diff options
Diffstat (limited to 'volumes.c')
| -rw-r--r-- | volumes.c | 2172 |
1 files changed, 2172 insertions, 0 deletions
diff --git a/volumes.c b/volumes.c new file mode 100644 index 00000000..ccfa732e --- /dev/null +++ b/volumes.c @@ -0,0 +1,2172 @@ +/* + * 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 <stdio.h> +#include <stdlib.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <uuid/uuid.h> +#include <fcntl.h> +#include <unistd.h> +#include "ctree.h" +#include "disk-io.h" +#include "transaction.h" +#include "print-tree.h" +#include "volumes.h" +#include "utils.h" + +struct stripe { + struct btrfs_device *dev; + u64 physical; +}; + +static inline int nr_parity_stripes(struct map_lookup *map) +{ + if (map->type & BTRFS_BLOCK_GROUP_RAID5) + return 1; + else if (map->type & BTRFS_BLOCK_GROUP_RAID6) + return 2; + else + return 0; +} + +static inline int nr_data_stripes(struct map_lookup *map) +{ + return map->num_stripes - nr_parity_stripes(map); +} + +#define is_parity_stripe(x) ( ((x) == BTRFS_RAID5_P_STRIPE) || ((x) == BTRFS_RAID6_Q_STRIPE) ) + +static LIST_HEAD(fs_uuids); + +static struct btrfs_device *__find_device(struct list_head *head, u64 devid, + u8 *uuid) +{ + struct btrfs_device *dev; + struct list_head *cur; + + list_for_each(cur, head) { + dev = list_entry(cur, struct btrfs_device, dev_list); + if (dev->devid == devid && + !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE)) { + return dev; + } + } + return NULL; +} + +static struct btrfs_fs_devices *find_fsid(u8 *fsid) +{ + struct list_head *cur; + struct btrfs_fs_devices *fs_devices; + + list_for_each(cur, &fs_uuids) { + fs_devices = list_entry(cur, struct btrfs_fs_devices, list); + if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) + return fs_devices; + } + return NULL; +} + +static int device_list_add(const char *path, + struct btrfs_super_block *disk_super, + u64 devid, struct btrfs_fs_devices **fs_devices_ret) +{ + struct btrfs_device *device; + struct btrfs_fs_devices *fs_devices; + u64 found_transid = btrfs_super_generation(disk_super); + + fs_devices = find_fsid(disk_super->fsid); + if (!fs_devices) { + fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); + if (!fs_devices) + return -ENOMEM; + INIT_LIST_HEAD(&fs_devices->devices); + list_add(&fs_devices->list, &fs_uuids); + memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE); + fs_devices->latest_devid = devid; + fs_devices->latest_trans = found_transid; + fs_devices->lowest_devid = (u64)-1; + device = NULL; + } else { + device = __find_device(&fs_devices->devices, devid, + disk_super->dev_item.uuid); + } + if (!device) { + device = kzalloc(sizeof(*device), GFP_NOFS); + if (!device) { + /* we can safely leave the fs_devices entry around */ + return -ENOMEM; + } + device->fd = -1; + device->devid = devid; + device->generation = found_transid; + memcpy(device->uuid, disk_super->dev_item.uuid, + BTRFS_UUID_SIZE); + device->name = kstrdup(path, GFP_NOFS); + if (!device->name) { + kfree(device); + return -ENOMEM; + } + device->label = kstrdup(disk_super->label, GFP_NOFS); + if (!device->label) { + kfree(device->name); + kfree(device); + return -ENOMEM; + } + device->total_devs = btrfs_super_num_devices(disk_super); + device->super_bytes_used = btrfs_super_bytes_used(disk_super); + device->total_bytes = + btrfs_stack_device_total_bytes(&disk_super->dev_item); + device->bytes_used = + btrfs_stack_device_bytes_used(&disk_super->dev_item); + list_add(&device->dev_list, &fs_devices->devices); + device->fs_devices = fs_devices; + } else if (!device->name || strcmp(device->name, path)) { + char *name = strdup(path); + if (!name) + return -ENOMEM; + kfree(device->name); + device->name = name; + } + + + if (found_transid > fs_devices->latest_trans) { + fs_devices->latest_devid = devid; + fs_devices->latest_trans = found_transid; + } + if (fs_devices->lowest_devid > devid) { + fs_devices->lowest_devid = devid; + } + *fs_devices_ret = fs_devices; + return 0; +} + +int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) +{ + struct btrfs_fs_devices *seed_devices; + struct btrfs_device *device; + +again: + while (!list_empty(&fs_devices->devices)) { + device = list_entry(fs_devices->devices.next, + struct btrfs_device, dev_list); + if (device->fd != -1) { + fsync(device->fd); + if (posix_fadvise(device->fd, 0, 0, POSIX_FADV_DONTNEED)) + fprintf(stderr, "Warning, could not drop caches\n"); + close(device->fd); + device->fd = -1; + } + device->writeable = 0; + list_del(&device->dev_list); + /* free the memory */ + free(device->name); + free(device->label); + free(device); + } + + seed_devices = fs_devices->seed; + fs_devices->seed = NULL; + if (seed_devices) { + struct btrfs_fs_devices *orig; + + orig = fs_devices; + fs_devices = seed_devices; + list_del(&orig->list); + free(orig); + goto again; + } else { + list_del(&fs_devices->list); + free(fs_devices); + } + + return 0; +} + +void btrfs_close_all_devices(void) +{ + struct btrfs_fs_devices *fs_devices; + + while (!list_empty(&fs_uuids)) { + fs_devices = list_entry(fs_uuids.next, struct btrfs_fs_devices, + list); + btrfs_close_devices(fs_devices); + } +} + +int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, int flags) +{ + int fd; + struct list_head *head = &fs_devices->devices; + struct list_head *cur; + struct btrfs_device *device; + int ret; + + list_for_each(cur, head) { + device = list_entry(cur, struct btrfs_device, dev_list); + if (!device->name) { + printk("no name for device %llu, skip it now\n", device->devid); + continue; + } + + fd = open(device->name, flags); + if (fd < 0) { + ret = -errno; + goto fail; + } + + if (posix_fadvise(fd, 0, 0, POSIX_FADV_DONTNEED)) + fprintf(stderr, "Warning, could not drop caches\n"); + + if (device->devid == fs_devices->latest_devid) + fs_devices->latest_bdev = fd; + if (device->devid == fs_devices->lowest_devid) + fs_devices->lowest_bdev = fd; + device->fd = fd; + if (flags & O_RDWR) + device->writeable = 1; + } + return 0; +fail: + btrfs_close_devices(fs_devices); + return ret; +} + +int btrfs_scan_one_device(int fd, const char *path, + struct btrfs_fs_devices **fs_devices_ret, + u64 *total_devs, u64 super_offset, int super_recover) +{ + struct btrfs_super_block *disk_super; + char buf[BTRFS_SUPER_INFO_SIZE]; + int ret; + u64 devid; + + disk_super = (struct btrfs_super_block *)buf; + ret = btrfs_read_dev_super(fd, disk_super, super_offset, super_recover); + if (ret < 0) + return -EIO; + devid = btrfs_stack_device_id(&disk_super->dev_item); + if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_METADUMP) + *total_devs = 1; + else + *total_devs = btrfs_super_num_devices(disk_super); + + ret = device_list_add(path, disk_super, devid, fs_devices_ret); + + return ret; +} + +/* + * this uses a pretty simple search, the expectation is that it is + * called