diff options
Diffstat (limited to 'volumes.c')
| -rw-r--r-- | volumes.c | 104 |
1 files changed, 98 insertions, 6 deletions
@@ -272,7 +272,7 @@ static int find_free_dev_extent(struct btrfs_trans_handle *trans, struct btrfs_dev_extent *dev_extent = NULL; u64 hole_size = 0; u64 last_byte = 0; - u64 search_start = 0; + u64 search_start = root->fs_info->alloc_start; u64 search_end = device->total_bytes; int ret; int slot = 0; @@ -287,10 +287,12 @@ static int find_free_dev_extent(struct btrfs_trans_handle *trans, /* we don't want to overwrite the superblock on the drive, * so we make sure to start at an offset of at least 1MB */ - search_start = max((u64)1024 * 1024, search_start); + search_start = max(BTRFS_BLOCK_RESERVED_1M_FOR_SUPER, search_start); - if (root->fs_info->alloc_start + num_bytes <= device->total_bytes) - search_start = max(root->fs_info->alloc_start, search_start); + if (search_start >= search_end) { + ret = -ENOSPC; + goto error; + } key.objectid = device->devid; key.offset = search_start; @@ -656,6 +658,94 @@ static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target) return 64 * 1024; } +/* + * btrfs_device_avail_bytes - count bytes available for alloc_chunk + * + * It is not equal to "device->total_bytes - device->bytes_used". + * We do not allocate any chunk in 1M at beginning of device, and not + * allowed to allocate any chunk before alloc_start if it is specified. + * So search holes from max(1M, alloc_start) to device->total_bytes. + */ +static int btrfs_device_avail_bytes(struct btrfs_trans_handle *trans, + struct btrfs_device *device, + u64 *avail_bytes) +{ + struct btrfs_path *path; + struct btrfs_root *root = device->dev_root; + struct btrfs_key key; + struct btrfs_dev_extent *dev_extent = NULL; + struct extent_buffer *l; + u64 search_start = root->fs_info->alloc_start; + u64 search_end = device->total_bytes; + u64 extent_end = 0; + u64 free_bytes = 0; + int ret; + int slot = 0; + + search_start = max(BTRFS_BLOCK_RESERVED_1M_FOR_SUPER, search_start); + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = device->devid; + key.offset = root->fs_info->alloc_start; + key.type = BTRFS_DEV_EXTENT_KEY; + + path->reada = 2; + ret = btrfs_search_slot(trans, root, &key, path, 0, 0); + if (ret < 0) + goto error; + ret = btrfs_previous_item(root, path, 0, key.type); + if (ret < 0) + goto error; + + while (1) { + l = path->nodes[0]; + slot = path->slots[0]; + if (slot >= btrfs_header_nritems(l)) { + ret = btrfs_next_leaf(root, path); + if (ret == 0) + continue; + if (ret < 0) + goto error; + break; + } + btrfs_item_key_to_cpu(l, &key, slot); + + if (key.objectid < device->devid) + goto next; + if (key.objectid > device->devid) + break; + if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) + goto next; + if (key.offset > search_end) + break; + if (key.offset > search_start) + free_bytes += key.offset - search_start; + + dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); + extent_end = key.offset + btrfs_dev_extent_length(l, + dev_extent); + if (extent_end > search_start) + search_start = extent_end; + if (search_start > search_end) + break; +next: + path->slots[0]++; + cond_resched(); + } + + if (search_start < search_end) + free_bytes += search_end - search_start; + + *avail_bytes = free_bytes; + ret = 0; +error: + btrfs_free_path(path); + return ret; +} + int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root, u64 *start, u64 *num_bytes, u64 type) @@ -674,7 +764,7 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 calc_size = 8 * 1024 * 1024; u64 min_free; u64 max_chunk_size = 4 * calc_size; - u64 avail; + u64 avail = 0; u64 max_avail = 0; u64 percent_max; int num_stripes = 1; @@ -778,7 +868,9 @@ again: /* build a private list of devices we will allocate from */ while(index < num_stripes) { device = list_entry(cur, struct btrfs_device, dev_list); - avail = device->total_bytes - device->bytes_used; + ret = btrfs_device_avail_bytes(trans, device, &avail); + if (ret) + return ret; cur = cur->next; if (avail >= min_free) { list_move_tail(&device->dev_list, &private_devs); |