| // SPDX-License-Identifier: GPL-2.0 |
| |
| #include "misc.h" |
| #include "ctree.h" |
| #include "space-info.h" |
| #include "sysfs.h" |
| #include "volumes.h" |
| #include "free-space-cache.h" |
| #include "ordered-data.h" |
| #include "transaction.h" |
| #include "block-group.h" |
| |
| u64 btrfs_space_info_used(struct btrfs_space_info *s_info, |
| bool may_use_included) |
| { |
| ASSERT(s_info); |
| return s_info->bytes_used + s_info->bytes_reserved + |
| s_info->bytes_pinned + s_info->bytes_readonly + |
| (may_use_included ? s_info->bytes_may_use : 0); |
| } |
| |
| /* |
| * after adding space to the filesystem, we need to clear the full flags |
| * on all the space infos. |
| */ |
| void btrfs_clear_space_info_full(struct btrfs_fs_info *info) |
| { |
| struct list_head *head = &info->space_info; |
| struct btrfs_space_info *found; |
| |
| rcu_read_lock(); |
| list_for_each_entry_rcu(found, head, list) |
| found->full = 0; |
| rcu_read_unlock(); |
| } |
| |
| static int create_space_info(struct btrfs_fs_info *info, u64 flags) |
| { |
| |
| struct btrfs_space_info *space_info; |
| int i; |
| int ret; |
| |
| space_info = kzalloc(sizeof(*space_info), GFP_NOFS); |
| if (!space_info) |
| return -ENOMEM; |
| |
| ret = percpu_counter_init(&space_info->total_bytes_pinned, 0, |
| GFP_KERNEL); |
| if (ret) { |
| kfree(space_info); |
| return ret; |
| } |
| |
| for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) |
| INIT_LIST_HEAD(&space_info->block_groups[i]); |
| init_rwsem(&space_info->groups_sem); |
| spin_lock_init(&space_info->lock); |
| space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK; |
| space_info->force_alloc = CHUNK_ALLOC_NO_FORCE; |
| init_waitqueue_head(&space_info->wait); |
| INIT_LIST_HEAD(&space_info->ro_bgs); |
| INIT_LIST_HEAD(&space_info->tickets); |
| INIT_LIST_HEAD(&space_info->priority_tickets); |
| |
| ret = btrfs_sysfs_add_space_info_type(info, space_info); |
| if (ret) |
| return ret; |
| |
| list_add_rcu(&space_info->list, &info->space_info); |
| if (flags & BTRFS_BLOCK_GROUP_DATA) |
| info->data_sinfo = space_info; |
| |
| return ret; |
| } |
| |
| int btrfs_init_space_info(struct btrfs_fs_info *fs_info) |
| { |
| struct btrfs_super_block *disk_super; |
| u64 features; |
| u64 flags; |
| int mixed = 0; |
| int ret; |
| |
| disk_super = fs_info->super_copy; |
| if (!btrfs_super_root(disk_super)) |
| return -EINVAL; |
| |
| features = btrfs_super_incompat_flags(disk_super); |
| if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) |
| mixed = 1; |
| |
| flags = BTRFS_BLOCK_GROUP_SYSTEM; |
| ret = create_space_info(fs_info, flags); |
| if (ret) |
| goto out; |
| |
| if (mixed) { |
| flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA; |
| ret = create_space_info(fs_info, flags); |
| } else { |
| flags = BTRFS_BLOCK_GROUP_METADATA; |
| ret = create_space_info(fs_info, flags); |
| if (ret) |
| goto out; |
| |
| flags = BTRFS_BLOCK_GROUP_DATA; |
| ret = create_space_info(fs_info, flags); |
| } |
| out: |
| return ret; |
| } |
| |
| void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags, |
| u64 total_bytes, u64 bytes_used, |
| u64 bytes_readonly, |
| struct btrfs_space_info **space_info) |
| { |
| struct btrfs_space_info *found; |
| int factor; |
| |
| factor = btrfs_bg_type_to_factor(flags); |
| |
| found = btrfs_find_space_info(info, flags); |
| ASSERT(found); |
| spin_lock(&found->lock); |
| found->total_bytes += total_bytes; |
| found->disk_total += total_bytes * factor; |
| found->bytes_used += bytes_used; |
| found->disk_used += bytes_used * factor; |
| found->bytes_readonly += bytes_readonly; |
| if (total_bytes > 0) |
| found->full = 0; |
| btrfs_space_info_add_new_bytes(info, found, |
| total_bytes - bytes_used - |
| bytes_readonly); |
| spin_unlock(&found->lock); |
| *space_info = found; |
| } |
| |
| struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info, |
| u64 flags) |
| { |
| struct list_head *head = &info->space_info; |
| struct btrfs_space_info *found; |
| |
| flags &= BTRFS_BLOCK_GROUP_TYPE_MASK; |
| |
| rcu_read_lock(); |
| list_for_each_entry_rcu(found, head, list) { |
| if (found->flags & flags) { |
| rcu_read_unlock(); |
| return found; |
