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-rw-r--r--arch/x86_64/paging.c257
1 files changed, 0 insertions, 257 deletions
diff --git a/arch/x86_64/paging.c b/arch/x86_64/paging.c
deleted file mode 100644
index dc27ca2..0000000
--- a/arch/x86_64/paging.c
+++ /dev/null
@@ -1,257 +0,0 @@
-#include "paging.h"
-#include "interrupt.h"
-#include "io/log.h"
-#include "lib/jove.h"
-#include "lib/string.h"
-#include "lib/hashtable.h"
-#include "mem/memory.h"
-#include "boot/boot.h"
-
-extern void *_kernel_end;
-
-PAGEALIGN static uint64_t s_kernel_initial_pml4[512];
-PAGEALIGN static uint64_t s_kernel_initial_pml3[2][512];
-PAGEALIGN static uint64_t s_kernel_initial_pml2[2][512];
-PAGEALIGN static uint64_t s_kernel_initial_pml1[2][512];
-static intmax_t s_next_pdid = 0;
-static page_directory_t s_kernel_initial_pd;
-
-page_directory_t *current_page_directory;
-
-struct PageStateCache {
- page_directory_t *pd;
- size_t pmli[4];
- pmle_t *pml[4];
-} s_state_cache;
-
-physptr_t
-mem_linear_tophys_koffset(uintptr_t virt)
-{
- return (virt - boot_kernel_virtual_base) + boot_kernel_physical_address;
-}
-
-uintptr_t
-mem_phys_tolinear(physptr_t phys)
-{
- return (uintptr_t)(phys + 0xFFFF800000000000ULL);
-}
-
-static size_t
-s_paging_pmli(size_t l, uintptr_t addr)
-{
- size_t shift = (12 + (9 * l));
- return (addr & (0x1FFULL << shift)) >> shift;
-}
-
-static pmle_t*
-s_paging_fetch_table(pmle_t *pml, size_t l, uintptr_t virt)
-{
- size_t pmli = s_paging_pmli(l, virt);
- if(s_state_cache.pmli[l] == pmli && s_state_cache.pml[l] != NULL)
- return s_state_cache.pml[l];
-
- pmle_t entry = pml[pmli];
- bool entry_new = false;
- if(!entry.p) {
- entry_new = true;
- entry.value = mem_phys_alloc(1);
- entry.p = 1;
- entry.rw = 1;
- entry.us = 1;
- pml[pmli] = entry;
- }
- pmle_t *table = (pmle_t*)(mem_phys_tolinear(entry.paddr << 12));
- if(entry_new) memset(table, 0, PAGE_SIZE);
-
- s_state_cache.pmli[l] = pmli;
- s_state_cache.pml[l] = table;
- return table;
-}
-
-static void
-s_paging_cache_tables(page_directory_t *pd, uintptr_t virt)
-{
- pmle_t *pml4 = (pmle_t*)pd->virt;
- if(s_state_cache.pd != pd) memset(&s_state_cache, 0, sizeof(s_state_cache));
-
- pmle_t *pml3 = s_paging_fetch_table(pml4, 3, virt);
- pmle_t *pml2 = s_paging_fetch_table(pml3, 2, virt);
- pmle_t *pml1 = s_paging_fetch_table(pml2, 1, virt);
-}
-
-static pmle_t*
-s_paging_get_table(pmle_t *pt, size_t l, uintptr_t virt)
-{
- if(pt == NULL) return NULL;
- size_t pmli = s_paging_pmli(l, virt);
- if(s_state_cache.pmli[l] == pmli && s_state_cache.pml[l] != NULL)
- return s_state_cache.pml[l];
-
- pmle_t entry = pt[pmli];
- if(!entry.p) return NULL;
- return (pmle_t*)(mem_phys_tolinear(entry.paddr << 12));
-}
-
-page_mapping_t
-mem_get_mapping_as(page_directory_t *pd, uintptr_t addr)
-{
- spinlock_acquire(pd->lock);
- page_mapping_t mapping = { 0 };
-
- pmle_t *pml4 = (pmle_t*)pd->virt;
- if(s_state_cache.pd != pd) memset(&s_state_cache, 0, sizeof(s_state_cache));
-
- pmle_t *pml3 = s_paging_get_table(pml4, 3, addr);
- pmle_t *pml2 = s_paging_get_table(pml3, 2, addr);
- pmle_t *pml1 = s_paging_get_table(pml2, 1, addr);
- if(pml1 == NULL) goto release_return;
-
- size_t pml1i = s_paging_pmli(0, addr);
- pmle_t pml1e = pml1[pml1i];
-
- mapping = (page_mapping_t) {
- .phys = (pml1e.paddr << 12) & ~PAGE_MASK,
- .pf = {
- .present = pml1e.p,
- .writeable = pml1e.rw,
- .useraccess = pml1e.us,
- .executable = !pml1e.xd
- }
- };
-release_return:
- spinlock_release(pd->lock);
- return mapping;
-}
-
-page_mapping_t mem_get_mapping(uintptr_t addr)
-{ return mem_get_mapping_as(current_page_directory, addr); }
-
-
-bool
-mem_check_ptr(const void *ptr)
-{
- return mem_get_mapping((uintptr_t)ptr).pf.present != 0;
-}
-
-void
-mem_set_mapping_as(page_directory_t *pd, page_mapping_t mapping, uintptr_t virt)
