diff options
Diffstat (limited to 'fs/btrfs/extent-tree.c')
| -rw-r--r-- | fs/btrfs/extent-tree.c | 541 |
1 files changed, 328 insertions, 213 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 47c1ba141082..8b353ad02f03 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -74,8 +74,9 @@ enum { RESERVE_ALLOC_NO_ACCOUNT = 2, }; -static int update_block_group(struct btrfs_root *root, - u64 bytenr, u64 num_bytes, int alloc); +static int update_block_group(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 bytenr, + u64 num_bytes, int alloc); static int __btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, u64 parent, @@ -315,12 +316,6 @@ get_caching_control(struct btrfs_block_group_cache *cache) struct btrfs_caching_control *ctl; spin_lock(&cache->lock); - if (cache->cached != BTRFS_CACHE_STARTED) { - spin_unlock(&cache->lock); - return NULL; - } - - /* We're loading it the fast way, so we don't have a caching_ctl. */ if (!cache->caching_ctl) { spin_unlock(&cache->lock); return NULL; @@ -594,6 +589,7 @@ static int cache_block_group(struct btrfs_block_group_cache *cache, spin_unlock(&cache->lock); if (fs_info->mount_opt & BTRFS_MOUNT_SPACE_CACHE) { + mutex_lock(&caching_ctl->mutex); ret = load_free_space_cache(fs_info, cache); spin_lock(&cache->lock); @@ -601,15 +597,19 @@ static int cache_block_group(struct btrfs_block_group_cache *cache, cache->caching_ctl = NULL; cache->cached = BTRFS_CACHE_FINISHED; cache->last_byte_to_unpin = (u64)-1; + caching_ctl->progress = (u64)-1; } else { if (load_cache_only) { cache->caching_ctl = NULL; cache->cached = BTRFS_CACHE_NO; } else { cache->cached = BTRFS_CACHE_STARTED; + cache->has_caching_ctl = 1; } } spin_unlock(&cache->lock); + mutex_unlock(&caching_ctl->mutex); + wake_up(&caching_ctl->wait); if (ret == 1) { put_caching_control(caching_ctl); @@ -627,6 +627,7 @@ static int cache_block_group(struct btrfs_block_group_cache *cache, cache->cached = BTRFS_CACHE_NO; } else { cache->cached = BTRFS_CACHE_STARTED; + cache->has_caching_ctl = 1; } spin_unlock(&cache->lock); wake_up(&caching_ctl->wait); @@ -1889,8 +1890,8 @@ static int btrfs_issue_discard(struct block_device *bdev, return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0); } -static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, - u64 num_bytes, u64 *actual_bytes) +int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, + u64 num_bytes, u64 *actual_bytes) { int ret; u64 discarded_bytes = 0; @@ -1925,7 +1926,7 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, */ ret = 0; } - kfree(bbio); + btrfs_put_bbio(bbio); } if (actual_bytes) @@ -2768,7 +2769,6 @@ int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_head *head; int ret; int run_all = count == (unsigned long)-1; - int run_most = 0; /* We'll clean this up in btrfs_cleanup_transaction */ if (trans->aborted) @@ -2778,10 +2778,8 @@ int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, root = root->fs_info->tree_root; delayed_refs = &trans->transaction->delayed_refs; - if (count == 0) { + if (count == 0) count = atomic_read(&delayed_refs->num_entries) * 2; - run_most = 1; - } again: #ifdef SCRAMBLE_DELAYED_REFS @@ -3139,9 +3137,11 @@ static int write_one_cache_group(struct btrfs_trans_handle *trans, struct extent_buffer *leaf; ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1); - if (ret < 0) + if (ret) { + if (ret > 0) + ret = -ENOENT; goto fail; - BUG_ON(ret); /* Corruption */ + } leaf = path->nodes[0]; bi = btrfs_item_ptr_offset(leaf, path->slots[0]); @@ -3149,11 +3149,9 @@ static int write_one_cache_group(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(leaf); btrfs_release_path(path); fail: - if (ret) { + if (ret) btrfs_abort_transaction(trans, root, ret); - return ret; - } - return 0; + return ret; } @@ -3162,7 +3160,19 @@ next_block_group(struct btrfs_root *root, struct btrfs_block_group_cache *cache) { struct rb_node *node; + spin_lock(&root->fs_info->block_group_cache_lock); + + /* If our block group was removed, we need a full search. */ + if (RB_EMPTY_NODE(&cache->cache_node)) { + const u64 next_bytenr = cache->key.objectid + cache->key.offset; + + spin_unlock(&root->fs_info->block_group_cache_lock); + btrfs_put_block_group(cache); + cache = btrfs_lookup_first_block_group(root->fs_info, + next_bytenr); + return cache; + } node = rb_next(&cache->cache_node); btrfs_put_block_group(cache); if (node) { @@ -3198,6 +3208,8 @@ static int cache_save_setup(struct btrfs_block_group_cache *block_group, return 0; } + if (trans->aborted) + return 0; again: inode = lookup_free_space_inode(root, block_group, path); if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) { @@ -3233,6 +3245,20 @@ again: */ BTRFS_I(inode)->generation = 0; ret = btrfs_update_inode(trans, root, inode); + if (ret) { + /* + * So theoretically we could recover from this, simply set the + * super cache generation to 0 so we know to invalidate the + * cache, but then we'd have to keep track of the block groups + * that fail this way so we know we _have_ to reset this cache + * before the next commit or risk reading stale cache. So to + * limit our exposure to horrible edge cases lets just abort the + * transaction, this only happens in really bad situations + * anyway. + */ + btrfs_abort_transaction(trans, root, ret); + goto out_put; + } WARN_ON(ret); if (i_size_read(inode) > 0) { @@ -3299,124 +3325,72 @@ out: return ret; } -int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, - struct btrfs_root *root) +int btrfs_setup_space_cache(struct btrfs_trans_handle *trans, + struct btrfs_root *root) { - struct btrfs_block_group_cache *cache; - int err = 0; + struct btrfs_block_group_cache *cache, *tmp; + struct btrfs_transaction *cur_trans = trans->transaction; struct btrfs_path *path; - u64 last = 0; + + if (list_empty(&cur_trans->dirty_bgs) || + !btrfs_test_opt(root, SPACE_CACHE)) + return 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; -again: - while (1) { - cache = btrfs_lookup_first_block_group(root->fs_info, last); - while (cache) { - if (cache->disk_cache_state == BTRFS_DC_CLEAR) - break; - cache = next_block_group(root, cache); - } - if (!cache) { - if (last == 0) - break; - last = 0; - continue; - } - err = cache_save_setup(cache, trans, path); - last = cache->key.objectid + cache->key.offset; - btrfs_put_block_group(cache); + /* Could add new block groups, use _safe just in case */ + list_for_each_entry_safe(cache, tmp, &cur_trans->dirty_bgs, + dirty_list) { + if (cache->disk_cache_state == BTRFS_DC_CLEAR) + cache_save_setup(cache, trans, path); } - while (1) { - if (last == 0) { - err = btrfs_run_delayed_refs(trans, root, - (unsigned long)-1); - if (err) /* File system offline */ - goto out; - } - - cache = btrfs_lookup_first_block_group(root->fs_info, last); - while (cache) { - if (cache->disk_cache_state == BTRFS_DC_CLEAR) { - btrfs_put_block_group(cache); - goto again; - } - - if (cache->dirty) - break; - cache = next_block_group(root, cache); - } - if (!cache) { - if (last == 0) - break; - last = 0; - continue; - } - - if (cache->disk_cache_state == BTRFS_DC_SETUP) - cache->disk_cache_state = BTRFS_DC_NEED_WRITE; - cache->dirty = 0; - last = cache->key.objectid + cache->key.offset; - - err = write_one_cache_group(trans, root, path, cache); - btrfs_put_block_group(cache); - if (err) /* File system offline */ - goto out; - } + btrfs_free_path(path); + return 0; +} - while (1) { - /* - * I don't think this is needed since we're just marking our - * preallocated extent as written, but just in case it can't - * hurt. - */ - if (last == 0) { - err = btrfs_run_delayed_refs(trans, root, - (unsigned long)-1); - if (err) /* File system offline */ - goto out; - } +int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, + struct btrfs_root *root) +{ + struct btrfs_block_group_cache *cache; + struct btrfs_transaction *cur_trans = trans->transaction; + int ret = 0; + struct btrfs_path *path; - cache = btrfs_lookup_first_block_group(root->fs_info, last); - while (cache) { - /* - * Really this shouldn't happen, but it could if we - * couldn't write the