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hilbert-os/kernel/source/application.cpp

550 lines
16 KiB
C++

#include <hilbert/kernel/application.hpp>
#include <hilbert/kernel/paging.hpp>
#include <hilbert/kernel/panic.hpp>
//TODO - scheduling.
namespace hilbert::kernel::application {
process::process() : framebuffer_vaddr(0) {
uint64_t p4_vaddr;
paging::map_new_kernel_page(p4_vaddr, p4_paddr);
p4 = (uint64_t *)p4_vaddr;
uint64_t p3_paddr;
uint64_t p3_vaddr;
paging::map_new_kernel_page(p3_vaddr, p3_paddr);
p3 = (uint64_t *)p3_vaddr;
for (int i = 1; i < 511; ++i)
p4[i] = 0;
p4[0] = paging::encode_pte(p3_paddr, true, true, true);
p4[511] = paging::kernel_p4e;
for (int i = 0; i < 512; ++i) {
p3[i] = 0;
p2s[i] = 0;
p1s[i] = 0;
p1es_to_free_on_exit[i] = 0;
}
}
void process::map_page(uint64_t vaddr, uint64_t paddr,
bool write, bool execute, bool free_pram_on_exit
) {
uint64_t i = ((vaddr / 4096) / 512) / 512;
uint64_t j = ((vaddr / 4096) / 512) % 512;
uint64_t k = (vaddr / 4096) % 512;
if (p2s[i] == 0) {
uint64_t p2_paddr;
uint64_t p2_vaddr;
paging::map_new_kernel_page(p2_vaddr, p2_paddr);
p3[i] = paging::encode_pte(p2_paddr, true, true, true);
p2s[i] = (uint64_t *)p2_vaddr;
p1s[i] = new uint64_t *[512];
p1es_to_free_on_exit[i] = new bool *[512];
for (int u = 0; u < 512; ++u) {
p2s[i][u] = 0;
p1s[i][u] = 0;
p1es_to_free_on_exit[i][u] = 0;
}
}
if (p2s[i][j] == 0) {
uint64_t p1_paddr;
uint64_t p1_vaddr;
paging::map_new_kernel_page(p1_vaddr, p1_paddr);
p2s[i][j] = paging::encode_pte(p1_paddr, true, true, true);
p1s[i][j] = (uint64_t *)p1_vaddr;
p1es_to_free_on_exit[i][j] = new bool[512];
for (int u = 0; u < 512; ++u) {
p1s[i][j][u] = 0;
p1es_to_free_on_exit[i][j][u] = false;
}
}
p1s[i][j][k] = paging::encode_pte(paddr, true, write, execute);
p1es_to_free_on_exit[i][j][k] = free_pram_on_exit;
}
bool process::is_page_owned(uint64_t vaddr) {
uint64_t i = ((vaddr / 4096) / 512) / 512;
uint64_t j = ((vaddr / 4096) / 512) % 512;
uint64_t k = (vaddr / 4096) % 512;
return
i < 512 && p1s[i] != 0 && p1s[i][j] != 0 &&
p1s[i][j][k] != 0 && p1es_to_free_on_exit[i][j][k];
}
uint64_t process::get_free_vaddr_pages(uint64_t count) {
uint64_t start = 0x200000 / 4096;
uint64_t length = 0;
while (start + length <= 0x8000000000 / 4096) {
if (length == count)
return start * 4096;
int i = ((start + length) / 512) / 512;
int j = ((start + length) / 512) % 512;
int k = (start + length) % 512;
if (p1s[i] == 0 || p1s[i][j] == 0 || p1s[i][j][k] == 0)
++length;
else {
start += length + 1;
length = 0;
}
}
//TODO: handle out of memory
return 0;
}
uint64_t process::count_mapped_vram_pages() {
uint64_t count = 0;
for (int i = 0; i < 512; ++i)
if (p1s[i] != 0)
for (int j = 0; j < 512; ++j)
if (p1s[i][j] != 0)
for (int k = 0; k < 512; ++k)
if (p1s[i][j][k] != 0)
++count;
return count;
}
utility::id_allocator<process *> *processes;
utility::queue<thread *> *paused_threads;
utility::queue<thread *> *threads_waiting_for_input;
thread *running_thread;
utility::list<socket_listener *> *all_socket_listeners;