| } |
| } |
| rcu_read_unlock(); |
| return NULL; |
| } |
| |
| static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global) |
| { |
| return (global->size << 1); |
| } |
| |
| static int can_overcommit(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, u64 bytes, |
| enum btrfs_reserve_flush_enum flush, |
| bool system_chunk) |
| { |
| struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; |
| u64 profile; |
| u64 space_size; |
| u64 avail; |
| u64 used; |
| int factor; |
| |
| /* Don't overcommit when in mixed mode. */ |
| if (space_info->flags & BTRFS_BLOCK_GROUP_DATA) |
| return 0; |
| |
| if (system_chunk) |
| profile = btrfs_system_alloc_profile(fs_info); |
| else |
| profile = btrfs_metadata_alloc_profile(fs_info); |
| |
| used = btrfs_space_info_used(space_info, false); |
| |
| /* |
| * We only want to allow over committing if we have lots of actual space |
| * free, but if we don't have enough space to handle the global reserve |
| * space then we could end up having a real enospc problem when trying |
| * to allocate a chunk or some other such important allocation. |
| */ |
| spin_lock(&global_rsv->lock); |
| space_size = calc_global_rsv_need_space(global_rsv); |
| spin_unlock(&global_rsv->lock); |
| if (used + space_size >= space_info->total_bytes) |
| return 0; |
| |
| used += space_info->bytes_may_use; |
| |
| avail = atomic64_read(&fs_info->free_chunk_space); |
| |
| /* |
| * If we have dup, raid1 or raid10 then only half of the free |
| * space is actually usable. For raid56, the space info used |
| * doesn't include the parity drive, so we don't have to |
| * change the math |
| */ |
| factor = btrfs_bg_type_to_factor(profile); |
| avail = div_u64(avail, factor); |
| |
| /* |
| * If we aren't flushing all things, let us overcommit up to |
| * 1/2th of the space. If we can flush, don't let us overcommit |
| * too much, let it overcommit up to 1/8 of the space. |
| */ |
| if (flush == BTRFS_RESERVE_FLUSH_ALL) |
| avail >>= 3; |
| else |
| avail >>= 1; |
| |
| if (used + bytes < space_info->total_bytes + avail) |
| return 1; |
| return 0; |
| } |
| |
| /* |
| * This is for space we already have accounted in space_info->bytes_may_use, so |
| * basically when we're returning space from block_rsv's. |
| */ |
| void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, |
| u64 num_bytes) |
| { |
| struct reserve_ticket *ticket; |
| struct list_head *head; |
| u64 used; |
| enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH; |
| bool check_overcommit = false; |
| |
| spin_lock(&space_info->lock); |
| head = &space_info->priority_tickets; |
| |
| /* |
| * If we are over our limit then we need to check and see if we can |
| * overcommit, and if we can't then we just need to free up our space |
| * and not satisfy any requests. |
| */ |
| used = btrfs_space_info_used(space_info, true); |
| if (used - num_bytes >= space_info->total_bytes) |
| check_overcommit = true; |
| again: |
| while (!list_empty(head) && num_bytes) { |
| ticket = list_first_entry(head, struct reserve_ticket, |
| list); |
| /* |
| * We use 0 bytes because this space is already reserved, so |
| * adding the ticket space would be a double count. |
| */ |
| if (check_overcommit && |
| !can_overcommit(fs_info, space_info, 0, flush, false)) |
| break; |
| if (num_bytes >= ticket->bytes) { |
| list_del_init(&ticket->list); |
| num_bytes -= ticket->bytes; |
| ticket->bytes = 0; |
| space_info->tickets_id++; |
| wake_up(&ticket->wait); |
| } else { |
| ticket->bytes -= num_bytes; |
| num_bytes = 0; |
| } |
| } |
| |
| if (num_bytes && head == &space_info->priority_tickets) { |
| head = &space_info->tickets; |
| flush = BTRFS_RESERVE_FLUSH_ALL; |
| goto again; |
| } |
| btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes); |
| trace_btrfs_space_reservation(fs_info, "space_info", |
| space_info->flags, num_bytes, 0); |
| spin_unlock(&space_info->lock); |
| } |
| |
| /* |
| * This is for newly allocated space that isn't accounted in |
| * space_info->bytes_may_use yet. So if we allocate a chunk or unpin an extent |
| * we use this helper. |
| */ |
| void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, |
