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#include <hilbert/kernel/app-memory.hpp>
#include <hilbert/kernel/paging.hpp>
#include <hilbert/kernel/panic.hpp>
namespace hilbert::kernel {
app_memory::app_memory() {
uint64_t p3_paddr;
paging::map_new_kernel_page(p3, p3_paddr);
paging::map_new_kernel_page(p4, p4_paddr);
for (int i = 0; i < 512; ++i) {
p4[i] = 0;
p3[i] = 0;
p2s[i] = 0;
p1s[i] = 0;
pram_pages_to_free_on_exit[i] = 0;
}
p4[0] = paging::encode_pte(p3_paddr, true, true, true);
p4[511] = paging::kernel_p4e;
}
app_memory::~app_memory() {
//first we see if the p2s exist
for (int p3i = 0; p3i < 512; ++p3i)
if (p3[p3i]) {
//now we see if the p1s under this p2 exist
for (int p2i = 0; p2i < 512; ++p2i)
if (p2s[p3i][p2i]) {
//we see if the pages under this p1 need to be freed
for (int p1i = 0; p1i < 512; ++p1i)
if (pram_pages_to_free_on_exit[p3i][p2i][p1i])
paging::free_pram_page(
paging::pte_to_paddr(p1s[p3i][p2i][p1i]));
//we free the p1 and the pram list
paging::free_pram_page(paging::pte_to_paddr(p2s[p3i][p2i]));
paging::unmap_kernel_page((uint64_t)p1s[p3i][p2i]);
delete[] pram_pages_to_free_on_exit[p3i][p2i];
}
//free the p2, the p1 list, and the pram list list
paging::free_pram_page(paging::pte_to_paddr(p3[p3i]));
paging::unmap_kernel_page((uint64_t)p2s[p3i]);
delete[] p1s[p3i];
delete[] pram_pages_to_free_on_exit[p3i];
}
//finally, we free the p3 and the p4
paging::free_pram_page(paging::pte_to_paddr(p4[0]));
paging::unmap_kernel_page((uint64_t)p3);
paging::free_pram_page(p4_paddr);
paging::unmap_kernel_page((uint64_t)p4);
}
void app_memory::map_page(uint64_t vaddr, uint64_t paddr,
bool write, bool execute, bool free_pram_on_exit) {
int p1i = (vaddr >> 12) & 511;
int p2i = (vaddr >> 21) & 511;
int p3i = (vaddr >> 30) & 511;
if (p2s[p3i] == 0) {
uint64_t new_p2_paddr;
paging::map_new_kernel_page(p2s[p3i], new_p2_paddr);
p1s[p3i] = new v_page_table[512];
pram_pages_to_free_on_exit[p3i] = new bool *[512];
for (int i = 0; i < 512; ++i) {
p2s[p3i][i] = 0;
p1s[p3i][i] = 0;
pram_pages_to_free_on_exit[p3i][i] = 0;
}
p3[p3i] = paging::encode_pte(new_p2_paddr, true, true, true);
}
if (p1s[p3i][p2i] == 0) {
uint64_t new_p1_paddr;
paging::map_new_kernel_page(p1s[p3i][p2i], new_p1_paddr);
pram_pages_to_free_on_exit[p3i][p2i] = new bool[512];
for (int i = 0; i < 512; ++i) {
p1s[p3i][p2i][i] = 0;
pram_pages_to_free_on_exit[p3i][p2i][i] = false;
}
p2s[p3i][p2i] = paging::encode_pte(new_p1_paddr, true, true, true);
}
p1s[p3i][p2i][p1i] = paging::encode_pte(paddr, true, write, execute);
pram_pages_to_free_on_exit[p3i][p2i][p1i] = free_pram_on_exit;
}
void app_memory::unmap_page(uint64_t vaddr) {
int p1i = (vaddr >> 12) & 511;
int p2i = (vaddr >> 21) & 511;
int p3i = (vaddr >> 30) & 511;
if (pram_pages_to_free_on_exit[p3i][p2i][p1i]) {
pram_pages_to_free_on_exit[p3i][p2i][p1i] = false;
paging::free_pram_page(paging::pte_to_paddr(p1s[p3i][p2i][p1i]));
}
p1s[p3i][p2i][p1i] = 0;
}
bool app_memory::valid_to_read(
uint64_t vaddr_start, uint64_t vaddr_end, bool and_write) const {
if (vaddr_start > vaddr_end || vaddr_end > 0x8000000000)
return false;
vaddr_start = (vaddr_start / 4096) * 4096;
vaddr_end = (((vaddr_end - 1) / 4096) + 1) * 4096;
for (uint64_t vaddr = vaddr_start; vaddr < vaddr_end; ++vaddr) {
int p1i = (vaddr >> 12) & 511;
int p2i = (vaddr >> 21) & 511;
int p3i = (vaddr >> 30) & 511;
if (!p1s[p3i] || !p1s[p3i][p2i] || !(and_write
? (p1s[p3i][p2i][p1i] & 0x1) : p1s[p3i][p2i][p1i]))
return false;
}
return true;
}
uint64_t app_memory::get_free_vaddr_pages(uint64_t count) {
uint64_t vaddr = 0x1000;
uint64_t run = 0;
while (true) {
if (run == count)
return vaddr;
if (vaddr + (run + 1) * 4096 > 0x4000000000)
//TODO: handle out of virtual memory
panic(0x9af5e6);
if (valid_to_read(vaddr + run * 4096, vaddr + (run + 1) * 4096, false)) {
vaddr += (run + 1) * 4096;
run = 0;
}
else
++run;
}
}
uint64_t app_memory::map_new_stack() {
for (uint64_t base_vaddr = 0x4000000000;
base_vaddr < 0x8000000000; base_vaddr += 0x1000000)
if (!valid_to_read(base_vaddr + 4096, base_vaddr + 8192, false)) {
for (uint64_t vaddr = base_vaddr + 4096;
vaddr < base_vaddr + 0x1000000; vaddr += 4096) {
uint8_t *kvaddr;
uint64_t paddr;
paging::map_new_kernel_page(kvaddr, paddr);
for (int i = 0; i < 4096; ++i)
kvaddr[i] = 0;
paging::unmap_kernel_page(kvaddr);
map_page(vaddr, paddr, true, false, true);
}
return base_vaddr + 0x1000000;
}
//TODO: handle out of stacks
panic(0x9af5e6);
}
void app_memory::unmap_stack(uint64_t top) {
for (uint64_t vaddr = top - 0xfff000; vaddr < top; vaddr += 4096)
unmap_page(vaddr);
}
uint64_t app_memory::count_mapped_vram_pages() const {
uint64_t count = 0;
for (int p3i = 0; p3i < 512; ++p3i)
if (p3[p3i])
for (int p2i = 0; p2i < 512; ++p2i)
if (p2s[p3i][p2i])
for (int p1i = 0; p1i < 512; ++p1i)
if (p1s[p3i][p2i][p1i])
++count;
return count;
}
}
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