From 5b21f2ed3f2947b5195b65c9fdbdd9e52904cc03 Mon Sep 17 00:00:00 2001 From: Zheng Yan Date: Fri, 26 Sep 2008 10:05:38 -0400 Subject: Btrfs: extent_map and data=ordered fixes for space balancing * Add an EXTENT_BOUNDARY state bit to keep the writepage code from merging data extents that are in the process of being relocated. This allows us to do accounting for them properly. * The balancing code relocates data extents indepdent of the underlying inode. The extent_map code was modified to properly account for things moving around (invalidating extent_map caches in the inode). * Don't take the drop_mutex in the create_subvol ioctl. It isn't required. * Fix walking of the ordered extent list to avoid races with sys_unlink * Change the lock ordering rules. Transaction start goes outside the drop_mutex. This allows btrfs_commit_transaction to directly drop the relocation trees. Signed-off-by: Chris Mason diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 50aea8c..f9cd409 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -290,7 +290,6 @@ int noinline btrfs_cow_block(struct btrfs_trans_handle *trans, struct extent_buffer **cow_ret, u64 prealloc_dest) { u64 search_start; - u64 header_trans; int ret; if (trans->transaction != root->fs_info->running_transaction) { @@ -304,9 +303,9 @@ int noinline btrfs_cow_block(struct btrfs_trans_handle *trans, WARN_ON(1); } - header_trans = btrfs_header_generation(buf); spin_lock(&root->fs_info->hash_lock); - if (header_trans == trans->transid && + if (btrfs_header_generation(buf) == trans->transid && + btrfs_header_owner(buf) == root->root_key.objectid && !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { *cow_ret = buf; spin_unlock(&root->fs_info->hash_lock); @@ -1300,6 +1299,7 @@ again: /* is a cow on this block not required */ spin_lock(&root->fs_info->hash_lock); if (btrfs_header_generation(b) == trans->transid && + btrfs_header_owner(b) == root->root_key.objectid && !btrfs_header_flag(b, BTRFS_HEADER_FLAG_WRITTEN)) { spin_unlock(&root->fs_info->hash_lock); goto cow_done; @@ -1396,7 +1396,8 @@ cow_done: /* this is only true while dropping a snapshot */ if (level == lowest_level) { - break; + ret = 0; + goto done; } blocknr = btrfs_node_blockptr(b, slot); diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index b9f9f81..3e62a1b 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1486,6 +1486,9 @@ static inline struct dentry *fdentry(struct file *file) /* extent-tree.c */ int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len); +int btrfs_lookup_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 bytenr, + u64 num_bytes, u32 *refs); int btrfs_update_pinned_extents(struct btrfs_root *root, u64 bytenr, u64 num, int pin); int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans, @@ -1812,6 +1815,8 @@ void btrfs_destroy_inode(struct inode *inode); int btrfs_init_cachep(void); void btrfs_destroy_cachep(void); long btrfs_ioctl_trans_end(struct file *file); +struct inode *btrfs_ilookup(struct super_block *s, u64 objectid, + struct btrfs_root *root, int wait); struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid, struct btrfs_root *root); struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, @@ -1824,13 +1829,17 @@ struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, int btrfs_update_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode); +int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode); +int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode); +void btrfs_orphan_cleanup(struct btrfs_root *root); /* ioctl.c */ long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg); /* file.c */ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync); -int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end); +int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, + int skip_pinned); int btrfs_check_file(struct btrfs_root *root, struct inode *inode); extern struct file_operations btrfs_file_operations; int btrfs_drop_extents(struct btrfs_trans_handle *trans, diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index e3a25be..8bd1b40 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -292,7 +292,7 @@ static int merge_state(struct extent_io_tree *tree, struct extent_state *other; struct rb_node *other_node; - if (state->state & EXTENT_IOBITS) + if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) return 0; other_node = rb_prev(&state->rb_node); @@ -1070,7 +1070,8 @@ search_again: while(1) { state = rb_entry(node, struct extent_state, rb_node); - if (found && state->start != cur_start) { + if (found && (state->start != cur_start || + (state->state & EXTENT_BOUNDARY))) { goto out; } if (!