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Diffstat (limited to 'kernel/mm/physical_mm/memory_map.cc')
-rw-r--r-- | kernel/mm/physical_mm/memory_map.cc | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/kernel/mm/physical_mm/memory_map.cc b/kernel/mm/physical_mm/memory_map.cc new file mode 100644 index 0000000..6284173 --- /dev/null +++ b/kernel/mm/physical_mm/memory_map.cc @@ -0,0 +1,60 @@ +/* + * bubbl + * Copyright (C) 2025 Raghuram Subramani <raghus2247@gmail.com> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <mm/physical_mm.h> +#include <stdbool.h> +#include <stdint.h> + +namespace PhysicalMM +{ + +/* Marks the block as 'used' */ +void +set_used(const uint32_t bit, uint32_t *total_free_blocks, uint32_t *memory_map) +{ + uint32_t memory_map_index = bit / BITMAP_ENTRY_SIZE; + uint32_t bitmask = 1 << (bit % BITMAP_ENTRY_SIZE); + (*total_free_blocks)--; + memory_map[memory_map_index] |= bitmask; +} + +/* Marks the block as 'unused' */ +void +set_usable(const uint32_t bit, + uint32_t *total_free_blocks, + uint32_t *memory_map) +{ + uint32_t memory_map_index = bit / BITMAP_ENTRY_SIZE; + uint32_t bitmask = 1 << (bit % BITMAP_ENTRY_SIZE); + (*total_free_blocks)++; + memory_map[memory_map_index] &= ~bitmask; +} + +/* Returns: + * True if the bit is set (block is in use) + * False if the bit is unset (block isn't in use) + */ +bool +test_bit(const uint32_t bit, uint32_t *memory_map) +{ + uint32_t memory_map_index = bit / BITMAP_ENTRY_SIZE; + uint32_t bitmask = 1 << (bit % BITMAP_ENTRY_SIZE); + return memory_map[memory_map_index] & bitmask; +} + +} |