-{
- spinlock_acquire(pd->lock);
- s_paging_cache_tables(pd, virt);
- pmle_t *pml1 = s_state_cache.pml[0];
- size_t pml1i = s_paging_pmli(0, virt);
-
- pml1[pml1i] = (pmle_t) {
- .p = mapping.pf.present,
- .rw = mapping.pf.writeable,
- .us = mapping.pf.useraccess,
- .xd = !mapping.pf.executable,
- .paddr = mapping.phys >> 12
- };
- spinlock_release(pd->lock);
-}
-
-void mem_set_mapping(page_mapping_t mapping, uintptr_t virt)
-{ mem_set_mapping_as(current_page_directory, mapping, virt); }
-
-void
-mem_ensure_range_as(page_directory_t *pd, uintptr_t from, uintptr_t to, page_flags_t flg)
-{
- spinlock_acquire(pd->lock);
- from &= ~(PAGE_SIZE - 1);
-
- if(to < from) to = from;
- size_t pages = (to - from) >> 12;
- if(pages == 0) pages = 1;
- for(size_t i = 0; i < pages; i++) {
- uintptr_t waddr = from + (i << 12);
- s_paging_cache_tables(pd, waddr);
- pmle_t *pml1 = s_state_cache.pml[1];
- size_t pml1i = s_paging_pmli(0, waddr);
-
- if(!pml1[pml1i].p) {
- physptr_t phys = mem_phys_alloc(1);
- pml1[pml1i] = (pmle_t) {
- .p = flg.present,
- .rw = flg.writeable,
- .us = flg.useraccess,
- .xd = !flg.executable,
- .paddr = phys >> 12
- };
- }
- }
- spinlock_release(pd->lock);
-}
-
-void mem_ensure_range(uintptr_t from, uintptr_t to, page_flags_t flg)
-{ mem_ensure_range_as(current_page_directory, from, to, flg); }
-
-struct Registers*
-s_pagefault_handler(struct Registers *state)
-{
- extern uint64_t __isr_err;
-
- uintptr_t fault_addr = 0;
- __asm__ volatile("movq %%cr2, %0": "=r"(fault_addr));
-
- bool present = __isr_err & 1;
- bool write = __isr_err & 2;
- bool user = __isr_err & 4;
- bool fetch = __isr_err & 16;
-
- klogf("Page fault at %016X\n", fault_addr);
- klogf("%s %s from a %s address\n",
- user ? "user" : "kernel",
- write ? "wrote" : "read",
- present ? "present" : "non-present");
-
- kpanic("Unhandled page fault at %016X\n", state->ip);
- return state;
-}
-
-void
-mem_paging_setup(void)
-{
- memset(s_kernel_initial_pml4, 0, PAGE_SIZE);
- memset(s_kernel_initial_pml3, 0, 2 * PAGE_SIZE);
- memset(s_kernel_initial_pml2, 0, 2 * PAGE_SIZE);
- memset(s_kernel_initial_pml1, 0, PAGE_SIZE);
- s_kernel_initial_pd = (page_directory_t){
- .phys = mem_linear_tophys_koffset((uintptr_t)&s_kernel_initial_pml4),
- .virt = (union PageEntry*)&s_kernel_initial_pml4,
- .ref = 1,
- .id = s_next_pdid++
- };
- current_page_directory = &s_kernel_initial_pd;
-
- /* Map first few GiBs */
- s_kernel_initial_pml4[256] =
- mem_linear_tophys_koffset((uintptr_t)&s_kernel_initial_pml3[0])
- | 3;
- s_kernel_initial_pml3[0][0] =
- mem_linear_tophys_koffset((uintptr_t)&s_kernel_initial_pml2[0])
- | 3;
- for(int i = 0; i < 512; i++) {
- s_kernel_initial_pml2[0][i] = (i * (PAGE_SIZE * 512)) | 0x80 | 3;
- }
-
- size_t kernel_pml4e = (boot_kernel_virtual_base >> (39));
- size_t kernel_pml3e = (boot_kernel_virtual_base >> (30)) % 512;
- size_t kernel_pml2e = (boot_kernel_virtual_base >> (21)) % 512;
- size_t kernel_npages = ((((uintptr_t)&_kernel_end) - boot_kernel_virtual_base) >> 12) + 1;
- klogf("Kernel has %i pages\n", kernel_npages);
-
- /* Map kernel pages */
- s_kernel_initial_pml4[511] =
- mem_linear_tophys_koffset((uintptr_t)&s_kernel_initial_pml3[1]) | 3;
- s_kernel_initial_pml3[1][kernel_pml3e] =
- mem_linear_tophys_koffset((uintptr_t)&s_kernel_initial_pml2[1]) | 3;
- s_kernel_initial_pml2[1][kernel_pml2e] =
- mem_linear_tophys_koffset((uintptr_t)&s_kernel_initial_pml1[0]) | 3;
- for(int i = 0; i < kernel_npages; i++) {
- s_kernel_initial_pml1[0][i] = (i * PAGE_SIZE) + boot_kernel_physical_address | 3;
- }
-
- int_set_handler(14, s_pagefault_handler);
- __asm__ volatile("mov %0, %%cr3":: "r"(s_kernel_initial_pd.phys));
-}
generated by cgit v1.2.1 (git 2.18.0) at 2024-06-28 19:42:56 +0000