| u64 num_bytes) |
| { |
| struct reserve_ticket *ticket; |
| struct list_head *head = &space_info->priority_tickets; |
| |
| again: |
| while (!list_empty(head) && num_bytes) { |
| ticket = list_first_entry(head, struct reserve_ticket, |
| list); |
| if (num_bytes >= ticket->bytes) { |
| trace_btrfs_space_reservation(fs_info, "space_info", |
| space_info->flags, |
| ticket->bytes, 1); |
| list_del_init(&ticket->list); |
| num_bytes -= ticket->bytes; |
| btrfs_space_info_update_bytes_may_use(fs_info, |
| space_info, |
| ticket->bytes); |
| ticket->bytes = 0; |
| space_info->tickets_id++; |
| wake_up(&ticket->wait); |
| } else { |
| trace_btrfs_space_reservation(fs_info, "space_info", |
| space_info->flags, |
| num_bytes, 1); |
| btrfs_space_info_update_bytes_may_use(fs_info, |
| space_info, |
| num_bytes); |
| ticket->bytes -= num_bytes; |
| num_bytes = 0; |
| } |
| } |
| |
| if (num_bytes && head == &space_info->priority_tickets) { |
| head = &space_info->tickets; |
| goto again; |
| } |
| } |
| |
| #define DUMP_BLOCK_RSV(fs_info, rsv_name) \ |
| do { \ |
| struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name; \ |
| spin_lock(&__rsv->lock); \ |
| btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu", \ |
| __rsv->size, __rsv->reserved); \ |
| spin_unlock(&__rsv->lock); \ |
| } while (0) |
| |
| void btrfs_dump_space_info(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *info, u64 bytes, |
| int dump_block_groups) |
| { |
| struct btrfs_block_group_cache *cache; |
| int index = 0; |
| |
| spin_lock(&info->lock); |
| btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull", |
| info->flags, |
| info->total_bytes - btrfs_space_info_used(info, true), |
| info->full ? "" : "not "); |
| btrfs_info(fs_info, |
| "space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu", |
| info->total_bytes, info->bytes_used, info->bytes_pinned, |
| info->bytes_reserved, info->bytes_may_use, |
| info->bytes_readonly); |
| spin_unlock(&info->lock); |
| |
| DUMP_BLOCK_RSV(fs_info, global_block_rsv); |
| DUMP_BLOCK_RSV(fs_info, trans_block_rsv); |
| DUMP_BLOCK_RSV(fs_info, chunk_block_rsv); |
| DUMP_BLOCK_RSV(fs_info, delayed_block_rsv); |
| DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv); |
| |
| if (!dump_block_groups) |
| return; |
| |
| down_read(&info->groups_sem); |
| again: |
| list_for_each_entry(cache, &info->block_groups[index], list) { |
| spin_lock(&cache->lock); |
| btrfs_info(fs_info, |
| "block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s", |
| cache->key.objectid, cache->key.offset, |
| btrfs_block_group_used(&cache->item), cache->pinned, |
| cache->reserved, cache->ro ? "[readonly]" : ""); |
| btrfs_dump_free_space(cache, bytes); |
| spin_unlock(&cache->lock); |
| } |
| if (++index < BTRFS_NR_RAID_TYPES) |
| goto again; |
| up_read(&info->groups_sem); |
| } |
| |
| static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info, |
| unsigned long nr_pages, int nr_items) |
| { |
| struct super_block *sb = fs_info->sb; |
| |
| if (down_read_trylock(&sb->s_umount)) { |
| writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE); |
| up_read(&sb->s_umount); |
| } else { |
| /* |
| * We needn't worry the filesystem going from r/w to r/o though |
| * we don't acquire ->s_umount mutex, because the filesystem |
| * should guarantee the delalloc inodes list be empty after |
| * the filesystem is readonly(all dirty pages are written to |
| * the disk). |
| */ |
| btrfs_start_delalloc_roots(fs_info, nr_items); |
| if (!current->journal_info) |
| btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1); |
| } |
| } |
| |
| static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info, |
| u64 to_reclaim) |
| { |
| u64 bytes; |
| u64 nr; |
| |
| bytes = btrfs_calc_insert_metadata_size(fs_info, 1); |
| nr = div64_u64(to_reclaim, bytes); |
| if (!nr) |
| nr = 1; |
| return nr; |
| } |
| |
| #define EXTENT_SIZE_PER_ITEM SZ_256K |
| |
| /* |
| * shrink metadata reservation for delalloc |
| */ |
| static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim, |
| u64 orig, bool wait_ordered) |
| { |
| struct btrfs_space_info *space_info; |
| struct btrfs_trans_handle *trans; |
| u64 delalloc_bytes; |