(state->state & EXTENT_DELALLOC)) { @@ -1078,7 +1079,7 @@ search_again: *end = state->end; goto out; } - if (!found) { + if (!found && !(state->state & EXTENT_BOUNDARY)) { struct extent_state *prev_state; struct rb_node *prev_node = node; while(1) { @@ -1088,7 +1089,11 @@ search_again: prev_state = rb_entry(prev_node, struct extent_state, rb_node); - if (!(prev_state->state & EXTENT_DELALLOC)) + if ((prev_state->end + 1 != state->start) || + !(prev_state->state & EXTENT_DELALLOC)) + break; + if ((cur_start - prev_state->start) * 2 > + max_bytes) break; state = prev_state; node = prev_node; diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 3cb411a..c9d1908 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -15,6 +15,7 @@ #define EXTENT_BUFFER_FILLED (1 << 8) #define EXTENT_ORDERED (1 << 9) #define EXTENT_ORDERED_METADATA (1 << 10) +#define EXTENT_BOUNDARY (1 << 11) #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK) /* diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 8856570..1b7e51a 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -294,7 +294,7 @@ static int noinline dirty_and_release_pages(struct btrfs_trans_handle *trans, last_pos_in_file, 0, 0, hole_size, 0); btrfs_drop_extent_cache(inode, last_pos_in_file, - last_pos_in_file + hole_size -1); + last_pos_in_file + hole_size - 1, 0); mutex_unlock(&BTRFS_I(inode)->extent_mutex); btrfs_check_file(root, inode); } @@ -337,7 +337,7 @@ static int noinline dirty_and_release_pages(struct btrfs_trans_handle *trans, inline_size -= start_pos; err = insert_inline_extent(trans, root, inode, start_pos, inline_size, pages, 0, num_pages); - btrfs_drop_extent_cache(inode, start_pos, aligned_end - 1); + btrfs_drop_extent_cache(inode, start_pos, aligned_end - 1, 0); BUG_ON(err); mutex_unlock(&BTRFS_I(inode)->extent_mutex); @@ -362,7 +362,8 @@ out_unlock: return err; } -int noinline btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end) +int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, + int skip_pinned) { struct extent_map *em; struct extent_map *split = NULL; @@ -371,6 +372,7 @@ int noinline btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end) u64 len = end - start + 1; int ret; int testend = 1; + unsigned long flags; WARN_ON(end < start); if (end == (u64)-1) { @@ -389,6 +391,23 @@ int noinline btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end) spin_unlock(&em_tree->lock); break; } + flags = em->flags; + if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) { + spin_unlock(&em_tree->lock); + if (em->start <= start && + (!testend || em->start + em->len >= start + len)) { + free_extent_map(em); + break; + } + if (start < em->start) { + len = em->start - start; + } else { + len = start + len - (em->start + em->len); + start = em->start + em->len; + } + free_extent_map(em); + continue; + } clear_bit(EXTENT_FLAG_PINNED, &em->flags); remove_extent_mapping(em_tree, em); @@ -398,7 +417,7 @@ int noinline btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end) split->len = start - em->start; split->block_start = em->block_start; split->bdev = em->bdev; - split->flags = em->flags; + split->flags = flags; ret = add_extent_mapping(em_tree, split); BUG_ON(ret); free_extent_map(split); @@ -412,7 +431,7 @@ int noinline btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end) split->start = start + len; split->len = em->start + em->len - (start + len); split->bdev = em->bdev; - split->flags = em->flags; + split->flags = flags; split->block_start = em->block_start + diff; @@ -541,7 +560,7 @@ int noinline btrfs_drop_extents(struct btrfs_trans_handle *trans, int recow; int ret; - btrfs_drop_extent_cache(inode, start, end - 1); + btrfs_drop_extent_cache(inode, start, end - 1, 0); path = btrfs_alloc_path(); if (!path) diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c index cd6171c..80038c5 100644 --- a/fs/btrfs/inode-map.c +++ b/fs/btrfs/inode-map.c @@ -117,10 +117,14 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans, *objectid = last_ino; goto found; } + } else if (key.objectid > search_start) { + *objectid = search_start; + goto found; } } if (key.objectid >= BTRFS_LAST_FREE_OBJECTID) break; + start_found = 1; last_ino = key.objectid + 1; path->slots[0]++; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 48a3dc0..4516fbf 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -135,7 +135,7 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end) BUG_ON(num_bytes > btrfs_super_total_bytes(&root->fs_info->super_copy)); mutex_lock(&BTRFS_I(inode)->extent_mutex); - btrfs_drop_extent_cache(inode, start, start + num_bytes - 1); + btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); mutex_unlock(&BTRFS_I(inode)->extent_mutex); while(num_bytes > 0) { @@ -163,7 +163,7 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end) break; } btrfs_drop_extent_cache(inode, start, - start + ins.offset - 1); + start + ins.offset - 1, 0); } mutex_unlock(&BTRFS_I(inode)->extent_mutex); @@ -587,7 +587,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) btrfs_drop_extent_cache(inode, ordered_extent->file_offset, ordered_extent->file_offset + - ordered_extent->len - 1); + ordered_extent->len - 1, 0); mutex_unlock(&BTRFS_I(inode)->extent_mutex); ins.objectid = ordered_extent->start; @@ -880,7 +880,7 @@ void btrfs_orphan_cleanup(struct btrfs_root *root) int ret = 0, nr_unlink = 0, nr_truncate = 0; /* don't do orphan cleanup if the fs is readonly. */ - if (root->inode->i_sb->s_flags & MS_RDONLY) + if (root->fs_info->sb->s_flags & MS_RDONLY) return; path = btrfs_alloc_path(); @@ -892,8 +892,6 @@ void btrfs_orphan_cleanup(struct btrfs_root *root) btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY); key.offset = (u64)-1; - trans = btrfs_start_transaction(root, 1); - btrfs_set_trans_block_group(trans, root->inode); while (1) { ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); @@ -933,7 +931,7 @@ void btrfs_orphan_cleanup(struct btrfs_root *root) * crossing root thing. we store the inode number in the * offset of the orphan item. */ - inode = btrfs_iget_locked(root->inode->i_sb, + inode = btrfs_iget_locked(root->fs_info->sb, found_key.offset, root); if (!inode) break; @@ -965,7 +963,9 @@ void btrfs_orphan_cleanup(struct btrfs_root *root) * do a destroy_inode */ if (is_bad_inode(inode)) { + trans = btrfs_start_transaction(root, 1); btrfs_orphan_del(trans, inode); + btrfs_end_transaction(trans, root); iput(inode); continue; } @@ -988,7 +988,6 @@ void btrfs_orphan_cleanup(struct btrfs_root *root) printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate); btrfs_free_path(path); - btrfs_end_transaction(trans, root); } void btrfs_read_locked_inode(struct inode *inode) @@ -1343,8 +1342,7 @@ noinline int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, u64 mask = root->sectorsize - 1; if (root->ref_cows) - btrfs_drop_extent_cache(inode, - new_size & (~mask), (u64)-1); + btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0); path = btrfs_alloc_path(); path->reada = -1; BUG_ON(!path); @@ -1677,7 +1675,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) hole_start, 0, 0, hole_size, 0); btrfs_drop_extent_cache(inode, hole_start, - (u64)-1); + (u64)-1, 0); btrfs_check_file(root, inode); } mutex_unlock(&BTRFS_I(inode)->extent_mutex); @@ -1843,6 +1841,24 @@ static int btrfs_find_actor(struct inode *inode, void *opaque) args->root == BTRFS_I(inode)->root); } +struct inode *btrfs_ilookup(struct super_block *s, u64 objectid, + struct btrfs_root *root, int wait) +{ + struct inode *inode; + struct btrfs_iget_args args; + args.ino = objectid; + args.root = root; + + if (wait) { + inode = ilookup5(s, objectid, btrfs_find_actor, + (void *)&args); + } else { + inode = ilookup5_nowait(s, objectid, btrfs_find_actor, + (void *)&args); + } + return inode; +} + struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid, struct btrfs_root *root) { @@ -3266,7 +3282,7 @@ void btrfs_destroy_inode(struct inode *inode) btrfs_put_ordered_extent(ordered); } } - btrfs_drop_extent_cache(inode, 0, (u64)-1); + btrfs_drop_extent_cache(inode, 0, (u64)-1, 0); kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); } @@ -3412,16 +3428,22 @@ int btrfs_start_delalloc_inodes(struct btrfs_root *root) { struct list_head *head = &root->fs_info->delalloc_inodes; struct btrfs_inode *binode; + struct inode *inode; unsigned long flags; spin_lock_irqsave(&root->fs_info->delalloc_lock, flags); while(!list_empty(head)) { binode = list_entry(head->next, struct btrfs_inode, delalloc_inodes); - atomic_inc(&binode->vfs_inode.i_count); + inode = igrab(&binode->vfs_inode); + if (!inode) + list_del_init(&binode->delalloc_inodes); spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags); - filemap_write_and_wait(binode->vfs_inode.i_mapping); - iput(&binode->vfs_inode); + if (inode) { + filemap_write_and_wait(inode->i_mapping); + iput(inode); + } + cond_resched(); spin_lock_irqsave(&root->fs_info->delalloc_lock, flags); } spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags); diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 4c6e0c15..04de767 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -444,12 +444,10 @@ static noinline int btrfs_ioctl_snap_create(struct btrfs_root *root, goto out; } - mutex_lock(&root->fs_info->drop_mutex); if (root == root->fs_info->tree_root) ret = create_subvol(root, vol_args->name, namelen); else ret = create_snapshot(root, vol_args->name, namelen); - mutex_unlock(&root->fs_info->drop_mutex); out: kfree(vol_args); return ret; diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index da6d43e..951eacf 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -309,7 +309,6 @@ int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only) { struct list_head splice; struct list_head *cur; - struct list_head *tmp; struct btrfs_ordered_extent *ordered; struct inode *inode; @@ -317,37 +316,38 @@ int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only) spin_lock(&root->fs_info->ordered_extent_lock); list_splice_init(&root->fs_info->ordered_extents, &splice); - list_for_each_safe(cur, tmp, &splice) { + while (!list_empty(&splice)) { cur = splice.next; ordered = list_entry(cur, struct btrfs_ordered_extent, root_extent_list); if (nocow_only && !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) { + list_move(&ordered->root_extent_list, + &root->fs_info->ordered_extents); cond_resched_lock(&root->fs_info->ordered_extent_lock); continue; } list_del_init(&ordered->root_extent_list); atomic_inc(&ordered->refs); - inode = ordered->inode; /* - * the inode can't go away until all the pages are gone - * and the pages won't go away while there is still - * an ordered extent and the ordered extent won't go - * away until it is off this list. So, we can safely - * increment i_count here and call iput later + * the inode may be getting freed (in sys_unlink path). */ - atomic_inc(&inode->i_count); + inode = igrab(ordered->inode); + spin_unlock(&root->fs_info->ordered_extent_lock); - btrfs_start_ordered_extent(inode, ordered, 1); - btrfs_put_ordered_extent(ordered); - iput(inode); + if (inode) { + btrfs_start_ordered_extent(inode, ordered, 1); + btrfs_put_ordered_extent(ordered); + iput(inode); + } else { + btrfs_put_ordered_extent(ordered); + } spin_lock(&root->fs_info->ordered_extent_lock); } - list_splice_init(&splice, &root->fs_info->ordered_extents); spin_unlock(&root->fs_info->ordered_extent_lock); return 0; } diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 656baef..8c83cf4 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -109,6 +109,7 @@ noinline int btrfs_record_root_in_trans(struct btrfs_root *root) spin_lock_init(&dirty->root->node_lock); spin_lock_init(&dirty->root->list_lock); mutex_init(&dirty->root->objectid_mutex); + mutex_init(&dirty->root->log_mutex); INIT_LIST_HEAD(&dirty->root->dead_list); dirty->root->node = root->commit_root; dirty->root->commit_root = NULL; @@ -590,13 +591,14 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root, root = dirty->latest_root; atomic_inc(&root->fs_info->throttles); - mutex_lock(&root->fs_info->drop_mutex); while(1) { trans = btrfs_start_transaction(tree_root, 1); + mutex_lock(&root->fs_info->drop_mutex); ret = btrfs_drop_snapshot(trans, dirty->root); if (ret != -EAGAIN) { break; } + mutex_unlock(&root->fs_info->drop_mutex); err = btrfs_update_root(trans, tree_root, @@ -608,10 +610,8 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root, ret = btrfs_end_transaction(trans, tree_root); BUG_ON(ret); - mutex_unlock(&root->fs_info->drop_mutex); btrfs_btree_balance_dirty(tree_root, nr); cond_resched(); - mutex_lock(&root->fs_info->drop_mutex); } BUG_ON(ret); atomic_dec(&root->fs_info->throttles); @@ -689,7 +689,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); key.objectid = objectid; - key.offset = 1; + key.offset = trans->transid; btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); old = btrfs_lock_root_node(root); -- cgit v0.10.2