diff options
author | Chris Mason <clm@fb.com> | 2015-08-09 14:35:33 (GMT) |
---|---|---|
committer | Chris Mason <clm@fb.com> | 2015-08-09 14:35:33 (GMT) |
commit | 46cd28555ffaa40162290dba203daad0ff6f7abd (patch) | |
tree | a10fd81b6c7ff5ea7642b1e2462e529971e8713a | |
parent | da2f0f74cf7d074e5a8918c8efdf6aba4a989b4a (diff) | |
parent | e33e17ee1098d8d751552ac11c111e1c1a3db014 (diff) | |
download | linux-46cd28555ffaa40162290dba203daad0ff6f7abd.tar.xz |
Merge branch 'jeffm-discard-4.3' into for-linus-4.3
-rw-r--r-- | fs/btrfs/ctree.h | 3 | ||||
-rw-r--r-- | fs/btrfs/disk-io.c | 9 | ||||
-rw-r--r-- | fs/btrfs/extent-tree.c | 248 | ||||
-rw-r--r-- | fs/btrfs/free-space-cache.c | 57 | ||||
-rw-r--r-- | fs/btrfs/super.c | 13 | ||||
-rw-r--r-- | fs/btrfs/transaction.c | 2 | ||||
-rw-r--r-- | fs/btrfs/transaction.h | 2 | ||||
-rw-r--r-- | fs/btrfs/volumes.c | 63 | ||||
-rw-r--r-- | fs/btrfs/volumes.h | 3 |
9 files changed, 342 insertions, 58 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index d4042c8..938efe3 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3431,6 +3431,8 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, struct btrfs_root *root, 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, struct btrfs_root *root); u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data); @@ -4067,6 +4069,7 @@ __cold void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function, unsigned int line, int errno, const char *fmt, ...); +const char *btrfs_decode_error(int errno); __cold void __btrfs_abort_transaction(struct btrfs_trans_handle *trans, diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 230546b..cc15514b 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3761,6 +3761,15 @@ void close_ctree(struct btrfs_root *root) cancel_work_sync(&fs_info->async_reclaim_work); if (!(fs_info->sb->s_flags & MS_RDONLY)) { + /* + * If the cleaner thread is stopped and there are + * block groups queued for removal, the deletion will be + * skipped when we quit the cleaner thread. + */ + mutex_lock(&root->fs_info->cleaner_mutex); + btrfs_delete_unused_bgs(root->fs_info); + mutex_unlock(&root->fs_info->cleaner_mutex); + ret = btrfs_commit_super(root); if (ret) btrfs_err(fs_info, "commit super ret %d", ret); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 59d59d9..5411f0a 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -1882,10 +1882,77 @@ static int remove_extent_backref(struct btrfs_trans_handle *trans, return ret; } -static int btrfs_issue_discard(struct block_device *bdev, - u64 start, u64 len) +#define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len)) +static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len, + u64 *discarded_bytes) { - return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0); + int j, ret = 0; + u64 bytes_left, end; + u64 aligned_start = ALIGN(start, 1 << 9); + + if (WARN_ON(start != aligned_start)) { + len -= aligned_start - start; + len = round_down(len, 1 << 9); + start = aligned_start; + } + + *discarded_bytes = 0; + + if (!len) + return 0; + + end = start + len; + bytes_left = len; + + /* Skip any superblocks on this device. */ + for (j = 0; j < BTRFS_SUPER_MIRROR_MAX; j++) { + u64 sb_start = btrfs_sb_offset(j); + u64 sb_end = sb_start + BTRFS_SUPER_INFO_SIZE; + u64 size = sb_start - start; + + if (!in_range(sb_start, start, bytes_left) && + !in_range(sb_end, start, bytes_left) && + !in_range(start, sb_start, BTRFS_SUPER_INFO_SIZE)) + continue; + + /* + * Superblock spans beginning of range. Adjust start and + * try again. + */ + if (sb_start <= start) { + start += sb_end - start; + if (start > end) { + bytes_left = 0; + break; + } + bytes_left = end - start; + continue; + } + + if (size) { + ret = blkdev_issue_discard(bdev, start >> 9, size >> 9, + GFP_NOFS, 0); + if (!ret) + *discarded_bytes += size; + else if (ret != -EOPNOTSUPP) + return ret; + } + + start = sb_end; + if (start > end) { + bytes_left = 0; + break; + } + bytes_left = end - start; + } + + if (bytes_left) { + ret = blkdev_issue_discard(bdev, start >> 9, bytes_left >> 9, + GFP_NOFS, 0); + if (!ret) + *discarded_bytes += bytes_left; + } + return ret; } int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, @@ -1906,14 +1973,16 @@ int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, for (i = 0; i < bbio->num_stripes; i++, stripe++) { + u64 bytes; if (!stripe->dev->can_discard) continue; ret = btrfs_issue_discard(stripe->dev->bdev, stripe->physical, - stripe->length); + stripe->length, + &bytes); if (!ret) - discarded_bytes += stripe->length; + discarded_bytes += bytes; else if (ret != -EOPNOTSUPP) break; /* Logic errors or -ENOMEM, or -EIO but I don't know how that could happen JDM */ @@ -6061,20 +6130,19 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_block_group_cache *block_group, *tmp; + struct list_head *deleted_bgs; struct extent_io_tree *unpin; u64 start; u64 end; int ret; - if (trans->aborted) - return 0; - if (fs_info->pinned_extents == &fs_info->freed_extents[0]) unpin = &fs_info->freed_extents[1]; else unpin = &fs_info->freed_extents[0]; - while (1) { + while (!trans->aborted) { mutex_lock(&fs_info->unused_bg_unpin_mutex); ret = find_first_extent_bit(unpin, 0, &start, &end, EXTENT_DIRTY, NULL); @@ -6093,6 +6161,34 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, cond_resched(); } + /* + * Transaction is finished. We don't need the lock anymore. We + * do need to clean up the block groups in case of a transaction + * abort. + */ + deleted_bgs = &trans->transaction->deleted_bgs; + list_for_each_entry_safe(block_group, tmp, deleted_bgs, bg_list) { + u64 trimmed = 0; + + ret = -EROFS; + if (!trans->aborted) + ret = btrfs_discard_extent(root, + block_group->key.objectid, + block_group->key.offset, + &trimmed); + + list_del_init(&block_group->bg_list); + btrfs_put_block_group_trimming(block_group); + btrfs_put_block_group(block_group); + + if (ret) { + const char *errstr = btrfs_decode_error(ret); + btrfs_warn(fs_info, + "Discard failed while removing blockgroup: errno=%d %s\n", + ret, errstr); + } + } + return 0; } @@ -9830,6 +9926,11 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, * 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); /* @@ -9904,6 +10005,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) 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, @@ -10003,12 +10105,39 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) spin_unlock(&block_group->lock); spin_unlock(&space_info->lock); + /* DISCARD can flip during remount */ + trimming = btrfs_test_opt(root, 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, root, 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) { + WARN_ON(!list_empty(&block_group->bg_list)); + spin_lock(&trans->transaction->deleted_bgs_lock); + list_move(&block_group->bg_list, + &trans->transaction->deleted_bgs); + spin_unlock(&trans->transaction->deleted_bgs_lock); + btrfs_get_block_group(block_group); + } end_trans: btrfs_end_transaction(trans, root); next: @@ -10062,10 +10191,99 @@ int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end) return unpin_extent_range(root, start, end, false); } +/* + * It used to be that old block groups would be left around forever. + * Iterating over them would be enough to trim unused space. Since we + * now automatically remove them, we also need to iterate over unallocated + * space. + * + * We don't want a transaction for this since the discard may take a + * substantial amount of time. We don't require that a transaction be + * running, but we do need to take a running transaction into account + * to ensure that we're not discarding chunks that were released in + * the current transaction. + * + * Holding