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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /fs/btrfs/delayed-inode.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/btrfs/delayed-inode.c')
-rw-r--r--fs/btrfs/delayed-inode.c2198
1 files changed, 2198 insertions, 0 deletions
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
new file mode 100644
index 000000000..c6426080c
--- /dev/null
+++ b/fs/btrfs/delayed-inode.c
@@ -0,0 +1,2198 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2011 Fujitsu. All rights reserved.
+ * Written by Miao Xie <miaox@cn.fujitsu.com>
+ */
+
+#include <linux/slab.h>
+#include <linux/iversion.h>
+#include "misc.h"
+#include "delayed-inode.h"
+#include "disk-io.h"
+#include "transaction.h"
+#include "ctree.h"
+#include "qgroup.h"
+#include "locking.h"
+#include "inode-item.h"
+
+#define BTRFS_DELAYED_WRITEBACK 512
+#define BTRFS_DELAYED_BACKGROUND 128
+#define BTRFS_DELAYED_BATCH 16
+
+static struct kmem_cache *delayed_node_cache;
+
+int __init btrfs_delayed_inode_init(void)
+{
+ delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
+ sizeof(struct btrfs_delayed_node),
+ 0,
+ SLAB_MEM_SPREAD,
+ NULL);
+ if (!delayed_node_cache)
+ return -ENOMEM;
+ return 0;
+}
+
+void __cold btrfs_delayed_inode_exit(void)
+{
+ kmem_cache_destroy(delayed_node_cache);
+}
+
+static inline void btrfs_init_delayed_node(
+ struct btrfs_delayed_node *delayed_node,
+ struct btrfs_root *root, u64 inode_id)
+{
+ delayed_node->root = root;
+ delayed_node->inode_id = inode_id;
+ refcount_set(&delayed_node->refs, 0);
+ delayed_node->ins_root = RB_ROOT_CACHED;
+ delayed_node->del_root = RB_ROOT_CACHED;
+ mutex_init(&delayed_node->mutex);
+ INIT_LIST_HEAD(&delayed_node->n_list);
+ INIT_LIST_HEAD(&delayed_node->p_list);
+}
+
+static struct btrfs_delayed_node *btrfs_get_delayed_node(
+ struct btrfs_inode *btrfs_inode)
+{
+ struct btrfs_root *root = btrfs_inode->root;
+ u64 ino = btrfs_ino(btrfs_inode);
+ struct btrfs_delayed_node *node;
+
+ node = READ_ONCE(btrfs_inode->delayed_node);
+ if (node) {
+ refcount_inc(&node->refs);
+ return node;
+ }
+
+ spin_lock(&root->inode_lock);
+ node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
+
+ if (node) {
+ if (btrfs_inode->delayed_node) {
+ refcount_inc(&node->refs); /* can be accessed */
+ BUG_ON(btrfs_inode->delayed_node != node);
+ spin_unlock(&root->inode_lock);
+ return node;
+ }
+
+ /*
+ * It's possible that we're racing into the middle of removing
+ * this node from the radix tree. In this case, the refcount
+ * was zero and it should never go back to one. Just return
+ * NULL like it was never in the radix at all; our release
+ * function is in the process of removing it.
+ *
+ * Some implementations of refcount_inc refuse to bump the
+ * refcount once it has hit zero. If we don't do this dance
+ * here, refcount_inc() may decide to just WARN_ONCE() instead
+ * of actually bumping the refcount.
+ *
+ * If this node is properly in the radix, we want to bump the
+ * refcount twice, once for the inode and once for this get
+ * operation.
