From e3e0520b32bc3dbc64110536d171bfb334ac7a2a Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 20 Jun 2019 15:37:55 -0400 Subject: [PATCH] btrfs: migrate the block group removal code This is the removal code and the unused bgs code. Signed-off-by: Josef Bacik Reviewed-by: David Sterba [ refresh, move clear_incompat_bg_bits ] Signed-off-by: David Sterba --- fs/btrfs/block-group.c | 540 +++++++++++++++++++++++++++++++++++++++++ fs/btrfs/block-group.h | 7 + fs/btrfs/ctree.h | 7 - fs/btrfs/extent-tree.c | 537 ---------------------------------------- 4 files changed, 547 insertions(+), 544 deletions(-) diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 643a2f16603b..a27f814b86bd 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -6,6 +6,10 @@ #include "disk-io.h" #include "free-space-cache.h" #include "free-space-tree.h" +#include "disk-io.h" +#include "volumes.h" +#include "transaction.h" +#include "ref-verify.h" void btrfs_get_block_group(struct btrfs_block_group_cache *cache) { @@ -660,3 +664,539 @@ int btrfs_cache_block_group(struct btrfs_block_group_cache *cache, return ret; } + +static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) +{ + u64 extra_flags = chunk_to_extended(flags) & + BTRFS_EXTENDED_PROFILE_MASK; + + write_seqlock(&fs_info->profiles_lock); + if (flags & BTRFS_BLOCK_GROUP_DATA) + fs_info->avail_data_alloc_bits &= ~extra_flags; + if (flags & BTRFS_BLOCK_GROUP_METADATA) + fs_info->avail_metadata_alloc_bits &= ~extra_flags; + if (flags & BTRFS_BLOCK_GROUP_SYSTEM) + fs_info->avail_system_alloc_bits &= ~extra_flags; + write_sequnlock(&fs_info->profiles_lock); +} + +/* + * Clear incompat bits for the following feature(s): + * + * - RAID56 - in case there's neither RAID5 nor RAID6 profile block group + * in the whole filesystem + */ +static void clear_incompat_bg_bits(struct btrfs_fs_info *fs_info, u64 flags) +{ + if (flags & BTRFS_BLOCK_GROUP_RAID56_MASK) { + struct list_head *head = &fs_info->space_info; + struct btrfs_space_info *sinfo; + + list_for_each_entry_rcu(sinfo, head, list) { + bool found = false; + + down_read(&sinfo->groups_sem); + if (!list_empty(&sinfo->block_groups[BTRFS_RAID_RAID5])) + found = true; + if (!list_empty(&sinfo->block_groups[BTRFS_RAID_RAID6])) + found = true; + up_read(&sinfo->groups_sem); + + if (found) + return; + } + btrfs_clear_fs_incompat(fs_info, RAID56); + } +} + +int btrfs_remove_block_group(struct btrfs_trans_handle *trans, + u64 group_start, struct extent_map *em) +{ + struct btrfs_fs_info *fs_info = trans->fs_info; + struct btrfs_root *root = fs_info->extent_root; + struct btrfs_path *path; + struct btrfs_block_group_cache *block_group; + struct btrfs_free_cluster *cluster; + struct btrfs_root *tree_root = fs_info->tree_root; + struct btrfs_key key; + struct inode *inode; + struct kobject *kobj = NULL; + int ret; + int index; + int factor; + struct btrfs_caching_control *caching_ctl = NULL; + bool remove_em; + bool remove_rsv = false; + + block_group = btrfs_lookup_block_group(fs_info, group_start); + BUG_ON(!block_group); + BUG_ON(!block_group->ro); + + trace_btrfs_remove_block_group(block_group); + /* + * Free the reserved super bytes from this block group before + * remove it. + */ + btrfs_free_excluded_extents(block_group); + btrfs_free_ref_tree_range(fs_info, block_group->key.objectid, + block_group->key.offset); + + memcpy(&key, &block_group->key, sizeof(key)); + index = btrfs_bg_flags_to_raid_index(block_group->flags); + factor = btrfs_bg_type_to_factor(block_group->flags); + + /* make sure this block group isn't part of an allocation cluster */ + cluster = &fs_info->data_alloc_cluster; + spin_lock(&cluster->refill_lock); + btrfs_return_cluster_to_free_space(block_group, cluster); + spin_unlock(&cluster->refill_lock); + + /* + * make sure this block group isn't part of a metadata + * allocation cluster + */ + cluster = &fs_info->meta_alloc_cluster; + spin_lock(&cluster->refill_lock); + btrfs_return_cluster_to_free_space(block_group, cluster); + spin_unlock(&cluster->refill_lock); + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + /* + * get the inode first so any iput calls done for the io_list + * aren't the final iput (no unlinks allowed now) + */ + inode = lookup_free_space_inode(block_group, path); + + mutex_lock(&trans->transaction->cache_write_mutex); + /* + * Make sure our free space cache IO is done before removing the + * free space inode + */ + spin_lock(&trans->transaction->dirty_bgs_lock); + if (!list_empty(&block_group->io_list)) { + list_del_init(&block_group->io_list); + + WARN_ON(!IS_ERR(inode) && inode != block_group->io_ctl.inode); + + spin_unlock(&trans->transaction->dirty_bgs_lock); + btrfs_wait_cache_io(trans, block_group, path); + btrfs_put_block_group(block_group); + spin_lock(&trans->transaction->dirty_bgs_lock); + } + + if (!list_empty(&block_group->dirty_list)) { + list_del_init(&block_group->dirty_list); + remove_rsv = true; + btrfs_put_block_group(block_group); + } + spin_unlock(&trans->transaction->dirty_bgs_lock); + mutex_unlock(&trans->transaction->cache_write_mutex); + + if (!IS_ERR(inode)) { + ret = btrfs_orphan_add(trans, BTRFS_I(inode)); + if (ret) { + btrfs_add_delayed_iput(inode); + goto out; + } + clear_nlink(inode); + /* One for the block groups ref */ + spin_lock(&block_group->lock); + if (block_group->iref) { + block_group->iref = 0; + block_group->inode = NULL; + spin_unlock(&block_group->lock); + iput(inode); + } else { + spin_unlock(&block_group->lock); + } + /* One for our lookup ref */ + btrfs_add_delayed_iput(inode); + } + + key.objectid = BTRFS_FREE_SPACE_OBJECTID; + key.offset = block_group->key.objectid; + key.type = 0; + + ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1); + if (ret < 0) + goto out; + if (ret > 0) + btrfs_release_path(path); + if (ret == 0) { + ret = btrfs_del_item(trans, tree_root, path); + if (ret) + goto out; + btrfs_release_path(path); + } + + spin_lock(&fs_info->block_group_cache_lock); + rb_erase(&block_group->cache_node, + &fs_info->block_group_cache_tree); + RB_CLEAR_NODE(&block_group->cache_node); + + if (fs_info->first_logical_byte == block_group->key.objectid) + fs_info->first_logical_byte = (u64)-1; + spin_unlock(&fs_info->block_group_cache_lock); + + down_write(&block_group->space_info->groups_sem); + /* + * we must use list_del_init so people can check to see if they + * are still on the list after taking the semaphore + */ + list_del_init(&block_group->list); + if (list_empty(&block_group->space_info->block_groups[index])) { + kobj = block_group->space_info->block_group_kobjs[index]; + block_group->space_info->block_group_kobjs[index] = NULL; + clear_avail_alloc_bits(fs_info, block_group->flags); + } + up_write(&block_group->space_info->groups_sem); + clear_incompat_bg_bits(fs_info, block_group->flags); + if (kobj) { + kobject_del(kobj); + kobject_put(kobj); + } + + if (block_group->has_caching_ctl) + caching_ctl = btrfs_get_caching_control(block_group); + if (block_group->cached == BTRFS_CACHE_STARTED) + btrfs_wait_block_group_cache_done(block_group); + if (block_group->has_caching_ctl) { + down_write(&fs_info->commit_root_sem); + if (!caching_ctl) { + struct btrfs_caching_control *ctl; + + list_for_each_entry(ctl, + &fs_info->caching_block_groups, list) + if (ctl->block_group == block_group) { + caching_ctl = ctl; + refcount_inc(&caching_ctl->count); + break; + } + } + if (caching_ctl) + list_del_init(&caching_ctl->list); + up_write(&fs_info->commit_root_sem); + if (caching_ctl) { + /* Once for the caching bgs list and once for us. */ + btrfs_put_caching_control(caching_ctl); + btrfs_put_caching_control(caching_ctl); + } + } + + spin_lock(&trans->transaction->dirty_bgs_lock); + WARN_ON(!list_empty(&block_group->dirty_list)); + WARN_ON(!list_empty(&block_group->io_list)); + spin_unlock(&trans->transaction->dirty_bgs_lock); + + btrfs_remove_free_space_cache(block_group); + + spin_lock(&block_group->space_info->lock); + list_del_init(&block_group->ro_list); + + if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) { + WARN_ON(block_group->space_info->total_bytes + < block_group->key.offset); + WARN_ON(block_group->space_info->bytes_readonly + < block_group->key.offset); + WARN_ON(block_group->space_info->disk_total + < block_group->key.offset * factor); + } + block_group->space_info->total_bytes -= block_group->key.offset; + block_group->space_info->bytes_readonly -= block_group->key.offset; + block_group->space_info->disk_total -= block_group->key.offset * factor; + + spin_unlock(&block_group->space_info->lock); + + memcpy(&key, &block_group->key, sizeof(key)); + + mutex_lock(&fs_info->chunk_mutex); + spin_lock(&block_group->lock); + block_group->removed = 1; + /* + * At this point trimming can't start on this block group, because we + * removed the block group from the tree fs_info->block_group_cache_tree + * so no one can't find it anymore and even if someone already got this + * block group before we removed it from the rbtree, they have already + * incremented block_group->trimming - if they didn't, they won't find + * any free space entries because we already removed them all when we + * called btrfs_remove_free_space_cache(). + * + * And we must not remove the extent map from the