| u64 dio_bytes; |
| u64 async_pages; |
| u64 items; |
| long time_left; |
| unsigned long nr_pages; |
| int loops; |
| |
| /* Calc the number of the pages we need flush for space reservation */ |
| items = calc_reclaim_items_nr(fs_info, to_reclaim); |
| to_reclaim = items * EXTENT_SIZE_PER_ITEM; |
| |
| trans = (struct btrfs_trans_handle *)current->journal_info; |
| space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA); |
| |
| delalloc_bytes = percpu_counter_sum_positive( |
| &fs_info->delalloc_bytes); |
| dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes); |
| if (delalloc_bytes == 0 && dio_bytes == 0) { |
| if (trans) |
| return; |
| if (wait_ordered) |
| btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1); |
| return; |
| } |
| |
| /* |
| * If we are doing more ordered than delalloc we need to just wait on |
| * ordered extents, otherwise we'll waste time trying to flush delalloc |
| * that likely won't give us the space back we need. |
| */ |
| if (dio_bytes > delalloc_bytes) |
| wait_ordered = true; |
| |
| loops = 0; |
| while ((delalloc_bytes || dio_bytes) && loops < 3) { |
| nr_pages = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT; |
| |
| /* |
| * Triggers inode writeback for up to nr_pages. This will invoke |
| * ->writepages callback and trigger delalloc filling |
| * (btrfs_run_delalloc_range()). |
| */ |
| btrfs_writeback_inodes_sb_nr(fs_info, nr_pages, items); |
| |
| /* |
| * We need to wait for the compressed pages to start before |
| * we continue. |
| */ |
| async_pages = atomic_read(&fs_info->async_delalloc_pages); |
| if (!async_pages) |
| goto skip_async; |
| |
| /* |
| * Calculate how many compressed pages we want to be written |
| * before we continue. I.e if there are more async pages than we |
| * require wait_event will wait until nr_pages are written. |
| */ |
| if (async_pages <= nr_pages) |
| async_pages = 0; |
| else |
| async_pages -= nr_pages; |
| |
| wait_event(fs_info->async_submit_wait, |
| atomic_read(&fs_info->async_delalloc_pages) <= |
| (int)async_pages); |
| skip_async: |
| spin_lock(&space_info->lock); |
| if (list_empty(&space_info->tickets) && |
| list_empty(&space_info->priority_tickets)) { |
| spin_unlock(&space_info->lock); |
| break; |
| } |
| spin_unlock(&space_info->lock); |
| |
| loops++; |
| if (wait_ordered && !trans) { |
| btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1); |
| } else { |
| time_left = schedule_timeout_killable(1); |
| if (time_left) |
| break; |
| } |
| delalloc_bytes = percpu_counter_sum_positive( |
| &fs_info->delalloc_bytes); |
| dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes); |
| } |
| } |
| |
| /** |
| * maybe_commit_transaction - possibly commit the transaction if its ok to |
| * @root - the root we're allocating for |
| * @bytes - the number of bytes we want to reserve |
| * @force - force the commit |
| * |
| * This will check to make sure that committing the transaction will actually |
| * get us somewhere and then commit the transaction if it does. Otherwise it |
| * will return -ENOSPC. |
| */ |
| static int may_commit_transaction(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info) |
| { |
| struct reserve_ticket *ticket = NULL; |
| struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv; |
| struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv; |
| struct btrfs_trans_handle *trans; |
| u64 bytes_needed; |
| u64 reclaim_bytes = 0; |
| |
| trans = (struct btrfs_trans_handle *)current->journal_info; |
| if (trans) |
| return -EAGAIN; |
| |
| spin_lock(&space_info->lock); |
| if (!list_empty(&space_info->priority_tickets)) |
| ticket = list_first_entry(&space_info->priority_tickets, |
| struct reserve_ticket, list); |
| else if (!list_empty(&space_info->tickets)) |
| ticket = list_first_entry(&space_info->tickets, |
| struct reserve_ticket, list); |
| bytes_needed = (ticket) ? ticket->bytes : 0; |
| spin_unlock(&space_info->lock); |
| |
| if (!bytes_needed) |
| return 0; |
| |
| trans = btrfs_join_transaction(fs_info->extent_root); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| /* |
| * See if there is enough pinned space to make this reservation, or if |
