Moved the page allocator to be a global in paging.cpp and paging.hpp

diff --git a/src/kernel.cpp b/src/kernel.cpp
index 7e1ab9381975e4dca0579b739cb7f8597c38ebd4..1cfa10e273b5a2fd7cd787dcd1a6a1ffaf9604dd 100644 (file)
--- a/src/kernel.cpp
+++ b/src/kernel.cpp
@@ -28,10 +28,6 @@ void remove_some_mem(os::phys_ptr<os::paging::page> mem_start,
        }
 }
 
-os::paging::page one_past_end_page_for_page_allocator;
-os::paging::page_allocator page_allocator(os::phys_ptr<os::paging::page>(reinterpret_cast<uintptr_t>(&one_past_end_page_for_page_allocator) - 0xFFFFFFFF80000000));
-
-
 os::idt<32> idt;
 extern "C" void handler_impl_code(std::uint32_t err_code) {
        os::println("Interrupt !");
@@ -84,7 +80,7 @@ extern "C" void kmain(unsigned long magic, os::phys_ptr<const multiboot2::info_s
                                                        remove_some_mem(
                                                        s, e, info_start, info_end,
                                                        [] (auto s, auto e) {
-                                                               page_allocator.deallocate({.ptr = s, .size = std::uint64_t(e - s)});
+                                                               os::paging::page_allocator.deallocate({.ptr = s, .size = std::uint64_t(e - s)});
                                                        }
                                                        );
                                                }
@@ -107,14 +103,14 @@ extern "C" void kmain(unsigned long magic, os::phys_ptr<const multiboot2::info_s
 
        // Deallocate multiboot info structure: not usable anymore.
        if (info_pages_wholly_usable) {
-               page_allocator.deallocate({.ptr = info_start, .size = std::uint64_t(info_end - info_start)});
+               os::paging::page_allocator.deallocate({.ptr = info_start, .size = std::uint64_t(info_end - info_start)});
        } else if (info_start + 1 < info_end - 1) {
                // Ignore the first and last blocks: ensures all the RAM is truly usable.
-               page_allocator.deallocate({.ptr = info_start + 1, .size = std::uint64_t(info_end - info_start - 2)});
+               os::paging::page_allocator.deallocate({.ptr = info_start + 1, .size = std::uint64_t(info_end - info_start - 2)});
        }
 
        os::print("RAM:\n");
-       page_allocator.print_all();
+       os::paging::page_allocator.print_all();
 
        {
                os::isr_info isr_info[32];

diff --git a/src/paging.cpp b/src/paging.cpp
index e73cfb2369b88375f229dffb6ae7476d79c9b9a8..a09639c9678f91ab417a7fc96ea1af83f04edd75 100644 (file)
--- a/src/paging.cpp
+++ b/src/paging.cpp
@@ -1,12 +1,15 @@
 #include "paging.hpp"
 
-os::paging::page_allocator::page_allocator(phys_ptr<paging::page> one_past_end): begin_(one_past_end.get_phys_addr()), end_(begin_) {
+os::paging::page one_past_end_page_for_page_allocator;
+os::paging::page_allocator_t os::paging::page_allocator(os::phys_ptr<os::paging::page>(reinterpret_cast<uintptr_t>(&one_past_end_page_for_page_allocator) - 0xFFFFFFFF80000000));
+
+os::paging::page_allocator_t::page_allocator_t(phys_ptr<paging::page> one_past_end): begin_(one_past_end.get_phys_addr()), end_(begin_) {
        end_->prev = nullptr;
        end_->next = nullptr;
        end_->size = 1;
 }
 
-void os::paging::page_allocator::print_all() const {
+void os::paging::page_allocator_t::print_all() const {
        if (is_empty()) {
                os::println("No RAM left.");
        } else for (auto it = begin(); it != end(); it = it->next) {
@@ -17,7 +20,7 @@ void os::paging::page_allocator::print_all() const {
        }
 }
 
-os::paging::page_allocator::block os::paging::page_allocator::allocate(std::uint64_t count) {
+os::paging::page_allocator_t::block os::paging::page_allocator_t::allocate(std::uint64_t count) {
        for (auto it = begin(); it != end(); it = it->next) {
                if (count == it->size) {
                        erase(it);
@@ -35,7 +38,7 @@ os::paging::page_allocator::block os::paging::page_allocator::allocate(std::uint
        }
        return { .ptr = nullptr, .size = count };
 }
-void os::paging::page_allocator::deallocate(block b) {
+void os::paging::page_allocator_t::deallocate(block b) {
        if (b.ptr == nullptr) { return; }
        if (b.size == 0) { return; }
        const phys_ptr<page> b_it{b.ptr.get_phys_addr()};
@@ -44,13 +47,13 @@ void os::paging::page_allocator::deallocate(block b) {
        try_merge_next(try_merge_prev(insert(it, b)));
 }
 