fs_info->mapping_tree + * to prevent the same logical address range and physical device space + * ranges from being reused for a new block group. This is because our + * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is + * completely transactionless, so while it is trimming a range the + * currently running transaction might finish and a new one start, + * allowing for new block groups to be created that can reuse the same + * physical device locations unless we take this special care. + * + * There may also be an implicit trim operation if the file system + * is mounted with -odiscard. The same protections must remain + * in place until the extents have been discarded completely when + * the transaction commit has completed. + */ + remove_em = (atomic_read(&block_group->trimming) == 0); + spin_unlock(&block_group->lock); + + mutex_unlock(&fs_info->chunk_mutex); + + ret = remove_block_group_free_space(trans, block_group); + if (ret) + goto out; + + btrfs_put_block_group(block_group); + btrfs_put_block_group(block_group); + + ret = btrfs_search_slot(trans, root, &key, path, -1, 1); + if (ret > 0) + ret = -EIO; + if (ret < 0) + goto out; + + ret = btrfs_del_item(trans, root, path); + if (ret) + goto out; + + if (remove_em) { + struct extent_map_tree *em_tree; + + em_tree = &fs_info->mapping_tree; + write_lock(&em_tree->lock); + remove_extent_mapping(em_tree, em); + write_unlock(&em_tree->lock); + /* once for the tree */ + free_extent_map(em); + } +out: + if (remove_rsv) + btrfs_delayed_refs_rsv_release(fs_info, 1); + btrfs_free_path(path); + return ret; +} + +struct btrfs_trans_handle *btrfs_start_trans_remove_block_group( + struct btrfs_fs_info *fs_info, const u64 chunk_offset) +{ + struct extent_map_tree *em_tree = &fs_info->mapping_tree; + struct extent_map *em; + struct map_lookup *map; + unsigned int num_items; + + read_lock(&em_tree->lock); + em = lookup_extent_mapping(em_tree, chunk_offset, 1); + read_unlock(&em_tree->lock); + ASSERT(em && em->start == chunk_offset); + + /* + * We need to reserve 3 + N units from the metadata space info in order + * to remove a block group (done at btrfs_remove_chunk() and at + * btrfs_remove_block_group()), which are used for: + * + * 1 unit for adding the free space inode's orphan (located in the tree + * of tree roots). + * 1 unit for deleting the block group item (located in the extent + * tree). + * 1 unit for deleting the free space item (located in tree of tree + * roots). + * N units for deleting N device extent items corresponding to each + * stripe (located in the device tree). + * + * In order to remove a block group we also need to reserve units in the + * system space info in order to update the chunk tree (update one or + * more device items and remove one chunk item), but this is done at + * btrfs_remove_chunk() through a call to check_system_chunk(). + */ + map = em->map_lookup; + num_items = 3 + map->num_stripes; + free_extent_map(em); + + return btrfs_start_transaction_fallback_global_rsv(fs_info->extent_root, + num_items, 1); +} + +/* + * Process the unused_bgs list and remove any that don't have any allocated + * space inside of them. + */ +void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) +{ + struct btrfs_block_group_cache *block_group; + struct btrfs_space_info *space_info; + struct btrfs_trans_handle *trans; + int ret = 0; + + if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags)) + return; + + spin_lock(&fs_info->unused_bgs_lock); + while (!list_empty(&fs_info->unused_bgs)) { + u64 start, end; + int trimming; + + block_group = list_first_entry(&fs_info->unused_bgs, + struct btrfs_block_group_cache, + bg_list); + list_del_init(&block_group->bg_list); + + space_info = block_group->space_info; + + if (ret || btrfs_mixed_space_info(space_info)) { + btrfs_put_block_group(block_group); + continue; + } + spin_unlock(&fs_info->unused_bgs_lock); + + mutex_lock(&fs_info->delete_unused_bgs_mutex); + + /* Don't want to race with allocators so take the groups_sem */ + down_write(&space_info->groups_sem); + spin_lock(&block_group->lock); + if (block_group->reserved || block_group->pinned || + btrfs_block_group_used(&block_group->item) || + block_group->ro || + list_is_singular(&block_group->list)) { + /* + * We want to bail if we made new allocations or have + * outstanding allocations in this block group. We do + * the ro check in case balance is currently acting on + * this block group. + */ + trace_btrfs_skip_unused_block_group(block_group); + spin_unlock(&block_group->lock); + up_write(&space_info->groups_sem); + goto next; + } + spin_unlock(&block_group->lock); + + /* We