static uint8_t correct_magic[16] = {
0x7f, 0x45, 0x4c, 0x46, 0x02, 0x01, 0x01, 0x00,
0x02, 0x00, 0x3e, 0x00, 0x01, 0x00, 0x00, 0x00
};
#define READ(a, b, c) \
{ \
storage::fs_result _result = file.read_file(a, b, c); \
if (_result != storage::fs_result::success) \
return stream_result::io_error; \
}
#define TRY_MAR(expr) \
{ \
storage::fs_result _result = expr; \
if (_result != storage::fs_result::success) { \
delete process_out; \
return stream_result::io_error; \
} \
}
struct load_info {
uint64_t foffset;
uint64_t fsize;
uint64_t vaddr;
uint64_t voffset;
uint64_t vpages;
bool writable;
bool executable;
};
storage::fs_result map_and_read(
const vfile::vfile &file, process *process, uint64_t vaddr, uint64_t faddr,
uint64_t len, bool writable, bool executable
) {
uint64_t page_vaddr = vaddr & ~4095;
int at_start = vaddr & 4095;
int at_end = 4096 - len - at_start;
uint64_t page_paddr = paging::take_pram_page();
process->map_page(page_vaddr, page_paddr, writable, executable, true);
uint64_t page_kvaddr = paging::find_unmapped_vram_region(1);
paging::map_kernel_page(page_paddr, page_kvaddr, true, false);
storage::fs_result result = storage::fs_result::success;
if (at_start) {
uint8_t *blank = (uint8_t *)page_kvaddr;
for (int i = 0; i < at_start; ++i)
blank[i] = 0;
}
if (len != 0)
result = file.read_file(faddr, len, (void *)(page_kvaddr + at_start));
if (at_end) {
uint8_t *blank = (uint8_t *)(page_kvaddr + at_start + len);
for (int i = 0; i < at_end; ++i)
blank[i] = 0;
}
paging::unmap_kernel_page(page_kvaddr);
return result;
}
stream_result create_application(
const vfile::vfile &file, process *&process_out, thread *&thread_out
) {
uint8_t magic[16];
if (file.dir_entry.type != storage::file_type::regular_file)
return stream_result::not_a_regular_file;
if (file.dir_entry.length < 64)
return stream_result::not_an_executable;
READ(0, 8, magic)
READ(16, 8, magic + 8)
for (int i = 0; i < 16; ++i)
if (magic[i] != correct_magic[i])
return stream_result::not_an_executable;
uint64_t entry_point;
uint64_t phead_start;
uint16_t phead_entry_size;
uint16_t phead_entry_count;
READ(24, 8, &entry_point)
READ(32, 8, &phead_start)
READ(54, 2, &phead_entry_size)
READ(56, 2, &phead_entry_count)
if (file.dir_entry.length <
phead_start + phead_entry_size * phead_entry_count)
return stream_result::not_an_executable;
utility::vector<load_info> load_infos;
for (uint16_t i = 0; i < phead_entry_count; ++i) {
uint64_t entry_start = phead_start + phead_entry_size * i;
uint32_t seg_type;
READ(entry_start, 4, &seg_type)
if (seg_type != 1)
continue;
uint64_t foffset;
uint64_t vaddr;
uint64_t voffset;
uint64_t fsize;
uint64_t vsize;
uint32_t flags;
READ(entry_start + 8, 8, &foffset)
READ(entry_start + 16, 8, &vaddr)
READ(entry_start + 32, 8, &fsize)
READ(entry_start + 40, 8, &vsize)
READ(entry_start + 4, 4, &flags)
voffset = vaddr % 4096;
vaddr -= voffset;
if (vsize == 0)
continue;
if (file.dir_entry.length < foffset + fsize)
return stream_result::not_an_executable;
if (fsize > vsize)
return stream_result::not_an_executable;