very infrequently and that a given device has a small number + * of extents + */ +static int find_free_dev_extent(struct btrfs_trans_handle *trans, + struct btrfs_device *device, + struct btrfs_path *path, + u64 num_bytes, u64 *start) +{ + struct btrfs_key key; + struct btrfs_root *root = device->dev_root; + struct btrfs_dev_extent *dev_extent = NULL; + u64 hole_size = 0; + u64 last_byte = 0; + u64 search_start = root->fs_info->alloc_start; + u64 search_end = device->total_bytes; + int ret; + int slot = 0; + int start_found; + struct extent_buffer *l; + + start_found = 0; + path->reada = 2; + + /* FIXME use last free of some kind */ + + /* 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(BTRFS_BLOCK_RESERVED_1M_FOR_SUPER, search_start); + + if (search_start >= search_end) { + ret = -ENOSPC; + goto error; + } + + key.objectid = device->devid; + key.offset = search_start; + key.type = BTRFS_DEV_EXTENT_KEY; + 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; + l = path->nodes[0]; + btrfs_item_key_to_cpu(l, &key, path->slots[0]); + 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; +no_more_items: + if (!start_found) { + if (search_start >= search_end) { + ret = -ENOSPC; + goto error; + } + *start = search_start; + start_found = 1; + goto check_pending; + } + *start = last_byte > search_start ? + last_byte : search_start; + if (search_end <= *start) { + ret = -ENOSPC; + goto error; + } + goto check_pending; + } + btrfs_item_key_to_cpu(l, &key, slot); + + if (key.objectid < device->devid) + goto next; + + if (key.objectid > device->devid) + goto no_more_items; + + if (key.offset >= search_start && key.offset > last_byte && + start_found) { + if (last_byte < search_start) + last_byte = search_start; + hole_size = key.offset - last_byte; + if (key.offset > last_byte && + hole_size >= num_bytes) { + *start = last_byte; + goto check_pending; + } + } + if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) { + goto next; + } + + start_found = 1; + dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); + last_byte = key.offset + btrfs_dev_extent_length(l, dev_extent); +next: + path->slots[0]++; + cond_resched(); + } +check_pending: + /* we have to make sure we didn't find an extent that has already + * been allocated by the map tree or the original allocation + */ + btrfs_release_path(path); + BUG_ON(*start < search_start); + + if (*start + num_bytes > search_end) { + ret = -ENOSPC; + goto error; + } + /* check for pending inserts here */ + return 0; + +error: + btrfs_release_path(path); + return ret; +} + +static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, + struct btrfs_device *device, + u64 chunk_tree, u64 chunk_objectid, + u64 chunk_offset, + u64 num_bytes, u64 *start, int convert) +{ + int ret; + struct btrfs_path *path; + struct btrfs_root *root = device->dev_root; + struct btrfs_dev_extent *extent; + struct extent_buffer *leaf; + struct btrfs_key key; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + /* + * For convert case, just skip search free dev_extent, as caller + * is responsible to make sure it's free. + */ + if (!convert) { + ret = find_free_dev_extent(trans, device, path, num_bytes, + start); + if (ret) + goto err; + } + + key.objectid = device->devid; + key.offset = *start; + key.type = BTRFS_DEV_EXTENT_KEY; + ret = btrfs_insert_empty_item(trans, root, path, &key, + sizeof(*extent)); + BUG_ON(ret); + + leaf = path->nodes[0]; + extent = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_dev_extent); + btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree); + btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid); + btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); + + write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, + (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent), + BTRFS_UUID_SIZE); + + btrfs_set_dev_extent_length(leaf, extent, num_bytes); + btrfs_mark_buffer_dirty(leaf); +err: + btrfs_free_path(path); + return ret; +} + +static int find_next_chunk(struct btrfs_root *root, u64 objectid, u64 *offset) +{ + struct btrfs_path *path; + int ret; + struct btrfs_key key; + struct btrfs_chunk *chunk; + struct btrfs_key found_key; + + path = btrfs_alloc_path(); + BUG_ON(!path); + + key.objectid = objectid; + key.offset = (u64)-1; + key.type = BTRFS_CHUNK_ITEM_KEY; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto error; + + BUG_ON(ret == 0); + + ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY); + if (ret) { + *offset = 0; + } else { + btrfs_item_key_to_cpu(path->nodes[0], &found_key, + path->slots[0]); + if (found_key.objectid != objectid) + *offset = 0; + else { + chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_chunk); + *offset = found_key.offset + + btrfs_chunk_length(path->nodes[0], chunk); + } + } + ret = 0; +error: + btrfs_free_path(path); + return ret; +} + +static int find_next_devid(struct btrfs_root *root, struct btrfs_path *path, + u64 *objectid) +{ + int ret; + struct btrfs_key key; + struct btrfs_key found_key; + + key.objectid = BTRFS_DEV_ITEMS_OBJECTID; + key.type = BTRFS_DEV_ITEM_KEY; + key.offset = (u64)-1; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto error; + + BUG_ON(ret == 0); + + ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID, + BTRFS_DEV_ITEM_KEY); + if (ret) { + *objectid = 1; + } else { + btrfs_item_key_to_cpu(path->nodes[0], &found_key, + path->slots[0]); + *objectid = found_key.offset + 1; + } + ret = 0; +error: + btrfs_release_path(path); + return ret; +} + +/* + * the device information is stored in the chunk root + * the btrfs_device struct should be fully filled in + */ +int btrfs_add_device(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_device *device) +{ + int ret; + struct btrfs_path *path; + struct btrfs_dev_item *dev_item; + struct extent_buffer *leaf; + struct btrfs_key key; + unsigned long ptr; + u64 free_devid = 0; + + root = root->fs_info->chunk_root; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + ret = find_next_devid(root, path, &free_devid); + if (ret) + goto out; + + key.objectid = BTRFS_DEV_ITEMS_OBJECTID; + key.type = BTRFS_DEV_ITEM_KEY; + key.offset = free_devid; + + ret = btrfs_insert_empty_item(trans, root, path, &key, + sizeof(*dev_item)); + if (ret) + goto out; + + leaf = path->nodes[0]; + dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); + + device->devid = free_devid; + btrfs_set_device_id(leaf, dev_item, device->devid); + btrfs_set_device_generation(leaf, dev_item, 0); + btrfs_set_device_type(leaf, dev_item, device->type); + btrfs_set_device_io_align(leaf, dev_item, device->io_align); + btrfs_set_device_io_width(leaf, dev_item, device->io_width); + btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); + btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); + btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); + btrfs_set_device_group(leaf, dev_item, 