+ */
+ if (refcount_inc_not_zero(&node->refs)) {
+ refcount_inc(&node->refs);
+ btrfs_inode->delayed_node = node;
+ } else {
+ node = NULL;
+ }
+
+ spin_unlock(&root->inode_lock);
+ return node;
+ }
+ spin_unlock(&root->inode_lock);
+
+ return NULL;
+}
+
+/* Will return either the node or PTR_ERR(-ENOMEM) */
+static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
+ struct btrfs_inode *btrfs_inode)
+{
+ struct btrfs_delayed_node *node;
+ struct btrfs_root *root = btrfs_inode->root;
+ u64 ino = btrfs_ino(btrfs_inode);
+ int ret;
+
+again:
+ node = btrfs_get_delayed_node(btrfs_inode);
+ if (node)
+ return node;
+
+ node = kmem_cache_zalloc(delayed_node_cache, GFP_NOFS);
+ if (!node)
+ return ERR_PTR(-ENOMEM);
+ btrfs_init_delayed_node(node, root, ino);
+
+ /* cached in the btrfs inode and can be accessed */
+ refcount_set(&node->refs, 2);
+
+ ret = radix_tree_preload(GFP_NOFS);
+ if (ret) {
+ kmem_cache_free(delayed_node_cache, node);
+ return ERR_PTR(ret);
+ }
+
+ spin_lock(&root->inode_lock);
+ ret = radix_tree_insert(&root->delayed_nodes_tree, ino, node);
+ if (ret == -EEXIST) {
+ spin_unlock(&root->inode_lock);
+ kmem_cache_free(delayed_node_cache, node);
+ radix_tree_preload_end();
+ goto again;
+ }
+ btrfs_inode->delayed_node = node;
+ spin_unlock(&root->inode_lock);
+ radix_tree_preload_end();
+
+ return node;
+}
+
+/*
+ * Call it when holding delayed_node->mutex
+ *
+ * If mod = 1, add this node into the prepared list.
+ */
+static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
+ struct btrfs_delayed_node *node,
+ int mod)
+{
+ spin_lock(&root->lock);
+ if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
+ if (!list_empty(&node->p_list))
+ list_move_tail(&node->p_list, &root->prepare_list);
+ else if (mod)
+ list_add_tail(&node->p_list, &root->prepare_list);
+ } else {
+ list_add_tail(&node->n_list, &root->node_list);
+ list_add_tail(&node->p_list, &root->prepare_list);
+ refcount_inc(&node->refs); /* inserted into list */
+ root->nodes++;
+ set_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
+ }
+ spin_unlock(&root->lock);
+}
+
+/* Call it when holding delayed_node->mutex */
+static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
+ struct btrfs_delayed_node *node)
+{
+ spin_lock(&root->lock);
+ if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
+ root->nodes--;
+ refcount_dec(&node->refs); /* not in the list */
+ list_del_init(&node->n_list);
+ if (!list_empty(&node->p_list))
+ list_del_init(&node->p_list);
+ clear_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
+ }
+ spin_unlock(&root->lock);
+}
+
+static struct btrfs_delayed_node *btrfs_first_delayed_node(
+ struct btrfs_delayed_root *delayed_root)
+{
+ struct list_head *p;
+ struct btrfs_delayed_node *node = NULL;
+
+ spin_lock(&delayed_root->lock);
+ if (list_empty(&delayed_root->node_list))
+ goto out;
+
+ p = delayed_root->node_list.next;
+ node = list_entry(p, struct btrfs_delayed_node, n_list);
+ refcount_inc(&node->refs);
+out:
+ spin_unlock(&delayed_root->lock);
+
+ return node;
+}
+
+static struct btrfs_delayed_node *btrfs_next_delayed_node(
+ struct btrfs_delayed_node *node)