the chunks lock will prevent other threads from allocating + * or releasing chunks, but it won't prevent a running transaction + * from committing and releasing the memory that the pending chunks + * list head uses. For that, we need to take a reference to the + * transaction. + */ +static int btrfs_trim_free_extents(struct btrfs_device *device, + u64 minlen, u64 *trimmed) +{ + u64 start = 0, len = 0; + int ret; + + *trimmed = 0; + + /* Not writeable = nothing to do. */ + if (!device->writeable) + return 0; + + /* No free space = nothing to do. */ + if (device->total_bytes <= device->bytes_used) + return 0; + + ret = 0; + + while (1) { + struct btrfs_fs_info *fs_info = device->dev_root->fs_info; + struct btrfs_transaction *trans; + u64 bytes; + + ret = mutex_lock_interruptible(&fs_info->chunk_mutex); + if (ret) + return ret; + + down_read(&fs_info->commit_root_sem); + + spin_lock(&fs_info->trans_lock); + trans = fs_info->running_transaction; + if (trans) + atomic_inc(&trans->use_count); + spin_unlock(&fs_info->trans_lock); + + ret = find_free_dev_extent_start(trans, device, minlen, start, + &start, &len); + if (trans) + btrfs_put_transaction(trans); + + if (ret) { + up_read(&fs_info->commit_root_sem); + mutex_unlock(&fs_info->chunk_mutex); + if (ret == -ENOSPC) + ret = 0; + break; + } + + ret = btrfs_issue_discard(device->bdev, start, len, &bytes); + up_read(&fs_info->commit_root_sem); + mutex_unlock(&fs_info->chunk_mutex); + + if (ret) + break; + + start += len; + *trimmed += bytes; + + if (fatal_signal_pending(current)) { + ret = -ERESTARTSYS; + break; + } + + cond_resched(); + } + + return ret; +} + int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_block_group_cache *cache = NULL; + struct btrfs_device *device; + struct list_head *devices; u64 group_trimmed; u64 start; u64 end; @@ -10120,6 +10338,18 @@ int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range) cache = next_block_group(fs_info->tree_root, cache); } + mutex_lock(&root->fs_info->fs_devices->device_list_mutex); + devices = &root->fs_info->fs_devices->alloc_list; + list_for_each_entry(device, devices, dev_alloc_list) { + ret = btrfs_trim_free_extents(device, range->minlen, + &group_trimmed); + if (ret) + break; + + trimmed += group_trimmed; + } + mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); + range->len = trimmed; return ret; } diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index fb5a6b1..abe3a66 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -3272,35 +3272,23 @@ next: return ret; } -int btrfs_trim_block_group(struct btrfs_block_group_cache *block_group, - u64 *trimmed, u64 start, u64 end, u64 minlen) +void btrfs_get_block_group_trimming(struct btrfs_block_group_cache *cache) { - int ret; + atomic_inc(&cache->trimming); +} - *trimmed = 0; +void btrfs_put_block_group_trimming(struct btrfs_block_group_cache *block_group) +{ + struct extent_map_tree *em_tree; + struct extent_map *em; + bool cleanup; spin_lock(&block_group->lock); - if (block_group->removed) { - spin_unlock(&block_group->lock); - return 0; - } - atomic_inc(&block_group->trimming); + cleanup = (atomic_dec_and_test(&block_group->trimming) && + block_group->removed); spin_unlock(&block_group->lock); - ret = trim_no_bitmap(block_group, trimmed, start, end, minlen); - if (ret) - goto out; - - ret = trim_bitmaps(block_group, trimmed, start, end, minlen); -out: - spin_lock(&block_group->lock); - if (atomic_dec_and_test(&block_group->trimming) && - block_group->removed) { - struct extent_map_tree *em_tree; - struct extent_map *em; - - spin_unlock(&block_group->lock); - + if (cleanup) { lock_chunks(block_group->fs_info->chunk_root); em_tree = &block_group->fs_info->mapping_tree.map_tree; write_lock(&em_tree->lock); @@ -3324,10 +3312,31 @@ out: * this block group have left 1 entry each one. Free them. */ __btrfs_remove_free_space_cache(block_group->free_space_ctl); - } else { + } +} + +int btrfs_trim_block_group(struct btrfs_block_group_cache *block_group, + u64 *trimmed, u64 start, u64 end, u64 minlen) +{ + int ret; + + *trimmed = 0; + + spin_lock(&block_group->lock); + if (block_group->removed) { spin_unlock(&block_group->lock); + return 0; } + btrfs_get_block_group_trimming(block_group); + spin_unlock(&block_group->lock); + + ret = trim_no_bitmap(block_group, trimmed, start, end, minlen); + if (ret) + goto out; + ret = trim_bitmaps(block_group, trimmed, start, end, minlen); +out: + btrfs_put_block_group_trimming(block_group); return ret; } diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index d366dd4..c389c13 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -69,7 +69,7 @@ static struct file_system_type btrfs_fs_type; static int btrfs_remount(struct super_block *sb, int *flags, char *data); -static const char *btrfs_decode_error(int errno) +const char *btrfs_decode_error(int errno) { char *errstr = "unknown"; @@ -1651,6 +1651,17 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data) sb->s_flags |= MS_RDONLY; + /* + * Setting MS_RDONLY will put the cleaner thread to + * sleep at the next loop if it's already active. + * If it's already asleep, we'll leave unused block + * groups on disk until we're mounted read-write again + * unless we clean them up here. + */ + mutex_lock(&root->fs_info->cleaner_mutex); + btrfs_delete_unused_bgs(fs_info); + mutex_unlock(&root->fs_info->cleaner_mutex); + btrfs_dev_replace_suspend_for_unmount(fs_info); btrfs_scrub_cancel(fs_info); btrfs_pause_balance(fs_info); diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 91f44c9..20267d4 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -258,6 +258,8 @@ loop: mutex_init(&cur_trans->cache_write_mutex); cur_trans->num_dirty_bgs = 0; spin_lock_init(&cur_trans->dirty_bgs_lock); + INIT_LIST_HEAD(&cur_trans->deleted_bgs); + spin_lock_init(&cur_trans->deleted_bgs_lock); list_add_tail(&cur_trans->list, &fs_info->trans_list); extent_io_tree_init(&cur_trans->dirty_pages, fs_info->btree_inode->i_mapping); diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index eb09c20..edc2fbc 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -74,6 +74,8 @@ struct btrfs_transaction { */ struct mutex cache_write_mutex; spinlock_t dirty_bgs_lock; + struct list_head deleted_bgs; + spinlock_t deleted_bgs_lock; struct btrfs_delayed_ref_root delayed_refs; int aborted; int dirty_bg_run; diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 88e2fe9..7c84a81 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1116,15 +1116,18 @@ out: return ret; } -static int contains_pending_extent(struct btrfs_trans_handle *trans, +static int contains_pending_extent(struct btrfs_transaction *transaction, struct btrfs_device *device, u64 *start, u64 len) { + struct btrfs_fs_info *fs_info = device->dev_root->fs_info; struct extent_map *em; - struct list_head *search_list = &trans->transaction->pending_chunks; + struct list_head *search_list = &fs_info->pinned_chunks; int ret = 0; u64 physical_start = *start; + if (transaction) + search_list = &transaction->pending_chunks; again: list_for_each_entry(em, search_list, list) { struct map_lookup *map; @@ -1159,8 +1162,8 @@ again: } } } - if (search_list == &trans->transaction->pending_chunks) { - search_list = &trans->root->fs_info->pinned_chunks; + if (search_list != &fs_info->pinned_chunks) { + search_list = &fs_info->pinned_chunks; goto again; } @@ -1169,12 +1172,13 @@ again: /* - * find_free_dev_extent - find free space in the specified device - * @device: the device which we search the free space in - * @num_bytes: the size of the free space that we need - * @start: store the start of the free space. - * @len: the size of the free space. that we find, or the size of the