| * we have block groups that are going to be freed, allowing us to |
| * possibly do a chunk allocation the next loop through. |
| */ |
| if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) || |
| __percpu_counter_compare(&space_info->total_bytes_pinned, |
| bytes_needed, |
| BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0) |
| goto commit; |
| |
| /* |
| * See if there is some space in the delayed insertion reservation for |
| * this reservation. |
| */ |
| if (space_info != delayed_rsv->space_info) |
| goto enospc; |
| |
| spin_lock(&delayed_rsv->lock); |
| reclaim_bytes += delayed_rsv->reserved; |
| spin_unlock(&delayed_rsv->lock); |
| |
| spin_lock(&delayed_refs_rsv->lock); |
| reclaim_bytes += delayed_refs_rsv->reserved; |
| spin_unlock(&delayed_refs_rsv->lock); |
| if (reclaim_bytes >= bytes_needed) |
| goto commit; |
| bytes_needed -= reclaim_bytes; |
| |
| if (__percpu_counter_compare(&space_info->total_bytes_pinned, |
| bytes_needed, |
| BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0) |
| goto enospc; |
| |
| commit: |
| return btrfs_commit_transaction(trans); |
| enospc: |
| btrfs_end_transaction(trans); |
| return -ENOSPC; |
| } |
| |
| /* |
| * Try to flush some data based on policy set by @state. This is only advisory |
| * and may fail for various reasons. The caller is supposed to examine the |
| * state of @space_info to detect the outcome. |
| */ |
| static void flush_space(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, u64 num_bytes, |
| int state) |
| { |
| struct btrfs_root *root = fs_info->extent_root; |
| struct btrfs_trans_handle *trans; |
| int nr; |
| int ret = 0; |
| |
| switch (state) { |
| case FLUSH_DELAYED_ITEMS_NR: |
| case FLUSH_DELAYED_ITEMS: |
| if (state == FLUSH_DELAYED_ITEMS_NR) |
| nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2; |
| else |
| nr = -1; |
| |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| break; |
| } |
| ret = btrfs_run_delayed_items_nr(trans, nr); |
| btrfs_end_transaction(trans); |
| break; |
| case FLUSH_DELALLOC: |
| case FLUSH_DELALLOC_WAIT: |
| shrink_delalloc(fs_info, num_bytes * 2, num_bytes, |
| state == FLUSH_DELALLOC_WAIT); |
| break; |
| case FLUSH_DELAYED_REFS_NR: |
| case FLUSH_DELAYED_REFS: |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| break; |
| } |
| if (state == FLUSH_DELAYED_REFS_NR) |
| nr = calc_reclaim_items_nr(fs_info, num_bytes); |
| else |
| nr = 0; |
| btrfs_run_delayed_refs(trans, nr); |
| btrfs_end_transaction(trans); |
| break; |
| case ALLOC_CHUNK: |
| case ALLOC_CHUNK_FORCE: |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| break; |
| } |
| ret = btrfs_chunk_alloc(trans, |
| btrfs_metadata_alloc_profile(fs_info), |
| (state == ALLOC_CHUNK) ? CHUNK_ALLOC_NO_FORCE : |
| CHUNK_ALLOC_FORCE); |
| btrfs_end_transaction(trans); |
| if (ret > 0 || ret == -ENOSPC) |
| ret = 0; |
| break; |
| case RUN_DELAYED_IPUTS: |
| /* |
| * If we have pending delayed iputs then we could free up a |
| * bunch of pinned space, so make sure we run the iputs before |
| * we do our pinned bytes check below. |
| */ |
| btrfs_run_delayed_iputs(fs_info); |
| btrfs_wait_on_delayed_iputs(fs_info); |
| break; |
| case COMMIT_TRANS: |
| ret = may_commit_transaction(fs_info, space_info); |
| break; |
| default: |
| ret = -ENOSPC; |
| break; |
| } |
| |
| trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state, |
| ret); |
| return; |
| } |
| |
| static inline u64 |
| btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, |
| bool system_chunk) |
| { |
| struct reserve_ticket *ticket; |
| u64 used; |
| u64 expected; |
| u64 to_reclaim = 0; |
| |
| list_for_each_entry(ticket, &space_info->tickets, list) |
| to_reclaim += ticket->bytes; |
| list_for_each_entry(ticket, &space_info->priority_tickets, list) |
| to_reclaim += ticket->bytes; |
| if (to_reclaim) |
| return to_reclaim; |
| |
| to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M); |
| if (can_overcommit(fs_info, space_info, to_reclaim, |
| BTRFS_RESERVE_FLUSH_ALL, system_chunk)) |
| return 0; |
| |
| used = btrfs_space_info_used(space_info, true); |
| |
| if (can_overcommit(fs_info, space_info, SZ_1M, |
| BTRFS_RESERVE_FLUSH_ALL, system_chunk)) |
