diff options
Diffstat (limited to 'fs/btrfs/ordered-data.c')
| -rw-r--r-- | fs/btrfs/ordered-data.c | 1371 |
1 files changed, 1371 insertions, 0 deletions
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c new file mode 100644 index 000000000..b32d4eabe --- /dev/null +++ b/fs/btrfs/ordered-data.c @@ -0,0 +1,1371 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2007 Oracle. All rights reserved. + */ + +#include <linux/slab.h> +#include <linux/blkdev.h> +#include <linux/writeback.h> +#include <linux/sched/mm.h> +#include "messages.h" +#include "misc.h" +#include "ctree.h" +#include "transaction.h" +#include "btrfs_inode.h" +#include "extent_io.h" +#include "disk-io.h" +#include "compression.h" +#include "delalloc-space.h" +#include "qgroup.h" +#include "subpage.h" +#include "file.h" +#include "block-group.h" + +static struct kmem_cache *btrfs_ordered_extent_cache; + +static u64 entry_end(struct btrfs_ordered_extent *entry) +{ + if (entry->file_offset + entry->num_bytes < entry->file_offset) + return (u64)-1; + return entry->file_offset + entry->num_bytes; +} + +/* returns NULL if the insertion worked, or it returns the node it did find + * in the tree + */ +static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset, + struct rb_node *node) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *parent = NULL; + struct btrfs_ordered_extent *entry; + + while (*p) { + parent = *p; + entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node); + + if (file_offset < entry->file_offset) + p = &(*p)->rb_left; + else if (file_offset >= entry_end(entry)) + p = &(*p)->rb_right; + else + return parent; + } + + rb_link_node(node, parent, p); + rb_insert_color(node, root); + return NULL; +} + +/* + * look for a given offset in the tree, and if it can't be found return the + * first lesser offset + */ +static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset, + struct rb_node **prev_ret) +{ + struct rb_node *n = root->rb_node; + struct rb_node *prev = NULL; + struct rb_node *test; + struct btrfs_ordered_extent *entry; + struct btrfs_ordered_extent *prev_entry = NULL; + + while (n) { + entry = rb_entry(n, struct btrfs_ordered_extent, rb_node); + prev = n; + prev_entry = entry; + + if (file_offset < entry->file_offset) + n = n->rb_left; + else if (file_offset >= entry_end(entry)) + n = n->rb_right; + else + return n; + } + if (!prev_ret) + return NULL; + + while (prev && file_offset >= entry_end(prev_entry)) { + test = rb_next(prev); + if (!test) + break; + prev_entry = rb_entry(test, struct btrfs_ordered_extent, + rb_node); + if (file_offset < entry_end(prev_entry)) + break; + + prev = test; + } + if (prev) + prev_entry = rb_entry(prev, struct btrfs_ordered_extent, + rb_node); + while (prev && file_offset < entry_end(prev_entry)) { + test = rb_prev(prev); + if (!test) + break; + prev_entry = rb_entry(test, struct btrfs_ordered_extent, + rb_node); + prev = test; + } + *prev_ret = prev; + return NULL; +} + +static int btrfs_range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset, + u64 len) +{ + if (file_offset + len <= entry->file_offset || + entry->file_offset + entry->num_bytes <= file_offset) + return 0; + return 1; +} + +/* + * look find the first ordered struct that has this offset, otherwise + * the first one less than this offset + */ +static inline struct rb_node *ordered_tree_search(struct btrfs_inode *inode, + u64 file_offset) +{ + struct rb_node *prev = NULL; + struct rb_node *ret; + struct btrfs_ordered_extent *entry; + + if (inode->ordered_tree_last) { + entry = rb_entry(inode->ordered_tree_last, struct btrfs_ordered_extent, + rb_node); + if (in_range(file_offset, entry->file_offset, entry->num_bytes)) + return inode->ordered_tree_last; + } + ret = __tree_search(&inode->ordered_tree, file_offset, &prev); + if (!ret) + ret = prev; + if (ret) + inode->ordered_tree_last = ret; + return ret; +} + +static struct btrfs_ordered_extent *alloc_ordered_extent( + struct btrfs_inode *inode, u64 file_offset, u64 num_bytes, + u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes, + u64 offset, unsigned long flags, int compress_type) +{ + struct btrfs_ordered_extent *entry; + int ret; + u64 qgroup_rsv = 0; + const bool is_nocow = (flags & + ((1U << BTRFS_ORDERED_NOCOW) | (1U << BTRFS_ORDERED_PREALLOC))); + + /* Only one type flag can be set. */ + ASSERT(has_single_bit_set(flags & BTRFS_ORDERED_EXCLUSIVE_FLAGS), + "flags=0x%lx", flags); + + /* DIRECT cannot be set with COMPRESSED nor ENCODED. */ + if (test_bit(BTRFS_ORDERED_DIRECT, &flags)) { + ASSERT(!test_bit(BTRFS_ORDERED_COMPRESSED, &flags)); + ASSERT(!test_bit(BTRFS_ORDERED_ENCODED, &flags)); + } + + /* ENCODED must be set with COMPRESSED. */ + if (test_bit(BTRFS_ORDERED_ENCODED, &flags)) + ASSERT(test_bit(BTRFS_ORDERED_COMPRESSED, &flags)); + + /* + * For a NOCOW write we can free the qgroup reserve right now. For a COW + * one we transfer the reserved space from the inode's iotree into the + * ordered extent by calling btrfs_qgroup_release_data() and tracking + * the qgroup reserved amount in the ordered extent, so that later after + * completing the ordered extent, when running the data delayed ref it + * creates, we free the reserved data