| /* |
| * Copyright (C) 2007 Oracle. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public |
| * License v2 as published by the Free Software Foundation. |
| * |
| * 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, write to the |
| * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| * Boston, MA 021110-1307, USA. |
| */ |
| |
| #include <linux/bio.h> |
| #include <linux/pagemap.h> |
| #include <linux/highmem.h> |
| #include "ctree.h" |
| #include "disk-io.h" |
| #include "transaction.h" |
| #include "print-tree.h" |
| |
| #define MAX_CSUM_ITEMS(r,size) ((((BTRFS_LEAF_DATA_SIZE(r) - \ |
| sizeof(struct btrfs_item) * 2) / \ |
| size) - 1)) |
| int btrfs_insert_file_extent(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| u64 objectid, u64 pos, |
| u64 disk_offset, u64 disk_num_bytes, |
| u64 num_bytes, u64 offset, u64 ram_bytes, |
| u8 compression, u8 encryption, u16 other_encoding) |
| { |
| int ret = 0; |
| struct btrfs_file_extent_item *item; |
| struct btrfs_key file_key; |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| |
| path = btrfs_alloc_path(); |
| BUG_ON(!path); |
| file_key.objectid = objectid; |
| file_key.offset = pos; |
| btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY); |
| |
| ret = btrfs_insert_empty_item(trans, root, path, &file_key, |
| sizeof(*item)); |
| if (ret < 0) |
| goto out; |
| BUG_ON(ret); |
| leaf = path->nodes[0]; |
| item = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| btrfs_set_file_extent_disk_bytenr(leaf, item, disk_offset); |
| btrfs_set_file_extent_disk_num_bytes(leaf, item, disk_num_bytes); |
| btrfs_set_file_extent_offset(leaf, item, offset); |
| btrfs_set_file_extent_num_bytes(leaf, item, num_bytes); |
| btrfs_set_file_extent_ram_bytes(leaf, item, ram_bytes); |
| btrfs_set_file_extent_generation(leaf, item, trans->transid); |
| btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG); |
| btrfs_set_file_extent_compression(leaf, item, compression); |
| btrfs_set_file_extent_encryption(leaf, item, encryption); |
| btrfs_set_file_extent_other_encoding(leaf, item, other_encoding); |
| |
| btrfs_mark_buffer_dirty(leaf); |
| out: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| u64 objectid, u64 offset, |
| int cow) |
| { |
| int ret; |
| struct btrfs_key file_key; |
| struct btrfs_key found_key; |
| struct btrfs_csum_item *item; |
| struct extent_buffer *leaf; |
| u64 csum_offset = 0; |
| u16 csum_size = |
| btrfs_super_csum_size(&root->fs_info->super_copy); |
| int csums_in_item; |
| |
| file_key.objectid = objectid; |
| file_key.offset = offset; |
| btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY); |
| ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow); |
| if (ret < 0) |
| goto fail; |
| leaf = path->nodes[0]; |
| if (ret > 0) { |
| ret = 1; |
| if (path->slots[0] == 0) |
| goto fail; |
| path->slots[0]--; |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY || |
| found_key.objectid != objectid) { |
| goto fail; |
| } |
| csum_offset = (offset - found_key.offset) >> |
| root->fs_info->sb->s_blocksize_bits; |
| csums_in_item = btrfs_item_size_nr(leaf, path->slots[0]); |
| csums_in_item /= csum_size; |
| |
| if (csum_offset >= csums_in_item) { |
| ret = -EFBIG; |
| goto fail; |
| } |
| } |
| item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item); |