+{
+ struct btrfs_delayed_root *delayed_root;
+ struct list_head *p;
+ struct btrfs_delayed_node *next = NULL;
+
+ delayed_root = node->root->fs_info->delayed_root;
+ spin_lock(&delayed_root->lock);
+ if (!test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
+ /* not in the list */
+ if (list_empty(&delayed_root->node_list))
+ goto out;
+ p = delayed_root->node_list.next;
+ } else if (list_is_last(&node->n_list, &delayed_root->node_list))
+ goto out;
+ else
+ p = node->n_list.next;
+
+ next = list_entry(p, struct btrfs_delayed_node, n_list);
+ refcount_inc(&next->refs);
+out:
+ spin_unlock(&delayed_root->lock);
+
+ return next;
+}
+
+static void __btrfs_release_delayed_node(
+ struct btrfs_delayed_node *delayed_node,
+ int mod)
+{
+ struct btrfs_delayed_root *delayed_root;
+
+ if (!delayed_node)
+ return;
+
+ delayed_root = delayed_node->root->fs_info->delayed_root;
+
+ mutex_lock(&delayed_node->mutex);
+ if (delayed_node->count)
+ btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
+ else
+ btrfs_dequeue_delayed_node(delayed_root, delayed_node);
+ mutex_unlock(&delayed_node->mutex);
+
+ if (refcount_dec_and_test(&delayed_node->refs)) {
+ struct btrfs_root *root = delayed_node->root;
+
+ spin_lock(&root->inode_lock);
+ /*
+ * Once our refcount goes to zero, nobody is allowed to bump it
+ * back up. We can delete it now.
+ */
+ ASSERT(refcount_read(&delayed_node->refs) == 0);
+ radix_tree_delete(&root->delayed_nodes_tree,
+ delayed_node->inode_id);
+ spin_unlock(&root->inode_lock);
+ kmem_cache_free(delayed_node_cache, delayed_node);
+ }
+}
+
+static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
+{
+ __btrfs_release_delayed_node(node, 0);
+}
+
+static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
+ struct btrfs_delayed_root *delayed_root)
+{
+ struct list_head *p;
+ struct btrfs_delayed_node *node = NULL;
+
+ spin_lock(&delayed_root->lock);
+ if (list_empty(&delayed_root->prepare_list))
+ goto out;
+
+ p = delayed_root->prepare_list.next;
+ list_del_init(p);
+ node = list_entry(p, struct btrfs_delayed_node, p_list);
+ refcount_inc(&node->refs);
+out:
+ spin_unlock(&delayed_root->lock);
+
+ return node;
+}
+
+static inline void btrfs_release_prepared_delayed_node(
+ struct btrfs_delayed_node *node)
+{
+ __btrfs_release_delayed_node(node, 1);
+}
+
+static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u16 data_len,
+ struct btrfs_delayed_node *node,
+ enum btrfs_delayed_item_type type)
+{
+ struct btrfs_delayed_item *item;
+
+ item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
+ if (item) {
+ item->data_len = data_len;
+ item->type = type;
+ item->bytes_reserved = 0;
+ item->delayed_node = node;
+ RB_CLEAR_NODE(&item->rb_node);
+ INIT_LIST_HEAD(&item->log_list);
+ item->logged = false;
+ refcount_set(&item->refs, 1);
+ }
+ return item;
+}
+
+/*
+ * __btrfs_lookup_delayed_item - look up the delayed item by key
+ * @delayed_node: pointer to the delayed node
+ * @index: the dir index value to lookup (offset of a dir index key)
+ *
+ * Note: if we don't find the right item, we will return the prev item and
+ * the next item.
