blob: 03bfb8cca06f741747700228dc1f5154eb27aaaa [file] [log] [blame]
/*
* 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.
*/
#define _XOPEN_SOURCE 600
#define __USE_XOPEN2K
#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"
struct stripe {
struct btrfs_device *dev;
u64 physical;
};
struct map_lookup {
struct cache_extent ce;
u64 type;
int io_align;
int io_width;
int stripe_len;
int sector_size;
int num_stripes;
int sub_stripes;
struct btrfs_bio_stripe stripes[];
};
#define map_lookup_size(n) (sizeof(struct map_lookup) + \
(sizeof(struct btrfs_bio_stripe) * (n)))
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->devid = devid;
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);
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;
}
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 list_head *cur;
struct btrfs_device *device;
again:
list_for_each(cur, &fs_devices->devices) {
device = list_entry(cur, struct btrfs_device, dev_list);
close(device->fd);
device->fd = -1;
device->writeable = 0;
}
seed_devices = fs_devices->seed;
fs_devices->seed = NULL;
if (seed_devices) {
fs_devices = seed_devices;
goto again;
}
return 0;
}
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);
fd = open(device->name, flags);
if (fd < 0) {
ret = -errno;
goto fail;
}
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)
{
struct btrfs_super_block *disk_super;
char *buf;
int ret;
u64 devid;
char uuidbuf[37];
buf = malloc(4096);
if (!buf) {
ret = -ENOMEM;
goto error;
}
disk_super = (struct btrfs_super_block *)buf;
ret = btrfs_read_dev_super(fd, disk_super, super_offset);
if (ret < 0) {
ret = -EIO;
goto error_brelse;
}
devid = le64_to_cpu(disk_super->dev_item.devid);
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_METADUMP)
*total_devs = 1;
else
*total_devs = btrfs_super_num_devices(disk_super);
uuid_unparse(disk_super->fsid, uuidbuf);
ret = device_list_add(path, disk_super, devid, fs_devices_ret);
error_brelse:
free(buf);
error:
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 = 0;
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((u64)1024 * 1024, search_start);
if (root->fs_info->alloc_start + num_bytes <= device->total_bytes)
search_start = max(root->fs_info->alloc_start, search_start);
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(root, 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(root, path);
return ret;
}
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 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;
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(root, 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 > 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 div_factor(u64 num, int factor)
{
if (factor == 10)
return num;
num *= factor;
return num / 10;
}
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
return calc_size * num_stripes;
}
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 = extent_root->fs_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 = &extent_root->fs_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;
u64 max_avail = 0;
u64 percent_max;
int num_stripes = 1;
int min_stripes = 1;
int sub_stripes = 0;
int looped = 0;
int ret;
int index;
int stripe_len = 64 * 1024;
struct btrfs_key key;
if (list_empty(dev_list)) {
return -ENOSPC;
}
if (type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
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;
} else if (type & BTRFS_BLOCK_GROUP_DATA) {
calc_size = 1024 * 1024 * 1024;
max_chunk_size = 10 * calc_size;
min_stripe_size = 64 * 1024 * 1024;
} else if (type & BTRFS_BLOCK_GROUP_METADATA) {
calc_size = 1024 * 1024 * 1024;
max_chunk_size = 4 * calc_size;
min_stripe_size = 32 * 1024 * 1024;
}
}
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);
min_stripes = 2;
}
if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
num_stripes = btrfs_super_num_devices(&info->super_copy);
if (num_stripes < 4)
return -ENOSPC;
num_stripes &= ~(u32)1;
sub_stripes = 2;
min_stripes = 4;
}
/* 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);
avail = device->total_bytes - device->bytes_used;
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;
}
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.type = BTRFS_CHUNK_ITEM_KEY;
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(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);
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_existing_cache_extent(
&extent_root->fs_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;
}
int btrfs_alloc_data_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 = extent_root->fs_info->chunk_root;
struct btrfs_stripe *stripes;
struct btrfs_device *device = NULL;
struct btrfs_chunk *chunk;
struct list_head *dev_list = &extent_root->fs_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 = 64 * 1024;
struct btrfs_key key;
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.type = BTRFS_CHUNK_ITEM_KEY;
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(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);
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);
*start = key.offset;
map->ce.start = key.offset;
map->ce.size = num_bytes;
ret = insert_existing_cache_extent(
&extent_root->fs_info->mapping_tree.cache_tree,
&map->ce);
BUG_ON(ret);
kfree(chunk);
return ret;
}
void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
{
cache_tree_init(&tree->cache_tree);
}
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 = find_first_cache_extent(&map_tree->cache_tree, logical);
BUG_ON(!ce);
BUG_ON(ce->start > logical || ce->start + ce->size < logical);
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
ret = 1;
return ret;
}
int btrfs_next_metadata(struct btrfs_mapping_tree *map_tree, u64 *logical,
u64 *size)
{
struct cache_extent *ce;
struct map_lookup *map;
ce = find_first_cache_extent(&map_tree->cache_tree, *logical);
while (ce) {
ce = next_cache_extent(ce);
if (!ce)
return -ENOENT;
map = container_of(ce, struct map_lookup, ce);
if (map->type & BTRFS_BLOCK_GROUP_METADATA) {
*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;
int i, j, nr = 0;
ce = find_first_cache_extent(&map_tree->cache_tree, chunk_start);