| item = (struct btrfs_csum_item *)((unsigned char *)item + |
| csum_offset * csum_size); |
| return item; |
| fail: |
| if (ret > 0) |
| ret = -ENOENT; |
| return ERR_PTR(ret); |
| } |
| |
| |
| int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, u64 objectid, |
| u64 offset, int mod) |
| { |
| int ret; |
| struct btrfs_key file_key; |
| int ins_len = mod < 0 ? -1 : 0; |
| int cow = mod != 0; |
| |
| file_key.objectid = objectid; |
| file_key.offset = offset; |
| btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY); |
| ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow); |
| return ret; |
| } |
| |
| int btrfs_lookup_bio_sums(struct btrfs_root *root, struct inode *inode, |
| struct bio *bio) |
| { |
| u32 sum; |
| struct bio_vec *bvec = bio->bi_io_vec; |
| int bio_index = 0; |
| u64 offset; |
| u64 item_start_offset = 0; |
| u64 item_last_offset = 0; |
| u32 diff; |
| u16 csum_size = |
| btrfs_super_csum_size(&root->fs_info->super_copy); |
| int ret; |
| struct btrfs_path *path; |
| struct btrfs_csum_item *item = NULL; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| |
| path = btrfs_alloc_path(); |
| if (bio->bi_size > PAGE_CACHE_SIZE * 8) |
| path->reada = 2; |
| |
| WARN_ON(bio->bi_vcnt <= 0); |
| |
| while(bio_index < bio->bi_vcnt) { |
| offset = page_offset(bvec->bv_page) + bvec->bv_offset; |
| ret = btrfs_find_ordered_sum(inode, offset, &sum); |
| if (ret == 0) |
| goto found; |
| |
| if (!item || offset < item_start_offset || |
| offset >= item_last_offset) { |
| struct btrfs_key found_key; |
| u32 item_size; |
| |
| if (item) |
| btrfs_release_path(root, path); |
| item = btrfs_lookup_csum(NULL, root, path, |
| inode->i_ino, offset, 0); |
| if (IS_ERR(item)) { |
| ret = PTR_ERR(item); |
| if (ret == -ENOENT || ret == -EFBIG) |
| ret = 0; |
| sum = 0; |
| printk("no csum found for inode %lu start " |
| "%llu\n", inode->i_ino, |
| (unsigned long long)offset); |
| item = NULL; |
| btrfs_release_path(root, path); |
| goto found; |
| } |
| btrfs_item_key_to_cpu(path->nodes[0], &found_key, |
| path->slots[0]); |
| |
| item_start_offset = found_key.offset; |
| item_size = btrfs_item_size_nr(path->nodes[0], |
| path->slots[0]); |
| item_last_offset = item_start_offset + |
| (item_size / csum_size) * |
| root->sectorsize; |
| item = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| struct btrfs_csum_item); |
| } |
| /* |
| * this byte range must be able to fit inside |
| * a single leaf so it will also fit inside a u32 |
| */ |
| diff = offset - item_start_offset; |
| diff = diff / root->sectorsize; |
| diff = diff * csum_size; |
| |
| read_extent_buffer(path->nodes[0], &sum, |
| ((unsigned long)item) + diff, |
| csum_size); |
| found: |
| set_state_private(io_tree, offset, sum); |
| bio_index++; |
| bvec++; |
| } |
| btrfs_free_path(path); |
| return 0; |
| } |
| |
| int btrfs_csum_file_bytes(struct btrfs_root *root, struct inode *inode, |
| u64 start, unsigned long len) |
| { |
| struct btrfs_ordered_sum *sums; |
| struct btrfs_sector_sum *sector_sum; |
| struct btrfs_ordered_extent *ordered; |
| char *data; |
| struct page *page; |
| unsigned long total_bytes = 0; |
| unsigned long this_sum_bytes = 0; |
| |
| sums = kzalloc(btrfs_ordered_sum_size(root, len), GFP_NOFS); |
| if (!sums) |
| return -ENOMEM; |
| |
| sector_sum = sums->sums; |