+ */
+static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
+ struct rb_root *root,
+ u64 index)
+{
+ struct rb_node *node = root->rb_node;
+ struct btrfs_delayed_item *delayed_item = NULL;
+
+ while (node) {
+ delayed_item = rb_entry(node, struct btrfs_delayed_item,
+ rb_node);
+ if (delayed_item->index < index)
+ node = node->rb_right;
+ else if (delayed_item->index > index)
+ node = node->rb_left;
+ else
+ return delayed_item;
+ }
+
+ return NULL;
+}
+
+static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
+ struct btrfs_delayed_item *ins)
+{
+ struct rb_node **p, *node;
+ struct rb_node *parent_node = NULL;
+ struct rb_root_cached *root;
+ struct btrfs_delayed_item *item;
+ bool leftmost = true;
+
+ if (ins->type == BTRFS_DELAYED_INSERTION_ITEM)
+ root = &delayed_node->ins_root;
+ else
+ root = &delayed_node->del_root;
+
+ p = &root->rb_root.rb_node;
+ node = &ins->rb_node;
+
+ while (*p) {
+ parent_node = *p;
+ item = rb_entry(parent_node, struct btrfs_delayed_item,
+ rb_node);
+
+ if (item->index < ins->index) {
+ p = &(*p)->rb_right;
+ leftmost = false;
+ } else if (item->index > ins->index) {
+ p = &(*p)->rb_left;
+ } else {
+ return -EEXIST;
+ }
+ }
+
+ rb_link_node(node, parent_node, p);
+ rb_insert_color_cached(node, root, leftmost);
+
+ if (ins->type == BTRFS_DELAYED_INSERTION_ITEM &&
+ ins->index >= delayed_node->index_cnt)
+ delayed_node->index_cnt = ins->index + 1;
+
+ delayed_node->count++;
+ atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
+ return 0;
+}
+
+static void finish_one_item(struct btrfs_delayed_root *delayed_root)
+{
+ int seq = atomic_inc_return(&delayed_root->items_seq);
+
+ /* atomic_dec_return implies a barrier */
+ if ((atomic_dec_return(&delayed_root->items) <
+ BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0))
+ cond_wake_up_nomb(&delayed_root->wait);
+}
+
+static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
+{
+ struct btrfs_delayed_node *delayed_node = delayed_item->delayed_node;
+ struct rb_root_cached *root;
+ struct btrfs_delayed_root *delayed_root;
+
+ /* Not inserted, ignore it. */
+ if (RB_EMPTY_NODE(&delayed_item->rb_node))
+ return;
+
+ /* If it's in a rbtree, then we need to have delayed node locked. */
+ lockdep_assert_held(&delayed_node->mutex);
+
+ delayed_root = delayed_node->root->fs_info->delayed_root;
+
+ BUG_ON(!delayed_root);
+
+ if (delayed_item->type == BTRFS_DELAYED_INSERTION_ITEM)
+ root = &delayed_node->ins_root;
+ else
+ root = &delayed_node->del_root;
+
+ rb_erase_cached(&delayed_item->rb_node, root);
+ RB_CLEAR_NODE(&delayed_item->rb_node);
+ delayed_node->count--;
+
+ finish_one_item(delayed_root);
+}
+
+static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
+{
+ if (item) {
+ __btrfs_remove_delayed_item(item);
+ if (refcount_dec_and_test(&item->refs))
+ kfree(item);
+ }
+}
+
+static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
+ struct btrfs_delayed_node *delayed_node)
+{
+ struct rb_node *p;
+ struct btrfs_delayed_item *item = NULL;
+
+ p = rb_first_cached(&delayed_node->ins_root);
+ if (p)
+ item = rb_entry(p, struct btrfs_delayed_item, rb_node);
+
+ return item;
+}
+
+static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
+ struct btrfs_delayed_node *delayed_node)
+{
+ struct rb_node *p;
+ struct btrfs_delayed_item *item = NULL;
+
+ p = rb_first_cached(&delayed_node->del_root);
+ if (p)
+ item = rb_entry(p, struct btrfs_delayed_item, rb_node);
+
+ return item;
+}
+
+static struct btrfs_delayed_item *__btrfs_next_delayed_item(
+ struct btrfs_delayed_item *item)
+{
+ struct rb_node *p;
+ struct btrfs_delayed_item *next = NULL;
+
+ p = rb_next(&item->rb_node);
+ if (p)
+ next = rb_entry(p, struct btrfs_delayed_item, rb_node);
+
+ return next;
+}
+
+static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
+ struct btrfs_delayed_item *item)
+{
+ struct btrfs_block_rsv *src_rsv;
+ struct btrfs_block_rsv *dst_rsv;
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ u64 num_bytes;
+ int ret;
+
+ if (!trans->bytes_reserved)
+ return 0;
+
+ src_rsv = trans->block_rsv;
+ dst_rsv = &fs_info->delayed_block_rsv;
+
+ num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
+
+ /*
+ * Here we migrate space rsv from transaction rsv, since have already
+ * reserved space when starting a transaction. So no need to reserve
+ * qgroup space here.
