/* * 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 #include #include #include #include #include #include #include #include #include #include "compat.h" #include "ctree.h" #include "extent_map.h" #include "disk-io.h" #include "transaction.h" #include "print-tree.h" #include "volumes.h" #include "async-thread.h" #include "check-integrity.h" static int init_first_rw_device(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_device *device); static int btrfs_relocate_sys_chunks(struct btrfs_root *root); static DEFINE_MUTEX(uuid_mutex); static LIST_HEAD(fs_uuids); static void lock_chunks(struct btrfs_root *root) { mutex_lock(&root->fs_info->chunk_mutex); } static void unlock_chunks(struct btrfs_root *root) { mutex_unlock(&root->fs_info->chunk_mutex); } static void free_fs_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *device; WARN_ON(fs_devices->opened); while (!list_empty(&fs_devices->devices)) { device = list_entry(fs_devices->devices.next, struct btrfs_device, dev_list); list_del(&device->dev_list); kfree(device->name); kfree(device); } kfree(fs_devices); } int btrfs_cleanup_fs_uuids(void) { struct btrfs_fs_devices *fs_devices; while (!list_empty(&fs_uuids)) { fs_devices = list_entry(fs_uuids.next, struct btrfs_fs_devices, list); list_del(&fs_devices->list); free_fs_devices(fs_devices); } return 0; } static noinline struct btrfs_device *__find_device(struct list_head *head, u64 devid, u8 *uuid) { struct btrfs_device *dev; list_for_each_entry(dev, head, dev_list) { if (dev->devid == devid && (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { return dev; } } return NULL; } static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid) { struct btrfs_fs_devices *fs_devices; list_for_each_entry(fs_devices, &fs_uuids, list) { if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) return fs_devices; } return NULL; } static void requeue_list(struct btrfs_pending_bios *pending_bios, struct bio *head, struct bio *tail) { struct bio *old_head; old_head = pending_bios->head; pending_bios->head = head; if (pending_bios->tail) tail->bi_next = old_head; else pending_bios->tail = tail; } /* * we try to collect pending bios for a device so we don't get a large * number of procs sending bios down to the same device. This greatly * improves the schedulers ability to collect and merge the bios. * * But, it also turns into a long list of bios to process and that is sure * to eventually make the worker thread block. The solution here is to * make some progress and then put this work struct back at the end of * the list if the block device is congested. This way, multiple devices * can make progress from a single worker thread. */ static noinline int run_scheduled_bios(struct btrfs_device *device) { struct bio *pending; struct backing_dev_info *bdi; struct btrfs_fs_info *fs_info; struct btrfs_pending_bios *pending_bios; struct bio *tail; struct bio *cur; int again = 0; unsigned long num_run; unsigned long batch_run = 0; unsigned long limit; unsigned long last_waited = 0; int force_reg = 0; int sync_pending = 0; struct blk_plug plug; /* * this function runs all the bios we've collected for * a particular device. We don't want to wander off to * another device without first sending all of these down. * So, setup a plug here and finish it off before we return */ blk_start_plug(&plug); bdi = blk_get_backing_dev_info(device->bdev); fs_info = device->dev_root->fs_info; limit = btrfs_async_submit_limit(fs_info); limit = limit * 2 / 3; loop: spin_lock(&device->io_lock); loop_lock: num_run = 0; /* take all the bios off the list at once and process them * later on (without the lock held). But, remember the * tail and other pointers so the bios can be properly reinserted * into the list if we hit congestion */ if (!force_reg && device->pending_sync_bios.head) { pending_bios = &device->pending_sync_bios; force_reg = 1; } else { pending_bios = &device->pending_bios; force_reg = 0; } pending = pending_bios->head; tail = pending_bios->tail; WARN_ON(pending && !tail); /* * if pending was null this time around, no bios need processing * at all and we can stop. Otherwise it'll loop back up again * and do an additional check so no bios are missed. * * device->running_pending is used to synchronize with the * schedule_bio code. */ if (device->pending_sync_bios.head == NULL && device->pending_bios.head == NULL) { again = 0; device->running_pending = 0; } else { again = 1; device->running_pending = 1; } pending_bios->head = NULL; pending_bios->tail = NULL; spin_unlock(&device->io_lock); while (pending) { rmb(); /* we want to work on both lists, but do more bios on the * sync list than the regular list */ if ((num_run > 32 && pending_bios != &device->pending_sync_bios && device->pending_sync_bios.head) || (num_run > 64 && pending_bios == &device->pending_sync_bios && device->pending_bios.head)) { spin_lock(&device->io_lock); requeue_list(pending_bios, pending, tail); goto loop_lock; } cur = pending; pending = pending->bi_next; cur->bi_next = NULL; atomic_dec(&fs_info->nr_async_bios); if (atomic_read(&fs_info->nr_async_bios) < limit && waitqueue_active(&fs_info->async_submit_wait)) wake_up(&fs_info->async_submit_wait); BUG_ON(atomic_read(&cur->bi_cnt) == 0); /* * if we're doing the sync list, record that our * plug has some sync requests on it * * If we're doing the regular list and there are * sync requests sitting around, unplug before * we add more */ if (pending_bios == &device->pending_sync_bios) { sync_pending = 1; } else if (sync_pending) { blk_finish_plug(&plug); blk_start_plug(&plug); sync_pending = 0; } btrfsic_submit_bio(cur->bi_rw, cur); num_run++; batch_run++; if (need_resched()) cond_resched(); /* * we made progress, there is more work to do and the bdi * is now congested. Back off and let other work structs * run instead */ if (pending && bdi_write_congested(bdi) && batch_run > 8 && fs_info->fs_devices->open_devices > 1) { struct io_context *ioc; ioc = current->io_context; /* * the main goal here is that we don't want to * block if we're going to be able to submit * more requests without blocking. * * This code does two great things, it pokes into * the elevator code from a filesystem _and_ * it makes assumptions about how batching works. */ if (ioc && ioc->nr_batch_requests > 0 && time_before(jiffies, ioc->last_waited + HZ/50UL) && (last_waited == 0 || ioc->last_waited == last_waited)) { /* * we want to go through our batch of * requests and stop. So, we copy out * the ioc->last_waited time and test * against it before looping */ last_waited = ioc->last_waited; if (need_resched()) cond_resched(); continue; } spin_lock(&device->io_lock); requeue_list(pending_bios, pending, tail); device->running_pending = 1; spin_unlock(&device->io_lock); btrfs_requeue_work(&device->work); goto done; } /* unplug every 64 requests just for good measure */ if (batch_run % 64 == 0) { blk_finish_plug(&plug); blk_start_plug(&plug); sync_pending = 0; } } cond_resched(); if (again) goto loop; spin_lock(&device->io_lock); if (device->pending_bios.head || device->pending_sync_bios.head) goto loop_lock; spin_unlock(&device->io_lock); done: blk_finish_plug(&plug); return 0; } static void pending_bios_fn(struct btrfs_work *work) { struct btrfs_device *device; device = container_of(work, struct btrfs_device, work); run_scheduled_bios(device); } static noinline 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); char *name; 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); INIT_LIST_HEAD(&fs_devices->alloc_list); 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; mutex_init(&fs_devices->device_list_mutex); device = NULL; } else { device = __find_device(&fs_devices->devices, devid, disk_super->dev_item.uuid); } if (!device) { if (fs_devices->opened) return -EBUSY; device = kzalloc(sizeof(*device), GFP_NOFS); if (!device) { /* we can safely leave the fs_devices entry around */ return -ENOMEM; } device->devid = devid; device->work.func = pending_bios_fn; memcpy(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE); spin_lock_init(&device->io_lock); device->name = kstrdup(path, GFP_NOFS); if (!device->name) { kfree(device); return -ENOMEM; } INIT_LIST_HEAD(&device->dev_alloc_list); /* init readahead state */ spin_lock_init(&device->reada_lock); device->reada_curr_zone = NULL; atomic_set(&device->reada_in_flight, 0); device->reada_next = 0; INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT); INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT); mutex_lock(&fs_devices->device_list_mutex); list_add_rcu(&device->dev_list, &fs_devices->devices); mutex_unlock(&fs_devices->device_list_mutex); device->fs_devices = fs_devices; fs_devices->num_devices++; } else if (!device->name || strcmp(device->name, path)) { name = kstrdup(path, GFP_NOFS); if (!name) return -ENOMEM; kfree(device->name); device->name = name; if (device->missing) { fs_devices->missing_devices--; device->missing = 0; } } if (found_transid > fs_devices->latest_trans) { fs_devices->latest_devid = devid; fs_devices->latest_trans = found_transid; } *fs_devices_ret = fs_devices; return 0; } static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) { struct btrfs_fs_devices *fs_devices; struct btrfs_device *device; struct btrfs_device *orig_dev; fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); if (!fs_devices) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&fs_devices->devices); INIT_LIST_HEAD(&fs_devices->alloc_list); INIT_LIST_HEAD(&fs_devices->list); mutex_init(&fs_devices->device_list_mutex); fs_devices->latest_devid = orig->latest_devid; fs_devices->latest_trans = orig->latest_trans; memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid)); /* We have held the volume lock, it is safe to get the devices. */ list_for_each_entry(orig_dev, &orig->devices, dev_list) { device = kzalloc(sizeof(*device), GFP_NOFS); if (!device) goto error; device->name = kstrdup(orig_dev->name, GFP_NOFS); if (!device->name) { kfree(device); goto error; } device->devid = orig_dev->devid; device->work.func = pending_bios_fn; memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid)); spin_lock_init(&device->io_lock); INIT_LIST_HEAD(&device->dev_list); INIT_LIST_HEAD(&device->dev_alloc_list); list_add(&device->dev_list, &fs_devices->devices); device->fs_devices = fs_devices; fs_devices->num_devices++; } return fs_devices; error: free_fs_devices(fs_devices); return ERR_PTR(-ENOMEM); } int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *device, *next; mutex_lock(&uuid_mutex); again: /* This is the initialized path, it is safe to release the devices. */ list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { if (device->in_fs_metadata) continue; if (device->bdev) { blkdev_put(device->bdev, device->mode); device->bdev = NULL; fs_devices->open_devices--; } if (device->writeable) { list_del_init(&device->dev_alloc_list); device->writeable = 0; fs_devices->rw_devices--; } list_del_init(&device->dev_list); fs_devices->num_devices--; kfree(device->name); kfree(device); } if (fs_devices->seed) { fs_devices = fs_devices->seed; goto again; } mutex_unlock(&uuid_mutex); return 0; } static void __free_device(struct work_struct *work) { struct btrfs_device *device; device = container_of(work, struct btrfs_device, rcu_work); if (device->bdev) blkdev_put(device->bdev, device->mode); kfree(device->name); kfree(device); } static void free_device(struct rcu_head *head) { struct btrfs_device *device; device = container_of(head, struct btrfs_device, rcu); INIT_WORK(&device->rcu_work, __free_device); schedule_work(&device->rcu_work); } static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *device; if (--fs_devices->opened > 0) return 0; mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry(device, &fs_devices->devices, dev_list) { struct btrfs_device *new_device; if (device->bdev) fs_devices->open_devices--; if (device->writeable) { list_del_init(&device->dev_alloc_list); fs_devices->rw_devices--; } if (device->can_discard) fs_devices->num_can_discard--; new_device = kmalloc(sizeof(*new_device), GFP_NOFS); BUG_ON(!new_device); memcpy(new_device, device, sizeof(*new_device)); new_device->name = kstrdup(device->name, GFP_NOFS); BUG_ON(device->name && !new_device->name); new_device->bdev = NULL; new_device->writeable = 0; new_device->in_fs_metadata = 0; new_device->can_discard = 0; list_replace_rcu(&device->dev_list, &new_device->dev_list); call_rcu(&device->rcu, free_device); } mutex_unlock(&fs_devices->device_list_mutex); WARN_ON(fs_devices->open_devices); WARN_ON(fs_devices->rw_devices); fs_devices->opened = 0; fs_devices->seeding = 0; return 0; } int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_fs_devices *seed_devices = NULL; int ret; mutex_lock(&uuid_mutex); ret = __btrfs_close_devices(fs_devices); if (!fs_devices->opened) { seed_devices = fs_devices->seed; fs_devices->seed = NULL; } mutex_unlock(&uuid_mutex); while (seed_devices) { fs_devices = seed_devices; seed_devices = fs_devices->seed; __btrfs_close_devices(fs_devices); free_fs_devices(fs_devices); } return ret; } static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, fmode_t flags, void *holder) { struct request_queue *q; struct block_device *bdev; struct list_head *head = &fs_devices->devices; struct btrfs_device *device; struct block_device *latest_bdev = NULL; struct buffer_head *bh; struct btrfs_super_block *disk_super; u64 latest_devid = 0; u64 latest_transid = 0; u64 devid; int seeding = 1; int ret = 0; flags |= FMODE_EXCL; list_for_each_entry(device, head, dev_list) { if (device->bdev) continue; if (!device->name) continue; bdev = blkdev_get_by_path(device->name, flags, holder); if (IS_ERR(bdev)) { printk(KERN_INFO "open %s failed\n", device->name); goto error; } set_blocksize(bdev, 4096); bh = btrfs_read_dev_super(bdev); if (!bh) goto error_close; disk_super = (struct btrfs_super_block *)bh->b_data; devid = btrfs_stack_device_id(&disk_super->dev_item); if (devid != device->devid) goto error_brelse; if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE)) goto error_brelse; device->generation = btrfs_super_generation(disk_super); if (!latest_transid || device->generation > latest_transid) { latest_devid = devid; latest_transid = device->generation; latest_bdev = bdev; } if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { device->writeable = 0; } else { device->writeable = !bdev_read_only(bdev); seeding = 0; } q = bdev_get_queue(bdev); if (blk_queue_discard(q)) { device->can_discard = 1; fs_devices->num_can_discard++; } device->bdev = bdev; device->in_fs_metadata = 0; device->mode = flags; if (!blk_queue_nonrot(bdev_get_queue(bdev))) fs_devices->rotating = 1; fs_devices->open_devices++; if (device->writeable) { fs_devices->rw_devices++; list_add(&device->dev_alloc_list, &fs_devices->alloc_list); } brelse(bh); continue; error_brelse: brelse(bh); error_close: blkdev_put(bdev, flags); error: continue; } if (fs_devices->open_devices == 0) { ret = -EINVAL; goto out; } fs_devices->seeding = seeding; fs_devices->opened = 1; fs_devices->latest_bdev = latest_bdev; fs_devices->latest_devid = latest_devid; fs_devices->latest_trans = latest_transid; fs_devices->total_rw_bytes = 0; out: return ret; } int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, fmode_t flags, void *holder) { int ret; mutex_lock(&uuid_mutex); if (fs_devices->opened) { fs_devices->opened++; ret = 0; } else { ret = __btrfs_open_devices(fs_devices, flags, holder); } mutex_unlock(&uuid_mutex); return ret; } int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, struct btrfs_fs_devices **fs_devices_ret) { struct btrfs_super_block *disk_super; struct block_device *bdev; struct buffer_head *bh; int ret; u64 devid; u64 transid; flags |= FMODE_EXCL; bdev = blkdev_get_by_path(path, flags, holder); if (IS_ERR(bdev)) { ret = PTR_ERR(bdev); goto error; } mutex_lock(&uuid_mutex); ret = set_blocksize(bdev, 4096); if (ret) goto error_close; bh = btrfs_read_dev_super(bdev); if (!bh) { ret = -EINVAL; goto error_close; } disk_super = (struct btrfs_super_block *)bh->b_data; devid = btrfs_stack_device_id(&disk_super->dev_item); transid = btrfs_super_generation(disk_super); if (disk_super->label[0]) printk(KERN_INFO "device label %s ", disk_super->label); else printk(KERN_INFO "device fsid %pU ", disk_super->fsid); printk(KERN_CONT "devid %llu transid %llu %s\n", (unsigned long long)devid, (unsigned long long)transid, path); ret = device_list_add(path, disk_super, devid, fs_devices_ret); brelse(bh); error_close: mutex_unlock(&uuid_mutex); blkdev_put(bdev, flags); error: return ret; } /* helper to account the used device space in the range */ int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, u64 end, u64 *length) { struct btrfs_key key; struct btrfs_root *root = device->dev_root; struct btrfs_dev_extent *dev_extent; struct btrfs_path *path; u64 extent_end; int ret; int slot; struct extent_buffer *l; *length = 0; if (start >= device->total_bytes) return 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = 2; key.objectid = device->devid; key.offset = start; key.type = BTRFS_DEV_EXTENT_KEY; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; if (ret > 0) { ret = btrfs_previous_item(root, path, key.objectid, key.type); if (ret < 0) goto out; } 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 out; 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; dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); extent_end = key.offset + btrfs_dev_extent_length(l, dev_extent); if (key.offset <= start && extent_end > end) { *length = end - start + 1; break; } else if (key.offset <= start && extent_end > start) *length += extent_end - start; else if (key.offset > start && extent_end <= end) *length += extent_end - key.offset; else if (key.offset > start && key.offset <= end) { *length += end - key.offset + 1; break; } else if (key.offset > end) break; next: path->slots[0]++; } ret = 0; out: btrfs_free_path(path); return ret; } /* * find_free_dev_extent - find free space in the specified device * @device: the device which we search the free space in * @num_bytes: the size of the free space that we need * @start: store the start of the free space. * @len: the size of the free space. that we find, or the size of the max * free space if we don't find suitable free space * * 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 * * @start is used to store the start of the free space if we find. But if we * don't find suitable free space, it will be used to store the start position * of the max free space. * * @len is used to store the size of the free space that we find. * But if we don't find suitable free space, it is used to store the size of * the max free space. */ int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes, u64 *start, u64 *len) { struct btrfs_key key; struct btrfs_root *root = device->dev_root; struct btrfs_dev_extent *dev_extent; struct btrfs_path *path; u64 hole_size; u64 max_hole_start; u64 max_hole_size; u64 extent_end; u64 search_start; u64 search_end = device->total_bytes; int ret; int slot; struct extent_buffer *l; /* 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(root->fs_info->alloc_start, 1024ull * 1024); max_hole_start = search_start; max_hole_size = 0; hole_size = 0; if (search_start >= search_end) { ret = -ENOSPC; goto error; } path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto error; } path->reada = 2; key.objectid = device->devid; key.offset = search_start; key.type = BTRFS_DEV_EXTENT_KEY; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; if (ret > 0) { ret = btrfs_previous_item(root, path, key.objectid, key.type); if (ret < 0) goto out; } 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 out; 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_start) { hole_size = key.offset - search_start; if (hole_size > max_hole_size) { max_hole_start = search_start; max_hole_size = hole_size; } /* * If this free space is greater than which we need, * it must be the max free space that we have found * until now, so max_hole_start must point to the start * of this free space and the length of this free space * is stored in max_hole_size. Thus, we return * max_hole_start and max_hole_size and go back to the * caller. */ if (hole_size >= num_bytes) { ret = 0; goto out; } } 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; next: path->slots[0]++; cond_resched(); } /* * At this point, search_start should be the end of * allocated dev extents, and when shrinking the device, * search_end may be smaller than search_start. */ if (search_end > search_start) hole_size = search_end - search_start; if (hole_size > max_hole_size) { max_hole_start = search_start; max_hole_size = hole_size; } /* See above. */ if (hole_size < num_bytes) ret = -ENOSPC; else ret = 0; out: btrfs_free_path(path); error: *start = max_hole_start; if (len) *len = max_hole_size; return ret; } static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 start) { int ret; struct btrfs_path *path; struct btrfs_root *root = device->dev_root; struct btrfs_key key; struct btrfs_key found_key; struct extent_buffer *leaf = NULL; struct btrfs_dev_extent *extent = NULL; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = device->devid; key.offset = start; key.type = BTRFS_DEV_EXTENT_KEY; again: ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret > 0) { ret = btrfs_previous_item(root, path, key.objectid, BTRFS_DEV_EXTENT_KEY); if (ret) goto out; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); extent = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_extent); BUG_ON(found_key.offset > start || found_key.offset + btrfs_dev_extent_length(leaf, extent) < start); key = found_key; btrfs_release_path(path); goto again; } else if (ret == 0) { leaf = path->nodes[0]; extent = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_extent); } BUG_ON(ret); if (device->bytes_used > 0) { u64 len = btrfs_dev_extent_length(leaf, extent); device->bytes_used -= len; spin_lock(&root->fs_info->free_chunk_lock); root->fs_info->free_chunk_space += len; spin_unlock(&root->fs_info->free_chunk_lock); } ret = btrfs_del_item(trans, root, path); out: btrfs_free_path(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 start, u64 num_bytes) { 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; WARN_ON(!device->in_fs_metadata); path = btrfs_alloc_path(); if (!path) return -ENOMEM; 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); btrfs_free_path(path); return ret; } static noinline 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(); if (!path) return -ENOMEM; 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 noinline int find_next_devid(struct btrfs_root *root, u64 *objectid) { int ret; struct btrfs_key key; struct btrfs_key found_key; struct btrfs_path *path; root = 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 = (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_free_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; root = 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_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); 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; } static int btrfs_rm_dev_item(struct btrfs_root *root, struct btrfs_device *device) { int ret; struct btrfs_path *path; struct btrfs_key key; struct btrfs_trans_handle *trans; root = root->fs_info->chunk_root; path = btrfs_alloc_path(); if (!path) return -ENOMEM; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } key.objectid = BTRFS_DEV_ITEMS_OBJECTID; key.type = BTRFS_DEV_ITEM_KEY; key.offset = device->devid; lock_chunks(root); ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, root, path); if (ret) goto out; out: btrfs_free_path(path); unlock_chunks(root); btrfs_commit_transaction(trans, root); return ret; } int btrfs_rm_device(struct btrfs_root *root, char *device_path) { struct btrfs_device *device; struct btrfs_device *next_device; struct block_device *bdev; struct buffer_head *bh = NULL; struct btrfs_super_block *disk_super; struct btrfs_fs_devices *cur_devices; u64 all_avail; u64 devid; u64 num_devices; u8 *dev_uuid; int ret = 0; bool clear_super = false; mutex_lock(&uuid_mutex); all_avail = root->fs_info->avail_data_alloc_bits | root->fs_info->avail_system_alloc_bits | root->fs_info->avail_metadata_alloc_bits; if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && root->fs_info->fs_devices->num_devices <= 4) { printk(KERN_ERR "btrfs: unable to go below four devices " "on raid10\n"); ret = -EINVAL; goto out; } if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && root->fs_info->fs_devices->num_devices <= 2) { printk(KERN_ERR "btrfs: unable to go below two " "devices on raid1\n"); ret = -EINVAL; goto out; } if (strcmp(device_path, "missing") == 0) { struct list_head *devices; struct btrfs_device *tmp; device = NULL; devices = &root->fs_info->fs_devices->devices; /* * It is safe to read the devices since the volume_mutex * is held. */ list_for_each_entry(tmp, devices, dev_list) { if (tmp->in_fs_metadata && !tmp->bdev) { device = tmp; break; } } bdev = NULL; bh = NULL; disk_super = NULL; if (!device) { printk(KERN_ERR "btrfs: no missing devices found to " "remove\n"); goto out; } } else { bdev = blkdev_get_by_path(device_path, FMODE_READ | FMODE_EXCL, root->fs_info->bdev_holder); if (IS_ERR(bdev)) { ret = PTR_ERR(bdev); goto out; } set_blocksize(bdev, 4096); bh = btrfs_read_dev_super(bdev); if (!bh) { ret = -EINVAL; goto error_close; } disk_super = (struct btrfs_super_block *)bh->b_data; devid = btrfs_stack_device_id(&disk_super->dev_item); dev_uuid = disk_super->dev_item.uuid; device = btrfs_find_device(root, devid, dev_uuid, disk_super->fsid); if (!device) { ret = -ENOENT; goto error_brelse; } } if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) { printk(KERN_ERR "btrfs: unable to remove the only writeable " "device\n"); ret = -EINVAL; goto error_brelse; } if (device->writeable) { lock_chunks(root); list_del_init(&device->dev_alloc_list); unlock_chunks(root); root->fs_info->fs_devices->rw_devices--; clear_super = true; } ret = btrfs_shrink_device(device, 0); if (ret) goto error_undo; ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); if (ret) goto error_undo; spin_lock(&root->fs_info->free_chunk_lock); root->fs_info->free_chunk_space = device->total_bytes - device->bytes_used; spin_unlock(&root->fs_info->free_chunk_lock); device->in_fs_metadata = 0; btrfs_scrub_cancel_dev(root, device); /* * the device list mutex makes sure that we don't change * the device list while someone else is writing out all * the device supers. */ cur_devices = device->fs_devices; mutex_lock(&root->fs_info->fs_devices->device_list_mutex); list_del_rcu(&device->dev_list); device->fs_devices->num_devices--; if (device->missing) root->fs_info->fs_devices->missing_devices--; next_device = list_entry(root->fs_info->fs_devices->devices.next, struct btrfs_device, dev_list); if (device->bdev == root->fs_info->sb->s_bdev) root->fs_info->sb->s_bdev = next_device->bdev; if (device->bdev == root->fs_info->fs_devices->latest_bdev) root->fs_info->fs_devices->latest_bdev = next_device->bdev; if (device->bdev) device->fs_devices->open_devices--; call_rcu(&device->rcu, free_device); mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1; btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices); if (cur_devices->open_devices == 0) { struct btrfs_fs_devices *fs_devices; fs_devices = root->fs_info->fs_devices; while (fs_devices) { if (fs_devices->seed == cur_devices) break; fs_devices = fs_devices->seed; } fs_devices->seed = cur_devices->seed; cur_devices->seed = NULL; lock_chunks(root); __btrfs_close_devices(cur_devices); unlock_chunks(root); free_fs_devices(cur_devices); } /* * at this point, the device is zero sized. We want to * remove it from the devices list and zero out the old super */ if (clear_super) { /* make sure this device isn't detected as part of * the FS anymore */ memset(&disk_super->magic, 0, sizeof(disk_super->magic)); set_buffer_dirty(bh); sync_dirty_buffer(bh); } ret = 0; error_brelse: brelse(bh); error_close: if (bdev) blkdev_put(bdev, FMODE_READ | FMODE_EXCL); out: mutex_unlock(&uuid_mutex); return ret; error_undo: if (device->writeable) { lock_chunks(root); list_add(&device->dev_alloc_list, &root->fs_info->fs_devices->alloc_list); unlock_chunks(root); root->fs_info->fs_devices->rw_devices++; } goto error_brelse; } /* * does all the dirty work required for changing file system's UUID. */ static int btrfs_prepare_sprout(struct btrfs_root *root) { struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; struct btrfs_fs_devices *old_devices; struct btrfs_fs_devices *seed_devices; struct btrfs_super_block *disk_super = root->fs_info->super_copy; struct btrfs_device *device; u64 super_flags; BUG_ON(!mutex_is_locked(&uuid_mutex)); if (!fs_devices->seeding) return -EINVAL; seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); if (!seed_devices) return -ENOMEM; old_devices = clone_fs_devices(fs_devices); if (IS_ERR(old_devices)) { kfree(seed_devices); return PTR_ERR(old_devices); } list_add(&old_devices->list, &fs_uuids); memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); seed_devices->opened = 1; INIT_LIST_HEAD(&seed_devices->devices); INIT_LIST_HEAD(&seed_devices->alloc_list); mutex_init(&seed_devices->device_list_mutex); mutex_lock(&root->fs_info->fs_devices->device_list_mutex); list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, synchronize_rcu); mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); list_for_each_entry(device, &seed_devices->devices, dev_list) { device->fs_devices = seed_devices; } fs_devices->seeding = 0; fs_devices->num_devices = 0; fs_devices->open_devices = 0; fs_devices->seed = seed_devices; generate_random_uuid(fs_devices->fsid); memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); super_flags = btrfs_super_flags(disk_super) & ~BTRFS_SUPER_FLAG_SEEDING; btrfs_set_super_flags(disk_super, super_flags); return 0; } /* * strore the expected generation for seed devices in device items. */ static int btrfs_finish_sprout(struct btrfs_trans_handle *trans, struct btrfs_root *root) { struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_dev_item *dev_item; struct btrfs_device *device; struct btrfs_key key; u8 fs_uuid[BTRFS_UUID_SIZE]; u8 dev_uuid[BTRFS_UUID_SIZE]; u64 devid; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; root = root->fs_info->chunk_root; key.objectid = BTRFS_DEV_ITEMS_OBJECTID; key.offset = 0; key.type = BTRFS_DEV_ITEM_KEY; while (1) { ret = btrfs_search_slot(trans, root, &key, path, 0, 1); if (ret < 0) goto error; leaf = path->nodes[0]; next_slot: if (path->slots[0] >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret > 0) break; if (ret < 0) goto error; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); btrfs_release_path(path); continue; } btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || key.type != BTRFS_DEV_ITEM_KEY) break; dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 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); device = btrfs_find_device(root, devid, dev_uuid, fs_uuid); BUG_ON(!device); if (device->fs_devices->seeding) { btrfs_set_device_generation(leaf, dev_item, device->generation); btrfs_mark_buffer_dirty(leaf); } path->slots[0]++; goto next_slot; } ret = 0; error: btrfs_free_path(path); return ret; } int btrfs_init_new_device(struct btrfs_root *root, char *device_path) { struct request_queue *q; struct btrfs_trans_handle *trans; struct btrfs_device *device; struct block_device *bdev; struct list_head *devices; struct super_block *sb = root->fs_info->sb; u64 total_bytes; int seeding_dev = 0; int ret = 0; if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) return -EINVAL; bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, root->fs_info->bdev_holder); if (IS_ERR(bdev)) return PTR_ERR(bdev); if (root->fs_info->fs_devices->seeding) { seeding_dev = 1; down_write(&sb->s_umount); mutex_lock(&uuid_mutex); } filemap_write_and_wait(bdev->bd_inode->i_mapping); devices = &root->fs_info->fs_devices->devices; /* * we have the volume lock, so we don't need the extra * device list mutex while reading the list here. */ list_for_each_entry(device, devices, dev_list) { if (device->bdev == bdev) { ret = -EEXIST; goto error; } } device = kzalloc(sizeof(*device), GFP_NOFS); if (!device) { /* we can safely leave the fs_devices entry around */ ret = -ENOMEM; goto error; } device->name = kstrdup(device_path, GFP_NOFS); if (!device->name) { kfree(device); ret = -ENOMEM; goto error; } ret = find_next_devid(root, &device->devid); if (ret) { kfree(device->name); kfree(device); goto error; } trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { kfree(device->name); kfree(device); ret = PTR_ERR(trans); goto error; } lock_chunks(root); q = bdev_get_queue(bdev); if (blk_queue_discard(q)) device->can_discard = 1; device->writeable = 1; device->work.func = pending_bios_fn; generate_random_uuid(device->uuid); spin_lock_init(&device->io_lock); device->generation = trans->transid; device->io_width = root->sectorsize; device->io_align = root->sectorsize; device->sector_size = root->sectorsize; device->total_bytes = i_size_read(bdev->bd_inode); device->disk_total_bytes = device->total_bytes; device->dev_root = root->fs_info->dev_root; device->bdev = bdev; device->in_fs_metadata = 1; device->mode = FMODE_EXCL; set_blocksize(device->bdev, 4096); if (seeding_dev) { sb->s_flags &= ~MS_RDONLY; ret = btrfs_prepare_sprout(root); BUG_ON(ret); } device->fs_devices = root->fs_info->fs_devices; /* * we don't want write_supers to jump in here with our device * half setup */ mutex_lock(&root->fs_info->fs_devices->device_list_mutex); list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices); list_add(&device->dev_alloc_list, &root->fs_info->fs_devices->alloc_list); root->fs_info->fs_devices->num_devices++; root->fs_info->fs_devices->open_devices++; root->fs_info->fs_devices->rw_devices++; if (device->can_discard) root->fs_info->fs_devices->num_can_discard++; root->fs_info->fs_devices->total_rw_bytes += device->total_bytes; spin_lock(&root->fs_info->free_chunk_lock); root->fs_info->free_chunk_space += device->total_bytes; spin_unlock(&root->fs_info->free_chunk_lock); if (!blk_queue_nonrot(bdev_get_queue(bdev))) root->fs_info->fs_devices->rotating = 1; total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); btrfs_set_super_total_bytes(root->fs_info->super_copy, total_bytes + device->total_bytes); total_bytes = btrfs_super_num_devices(root->fs_info->super_copy); btrfs_set_super_num_devices(root->fs_info->super_copy, total_bytes + 1); mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); if (seeding_dev) { ret = init_first_rw_device(trans, root, device); BUG_ON(ret); ret = btrfs_finish_sprout(trans, root); BUG_ON(ret); } else { ret = btrfs_add_device(trans, root, device); } /* * we've got more storage, clear any full flags on the space * infos */ btrfs_clear_space_info_full(root->fs_info); unlock_chunks(root); btrfs_commit_transaction(trans, root); if (seeding_dev) { mutex_unlock(&uuid_mutex); up_write(&sb->s_umount); ret = btrfs_relocate_sys_chunks(root); BUG_ON(ret); } return ret; error: blkdev_put(bdev, FMODE_EXCL); if (seeding_dev) { mutex_unlock(&uuid_mutex); up_write(&sb->s_umount); } return ret; } static noinline 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->disk_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; } static int __btrfs_grow_device(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 new_size) { struct btrfs_super_block *super_copy = device->dev_root->fs_info->super_copy; u64 old_total = btrfs_super_total_bytes(super_copy); u64 diff = new_size - device->total_bytes; if (!device->writeable) return -EACCES; if (new_size <= device->total_bytes) return -EINVAL; btrfs_set_super_total_bytes(super_copy, old_total + diff); device->fs_devices->total_rw_bytes += diff; device->total_bytes = new_size; device->disk_total_bytes = new_size; btrfs_clear_space_info_full(device->dev_root->fs_info); return btrfs_update_device(trans, device); } int btrfs_grow_device(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 new_size) { int ret; lock_chunks(device->dev_root); ret = __btrfs_grow_device(trans, device, new_size); unlock_chunks(device->dev_root); return ret; } static int btrfs_free_chunk(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 chunk_tree, u64 chunk_objectid, u64 chunk_offset) { int ret; struct btrfs_path *path; struct btrfs_key key; root = root->fs_info->chunk_root; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = chunk_objectid; key.offset = chunk_offset; key.type = BTRFS_CHUNK_ITEM_KEY; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); BUG_ON(ret); ret = btrfs_del_item(trans, root, path); btrfs_free_path(path); return ret; } static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 chunk_offset) { struct btrfs_super_block *super_copy = root->fs_info->super_copy; struct btrfs_disk_key *disk_key; struct btrfs_chunk *chunk; u8 *ptr; int ret = 0; u32 num_stripes; u32 array_size; u32 len = 0; u32 cur; struct btrfs_key key; array_size = btrfs_super_sys_array_size(super_copy); ptr = super_copy->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); if (key.type == BTRFS_CHUNK_ITEM_KEY) { chunk = (struct btrfs_chunk *)(ptr + len); num_stripes = btrfs_stack_chunk_num_stripes(chunk); len += btrfs_chunk_item_size(num_stripes); } else { ret = -EIO; break; } if (key.objectid == chunk_objectid && key.offset == chunk_offset) { memmove(ptr, ptr + len, array_size - (cur + len)); array_size -= len; btrfs_set_super_sys_array_size(super_copy, array_size); } else { ptr += len; cur += len; } } return ret; } static int btrfs_relocate_chunk(struct btrfs_root *root, u64 chunk_tree, u64 chunk_objectid, u64 chunk_offset) { struct extent_map_tree *em_tree; struct btrfs_root *extent_root; struct btrfs_trans_handle *trans; struct extent_map *em; struct map_lookup *map; int ret; int i; root = root->fs_info->chunk_root; extent_root = root->fs_info->extent_root; em_tree = &root->fs_info->mapping_tree.map_tree; ret = btrfs_can_relocate(extent_root, chunk_offset); if (ret) return -ENOSPC; /* step one, relocate all the extents inside this chunk */ ret = btrfs_relocate_block_group(extent_root, chunk_offset); if (ret) return ret; trans = btrfs_start_transaction(root, 0); BUG_ON(IS_ERR(trans)); lock_chunks(root); /* * step two, delete the device extents and the * chunk tree entries */ read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, chunk_offset, 1); read_unlock(&em_tree->lock); BUG_ON(em->start > chunk_offset || em->start + em->len < chunk_offset); map = (struct map_lookup *)em->bdev; for (i = 0; i < map->num_stripes; i++) { ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, map->stripes[i].physical); BUG_ON(ret); if (map->stripes[i].dev) { ret = btrfs_update_device(trans, map->stripes[i].dev); BUG_ON(ret); } } ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, chunk_offset); BUG_ON(ret); trace_btrfs_chunk_free(root, map, chunk_offset, em->len); if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); BUG_ON(ret); } ret = btrfs_remove_block_group(trans, extent_root, chunk_offset); BUG_ON(ret); write_lock(&em_tree->lock); remove_extent_mapping(em_tree, em); write_unlock(&em_tree->lock); kfree(map); em->bdev = NULL; /* once for the tree */ free_extent_map(em); /* once for us */ free_extent_map(em); unlock_chunks(root); btrfs_end_transaction(trans, root); return 0; } static int btrfs_relocate_sys_chunks(struct btrfs_root *root) { struct btrfs_root *chunk_root = root->fs_info->chunk_root; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_chunk *chunk; struct btrfs_key key; struct btrfs_key found_key; u64 chunk_tree = chunk_root->root_key.objectid; u64 chunk_type; bool retried = false; int failed = 0; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; again: key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.offset = (u64)-1; key.type = BTRFS_CHUNK_ITEM_KEY; while (1) { ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); if (ret < 0) goto error; BUG_ON(ret == 0); ret = btrfs_previous_item(chunk_root, path, key.objectid, key.type); if (ret < 0) goto error; if (ret > 0) break; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); chunk = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_chunk); chunk_type = btrfs_chunk_type(leaf, chunk); btrfs_release_path(path); if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { ret = btrfs_relocate_chunk(chunk_root, chunk_tree, found_key.objectid, found_key.offset); if (ret == -ENOSPC) failed++; else if (ret) BUG(); } if (found_key.offset == 0) break; key.offset = found_key.offset - 1; } ret = 0; if (failed && !retried) { failed = 0; retried = true; goto again; } else if (failed && retried) { WARN_ON(1); ret = -ENOSPC; } error: btrfs_free_path(path); return ret; } static int insert_balance_item(struct btrfs_root *root, struct btrfs_balance_control *bctl) { struct btrfs_trans_handle *trans; struct btrfs_balance_item *item; struct btrfs_disk_balance_args disk_bargs; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key; int ret, err; path = btrfs_alloc_path(); if (!path) return -ENOMEM; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } key.objectid = BTRFS_BALANCE_OBJECTID; key.type = BTRFS_BALANCE_ITEM_KEY; key.offset = 0; ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*item)); if (ret) goto out; leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); btrfs_set_balance_data(leaf, item, &disk_bargs); btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); btrfs_set_balance_meta(leaf, item, &disk_bargs); btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); btrfs_set_balance_sys(leaf, item, &disk_bargs); btrfs_set_balance_flags(leaf, item, bctl->flags); btrfs_mark_buffer_dirty(leaf); out: btrfs_free_path(path); err = btrfs_commit_transaction(trans, root); if (err && !ret) ret = err; return ret; } static int del_balance_item(struct btrfs_root *root) { struct btrfs_trans_handle *trans; struct btrfs_path *path; struct btrfs_key key; int ret, err; path = btrfs_alloc_path(); if (!path) return -ENOMEM; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } key.objectid = BTRFS_BALANCE_OBJECTID; key.type = BTRFS_BALANCE_ITEM_KEY; key.offset = 0; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, root, path); out: btrfs_free_path(path); err = btrfs_commit_transaction(trans, root); if (err && !ret) ret = err; return ret; } /* * This is a heuristic used to reduce the number of chunks balanced on * resume after balance was interrupted. */ static void update_balance_args(struct btrfs_balance_control *bctl) { /* * Turn on soft mode for chunk types that were being converted. */ if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; /* * Turn on usage filter if is not already used. The idea is * that chunks that we have already balanced should be * reasonably full. Don't do it for chunks that are being * converted - that will keep us from relocating unconverted * (albeit full) chunks. */ if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; bctl->data.usage = 90; } if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; bctl->sys.usage = 90; } if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; bctl->meta.usage = 90; } } /* * Should be called with both balance and volume mutexes held to * serialize other volume operations (add_dev/rm_dev/resize) with * restriper. Same goes for unset_balance_control. */ static void set_balance_control(struct btrfs_balance_control *bctl) { struct btrfs_fs_info *fs_info = bctl->fs_info; BUG_ON(fs_info->balance_ctl); spin_lock(&fs_info->balance_lock); fs_info->balance_ctl = bctl; spin_unlock(&fs_info->balance_lock); } static void unset_balance_control(struct btrfs_fs_info *fs_info) { struct btrfs_balance_control *bctl = fs_info->balance_ctl; BUG_ON(!fs_info->balance_ctl); spin_lock(&fs_info->balance_lock); fs_info->balance_ctl = NULL; spin_unlock(&fs_info->balance_lock); kfree(bctl); } /* * Balance filters. Return 1 if chunk should be filtered out * (should not be balanced). */ static int chunk_profiles_filter(u64 chunk_profile, struct btrfs_balance_args *bargs) { chunk_profile &= BTRFS_BLOCK_GROUP_PROFILE_MASK; if (chunk_profile == 0) chunk_profile = BTRFS_AVAIL_ALLOC_BIT_SINGLE; if (bargs->profiles & chunk_profile) return 0; return 1; } static u64 div_factor_fine(u64 num, int factor) { if (factor <= 0) return 0; if (factor >= 100) return num; num *= factor; do_div(num, 100); return num; } static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, struct btrfs_balance_args *bargs) { struct btrfs_block_group_cache *cache; u64 chunk_used, user_thresh; int ret = 1; cache = btrfs_lookup_block_group(fs_info, chunk_offset); chunk_used = btrfs_block_group_used(&cache->item); user_thresh = div_factor_fine(cache->key.offset, bargs->usage); if (chunk_used < user_thresh) ret = 0; btrfs_put_block_group(cache); return ret; } static int chunk_devid_filter(struct extent_buffer *leaf, struct btrfs_chunk *chunk, struct btrfs_balance_args *bargs) { struct btrfs_stripe *stripe; int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); int