don't want to force the issue, only flip if it's ok. */ + ret = __btrfs_inc_block_group_ro(block_group, 0); + up_write(&space_info->groups_sem); + if (ret < 0) { + ret = 0; + goto next; + } + + /* + * Want to do this before we do anything else so we can recover + * properly if we fail to join the transaction. + */ + trans = btrfs_start_trans_remove_block_group(fs_info, + block_group->key.objectid); + if (IS_ERR(trans)) { + btrfs_dec_block_group_ro(block_group); + ret = PTR_ERR(trans); + goto next; + } + + /* + * We could have pending pinned extents for this block group, + * just delete them, we don't care about them anymore. + */ + start = block_group->key.objectid; + end = start + block_group->key.offset - 1; + /* + * Hold the unused_bg_unpin_mutex lock to avoid racing with + * btrfs_finish_extent_commit(). If we are at transaction N, + * another task might be running finish_extent_commit() for the + * previous transaction N - 1, and have seen a range belonging + * to the block group in freed_extents[] before we were able to + * clear the whole block group range from freed_extents[]. This + * means that task can lookup for the block group after we + * unpinned it from freed_extents[] and removed it, leading to + * a BUG_ON() at btrfs_unpin_extent_range(). + */ + mutex_lock(&fs_info->unused_bg_unpin_mutex); + ret = clear_extent_bits(&fs_info->freed_extents[0], start, end, + EXTENT_DIRTY); + if (ret) { + mutex_unlock(&fs_info->unused_bg_unpin_mutex); + btrfs_dec_block_group_ro(block_group); + goto end_trans; + } + ret = clear_extent_bits(&fs_info->freed_extents[1], start, end, + EXTENT_DIRTY); + if (ret) { + mutex_unlock(&fs_info->unused_bg_unpin_mutex); + btrfs_dec_block_group_ro(block_group); + goto end_trans; + } + mutex_unlock(&fs_info->unused_bg_unpin_mutex); + + /* Reset pinned so btrfs_put_block_group doesn't complain */ + spin_lock(&space_info->lock); + spin_lock(&block_group->lock); + + btrfs_space_info_update_bytes_pinned(fs_info, space_info, + -block_group->pinned); + space_info->bytes_readonly += block_group->pinned; + percpu_counter_add_batch(&space_info->total_bytes_pinned, + -block_group->pinned, + BTRFS_TOTAL_BYTES_PINNED_BATCH); + block_group->pinned = 0; + + spin_unlock(&block_group->lock); + spin_unlock(&space_info->lock); + + /* DISCARD can flip during remount */ + trimming = btrfs_test_opt(fs_info, DISCARD); + + /* Implicit trim during transaction commit. */ + if (trimming) + btrfs_get_block_group_trimming(block_group); + + /* + * Btrfs_remove_chunk will abort the transaction if things go + * horribly wrong. + */ + ret = btrfs_remove_chunk(trans, block_group->key.objectid); + + if (ret) { + if (trimming) + btrfs_put_block_group_trimming(block_group); + goto end_trans; + } + + /* + * If we're not mounted with -odiscard, we can just forget + * about this block group. Otherwise we'll need to wait + * until transaction commit to do the actual discard. + */ + if (trimming) { + spin_lock(&fs_info->unused_bgs_lock); + /* + * A concurrent scrub might have added us to the list + * fs_info->unused_bgs, so use a list_move operation + * to add the block group to the deleted_bgs list. + */ + list_move(&block_group->bg_list, + &trans->transaction->deleted_bgs); + spin_unlock(&fs_info->unused_bgs_lock); + btrfs_get_block_group(block_group); + } +end_trans: + btrfs_end_transaction(trans); +next: + mutex_unlock(&fs_info->delete_unused_bgs_mutex); + btrfs_put_block_group(block_group); + spin_lock(&fs_info->unused_bgs_lock); + } + spin_unlock(&fs_info->unused_bgs_lock); +} + +void btrfs_mark_bg_unused(struct btrfs_block_group_cache *bg) +{ + struct btrfs_fs_info *fs_info = bg->fs_info; + + spin_lock(&fs_info->unused_bgs_lock); + if (list_empty(&bg->bg_list)) { + btrfs_get_block_group(bg); + trace_btrfs_add_unused_block_group(bg); + list_add_tail(&bg->bg_list, &fs_info->unused_bgs); + } + spin_unlock(&fs_info->unused_bgs_lock); +} diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h index 143baaa54684..f1fe14ba2702 100644 --- a/fs/btrfs/block-group.h +++ b/fs/btrfs/block-group.h @@ -176,6 +176,13 @@ struct btrfs_caching_control *btrfs_get_caching_control( struct btrfs_block_group_cache *cache); u64 add_new_free_space(struct btrfs_block_group_cache *block_group, u64 start, u64 end); +struct btrfs_trans_handle *btrfs_start_trans_remove_block_group( + struct btrfs_fs_info *fs_info, + const u64 chunk_offset); +int btrfs_remove_block_group(struct btrfs_trans_handle *trans, + u64 group_start, struct extent_map *em); +void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info); +void btrfs_mark_bg_unused(struct btrfs_block_group_cache *bg); static inline int btrfs_block_group_cache_done( struct btrfs_block_group_cache *cache) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 17eb4c91f0e1..aedee3f66764 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2532,12 +2532,6 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info); int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used, u64 type, u64 chunk_offset, u64 size); -struct btrfs_trans_handle *btrfs_start_trans_remove_block_group( - struct btrfs_fs_info *fs_info, - const u64 chunk_offset); -int btrfs_remove_block_group(struct btrfs_trans_handle *trans, - u64 group_start, struct extent_map *em); -void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info); void btrfs_get_block_group_trimming(struct btrfs_block_group_cache *cache); void btrfs_put_block_group_trimming(struct btrfs_block_group_cache *cache); void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans); @@ -2618,7 +2612,6 @@ int btrfs_start_write_no_snapshotting(struct btrfs_root *root); void btrfs_end_write_no_snapshotting(struct btrfs_root *root); void btrfs_wait_for_snapshot_creation(struct btrfs_root *root); void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type); -void btrfs_mark_bg_unused(struct btrfs_block_group_cache *bg); /* ctree.c */ int btrfs_bin_search(struct extent_buffer *eb, const struct btrfs_key *key, diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 08bd67169590..775d78a101b0 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7501,530 +7501,6 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used, return 0; } -static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) -{ - u64 extra_flags = chunk_to_extended(flags) & - BTRFS_EXTENDED_PROFILE_MASK; - - write_seqlock(&fs_info->profiles_lock); - if (flags & BTRFS_BLOCK_GROUP_DATA) - fs_info->avail_data_alloc_bits &= ~extra_flags; - if (flags & BTRFS_BLOCK_GROUP_METADATA) - fs_info->avail_metadata_alloc_bits &= ~extra_flags; - if (flags & BTRFS_BLOCK_GROUP_SYSTEM) - fs_info->avail_system_alloc_bits &= ~extra_flags; - write_sequnlock(&fs_info->profiles_lock); -} - -/* - * Clear incompat bits for the following feature(s): - * - * - RAID56 - in case there's neither RAID5 nor RAID6 profile block group - * in the whole filesystem - */ -static void clear_incompat_bg_bits(struct btrfs_fs_info *fs_info, u64 flags) -{ - if (flags & BTRFS_BLOCK_GROUP_RAID56_MASK) { - struct list_head *head = &fs_info->space_info; - struct btrfs_space_info *sinfo; - - list_for_each_entry_rcu(sinfo, head, list) { - bool found = false; - - down_read(&sinfo->groups_sem); - if (!list_empty(&sinfo->block_groups[BTRFS_RAID_RAID5])) - found = true; - if (!list_empty(&sinfo->block_groups[BTRFS_RAID_RAID6])) - found = true; - up_read(&sinfo->groups_sem); - - if (found) - return; - } - btrfs_clear_fs_incompat(fs_info, RAID56); - } -} - -int btrfs_remove_block_group(struct btrfs_trans_handle *trans, - u64 group_start, struct extent_map *em) -{ - struct btrfs_fs_info *fs_info = trans->fs_info; - struct btrfs_root *root = fs_info->extent_root; - struct btrfs_path *path; - struct btrfs_block_group_cache *block_group; - struct btrfs_free_cluster *cluster; - struct btrfs_root *tree_root = fs_info->tree_root; - struct btrfs_key key; - struct inode *inode; - struct kobject *kobj = NULL; - int ret; - int index; - int factor; - struct btrfs_caching_control *caching_ctl = NULL; - bool remove_em; - bool remove_rsv = false; - - block_group = btrfs_lookup_block_group(fs_info, group_start); - BUG_ON(!block_group); - BUG_ON(!block_group->ro); - - trace_btrfs_remove_block_group(block_group); - /* - * Free the reserved super bytes from this block group before - * remove it. - */ - btrfs_free_excluded_extents(block_group); - btrfs_free_ref_tree_range(fs_info, block_group->key.objectid, - block_group->key.offset); - - memcpy(&key, &block_group->key, sizeof(key)); - index = btrfs_bg_flags_to_raid_index(block_group->flags); - factor = btrfs_bg_type_to_factor(block_group->flags); - - /* make sure this block group isn't part of an allocation cluster */ - cluster = &fs_info->data_alloc_cluster; - spin_lock(&cluster->refill_lock); - btrfs_return_cluster_to_free_space(block_group, cluster); - spin_unlock(&cluster->refill_lock); - - /* - * make sure this block group isn't part of a metadata - * allocation cluster - */ - cluster = &fs_info->meta_alloc_cluster; - spin_lock(&cluster->refill_lock); - btrfs_return_cluster_to_free_space(block_group, cluster); - spin_unlock(&cluster->refill_lock); - - path = btrfs_alloc_path(); - if (!path) { - ret = -ENOMEM; - goto out; - } - - /* - * get the inode first so any iput calls