+ */
+ ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, true);
+ if (!ret) {
+ trace_btrfs_space_reservation(fs_info, "delayed_item",
+ item->delayed_node->inode_id,
+ num_bytes, 1);
+ /*
+ * For insertions we track reserved metadata space by accounting
+ * for the number of leaves that will be used, based on the delayed
+ * node's index_items_size field.
+ */
+ if (item->type == BTRFS_DELAYED_DELETION_ITEM)
+ item->bytes_reserved = num_bytes;
+ }
+
+ return ret;
+}
+
+static void btrfs_delayed_item_release_metadata(struct btrfs_root *root,
+ struct btrfs_delayed_item *item)
+{
+ struct btrfs_block_rsv *rsv;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+
+ if (!item->bytes_reserved)
+ return;
+
+ rsv = &fs_info->delayed_block_rsv;
+ /*
+ * Check btrfs_delayed_item_reserve_metadata() to see why we don't need
+ * to release/reserve qgroup space.
+ */
+ trace_btrfs_space_reservation(fs_info, "delayed_item",
+ item->delayed_node->inode_id,
+ item->bytes_reserved, 0);
+ btrfs_block_rsv_release(fs_info, rsv, item->bytes_reserved, NULL);
+}
+
+static void btrfs_delayed_item_release_leaves(struct btrfs_delayed_node *node,
+ unsigned int num_leaves)
+{
+ struct btrfs_fs_info *fs_info = node->root->fs_info;
+ const u64 bytes = btrfs_calc_insert_metadata_size(fs_info, num_leaves);
+
+ /* There are no space reservations during log replay, bail out. */
+ if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
+ return;
+
+ trace_btrfs_space_reservation(fs_info, "delayed_item", node->inode_id,
+ bytes, 0);
+ btrfs_block_rsv_release(fs_info, &fs_info->delayed_block_rsv, bytes, NULL);
+}
+
+static int btrfs_delayed_inode_reserve_metadata(
+ struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_delayed_node *node)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_block_rsv *src_rsv;
+ struct btrfs_block_rsv *dst_rsv;
+ u64 num_bytes;
+ int ret;
+
+ src_rsv = trans->block_rsv;
+ dst_rsv = &fs_info->delayed_block_rsv;
+
+ num_bytes = btrfs_calc_metadata_size(fs_info, 1);
+
+ /*
+ * btrfs_dirty_inode will update the inode under btrfs_join_transaction
+ * which doesn't reserve space for speed. This is a problem since we
+ * still need to reserve space for this update, so try to reserve the
+ * space.
+ *
+ * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
+ * we always reserve enough to update the inode item.
