| /* |
| * Copyright (C) 2010 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "backed_block.h" |
| #include "sparse_defs.h" |
| |
| struct data_block { |
| u32 block; |
| u32 len; |
| void *data; |
| const char *filename; |
| int64_t offset; |
| struct data_block *next; |
| u32 fill_val; |
| u8 fill; |
| u8 pad1; |
| u16 pad2; |
| }; |
| |
| struct backed_block_list { |
| struct data_block *data_blocks; |
| struct data_block *last_used; |
| }; |
| |
| struct backed_block_list *backed_block_list_new(void) |
| { |
| struct backed_block_list *b = calloc(sizeof(struct backed_block_list), 1); |
| |
| return b; |
| } |
| |
| void backed_block_list_destroy(struct backed_block_list *b) |
| { |
| if (b->data_blocks) { |
| struct data_block *db = b->data_blocks; |
| while (db) { |
| struct data_block *next = db->next; |
| free((void*)db->filename); |
| |
| free(db); |
| db = next; |
| } |
| } |
| |
| free(b); |
| } |
| |
| static void queue_db(struct backed_block_list *b, struct data_block *new_db) |
| { |
| struct data_block *db; |
| |
| if (b->data_blocks == NULL) { |
| b->data_blocks = new_db; |
| return; |
| } |
| |
| if (b->data_blocks->block > new_db->block) { |
| new_db->next = b->data_blocks; |
| b->data_blocks = new_db; |
| return; |
| } |
| |
| /* Optimization: blocks are mostly queued in sequence, so save the |
| pointer to the last db that was added, and start searching from |
| there if the next block number is higher */ |
| if (b->last_used && new_db->block > b->last_used->block) |
| db = b->last_used; |
| else |
| db = b->data_blocks; |
| b->last_used = new_db; |
| |
| for (; db->next && db->next->block < new_db->block; db = db->next) |
| ; |
| |
| if (db->next == NULL) { |
| db->next = new_db; |
| } else { |
| new_db->next = db->next; |
| db->next = new_db; |
| } |
| } |
| |
| /* Queues a fill block of memory to be written to the specified data blocks */ |
| void queue_fill_block(struct backed_block_list *b, unsigned int fill_val, |
| unsigned int len, unsigned int block) |
| { |
| struct data_block *db = calloc(1, sizeof(struct data_block)); |
| if (db == NULL) { |
| error_errno("malloc"); |
| return; |
| } |
| |
| db->block = block; |
| db->len = len; |
| db->fill = 1; |
| db->fill_val = fill_val; |
| db->data = NULL; |
| db->filename = NULL; |
| db->next = NULL; |
| |
| queue_db(b, db); |
| } |
| |
| /* Queues a block of memory to be written to the specified data blocks */ |
| void queue_data_block(struct backed_block_list *b, void *data, unsigned int len, |
| unsigned int block) |
| { |
| struct data_block *db = malloc(sizeof(struct data_block)); |
| if (db == NULL) { |
| error_errno("malloc"); |
| return; |
| } |
| |
| db->block = block; |
| db->len = len; |
| db->data = data; |
| db->filename = NULL; |
| db->fill = 0; |
| db->next = NULL; |
| |
| queue_db(b, db); |
| } |
| |
| /* Queues a chunk of a file on disk to be written to the specified data blocks */ |
| void queue_data_file(struct backed_block_list *b, const char *filename, |
| int64_t offset, unsigned int len, unsigned int block) |
| { |
| struct data_block *db = malloc(sizeof(struct data_block)); |
| if (db == NULL) { |
| error_errno("malloc"); |
| return; |
| } |
| |
| db->block = block; |
| db->len = len; |
| db->filename = strdup(filename); |
| db->offset = offset; |
| db->data = NULL; |
| db->fill = 0; |
| db->next = NULL; |
| |
| queue_db(b, db); |
| } |
| |
| /* Iterates over the queued data blocks, calling data_func for each contiguous |
| data block, and file_func for each contiguous file block */ |
| void for_each_data_block(struct backed_block_list *b, |
| data_block_callback_t data_func, |
| data_block_file_callback_t file_func, |
| data_block_fill_callback_t fill_func, |
| void *priv, unsigned int block_size) |
| { |
| struct data_block *db; |
| u32 last_block = 0; |
| |
| for (db = b->data_blocks; db; db = db->next) { |
| if (db->block < last_block) |
| error("data blocks out of order: %u < %u", db->block, last_block); |
| last_block = db->block + DIV_ROUND_UP(db->len, block_size) - 1; |
| |
| if (db->filename) |
| file_func(priv, (u64)db->block * block_size, db->filename, db->offset, db->len); |
| else if (db->fill) |
| fill_func(priv, (u64)db->block * block_size, db->fill_val, db->len); |
| else |
| data_func(priv, (u64)db->block * block_size, db->data, db->len); |
| } |
| } |