-bool os::paging::page_allocator::is_empty() const { return begin() == end(); }
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::begin() { return begin_; }
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::end()   { return end_;   }
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::begin() const { return begin_; }
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::end()   const { return end_;   }
+bool os::paging::page_allocator_t::is_empty() const { return begin() == end(); }
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::begin() { return begin_; }
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::end()   { return end_;   }
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::begin() const { return begin_; }
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::end()   const { return end_;   }
 
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::insert(phys_ptr<page> it, block b) {
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::insert(phys_ptr<page> it, block b) {
        const phys_ptr<page> b_it{b.ptr.get_phys_addr()};
        if (it->prev == nullptr) {
                begin_ = b_it;
@@ -63,21 +66,21 @@ os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::inser
        b_it->size = b.size;
        return b_it;
 }
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::try_merge_prev(phys_ptr<page> it) {
-       os::assert(it != end(), "end() passed to page_allocator::try_merge_prev(phys_ptr<page>).");
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::try_merge_prev(phys_ptr<page> it) {
+       os::assert(it != end(), "end() passed to page_allocator_t::try_merge_prev(phys_ptr<page>).");
        if (it->prev == nullptr) { return it; }
        if (it->prev + it->prev->size != it) { return it; }
        it->prev->size += it->size;
        return erase(it)->prev;
 }
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::try_merge_next(phys_ptr<page> it) {
-       os::assert(it != end(), "end() passed to page_allocator::try_merge_next(phys_ptr<page>).");
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::try_merge_next(phys_ptr<page> it) {
+       os::assert(it != end(), "end() passed to page_allocator_t::try_merge_next(phys_ptr<page>).");
        if (it->next == end()) return it;
        try_merge_prev(it->next);
        return it;
 }
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::erase(phys_ptr<page> it) {
-       os::assert(it != end(), "end() passed to page_allocator::remove(phys_ptr<page>).");
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::erase(phys_ptr<page> it) {
+       os::assert(it != end(), "end() passed to page_allocator_t::remove(phys_ptr<page>).");
        if (it->prev == nullptr) {
                begin_ = it->next;
        } else {
@@ -86,10 +89,10 @@ os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::erase
        it->next->prev = it->prev;
        return it->next;
 }
-os::phys_ptr<os::paging::page_allocator::page> os::paging::page_allocator::split_at_offset(phys_ptr<page> it, std::size_t offset) {
-       os::assert(it != end(), "end() passed to page_allocator::split_at_offset(phys_ptr<page>, std::size_t).");
-       os::assert(offset < it->size, "offset passed to page_allocator::split_at_offset(phys_ptr<page>, std::size_t) was too big.");
-       os::assert(offset != 0, "offset 0 passed to page_allocator::split_at_offset(phys_ptr<page>, std::size_t).");
+os::phys_ptr<os::paging::page_allocator_t::page> os::paging::page_allocator_t::split_at_offset(phys_ptr<page> it, std::size_t offset) {
+       os::assert(it != end(), "end() passed to page_allocator_t::split_at_offset(phys_ptr<page>, std::size_t).");
+       os::assert(offset < it->size, "offset passed to page_allocator_t::split_at_offset(phys_ptr<page>, std::size_t) was too big.");
+       os::assert(offset != 0, "offset 0 passed to page_allocator_t::split_at_offset(phys_ptr<page>, std::size_t).");
        phys_ptr<page> after_split = it + offset;
        insert(it->next, block{ .ptr = phys_ptr<paging::page>{after_split.get_phys_addr()}, .size = it->size - offset });
        it->size = offset;

diff --git a/src/paging.hpp b/src/paging.hpp
index dcd3cee839760254cbd00a3f0f9ca851be9c43ca..9bc9f25c83ea99dd10d81443e5fa9917fac6aa88 100644 (file)
--- a/src/paging.hpp
+++ b/src/paging.hpp
@@ -131,11 +131,14 @@ struct __attribute__((aligned(0x1000))) paging_table {
        static_assert(order >= 0, "Paging table of negative order.");
        paging_entry<order> contents[512];
 };
+static_assert(sizeof(paging_table<0>) == 0x1000);
+static_assert(alignof(paging_table<0>) == 0x1000);
 
 template<>
-struct paging_table<-1> {
-       std::uint8_t contents[0x1000] = {0};
+struct __attribute__((aligned(0x1000))) paging_table<-1> {
 };
+static_assert(sizeof(paging_table<-1>) == 0x1000);
+static_assert(alignof(paging_table<-1>) == 0x1000);
 
 using PML4T = paging_table<3>;
 using PML4E = paging_entry<3>;
@@ -147,14 +150,17 @@ using PT = paging_table<0>;
 using PE = paging_entry<0>;
 using page = paging_table<-1>;
 
-class page_allocator {
+class page_allocator_t;
+extern page_allocator_t page_allocator;
+
+class page_allocator_t {
 public:
        struct block {
                phys_ptr<paging::page> ptr = nullptr;
                std::uint64_t size;
        };
 
-       page_allocator(phys_ptr<paging::page> one_past_end_page);
+       page_allocator_t(phys_ptr<paging::page> one_past_end_page);
        void print_all() const;
 
        block allocate(std::uint64_t page_count);