if (vaddr < 0x200000)
return stream_result::not_an_executable;
uint64_t vpages = (voffset + vsize - 1) / 4096 + 1;
if (vaddr + vpages * 4096 > 0x8000000000)
return stream_result::not_an_executable;
load_info info = {
.foffset = foffset,
.fsize = fsize,
.vaddr = vaddr,
.voffset = voffset,
.vpages = vpages,
.writable = (flags & 2) == 2,
.executable = (flags & 1) == 1
};
load_infos.add_end(info);
}
process_out = new process();
for (unsigned i = 0; i < load_infos.count; ++i) {
const auto &info = load_infos.buffer[i];
uint64_t vaddr = info.vaddr + info.voffset;
uint64_t faddr = info.foffset;
uint64_t v_remaining = info.vpages * 4096 - info.voffset;
uint64_t f_remaining = info.fsize;
if (info.voffset != 0) {
int to_read = info.fsize < 4096 - info.voffset
? info.fsize : 4096 - info.voffset;
if (to_read > 0) {
TRY_MAR(map_and_read(file, process_out, vaddr, faddr, to_read,
info.writable, info.executable))
vaddr += to_read;
faddr += to_read;
v_remaining -= to_read;
f_remaining -= to_read;
}
}
while (f_remaining > 0) {
int to_read = f_remaining < 4096 ? f_remaining : 4096;
TRY_MAR(map_and_read(file, process_out, vaddr, faddr, to_read,
info.writable, info.executable))
vaddr += to_read;
faddr += to_read;
v_remaining -= to_read;
f_remaining -= to_read;
}
if (vaddr & 4095) {
v_remaining -= 4096 - (vaddr & 4095);
vaddr += 4096 - (vaddr & 4095);
}
while (v_remaining > 0) {
map_and_read(
file, process_out, vaddr, 0, 0, info.writable, info.executable);
vaddr += 4096;
v_remaining -= 4096;
}
}
for (uint64_t vaddr = 0x1000; vaddr < 0x1ff000; vaddr += 4096) {
uint64_t paddr = paging::take_pram_page();
uint64_t kvaddr = paging::find_unmapped_vram_region(1);
paging::map_kernel_page(paddr, kvaddr, true, false);
uint8_t *p = (uint8_t *)kvaddr;
for (int i = 0; i < 4096; ++i)
p[i] = 0;
paging::unmap_kernel_page(kvaddr);
process_out->map_page(vaddr, paddr, true, false, true);
}
thread_out = new thread();
process_out->threads.insert_end(thread_out);
thread_out->the_process = process_out;
thread_out->state = thread_state::paused;
thread_out->cpu.rax = 0;
thread_out->cpu.rbx = 0;
thread_out->cpu.rcx = 0;
thread_out->cpu.rdx = 0;
thread_out->cpu.rdi = 0;
thread_out->cpu.rsi = 0;
thread_out->cpu.rbp = 0;
thread_out->cpu.rsp = 0x1ff000;
thread_out->cpu.r8 = 0;
thread_out->cpu.r9 = 0;
thread_out->cpu.r10 = 0;
thread_out->cpu.r11 = 0;
thread_out->cpu.r12 = 0;
thread_out->cpu.r13 = 0;
thread_out->cpu.r14 = 0;
thread_out->cpu.r15 = 0;
thread_out->cpu.rflags = 0x200;
thread_out->cpu.rip = entry_point;
thread_out->cpu.cr3 = process_out->p4_paddr;
thread_out->cpu.in_syscall = false;
return stream_result::success;
}
extern "C" void init_applications_asm();
void init_applications() {
processes = new utility::id_allocator<process *>();
paused_threads = new utility::queue<thread *>();
threads_waiting_for_input = new utility::queue<thread *>();
all_socket_listeners = new utility::list<socket_listener *>();
init_applications_asm();
}
//only called from non-interruptable contexts.
//cpu argument not on stack.