with btrfs_qgroup_free_refroot(). + */ + if (is_nocow) + ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes, &qgroup_rsv); + else + ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes, &qgroup_rsv); + + if (ret < 0) + return ERR_PTR(ret); + + entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS); + if (!entry) { + entry = ERR_PTR(-ENOMEM); + goto out; + } + + entry->file_offset = file_offset; + entry->num_bytes = num_bytes; + entry->ram_bytes = ram_bytes; + entry->disk_bytenr = disk_bytenr; + entry->disk_num_bytes = disk_num_bytes; + entry->offset = offset; + entry->bytes_left = num_bytes; + if (WARN_ON_ONCE(!igrab(&inode->vfs_inode))) { + kmem_cache_free(btrfs_ordered_extent_cache, entry); + entry = ERR_PTR(-ESTALE); + goto out; + } + entry->inode = inode; + entry->compress_type = compress_type; + entry->truncated_len = (u64)-1; + entry->qgroup_rsv = qgroup_rsv; + entry->flags = flags; + refcount_set(&entry->refs, 1); + init_waitqueue_head(&entry->wait); + INIT_LIST_HEAD(&entry->csum_list); + INIT_LIST_HEAD(&entry->log_list); + INIT_LIST_HEAD(&entry->root_extent_list); + INIT_LIST_HEAD(&entry->work_list); + INIT_LIST_HEAD(&entry->bioc_list); + init_completion(&entry->completion); + + /* + * We don't need the count_max_extents here, we can assume that all of + * that work has been done at higher layers, so this is truly the + * smallest the extent is going to get. + */ + spin_lock(&inode->lock); + btrfs_mod_outstanding_extents(inode, 1); + spin_unlock(&inode->lock); + +out: + if (IS_ERR(entry) && !is_nocow) + btrfs_qgroup_free_refroot(inode->root->fs_info, + btrfs_root_id(inode->root), + qgroup_rsv, BTRFS_QGROUP_RSV_DATA); + + return entry; +} + +static void insert_ordered_extent(struct btrfs_ordered_extent *entry) +{ + struct btrfs_inode *inode = entry->inode; + struct btrfs_root *root = inode->root; + struct btrfs_fs_info *fs_info = root->fs_info; + struct rb_node *node; + + trace_btrfs_ordered_extent_add(inode, entry); + + percpu_counter_add_batch(&fs_info->ordered_bytes, entry->num_bytes, + fs_info->delalloc_batch); + + /* One ref for the tree. */ + refcount_inc(&entry->refs); + + spin_lock(&inode->ordered_tree_lock); + node = tree_insert(&inode->ordered_tree, entry->file_offset, + &entry->rb_node); + if (unlikely(node)) { + struct btrfs_ordered_extent *exist = + rb_entry(node, struct btrfs_ordered_extent, rb_node); + + btrfs_panic(fs_info, -EEXIST, +"overlapping ordered extents, existing oe file_offset %llu num_bytes %llu flags 0x%lx, new oe file_offset %llu num_bytes %llu flags 0x%lx", + exist->file_offset, exist->num_bytes, exist->flags, + entry->file_offset, entry->num_bytes, entry->flags); + } + spin_unlock(&inode->ordered_tree_lock); + + spin_lock(&root->ordered_extent_lock); + list_add_tail(&entry->root_extent_list, + &root->ordered_extents); + root->nr_ordered_extents++; + if (root->nr_ordered_extents == 1) { + spin_lock(&fs_info->ordered_root_lock); + BUG_ON(!list_empty(&root->ordered_root)); + list_add_tail(&root->ordered_root, &fs_info->ordered_roots); + spin_unlock(&fs_info->ordered_root_lock); + } + spin_unlock(&root->ordered_extent_lock); +} + +/* + * Add an ordered extent to the per-inode tree. + * + * @inode: Inode that this extent is for. + * @file_offset: Logical offset in file where the extent starts. + * @num_bytes: Logical length of extent in file. + * @ram_bytes: Full length of unencoded data. + * @disk_bytenr: Offset of extent on disk. + * @disk_num_bytes: Size of extent on disk. + * @offset: Offset into unencoded data where file data starts. + * @flags: Flags specifying type of extent (1U << BTRFS_ORDERED_*). + * @compress_type: Compression algorithm used for data. + * + * Most of these parameters correspond to &struct btrfs_file_extent_item. The + * tree is given a single reference on the ordered extent that was inserted, and + * the returned pointer is given a second reference. + * + * Return: the new ordered extent or error pointer. + */ +struct btrfs_ordered_extent *btrfs_alloc_ordered_extent( + struct btrfs_inode *inode, u64 file_offset, + const struct btrfs_file_extent *file_extent, unsigned long flags) +{ + struct btrfs_ordered_extent *entry; + + ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0, "flags=0x%lx", flags); + + /* + * For regular writes, we just use the members in @file_extent. + * + * For NOCOW, we don't really care about the numbers except @start and + * file_extent->num_bytes, as we won't insert a file extent item at all. + * + * For PREALLOC, we do not use ordered extent members, but + * btrfs_mark_extent_written() handles everything. + * + * So here we always pass 0 as offset for NOCOW/PREALLOC ordered extents, + * or btrfs_split_ordered_extent() cannot handle it correctly. + */ + if (flags & ((1U << BTRFS_ORDERED_NOCOW) | (1U << BTRFS_ORDERED_PREALLOC))) + entry = alloc_ordered_extent(inode, file_offset, + file_extent->num_bytes, + file_extent->num_bytes, + file_extent->disk_bytenr + file_extent->offset, + file_extent->num_bytes, 0, flags, + file_extent->compression); + else + entry = alloc_ordered_extent(inode, file_offset, + file_extent->num_bytes, + file_extent->ram_bytes, + file_extent->disk_bytenr, + file_extent->disk_num_bytes, + file_extent->offset, flags, + file_extent->compression); + if (!IS_ERR(entry)) + insert_ordered_extent(entry); + return entry; +} + +/* + * Add a struct btrfs_ordered_sum into the list of checksums to be inserted + * when an ordered extent is finished. If the list covers more than one + * ordered extent, it is split across multiples. + */ +void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry, + struct btrfs_ordered_sum *sum) +{ + struct btrfs_inode *inode = entry->inode; + + spin_lock(&inode->ordered_tree_lock); + list_add_tail(&sum->list, &entry->csum_list); + spin_unlock(&inode->ordered_tree_lock); +} + +void btrfs_mark_ordered_extent_error(struct btrfs_ordered_extent *ordered) +{ + if (!test_and_set_bit(BTRFS_ORDERED_IOERR, &ordered->flags)) + mapping_set_error(ordered->inode->vfs_inode.i_mapping, -EIO); +} + +void btrfs_mark_ordered_extent_truncated(struct btrfs_ordered_extent *ordered, + u64 truncate_len) +{ + struct btrfs_inode *inode = ordered->inode; + + ASSERT(truncate_len <= ordered->num_bytes); + spin_lock(&inode->ordered_tree_lock); + set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags); + ordered->truncated_len = min(ordered->truncated_len, truncate_len); + spin_unlock(&inode->ordered_tree_lock); +} + +static void finish_ordered_fn(struct btrfs_work *work) +{ + struct btrfs_ordered_extent *ordered_extent; + + ordered_extent = container_of(work, struct btrfs_ordered_extent, work); + btrfs_finish_ordered_io(ordered_extent); +} + +static bool can_finish_ordered_extent(struct btrfs_ordered_extent *ordered, + u64 file_offset, u64 len, bool uptodate) +{ + struct btrfs_inode *inode = ordered->inode; + struct btrfs_fs_info *fs_info = inode->root->fs_info; + + lockdep_assert_held(&inode->ordered_tree_lock); + + /* Now we're fine to update the accounting. */ + if (WARN_ON_ONCE(len > ordered->bytes_left)) { + btrfs_crit(fs_info, +"bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%llu left=%llu", + btrfs_root_id(inode->root), btrfs_ino(inode), + ordered->file_offset, ordered->num_bytes, + len, ordered->bytes_left); + ordered->bytes_left = 0; + } else { + ordered->bytes_left -= len; + } + + if (!uptodate) + btrfs_mark_ordered_extent_error(ordered); + + if (ordered->bytes_left) + return false; + + /* + * All the IO of the ordered extent is finished, we need to queue + * the finish_func to be executed. + */ + set_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags); + cond_wake_up(&ordered->wait); + refcount_inc(&ordered->refs); + trace_btrfs_ordered_extent_mark_finished(inode, ordered); + return true; +} + +static void btrfs_queue_ordered_fn(struct btrfs_ordered_extent *ordered) +{ + struct btrfs_inode *inode = ordered->inode; + struct btrfs_fs_info *fs_info = inode->root->fs_info; + struct btrfs_workqueue *wq = btrfs_is_free_space_inode(inode) ? + fs_info->endio_freespace_worker : fs_info->endio_write_workers; + + btrfs_init_work(&ordered->work, finish_ordered_fn, NULL); + btrfs_queue_work(wq, &ordered->work); +} + +void btrfs_finish_ordered_extent(struct btrfs_ordered_extent *ordered, + u64 file_offset, u64 len, bool uptodate) +{ + struct btrfs_inode *inode = ordered->inode; + bool ret; + + trace_btrfs_finish_ordered_extent(inode, file_offset, len, uptodate); + + spin_lock(&inode->ordered_tree_lock); + ret = can_finish_ordered_extent(ordered, file_offset, len, + uptodate); + spin_unlock(&inode->ordered_tree_lock); + + /* + * If this is a COW write it means we created new extent maps for the + * range and they point to unwritten locations if we got an error either + * before submitting a bio or during IO. + * + * We have marked the ordered extent with BTRFS_ORDERED_IOERR, and we + * are queuing its completion below. During completion, at + * btrfs_finish_one_ordered(), we will drop the extent maps for the + * unwritten extents. + * + * However because completion runs in a work queue we can end up having + * a fast fsync running before that. In the case of direct IO, once we + * unlock the inode the fsync might start, and we queue the completion + * before unlocking the inode. In the case of buffered IO when writeback + * finishes (end_bbio_data_write()) we queue the completion, so if the + * writeback was triggered by a fast fsync, the fsync might start + * logging before ordered extent completion runs in the work queue. + * + * The fast fsync will log file extent items based on the extent maps it + * finds, so if by the time it collects extent maps the ordered extent + * completion didn't happen yet, it will log file extent items that + * point to unwritten extents, resulting in a corruption if a crash + * happens and the log tree is replayed. Note that a fast fsync does not + * wait for completion of ordered extents in order to reduce latency. + * + * Set a flag in the inode so that the next fast fsync will wait for + * ordered extents to complete before starting to log. + */ + if (!uptodate && !