diff options
| -rw-r--r-- | kernel/fs/ext2.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/kernel/fs/ext2.c b/kernel/fs/ext2.c index f2e7ba7..04108f4 100644 --- a/kernel/fs/ext2.c +++ b/kernel/fs/ext2.c @@ -78,20 +78,27 @@ void ext2_read_block(u32 block, void *address, size_t size, size_t offset) { cached_read_block(block, address, size, offset); } -void ext2_write_block(u32 block, void *address, size_t size, size_t offset) { - // Invalidate a old cache +void ext2_write_block(u32 block, u8 *address, size_t size, size_t offset) { + assert(offset + size <= block_byte_size); + int cache_index = -1; for (int i = 0; i < NUM_BLOCK_CACHE; i++) { if (cache[i].block_num == block) { - cache[i].block_num = 0; + cache_index = i; break; } } + if (-1 != cache_index) { + memcpy(cache[cache_index].block + offset, address, size); + raw_vfs_pwrite(mount_fd, cache[cache_index].block, block_byte_size, + block * block_byte_size); + return; + } raw_vfs_pwrite(mount_fd, address, size, block * block_byte_size + offset); } void write_group_descriptor(u32 group_index, bgdt_t *block_group) { int starting_block = (1024 == block_byte_size) ? 2 : 1; - ext2_write_block(starting_block, block_group, sizeof(bgdt_t), + ext2_write_block(starting_block, (u8 *)block_group, sizeof(bgdt_t), group_index * sizeof(bgdt_t)); } @@ -418,10 +425,8 @@ int get_free_inode(int allocate) { void write_to_indirect_block(u32 indirect_block, u32 index, u32 new_block) { index %= INDIRECT_BLOCK_CAPACITY; - u32 buffer[INDIRECT_BLOCK_CAPACITY]; - ext2_read_block(indirect_block, buffer, sizeof(buffer), 0); - buffer[index] = new_block; - ext2_write_block(indirect_block, buffer, sizeof(buffer), 0); + ext2_write_block(indirect_block, (u8 *)&new_block, sizeof(u32), + index * sizeof(u32)); } int ext2_allocate_block(inode_t *inode, u32 index) { @@ -455,8 +460,7 @@ int ext2_allocate_block(inode_t *inode, u32 index) { inode->double_indirect_block_pointer = n; } - u32 value = get_singly_block_index(inode->double_indirect_block_pointer, - index / INDIRECT_BLOCK_CAPACITY); + u32 value; if (0 == (index % INDIRECT_BLOCK_CAPACITY)) { int n = get_free_block(1 /*true*/); if (-1 == n) { @@ -465,6 +469,9 @@ int ext2_allocate_block(inode_t *inode, u32 index) { write_to_indirect_block(inode->double_indirect_block_pointer, index / INDIRECT_BLOCK_CAPACITY, n); value = n; + } else { + value = get_singly_block_index(inode->double_indirect_block_pointer, + index / INDIRECT_BLOCK_CAPACITY); } write_to_indirect_block(value, index, b); |