done for the io_list - * aren't the final iput (no unlinks allowed now) - */ - inode = lookup_free_space_inode(block_group, path); - - mutex_lock(&trans->transaction->cache_write_mutex); - /* - * Make sure our free space cache IO is done before removing the - * free space inode - */ - spin_lock(&trans->transaction->dirty_bgs_lock); - if (!list_empty(&block_group->io_list)) { - list_del_init(&block_group->io_list); - - WARN_ON(!IS_ERR(inode) && inode != block_group->io_ctl.inode); - - spin_unlock(&trans->transaction->dirty_bgs_lock); - btrfs_wait_cache_io(trans, block_group, path); - btrfs_put_block_group(block_group); - spin_lock(&trans->transaction->dirty_bgs_lock); - } - - if (!list_empty(&block_group->dirty_list)) { - list_del_init(&block_group->dirty_list); - remove_rsv = true; - btrfs_put_block_group(block_group); - } - spin_unlock(&trans->transaction->dirty_bgs_lock); - mutex_unlock(&trans->transaction->cache_write_mutex); - - if (!IS_ERR(inode)) { - ret = btrfs_orphan_add(trans, BTRFS_I(inode)); - if (ret) { - btrfs_add_delayed_iput(inode); - goto out; - } - clear_nlink(inode); - /* One for the block groups ref */ - spin_lock(&block_group->lock); - if (block_group->iref) { - block_group->iref = 0; - block_group->inode = NULL; - spin_unlock(&block_group->lock); - iput(inode); - } else { - spin_unlock(&block_group->lock); - } - /* One for our lookup ref */ - btrfs_add_delayed_iput(inode); - } - - key.objectid = BTRFS_FREE_SPACE_OBJECTID; - key.offset = block_group->key.objectid; - key.type = 0; - - ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1); - if (ret < 0) - goto out; - if (ret > 0) - btrfs_release_path(path); - if (ret == 0) { - ret = btrfs_del_item(trans, tree_root, path); - if (ret) - goto out; - btrfs_release_path(path); - } - - spin_lock(&fs_info->block_group_cache_lock); - rb_erase(&block_group->cache_node, - &fs_info->block_group_cache_tree); - RB_CLEAR_NODE(&block_group->cache_node); - - if (fs_info->first_logical_byte == block_group->key.objectid) - fs_info->first_logical_byte = (u64)-1; - spin_unlock(&fs_info->block_group_cache_lock); - - down_write(&block_group->space_info->groups_sem); - /* - * we must use list_del_init so people can check to see if they - * are still on the list after taking the semaphore - */ - list_del_init(&block_group->list); - if (list_empty(&block_group->space_info->block_groups[index])) { - kobj = block_group->space_info->block_group_kobjs[index]; - block_group->space_info->block_group_kobjs[index] = NULL; - clear_avail_alloc_bits(fs_info, block_group->flags); - } - up_write(&block_group->space_info->groups_sem); - clear_incompat_bg_bits(fs_info, block_group->flags); - if (kobj) { - kobject_del(kobj); - kobject_put(kobj); - } - - if (block_group->has_caching_ctl) - caching_ctl = btrfs_get_caching_control(block_group); - if (block_group->cached == BTRFS_CACHE_STARTED) - btrfs_wait_block_group_cache_done(block_group); - if (block_group->has_caching_ctl) { - down_write(&fs_info->commit_root_sem); - if (!caching_ctl) { - struct btrfs_caching_control *ctl; - - list_for_each_entry(ctl, - &fs_info->caching_block_groups, list) - if (ctl->block_group == block_group) { - caching_ctl = ctl; - refcount_inc(&caching_ctl->count); - break; - } - } - if (caching_ctl) - list_del_init(&caching_ctl->list); - up_write(&fs_info->commit_root_sem); - if (caching_ctl) { - /* Once for the caching bgs list and once for us. */ - btrfs_put_caching_control(caching_ctl); - btrfs_put_caching_control(caching_ctl); - } - } - - spin_lock(&trans->transaction->dirty_bgs_lock); - WARN_ON(!list_empty(&block_group->dirty_list)); - WARN_ON(!list_empty(&block_group->io_list)); - spin_unlock(&trans->transaction->dirty_bgs_lock); - - btrfs_remove_free_space_cache(block_group); - - spin_lock(&block_group->space_info->lock); - list_del_init(&block_group->ro_list); - - if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) { - WARN_ON(block_group->space_info->total_bytes - < block_group->key.offset); - WARN_ON(block_group->space_info->bytes_readonly - < block_group->key.offset); - WARN_ON(block_group->space_info->disk_total - < block_group->key.offset * factor); - } - block_group->space_info->total_bytes -= block_group->key.offset; - block_group->space_info->bytes_readonly -= block_group->key.offset; - block_group->space_info->disk_total -= block_group->key.offset * factor; - - spin_unlock(&block_group->space_info->lock); - - memcpy(&key, &block_group->key, sizeof(key)); - - mutex_lock(&fs_info->chunk_mutex); - spin_lock(&block_group->lock); - block_group->removed = 1; - /* - * At this point trimming can't start on this block