BUG_ON(!ce);
map = container_of(ce, struct map_lookup, ce);
length = ce->size;
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;
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;
}
bytenr = ce->start + stripe_nr * map->stripe_len;
for (j = 0; j < nr; j++) {
if (buf[j] == bytenr)
break;
}
if (j == nr)
buf[nr++] = bytenr;
}
*logical = buf;
*naddrs = nr;
*stripe_len = map->stripe_len;
return 0;
}
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)
{
return __btrfs_map_block(map_tree, rw, logical, length, NULL,
multi_ret, mirror_num);
}
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)
{
struct cache_extent *ce;
struct map_lookup *map;
u64 offset;
u64 stripe_offset;
u64 stripe_nr;
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 = find_first_cache_extent(&map_tree->cache_tree, logical);
if (!ce) {
if (multi)
kfree(multi);
return -ENOENT;
}
if (ce->start > logical || ce->start + ce->size < logical) {
if (multi)
kfree(multi);
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 our multi bio struct is too small, back off and try again */
if (multi_ret && rw == WRITE &&
stripes_allocated < stripes_required) {
stripes_allocated = map->num_stripes;
kfree(multi);
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_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;
else
stripe_index = stripe_nr % map->sub_stripes;
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 {
/*
* 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;
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)) {
device = __find_device(&cur_devices->devices,
devid, uuid);
if (device)
return device;
}
cur_devices = cur_devices->seed;
}
return NULL;
}
int btrfs_bootstrap_super_map(struct btrfs_mapping_tree *map_tree,
struct btrfs_fs_devices *fs_devices)
{
struct map_lookup *map;
u64 logical = BTRFS_SUPER_INFO_OFFSET;
u64 length = BTRFS_SUPER_INFO_SIZE;
int num_stripes = 0;
int sub_stripes = 0;
int ret;
int i;
struct list_head *cur;
list_for_each(cur, &fs_devices->devices) {
num_stripes++;
}
map = kmalloc(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->sub_stripes = sub_stripes;
map->io_width = length;
map->io_align = length;
map->sector_size = length;
map->stripe_len = length;
map->type = BTRFS_BLOCK_GROUP_RAID1;
i = 0;
list_for_each(cur, &fs_devices->devices) {
struct btrfs_device *device = list_entry(cur,
struct btrfs_device,
dev_list);
map->stripes[i].physical = logical;
map->stripes[i].dev = device;
i++;
}
ret = insert_existing_cache_extent(&map_tree->cache_tree, &map->ce);
if (ret == -EEXIST) {
struct cache_extent *old;
struct map_lookup *old_map;
old = find_cache_extent(&map_tree->cache_tree, logical, length);
old_map = container_of(old, struct map_lookup, ce);
remove_cache_extent(&map_tree->cache_tree, old);
kfree(old_map);
ret = insert_existing_cache_extent(&map_tree->cache_tree,
&map->ce);
}
BUG_ON(ret);
return 0;
}
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;
ce = find_first_cache_extent(&map_tree->cache_tree, chunk_offset);
BUG_ON(!ce);
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;
}
static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
struct extent_buffer *leaf,
struct btrfs_chunk *chunk)
{
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);
ce = find_first_cache_extent(&map_tree->cache_tree, logical);
/* already mapped? */
if (ce && ce->start <= logical && ce->start + ce->size > logical) {
return 0;
}
num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
map = kmalloc(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_existing_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) {
ret = -ENOENT;
goto out;
}
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) {
printk("warning devid %llu not found already\n",
(unsigned long long)devid);
device = kmalloc(sizeof(*device), GFP_NOFS);
if (!device)
return -ENOMEM;
device->total_ios = 0;
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_super_device(struct btrfs_root *root, struct extent_buffer *buf)
{
struct btrfs_dev_item *dev_item;
dev_item = (struct btrfs_dev_item *)offsetof(struct btrfs_super_block,
dev_item);
return read_one_dev(root, buf, dev_item);
}
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;
struct btrfs_key key;
u32 num_stripes;
u32 array_size;
u32 len = 0;
u8 *ptr;
unsigned long sb_ptr;
u32 cur;
int ret = 0;
sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
BTRFS_SUPER_INFO_SIZE);
if (!sb)
return -ENOMEM;
btrfs_set_buffer_uptodate(sb);
write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
array_size = btrfs_super_sys_array_size(super_copy);
/*
* we do this loop twice, once for the device items and
* once for all of the chunks. This way there are device
* structs filled in for every chunk
*/
ptr = super_copy->sys_chunk_array;
sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
cur = 0;
while (cur < array_size) {
disk_key = (struct btrfs_disk_key *)ptr;
btrfs_disk_key_to_cpu(&key, disk_key);
len = sizeof(*disk_key);
ptr += len;
sb_ptr += len;
cur += len;
if (key.type == BTRFS_CHUNK_ITEM_KEY) {
chunk = (struct btrfs_chunk *)sb_ptr;
ret = read_one_chunk(root, &key, sb, chunk);
if (ret)
break;
num_stripes = btrfs_chunk_num_stripes(sb, chunk);
len = btrfs_chunk_item_size(num_stripes);
} else {
BUG();
}
ptr += len;
sb_ptr += len;
cur += len;
}
free_extent_buffer(sb);
return ret;
}
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;
/* first we search for all of the device items, and then we
* read in all of the chunk items. This way we can create chunk
* mappings that reference all of the devices that are afound
*/
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.offset = 0;
key.type = 0;
again:
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
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 (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
break;
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);
BUG_ON(ret);
}
path->slots[0]++;
}
if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
key.objectid = 0;
btrfs_release_path(root, path);
goto again;
}
btrfs_free_path(path);
ret = 0;
error:
return ret;
}
struct list_head *btrfs_scanned_uuids(void)
{
return &fs_uuids;
}