diff options
Diffstat (limited to 'libraries/euler/allocator.cpp')
-rw-r--r-- | libraries/euler/allocator.cpp | 147 |
1 files changed, 0 insertions, 147 deletions
diff --git a/libraries/euler/allocator.cpp b/libraries/euler/allocator.cpp deleted file mode 100644 index 5242df1..0000000 --- a/libraries/euler/allocator.cpp +++ /dev/null @@ -1,147 +0,0 @@ -#include <euler/syscall.hpp> - -//i guess we could figure out which parts of the pages the kernel allocated to -//load the application were not actually needed and add those to the memory -//that is available to be allocated, but whatever. - -namespace euler::allocator { - - struct block_info { - //vaddr, divisible by size - uint64_t start; - //power of 2, 0 for unused - uint64_t size; - }; - - struct block_info_page { - block_info infos[255]; - block_info_page *next; - }; - - static_assert(sizeof(block_info_page) == 4088); - - static block_info_page *first_bi_page = 0; - - static block_info *try_find_block(uint64_t start, uint64_t size) { - for (block_info_page *bip = first_bi_page; bip; bip = bip->next) - for (int i = 0; i < 255; ++i) - if (bip->infos[i].start == start && bip->infos[i].size == size) - return bip->infos + i; - return 0; - } - - static block_info *add_block(uint64_t start, uint64_t size) { - for (block_info_page *bip = first_bi_page; bip; bip = bip->next) - for (int i = 0; i < 255; ++i) - if (bip->infos[i].size == 0) { - bip->infos[i].start = start; - bip->infos[i].size = size; - return bip->infos + i; - } - block_info_page *new_bip = (block_info_page *)_syscall_get_new_pages(1); - new_bip->infos[0].start = start; - new_bip->infos[0].size = size; - for (int i = 1; i < 255; ++i) - new_bip->infos[i].size = 0; - new_bip->next = first_bi_page; - first_bi_page = new_bip; - return new_bip->infos; - } - - static block_info *find_minimal_block(uint64_t minimum_length) { - block_info *minimal_so_far = 0; - uint64_t length_so_far = UINT64_MAX; - for (block_info_page *bip = first_bi_page; bip; bip = bip->next) - for (int i = 0; i < 255; ++i) - if (bip->infos[i].size == minimum_length) - return bip->infos + i; - else if ( - bip->infos[i].size > minimum_length && - bip->infos[i].size < length_so_far - ) { - minimal_so_far = bip->infos + i; - length_so_far = bip->infos[i].size; - } - if (minimal_so_far != 0) - return minimal_so_far; - uint64_t pages_needed = (minimum_length - 1) / 4096 + 1; - void *block_start = _syscall_get_new_pages(pages_needed); - return add_block((uint64_t)block_start, pages_needed * 4096); - } - - static void deallocate_aligned(uint64_t start, uint64_t length) { - block_info *buddy = try_find_block(start ^ length, length); - if (buddy) { - buddy->size = 0; - deallocate_aligned(start & ~length, length * 2); - return; - } - add_block(start, length); - } - - static void deallocate(void *start, uint64_t length) { - uint64_t at = (uint64_t)start; - uint64_t left = length; - uint64_t i; - for (i = 1; i <= left; i *= 2) - if (at & i) { - deallocate_aligned(at, i); - at += i; - left -= i; - } - for (i /= 2; left > 0; i /= 2) - if (i <= left) { - deallocate_aligned(at, i); - at += i; - left -= i; - } - } - - [[nodiscard]] static void *allocate(uint64_t length) { - block_info *bi = find_minimal_block(length); - void *to_return = (void *)bi->start; - void *new_start = (void *)(bi->start + length); - uint64_t new_length = bi->size - length; - bi->size = 0; - deallocate(new_start, new_length); - return to_return; - } - - static void deallocate_with_length(void *start) { - uint64_t real_start = (uint64_t)start - 8; - deallocate((void *)real_start, *(uint64_t *)real_start); - } - - [[nodiscard]] static void *allocate_with_length(uint64_t length) { - uint64_t *real_start = (uint64_t *)allocate(length + 8); - *real_start = length + 8; - return real_start + 1; - } - -} - -using namespace euler::allocator; - -void operator delete[](void *start) { - deallocate_with_length(start); -} - -void operator delete(void *start) { - deallocate_with_length(start); -} - -void operator delete[](void *start, uint64_t) { - deallocate_with_length(start); -} - -void operator delete(void *start, uint64_t) { - deallocate_with_length(start); -} - -void *operator new[](uint64_t size) { - return allocate_with_length(size); -} - -void *operator new(uint64_t size) { - return allocate_with_length(size); -} |