entire preallocated extent and - * splitting the extent resulted in a new block. - */ - if (cache->dirty) { - btrfs_put_block_group(cache); - goto again; - } - if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE) - break; - cache = next_block_group(root, cache); - } - if (!cache) { - if (last == 0) - break; - last = 0; - continue; - } + if (list_empty(&cur_trans->dirty_bgs)) + return 0; - err = btrfs_write_out_cache(root, trans, cache, path); + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; - /* - * If we didn't have an error then the cache state is still - * NEED_WRITE, so we can set it to WRITTEN. - */ - if (!err && cache->disk_cache_state == BTRFS_DC_NEED_WRITE) - cache->disk_cache_state = BTRFS_DC_WRITTEN; - last = cache->key.objectid + cache->key.offset; + /* + * We don't need the lock here since we are protected by the transaction + * commit. We want to do the cache_save_setup first and then run the + * delayed refs to make sure we have the best chance at doing this all + * in one shot. + */ + while (!list_empty(&cur_trans->dirty_bgs)) { + cache = list_first_entry(&cur_trans->dirty_bgs, + struct btrfs_block_group_cache, + dirty_list); + list_del_init(&cache->dirty_list); + if (cache->disk_cache_state == BTRFS_DC_CLEAR) + cache_save_setup(cache, trans, path); + if (!ret) + ret = btrfs_run_delayed_refs(trans, root, + (unsigned long) -1); + if (!ret && cache->disk_cache_state == BTRFS_DC_SETUP) + btrfs_write_out_cache(root, trans, cache, path); + if (!ret) + ret = write_one_cache_group(trans, root, path, cache); btrfs_put_block_group(cache); } -out: btrfs_free_path(path); - return err; + return ret; } int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr) @@ -3504,6 +3478,7 @@ static int update_space_info(struct btrfs_fs_info *info, u64 flags, found->chunk_alloc = 0; found->flush = 0; init_waitqueue_head(&found->wait); + INIT_LIST_HEAD(&found->ro_bgs); ret = kobject_init_and_add(&found->kobj, &space_info_ktype, info->space_info_kobj, "%s", @@ -5030,19 +5005,25 @@ void btrfs_subvolume_release_metadata(struct btrfs_root *root, /** * drop_outstanding_extent - drop an outstanding extent * @inode: the inode we're dropping the extent for + * @num_bytes: the number of bytes we're relaseing. * * This is called when we are freeing up an outstanding extent, either called * after an error or after an extent is written. This will return the number of * reserved extents that need to be freed. This must be called with * BTRFS_I(inode)->lock held. */ -static unsigned drop_outstanding_extent(struct inode *inode) +static unsigned drop_outstanding_extent(struct inode *inode, u64 num_bytes) { unsigned drop_inode_space = 0; unsigned dropped_extents = 0; + unsigned num_extents = 0; - BUG_ON(!BTRFS_I(inode)->outstanding_extents); - BTRFS_I(inode)->outstanding_extents--; + num_extents = (unsigned)div64_u64(num_bytes + + BTRFS_MAX_EXTENT_SIZE - 1, + BTRFS_MAX_EXTENT_SIZE); + ASSERT(num_extents); + ASSERT(BTRFS_I(inode)->outstanding_extents >= num_extents); + BTRFS_I(inode)->outstanding_extents -= num_extents; if (BTRFS_I(inode)->outstanding_extents == 0 && test_and_clear_bit(BTRFS_INODE_DELALLOC_META_RESERVED, @@ -5155,7 +5136,11 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes) num_bytes = ALIGN(num_bytes, root->sectorsize); spin_lock(&BTRFS_I(inode)->lock); - BTRFS_I(inode)->outstanding_extents++; + nr_extents = (unsigned)div64_u64(num_bytes + + BTRFS_MAX_EXTENT_SIZE - 1, + BTRFS_MAX_EXTENT_SIZE); + BTRFS_I(inode)->outstanding_extents += nr_extents; + nr_extents = 0; if (BTRFS_I(inode)->outstanding_extents > BTRFS_I(inode)->reserved_extents) @@ -5213,7 +5198,7 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes) out_fail: spin_lock(&BTRFS_I(inode)->lock); - dropped = drop_outstanding_extent(inode); + dropped = drop_outstanding_extent(inode, num_bytes); /* * If the inodes csum_bytes is the same as the original * csum_bytes then we know we haven't raced with any free()ers @@ -5292,7 +5277,7 @@ void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes) num_bytes = ALIGN(num_bytes, root->sectorsize); spin_lock(&BTRFS_I(inode)->lock); - dropped = drop_outstanding_extent(inode); + dropped = drop_outstanding_extent(inode, num_bytes); if (num_bytes) to_free = calc_csum_metadata_size(inode, num_bytes, 0); @@ -5300,6 +5285,9 @@ void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes) if (dropped > 0) to_free += btrfs_calc_trans_metadata_size(root, dropped); + if (btrfs_test_is_dummy_root(root)) + return; + trace_btrfs_space_reservation(root->fs_info, "delalloc", btrfs_ino(inode), to_free, 0); if (root->fs_info->quota_enabled) { @@ -5362,8 +5350,9 @@ void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes) btrfs_free_reserved_data_space(inode, num_bytes); } -static int update_block_group(struct btrfs_root *root, - u64 bytenr, u64 num_bytes, int alloc) +static int update_block_group(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 bytenr, + u64 num_bytes, int alloc) { struct btrfs_block_group_cache *cache = NULL; struct btrfs_fs_info *info = root->fs_info; @@ -5401,6 +5390,14 @@ static int update_block_group(struct btrfs_root *root, if (!alloc && cache->cached == BTRFS_CACHE_NO) cache_block_group(cache, 1); + spin_lock(&trans->transaction->dirty_bgs_lock); + if (list_empty(&cache->dirty_list)) { + list_add_tail(&cache->dirty_list, + &trans->transaction->dirty_bgs); + btrfs_get_block_group(cache); + } + spin_unlock(&trans->transaction->dirty_bgs_lock); + byte_in_group = bytenr - cache->key.objectid; WARN_ON(byte_in_group > cache->key.offset); @@ -5411,7 +5408,6 @@ static int update_block_group(struct btrfs_root *root, cache->disk_cache_state < BTRFS_DC_CLEAR) cache->disk_cache_state = BTRFS_DC_CLEAR; - cache->dirty = 1; old_val = btrfs_block_group_used(&cache->item); num_bytes = min(total, cache->key.offset - byte_in_group); if (alloc) { @@ -5425,7 +5421,17 @@ static int update_block_group(struct btrfs_root *root, spin_unlock(&cache->space_info->lock); } else { old_val -= num_bytes; + btrfs_set_block_group_used(&cache->item, old_val); + cache->pinned += num_bytes; + cache->space_info->bytes_pinned += num_bytes; + cache->space_info->bytes_used -= num_bytes; + cache->space_info->disk_used -= num_bytes * factor; + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); + set_extent_dirty(info->pinned_extents, + bytenr, bytenr + num_bytes - 1, + GFP_NOFS | __GFP_NOFAIL); /* * No longer have used bytes in this block group, queue * it for deletion. @@ -5439,17 +5445,6 @@ static int update_block_group(struct btrfs_root *root, } spin_unlock(&info->unused_bgs_lock); } - btrfs_set_block_group_used(&cache->item, old_val); - cache->pinned += num_bytes; - cache->space_info->bytes_pinned += num_bytes; - cache->space_info->bytes_used -= num_bytes; - cache->space_info->disk_used -= num_bytes * factor; - spin_unlock(&cache->lock); - spin_unlock(&cache->space_info->lock); - - set_extent_dirty(info->pinned_extents, - bytenr, bytenr + num_bytes - 1, - GFP_NOFS | __GFP_NOFAIL); } btrfs_put_block_group(cache); total -= num_bytes; @@ -5715,7 +5710,8 @@ void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans, update_global_block_rsv(fs_info); } -static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end) +static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end, + const bool return_free_space) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_block_group_cache *cache = NULL; @@ -5739,7 +5735,8 @@ static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end) if (start < cache->last_byte_to_unpin) { len = min(len, cache->last_byte_to_unpin - start); - btrfs_add_free_space(cache, start, len); + if (return_free_space) + btrfs_add_free_space(cache, start, len); } start += len; @@ -5793,17 +5790,21 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, unpin = &fs_info->freed_extents[0]; while (1) { + mutex_lock(&fs_info->unused_bg_unpin_mutex); ret = find_first_extent_bit(unpin, 0, &start, &end, EXTENT_DIRTY, NULL); - if (ret) + if (ret) { + mutex_unlock(&fs_info->unused_bg_unpin_mutex); break; + } if (btrfs_test_opt(root, DISCARD)) ret = btrfs_discard_extent(root, start, end + 1 - start, NULL); clear_extent_dirty(unpin, start, end, GFP_NOFS); - unpin_extent_range(root, start, end); + unpin_extent_range(root, start, end, true); + mutex_unlock(&fs_info->unused_bg_unpin_mutex); cond_resched(); } @@ -6089,7 +6090,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans, } } - ret = update_block_group(root, bytenr, num_bytes, 0); + ret = update_block_group(trans, root, bytenr, num_bytes, 0); if (ret) { btrfs_abort_transaction(trans, extent_root, ret); goto out; @@ -6191,7 +6192,6 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, struct extent_buffer *buf, u64 parent, int last_ref) { - struct btrfs_block_group_cache *cache = NULL; int pin = 1; int ret; @@ -6207,17 +6207,20 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, if (!last_ref) return; - cache = btrfs_lookup_block_group(root->fs_info, buf->start); - if (btrfs_header_generation(buf) == trans->transid) { + struct btrfs_block_group_cache *cache; + if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { ret = check_ref_cleanup(trans, root, buf->start); if (!ret) goto out; } + cache = btrfs_lookup_block_group(root->fs_info, buf->start); + if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { pin_down_extent(root, cache, buf->start, buf->len, 1); + btrfs_put_block_group(cache); goto out; } @@ -6225,6 +6228,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, btrfs_add_free_space(cache, buf->start, buf->len); btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE, 0); + btrfs_put_block_group(cache); trace_btrfs_reserved_extent_free(root, buf->start, buf->len); pin = 0; } @@ -6239,7 +6243,6 @@ out: * anymore. */ clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags); - btrfs_put_block_group(cache); } /* Can return -ENOMEM */ @@ -7049,7 +7052,7 @@ static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans, if (ret) return ret; - ret = update_block_group(root, ins->objectid, ins->offset, 1); + ret = update_block_group(trans, root, ins->objectid, ins->offset, 1); if (ret) { /* -ENOENT, logic error */ btrfs_err(fs_info, "update block group failed for %llu %llu", ins->objectid, ins->offset); @@ -7138,7 +7141,8 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans, return ret; } - ret = update_block_group(root, ins->objectid, root->nodesize, 1); + ret = update_block_group(trans, root, ins->objectid, root->nodesize, + 1); if (ret) { /* -ENOENT, logic error */ btrfs_err(fs_info, "update block group failed for %llu %llu", ins->objectid, ins->offset); @@ -7203,11 +7207,11 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans, static struct extent_buffer * btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root, - u64 bytenr, u32 blocksize, int level) + u64 bytenr, int level) { struct extent_buffer *buf; - buf = btrfs_find_create_tree_block(root, bytenr, blocksize); + buf = btrfs_find_create_tree_block(root, bytenr); if (!buf) return ERR_PTR(-ENOMEM); btrfs_set_header_generation(buf, trans->transid); @@ -7326,7 +7330,7 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans, if (btrfs_test_is_dummy_root(root)) { buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr, - blocksize, level); + level); if (!IS_ERR(buf)) root->alloc_bytenr += blocksize; return buf; @@ -7343,8 +7347,7 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans, return ERR_PTR(ret); } - buf = btrfs_init_new_buffer(trans, root, ins.objectid, - blocksize, level); + buf = btrfs_init_new_buffer(trans, root, ins.objectid, level); BUG_ON(IS_ERR(buf)); /* -ENOMEM */ if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) { @@ -7473,7 +7476,7 @@ static noinline void reada_walk_down(struct btrfs_trans_handle *trans, continue; } reada: - readahead_tree_block(root, bytenr, blocksize); + readahead_tree_block(root, bytenr); nread++; } wc->reada_slot = slot; @@ -7814,7 +7817,7 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans, next = btrfs_find_tree_block(root, bytenr); if (!next) { - next = btrfs_find_create_tree_block(root, bytenr, blocksize); + next = btrfs_find_create_tree_block(root, bytenr); if (!next) return -ENOMEM; btrfs_set_buffer_lockdep_class(root->root_key.objectid, next, @@ -8511,6 +8514,7 @@ static int set_block_group_ro(struct btrfs_block_group_cache *cache, int force) min_allocable_bytes <= sinfo->total_bytes) { sinfo->bytes_readonly += num_bytes; cache->ro = 1; + list_add_tail(&cache->ro_list, &sinfo->ro_bgs); ret = 0; } out: @@ -8533,14 +8537,6 @@ int btrfs_set_block_group_ro(struct btrfs_root *root, if (IS_ERR(trans)) return PTR_ERR(trans); - alloc_flags = update_block_group_flags(root, cache->flags); - if (alloc_flags != cache->flags) { - ret = do_chunk_alloc(trans, root, alloc_flags, - CHUNK_ALLOC_FORCE); - if (ret < 0) - goto out; - } - ret = set_block_group_ro(cache, 0); if (!ret) goto out; @@ -8551,6 +8547,11 @@ int btrfs_set_block_group_ro(struct btrfs_root *root, goto out; ret = set_block_group_ro(cache, 0); out: + if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) { + alloc_flags = update_block_group_flags(root, cache->flags); + check_system_chunk(trans, root, alloc_flags); + } + btrfs_end_transaction(trans, root); return ret; } @@ -8565,15 +8566,20 @@ int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, /* * helper to account the unused space of all the readonly block group in the - * list. takes mirrors into account. + * space_info. takes mirrors into account. */ -static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list) +u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo) { struct btrfs_block_group_cache *block_group; u64 free_bytes = 0; int factor; - list_for_each_entry(block_group, groups_list, list) { + /* It's df, we don't care if it's racey */ + if (list_empty(&sinfo->ro_bgs)) + return 0; + + spin_lock(&sinfo->lock); + list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) { spin_lock(&block_group->lock); if (!block_group->ro) { @@ -8594,26 +8600,6 @@ static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list) spin_unlock(&block_group->lock); } - - return free_bytes; -} - -/* - * helper to account the unused space of all the readonly block group in the - * space_info. takes mirrors into account. - */ -u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo) -{ - int i; - u64 free_bytes = 0; - - spin_lock(&sinfo->lock); - - for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) - if (!list_empty(&sinfo->block_groups[i])) - free_bytes += __btrfs_get_ro_block_group_free_space( - &sinfo->block_groups[i]); - spin_unlock(&sinfo->lock); return free_bytes; @@ -8633,6 +8619,7 @@ void btrfs_set_block_group_rw(struct btrfs_root *root, cache->bytes_super - btrfs_block_group_used(&cache->item); sinfo->bytes_readonly -= num_bytes; cache->ro = 0; + list_del_init(&cache->ro_list); spin_unlock(&cache->lock); spin_unlock(&sinfo->lock); } @@ -8873,6 +8860,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info) cache_node); rb_erase(&block_group->cache_node, &info->block_group_cache_tree); + RB_CLEAR_NODE(&block_group->cache_node); spin_unlock(&info->block_group_cache_lock); down_write(&block_group->space_info->groups_sem); @@ -9002,7 +8990,10 @@ btrfs_create_block_group_cache(struct btrfs_root *root, u64 start, u64 size) INIT_LIST_HEAD(&cache->list); INIT_LIST_HEAD(&cache->cluster_list); INIT_LIST_HEAD(&cache->bg_list); + INIT_LIST_HEAD(&cache->ro_list); + INIT_LIST_HEAD(&cache->dirty_list); btrfs_init_free_space_ctl(cache); + atomic_set(&cache->trimming, 0); return cache; } @@ -9064,9 +9055,8 @@ int btrfs_read_block_groups(struct btrfs_root *root) * b) Setting 'dirty flag' makes sure that we flush * the new space cache info onto disk. */ - cache->disk_cache_state = BTRFS_DC_CLEAR; if (btrfs_test_opt(root, SPACE_CACHE)) - cache->dirty = 1; + cache->disk_cache_state = BTRFS_DC_CLEAR; } read_extent_buffer(leaf, &cache->item, @@ -9129,6 +9119,7 @@ int btrfs_read_block_groups(struct btrfs_root *root) spin_lock(&info->block_group_cache_lock); rb_erase(&cache->cache_node, &info->block_group_cache_tree); + RB_CLEAR_NODE(&cache->cache_node); spin_unlock(&info->block_group_cache_lock); btrfs_put_block_group(cache); goto