0); + btrfs_set_device_seek_speed(leaf, dev_item, 0); + btrfs_set_device_bandwidth(leaf, dev_item, 0); + btrfs_set_device_start_offset(leaf, dev_item, 0); + + ptr = (unsigned long)btrfs_device_uuid(dev_item); + write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); + ptr = (unsigned long)btrfs_device_fsid(dev_item); + write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE); + btrfs_mark_buffer_dirty(leaf); + ret = 0; + +out: + btrfs_free_path(path); + return ret; +} + +int btrfs_update_device(struct btrfs_trans_handle *trans, + struct btrfs_device *device) +{ + int ret; + struct btrfs_path *path; + struct btrfs_root *root; + struct btrfs_dev_item *dev_item; + struct extent_buffer *leaf; + struct btrfs_key key; + + root = device->dev_root->fs_info->chunk_root; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = BTRFS_DEV_ITEMS_OBJECTID; + key.type = BTRFS_DEV_ITEM_KEY; + key.offset = device->devid; + + ret = btrfs_search_slot(trans, root, &key, path, 0, 1); + if (ret < 0) + goto out; + + if (ret > 0) { + ret = -ENOENT; + goto out; + } + + leaf = path->nodes[0]; + dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); + + btrfs_set_device_id(leaf, dev_item, device->devid); + btrfs_set_device_type(leaf, dev_item, device->type); + btrfs_set_device_io_align(leaf, dev_item, device->io_align); + btrfs_set_device_io_width(leaf, dev_item, device->io_width); + btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); + btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); + btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); + btrfs_mark_buffer_dirty(leaf); + +out: + btrfs_free_path(path); + return ret; +} + +int btrfs_add_system_chunk(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_key *key, + struct btrfs_chunk *chunk, int item_size) +{ + struct btrfs_super_block *super_copy = root->fs_info->super_copy; + struct btrfs_disk_key disk_key; + u32 array_size; + u8 *ptr; + + array_size = btrfs_super_sys_array_size(super_copy); + if (array_size + item_size + sizeof(disk_key) + > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) + return -EFBIG; + + ptr = super_copy->sys_chunk_array + array_size; + btrfs_cpu_key_to_disk(&disk_key, key); + memcpy(ptr, &disk_key, sizeof(disk_key)); + ptr += sizeof(disk_key); + memcpy(ptr, chunk, item_size); + item_size += sizeof(disk_key); + btrfs_set_super_sys_array_size(super_copy, array_size + item_size); + return 0; +} + +static u64 chunk_bytes_by_type(u64 type, u64 calc_size, int num_stripes, + int sub_stripes) +{ + if (type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP)) + return calc_size; + else if (type & BTRFS_BLOCK_GROUP_RAID10) + return calc_size * (num_stripes / sub_stripes); + else if (type & BTRFS_BLOCK_GROUP_RAID5) + return calc_size * (num_stripes - 1); + else if (type & BTRFS_BLOCK_GROUP_RAID6) + return calc_size * (num_stripes - 2); + else + return calc_size * num_stripes; +} + + +static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target) +{ + /* TODO, add a way to store the preferred stripe size */ + return BTRFS_STRIPE_LEN; +} + +/* + * 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; +} + +#define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \ + - sizeof(struct btrfs_item) \ + - sizeof(struct btrfs_chunk)) \ + / sizeof(struct btrfs_stripe) + 1) + +#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \ + - 2 * sizeof(struct btrfs_disk_key) \ + - 2 * sizeof(struct btrfs_chunk)) \ + / sizeof(struct btrfs_stripe) + 1) + +int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, u64 *start, + u64 *num_bytes, u64 type) +{ + u64 dev_offset; + struct btrfs_fs_info *info = extent_root->fs_info; + struct btrfs_root *chunk_root = info->chunk_root; + struct btrfs_stripe *stripes; + struct btrfs_device *device = NULL; + struct btrfs_chunk *chunk; + struct list_head private_devs; + struct list_head *dev_list = &info->fs_devices->devices; + struct list_head *cur; + struct map_lookup *map; + int min_stripe_size = 1 * 1024 * 1024; + u64 calc_size = 8 * 1024 * 1024; + u64 min_free; + u64 max_chunk_size = 4 * calc_size; + u64 avail = 0; + u64 max_avail = 0; + u64 percent_max; + int num_stripes = 1; + int max_stripes = 0; + int min_stripes = 1; + int sub_stripes = 0; + int looped = 0; + int ret; + int index; + int stripe_len = BTRFS_STRIPE_LEN; + struct btrfs_key key; + u64 offset; + + if (list_empty(dev_list)) { + return -ENOSPC; + } + + if (type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | + BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 | + BTRFS_BLOCK_GROUP_RAID10 | + BTRFS_BLOCK_GROUP_DUP)) { + if (type & BTRFS_BLOCK_GROUP_SYSTEM) { + calc_size = 8 * 1024 * 1024; + max_chunk_size = calc_size * 2; + min_stripe_size = 1 * 1024 * 1024; + max_stripes = BTRFS_MAX_DEVS_SYS_CHUNK; + } else if (type & BTRFS_BLOCK_GROUP_DATA) { + calc_size = 1024 * 1024 * 1024; + max_chunk_size = 10 * calc_size; + min_stripe_size = 64 * 1024 * 1024; + max_stripes = BTRFS_MAX_DEVS(chunk_root); + } else if (type & BTRFS_BLOCK_GROUP_METADATA) { + calc_size = 1024 * 1024 * 1024; + max_chunk_size = 4 * calc_size; + min_stripe_size = 32 * 1024 * 1024; + max_stripes = BTRFS_MAX_DEVS(chunk_root); + } + } + if (type & BTRFS_BLOCK_GROUP_RAID1) { + num_stripes = min_t(u64, 2, + btrfs_super_num_devices(info->super_copy)); + if (num_stripes < 2) + return -ENOSPC; + min_stripes = 2; + } + if (type & BTRFS_BLOCK_GROUP_DUP) { + num_stripes = 2; + min_stripes = 2; + } + if (type & (BTRFS_BLOCK_GROUP_RAID0)) { + num_stripes = btrfs_super_num_devices(info->super_copy); + if (num_stripes > max_stripes) + num_stripes = max_stripes; + min_stripes = 2; + } + if (type & (BTRFS_BLOCK_GROUP_RAID10)) { + num_stripes = btrfs_super_num_devices(info->super_copy); + if (num_stripes > max_stripes) + num_stripes = max_stripes; + if (num_stripes < 4) + return -ENOSPC; + num_stripes &= ~(u32)1; + sub_stripes = 2; + min_stripes = 4; + } + if (type & (BTRFS_BLOCK_GROUP_RAID5)) { + num_stripes = btrfs_super_num_devices(info->super_copy); + if (num_stripes > max_stripes) + num_stripes = max_stripes; + if (num_stripes < 2) + return -ENOSPC; + min_stripes = 2; + stripe_len = find_raid56_stripe_len(num_stripes - 1, + btrfs_super_stripesize(info->super_copy)); + } + if (type & (BTRFS_BLOCK_GROUP_RAID6)) { + num_stripes = btrfs_super_num_devices(info->super_copy); + if (num_stripes > max_stripes) + num_stripes = max_stripes; + if (num_stripes < 3) + return -ENOSPC; + min_stripes = 3; + stripe_len = find_raid56_stripe_len(num_stripes - 2, + btrfs_super_stripesize(info->super_copy)); + } + + /* we don't want a chunk larger than 10% of the FS */ + percent_max = div_factor(btrfs_super_total_bytes(info->super_copy), 1); + max_chunk_size = min(percent_max, max_chunk_size); + +again: + if (chunk_bytes_by_type(type, calc_size, num_stripes, sub_stripes) > + max_chunk_size) { + calc_size = max_chunk_size; + calc_size /= num_stripes; + calc_size /= stripe_len; + calc_size *= stripe_len; + } + /* we don't want tiny stripes */ + calc_size = max_t(u64, calc_size, min_stripe_size); + + calc_size /= stripe_len; + calc_size *= stripe_len; + INIT_LIST_HEAD(&private_devs); + cur = dev_list->next; + index = 0; + + if (type & BTRFS_BLOCK_GROUP_DUP) + min_free = calc_size * 2; + else + min_free = calc_size; + + /* build a private list of devices we will allocate from */ + while(index < num_stripes) { + device = list_entry(cur, struct btrfs_device, dev_list); + 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); + index++; + if (type & BTRFS_BLOCK_GROUP_DUP) + index++; + } else if (avail > max_avail) + max_avail = avail; + if (cur == dev_list) + break; + } + if (index < num_stripes) { + list_splice(&private_devs, dev_list); + if (index >= min_stripes) { + num_stripes = index; + if (type & (BTRFS_BLOCK_GROUP_RAID10)) { + num_stripes /= sub_stripes; + num_stripes *= sub_stripes; + } + looped = 1; + goto again; + } + if (!looped && max_avail > 0) { + looped = 1; + calc_size = max_avail; + goto again; + } + return -ENOSPC; + } + ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, + &offset); + if (ret) + return ret; + key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; + key.type = BTRFS_CHUNK_ITEM_KEY; + key.offset = offset; + + chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS); + if (!chunk) + return -ENOMEM; + + map = kmalloc(btrfs_map_lookup_size(num_stripes), GFP_NOFS); + if (!map) { + kfree(chunk); + return -ENOMEM; + } + + stripes = &chunk->stripe; + *num_bytes = chunk_bytes_by_type(type, calc_size, + num_stripes, sub_stripes); + index = 0; + while(index < num_stripes) { + struct btrfs_stripe *stripe; + BUG_ON(list_empty(&private_devs)); + cur = private_devs.next; + device = list_entry(cur, struct btrfs_device, dev_list); + + /* loop over this device again if we're doing a dup group */ + if (!(type & BTRFS_BLOCK_GROUP_DUP) || + (index == num_stripes - 1)) + list_move_tail(&device->dev_list, dev_list); + + ret = btrfs_alloc_dev_extent(trans, device, + info->chunk_root->root_key.objectid, + BTRFS_FIRST_CHUNK_TREE_OBJECTID, key.offset, + calc_size, &dev_offset, 0); + BUG_ON(ret); + + device->bytes_used += calc_size; + ret = btrfs_update_device(trans, device); + BUG_ON(ret); + + map->stripes[index].dev = device; + map->stripes[index].physical = dev_offset; + stripe = stripes + index; + btrfs_set_stack_stripe_devid(stripe, device->devid); + btrfs_set_stack_stripe_offset(stripe, dev_offset); + memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); + index++; + } + BUG_ON(!list_empty(&private_devs)); + + /* key was set above */ + btrfs_set_stack_chunk_length(chunk, *num_bytes); + btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); + btrfs_set_stack_chunk_stripe_len(chunk, stripe_len); + btrfs_set_stack_chunk_type(chunk, type); + btrfs_set_stack_chunk_num_stripes(chunk, num_stripes); + btrfs_set_stack_chunk_io_align(chunk, stripe_len); + btrfs_set_stack_chunk_io_width(chunk, stripe_len); + btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); + btrfs_set_stack_chunk_sub_stripes(chunk, sub_stripes); + map->sector_size = extent_root->sectorsize; + map->stripe_len = stripe_len; + map->io_align = stripe_len; + map->io_width = stripe_len; + map->type = type; + map->num_stripes = num_stripes; + map->sub_stripes = sub_stripes; + + ret = btrfs_insert_item(trans, chunk_root, &key, chunk, + btrfs_chunk_item_size(num_stripes)); + BUG_ON(ret); + *start = key.offset;; + + map->ce.start = key.offset; + map->ce.size = *num_bytes; + + ret = insert_cache_extent(&info->mapping_tree.cache_tree, &map->ce); + BUG_ON(ret); + + if (type & BTRFS_BLOCK_GROUP_SYSTEM) { + ret = btrfs_add_system_chunk(trans, chunk_root, &key, + chunk, btrfs_chunk_item_size(num_stripes)); + BUG_ON(ret); + } + + kfree(chunk); + return ret; +} + +/* + * Alloc a DATA chunk with SINGLE profile. + * + * If 'convert' is set, it will alloc a chunk with 1:1 mapping + * (btrfs logical bytenr == on-disk bytenr) + * For that case, caller must make sure the chunk and dev_extent are not + * occupied. + */ +int btrfs_alloc_data_chunk(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, u64 *start, + u64 num_bytes, u64 type, int convert) +{ + u64 dev_offset; + struct btrfs_fs_info *info = extent_root->fs_info; + struct btrfs_root *chunk_root = info->chunk_root; + struct btrfs_stripe *stripes; + struct btrfs_device *device = NULL; + struct btrfs_chunk *chunk; + struct list_head *dev_list = &info->fs_devices->devices; + struct list_head *cur; + struct map_lookup *map; + u64 calc_size = 8 * 1024 * 1024; + int num_stripes = 1; + int sub_stripes = 0; + int ret; + int index; + int stripe_len = BTRFS_STRIPE_LEN; + struct btrfs_key key; + + key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; + key.type = BTRFS_CHUNK_ITEM_KEY; + if (convert) { + BUG_ON(*start != round_down(*start, extent_root->sectorsize)); + key.offset = *start; + dev_offset = *start; + } else { + ret = find_next_chunk(chunk_root, + BTRFS_FIRST_CHUNK_TREE_OBJECTID, + &key.offset); + if (ret) + return ret; + } + + chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS); + if (!chunk) + return -ENOMEM; + + map = kmalloc(btrfs_map_lookup_size(num_stripes), GFP_NOFS); + if (!map) { + kfree(chunk); + return -ENOMEM; + } + + stripes = &chunk->stripe; + calc_size = num_bytes; + + index = 0; + cur = dev_list->next; + device = list_entry(cur, struct btrfs_device, dev_list); + + while (index < num_stripes) { + struct btrfs_stripe *stripe; + + ret = btrfs_alloc_dev_extent(trans, device, + info->chunk_root->root_key.objectid, + BTRFS_FIRST_CHUNK_TREE_OBJECTID, key.offset, + calc_size, &dev_offset, convert); + BUG_ON(ret); + + device->bytes_used += calc_size; + ret = btrfs_update_device(trans, device); + BUG_ON(ret); + + map->stripes[index].dev = device; + map->stripes[index].physical = dev_offset; + stripe = stripes + index; + btrfs_set_stack_stripe_devid(stripe, device->devid); + btrfs_set_stack_stripe_offset(stripe, dev_offset); + memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); + index++; + } + + /* key was set above */ + btrfs_set_stack_chunk_length(chunk, num_bytes); + btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); + btrfs_set_stack_chunk_stripe_len(chunk, stripe_len); + btrfs_set_stack_chunk_type(chunk, type); + btrfs_set_stack_chunk_num_stripes(chunk, num_stripes); + btrfs_set_stack_chunk_io_align(chunk, stripe_len); + btrfs_set_stack_chunk_io_width(chunk, stripe_len); + btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); + btrfs_set_stack_chunk_sub_stripes(chunk, sub_stripes); + map->sector_size = extent_root->sectorsize; + map->stripe_len = stripe_len; + map->io_align = stripe_len; + map->io_width = stripe_len; + map->type = type; + map->num_stripes = num_stripes; + map->sub_stripes = sub_stripes; + + ret = btrfs_insert_item(trans, chunk_root, &key, chunk, + btrfs_chunk_item_size(num_stripes)); + BUG_ON(ret); + if (!convert) + *start = key.offset; + + map->ce.start = key.offset; + map->ce.size = num_bytes; + + ret = insert_cache_extent(&info->mapping_tree.cache_tree, &map->ce); + BUG_ON(ret); + + kfree(chunk); + return ret; +} + +int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len) +{ + struct cache_extent *ce; + struct map_lookup *map; + int ret; + + ce = search_cache_extent(&map_tree->cache_tree, logical); + if (!ce) { + fprintf(stderr, "No mapping for %llu-%llu\n", + (unsigned long long)logical, + (unsigned long long)logical+len); + return 1; + } + if (ce->start > logical || ce->start + ce->size < logical) { + fprintf(stderr, "Invalid mapping for %llu-%llu, got " + "%llu-%llu\n", (unsigned long long)logical, + (unsigned long long)logical+len, + (unsigned long long)ce->start, + (unsigned long long)ce->start + ce->size); + return 1; + } + map = container_of(ce, struct map_lookup, ce); + + if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1)) + ret = map->num_stripes; + else if (map->type & BTRFS_BLOCK_GROUP_RAID10) + ret = map->sub_stripes; + else if (map->type & BTRFS_BLOCK_GROUP_RAID5) + ret = 2; + else if (map->type & BTRFS_BLOCK_GROUP_RAID6) + ret = 3; + else + ret = 1; + return ret; +} + +int btrfs_next_bg(struct btrfs_mapping_tree *map_tree, u64 *logical, + u64 *size, u64 type) +{ + struct cache_extent *ce; + struct map_lookup *map; + u64 cur = *logical; + + ce = search_cache_extent(&map_tree->cache_tree, cur); + + while (ce) { + /* + * only jump to next bg if our cur is not 0 + * As the initial logical for btrfs_next_bg() is 0, and + * if we jump to next bg, we skipped a valid bg. + */ + if (cur) { + ce = next_cache_extent(ce); + if (!ce) + return -ENOENT; + } + + cur = ce->start; + map = container_of(ce, struct map_lookup, ce); + if (map->type & type) { + *logical = ce->start; + *size = ce->size; + return 0; + } + } + + return -ENOENT; +} + +int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, + u64 chunk_start, u64 physical, u64 devid, + u64 **logical, int *naddrs, int *stripe_len) +{ + struct cache_extent *ce; + struct map_lookup *map; + u64 *buf; + u64 bytenr; + u64 length; + u64 stripe_nr; + u64 rmap_len; + int i, j, nr = 0; + + ce = search_cache_extent(&map_tree->cache_tree, chunk_start); + BUG_ON(!ce); + map = container_of(ce, struct map_lookup, ce); + + length = ce->size; + rmap_len = map->stripe_len; + if (map->type & BTRFS_BLOCK_GROUP_RAID10) + length = ce->size / (map->num_stripes / map->sub_stripes); + else if (map->type & BTRFS_BLOCK_GROUP_RAID0) + length = ce->size / map->num_stripes; + else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | + BTRFS_BLOCK_GROUP_RAID6)) { + length = ce->size / nr_data_stripes(map); + rmap_len = map->stripe_len * nr_data_stripes(map); + } + + buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); + + for (i = 0; i < map->num_stripes; i++) { + if (devid && map->stripes[i].dev->devid != devid) + continue; + if (map->stripes[i].physical > physical || + map->stripes[i].physical + length <= physical) + continue; + + stripe_nr = (physical - map->stripes[i].physical) / + map->stripe_len; + + if (map->type & BTRFS_BLOCK_GROUP_RAID10) { + stripe_nr = (stripe_nr * map->num_stripes + i) / + map->sub_stripes; + } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { + stripe_nr = stripe_nr * map->num_stripes + i; + } /* else if RAID[56], multiply by nr_data_stripes(). + * Alternatively, just use rmap_len below instead of + * map->stripe_len */ + + bytenr = ce->start + stripe_nr * rmap_len; + for (j = 0; j < nr; j++) { + if (buf[j] == bytenr) + break; + } + if (j == nr) + buf[nr++] = bytenr; + } + + *logical = buf; + *naddrs = nr; + *stripe_len = rmap_len; + + return 0; +} + +static inline int parity_smaller(u64 a, u64 b) +{ + return a > b; +} + +/* Bubble-sort the stripe set to put the parity/syndrome stripes last */ +static void sort_parity_stripes(struct btrfs_multi_bio *bbio, u64 *raid_map) +{ + struct btrfs_bio_stripe s; + int i; + u64 l; + int again = 1; + + while (again) { + again = 0; + for (i = 0; i < bbio->num_stripes - 1; i++) { + if (parity_smaller(raid_map[i], raid_map[i+1])) { + s = bbio->stripes[i]; + l = raid_map[i]; + bbio->stripes[i] = bbio->stripes[i+1]; + raid_map[i] = raid_map[i+1]; + bbio->stripes[i+1] = s; + raid_map[i+1] = l; + again = 1; + } + } + } +} + +int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, + u64 logical, u64 *length, + struct btrfs_multi_bio **multi_ret, int mirror_num, + u64 **raid_map_ret) +{ + return __btrfs_map_block(map_tree, rw, logical, length, NULL, + multi_ret, mirror_num, raid_map_ret); +} + +int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, + u64 logical, u64 *length, u64 *type, + struct btrfs_multi_bio **multi_ret, int mirror_num, + u64 **raid_map_ret) +{ + struct cache_extent *ce; + struct map_lookup *map; + u64 offset; + u64 stripe_offset; + u64 stripe_nr; + u64 *raid_map = NULL; + int stripes_allocated = 8; + int stripes_required = 1; + int stripe_index; + int i; + struct btrfs_multi_bio *multi = NULL; + + if (multi_ret && rw == READ) { + stripes_allocated = 1; + } +again: + ce = search_cache_extent(&map_tree->cache_tree, logical); + if (!ce) { + kfree(multi); + *length = (u64)-1; + return -ENOENT; + } + if (ce->start > logical) { + kfree(multi); + *length = ce->start - logical; + return -ENOENT; + } + + if (multi_ret) { + multi = kzalloc(btrfs_multi_bio_size(stripes_allocated), + GFP_NOFS); + if (!multi) + return -ENOMEM; + } + map = container_of(ce, struct map_lookup, ce); + offset = logical - ce->start; + + if (rw == WRITE) { + if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | + BTRFS_BLOCK_GROUP_DUP)) { + stripes_required = map->num_stripes; + } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { + stripes_required = map->sub_stripes; + } + } + if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6) + && multi_ret && ((rw & WRITE) || mirror_num > 1) && raid_map_ret) { + /* RAID[56] write or recovery. Return all stripes */ + stripes_required = map->num_stripes; + + /* Only allocate the map if we've already got a large enough multi_ret */ + if (stripes_allocated >= stripes_required) { + raid_map = kmalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); + if (!raid_map) { + kfree(multi); + return -ENOMEM; + } + } + } + + /* if our multi bio struct is too small, back off and try again */ + if (multi_ret && stripes_allocated < stripes_required) { + stripes_allocated = stripes_required; + kfree(multi); + multi = NULL; + goto again; + } + stripe_nr = offset; + /* + * stripe_nr counts the total number of