extern "C" [[noreturn]] void resume_thread(const cpu_state &cpu);
extern "C" void *copy_syscall_stack(uint8_t *rsp) {
uint64_t size = 0xfffffffffffff000 - (uint64_t)rsp;
uint8_t *buffer = new uint8_t[size];
for (uint64_t i = 0; i < size; ++i)
buffer[i] = rsp[i];
return buffer;
}
extern "C" void restore_syscall_stack(const uint8_t *from, uint8_t *rsp) {
uint64_t size = 0xfffffffffffff000 - (uint64_t)rsp;
for (uint64_t i = 0; i < size; ++i)
rsp[i] = from[i];
delete[] from;
}
thread::~thread() {
for (auto *p = the_process->threads.first; p; p = p->next)
if (p->value == this) {
the_process->threads.remove(p);
break;
}
if (the_process->threads.first == 0) {
the_process->exit_code = exit_code;
the_process->cleanup();
}
if (state != thread_state::running)
panic(0x9af5e6);
}
[[noreturn]] void resume_next() {
while (paused_threads->count == 0)
asm volatile ("sti\nhlt\ncli");
auto *t = paused_threads->take();
running_thread = t;
t->state = thread_state::running;
resume_thread(t->cpu);
}
void process::end_process(unsigned exit_code) {
while (threads.first != 0)
delete threads.first->value;
this->exit_code = exit_code;
cleanup();
}
void process::cleanup() {
//TODO
panic(0x9af5e6);
}
socket_stream::socket_stream(socket *sock, bool are_we_b)
: sock(sock), are_we_b(are_we_b),
our_threads_waiting_to_read(are_we_b
? sock->process_b_threads_waiting_to_read
: sock->process_a_threads_waiting_to_read),
their_threads_waiting_to_read(are_we_b
? sock->process_a_threads_waiting_to_read
: sock->process_b_threads_waiting_to_read),
them_to_us(are_we_b ? sock->a_to_b : sock->b_to_a),
us_to_them(are_we_b ? sock->b_to_a : sock->a_to_b),
them_closed(are_we_b ? sock->a_closed : sock->b_closed),
us_closed(are_we_b ? sock->b_closed : sock->a_closed) {}
stream_result socket_stream::seek(seek_origin, int64_t) {
return stream_result::not_seekable;
}
stream_result socket_stream::read(uint64_t count, void *into) {
uint8_t *buffer = (uint8_t *)into;
for (uint64_t i = 0; i < count; ++i) {
while (them_to_us.count == 0) {
if (them_closed)
return stream_result::other_end_closed;
if (!save_thread_state(running_thread->cpu)) {
running_thread->state = thread_state::waiting;
our_threads_waiting_to_read.insert(running_thread);
resume_next();
}
}
buffer[i] = them_to_us.take();
}
return stream_result::success;
}
stream_result socket_stream::write(uint64_t count, const void *from) {
if (them_closed)
return stream_result::other_end_closed;
const uint8_t *buffer = (const uint8_t *)from;
for (uint64_t i = 0; i < count; ++i) {
if (their_threads_waiting_to_read.count > 0) {
auto *ot = their_threads_waiting_to_read.take();
ot->state = thread_state::paused;
paused_threads->insert(ot);
}
us_to_them.insert(buffer[i]);
}
return stream_result::success;
}
stream_result socket_stream::get_length(uint64_t &) {
return stream_result::not_sized;
}
stream_result socket_stream::set_length(uint64_t) {
return stream_result::not_sized;
}
socket_stream::~socket_stream() {
if (our_threads_waiting_to_read.count > 0)
panic(0x9af5e6);
if (them_closed)
delete sock;
else {
us_closed = true;
while (their_threads_waiting_to_read.count > 0) {
auto *t = their_threads_waiting_to_read.take();
t->state = thread_state::paused;
paused_threads->insert(t);
}
}
}
vfile_stream::vfile_stream(vfile::vfile &&file)
: file(utility::move(file)), offset(0) {}
stream_result vfile_stream::seek(seek_origin origin, int64_t offset) {
uint64_t start_at = {};
switch (origin) {
case seek_origin::beginning:
start_at = 0;
break;
case seek_origin::end:
start_at = file.dir_entry.length;
break;
case seek_origin::current_position:
start_at = this->offset;
break;
}
if (offset < 0 && (uint64_t)-offset > start_at)
return stream_result::out_of_bounds;
if (offset + start_at > file.dir_entry.length)
return stream_result::out_of_bounds;
this->offset = start_at + offset;
return stream_result::success;
}
stream_result vfile_stream::read(uint64_t count, void *into) {
if (offset + count > file.dir_entry.length)
return stream_result::out_of_bounds;
if (file.read_file(offset, count, into) != storage::fs_result::success)
return stream_result::io_error;
offset += count;
return stream_result::success;
}
stream_result vfile_stream::write(uint64_t count, const void *from) {
if (offset + count > file.dir_entry.length)
return stream_result::out_of_bounds;
(void)from;
panic(0x9af5e6);
}
stream_result vfile_stream::get_length(uint64_t &out) {
out = file.dir_entry.length;
return stream_result::success;
}
stream_result vfile_stream::set_length(uint64_t to) {
(void)to;
panic(0x9af5e6);
}
}