| sums->file_offset = start; |
| sums->len = len; |
| INIT_LIST_HEAD(&sums->list); |
| ordered = btrfs_lookup_ordered_extent(inode, sums->file_offset); |
| BUG_ON(!ordered); |
| |
| while(len > 0) { |
| if (start >= ordered->file_offset + ordered->len || |
| start < ordered->file_offset) { |
| sums->len = this_sum_bytes; |
| this_sum_bytes = 0; |
| btrfs_add_ordered_sum(inode, ordered, sums); |
| btrfs_put_ordered_extent(ordered); |
| |
| sums = kzalloc(btrfs_ordered_sum_size(root, len), |
| GFP_NOFS); |
| BUG_ON(!sums); |
| sector_sum = sums->sums; |
| sums->len = len; |
| sums->file_offset = start; |
| ordered = btrfs_lookup_ordered_extent(inode, |
| sums->file_offset); |
| BUG_ON(!ordered); |
| } |
| |
| page = find_get_page(inode->i_mapping, |
| start >> PAGE_CACHE_SHIFT); |
| |
| data = kmap_atomic(page, KM_USER0); |
| sector_sum->sum = ~(u32)0; |
| sector_sum->sum = btrfs_csum_data(root, data, sector_sum->sum, |
| PAGE_CACHE_SIZE); |
| kunmap_atomic(data, KM_USER0); |
| btrfs_csum_final(sector_sum->sum, |
| (char *)§or_sum->sum); |
| sector_sum->offset = page_offset(page); |
| page_cache_release(page); |
| |
| sector_sum++; |
| total_bytes += PAGE_CACHE_SIZE; |
| this_sum_bytes += PAGE_CACHE_SIZE; |
| start += PAGE_CACHE_SIZE; |
| |
| WARN_ON(len < PAGE_CACHE_SIZE); |
| len -= PAGE_CACHE_SIZE; |
| } |
| btrfs_add_ordered_sum(inode, ordered, sums); |
| btrfs_put_ordered_extent(ordered); |
| return 0; |
| } |
| |
| int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode, |
| struct bio *bio) |
| { |
| struct btrfs_ordered_sum *sums; |
| struct btrfs_sector_sum *sector_sum; |
| struct btrfs_ordered_extent *ordered; |
| char *data; |
| struct bio_vec *bvec = bio->bi_io_vec; |
| int bio_index = 0; |
| unsigned long total_bytes = 0; |
| unsigned long this_sum_bytes = 0; |
| u64 offset; |
| |
| WARN_ON(bio->bi_vcnt <= 0); |
| sums = kzalloc(btrfs_ordered_sum_size(root, bio->bi_size), GFP_NOFS); |
| if (!sums) |
| return -ENOMEM; |
| |
| sector_sum = sums->sums; |
| sums->file_offset = page_offset(bvec->bv_page) + bvec->bv_offset; |
| sums->len = bio->bi_size; |
| INIT_LIST_HEAD(&sums->list); |
| ordered = btrfs_lookup_ordered_extent(inode, sums->file_offset); |
| BUG_ON(!ordered); |
| |
| while(bio_index < bio->bi_vcnt) { |
| offset = page_offset(bvec->bv_page) + bvec->bv_offset; |
| if (offset >= ordered->file_offset + ordered->len || |
| offset < ordered->file_offset) { |
| unsigned long bytes_left; |
| sums->len = this_sum_bytes; |
| this_sum_bytes = 0; |
| btrfs_add_ordered_sum(inode, ordered, sums); |
| btrfs_put_ordered_extent(ordered); |
| |
| bytes_left = bio->bi_size - total_bytes; |
| |
| sums = kzalloc(btrfs_ordered_sum_size(root, bytes_left), |
| GFP_NOFS); |
| BUG_ON(!sums); |
| sector_sum = sums->sums; |
| sums->len = bytes_left; |
| sums->file_offset = offset; |
| ordered = btrfs_lookup_ordered_extent(inode, |
| sums->file_offset); |
| BUG_ON(!ordered); |
| } |
| |
| data = kmap_atomic(bvec->bv_page, KM_USER0); |
| sector_sum->sum = ~(u32)0; |
| sector_sum->sum = btrfs_csum_data(root, |
| data + bvec->bv_offset, |
| sector_sum->sum, |
| bvec->bv_len); |
| kunmap_atomic(data, KM_USER0); |
| btrfs_csum_final(sector_sum->sum, |
| (char *)§or_sum->sum); |
| sector_sum->offset = page_offset(bvec->bv_page) + |
| bvec->bv_offset; |
| |
| sector_sum++; |
| bio_index++; |