stripes we have to stride + * to get to this block + */ + stripe_nr = stripe_nr / map->stripe_len; + + stripe_offset = stripe_nr * map->stripe_len; + BUG_ON(offset < stripe_offset); + + /* stripe_offset is the offset of this block in its stripe*/ + stripe_offset = offset - stripe_offset; + + if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | + BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 | + BTRFS_BLOCK_GROUP_RAID10 | + BTRFS_BLOCK_GROUP_DUP)) { + /* we limit the length of each bio to what fits in a stripe */ + *length = min_t(u64, ce->size - offset, + map->stripe_len - stripe_offset); + } else { + *length = ce->size - offset; + } + + if (!multi_ret) + goto out; + + multi->num_stripes = 1; + stripe_index = 0; + if (map->type & BTRFS_BLOCK_GROUP_RAID1) { + if (rw == WRITE) + multi->num_stripes = map->num_stripes; + else if (mirror_num) + stripe_index = mirror_num - 1; + else + stripe_index = stripe_nr % map->num_stripes; + } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { + int factor = map->num_stripes / map->sub_stripes; + + stripe_index = stripe_nr % factor; + stripe_index *= map->sub_stripes; + + if (rw == WRITE) + multi->num_stripes = map->sub_stripes; + else if (mirror_num) + stripe_index += mirror_num - 1; + + stripe_nr = stripe_nr / factor; + } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { + if (rw == WRITE) + multi->num_stripes = map->num_stripes; + else if (mirror_num) + stripe_index = mirror_num - 1; + } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | + BTRFS_BLOCK_GROUP_RAID6)) { + + if (raid_map) { + int rot; + u64 tmp; + u64 raid56_full_stripe_start; + u64 full_stripe_len = nr_data_stripes(map) * map->stripe_len; + + /* + * align the start of our data stripe in the logical + * address space + */ + raid56_full_stripe_start = offset / full_stripe_len; + raid56_full_stripe_start *= full_stripe_len; + + /* get the data stripe number */ + stripe_nr = raid56_full_stripe_start / map->stripe_len; + stripe_nr = stripe_nr / nr_data_stripes(map); + + /* Work out the disk rotation on this stripe-set */ + rot = stripe_nr % map->num_stripes; + + /* Fill in the logical address of each stripe */ + tmp = stripe_nr * nr_data_stripes(map); + + for (i = 0; i < nr_data_stripes(map); i++) + raid_map[(i+rot) % map->num_stripes] = + ce->start + (tmp + i) * map->stripe_len; + + raid_map[(i+rot) % map->num_stripes] = BTRFS_RAID5_P_STRIPE; + if (map->type & BTRFS_BLOCK_GROUP_RAID6) + raid_map[(i+rot+1) % map->num_stripes] = BTRFS_RAID6_Q_STRIPE; + + *length = map->stripe_len; + stripe_index = 0; + stripe_offset = 0; + multi->num_stripes = map->num_stripes; + } else { + stripe_index = stripe_nr % nr_data_stripes(map); + stripe_nr = stripe_nr / nr_data_stripes(map); + + /* + * Mirror #0 or #1 means the original data block. + * Mirror #2 is RAID5 parity block. + * Mirror #3 is RAID6 Q block. + */ + if (mirror_num > 1) + stripe_index = nr_data_stripes(map) + mirror_num - 2; + + /* We distribute the parity blocks across stripes */ + stripe_index = (stripe_nr + stripe_index) % map->num_stripes; + } + } else { + /* + * after this do_div call, stripe_nr is the number of stripes + * on this device we have to walk to find the data, and + * stripe_index is the number of our device in the stripe array + */ + stripe_index = stripe_nr % map->num_stripes; + stripe_nr = stripe_nr / map->num_stripes; + } + BUG_ON(stripe_index >= map->num_stripes); + + for (i = 0; i < multi->num_stripes; i++) { + multi->stripes[i].physical = + map->stripes[stripe_index].physical + stripe_offset + + stripe_nr * map->stripe_len; + multi->stripes[i].dev = map->stripes[stripe_index].dev; + stripe_index++; + } + *multi_ret = multi; + + if (type) + *type = map->type; + + if (raid_map) { + sort_parity_stripes(multi, raid_map); + *raid_map_ret = raid_map; + } +out: + return 0; +} + +struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid, + u8 *uuid, u8 *fsid) +{ + struct btrfs_device *device; + struct btrfs_fs_devices *cur_devices; + + cur_devices = root->fs_info->fs_devices; + while (cur_devices) { + if (!fsid || + (!memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE) || + root->fs_info->ignore_fsid_mismatch)) { + device = __find_device(&cur_devices->devices, + devid, uuid); + if (device) + return device; + } + cur_devices = cur_devices->seed; + } + return NULL; +} + +struct btrfs_device * +btrfs_find_device_by_devid(struct btrfs_fs_devices *fs_devices, + u64 devid, int instance) +{ + struct list_head *head = &fs_devices->devices; + struct btrfs_device *dev; + int num_found = 0; + + list_for_each_entry(dev, head, dev_list) { + if (dev->devid == devid && num_found++ == instance) + return dev; + } + return NULL; +} + +int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) +{ + struct cache_extent *ce; + struct map_lookup *map; + struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; + int readonly = 0; + int i; + + /* + * During chunk recovering, we may fail to find block group's + * corresponding chunk, we will rebuild it later + */ + ce = search_cache_extent(&map_tree->cache_tree, chunk_offset); + if (!root->fs_info->is_chunk_recover) + BUG_ON(!ce); + else + return 0; + + map = container_of(ce, struct map_lookup, ce); + for (i = 0; i < map->num_stripes; i++) { + if (!map->stripes[i].dev->writeable) { + readonly = 1; + break; + } + } + + return readonly; +} + +static struct btrfs_device *fill_missing_device(u64 devid) +{ + struct btrfs_device *device; + + device = kzalloc(sizeof(*device), GFP_NOFS); + device->devid = devid; + device->fd = -1; + return device; +} + +/* + * slot == -1: SYSTEM chunk + * return -EIO on error, otherwise return 0 + */ +static int btrfs_check_chunk_valid(struct btrfs_root *root, + struct extent_buffer *leaf, + struct btrfs_chunk *chunk, + int slot, u64 logical) +{ + u64 length; + u64 stripe_len; + u16 num_stripes; + u16 sub_stripes; + u64 type; + + length = btrfs_chunk_length(leaf, chunk); + stripe_len = btrfs_chunk_stripe_len(leaf, chunk); + num_stripes = btrfs_chunk_num_stripes(leaf, chunk); + sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); + type = btrfs_chunk_type(leaf, chunk); + + /* + * These valid checks may be insufficient to cover every corner cases. + */ + if (!IS_ALIGNED(logical, root->sectorsize)) { + error("invalid chunk logical %llu", logical); + return -EIO; + } + if (btrfs_chunk_sector_size(leaf, chunk) != root->sectorsize) { + error("invalid chunk sectorsize %llu", + (unsigned long long)btrfs_chunk_sector_size(leaf, chunk)); + return -EIO; + } + if (!length || !IS_ALIGNED(length, root->sectorsize)) { + error("invalid chunk length %llu", length); + return -EIO; + } + if (stripe_len != BTRFS_STRIPE_LEN) { + error("invalid chunk stripe length: %llu", stripe_len); + return -EIO; + } + /* Check on chunk item type */ + if (slot == -1 && (type & BTRFS_BLOCK_GROUP_SYSTEM) == 0) { + error("invalid chunk type %llu", type); + return -EIO; + } + if (type & ~(BTRFS_BLOCK_GROUP_TYPE_MASK | + BTRFS_BLOCK_GROUP_PROFILE_MASK)) { + error("unrecognized chunk type: %llu", + ~(BTRFS_BLOCK_GROUP_TYPE_MASK | + BTRFS_BLOCK_GROUP_PROFILE_MASK) & type); + return -EIO; + } + /* + * Btrfs_chunk contains at least one stripe, and for sys_chunk + * it can't exceed the system chunk array size + * For normal chunk, it should match its chunk item size. + */ + if (num_stripes < 1 || + (slot == -1 && sizeof(struct btrfs_stripe) * num_stripes > + BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) || + (slot >= 0 && sizeof(struct btrfs_stripe) * (num_stripes - 1) > + btrfs_item_size_nr(leaf, slot))) { + error("invalid num_stripes: %u", num_stripes); + return -EIO; + } + /* + * Device number check against profile + */ + if ((type & BTRFS_BLOCK_GROUP_RAID10 && sub_stripes == 0) || + (type & BTRFS_BLOCK_GROUP_RAID1 && num_stripes < 1) || + (type & BTRFS_BLOCK_GROUP_RAID5 && num_stripes < 2) || + (type & BTRFS_BLOCK_GROUP_RAID6 && num_stripes < 3) || + (type & BTRFS_BLOCK_GROUP_DUP && num_stripes > 2) || + ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 && + num_stripes != 1)) { + error("Invalid num_stripes:sub_stripes %u:%u for profile %llu", + num_stripes, sub_stripes, + type & BTRFS_BLOCK_GROUP_PROFILE_MASK); + return -EIO; + } + + return 0; +} + +/* + * Slot is used to verify the chunk item is valid + * + * For sys chunk in superblock, pass -1 to indicate sys chunk. + */ +static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, + struct extent_buffer *leaf, + struct btrfs_chunk *chunk, int slot) +{ + struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; + struct map_lookup *map; + struct cache_extent *ce; + u64 logical; + u64 length; + u64 devid; + u8 uuid[BTRFS_UUID_SIZE]; + int num_stripes; + int ret; + int i; + + logical = key->offset; + length = btrfs_chunk_length(leaf, chunk); + num_stripes = btrfs_chunk_num_stripes(leaf, chunk); + /* Validation check */ + ret = btrfs_check_chunk_valid(root, leaf, chunk, slot, logical); + if (ret) { + error("%s checksums match, but it has an invalid chunk, %s", + (slot == -1) ? "Superblock" : "Metadata", + (slot == -1) ? "try btrfsck --repair -s <superblock> ie, 0,1,2" : ""); + return ret; + } + + ce = search_cache_extent(&map_tree->cache_tree, logical); + + /* already mapped? */ + if (ce && ce->start <= logical && ce->start + ce->size > logical) { + return 0; + } + + map = kmalloc(btrfs_map_lookup_size(num_stripes), GFP_NOFS); + if (!map) + return -ENOMEM; + + map->ce.start = logical; + map->ce.size = length; + map->num_stripes = num_stripes; + map->io_width = btrfs_chunk_io_width(leaf, chunk); + map->io_align = btrfs_chunk_io_align(leaf, chunk); + map->sector_size = btrfs_chunk_sector_size(leaf, chunk); + map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); + map->type = btrfs_chunk_type(leaf, chunk); + map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); + + for (i = 0; i < num_stripes; i++) { + map->stripes[i].physical = + btrfs_stripe_offset_nr(leaf, chunk, i); + devid = btrfs_stripe_devid_nr(leaf, chunk, i); + read_extent_buffer(leaf, uuid, (unsigned long) + btrfs_stripe_dev_uuid_nr(chunk, i), + BTRFS_UUID_SIZE); + map->stripes[i].dev = btrfs_find_device(root, devid, uuid, + NULL); + if (!map->stripes[i].dev) { + map->stripes[i].dev = fill_missing_device(devid); + printf("warning, device %llu is missing\n", + (unsigned long long)devid); + } + + } + ret = insert_cache_extent(&map_tree->cache_tree, &map->ce); + BUG_ON(ret); + + return 0; +} + +static int fill_device_from_item(struct extent_buffer *leaf, + struct btrfs_dev_item *dev_item, + struct btrfs_device *device) +{ + unsigned long ptr; + + device->devid = btrfs_device_id(leaf, dev_item); + device->total_bytes = btrfs_device_total_bytes(leaf, dev_item); + device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); + device->type = btrfs_device_type(leaf, dev_item); + device->io_align = btrfs_device_io_align(leaf, dev_item); + device->io_width = btrfs_device_io_width(leaf, dev_item); + device->sector_size = btrfs_device_sector_size(leaf, dev_item); + + ptr = (unsigned long)btrfs_device_uuid(dev_item); + read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); + + return 0; +} + +static int open_seed_devices(struct btrfs_root *root, u8 *fsid) +{ + struct btrfs_fs_devices *fs_devices; + int ret; + + fs_devices = root->fs_info->fs_devices->seed; + while (fs_devices) { + if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) { + ret = 0; + goto out; + } + fs_devices = fs_devices->seed; + } + + fs_devices = find_fsid(fsid); + if (!fs_devices) { + /* missing all seed devices */ + fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); + if (!fs_devices) { + ret = -ENOMEM; + goto out; + } + INIT_LIST_HEAD(&fs_devices->devices); + list_add(&fs_devices->list, &fs_uuids); + memcpy(fs_devices->fsid, fsid, BTRFS_FSID_SIZE); + } + + ret = btrfs_open_devices(fs_devices, O_RDONLY); + if (ret) + goto out; + + fs_devices->seed = root->fs_info->fs_devices->seed; + root->fs_info->fs_devices->seed = fs_devices; +out: + return ret; +} + +static int read_one_dev(struct btrfs_root *root, + struct extent_buffer *leaf, + struct btrfs_dev_item *dev_item) +{ + struct btrfs_device *device; + u64 devid; + int ret = 0; + u8 fs_uuid[BTRFS_UUID_SIZE]; + u8 dev_uuid[BTRFS_UUID_SIZE]; + + devid = btrfs_device_id(leaf, dev_item); + read_extent_buffer(leaf, dev_uuid, + (unsigned long)btrfs_device_uuid(dev_item), + BTRFS_UUID_SIZE); + read_extent_buffer(leaf, fs_uuid, + (unsigned long)btrfs_device_fsid(dev_item), + BTRFS_UUID_SIZE); + + if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) { + ret = open_seed_devices(root, fs_uuid); + if (ret) + return ret; + } + + device = btrfs_find_device(root, devid, dev_uuid, fs_uuid); + if (!device) { + device = kzalloc(sizeof(*device), GFP_NOFS); + if (!device) + return -ENOMEM; + device->fd = -1; + list_add(&device->dev_list, + &root->fs_info->fs_devices->devices); + } + + fill_device_from_item(leaf, dev_item, device); + device->dev_root = root->fs_info->dev_root; + return ret; +} + +int btrfs_read_sys_array(struct btrfs_root *root) +{ + struct btrfs_super_block *super_copy = root->fs_info->super_copy; + struct extent_buffer *sb; + struct btrfs_disk_key *disk_key; + struct btrfs_chunk *chunk; + u8 *array_ptr; + unsigned long sb_array_offset; + int ret = 0; + u32 num_stripes; + u32 array_size; + u32 len = 0; + u32 cur_offset; + struct btrfs_key key; + + sb = btrfs_find_create_tree_block(root->fs_info, + BTRFS_SUPER_INFO_OFFSET, + BTRFS_SUPER_INFO_SIZE); + if (!sb) + return -ENOMEM; + btrfs_set_buffer_uptodate(sb); + write_extent_buffer(sb, super_copy, 0, sizeof(*super_copy)); + array_size = btrfs_super_sys_array_size(super_copy); + + array_ptr = super_copy->sys_chunk_array; + sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array); + cur_offset = 0; + + while (cur_offset < array_size) { + disk_key = (struct btrfs_disk_key *)array_ptr; + len = sizeof(*disk_key); + if (cur_offset + len > array_size) + goto out_short_read; + + btrfs_disk_key_to_cpu(&key, disk_key); + + array_ptr += len; + sb_array_offset += len; + cur_offset += len; + + if (key.type == BTRFS_CHUNK_ITEM_KEY) { + chunk = (struct btrfs_chunk *)sb_array_offset; + /* + * At least one btrfs_chunk with one stripe must be + * present, exact stripe count check comes afterwards + */ + len = btrfs_chunk_item_size(1); + if (cur_offset + len > array_size) + goto out_short_read; + + num_stripes = btrfs_chunk_num_stripes(sb, chunk); + if (!num_stripes) { + printk( + "ERROR: invalid number of stripes %u in sys_array at offset %u\n", + num_stripes, cur_offset); + ret = -EIO; + break; + } + + len = btrfs_chunk_item_size(num_stripes); + if (cur_offset + len > array_size) + goto out_short_read; + + ret = read_one_chunk(root, &key, sb, chunk, -1); + if (ret) + break; + } else { + printk( + "ERROR: unexpected item type %u in sys_array at offset %u\n", + (u32)key.type, cur_offset); + ret = -EIO; + break; + } + array_ptr += len; + sb_array_offset += len; + cur_offset += len; + } + free_extent_buffer(sb); + return ret; + +out_short_read: + printk("ERROR: sys_array too short to read %u bytes at offset %u\n", + len, cur_offset); + free_extent_buffer(sb); + return -EIO; +} + +int btrfs_read_chunk_tree(struct btrfs_root *root) +{ + struct btrfs_path *path; + struct extent_buffer *leaf; + struct btrfs_key key; + struct btrfs_key found_key; + int ret; + int slot; + + root = root->fs_info->chunk_root; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + /* + * Read all device items, and then all the chunk items. All + * device items are found before any chunk item (their object id + * is smaller than the lowest possible object id for a chunk + * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID). + */ + key.objectid = BTRFS_DEV_ITEMS_OBJECTID; + key.offset = 0; + key.type = 0; + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto error; + while(1) { + leaf = path->nodes[0]; + slot = path->slots[0]; + if (slot >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(root, path); + if (ret == 0) + continue; + if (ret < 0) + goto error; + break; + } + btrfs_item_key_to_cpu(leaf, &found_key, slot); + if (found_key.type == BTRFS_DEV_ITEM_KEY) { + struct btrfs_dev_item *dev_item; + dev_item = btrfs_item_ptr(leaf, slot, + struct btrfs_dev_item); + ret = read_one_dev(root, leaf, dev_item); + BUG_ON(ret); + } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { + struct btrfs_chunk *chunk; + chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); + ret = read_one_chunk(root, &found_key, leaf, chunk, + slot); + BUG_ON(ret); + } + path->slots[0]++; + } + + ret = 0; +error: + btrfs_free_path(path); + return ret; +} + +struct list_head *btrfs_scanned_uuids(void) +{ + return &fs_uuids; +} + +static int rmw_eb(struct btrfs_fs_info *info, + struct extent_buffer *eb, struct extent_buffer *orig_eb) +{ + int ret; + unsigned long orig_off = 0; + unsigned long dest_off = 0; + unsigned long copy_len = eb->len; + + ret = read_whole_eb(info, eb, 0); + if (ret) + return ret; + + if (eb->start + eb->len <= orig_eb->start || + eb->start >= orig_eb->start + orig_eb->len) + return 0; + /* + * | ----- orig_eb ------- | + * | ----- stripe ------- | + * | ----- orig_eb ------- | + * | ----- orig_eb ------- | + */ + if (eb->start > orig_eb->start) + orig_off = eb->start - orig_eb->start; + if (orig_eb->start > eb->start) + dest_off = orig_eb->start - eb->start; + + if (copy_len > orig_eb->len - orig_off) + copy_len = orig_eb->len - orig_off; + if (copy_len > eb->len - dest_off) + copy_len = eb->len - dest_off; + + memcpy(eb->data + dest_off, orig_eb->data + orig_off, copy_len); + return 0; +} + +static void split_eb_for_raid56(struct btrfs_fs_info *info, + struct extent_buffer *orig_eb, + struct extent_buffer **ebs, + u64 stripe_len, u64 *raid_map, + int num_stripes) +{ + struct extent_buffer *eb; + u64 start = orig_eb->start; + u64 this_eb_start; + int i; + int ret; + + for (i = 0; i < num_stripes; i++) { + if (raid_map[i] >= BTRFS_RAID5_P_STRIPE) + break; + + eb = calloc(1, sizeof(struct extent_buffer) + stripe_len); + if (!eb) + BUG(); + + eb->start = raid_map[i]; + eb->len = stripe_len; + eb->refs = 1; + eb->flags = 0; + eb->fd = -1; + eb->dev_bytenr = (u64)-1; + + this_eb_start = raid_map[i]; + + if (start > this_eb_start || + start + orig_eb->len < this_eb_start + stripe_len) { + ret = rmw_eb(info, eb, orig_eb); + BUG_ON(ret); + } else { + memcpy(eb->data, orig_eb->data + eb->start - start, stripe_len); + } + ebs[i] = eb; + } +} + +int write_raid56_with_parity(struct btrfs_fs_info *info, + struct extent_buffer *eb, + struct btrfs_multi_bio *multi, + u64 stripe_len, u64 *raid_map) +{ + struct extent_buffer **ebs, *p_eb = NULL, *q_eb = NULL; + int i; + int j; + int ret; + int alloc_size = eb->len; + + ebs = kmalloc(sizeof(*ebs) * multi->num_stripes, GFP_NOFS); + BUG_ON(!ebs); + + if (stripe_len > alloc_size) + alloc_size = stripe_len; + + split_eb_for_raid56(info, eb, ebs, stripe_len, raid_map, + multi->num_stripes); + + for (i = 0; i < multi->num_stripes; i++) { + struct extent_buffer *new_eb; + if (raid_map[i] < BTRFS_RAID5_P_STRIPE) { + ebs[i]->dev_bytenr = multi->stripes[i].physical; + ebs[i]->fd = multi->stripes[i].dev->fd; + multi->stripes[i].dev->total_ios++; + BUG_ON(ebs[i]->start != raid_map[i]); + continue; + } + new_eb = kmalloc(sizeof(*eb) + alloc_size, GFP_NOFS); + BUG_ON(!new_eb); + new_eb->dev_bytenr = multi->stripes[i].physical; + new_eb->fd = multi->stripes[i].dev->fd; + multi->stripes[i].dev->total_ios++; + new_eb->len = stripe_len; + + if (raid_map[i] == BTRFS_RAID5_P_STRIPE) + p_eb = new_eb; + else if (raid_map[i] == BTRFS_RAID6_Q_STRIPE) + q_eb = new_eb; + } + if (q_eb) { + void **pointers; + + pointers = kmalloc(sizeof(*pointers) * multi->num_stripes, + GFP_NOFS); + BUG_ON(!pointers); + + ebs[multi->num_stripes - 2] = p_eb; + ebs[multi->num_stripes - 1] = q_eb; + + for (i = 0; i < multi->num_stripes; i++) + pointers[i] = ebs[i]->data; + + raid6_gen_syndrome(multi->num_stripes, stripe_len, pointers); + kfree(pointers); + } else { + ebs[multi->num_stripes - 1] = p_eb; + memcpy(p_eb->data, ebs[0]->data, stripe_len); + for (j = 1; j < multi->num_stripes - 1; j++) { + for (i = 0; i < stripe_len; i += sizeof(unsigned long)) { + *(unsigned long *)(p_eb->data + i) ^= + *(unsigned long *)(ebs[j]->data + i); + } + } + } + + for (i = 0; i < multi->num_stripes; i++) { + ret = write_extent_to_disk(ebs[i]); + BUG_ON(ret); + if (ebs[i] != eb) + kfree(ebs[i]); + } + + kfree(ebs); + + return 0; +} |