| expected = div_factor_fine(space_info->total_bytes, 95); |
| else |
| expected = div_factor_fine(space_info->total_bytes, 90); |
| |
| if (used > expected) |
| to_reclaim = used - expected; |
| else |
| to_reclaim = 0; |
| to_reclaim = min(to_reclaim, space_info->bytes_may_use + |
| space_info->bytes_reserved); |
| return to_reclaim; |
| } |
| |
| static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, |
| u64 used, bool system_chunk) |
| { |
| u64 thresh = div_factor_fine(space_info->total_bytes, 98); |
| |
| /* If we're just plain full then async reclaim just slows us down. */ |
| if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh) |
| return 0; |
| |
| if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info, |
| system_chunk)) |
| return 0; |
| |
| return (used >= thresh && !btrfs_fs_closing(fs_info) && |
| !test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state)); |
| } |
| |
| static bool wake_all_tickets(struct list_head *head) |
| { |
| struct reserve_ticket *ticket; |
| |
| while (!list_empty(head)) { |
| ticket = list_first_entry(head, struct reserve_ticket, list); |
| list_del_init(&ticket->list); |
| ticket->error = -ENOSPC; |
| wake_up(&ticket->wait); |
| if (ticket->bytes != ticket->orig_bytes) |
| return true; |
| } |
| return false; |
| } |
| |
| /* |
| * This is for normal flushers, we can wait all goddamned day if we want to. We |
| * will loop and continuously try to flush as long as we are making progress. |
| * We count progress as clearing off tickets each time we have to loop. |
| */ |
| static void btrfs_async_reclaim_metadata_space(struct work_struct *work) |
| { |
| struct btrfs_fs_info *fs_info; |
| struct btrfs_space_info *space_info; |
| u64 to_reclaim; |
| int flush_state; |
| int commit_cycles = 0; |
| u64 last_tickets_id; |
| |
| fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work); |
| space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA); |
| |
| spin_lock(&space_info->lock); |
| to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info, |
| false); |
| if (!to_reclaim) { |
| space_info->flush = 0; |
| spin_unlock(&space_info->lock); |
| return; |
| } |
| last_tickets_id = space_info->tickets_id; |
| spin_unlock(&space_info->lock); |
| |
| flush_state = FLUSH_DELAYED_ITEMS_NR; |
| do { |
| flush_space(fs_info, space_info, to_reclaim, flush_state); |
| spin_lock(&space_info->lock); |
| if (list_empty(&space_info->tickets)) { |
| space_info->flush = 0; |
| spin_unlock(&space_info->lock); |
| return; |
| } |
| to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, |
| space_info, |
| false); |
| if (last_tickets_id == space_info->tickets_id) { |
| flush_state++; |
| } else { |
| last_tickets_id = space_info->tickets_id; |
| flush_state = FLUSH_DELAYED_ITEMS_NR; |
| if (commit_cycles) |
| commit_cycles--; |
| } |
| |
| /* |
| * We don't want to force a chunk allocation until we've tried |
| * pretty hard to reclaim space. Think of the case where we |
| * freed up a bunch of space and so have a lot of pinned space |
| * to reclaim. We would rather use that than possibly create a |
| * underutilized metadata chunk. So if this is our first run |
| * through the flushing state machine skip ALLOC_CHUNK_FORCE and |
| * commit the transaction. If nothing has changed the next go |
| * around then we can force a chunk allocation. |
| */ |
| if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles) |
| flush_state++; |
| |
| if (flush_state > COMMIT_TRANS) { |
| commit_cycles++; |
| if (commit_cycles > 2) { |
| if (wake_all_tickets(&space_info->tickets)) { |
| flush_state = FLUSH_DELAYED_ITEMS_NR; |
| commit_cycles--; |
| } else { |
| space_info->flush = 0; |
| } |
| } else { |
| flush_state = FLUSH_DELAYED_ITEMS_NR; |
| } |
| } |
| spin_unlock(&space_info->lock); |
| } while (flush_state <= COMMIT_TRANS); |
| } |
| |
| void btrfs_init_async_reclaim_work(struct work_struct *work) |
| { |
| INIT_WORK(work, btrfs_async_reclaim_metadata_space); |
| } |
| |
| static const enum btrfs_flush_state priority_flush_states[] = { |
| FLUSH_DELAYED_ITEMS_NR, |
| FLUSH_DELAYED_ITEMS, |
| ALLOC_CHUNK, |
| }; |
| |