| total_bytes += bvec->bv_len; |
| this_sum_bytes += bvec->bv_len; |
| bvec++; |
| } |
| this_sum_bytes = 0; |
| btrfs_add_ordered_sum(inode, ordered, sums); |
| btrfs_put_ordered_extent(ordered); |
| return 0; |
| } |
| |
| int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode, |
| struct btrfs_ordered_sum *sums) |
| { |
| u64 objectid = inode->i_ino; |
| u64 offset; |
| int ret; |
| struct btrfs_key file_key; |
| struct btrfs_key found_key; |
| u64 next_offset; |
| u64 total_bytes = 0; |
| int found_next; |
| struct btrfs_path *path; |
| struct btrfs_csum_item *item; |
| struct btrfs_csum_item *item_end; |
| struct extent_buffer *leaf = NULL; |
| u64 csum_offset; |
| struct btrfs_sector_sum *sector_sum; |
| u32 nritems; |
| u32 ins_size; |
| char *eb_map; |
| char *eb_token; |
| unsigned long map_len; |
| unsigned long map_start; |
| u16 csum_size = |
| btrfs_super_csum_size(&root->fs_info->super_copy); |
| |
| path = btrfs_alloc_path(); |
| BUG_ON(!path); |
| sector_sum = sums->sums; |
| again: |
| next_offset = (u64)-1; |
| found_next = 0; |
| offset = sector_sum->offset; |
| file_key.objectid = objectid; |
| file_key.offset = offset; |
| btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY); |
| |
| mutex_lock(&BTRFS_I(inode)->csum_mutex); |
| item = btrfs_lookup_csum(trans, root, path, objectid, offset, 1); |
| if (!IS_ERR(item)) { |
| leaf = path->nodes[0]; |
| ret = 0; |
| goto found; |
| } |
| ret = PTR_ERR(item); |
| if (ret == -EFBIG) { |
| u32 item_size; |
| /* we found one, but it isn't big enough yet */ |
| leaf = path->nodes[0]; |
| item_size = btrfs_item_size_nr(leaf, path->slots[0]); |
| if ((item_size / csum_size) >= |
| MAX_CSUM_ITEMS(root, csum_size)) { |
| /* already at max size, make a new one */ |
| goto insert; |
| } |
| } else { |
| int slot = path->slots[0] + 1; |
| /* we didn't find a csum item, insert one */ |
| nritems = btrfs_header_nritems(path->nodes[0]); |
| if (path->slots[0] >= nritems - 1) { |
| ret = btrfs_next_leaf(root, path); |
| if (ret == 1) |
| found_next = 1; |
| if (ret != 0) |
| goto insert; |
| slot = 0; |
| } |
| btrfs_item_key_to_cpu(path->nodes[0], &found_key, slot); |
| if (found_key.objectid != objectid || |
| found_key.type != BTRFS_CSUM_ITEM_KEY) { |
| found_next = 1; |
| goto insert; |
| } |
| next_offset = found_key.offset; |
| found_next = 1; |
| goto insert; |
| } |
| |
| /* |
| * at this point, we know the tree has an item, but it isn't big |
| * enough yet to put our csum in. Grow it |
| */ |
| btrfs_release_path(root, path); |
| ret = btrfs_search_slot(trans, root, &file_key, path, |
| csum_size, 1); |
| if (ret < 0) |
| goto fail_unlock; |
| if (ret == 0) { |
| BUG(); |
| } |
| if (path->slots[0] == 0) { |
| goto insert; |
| } |
| path->slots[0]--; |
| leaf = path->nodes[0]; |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| csum_offset = (offset - found_key.offset) >> |
| root->fs_info->sb->s_blocksize_bits; |
| if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY || |
| found_key.objectid != objectid || |
| csum_offset >= MAX_CSUM_ITEMS(root, csum_size)) { |
| goto insert; |
| } |
| if (csum_offset >= btrfs_item_size_nr(leaf, path->slots[0]) / |
| csum_size) { |
| u32 diff = (csum_offset + 1) * csum_size; |
| diff = diff - btrfs_item_size_nr(leaf, path->slots[0]); |
| if (diff != csum_size) |
| goto insert; |
| ret = btrfs_extend_item(trans, root, path, diff); |
| BUG_ON(ret); |
| goto csum; |
| } |
| |
| insert: |
| btrfs_release_path(root, path); |
| csum_offset = 0; |
| if (found_next) { |
| u64 tmp = min((u64)i_size_read(inode), next_offset); |
| tmp -= offset & ~((u64)root->sectorsize -1); |
| tmp >>= root->fs_info->sb->s_blocksize_bits; |
| tmp = max((u64)1, tmp); |
| tmp = min(tmp, (u64)MAX_CSUM_ITEMS(root, csum_size)); |
| ins_size = csum_size * tmp; |
| } else { |
| ins_size = csum_size; |
| } |
| ret = btrfs_insert_empty_item(trans, root, path, &file_key, |
| ins_size); |
| if (ret < 0) |
| goto fail_unlock; |
| if (ret != 0) { |
| WARN_ON(1); |
| goto fail_unlock; |
| } |
| csum: |
| leaf = path->nodes[0]; |
| item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item); |
| ret = 0; |
| item = (struct btrfs_csum_item *)((unsigned char *)item + |
| csum_offset * csum_size); |
| found: |
| item_end = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item); |
| item_end = (struct btrfs_csum_item *)((unsigned char *)item_end + |
| btrfs_item_size_nr(leaf, path->slots[0])); |
| eb_token = NULL; |
| mutex_unlock(&BTRFS_I(inode)->csum_mutex); |
| cond_resched(); |
| next_sector: |
| |
| if (!eb_token || |
| (unsigned long)item + csum_size >= map_start + map_len) { |
| int err; |
| |
| if (eb_token) |
| unmap_extent_buffer(leaf, eb_token, KM_USER1); |
| eb_token = NULL; |
| err = map_private_extent_buffer(leaf, (unsigned long)item, |
| csum_size, |
| &eb_token, &eb_map, |
| &map_start, &map_len, KM_USER1); |
| if (err) |
| eb_token = NULL; |
| } |
| if (eb_token) { |
| memcpy(eb_token + ((unsigned long)item & (PAGE_CACHE_SIZE - 1)), |
| §or_sum->sum, csum_size); |
| } else { |
| write_extent_buffer(leaf, §or_sum->sum, |
| (unsigned long)item, csum_size); |
| } |
| |
| total_bytes += root->sectorsize; |
| sector_sum++; |
| if (total_bytes < sums->len) { |
| item = (struct btrfs_csum_item *)((char *)item + |
| csum_size); |
| if (item < item_end && offset + PAGE_CACHE_SIZE == |
| sector_sum->offset) { |
| offset = sector_sum->offset; |
| goto next_sector; |
| } |
| } |
| if (eb_token) { |
| unmap_extent_buffer(leaf, eb_token, KM_USER1); |
| eb_token = NULL; |
| } |
| btrfs_mark_buffer_dirty(path->nodes[0]); |
| cond_resched(); |
| if (total_bytes < sums->len) { |
| btrfs_release_path(root, path); |
| goto again; |
| } |
| out: |
| btrfs_free_path(path); |
| return ret; |
| |
| fail_unlock: |
| mutex_unlock(&BTRFS_I(inode)->csum_mutex); |
| goto out; |
| } |
| |
| int btrfs_csum_truncate(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct btrfs_path *path, |
| u64 isize) |
| { |
| struct btrfs_key key; |
| struct extent_buffer *leaf = path->nodes[0]; |
| int slot = path->slots[0]; |
| int ret; |
| u32 new_item_size; |
| u64 new_item_span; |
| u64 blocks; |
| |
| btrfs_item_key_to_cpu(leaf, &key, slot); |
| if (isize <= key.offset) |
| return 0; |
| new_item_span = isize - key.offset; |
| blocks = (new_item_span + root->sectorsize - 1) >> |
| root->fs_info->sb->s_blocksize_bits; |
| new_item_size = blocks * |
| btrfs_super_csum_size(&root->fs_info->super_copy); |
| if (new_item_size >= btrfs_item_size_nr(leaf, slot)) |
| return 0; |
| ret = btrfs_truncate_item(trans, root, path, new_item_size, 1); |
| BUG_ON(ret); |
| return ret; |
| } |