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) + set_bit(BTRFS_INODE_COW_WRITE_ERROR, &inode->runtime_flags); + + if (ret) + btrfs_queue_ordered_fn(ordered); +} + +/* + * Mark all ordered extents io inside the specified range finished. + * + * @folio: The involved folio for the operation. + * For uncompressed buffered IO, the folio status also needs to be + * updated to indicate whether the pending ordered io is finished. + * Can be NULL for direct IO and compressed write. + * For these cases, callers are ensured they won't execute the + * endio function twice. + * + * This function is called for endio, thus the range must have ordered + * extent(s) covering it. + */ +void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode, + u64 file_offset, u64 num_bytes, bool uptodate) +{ + struct rb_node *node; + struct btrfs_ordered_extent *entry = NULL; + u64 cur = file_offset; + const u64 end = file_offset + num_bytes; + + trace_btrfs_writepage_end_io_hook(inode, file_offset, end - 1, uptodate); + + spin_lock(&inode->ordered_tree_lock); + while (cur < end) { + u64 entry_end; + u64 this_end; + u64 len; + + node = ordered_tree_search(inode, cur); + /* No ordered extents at all */ + if (!node) + break; + + entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); + entry_end = entry->file_offset + entry->num_bytes; + /* + * |<-- OE --->| | + * cur + * Go to next OE. + */ + if (cur >= entry_end) { + node = rb_next(node); + /* No more ordered extents, exit */ + if (!node) + break; + entry = rb_entry(node, struct btrfs_ordered_extent, + rb_node); + + /* Go to next ordered extent and continue */ + cur = entry->file_offset; + continue; + } + /* + * | |<--- OE --->| + * cur + * Go to the start of OE. + */ + if (cur < entry->file_offset) { + cur = entry->file_offset; + continue; + } + + /* + * Now we are definitely inside one ordered extent. + * + * |<--- OE --->| + * | + * cur + */ + this_end = min(entry_end, end); + len = this_end - cur; + ASSERT(len < U32_MAX); + + if (can_finish_ordered_extent(entry, cur, len, uptodate)) { + spin_unlock(&inode->ordered_tree_lock); + btrfs_queue_ordered_fn(entry); + spin_lock(&inode->ordered_tree_lock); + } + cur += len; + } + spin_unlock(&inode->ordered_tree_lock); +} + +/* + * Finish IO for one ordered extent across a given range. The range can only + * contain one ordered extent. + * + * @cached: The cached ordered extent. If not NULL, we can skip the tree + * search and use the ordered extent directly. + * Will be also used to store the finished ordered extent. + * @file_offset: File offset for the finished IO + * @io_size: Length of the finish IO range + * + * Return true if the ordered extent is finished in the range, and update + * @cached. + * Return false otherwise. + * + * NOTE: The range can NOT cross multiple ordered extents. + * Thus caller should ensure the range doesn't cross ordered extents. + */ +bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode, + struct btrfs_ordered_extent **cached, + u64 file_offset, u64 io_size) +{ + struct rb_node *node; + struct btrfs_ordered_extent *entry = NULL; + bool finished = false; + + spin_lock(&inode->ordered_tree_lock); + if (cached && *cached) { + entry = *cached; + goto have_entry; + } + + node = ordered_tree_search(inode, file_offset); + if (!node) + goto out; + + entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); +have_entry: + if (!in_range(file_offset, entry->file_offset, entry->num_bytes)) + goto out; + + if (io_size > entry->bytes_left) + btrfs_crit(inode->root->fs_info, + "bad ordered accounting left %llu size %llu", + entry->bytes_left, io_size); + + entry->bytes_left -= io_size; + + if (entry->bytes_left == 0) { + /* + * Ensure only one caller can set the flag and finished_ret + * accordingly + */ + finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); + /* test_and_set_bit implies a barrier */ + cond_wake_up_nomb(&entry->wait); + } +out: + if (finished && cached && entry) { + *cached = entry; + refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_dec_test_pending(inode, entry); + } + spin_unlock(&inode->ordered_tree_lock); + return finished; +} + +/* + * used to drop a reference on an ordered extent. This will free + * the extent if the last reference is dropped + */ +void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry) +{ + trace_btrfs_ordered_extent_put(entry->inode, entry); + + if (refcount_dec_and_test(&entry->refs)) { + struct btrfs_ordered_sum *sum; + struct btrfs_ordered_sum *tmp; + + ASSERT(list_empty(&entry->root_extent_list)); + ASSERT(list_empty(&entry->log_list)); + ASSERT(RB_EMPTY_NODE(&entry->rb_node)); + btrfs_add_delayed_iput(entry->inode); + list_for_each_entry_safe(sum, tmp, &entry->csum_list, list) + kvfree(sum); + kmem_cache_free(btrfs_ordered_extent_cache, entry); + } +} + +/* + * remove an ordered extent from the tree. No references are dropped + * and waiters are woken up. + */ +void btrfs_remove_ordered_extent(struct btrfs_ordered_extent *entry) +{ + struct btrfs_inode *btrfs_inode = entry->inode; + struct btrfs_root *root = btrfs_inode->root; + struct btrfs_fs_info *fs_info = root->fs_info; + struct rb_node *node; + bool pending; + bool freespace_inode; + + /* + * If this is a free space inode the thread has not acquired the ordered + * extents lockdep map. + */ + freespace_inode = btrfs_is_free_space_inode(btrfs_inode); + + btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered); + /* This is paired with alloc_ordered_extent(). */ + spin_lock(&btrfs_inode->lock); + btrfs_mod_outstanding_extents(btrfs_inode, -1); + spin_unlock(&btrfs_inode->lock); + if (root != fs_info->tree_root) { + u64 release; + + if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags)) + release = entry->disk_num_bytes; + else + release = entry->num_bytes; + btrfs_delalloc_release_metadata(btrfs_inode, release, + test_bit(BTRFS_ORDERED_IOERR, + &entry->flags)); + } + + percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes, + fs_info->delalloc_batch); + + spin_lock(&btrfs_inode->ordered_tree_lock); + node = &entry->rb_node; + rb_erase(node, &btrfs_inode->ordered_tree); + RB_CLEAR_NODE(node); + if (btrfs_inode->ordered_tree_last == node) + btrfs_inode->ordered_tree_last = NULL; + set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags); + pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags); + spin_unlock(&btrfs_inode->ordered_tree_lock); + + /* + * The current running transaction is waiting on us, we need to let it + * know that we're complete and wake it up. + */ + if (pending) { + struct btrfs_transaction *trans; + + /* + * The checks for trans are just a formality, it should be set, + * but if it isn't we don't want to deref/assert under the spin + * lock, so be nice and check if trans is set, but ASSERT() so + * if it isn't set a developer will notice. + */ + spin_lock(&fs_info->trans_lock); + trans = fs_info->running_transaction; + if (trans) + refcount_inc(&trans->use_count); + spin_unlock(&fs_info->trans_lock); + + ASSERT(trans || BTRFS_FS_ERROR(fs_info)); + if (trans) { + if (atomic_dec_and_test(&trans->pending_ordered)) + wake_up(&trans->pending_wait); + btrfs_put_transaction(trans); + } + } + + btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered); + + spin_lock(&root->ordered_extent_lock); + list_del_init(&entry->root_extent_list); + root->nr_ordered_extents--; + + trace_btrfs_ordered_extent_remove(btrfs_inode, entry); + + if (!root->nr_ordered_extents) { + spin_lock(&fs_info->ordered_root_lock); + BUG_ON(list_empty(&root->ordered_root)); + list_del_init(&root->ordered_root); + spin_unlock(&fs_info->ordered_root_lock); + } + spin_unlock(&root->ordered_extent_lock); + wake_up(&entry->wait); + if (!freespace_inode) + btrfs_lockdep_release(fs_info, btrfs_ordered_extent); +} + +static void btrfs_run_ordered_extent_work(struct btrfs_work *work) +{ + struct btrfs_ordered_extent *ordered; + + ordered = container_of(work, struct btrfs_ordered_extent, flush_work); + btrfs_start_ordered_extent(ordered); + complete(&ordered->completion); +} + +/* + * Wait for all the ordered extents in a root. Use @bg as range or do whole + * range if it's NULL. + */ +u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr, + const struct btrfs_block_group *bg) +{ + struct btrfs_fs_info *fs_info = root->fs_info; + LIST_HEAD(splice); + LIST_HEAD(skipped); + LIST_HEAD(works); + struct btrfs_ordered_extent *ordered, *next; + u64 count = 0; + u64 range_start, range_len; + u64 range_end; + + if (bg) { + range_start = bg->start; + range_len = bg->length; + } else { + range_start = 0; + range_len = U64_MAX; + } + range_end = range_start + range_len; + + mutex_lock(&root->ordered_extent_mutex); + spin_lock(&root->ordered_extent_lock); + list_splice_init(&root->ordered_extents, &splice); + while (!list_empty(&splice) && nr) { + ordered = list_first_entry(&splice, struct btrfs_ordered_extent, + root_extent_list); + + if (range_end <= ordered->disk_bytenr || + ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) { + list_move_tail(&ordered->root_extent_list, &skipped); + cond_resched_lock(&root->ordered_extent_lock); + continue; + } + + list_move_tail(&ordered->root_extent_list, + &root->ordered_extents); + refcount_inc(&ordered->refs); + spin_unlock(&root->ordered_extent_lock); + + btrfs_init_work(&ordered->flush_work, + btrfs_run_ordered_extent_work, NULL); + list_add_tail(&ordered->work_list, &works); + btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work); + + cond_resched(); + if (nr != U64_MAX) + nr--; + count++; + spin_lock(&root->ordered_extent_lock); + } + list_splice_tail(&skipped, &root->ordered_extents); + list_splice_tail(&splice, &root->ordered_extents); + spin_unlock(&root->ordered_extent_lock); + + list_for_each_entry_safe(ordered, next, &works, work_list) { + list_del_init(&ordered->work_list); + wait_for_completion(&ordered->completion); + btrfs_put_ordered_extent(ordered); + cond_resched(); + } + mutex_unlock(&root->ordered_extent_mutex); + + return count; +} + +/* + * Wait for @nr ordered extents that intersect the @bg, or the whole range of + * the filesystem if @bg is NULL. + */ +void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr, + const struct btrfs_block_group *bg) +{ + struct btrfs_root *root; + LIST_HEAD(splice); + u64 done; + + mutex_lock(&fs_info->ordered_operations_mutex); + spin_lock(&fs_info->ordered_root_lock); + list_splice_init(&fs_info->ordered_roots, &splice); + while (!list_empty(&splice) && nr) { + root = list_first_entry(&splice, struct btrfs_root, + ordered_root); + root = btrfs_grab_root(root); + BUG_ON(!root); + list_move_tail(&root->ordered_root, + &fs_info->ordered_roots); + spin_unlock(&fs_info->ordered_root_lock); + + done = btrfs_wait_ordered_extents(root, nr, bg); + btrfs_put_root(root); + + if (nr != U64_MAX) + nr -= done; + + spin_lock(&fs_info->ordered_root_lock); + } + list_splice_tail(&splice, &fs_info->ordered_roots); + spin_unlock(&fs_info->ordered_root_lock); + mutex_unlock(&fs_info->ordered_operations_mutex); +} + +/* + * Start IO and wait for a given ordered extent to finish. + * + * Wait on page writeback for all the pages in the extent but not in + * [@nowriteback_start, @nowriteback_start + @nowriteback_len) and the + * IO completion code to insert metadata into the btree corresponding to the extent. + */ +void btrfs_start_ordered_extent_nowriteback(struct btrfs_ordered_extent *entry, + u64 nowriteback_start, u32 nowriteback_len) +{ + u64 start = entry->file_offset; + u64 end = start + entry->num_bytes - 1; + struct btrfs_inode *inode = entry->inode; + bool freespace_inode; + + trace_btrfs_ordered_extent_start(inode, entry); + + /* + * If this is a free space inode do not take the ordered extents lockdep + * map. + */ + freespace_inode = btrfs_is_free_space_inode(inode); + + /* + * pages in the range can be dirty, clean or writeback. We + * start IO on any dirty ones so the wait doesn't stall waiting + * for the flusher thread to find them + */ + if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags)) { + if (!nowriteback_len) { + filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end); + } else { + if (start < nowriteback_start) + filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, + nowriteback_start - 1); + if (nowriteback_start + nowriteback_len < end) + filemap_fdatawrite_range(inode->vfs_inode.i_mapping, + nowriteback_start + nowriteback_len, + end); + } + } + + if (!freespace_inode) + btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent); + wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE, &entry->flags)); +} + +/* + * Used to wait on ordered extents across a large range of bytes. + */ +int btrfs_wait_ordered_range(struct btrfs_inode *inode, u64 start, u64 len) +{ + int ret = 0; + int ret_wb = 0; + u64 end; + u64 orig_end; + struct btrfs_ordered_extent *ordered; + + if (start + len < start) { + orig_end = OFFSET_MAX; + } else { + orig_end = start + len - 1; + if (orig_end > OFFSET_MAX) + orig_end = OFFSET_MAX; + } + + /* start IO across the range first to instantiate any delalloc + * extents + */ + ret = btrfs_fdatawrite_range(inode, start, orig_end); + if (ret) + return ret; + + /* + * If we have a writeback error don't return immediately. Wait first + * for any ordered extents that haven't completed yet. This is to make + * sure no one can dirty the same page ranges and call writepages() + * before the ordered extents complete - to avoid failures (-EEXIST) + * when adding the new ordered extents to the ordered tree. + */ + ret_wb = filemap_fdatawait_range(inode->vfs_inode.i_mapping, start, orig_end); + + end = orig_end; + while (1) { + ordered = btrfs_lookup_first_ordered_extent(inode, end); + if (!ordered) + break; + if (ordered->file_offset > orig_end) { + btrfs_put_ordered_extent(ordered); + break; + } + if (ordered->file_offset + ordered->num_bytes <= start) { + btrfs_put_ordered_extent(ordered); + break; + } + btrfs_start_ordered_extent(ordered); + end = ordered->file_offset; + /* + * If the ordered extent had an error save the error but don't + * exit without waiting first for all other ordered extents in + * the range to complete. + */ + if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags)) + ret = -EIO; + btrfs_put_ordered_extent(ordered); + if (end == 0 || end == start) + break; + end--; + } + return ret_wb ? ret_wb : ret; +} + +/* + * find an ordered extent corresponding to file_offset. return NULL if + * nothing is found, otherwise take a reference on the extent and return it + */ +struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode, + u64 file_offset) +{ + struct rb_node *node; + struct btrfs_ordered_extent *entry = NULL; + + spin_lock(&inode->ordered_tree_lock); + node = ordered_tree_search(inode, file_offset); + if (!node) + goto out; + + entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); + if (!in_range(file_offset, entry->file_offset, entry->num_bytes)) + entry = NULL; + if (entry) { + refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_lookup(inode, entry); + } +out: + spin_unlock(&inode->ordered_tree_lock); + return entry; +} + +/* Since the DIO code tries to lock a wide area we need to look for any ordered + * extents that exist in the range, rather than just the start of the range. + */ +struct btrfs_ordered_extent *btrfs_lookup_ordered_range( + struct btrfs_inode *inode, u64 file_offset, u64 len) +{ + struct rb_node *node; + struct btrfs_ordered_extent *entry = NULL; + + spin_lock(&inode->ordered_tree_lock); + node = ordered_tree_search(inode, file_offset); + if (!node) { + node = ordered_tree_search(inode, file_offset + len); + if (!node) + goto out; + } + + while (1) { + entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); + if (btrfs_range_overlaps(entry, file_offset, len)) + break; + + if (entry->file_offset >= file_offset + len) { + entry = NULL; + break; + } + entry = NULL; + node = rb_next(node); + if (!node) + break; + } +out: + if (entry) { + refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_lookup_range(inode, entry); + } + spin_unlock(&inode->ordered_tree_lock); + return entry; +} + +/* + * Adds all ordered extents to the given list. The list ends up sorted by the + * file_offset of the ordered extents. + */ +void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode, + struct list_head *list) +{ + struct rb_node *n; + + btrfs_assert_inode_locked(inode); + + spin_lock(&inode->ordered_tree_lock); + for (n = rb_first(&inode->ordered_tree); n; n = rb_next(n)) { + struct btrfs_ordered_extent *ordered; + + ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node); + + if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags)) + continue; + + ASSERT(list_empty(&ordered->log_list)); + list_add_tail(&ordered->log_list, list); + refcount_inc(&ordered->refs); + trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered); + } + spin_unlock(&inode->ordered_tree_lock); +} + +/* + * lookup and return any extent before 'file_offset'. NULL is returned + * if none is found + */ +struct btrfs_ordered_extent * +btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset) +{ + struct rb_node *node; + struct btrfs_ordered_extent *entry = NULL; + + spin_lock(&inode->ordered_tree_lock); + node = ordered_tree_search(inode, file_offset); + if (!node) + goto out; + + entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); + refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_lookup_first(inode, entry); +out: + spin_unlock(&inode->ordered_tree_lock); + return entry; +} + +/* + * Lookup the first ordered extent that overlaps the range + * [@file_offset, @file_offset + @len). + * + * The difference between this and btrfs_lookup_first_ordered_extent() is + * that this one won't return any ordered extent that does not overlap the range. + * And the difference against btrfs_lookup_ordered_extent() is, this function + * ensures the first ordered extent gets returned. + */ +struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range( + struct btrfs_inode *inode, u64 file_offset, u64 len) +{ + struct rb_node *node; + struct rb_node *cur; + struct rb_node *prev; + struct rb_node *next; + struct btrfs_ordered_extent *entry = NULL; + + spin_lock(&inode->ordered_tree_lock); + node = inode->ordered_tree.rb_node; + /* + * Here we don't want to use tree_search() which will use tree->last + * and screw up the search order. + * And __tree_search() can't return the adjacent ordered extents + * either, thus here we do our own search. + */ + while (node) { + entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); + + if (file_offset < entry->file_offset) { + node = node->rb_left; + } else if (file_offset >= entry_end(entry)) { + node = node->rb_right; + } else { + /* + * Direct hit, got an ordered extent that starts at + * @file_offset + */ + goto out; + } + } + if (!entry) { + /* Empty tree */ + goto out; + } + + cur = &entry->rb_node; + /* We got an entry around @file_offset, check adjacent entries */ + if (entry->file_offset < file_offset) { + prev = cur; + next = rb_next(cur); + } else { + prev = rb_prev(cur); + next = cur; + } + if (prev) { + entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node); + if (btrfs_range_overlaps(entry, file_offset, len)) + goto out; + } + if (next) { + entry = rb_entry(next, struct btrfs_ordered_extent, rb_node); + if (btrfs_range_overlaps(entry, file_offset, len)) + goto out; + } + /* No ordered extent in the range */ + entry = NULL; +out: + if (entry) { + refcount_inc(&entry->refs); + trace_btrfs_ordered_extent_lookup_first_range(inode, entry); + } + + spin_unlock(&inode->ordered_tree_lock); + return entry; +} + +/* + * Lock the passed range and ensures all pending ordered extents in it are run + * to completion. + * + * @inode: Inode whose ordered tree is to be searched + * @start: Beginning of range to flush + * @end: Last byte of range to lock + * @cached_state: If passed, will return the extent state responsible for the + * locked range. It's the caller's responsibility to free the + * cached state. + * + * Always return with the given range locked, ensuring after it's called no + * order extent can be pending. + */ +void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start, + u64 end, + struct extent_state **cached_state) +{ + struct btrfs_ordered_extent *ordered; + struct extent_state *cache = NULL; + struct extent_state **cachedp = &cache; + + if (cached_state) + cachedp = cached_state; + + while (1) { + btrfs_lock_extent(&inode->io_tree, start, end, cachedp); + ordered = btrfs_lookup_ordered_range(inode, start, + end - start + 1); + if (!ordered) { + /* + * If no external cached_state has been passed then + * decrement the extra ref taken for cachedp since we + * aren't exposing it outside of this function + */ + if (!cached_state) + refcount_dec(&cache->refs); + break; + } + btrfs_unlock_extent(&inode->io_tree, start, end, cachedp); + btrfs_start_ordered_extent(ordered); + btrfs_put_ordered_extent(ordered); + } +} + +/* + * Lock the passed range and ensure all pending ordered extents in it are run + * to completion in nowait