addr);
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for (long i = 0; i < pages; i++) {
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void *virt_temp = (char *)virt + (i * PAGE_SIZE);
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void *phys_temp = (char *)phys + (i * PAGE_SIZE);
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map_page(pml4_list, virt_temp, phys_temp, F_WRITEABLE);
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map_page(kernel_pml4, virt_temp, phys_temp, F_WRITEABLE);
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}
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return addr;
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map_page(kernel_pml4, virt, (void*)0x23443, F_WRITEABLE);
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return virt;
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}
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void unmap(void *addr) {
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long pages = virtaddr_free(addr);
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for (long i = 0; i < pages; i++) {
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void *virt = (char *)addr + (i * PAGE_SIZE);
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unmap_page(pml4_list, virt);
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unmap_page(kernel_pml4, virt);
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}
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}
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@ -296,7 +289,7 @@ void *alloc_pages(int count) {
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for (int i = 0; i < count; i++) {
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void *virt_temp = (char *)virt + (i * PAGE_SIZE);
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void *phys_temp = (char *)phys + (i * PAGE_SIZE);
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map_page(pml4_list, virt_temp, phys_temp, F_WRITEABLE);
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map_page(kernel_pml4, virt_temp, phys_temp, F_WRITEABLE);
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}
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return virt;
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}
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@ -307,7 +300,7 @@ void free_page(void *virt) {
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return;
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for (long i = 0; i < pages; i++) {
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void *virt_temp = (char *)virt + (i * PAGE_SIZE);
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unmap_page(pml4_list, virt_temp);
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unmap_page(kernel_pml4, virt_temp);
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}
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}
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@ -318,3 +311,11 @@ void memory_lock(void) {
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void memory_unlock(void) {
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sti();
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}
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int kmap_page(void *virt_addr, void *phys_addr, unsigned int flags) {
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return map_page(kernel_pml4, virt_addr, phys_addr, flags);
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}
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int kunmap_page(void *virt_addr) {
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return unmap_page(kernel_pml4, virt_addr);
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}
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16
src/arch/amd64/paging.h
Normal file
16
src/arch/amd64/paging.h
Normal file
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@ -0,0 +1,16 @@
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#pragma once
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#define F_PRESENT 0x001
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#define F_WRITEABLE 0x002
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#define F_UNPRIVILEGED 0x004
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#define F_WRITETHROUGH 0x008
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#define F_CACHEDISABLE 0x010
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#define F_ACCESSED 0x020
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#define F_DIRTY 0x040
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#define F_MEGABYTE 0x080
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#define F_GLOBAL 0x100
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int kmap_page(void *virt_addr, void *phys_addr, unsigned int flags);
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int kunmap_page(void *virt_addr);
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void paging_init(void);
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@ -4,23 +4,17 @@
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#include <shim.h>
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#include <memory.h>
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#include "paging.h"
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#include "mboot.h"
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static struct boot_info boot_info;
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// entry point for amd64
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void* amd64_shim(void *mboot_data_ptr) {
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//struct pml4e *pml4 = (struct pml4e *)0x1000;
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//struct pdpte *pdpt = (struct pdpte *)0x2000;
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//struct pde *pd = (struct pde *)0x3000;
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//struct pte *pt = (struct pte *)0x4000;
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//pd[1].flags = F_PRESENT | F_WRITEABLE;
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//pd[1].address = ((uint64_t)pt) >> 12;
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//map_page(pml4, (void *)0x80000000, (void *)0xB8002, F_WRITEABLE);
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//__asm("invlpg 0x200000");