| static const enum btrfs_flush_state evict_flush_states[] = { |
| FLUSH_DELAYED_ITEMS_NR, |
| FLUSH_DELAYED_ITEMS, |
| FLUSH_DELAYED_REFS_NR, |
| FLUSH_DELAYED_REFS, |
| FLUSH_DELALLOC, |
| FLUSH_DELALLOC_WAIT, |
| ALLOC_CHUNK, |
| COMMIT_TRANS, |
| }; |
| |
| static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, |
| struct reserve_ticket *ticket, |
| const enum btrfs_flush_state *states, |
| int states_nr) |
| { |
| u64 to_reclaim; |
| int flush_state; |
| |
| spin_lock(&space_info->lock); |
| to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info, |
| false); |
| if (!to_reclaim) { |
| spin_unlock(&space_info->lock); |
| return; |
| } |
| spin_unlock(&space_info->lock); |
| |
| flush_state = 0; |
| do { |
| flush_space(fs_info, space_info, to_reclaim, states[flush_state]); |
| flush_state++; |
| spin_lock(&space_info->lock); |
| if (ticket->bytes == 0) { |
| spin_unlock(&space_info->lock); |
| return; |
| } |
| spin_unlock(&space_info->lock); |
| } while (flush_state < states_nr); |
| } |
| |
| static void wait_reserve_ticket(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, |
| struct reserve_ticket *ticket) |
| |
| { |
| DEFINE_WAIT(wait); |
| int ret = 0; |
| |
| spin_lock(&space_info->lock); |
| while (ticket->bytes > 0 && ticket->error == 0) { |
| ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE); |
| if (ret) { |
| ticket->error = -EINTR; |
| break; |
| } |
| spin_unlock(&space_info->lock); |
| |
| schedule(); |
| |
| finish_wait(&ticket->wait, &wait); |
| spin_lock(&space_info->lock); |
| } |
| spin_unlock(&space_info->lock); |
| } |
| |
| /** |
| * handle_reserve_ticket - do the appropriate flushing and waiting for a ticket |
| * @fs_info - the fs |
| * @space_info - the space_info for the reservation |
| * @ticket - the ticket for the reservation |
| * @flush - how much we can flush |
| * |
| * This does the work of figuring out how to flush for the ticket, waiting for |
| * the reservation, and returning the appropriate error if there is one. |
| */ |
| static int handle_reserve_ticket(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, |
| struct reserve_ticket *ticket, |
| enum btrfs_reserve_flush_enum flush) |
| { |
| u64 reclaim_bytes = 0; |
| int ret; |
| |
| switch (flush) { |
| case BTRFS_RESERVE_FLUSH_ALL: |
| wait_reserve_ticket(fs_info, space_info, ticket); |
| break; |
| case BTRFS_RESERVE_FLUSH_LIMIT: |
| priority_reclaim_metadata_space(fs_info, space_info, ticket, |
| priority_flush_states, |
| ARRAY_SIZE(priority_flush_states)); |
| break; |
| case BTRFS_RESERVE_FLUSH_EVICT: |
| priority_reclaim_metadata_space(fs_info, space_info, ticket, |
| evict_flush_states, |
| ARRAY_SIZE(evict_flush_states)); |
| break; |
| default: |
| ASSERT(0); |
| break; |
| } |
| |
| spin_lock(&space_info->lock); |
| ret = ticket->error; |
| if (ticket->bytes || ticket->error) { |
| if (ticket->bytes < ticket->orig_bytes) |
| reclaim_bytes = ticket->orig_bytes - ticket->bytes; |
| list_del_init(&ticket->list); |
| if (!ret) |
| ret = -ENOSPC; |
| } |
| spin_unlock(&space_info->lock); |
| |
| if (reclaim_bytes) |
| btrfs_space_info_add_old_bytes(fs_info, space_info, |
| reclaim_bytes); |
| ASSERT(list_empty(&ticket->list)); |
| return ret; |
| } |
| |
| /** |
| * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space |
| * @root - the root we're allocating for |
| * @space_info - the space info we want to allocate from |
| * @orig_bytes - the number of bytes we want |
| * @flush - whether or not we can flush to make our reservation |
| * |
| * This will reserve orig_bytes number of bytes from the space info associated |
| * with the block_rsv. If there is not enough space it will make an attempt to |
| * flush out space to make room. It will do this by flushing delalloc if |
| * possible or committing the transaction. If flush is 0 then no attempts to |
| * regain reservations will be made and this will fail if there is not enough |
| * space already. |
| */ |
| static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info, |
| struct btrfs_space_info *space_info, |
| u64 orig_bytes, |
| enum btrfs_reserve_flush_enum flush, |
| bool system_chunk) |
| { |
| struct reserve_ticket ticket; |
| u64 used; |