max - * free space if we don't find suitable free space + * find_free_dev_extent_start - find free space in the specified device + * @device: the device which we search the free space in + * @num_bytes: the size of the free space that we need + * @search_start: the position from which to begin the search + * @start: store the start of the free space. + * @len: the size of the free space. that we find, or the size + * of the max free space if we don't find suitable free space * * this uses a pretty simple search, the expectation is that it is * called very infrequently and that a given device has a small number @@ -1188,9 +1192,9 @@ again: * But if we don't find suitable free space, it is used to store the size of * the max free space. */ -int find_free_dev_extent(struct btrfs_trans_handle *trans, - struct btrfs_device *device, u64 num_bytes, - u64 *start, u64 *len) +int find_free_dev_extent_start(struct btrfs_transaction *transaction, + struct btrfs_device *device, u64 num_bytes, + u64 search_start, u64 *start, u64 *len) { struct btrfs_key key; struct btrfs_root *root = device->dev_root; @@ -1200,19 +1204,11 @@ int find_free_dev_extent(struct btrfs_trans_handle *trans, u64 max_hole_start; u64 max_hole_size; u64 extent_end; - u64 search_start; u64 search_end = device->total_bytes; int ret; int slot; struct extent_buffer *l; - /* FIXME use last free of some kind */ - - /* we don't want to overwrite the superblock on the drive, - * so we make sure to start at an offset of at least 1MB - */ - search_start = max(root->fs_info->alloc_start, 1024ull * 1024); - path = btrfs_alloc_path(); if (!path) return -ENOMEM; @@ -1273,7 +1269,7 @@ again: * Have to check before we set max_hole_start, otherwise * we could end up sending back this offset anyway. */ - if (contains_pending_extent(trans, device, + if (contains_pending_extent(transaction, device, &search_start, hole_size)) { if (key.offset >= search_start) { @@ -1322,7 +1318,7 @@ next: if (search_end > search_start) { hole_size = search_end - search_start; - if (contains_pending_extent(trans, device, &search_start, + if (contains_pending_extent(transaction, device, &search_start, hole_size)) { btrfs_release_path(path); goto again; @@ -1348,6 +1344,24 @@ out: return ret; } +int find_free_dev_extent(struct btrfs_trans_handle *trans, + struct btrfs_device *device, u64 num_bytes, + u64 *start, u64 *len) +{ + struct btrfs_root *root = device->dev_root; + u64 search_start; + + /* FIXME use last free of some kind */ + + /* + * we don't want to overwrite the superblock on the drive, + * so we make sure to start at an offset of at least 1MB + */ + search_start = max(root->fs_info->alloc_start, 1024ull * 1024); + return find_free_dev_extent_start(trans->transaction, device, + num_bytes, search_start, start, len); +} + static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 start, u64 *dev_extent_len) @@ -4196,7 +4210,8 @@ again: u64 start = new_size; u64 len = old_size - new_size; - if (contains_pending_extent(trans, device, &start, len)) { + if (contains_pending_extent(trans->transaction, device, + &start, len)) { unlock_chunks(root); checked_pending_chunks = true; failed = 0; diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 95842a9..2ca784a 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -453,6 +453,9 @@ int btrfs_cancel_balance(struct btrfs_fs_info *fs_info); int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info); int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info); int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset); +int find_free_dev_extent_start(struct btrfs_transaction *transaction, + struct btrfs_device *device, u64 num_bytes, + u64 search_start, u64 *start, u64 *max_avail); int find_free_dev_extent(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 num_bytes, u64 *start, u64 *max_avail); |