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//void *ret;
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//find_phys_addr(pml4, (void *)0x80000000, &ret);
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//return ret;
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serial_init();
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paging_init();
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kmap_page(mboot_data_ptr, mboot_data_ptr, F_WRITEABLE);
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struct mboot_info mboot_info;
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mboot_info = mboot_load_info(mboot_data_ptr);
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@ -10,6 +10,7 @@ void kmain(struct boot_info *info) {
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memory_init(info->map);
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//*(char*)(0xB8002 + 0x20'0000) = 'd';
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itoa((long)info, buf, 16);
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itoa(*(long*)info, buf, 16);
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//fb_init(1024, 768);
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serial_out_str(buf);
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}
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@ -7,8 +7,9 @@
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#include <memory/physalloc.h>
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#include <memory/virtalloc.h>
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extern uintptr_t kernel_start;
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extern uintptr_t kernel_end;
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extern char kernel_start;
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extern char kernel_end;
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#define kaddr(addr) ((uintptr_t)(&addr))
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// between memory_start and kernel_start will be the bitmap
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static uintptr_t memory_start = 0;
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@ -113,9 +114,9 @@ void free_phys_pages(void *ptr, int pages) {
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static bool segment_invalid(const struct memory_segment *segment) {
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if (segment->type != 1) return false;
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if (segment->addr < kernel_start) return false;
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if (segment->addr < kaddr(kernel_start)) return false;
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if (segment->addr + segment->len < memory_start) return false;
|
||||
if (segment->addr + segment->len < kernel_start) return false;
|
||||
if (segment->addr + segment->len < kaddr(kernel_start)) return false;
|
||||
return true;
|
||||
}
|
||||
|
||||
|
|
@ -127,7 +128,7 @@ static struct memory_area segment_to_area(const struct memory_segment *segment)
|
|||
if (memory_start)
|
||||
start = memory_start;
|
||||
else
|
||||
start = kernel_end;
|
||||
start = kaddr(kernel_end);
|
||||
|
||||
if (segment->addr < start) {
|
||||
addr = start;
|
||||
|
|
@ -144,7 +145,7 @@ static struct memory_area segment_to_area(const struct memory_segment *segment)
|
|||
}
|
||||
|
||||
static uintptr_t page_align(uintptr_t ptr) {
|
||||
return ptr + PAGE_SIZE - 1 / PAGE_SIZE;
|
||||
return (ptr + PAGE_SIZE - 1) / PAGE_SIZE * PAGE_SIZE;
|
||||
}
|
||||
|
||||
void memory_init(struct memory_map *map) {
|
||||
|
|
@ -165,7 +166,7 @@ void memory_init(struct memory_map *map) {
|
|||
|
||||
struct memory_segment *segment = &map->entries[0];
|
||||
int segment_count = 0;
|
||||
|
||||
|
||||
for(; (uintptr_t) segment < end; segment++) {
|
||||
if (segment_invalid(segment))
|
||||
continue;
|
||||
|
|
@ -180,15 +181,17 @@ void memory_init(struct memory_map *map) {
|
|||
|
||||
//HACK: terrible hack bad bad bad bad
|
||||
long bitmap_size = bitmap_pages * PAGE_SIZE;
|
||||
bitmap = (uint64_t *) page_at(page_count - bitmap_pages);
|
||||
bitmap = (uint64_t *) page_align(kaddr(kernel_end));
|
||||
char buf[20];
|
||||
|
||||
long page_area_size = segment_count * sizeof(struct memory_area);
|
||||
char *page_area_addr = (char *)bitmap + bitmap_size;
|
||||
|
||||
bitmap = mmap(bitmap, bitmap_size);
|
||||
ltoa((long)bitmap, buf, 16);
|
||||
memset(bitmap, 0, 12);
|
||||
memset(bitmap, 0, bitmap_size);
|
||||
|
||||
memory_start = page_align(kernel_end + bitmap_size + page_area_size);
|
||||
memory_start = page_align(kaddr(kernel_end) + bitmap_size + page_area_size);
|
||||
|
||||
page_area_addr = mmap(page_area_addr, page_area_size);
|
||||
page_start = (struct memory_area *) page_area_addr;
|
||||
|
|
|
|||
|
|
@ -26,7 +26,7 @@ static struct addr_node *alloc_node(void) {
|
|||
} else {
|
||||
struct addr_node *node = &nodes[bss_nodes];
|
||||
bss_nodes += 1;
|
||||
node->is_bss = false;
|
||||
node->is_bss = true;
|
||||
return node;
|
||||
}
|
||||
return NULL;
|
||||
|
|
@ -39,8 +39,8 @@ static void free_node(struct addr_node *node) {
|
|||
|
||||
void virtaddr_init(void) {
|
||||
struct addr_node init = {
|
||||
.start = 0,
|
||||
.end = UINT64_MAX,
|
||||
.start = 0x400000, // third page table
|
||||
.end = 0x1000000000000, // 48bit memory address max
|
||||
.next = NULL,
|
||||
.prev = NULL,
|
||||
.is_alloc = false,
|
||||
|
|
@ -53,6 +53,10 @@ void virtaddr_init(void) {
|
|||
|
||||
void *virtaddr_alloc(int n_pages) {
|
||||
|
||||
|
||||
if (n_pages < 1)
|
||||
return NULL;
|
||||
|
||||
long n_length = n_pages * PAGE_SIZE;
|
||||
struct addr_node *node = start_node;
|
||||
|
||||
|
|
@ -64,17 +68,19 @@ void *virtaddr_alloc(int n_pages) {
|
|||
long length = node->end - node->start;
|
||||
if (length >= n_length) {
|
||||
struct addr_node *new = alloc_node();
|
||||
if (node == NULL)
|
||||
if (node == NULL) {
|
||||
return NULL;
|
||||
new->next = node;
|
||||
node->prev = new;
|
||||
}
|
||||
if (node->prev != NULL) {
|
||||
node->prev->next = new;
|
||||
}
|
||||
new->next = node;
|
||||
node->prev = new;
|
||||
new->start = node->start;
|
||||
new->end = new->start + n_length;
|
||||
node->start = new->end;
|
||||
new->is_alloc = true;
|
||||
new->next = node;
|
||||
return (void *) new->start;
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue