#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
+#include "print-tree.h"
#define MAX_CSUM_ITEMS(r) ((((BTRFS_LEAF_DATA_SIZE(r) - \
- sizeof(struct btrfs_item)) / \
- sizeof(struct btrfs_csum_item)) - 1))
-int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans,
+ sizeof(struct btrfs_item) * 2) / \
+ BTRFS_CRC32_SIZE) - 1))
+int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
- u64 objectid, u64 offset,
- u64 num_blocks, u64 hint_block,
- u64 *result)
+ u64 objectid, u64 pos,
+ u64 offset, u64 disk_num_blocks,
+ u64 num_blocks)
{
- struct btrfs_key ins;
int ret = 0;
struct btrfs_file_extent_item *item;
struct btrfs_key file_key;
path = btrfs_alloc_path();
BUG_ON(!path);
btrfs_init_path(path);
- ret = btrfs_alloc_extent(trans, root, num_blocks, hint_block,
- (u64)-1, &ins);
- BUG_ON(ret);
file_key.objectid = objectid;
- file_key.offset = offset;
+ file_key.offset = pos;
file_key.flags = 0;
btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
BUG_ON(ret);
item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
struct btrfs_file_extent_item);
- btrfs_set_file_extent_disk_blocknr(item, ins.objectid);
- btrfs_set_file_extent_disk_num_blocks(item, ins.offset);
+ btrfs_set_file_extent_disk_blocknr(item, offset);
+ btrfs_set_file_extent_disk_num_blocks(item, disk_num_blocks);
btrfs_set_file_extent_offset(item, 0);
- btrfs_set_file_extent_num_blocks(item, ins.offset);
+ btrfs_set_file_extent_num_blocks(item, num_blocks);
btrfs_set_file_extent_generation(item, trans->transid);
+ btrfs_set_file_extent_type(item, BTRFS_FILE_EXTENT_REG);
btrfs_mark_buffer_dirty(path->nodes[0]);
- *result = ins.objectid;
+
btrfs_release_path(root, path);
btrfs_free_path(path);
return 0;
}
-static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root,
- struct btrfs_path *path,
- u64 objectid, u64 offset)
+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_csum_item *item;
struct btrfs_leaf *leaf;
u64 csum_offset = 0;
+ int csums_in_item;
file_key.objectid = objectid;
file_key.offset = offset;
file_key.flags = 0;
btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
- ret = btrfs_search_slot(NULL, root, &file_key, path, 0, 0);
+ ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
if (ret < 0)
goto fail;
leaf = btrfs_buffer_leaf(path->nodes[0]);
}
csum_offset = (offset - found_key.offset) >>
root->fs_info->sb->s_blocksize_bits;
- if (csum_offset >=
- btrfs_item_size(leaf->items + path->slots[0]) /
- sizeof(struct btrfs_csum_item)) {
+ csums_in_item = btrfs_item_size(leaf->items + path->slots[0]);
+ csums_in_item /= BTRFS_CRC32_SIZE;
+
+ if (csum_offset >= csums_in_item) {
+ ret = -EFBIG;
goto fail;
}
}
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
- item += csum_offset;
+ item = (struct btrfs_csum_item *)((unsigned char *)item +
+ csum_offset * BTRFS_CRC32_SIZE);
return item;
fail:
if (ret > 0)
- ret = -EIO;
+ ret = -ENOENT;
return ERR_PTR(ret);
}
struct btrfs_key file_key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
- struct btrfs_csum_item *csum_item;
- csum_item = __lookup_csum_item(root, path, objectid, offset);
- if (IS_ERR(csum_item))
- return PTR_ERR(csum_item);
file_key.objectid = objectid;
- file_key.offset = btrfs_csum_extent_offset(csum_item);
+ file_key.offset = offset;
file_key.flags = 0;
btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
- btrfs_release_path(root, path);
ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
return ret;
}
int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 objectid, u64 offset,
- u64 extent_offset,
char *data, size_t len)
{
int ret;
path = btrfs_alloc_path();
BUG_ON(!path);
- btrfs_init_path(path);
+
file_key.objectid = objectid;
file_key.offset = offset;
file_key.flags = 0;
btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
+
+ item = btrfs_lookup_csum(trans, root, path, objectid, offset, 1);
+ if (!IS_ERR(item))
+ goto found;
+ ret = PTR_ERR(item);
+ if (ret == -EFBIG) {
+ u32 item_size;
+ /* we found one, but it isn't big enough yet */
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ item_size = btrfs_item_size(leaf->items + path->slots[0]);
+ if ((item_size / BTRFS_CRC32_SIZE) >= MAX_CSUM_ITEMS(root)) {
+ /* already at max size, make a new one */
+ goto insert;
+ }
+ } else {
+ /* we didn't find a csum item, insert one */
+ 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,
- sizeof(struct btrfs_csum_item), 1);
+ BTRFS_CRC32_SIZE, 1);
if (ret < 0)
goto fail;
if (ret == 0) {
- csum_offset = 0;
- goto csum;
+ BUG();
}
if (path->slots[0] == 0) {
- btrfs_release_path(root, path);
goto insert;
}
path->slots[0]--;
if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY ||
found_key.objectid != objectid ||
csum_offset >= MAX_CSUM_ITEMS(root)) {
- btrfs_release_path(root, path);
goto insert;
}
if (csum_offset >= btrfs_item_size(leaf->items + path->slots[0]) /
- sizeof(struct btrfs_csum_item)) {
- ret = btrfs_extend_item(trans, root, path,
- sizeof(struct btrfs_csum_item));
+ BTRFS_CRC32_SIZE) {
+ u32 diff = (csum_offset + 1) * BTRFS_CRC32_SIZE;
+ diff = diff - btrfs_item_size(leaf->items + path->slots[0]);
+ if (diff != BTRFS_CRC32_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;
ret = btrfs_insert_empty_item(trans, root, path, &file_key,
- sizeof(struct btrfs_csum_item));
- if (ret != 0 && ret != -EEXIST)
+ BTRFS_CRC32_SIZE);
+ if (ret != 0) {
+ WARN_ON(1);
goto fail;
+ }
csum:
item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
struct btrfs_csum_item);
ret = 0;
- item += csum_offset;
- ret = btrfs_csum_data(root, data, len, item->csum);
- btrfs_set_csum_extent_offset(item, extent_offset);
+ item = (struct btrfs_csum_item *)((unsigned char *)item +
+ csum_offset * BTRFS_CRC32_SIZE);
+found:
+ btrfs_check_bounds(&item->csum, BTRFS_CRC32_SIZE,
+ path->nodes[0]->b_data,
+ root->fs_info->sb->s_blocksize);
+ ret = btrfs_csum_data(root, data, len, &item->csum);
btrfs_mark_buffer_dirty(path->nodes[0]);
fail:
btrfs_release_path(root, path);
return ret;
}
+int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct btrfs_path *path,
+ u64 isize)
+{
+ struct btrfs_key key;
+ struct btrfs_leaf *leaf = btrfs_buffer_leaf(path->nodes[0]);
+ int slot = path->slots[0];
+ int ret;
+ u32 new_item_size;
+ u64 new_item_span;
+ u64 blocks;
+
+ btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
+ if (isize <= key.offset)
+ return 0;
+ new_item_span = isize - key.offset;
+ blocks = (new_item_span + root->blocksize - 1) >>
+ root->fs_info->sb->s_blocksize_bits;
+ new_item_size = blocks * BTRFS_CRC32_SIZE;
+ if (new_item_size >= btrfs_item_size(leaf->items + slot))
+ return 0;
+ ret = btrfs_truncate_item(trans, root, path, new_item_size);
+ BUG_ON(ret);
+ return ret;
+}
+
int btrfs_csum_verify_file_block(struct btrfs_root *root,
u64 objectid, u64 offset,
char *data, size_t len)
struct btrfs_key file_key;
struct btrfs_path *path;
struct btrfs_csum_item *item;
- char result[BTRFS_CSUM_SIZE];
+ char result[BTRFS_CRC32_SIZE];
path = btrfs_alloc_path();
BUG_ON(!path);
btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
mutex_lock(&root->fs_info->fs_mutex);
- item = __lookup_csum_item(root, path, objectid, offset);
+ item = btrfs_lookup_csum(NULL, root, path, objectid, offset, 0);
if (IS_ERR(item)) {
ret = PTR_ERR(item);
+ /* a csum that isn't present is a preallocated region. */
+ if (ret == -ENOENT || ret == -EFBIG)
+ ret = -ENOENT;
goto fail;
}
ret = btrfs_csum_data(root, data, len, result);
WARN_ON(ret);
- if (memcmp(result, item->csum, BTRFS_CSUM_SIZE))
+ if (memcmp(result, &item->csum, BTRFS_CRC32_SIZE))
ret = 1;
fail:
btrfs_release_path(root, path);