i; for (i = 0; i < num_stripes; i++) { stripe = btrfs_stripe_nr(chunk, i); if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) return 0; } return 1; } /* [pstart, pend) */ static int chunk_drange_filter(struct extent_buffer *leaf, struct btrfs_chunk *chunk, u64 chunk_offset, struct btrfs_balance_args *bargs) { struct btrfs_stripe *stripe; int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); u64 stripe_offset; u64 stripe_length; int factor; int i; if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) return 0; if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) factor = 2; else factor = 1; factor = num_stripes / factor; for (i = 0; i < num_stripes; i++) { stripe = btrfs_stripe_nr(chunk, i); if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) continue; stripe_offset = btrfs_stripe_offset(leaf, stripe); stripe_length = btrfs_chunk_length(leaf, chunk); do_div(stripe_length, factor); if (stripe_offset < bargs->pend && stripe_offset + stripe_length > bargs->pstart) return 0; } return 1; } /* [vstart, vend) */ static int chunk_vrange_filter(struct extent_buffer *leaf, struct btrfs_chunk *chunk, u64 chunk_offset, struct btrfs_balance_args *bargs) { if (chunk_offset < bargs->vend && chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) /* at least part of the chunk is inside this vrange */ return 0; return 1; } static int chunk_soft_convert_filter(u64 chunk_profile, struct btrfs_balance_args *bargs) { if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) return 0; chunk_profile &= BTRFS_BLOCK_GROUP_PROFILE_MASK; if (chunk_profile == 0) chunk_profile = BTRFS_AVAIL_ALLOC_BIT_SINGLE; if (bargs->target & chunk_profile) return 1; return 0; } static int should_balance_chunk(struct btrfs_root *root, struct extent_buffer *leaf, struct btrfs_chunk *chunk, u64 chunk_offset) { struct btrfs_balance_control *bctl = root->fs_info->balance_ctl; struct btrfs_balance_args *bargs = NULL; u64 chunk_type = btrfs_chunk_type(leaf, chunk); /* type filter */ if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { return 0; } if (chunk_type & BTRFS_BLOCK_GROUP_DATA) bargs = &bctl->data; else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) bargs = &bctl->sys; else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) bargs = &bctl->meta; /* profiles filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && chunk_profiles_filter(chunk_type, bargs)) { return 0; } /* usage filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) { return 0; } /* devid filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && chunk_devid_filter(leaf, chunk, bargs)) { return 0; } /* drange filter, makes sense only with devid filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) { return 0; } /* vrange filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { return 0; } /* soft profile changing mode */ if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && chunk_soft_convert_filter(chunk_type, bargs)) { return 0; } return 1; } static u64 div_factor(u64 num, int factor) { if (factor == 10) return num; num *= factor; do_div(num, 10); return num; } static int __btrfs_balance(struct btrfs_fs_info *fs_info) { struct btrfs_balance_control *bctl = fs_info->balance_ctl; struct btrfs_root *chunk_root = fs_info->chunk_root; struct btrfs_root *dev_root = fs_info->dev_root; struct list_head *devices; struct btrfs_device *device; u64 old_size; u64 size_to_free; struct btrfs_chunk *chunk; struct btrfs_path *path; struct btrfs_key key; struct btrfs_key found_key; struct btrfs_trans_handle *trans; struct extent_buffer *leaf; int slot; int ret; int enospc_errors = 0; bool counting = true; /* step one make some room on all the devices */ devices = &fs_info->fs_devices->devices; list_for_each_entry(device, devices, dev_list) { old_size = device->total_bytes; size_to_free = div_factor(old_size, 1); size_to_free = min(size_to_free, (u64)1 * 1024 * 1024); if (!device->writeable || device->total_bytes - device->bytes_used > size_to_free) continue; ret = btrfs_shrink_device(device, old_size - size_to_free); if (ret == -ENOSPC) break; BUG_ON(ret); trans = btrfs_start_transaction(dev_root, 0); BUG_ON(IS_ERR(trans)); ret = btrfs_grow_device(trans, device, old_size); BUG_ON(ret); btrfs_end_transaction(trans, dev_root); } /* step two, relocate all the chunks */ path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto error; } /* zero out stat counters */ spin_lock(&fs_info->balance_lock); memset(&bctl->stat, 0, sizeof(bctl->stat)); spin_unlock(&fs_info->balance_lock); again: key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.offset = (u64)-1; key.type = BTRFS_CHUNK_ITEM_KEY; while (1) { if ((!counting && atomic_read(&fs_info->balance_pause_req)) || atomic_read(&fs_info->balance_cancel_req)) { ret = -ECANCELED; goto error; } ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); if (ret < 0) goto error; /* * this shouldn't happen, it means the last relocate * failed */ if (ret == 0) BUG(); /* FIXME break ? */ ret = btrfs_previous_item(chunk_root, path, 0, BTRFS_CHUNK_ITEM_KEY); if (ret) { ret = 0; break; } leaf = path->nodes[0]; slot = path->slots[0]; btrfs_item_key_to_cpu(leaf, &found_key, slot); if (found_key.objectid != key.objectid) break; /* chunk zero is special */ if (found_key.offset == 0) break; chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); if (!counting) { spin_lock(&fs_info->balance_lock); bctl->stat.considered++; spin_unlock(&fs_info->balance_lock); } ret = should_balance_chunk(chunk_root, leaf, chunk, found_key.offset); btrfs_release_path(path); if (!ret) goto loop; if (counting) { spin_lock(&fs_info->balance_lock); bctl->stat.expected++; spin_unlock(&fs_info->balance_lock); goto loop; } ret = btrfs_relocate_chunk(chunk_root, chunk_root->root_key.objectid, found_key.objectid, found_key.offset); if (ret && ret != -ENOSPC) goto error; if (ret == -ENOSPC) { enospc_errors++; } else { spin_lock(&fs_info->balance_lock); bctl->stat.completed++; spin_unlock(&fs_info->balance_lock); } loop: key.offset = found_key.offset - 1; } if (counting) { btrfs_release_path(path); counting = false; goto again; } error: btrfs_free_path(path); if (enospc_errors) { printk(KERN_INFO "btrfs: %d enospc errors during balance\n", enospc_errors); if (!ret) ret = -ENOSPC; } return ret; } static inline int balance_need_close(struct btrfs_fs_info *fs_info) { /* cancel requested || normal exit path */ return atomic_read(&fs_info->balance_cancel_req) || (atomic_read(&fs_info->balance_pause_req) == 0 && atomic_read(&fs_info->balance_cancel_req) == 0); } static void __cancel_balance(struct btrfs_fs_info *fs_info) { int ret; unset_balance_control(fs_info); ret = del_balance_item(fs_info->tree_root); BUG_ON(ret); } void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, struct btrfs_ioctl_balance_args *bargs); /* * Should be called with both balance and volume mutexes held */ int btrfs_balance(struct btrfs_balance_control *bctl, struct btrfs_ioctl_balance_args *bargs) { struct btrfs_fs_info *fs_info = bctl->fs_info; u64 allowed; int ret; if (btrfs_fs_closing(fs_info) || atomic_read(&fs_info->balance_pause_req) || atomic_read(&fs_info->balance_cancel_req)) { ret = -EINVAL; goto out; } /* * In case of mixed groups both data and meta should be picked, * and identical options should be given for both of them. */ allowed = btrfs_super_incompat_flags(fs_info->super_copy); if ((allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) && (bctl->flags & (BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA))) { if (!(bctl->flags & BTRFS_BALANCE_DATA) || !(bctl->flags & BTRFS_BALANCE_METADATA) || memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { printk(KERN_ERR "btrfs: with mixed groups data and " "metadata balance options must be the same\n"); ret = -EINVAL; goto out; } } /* * Profile changing sanity checks. Skip them if a simple * balance is requested. */ if (!((bctl->data.flags | bctl->sys.flags | bctl->meta.flags) & BTRFS_BALANCE_ARGS_CONVERT)) goto do_balance; allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; if (fs_info->fs_devices->num_devices == 1) allowed |= BTRFS_BLOCK_GROUP_DUP; else if (fs_info->fs_devices->num_devices < 4) allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1); else allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10); if (!profile_is_valid(bctl->data.target, 1) || bctl->data.target & ~allowed) { printk(KERN_ERR "btrfs: unable to start balance with target " "data profile %llu\n", (unsigned long long)bctl->data.target); ret = -EINVAL; goto out; } if (!profile_is_valid(bctl->meta.target, 1) || bctl->meta.target & ~allowed) { printk(KERN_ERR "btrfs: unable to start balance with target " "metadata profile %llu\n", (unsigned long long)bctl->meta.target); ret = -EINVAL; goto out; } if (!profile_is_valid(bctl->sys.target, 1) || bctl->sys.target & ~allowed) { printk(KERN_ERR "btrfs: unable to start balance with target " "system profile %llu\n", (unsigned long long)bctl->sys.target); ret = -EINVAL; goto out; } if (bctl->data.target & BTRFS_BLOCK_GROUP_DUP) { printk(KERN_ERR "btrfs: dup for data is not allowed\n"); ret = -EINVAL; goto out; } /* allow to reduce meta or sys integrity only if force set */ allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10; if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && (fs_info->avail_system_alloc_bits & allowed) && !(bctl->sys.target & allowed)) || ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && (fs_info->avail_metadata_alloc_bits & allowed) && !(bctl->meta.target & allowed))) { if (bctl->flags & BTRFS_BALANCE_FORCE) { printk(KERN_INFO "btrfs: force reducing metadata " "integrity\n"); } else { printk(KERN_ERR "btrfs: balance will reduce metadata " "integrity, use force if you want this\n"); ret = -EINVAL; goto out; } } do_balance: ret = insert_balance_item(fs_info->tree_root, bctl); if (ret && ret != -EEXIST) goto out; if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { BUG_ON(ret == -EEXIST); set_balance_control(bctl); } else { BUG_ON(ret != -EEXIST); spin_lock(&fs_info->balance_lock); update_balance_args(bctl); spin_unlock(&fs_info->balance_lock); } atomic_inc(&fs_info->balance_running); mutex_unlock(&fs_info->balance_mutex); ret = __btrfs_balance(fs_info); mutex_lock(&fs_info->balance_mutex); atomic_dec(&fs_info->balance_running); if (bargs) { memset(bargs, 0, sizeof(*bargs)); update_ioctl_balance_args(fs_info, 0, bargs); } if ((ret && ret != -ECANCELED && ret != -ENOSPC) || balance_need_close(fs_info)) { __cancel_balance(fs_info); } wake_up(&fs_info->balance_wait_q); return ret; out: if (bctl->flags & BTRFS_BALANCE_RESUME) __cancel_balance(fs_info); else kfree(bctl); return ret; } static int balance_kthread(void *data) { struct btrfs_balance_control *bctl = (struct btrfs_balance_control *)data; struct btrfs_fs_info *fs_info = bctl->fs_info; int ret = 0; mutex_lock(&fs_info->volume_mutex); mutex_lock(&fs_info->balance_mutex); set_balance_control(bctl); if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) { printk(KERN_INFO "btrfs: force skipping balance\n"); } else { printk(KERN_INFO "btrfs: continuing balance\n"); ret = btrfs_balance(bctl, NULL); } mutex_unlock(&fs_info->balance_mutex); mutex_unlock(&fs_info->volume_mutex); return ret; } int btrfs_recover_balance(struct btrfs_root *tree_root) { struct task_struct *tsk; struct btrfs_balance_control *bctl; struct btrfs_balance_item *item; struct btrfs_disk_balance_args disk_bargs; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; bctl = kzalloc(sizeof(*bctl), GFP_NOFS); if (!bctl) { ret = -ENOMEM; goto out; } key.objectid = BTRFS_BALANCE_OBJECTID; key.type = BTRFS_BALANCE_ITEM_KEY; key.offset = 0; ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0); if (ret < 0) goto out_bctl; if (ret > 0) { /* ret = -ENOENT; */ ret = 0; goto out_bctl; } leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); bctl->fs_info = tree_root->fs_info; bctl->flags = btrfs_balance_flags(leaf, item) | BTRFS_BALANCE_RESUME; btrfs_balance_data(leaf, item, &disk_bargs); btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); btrfs_balance_meta(leaf, item, &disk_bargs); btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); btrfs_balance_sys(leaf, item, &disk_bargs); btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); tsk = kthread_run(balance_kthread, bctl, "btrfs-balance"); if (IS_ERR(tsk)) ret = PTR_ERR(tsk); else goto out; out_bctl: kfree(bctl); out: btrfs_free_path(path); return ret; } int btrfs_pause_balance(struct btrfs_fs_info *fs_info) { int ret = 0; mutex_lock(&fs_info->balance_mutex); if (!fs_info->balance_ctl) { mutex_unlock(&fs_info->balance_mutex); return -ENOTCONN; } if (atomic_read(&fs_info->balance_running)) { atomic_inc(&fs_info->balance_pause_req); mutex_unlock(&fs_info->balance_mutex); wait_event(fs_info->balance_wait_q, atomic_read(&fs_info->balance_running) == 0); mutex_lock(&fs_info->balance_mutex); /* we are good with balance_ctl ripped off from under us */ BUG_ON(atomic_read(&fs_info->balance_running)); atomic_dec(&fs_info->balance_pause_req); } else { ret = -ENOTCONN; } mutex_unlock(&fs_info->balance_mutex); return ret; } int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) { mutex_lock(&fs_info->balance_mutex); if (!fs_info->balance_ctl) { mutex_unlock(&fs_info->balance_mutex); return -ENOTCONN; } atomic_inc(&fs_info->balance_cancel_req); /* * if we are running just wait and return, balance item is * deleted in btrfs_balance in this case */ if (atomic_read(&fs_info->balance_running)) { mutex_unlock(&fs_info->balance_mutex); wait_event(fs_info->balance_wait_q, atomic_read(&fs_info->balance_running) == 0); mutex_lock(&fs_info->balance_mutex); } else { /* __cancel_balance needs volume_mutex */ mutex_unlock(&fs_info->balance_mutex); mutex_lock(&fs_info->volume_mutex); mutex_lock(&fs_info->balance_mutex); if (fs_info->balance_ctl) __cancel_balance(fs_info); mutex_unlock(&fs_info->volume_mutex); } BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running)); atomic_dec(&fs_info->balance_cancel_req); mutex_unlock(&fs_info->balance_mutex); return 0; } /* * shrinking a device means finding all of the device extents past * the new size, and then following the back refs to the chunks. * The chunk relocation code actually frees the device extent */ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) { struct btrfs_trans_handle *trans; struct btrfs_root *root = device->dev_root; struct btrfs_dev_extent *dev_extent = NULL; struct btrfs_path *path; u64 length; u64 chunk_tree; u64 chunk_objectid; u64 chunk_offset; int ret; int slot; int failed = 0; bool retried = false; struct extent_buffer *l; struct btrfs_key key; struct btrfs_super_block *super_copy = root->fs_info->super_copy; u64 old_total = btrfs_super_total_bytes(super_copy); u64 old_size = device->total_bytes; u64 diff = device->total_bytes - new_size; if (new_size >= device->total_bytes) return -EINVAL; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = 2; lock_chunks(root); device->total_bytes = new_size; if (device->writeable) { device->fs_devices->total_rw_bytes -= diff; spin_lock(&root->fs_info->free_chunk_lock); root->fs_info->free_chunk_space -= diff; spin_unlock(&root->fs_info->free_chunk_lock); } unlock_chunks(root); again: key.objectid = device->devid; key.offset = (u64)-1; key.type = BTRFS_DEV_EXTENT_KEY; while (1) { ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto done; ret = btrfs_previous_item(root, path, 0, key.type); if (ret < 0) goto done; if (ret) { ret = 0; btrfs_release_path(path); break; } l = path->nodes[0]; slot = path->slots[0]; btrfs_item_key_to_cpu(l, &key, path->slots[0]); if (key.objectid != device->devid) { btrfs_release_path(path); break; } dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); length = btrfs_dev_extent_length(l, dev_extent); if (key.offset + length <= new_size) { btrfs_release_path(path); break; } chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); btrfs_release_path(path); ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, chunk_offset); if (ret && ret != -ENOSPC) goto done; if (ret == -ENOSPC) failed++; key.offset -= 1; } if (failed && !retried) { failed = 0; retried = true; goto again; } else if (failed && retried) { ret = -ENOSPC; lock_chunks(root); device->total_bytes = old_size; if (device->writeable) device->fs_devices->total_rw_bytes += diff; spin_lock(&root->fs_info->free_chunk_lock); root->fs_info->free_chunk_space += diff; spin_unlock(&root->fs_info->free_chunk_lock); unlock_chunks(root); goto done; } /* Shrinking succeeded, else we would be at "done". */ trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto done; } lock_chunks(root); device->disk_total_bytes = new_size; /* Now btrfs_update_device() will change the on-disk size. */ ret = btrfs_update_device(trans, device); if (ret) { unlock_chunks(root); btrfs_end_transaction(trans, root); goto done; } WARN_ON(diff > old_total); btrfs_set_super_total_bytes(super_copy, old_total - diff); unlock_chunks(root); btrfs_end_transaction(trans, root); done: btrfs_free_path(path); return ret; } static int btrfs_add_system_chunk(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; } /* * sort the devices in descending order by max_avail, total_avail */ static int btrfs_cmp_device_info(const void *a, const void *b) { const struct btrfs_device_info *di_a = a; const struct btrfs_device_info *di_b = b; if (di_a->max_avail > di_b->max_avail) return -1; if (di_a->max_avail < di_b->max_avail) return 1; if (di_a->total_avail > di_b->total_avail) return -1; if (di_a->total_avail < di_b->total_avail) return 1; return 0; } static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root, struct map_lookup **map_ret, u64 *num_bytes_out, u64 *stripe_size_out, u64 start, u64 type) { struct btrfs_fs_info *info = extent_root->fs_info; struct btrfs_fs_devices *fs_devices = info->fs_devices; struct list_head *cur; struct map_lookup *map = NULL; struct extent_map_tree *em_tree; struct extent_map *em; struct btrfs_device_info *devices_info = NULL; u64 total_avail; int num_stripes; /* total number of stripes to allocate */ int sub_stripes; /* sub_stripes info for map */ int dev_stripes; /* stripes per dev */ int devs_max; /* max devs to use */ int devs_min; /* min devs needed */ int devs_increment; /* ndevs has to be a multiple of this */ int ncopies; /* how many copies to data has */ int ret; u64 max_stripe_size; u64 max_chunk_size; u64 stripe_size; u64 num_bytes; int ndevs; int i; int j; if ((type & BTRFS_BLOCK_GROUP_RAID1) && (type & BTRFS_BLOCK_GROUP_DUP)) { WARN_ON(1); type &= ~BTRFS_BLOCK_GROUP_DUP; } if (list_empty(&fs_devices->alloc_list)) return -ENOSPC; sub_stripes = 1; dev_stripes = 1; devs_increment = 1; ncopies = 1; devs_max = 0; /* 0 == as many as possible */ devs_min = 1; /* * define the properties of each RAID type. * FIXME: move this to a global table and use it in all RAID * calculation code */ if (type & (BTRFS_BLOCK_GROUP_DUP)) { dev_stripes = 2; ncopies = 2; devs_max = 1; } else if (type & (BTRFS_BLOCK_GROUP_RAID0)) { devs_min = 2; } else if (type & (BTRFS_BLOCK_GROUP_RAID1)) { devs_increment = 2; ncopies = 2; devs_max = 2; devs_min = 2; } else if (type & (BTRFS_BLOCK_GROUP_RAID10)) { sub_stripes = 2; devs_increment = 2; ncopies = 2; devs_min = 4; } else { devs_max = 1; } if (type & BTRFS_BLOCK_GROUP_DATA) { max_stripe_size = 1024 * 1024 * 1024; max_chunk_size = 10 * max_stripe_size; } else if (type & BTRFS_BLOCK_GROUP_METADATA) { /* for larger filesystems, use larger metadata chunks */ if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024) max_stripe_size = 1024 * 1024 * 1024; else max_stripe_size = 256 * 1024 * 1024; max_chunk_size = max_stripe_size; } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { max_stripe_size = 32 * 1024 * 1024; max_chunk_size = 2 * max_stripe_size; } else { printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n", type); BUG_ON(1); } /* we don't want a chunk larger than 10% of writeable space */ max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1), max_chunk_size); devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices, GFP_NOFS); if (!devices_info) return -ENOMEM; cur = fs_devices->alloc_list.next; /* * in the first pass through the devices list, we gather information * about the available holes on each device. */ ndevs = 0; while (cur != &fs_devices->alloc_list) { struct btrfs_device *device; u64 max_avail; u64 dev_offset; device = list_entry(cur, struct btrfs_device, dev_alloc_list); cur = cur->next; if (!device->writeable) { printk(KERN_ERR "btrfs: read-only device in alloc_list\n"); WARN_ON(1); continue; } if (!device->in_fs_metadata) continue; if (device->total_bytes > device->bytes_used) total_avail = device->total_bytes - device->bytes_used; else total_avail = 0; /* If there is no space on this device, skip it. */ if (total_avail == 0) continue; ret = find_free_dev_extent(device, max_stripe_size * dev_stripes, &dev_offset, &max_avail); if (ret && ret != -ENOSPC) goto error; if (ret == 0) max_avail = max_stripe_size * dev_stripes; if (max_avail < BTRFS_STRIPE_LEN * dev_stripes) continue; devices_info[ndevs].dev_offset = dev_offset; devices_info[ndevs].max_avail = max_avail; devices_info[ndevs].total_avail = total_avail; devices_info[ndevs].dev = device; ++ndevs; } /* * now sort the devices by hole size / available space */ sort(devices_info, ndevs, sizeof(struct btrfs_device_info), btrfs_cmp_device_info, NULL); /* round down to number of usable stripes */ ndevs -= ndevs % devs_increment; if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) { ret = -ENOSPC; goto error; } if (devs_max && ndevs > devs_max) ndevs = devs_max; /* * the primary goal is to maximize the number of stripes, so use as many * devices as possible, even if the stripes are not maximum sized. */ stripe_size = devices_info[ndevs-1].max_avail; num_stripes = ndevs * dev_stripes; if (stripe_size * num_stripes > max_chunk_size * ncopies) { stripe_size = max_chunk_size * ncopies; do_div(stripe_size, num_stripes); } do_div(stripe_size, dev_stripes); do_div(stripe_size, BTRFS_STRIPE_LEN); stripe_size *= BTRFS_STRIPE_LEN; map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); if (!map) { ret = -ENOMEM; goto error; } map->num_stripes = num_stripes; for (i = 0; i < ndevs; ++i) { for (j = 0; j < dev_stripes; ++j) { int s = i * dev_stripes + j; map->stripes[s].dev = devices_info[i].dev; map->stripes[s].physical = devices_info[i].dev_offset + j * stripe_size; } } map->sector_size = extent_root->sectorsize; map->stripe_len = BTRFS_STRIPE_LEN; map->io_align = BTRFS_STRIPE_LEN; map->io_width = BTRFS_STRIPE_LEN; map->type = type; map->sub_stripes = sub_stripes; *map_ret = map; num_bytes = stripe_size * (num_stripes / ncopies); *stripe_size_out = stripe_size; *num_bytes_out = num_bytes; trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes); em = alloc_extent_map(); if (!em) { ret = -ENOMEM; goto error; } em->bdev = (struct block_device *)map; em->start = start; em->len = num_bytes; em->block_start = 0; em->block_len = em->len; em_tree = &extent_root->fs_info->mapping_tree.map_tree; write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); write_unlock(&em_tree->lock); BUG_ON(ret); free_extent_map(em); ret = btrfs_make_block_group(trans, extent_root, 0, type, BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes); BUG_ON(ret); for (i = 0; i < map->num_stripes; ++i) { struct btrfs_device *device; u64 dev_offset; device = map->stripes[i].dev; dev_offset = map->stripes[i].physical; ret = btrfs_alloc_dev_extent(trans, device, info->chunk_root->root_key.objectid, BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, dev_offset, stripe_size); BUG_ON(ret); } kfree(devices_info); return 0; error: kfree(map); kfree(devices_info); return ret; } static int __finish_chunk_alloc(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root, struct map_lookup *map, u64 chunk_offset, u64 chunk_size, u64 stripe_size) { u64 dev_offset; struct btrfs_key key; struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; struct btrfs_device *device; struct btrfs_chunk *chunk; struct btrfs_stripe *stripe; size_t item_size = btrfs_chunk_item_size(map->num_stripes); int index = 0; int ret; chunk = kzalloc(item_size, GFP_NOFS); if (!chunk) return -ENOMEM; index = 0; while (index < map->num_stripes) { device = map->stripes[index].dev; device->bytes_used += stripe_size; ret = btrfs_update_device(trans, device); BUG_ON(ret); index++; } spin_lock(&extent_root->fs_info->free_chunk_lock); extent_root->fs_info->free_chunk_space -= (stripe_size * map->num_stripes); spin_unlock(&extent_root->fs_info->free_chunk_lock); index = 0; stripe = &chunk->stripe; while (index < map->num_stripes) { device = map->stripes[index].dev; dev_offset = map->stripes[index].physical; 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); stripe++; index++; } btrfs_set_stack_chunk_length(chunk, chunk_size); btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); btrfs_set_stack_chunk_type(chunk, map->type); btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.type = BTRFS_CHUNK_ITEM_KEY; key.offset = chunk_offset; ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); BUG_ON(ret); if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { ret = btrfs_add_system_chunk(chunk_root, &key, chunk, item_size); BUG_ON(ret); } kfree(chunk); return 0; } /* * Chunk allocation falls into two parts. The first part does works * that make the new allocated chunk useable, but not do any operation * that modifies the chunk tree. The second part does the works that * require modifying the chunk tree. This division is important for the * bootstrap process of adding storage to a seed btrfs. */ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root, u64 type) { u64 chunk_offset; u64 chunk_size; u64 stripe_size; struct map_lookup *map; struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; int ret; ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset); if (ret) return ret; ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, &stripe_size, chunk_offset, type); if (ret) return ret; ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, chunk_size, stripe_size); BUG_ON(ret); return 0; } static noinline int init_first_rw_device(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_device *device) { u64 chunk_offset; u64 sys_chunk_offset; u64 chunk_size; u64 sys_chunk_size; u64 stripe_size; u64 sys_stripe_size; u64 alloc_profile; struct map_lookup *map; struct map_lookup *sys_map; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_root *extent_root = fs_info->extent_root; int ret; ret = find_next_chunk(fs_info->chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset); if (ret) return ret; alloc_profile = BTRFS_BLOCK_GROUP_METADATA | fs_info->avail_metadata_alloc_bits; alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile); ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, &stripe_size, chunk_offset, alloc_profile); BUG_ON(ret); sys_chunk_offset = chunk_offset + chunk_size; alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM | fs_info->avail_system_alloc_bits; alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile); ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map, &sys_chunk_size, &sys_stripe_size, sys_chunk_offset, alloc_profile); BUG_ON(ret); ret = btrfs_add_device(trans, fs_info->chunk_root, device); BUG_ON(ret); /* * Modifying chunk tree needs allocating new blocks from both * system block group and metadata block group. So we only can * do operations require modifying the chunk tree after both * block groups were created. */ ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, chunk_size, stripe_size); BUG_ON(ret); ret = __finish_chunk_alloc(trans, extent_root, sys_map, sys_chunk_offset, sys_chunk_size, sys_stripe_size); BUG_ON(ret); return 0; } int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) { struct extent_map *em; struct map_lookup *map; struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; int readonly = 0; int i; read_lock(&map_tree->map_tree.lock); em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); read_unlock(&map_tree->map_tree.lock); if (!em) return 1; if (btrfs_test_opt(root, DEGRADED)) { free_extent_map(em); return 0; } map = (struct map_lookup *)em->bdev; for (i = 0; i < map->num_stripes; i++) { if (!map->stripes[i].dev->writeable) { readonly = 1; break; } } free_extent_map(em); return readonly; } void btrfs_mapping_init(struct btrfs_mapping_tree *tree) { extent_map_tree_init(&tree->map_tree); } void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree) { struct extent_map *em; while (1) { write_lock(&tree->map_tree.lock); em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1); if (em) remove_extent_mapping(&tree->map_tree, em); write_unlock(&tree->map_tree.lock); if (!em) break; kfree(em->bdev); /* once for us */ free_extent_map(em); /* once for the tree */ free_extent_map(em); } } int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len) { struct extent_map *em; struct map_lookup *map; struct extent_map_tree *em_tree = &map_tree->map_tree; int ret; read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, logical, len); read_unlock(&em_tree->lock); BUG_ON(!em); BUG_ON(em->start > logical || em->start + em->len < logical); map = (struct map_lookup *)em->bdev; 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; free_extent_map(em); return ret; } static int find_live_mirror(struct map_lookup *map, int first, int num, int optimal) { int i; if (map->stripes[optimal].dev->bdev) return optimal; for (i = first; i < first + num; i++) { if (map->stripes[i].dev->bdev) return i; } /* we couldn't find one that doesn't fail. Just return something * and the io error handling code will clean up eventually */ return optimal; } static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, u64 logical, u64 *length, struct btrfs_bio **bbio_ret, int mirror_num) { struct extent_map *em; struct map_lookup *map; struct extent_map_tree *em_tree = &map_tree->map_tree; u64 offset; u64 stripe_offset; u64 stripe_end_offset; u64 stripe_nr; u64 stripe_nr_orig; u64 stripe_nr_end; int stripe_index; int i; int ret = 0; int num_stripes; int max_errors = 0; struct btrfs_bio *bbio = NULL; read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, logical, *length); read_unlock(&em_tree->lock); if (!em) { printk(KERN_CRIT "unable to find logical %llu len %llu\n", (unsigned long long)logical, (unsigned long long)*length); BUG(); } BUG_ON(em->start > logical || em->start + em->len < logical); map = (struct map_lookup *)em->bdev; offset = logical - em->start; if (mirror_num > map->num_stripes) mirror_num = 0; stripe_nr = offset; /* * stripe_nr counts the total number of stripes we have to stride * to get to this block */ do_div(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 (rw & REQ_DISCARD) *length = min_t(u64, em->len - offset, *length); else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { /* we limit the length of each bio to what fits in a stripe */ *length = min_t(u64, em->len - offset, map->stripe_len - stripe_offset); } else { *length = em->len - offset; } if (!bbio_ret) goto out; num_stripes = 1; stripe_index = 0; stripe_nr_orig = stripe_nr; stripe_nr_end = (offset + *length + map->stripe_len - 1) & (~(map->stripe_len - 1)); do_div(stripe_nr_end, map->stripe_len); stripe_end_offset = stripe_nr_end * map->stripe_len - (offset + *length); if (map->type & BTRFS_BLOCK_GROUP_RAID0) { if (rw & REQ_DISCARD) num_stripes = min_t(u64, map->num_stripes, stripe_nr_end - stripe_nr_orig); stripe_index = do_div(stripe_nr, map->num_stripes); } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { if (rw & (REQ_WRITE | REQ_DISCARD)) num_stripes = map->num_stripes; else if (mirror_num) stripe_index = mirror_num - 1; else { stripe_index = find_live_mirror(map, 0, map->num_stripes, current->pid % map->num_stripes); mirror_num = stripe_index + 1; } } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { if (rw & (REQ_WRITE | REQ_DISCARD)) { num_stripes = map->num_stripes; } else if (mirror_num) { stripe_index = mirror_num - 1; } else { mirror_num = 1; } } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { int factor = map->num_stripes / map->sub_stripes; stripe_index = do_div(stripe_nr, factor); stripe_index *= map->sub_stripes; if (rw & REQ_WRITE) num_stripes = map->sub_stripes; else if (rw & REQ_DISCARD) num_stripes = min_t(u64, map->sub_stripes * (stripe_nr_end - stripe_nr_orig), map->num_stripes); else if (mirror_num) stripe_index += mirror_num - 1; else { stripe_index = find_live_mirror(map, stripe_index, map->sub_stripes, stripe_index + current->pid % map->sub_stripes); mirror_num = stripe_index + 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 = do_div(stripe_nr, map->num_stripes); mirror_num = stripe_index + 1; } BUG_ON(stripe_index >= map->num_stripes); bbio = kzalloc(btrfs_bio_size(num_stripes), GFP_NOFS); if (!bbio) { ret = -ENOMEM; goto out; } atomic_set(&bbio->error, 0); if (rw & REQ_DISCARD) { int factor = 0; int sub_stripes = 0; u64 stripes_per_dev = 0; u32 remaining_stripes = 0; if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { if (map->type & BTRFS_BLOCK_GROUP_RAID0) sub_stripes = 1; else sub_stripes = map->sub_stripes; factor = map->num_stripes / sub_stripes; stripes_per_dev = div_u64_rem(stripe_nr_end - stripe_nr_orig, factor, &remaining_stripes); } for (i = 0; i < num_stripes; i++) { bbio->stripes[i].physical = map->stripes[stripe_index].physical + stripe_offset + stripe_nr * map->stripe_len; bbio->stripes[i].dev = map->stripes[stripe_index].dev; if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { bbio->stripes[i].length = stripes_per_dev * map->stripe_len; if (i / sub_stripes < remaining_stripes) bbio->stripes[i].length += map->stripe_len; if (i < sub_stripes) bbio->stripes[i].length -= stripe_offset; if ((i / sub_stripes + 1) % sub_stripes == remaining_stripes) bbio->stripes[i].length -= stripe_end_offset; if (i == sub_stripes - 1) stripe_offset = 0; } else bbio->stripes[i].length = *length; stripe_index++; if (stripe_index == map->num_stripes) { /* This could only happen for RAID0/10 */ stripe_index = 0; stripe_nr++; } } } else { for (i = 0; i < num_stripes; i++) { bbio->stripes[i].physical = map->stripes[stripe_index].physical + stripe_offset + stripe_nr * map->stripe_len; bbio->stripes[i].dev = map->stripes[stripe_index].dev; stripe_index++; } } if (rw & REQ_WRITE) { if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10 | BTRFS_BLOCK_GROUP_DUP)) { max_errors = 1; } } *bbio_ret = bbio; bbio->num_stripes = num_stripes; bbio->max_errors = max_errors; bbio->mirror_num = mirror_num; out: free_extent_map(em); return ret; } int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, u64 logical, u64 *length, struct btrfs_bio **bbio_ret, int mirror_num) { return __btrfs_map_block(map_tree, rw, logical, length, bbio_ret, mirror_num); } 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 extent_map_tree *em_tree = &map_tree->map_tree; struct extent_map *em; struct map_lookup *map; u64 *buf; u64 bytenr; u64 length; u64 stripe_nr; int i, j, nr = 0; read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, chunk_start, 1); read_unlock(&em_tree->lock); BUG_ON(!em || em->start != chunk_start); map = (struct map_lookup *)em->bdev; length = em->len; if (map->type & BTRFS_BLOCK_GROUP_RAID10) do_div(length, map->num_stripes / map->sub_stripes); else if (map->type & BTRFS_BLOCK_GROUP_RAID0) do_div(length, map->num_stripes); buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); BUG_ON(!buf); 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; do_div(stripe_nr, map->stripe_len); if (map->type & BTRFS_BLOCK_GROUP_RAID10) { stripe_nr = stripe_nr * map->num_stripes + i; do_div(stripe_nr, map->sub_stripes); } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { stripe_nr = stripe_nr * map->num_stripes + i; } bytenr = chunk_start + stripe_nr * map->stripe_len; WARN_ON(nr >= map->num_stripes); for (j = 0; j < nr; j++) { if (buf[j] == bytenr) break; } if (j == nr) { WARN_ON(nr >= map->num_stripes); buf[nr++] = bytenr; } } *logical = buf; *naddrs = nr; *stripe_len = map->stripe_len; free_extent_map(em); return 0; } static void btrfs_end_bio(struct bio *bio, int err) { struct btrfs_bio *bbio = bio->bi_private; int is_orig_bio = 0; if (err) atomic_inc(&bbio->error); if (bio == bbio->orig_bio) is_orig_bio = 1; if (atomic_dec_and_test(&bbio->stripes_pending)) { if (!is_orig_bio) { bio_put(bio); bio = bbio->orig_bio; } bio->bi_private = bbio->private; bio->bi_end_io = bbio->end_io; bio->bi_bdev = (struct block_device *) (unsigned long)bbio->mirror_num; /* only send an error to the higher layers if it is * beyond the tolerance of the multi-bio */ if (atomic_read(&bbio->error) > bbio->max_errors) { err = -EIO; } else { /* * this bio is actually up to date, we didn't * go over the max number of errors */ set_bit(BIO_UPTODATE, &bio->bi_flags); err = 0; } kfree(bbio); bio_endio(bio, err); } else if (!is_orig_bio) { bio_put(bio); } } struct async_sched { struct bio *bio; int rw; struct btrfs_fs_info *info; struct btrfs_work work; }; /* * see run_scheduled_bios for a description of why bios are collected for * async submit. * * This will add one bio to the pending list for a device and make sure * the work struct is scheduled. */ static noinline int schedule_bio(struct btrfs_root *root, struct btrfs_device *device, int rw, struct bio *bio) { int should_queue = 1; struct btrfs_pending_bios *pending_bios; /* don't bother with additional async steps for reads, right now */ if (!(rw & REQ_WRITE)) { bio_get(bio); btrfsic_submit_bio(rw, bio); bio_put(bio); return 0; } /* * nr_async_bios allows us to reliably return congestion to the * higher layers. Otherwise, the async bio makes it appear we have * made progress against dirty pages when we've really just put it * on a queue for later */ atomic_inc(&root->fs_info->nr_async_bios); WARN_ON(bio->bi_next); bio->bi_next = NULL; bio->bi_rw |= rw; spin_lock(&device->io_lock); if (bio->bi_rw & REQ_SYNC) pending_bios = &device->pending_sync_bios; else pending_bios = &device->pending_bios; if (pending_bios->tail) pending_bios->tail->bi_next = bio; pending_bios->tail = bio; if (!pending_bios->head) pending_bios->head = bio; if (device->running_pending) should_queue = 0; spin_unlock(&device->io_lock); if (should_queue) btrfs_queue_worker(&root->fs_info->submit_workers, &device->work); return 0; } int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, int mirror_num, int async_submit) { struct btrfs_mapping_tree *map_tree; struct btrfs_device *dev; struct bio *first_bio = bio; u64 logical = (u64)bio->bi_sector << 9; u64 length = 0; u64 map_length; int ret; int dev_nr = 0; int total_devs = 1; struct btrfs_bio *bbio = NULL; length = bio->bi_size; map_tree = &root->fs_info->mapping_tree; map_length = length; ret = btrfs_map_block(map_tree, rw, logical, &map_length, &bbio, mirror_num); BUG_ON(ret); total_devs = bbio->num_stripes; if (map_length < length) { printk(KERN_CRIT "mapping failed logical %llu bio len %llu " "len %llu\n", (unsigned long long)logical, (unsigned long long)length, (unsigned long long)map_length); BUG(); } bbio->orig_bio = first_bio; bbio->private = first_bio->bi_private; bbio->end_io = first_bio->bi_end_io; atomic_set(&bbio->stripes_pending, bbio->num_stripes); while (dev_nr < total_devs) { if (dev_nr < total_devs - 1) { bio = bio_clone(first_bio, GFP_NOFS); BUG_ON(!bio); } else { bio = first_bio; } bio->bi_private = bbio; bio->bi_end_io = btrfs_end_bio; bio->bi_sector = bbio->stripes[dev_nr].physical >> 9; dev = bbio->stripes[dev_nr].dev; if (dev && dev->bdev && (rw != WRITE || dev->writeable)) { pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu " "(%s id %llu), size=%u\n", rw, (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, dev->name, dev->devid, bio->bi_size); bio->bi_bdev = dev->bdev; if (async_submit) schedule_bio(root, dev, rw, bio); else btrfsic_submit_bio(rw, bio); } else { bio->bi_bdev = root->fs_info->fs_devices->latest_bdev; bio->bi_sector = logical >> 9; bio_endio(bio, -EIO); } dev_nr++; } 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; } static struct btrfs_device *add_missing_dev(struct btrfs_root *root, u64 devid, u8 *dev_uuid) { struct btrfs_device *device; struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; device = kzalloc(sizeof(*device), GFP_NOFS); if (!device) return NULL; list_add(&device->dev_list, &fs_devices->devices); device->dev_root = root->fs_info->dev_root; device->devid = devid; device->work.func = pending_bios_fn; device->fs_devices = fs_devices; device->missing = 1; fs_devices->num_devices++; fs_devices->missing_devices++; spin_lock_init(&device->io_lock); INIT_LIST_HEAD(&device->dev_alloc_list); memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE); 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 extent_map *em; 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); read_lock(&map_tree->map_tree.lock); em = lookup_extent_mapping(&map_tree->map_tree, logical, 1); read_unlock(&map_tree->map_tree.lock); /* already mapped? */ if (em && em->start <= logical && em->start + em->len > logical) { free_extent_map(em); return 0; } else if (em) { free_extent_map(em); } em = alloc_extent_map(); if (!em) return -ENOMEM; num_stripes = btrfs_chunk_num_stripes(leaf, chunk); map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); if (!map) { free_extent_map(em); return -ENOMEM; } em->bdev = (struct block_device *)map; em->start = logical; em->len = length; em->block_start = 0; em->block_len = em->len; 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 && !btrfs_test_opt(root, DEGRADED)) { kfree(map); free_extent_map(em); return -EIO; } if (!map->stripes[i].dev) { map->stripes[i].dev = add_missing_dev(root, devid, uuid); if (!map->stripes[i].dev) { kfree(map); free_extent_map(em); return -EIO; } } map->stripes[i].dev->in_fs_metadata = 1; } write_lock(&map_tree->map_tree.lock); ret = add_extent_mapping(&map_tree->map_tree, em); write_unlock(&map_tree->map_tree.lock); BUG_ON(ret); free_extent_map(em); 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->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); device->total_bytes = device->disk_total_bytes; 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; BUG_ON(!mutex_is_locked(&uuid_mutex)); 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; } fs_devices = clone_fs_devices(fs_devices); if (IS_ERR(fs_devices)) { ret = PTR_ERR(fs_devices); goto out; } ret = __btrfs_open_devices(fs_devices, FMODE_READ, root->fs_info->bdev_holder); if (ret) goto out; if (!fs_devices->seeding) { __btrfs_close_devices(fs_devices); free_fs_devices(fs_devices); ret = -EINVAL; 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; 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 && !btrfs_test_opt(root, DEGRADED)) return ret; } device = btrfs_find_device(root, devid, dev_uuid, fs_uuid); if (!device || !device->bdev) { if (!btrfs_test_opt(root, DEGRADED)) return -EIO; if (!device) { printk(KERN_WARNING "warning devid %llu missing\n", (unsigned long long)devid); device = add_missing_dev(root, devid, dev_uuid); if (!device) return -ENOMEM; } else if (!device->missing) { /* * this happens when a device that was properly setup * in the device info lists suddenly goes bad. * device->bdev is NULL, and so we have to set * device->missing to one here */ root->fs_info->fs_devices->missing_devices++; device->missing = 1; } } if (device->fs_devices != root->fs_info->fs_devices) { BUG_ON(device->writeable); if (device->generation != btrfs_device_generation(leaf, dev_item)) return -EINVAL; } fill_device_from_item(leaf, dev_item, device); device->dev_root = root->fs_info->dev_root; device->in_fs_metadata = 1; if (device->writeable) { device->fs_devices->total_rw_bytes += device->total_bytes; spin_lock(&root->fs_info->free_chunk_lock); root->fs_info->free_chunk_space += device->total_bytes - device->bytes_used; spin_unlock(&root->fs_info->free_chunk_lock); } ret = 0; 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 *ptr; unsigned long sb_ptr; int ret = 0; u32 num_stripes; u32 array_size; u32 len = 0; u32 cur; struct btrfs_key key; sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET, BTRFS_SUPER_INFO_SIZE); if (!sb) return -ENOMEM; btrfs_set_buffer_uptodate(sb); btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); array_size = btrfs_super_sys_array_size(super_copy); 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 { ret = -EIO; break; } 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; mutex_lock(&uuid_mutex); lock_chunks(root); /* 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); 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 (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); if (ret) goto error; } } 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); if (ret) goto error; } path->slots[0]++; } if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { key.objectid = 0; btrfs_release_path(path); goto again; } ret = 0; error: unlock_chunks(root); mutex_unlock(&uuid_mutex); btrfs_free_path(path); return ret; }