| int ret = 0; |
| bool pending_tickets; |
| |
| ASSERT(orig_bytes); |
| ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL); |
| |
| spin_lock(&space_info->lock); |
| ret = -ENOSPC; |
| used = btrfs_space_info_used(space_info, true); |
| pending_tickets = !list_empty(&space_info->tickets) || |
| !list_empty(&space_info->priority_tickets); |
| |
| /* |
| * Carry on if we have enough space (short-circuit) OR call |
| * can_overcommit() to ensure we can overcommit to continue. |
| */ |
| if (!pending_tickets && |
| ((used + orig_bytes <= space_info->total_bytes) || |
| can_overcommit(fs_info, space_info, orig_bytes, flush, |
| system_chunk))) { |
| btrfs_space_info_update_bytes_may_use(fs_info, space_info, |
| orig_bytes); |
| trace_btrfs_space_reservation(fs_info, "space_info", |
| space_info->flags, orig_bytes, 1); |
| ret = 0; |
| } |
| |
| /* |
| * If we couldn't make a reservation then setup our reservation ticket |
| * and kick the async worker if it's not already running. |
| * |
| * If we are a priority flusher then we just need to add our ticket to |
| * the list and we will do our own flushing further down. |
| */ |
| if (ret && flush != BTRFS_RESERVE_NO_FLUSH) { |
| ticket.orig_bytes = orig_bytes; |
| ticket.bytes = orig_bytes; |
| ticket.error = 0; |
| init_waitqueue_head(&ticket.wait); |
| if (flush == BTRFS_RESERVE_FLUSH_ALL) { |
| list_add_tail(&ticket.list, &space_info->tickets); |
| if (!space_info->flush) { |
| space_info->flush = 1; |
| trace_btrfs_trigger_flush(fs_info, |
| space_info->flags, |
| orig_bytes, flush, |
| "enospc"); |
| queue_work(system_unbound_wq, |
| &fs_info->async_reclaim_work); |
| } |
| } else { |
| list_add_tail(&ticket.list, |
| &space_info->priority_tickets); |
| } |
| } else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) { |
| used += orig_bytes; |
| /* |
| * We will do the space reservation dance during log replay, |
| * which means we won't have fs_info->fs_root set, so don't do |
| * the async reclaim as we will panic. |
| */ |
| if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) && |
| need_do_async_reclaim(fs_info, space_info, |
| used, system_chunk) && |
| !work_busy(&fs_info->async_reclaim_work)) { |
| trace_btrfs_trigger_flush(fs_info, space_info->flags, |
| orig_bytes, flush, "preempt"); |
| queue_work(system_unbound_wq, |
| &fs_info->async_reclaim_work); |
| } |
| } |
| spin_unlock(&space_info->lock); |
| if (!ret || flush == BTRFS_RESERVE_NO_FLUSH) |
| return ret; |
| |
| return handle_reserve_ticket(fs_info, space_info, &ticket, flush); |
| } |
| |
| /** |
| * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space |
| * @root - the root we're allocating for |
| * @block_rsv - the block_rsv we're allocating for |
| * @orig_bytes - the number of bytes we want |
| * @flush - whether or not we can flush to make our reservation |
| * |
| * This will reserve orig_bytes number of bytes from the space info associated |
| * with the block_rsv. If there is not enough space it will make an attempt to |
| * flush out space to make room. It will do this by flushing delalloc if |
| * possible or committing the transaction. If flush is 0 then no attempts to |
| * regain reservations will be made and this will fail if there is not enough |
| * space already. |
| */ |
| int btrfs_reserve_metadata_bytes(struct btrfs_root *root, |
| struct btrfs_block_rsv *block_rsv, |
| u64 orig_bytes, |
| enum btrfs_reserve_flush_enum flush) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; |
| int ret; |
| bool system_chunk = (root == fs_info->chunk_root); |
| |
| ret = __reserve_metadata_bytes(fs_info, block_rsv->space_info, |
| orig_bytes, flush, system_chunk); |
| if (ret == -ENOSPC && |
| unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) { |
| if (block_rsv != global_rsv && |
| !btrfs_block_rsv_use_bytes(global_rsv, orig_bytes)) |
| ret = 0; |
| } |
| if (ret == -ENOSPC) { |
| trace_btrfs_space_reservation(fs_info, "space_info:enospc", |
| block_rsv->space_info->flags, |
| orig_bytes, 1); |
| |
| if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) |
| btrfs_dump_space_info(fs_info, block_rsv->space_info, |
| orig_bytes, 0); |
| } |
| return ret; |
| } |