error; @@ -9195,9 +9186,8 @@ void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans, int ret = 0; list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) { - list_del_init(&block_group->bg_list); if (ret) - continue; + goto next; spin_lock(&block_group->lock); memcpy(&item, &block_group->item, sizeof(item)); @@ -9212,6 +9202,8 @@ void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans, key.objectid, key.offset); if (ret) btrfs_abort_transaction(trans, extent_root, ret); +next: + list_del_init(&block_group->bg_list); } } @@ -9269,6 +9261,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, spin_lock(&root->fs_info->block_group_cache_lock); rb_erase(&cache->cache_node, &root->fs_info->block_group_cache_tree); + RB_CLEAR_NODE(&cache->cache_node); spin_unlock(&root->fs_info->block_group_cache_lock); btrfs_put_block_group(cache); return ret; @@ -9304,7 +9297,8 @@ static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) } int btrfs_remove_block_group(struct btrfs_trans_handle *trans, - struct btrfs_root *root, u64 group_start) + struct btrfs_root *root, u64 group_start, + struct extent_map *em) { struct btrfs_path *path; struct btrfs_block_group_cache *block_group; @@ -9316,6 +9310,8 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, int ret; int index; int factor; + struct btrfs_caching_control *caching_ctl = NULL; + bool remove_em; root = root->fs_info->extent_root; @@ -9400,6 +9396,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, spin_lock(&root->fs_info->block_group_cache_lock); rb_erase(&block_group->cache_node, &root->fs_info->block_group_cache_tree); + RB_CLEAR_NODE(&block_group->cache_node); if (root->fs_info->first_logical_byte == block_group->key.objectid) root->fs_info->first_logical_byte = (u64)-1; @@ -9422,12 +9419,44 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, kobject_put(kobj); } + if (block_group->has_caching_ctl) + caching_ctl = get_caching_control(block_group); if (block_group->cached == BTRFS_CACHE_STARTED) wait_block_group_cache_done(block_group); + if (block_group->has_caching_ctl) { + down_write(&root->fs_info->commit_root_sem); + if (!caching_ctl) { + struct btrfs_caching_control *ctl; + + list_for_each_entry(ctl, + &root->fs_info->caching_block_groups, list) + if (ctl->block_group == block_group) { + caching_ctl = ctl; + atomic_inc(&caching_ctl->count); + break; + } + } + if (caching_ctl) + list_del_init(&caching_ctl->list); + up_write(&root->fs_info->commit_root_sem); + if (caching_ctl) { + /* Once for the caching bgs list and once for us. */ + put_caching_control(caching_ctl); + put_caching_control(caching_ctl); + } + } + + spin_lock(&trans->transaction->dirty_bgs_lock); + if (!list_empty(&block_group->dirty_list)) { + list_del_init(&block_group->dirty_list); + btrfs_put_block_group(block_group); + } + 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); 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; @@ -9435,6 +9464,71 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, memcpy(&key, &block_group->key, sizeof(key)); + lock_chunks(root); + if (!list_empty(&em->list)) { + /* We're in the transaction->pending_chunks list. */ + free_extent_map(em); + } + 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. + */ + remove_em = (atomic_read(&block_group->trimming) == 0); + /* + * Make sure a trimmer task always sees the em in the pinned_chunks list + * if it sees block_group->removed == 1 (needs to lock block_group->lock + * before checking block_group->removed). + */ + if (!remove_em) { + /* + * Our em might be in trans->transaction->pending_chunks which + * is protected by fs_info->chunk_mutex ([lock|unlock]_chunks), + * and so is the fs_info->pinned_chunks list. + * + * So at this point we must be holding the chunk_mutex to avoid + * any races with chunk allocation (more specifically at + * volumes.c:contains_pending_extent()), to ensure it always + * sees the em, either in the pending_chunks list or in the + * pinned_chunks list. + */ + list_move_tail(&em->list, &root->fs_info->pinned_chunks); + } + spin_unlock(&block_group->lock); + + if (remove_em) { + struct extent_map_tree *em_tree; + + em_tree = &root->fs_info->mapping_tree.map_tree; + write_lock(&em_tree->lock); + /* + * The em might be in the pending_chunks list, so make sure the + * chunk mutex is locked, since remove_extent_mapping() will + * delete us from that list. + */ + remove_extent_mapping(em_tree, em); + write_unlock(&em_tree->lock); + /* once for the tree */ + free_extent_map(em); + } + + unlock_chunks(root); + btrfs_put_block_group(block_group); btrfs_put_block_group(block_group); @@ -9510,7 +9604,8 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) * Want to do this before we do anything else so we can recover * properly if we fail to join the transaction. */ - trans = btrfs_join_transaction(root); + /* 1 for btrfs_orphan_reserve_metadata() */ + trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { btrfs_set_block_group_rw(root, block_group); ret = PTR_ERR(trans); @@ -9523,10 +9618,33 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) */ start = block_group->key.objectid; end = start + block_group->key.offset - 1; - clear_extent_bits(&fs_info->freed_extents[0], start, end, + /* + * 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, GFP_NOFS); - clear_extent_bits(&fs_info->freed_extents[1], start, end, + if (ret) { + mutex_unlock(&fs_info->unused_bg_unpin_mutex); + btrfs_set_block_group_rw(root, block_group); + goto end_trans; + } + ret = clear_extent_bits(&fs_info->freed_extents[1], start, end, EXTENT_DIRTY, GFP_NOFS); + if (ret) { + mutex_unlock(&fs_info->unused_bg_unpin_mutex); + btrfs_set_block_group_rw(root, block_group); + goto end_trans; + } + mutex_unlock(&fs_info->unused_bg_unpin_mutex); /* Reset pinned so btrfs_put_block_group doesn't complain */ block_group->pinned = 0; @@ -9537,6 +9655,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) */ ret = btrfs_remove_chunk(trans, root, block_group->key.objectid); +end_trans: btrfs_end_transaction(trans, root); next: btrfs_put_block_group(block_group); @@ -9585,13 +9704,7 @@ out: int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end) { - return unpin_extent_range(root, start, end); -} - -int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr, - u64 num_bytes, u64 *actual_bytes) -{ - return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes); + return unpin_extent_range(root, start, end, false); } int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range) @@ -9657,12 +9770,14 @@ int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range) } /* - * btrfs_{start,end}_write() is similar to mnt_{want, drop}_write(), - * they are used to prevent the some tasks writing data into the page cache - * by nocow before the subvolume is snapshoted, but flush the data into - * the disk after the snapshot creation. + * btrfs_{start,end}_write_no_snapshoting() are similar to + * mnt_{want,drop}_write(), they are used to prevent some tasks from writing + * data into the page cache through nocow before the subvolume is snapshoted, + * but flush the data into disk after the snapshot creation, or to prevent + * operations while snapshoting is ongoing and that cause the snapshot to be + * inconsistent (writes followed by expanding truncates for example). */ -void btrfs_end_nocow_write(struct btrfs_root *root) +void btrfs_end_write_no_snapshoting(struct btrfs_root *root) { percpu_counter_dec(&root->subv_writers->counter); /* @@ -9674,7 +9789,7 @@ void btrfs_end_nocow_write(struct btrfs_root *root) wake_up(&root->subv_writers->wait); } -int btrfs_start_nocow_write(struct btrfs_root *root) +int btrfs_start_write_no_snapshoting(struct btrfs_root *root) { if (atomic_read(&root->will_be_snapshoted)) return 0; @@ -9685,7 +9800,7 @@ int btrfs_start_nocow_write(struct btrfs_root *root) */ smp_mb(); if (atomic_read(&root->will_be_snapshoted)) { - btrfs_end_nocow_write(root); + btrfs_end_write_no_snapshoting(root); return 0; } return 1; |