mode. + * + * Return true if btrfs_lock_ordered_range does not return any extents, + * otherwise false. + */ +bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end, + struct extent_state **cached_state) +{ + struct btrfs_ordered_extent *ordered; + + if (!btrfs_try_lock_extent(&inode->io_tree, start, end, cached_state)) + return false; + + ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1); + if (!ordered) + return true; + + btrfs_put_ordered_extent(ordered); + btrfs_unlock_extent(&inode->io_tree, start, end, cached_state); + + return false; +} + +/* Split out a new ordered extent for this first @len bytes of @ordered. */ +struct btrfs_ordered_extent *btrfs_split_ordered_extent( + struct btrfs_ordered_extent *ordered, u64 len) +{ + struct btrfs_inode *inode = ordered->inode; + struct btrfs_root *root = inode->root; + struct btrfs_fs_info *fs_info = root->fs_info; + u64 file_offset = ordered->file_offset; + u64 disk_bytenr = ordered->disk_bytenr; + unsigned long flags = ordered->flags; + struct btrfs_ordered_sum *sum, *tmpsum; + struct btrfs_ordered_extent *new; + struct rb_node *node; + u64 offset = 0; + + trace_btrfs_ordered_extent_split(inode, ordered); + + ASSERT(!(flags & (1U << BTRFS_ORDERED_COMPRESSED)), "flags=0x%lx", flags); + + /* + * The entire bio must be covered by the ordered extent, but we can't + * reduce the original extent to a zero length either. + */ + if (WARN_ON_ONCE(len >= ordered->num_bytes)) + return ERR_PTR(-EINVAL); + /* + * If our ordered extent had an error there's no point in continuing. + * The error may have come from a transaction abort done either by this + * task or some other concurrent task, and the transaction abort path + * iterates over all existing ordered extents and sets the flag + * BTRFS_ORDERED_IOERR on them. + */ + if (unlikely(flags & (1U << BTRFS_ORDERED_IOERR))) { + const int fs_error = BTRFS_FS_ERROR(fs_info); + + return fs_error ? ERR_PTR(fs_error) : ERR_PTR(-EIO); + } + /* We cannot split partially completed ordered extents. */ + if (ordered->bytes_left) { + ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS), "flags=0x%lx", flags); + if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes)) + return ERR_PTR(-EINVAL); + } + /* We cannot split a compressed ordered extent. */ + if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes)) + return ERR_PTR(-EINVAL); + + new = alloc_ordered_extent(inode, file_offset, len, len, disk_bytenr, + len, 0, flags, ordered->compress_type); + if (IS_ERR(new)) + return new; + + /* One ref for the tree. */ + refcount_inc(&new->refs); + + /* + * Take the root's ordered_extent_lock to avoid a race with + * btrfs_wait_ordered_extents() when updating the disk_bytenr and + * disk_num_bytes fields of the ordered extent below. + * + * There's no concern about a previous caller of + * btrfs_wait_ordered_extents() getting the trimmed ordered extent + * before we insert the new one, because even if it gets the ordered + * extent before it's trimmed and the new one inserted, right before it + * uses it or during its use, the ordered extent might have been + * trimmed in the meanwhile, and it missed the new ordered extent. + * There's no way around this and it's harmless for current use cases, + * so we take the root's ordered_extent_lock to fix that race during + * trimming and silence tools like KCSAN. + */ + spin_lock_irq(&root->ordered_extent_lock); + spin_lock(&inode->ordered_tree_lock); + + /* + * We don't have overlapping ordered extents (that would imply double + * allocation of extents) and we checked above that the split length + * does not cross the ordered extent's num_bytes field, so there's + * no need to remove it and re-insert it in the tree. + */ + ordered->file_offset += len; + ordered->disk_bytenr += len; + ordered->num_bytes -= len; + ordered->disk_num_bytes -= len; + ordered->ram_bytes -= len; + + if (test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags)) { + ASSERT(ordered->bytes_left == 0, "ordered->bytes_left=%llu", + ordered->bytes_left); + new->bytes_left = 0; + } else { + ordered->bytes_left -= len; + } + + if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags)) { + if (ordered->truncated_len > len) { + ordered->truncated_len -= len; + } else { + new->truncated_len = ordered->truncated_len; + ordered->truncated_len = 0; + } + } + + list_for_each_entry_safe(sum, tmpsum, &ordered->csum_list, list) { + if (offset == len) + break; + list_move_tail(&sum->list, &new->csum_list); + offset += sum->len; + } + + node = tree_insert(&inode->ordered_tree, new->file_offset, &new->rb_node); + if (unlikely(node)) + btrfs_panic(fs_info, -EEXIST, + "inconsistency in ordered tree at offset %llu after split", + new->file_offset); + spin_unlock(&inode->ordered_tree_lock); + + list_add_tail(&new->root_extent_list, &root->ordered_extents); + root->nr_ordered_extents++; + spin_unlock_irq(&root->ordered_extent_lock); + return new; +} + +int __init ordered_data_init(void) +{ + btrfs_ordered_extent_cache = KMEM_CACHE(btrfs_ordered_extent, 0); + if (!btrfs_ordered_extent_cache) + return -ENOMEM; + + return 0; +} + +void __cold ordered_data_exit(void) +{ + kmem_cache_destroy(btrfs_ordered_extent_cache); +} |