group, because we - * removed the block group from the tree fs_info->block_group_cache_tree - * so no one can't find it anymore and even if someone already got this - * block group before we removed it from the rbtree, they have already - * incremented block_group->trimming - if they didn't, they won't find - * any free space entries because we already removed them all when we - * called btrfs_remove_free_space_cache(). - * - * And we must not remove the extent map from the fs_info->mapping_tree - * to prevent the same logical address range and physical device space - * ranges from being reused for a new block group. This is because our - * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is - * completely transactionless, so while it is trimming a range the - * currently running transaction might finish and a new one start, - * allowing for new block groups to be created that can reuse the same - * physical device locations unless we take this special care. - * - * There may also be an implicit trim operation if the file system - * is mounted with -odiscard. The same protections must remain - * in place until the extents have been discarded completely when - * the transaction commit has completed. - */ - remove_em = (atomic_read(&block_group->trimming) == 0); - spin_unlock(&block_group->lock); - - mutex_unlock(&fs_info->chunk_mutex); - - ret = remove_block_group_free_space(trans, block_group); - if (ret) - goto out; - - btrfs_put_block_group(block_group); - btrfs_put_block_group(block_group); - - ret = btrfs_search_slot(trans, root, &key, path, -1, 1); - if (ret > 0) - ret = -EIO; - if (ret < 0) - goto out; - - ret = btrfs_del_item(trans, root, path); - if (ret) - goto out; - - if (remove_em) { - struct extent_map_tree *em_tree; - - em_tree = &fs_info->mapping_tree; - write_lock(&em_tree->lock); - remove_extent_mapping(em_tree, em); - write_unlock(&em_tree->lock); - /* once for the tree */ - free_extent_map(em); - } -out: - if (remove_rsv) - btrfs_delayed_refs_rsv_release(fs_info, 1); - btrfs_free_path(path); - return ret; -} - -struct btrfs_trans_handle * -btrfs_start_trans_remove_block_group(struct btrfs_fs_info *fs_info, - const u64 chunk_offset) -{ - struct extent_map_tree *em_tree = &fs_info->mapping_tree; - struct extent_map *em; - struct map_lookup *map; - unsigned int num_items; - - read_lock(&em_tree->lock); - em = lookup_extent_mapping(em_tree, chunk_offset, 1); - read_unlock(&em_tree->lock); - ASSERT(em && em->start == chunk_offset); - - /* - * We need to reserve 3 + N units from the metadata space info in order - * to remove a block group (done at btrfs_remove_chunk() and at - * btrfs_remove_block_group()), which are used for: - * - * 1 unit for adding the free space inode's orphan (located in the tree - * of tree roots). - * 1 unit for deleting the block group item (located in the extent - * tree). - * 1 unit for deleting the free space item (located in tree of tree - * roots). - * N units for deleting N device extent items corresponding to each - * stripe (located in the device tree). - * - * In order to remove a block group we also need to reserve units in the - * system space info in order to update the chunk tree (update one or - * more device items and remove one chunk item), but this is done at - * btrfs_remove_chunk() through a call to check_system_chunk(). - */ - map = em->map_lookup; - num_items = 3 + map->num_stripes; - free_extent_map(em); - - return btrfs_start_transaction_fallback_global_rsv(fs_info->extent_root, - num_items, 1); -} - -/* - * Process the unused_bgs list and remove any that don't have any allocated - * space inside of them. - */ -void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) -{ - struct btrfs_block_group_cache *block_group; - struct btrfs_space_info *space_info; - struct btrfs_trans_handle *trans; - int ret = 0; - - if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags)) - return; - - spin_lock(&fs_info->unused_bgs_lock); - while (!list_empty(&fs_info->unused_bgs)) { - u64 start, end; - int trimming; - - block_group = list_first_entry(&fs_info->unused_bgs, - struct btrfs_block_group_cache, - bg_list); - list_del_init(&block_group->bg_list); - - space_info = block_group->space_info; - - if (ret || btrfs_mixed_space_info(space_info)) { - btrfs_put_block_group(block_group); - continue; - } - spin_unlock(&fs_info->unused_bgs_lock); - - mutex_lock(&fs_info->delete_unused_bgs_mutex); - - /* Don't want to race with allocators so take the groups_sem */ - down_write(&space_info->groups_sem); - spin_lock(&block_group->lock); - if (block_group->reserved || block_group->pinned || - btrfs_block_group_used(&block_group->item) || - block_group->ro || - list_is_singular(&block_group->list)) { - /* - * We want to bail if we made new allocations or have - * outstanding allocations in this block group. We do - * the ro check in case balance is currently acting on - * this block group. - */ - trace_btrfs_skip_unused_block_group(block_group); - spin_unlock(&block_group->lock); - up_write(&space_info->groups_sem); - goto next; - } - spin_unlock(&block_group->lock); - - /* We don't want to force the issue, only flip if it's ok. */ - ret = __btrfs_inc_block_group_ro(block_group, 0); - up_write(&space_info->groups_sem); - if (ret < 0) { - ret = 0; - goto next; - } - - /* - * Want to do this before we do anything else so we can recover - * properly if we fail to join the transaction. - */ - trans = btrfs_start_trans_remove_block_group(fs_info, - block_group->key.objectid); - if (IS_ERR(trans)) { - btrfs_dec_block_group_ro(block_group); - ret = PTR_ERR(trans); - goto next; - } - - /* - * We could have pending pinned extents for this block group, - * just delete them, we don't care about them anymore. - */ - start = block_group->key.objectid; - end = start + block_group->key.offset - 1; - /* - * Hold the unused_bg_unpin_mutex lock to avoid racing with - * btrfs_finish_extent_commit(). If we are at transaction N, - * another task might be running finish_extent_commit() for the - * previous transaction N - 1, and have seen a range belonging - * to the block group in freed_extents[] before we were able to - * clear the whole block group range from freed_extents[]. This - * means that task can lookup for the block group after we - * unpinned it from freed_extents[] and removed it, leading to - * a BUG_ON() at btrfs_unpin_extent_range(). - */ - mutex_lock(&fs_info->unused_bg_unpin_mutex); - ret = clear_extent_bits(&fs_info->freed_extents[0], start, end, - EXTENT_DIRTY); - if (ret) { - mutex_unlock(&fs_info->unused_bg_unpin_mutex); - btrfs_dec_block_group_ro(block_group); - goto end_trans; - } - ret = clear_extent_bits(&fs_info->freed_extents[1], start, end, - EXTENT_DIRTY); - if (ret) { - mutex_unlock(&fs_info->unused_bg_unpin_mutex); - btrfs_dec_block_group_ro(block_group); - goto end_trans; - } - mutex_unlock(&fs_info->unused_bg_unpin_mutex); - - /* Reset pinned so btrfs_put_block_group doesn't complain */ - spin_lock(&space_info->lock); - spin_lock(&block_group->lock); - - btrfs_space_info_update_bytes_pinned(fs_info, space_info, - -block_group->pinned); - space_info->bytes_readonly += block_group->pinned; - percpu_counter_add_batch(&space_info->total_bytes_pinned, - -block_group->pinned, - BTRFS_TOTAL_BYTES_PINNED_BATCH); - block_group->pinned = 0; - - spin_unlock(&block_group->lock); - spin_unlock(&space_info->lock); - - /* DISCARD can flip during remount */ - trimming = btrfs_test_opt(fs_info, DISCARD); - - /* Implicit trim during transaction commit. */ - if (trimming) - btrfs_get_block_group_trimming(block_group); - - /* - * Btrfs_remove_chunk will abort the transaction if things go - * horribly wrong. - */ - ret = btrfs_remove_chunk(trans, block_group->key.objectid); - - if (ret) { - if (trimming) - btrfs_put_block_group_trimming(block_group); - goto end_trans; - } - - /* - * If we're not mounted with -odiscard, we can just forget - * about this block group. Otherwise we'll need to wait - * until transaction commit to do the actual discard. - */ - if (trimming) { - spin_lock(&fs_info->unused_bgs_lock); - /* - * A concurrent scrub might have added us to the list - * fs_info->unused_bgs, so use a list_move operation - * to add the block group to the deleted_bgs list. - */ - list_move(&block_group->bg_list, - &trans->transaction->deleted_bgs); - spin_unlock(&fs_info->unused_bgs_lock); - btrfs_get_block_group(block_group); - } -end_trans: - btrfs_end_transaction(trans); -next: - mutex_unlock(&fs_info->delete_unused_bgs_mutex); - btrfs_put_block_group(block_group); - spin_lock(&fs_info->unused_bgs_lock); - } - spin_unlock(&fs_info->unused_bgs_lock); -} - int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info, u64 start, u64 end) { @@ -8272,16 +7748,3 @@ void btrfs_wait_for_snapshot_creation(struct btrfs_root *root) !atomic_read(&root->will_be_snapshotted)); } } - -void btrfs_mark_bg_unused(struct btrfs_block_group_cache *bg) -{ - struct btrfs_fs_info *fs_info = bg->fs_info; - - spin_lock(&fs_info->unused_bgs_lock); - if (list_empty(&bg->bg_list)) { - btrfs_get_block_group(bg); - trace_btrfs_add_unused_block_group(bg); - list_add_tail(&bg->bg_list, &fs_info->unused_bgs); - } - spin_unlock(&fs_info->unused_bgs_lock); -} -- GitLab