+ */
+ if (!src_rsv || (!trans->bytes_reserved &&
+ src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
+ ret = btrfs_qgroup_reserve_meta(root, num_bytes,
+ BTRFS_QGROUP_RSV_META_PREALLOC, true);
+ if (ret < 0)
+ return ret;
+ ret = btrfs_block_rsv_add(fs_info, dst_rsv, num_bytes,
+ BTRFS_RESERVE_NO_FLUSH);
+ /* NO_FLUSH could only fail with -ENOSPC */
+ ASSERT(ret == 0 || ret == -ENOSPC);
+ if (ret)
+ btrfs_qgroup_free_meta_prealloc(root, num_bytes);
+ } else {
+ ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, true);
+ }
+
+ if (!ret) {
+ trace_btrfs_space_reservation(fs_info, "delayed_inode",
+ node->inode_id, num_bytes, 1);
+ node->bytes_reserved = num_bytes;
+ }
+
+ return ret;
+}
+
+static void btrfs_delayed_inode_release_metadata(struct btrfs_fs_info *fs_info,
+ struct btrfs_delayed_node *node,
+ bool qgroup_free)
+{
+ struct btrfs_block_rsv *rsv;
+
+ if (!node->bytes_reserved)
+ return;
+
+ rsv = &fs_info->delayed_block_rsv;
+ trace_btrfs_space_reservation(fs_info, "delayed_inode",
+ node->inode_id, node->bytes_reserved, 0);
+ btrfs_block_rsv_release(fs_info, rsv, node->bytes_reserved, NULL);
+ if (qgroup_free)
+ btrfs_qgroup_free_meta_prealloc(node->root,
+ node->bytes_reserved);
+ else
+ btrfs_qgroup_convert_reserved_meta(node->root,
+ node->bytes_reserved);
+ node->bytes_reserved = 0;
+}
+
+/*
+ * Insert a single delayed item or a batch of delayed items, as many as possible
+ * that fit in a leaf. The delayed items (dir index keys) are sorted by their key
+ * in the rbtree, and if there's a gap between two consecutive dir index items,
+ * then it means at some point we had delayed dir indexes to add but they got
+ * removed (by btrfs_delete_delayed_dir_index()) before we attempted to flush them
+ * into the subvolume tree. Dir index keys also have their offsets coming from a
+ * monotonically increasing counter, so we can't get new keys with an offset that
+ * fits within a gap between delayed dir index items.
+ */
+static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_delayed_item *first_item)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_delayed_node *node = first_item->delayed_node;
+ LIST_HEAD(item_list);
+ struct btrfs_delayed_item *curr;
+ struct btrfs_delayed_item *next;
+ const int max_size = BTRFS_LEAF_DATA_SIZE(fs_info);
+ struct btrfs_item_batch batch;
+ struct btrfs_key first_key;
+ const u32 first_data_size = first_item->data_len;
+ int total_size;
+ char *ins_data = NULL;
+ int ret;
+ bool continuous_keys_only = false;
+
+ lockdep_assert_held(&node->mutex);
+
+ /*
+ * During normal operation the delayed index offset is continuously
+ * increasing, so we can batch insert all items as there will not be any
+ * overlapping keys in the tree.
+ *
+ * The exception to this is log replay, where we may have interleaved
+ * offsets in the tree, so our batch needs to be continuous keys only in
+ * order to ensure we do not end up with out of order items in our leaf.
+ */
+ if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
+ continuous_keys_only = true;
+
+ /*
+ * For delayed items to insert, we track reserved metadata bytes based
+ * on the number of leaves that we will use.
+ * See btrfs_insert_delayed_dir_index() and
+ * btrfs_delayed_item_reserve_metadata()).
+ */
+ ASSERT(first_item->bytes_reserved == 0);
+
+ list_add_tail(&first_item->tree_list, &item_list);
+ batch.total_data_size = first_data_size;
+ batch.nr = 1;
+ total_size = first_data_size + sizeof(struct btrfs_item);
+ curr = first_item;
+
+ while (true) {
+ int next_size;
+
+ next = __btrfs_next_delayed_item(curr);
+ if (!next)
+ break;
+
+ /*
+ * We cannot allow gaps in the key space if we're doing log
+ * replay.
+ */
+ if (continuous_keys_only && (next->index != curr->index + 1))
+ break;
+
+ ASSERT(next->bytes_reserved == 0);
+
+ next_size = next->data_len + sizeof(struct btrfs_item);
+ if (total_size + next_size > max_size)
+ break;
+
+ list_add_tail(&next->tree_list, &item_list);
+ batch.nr++;
+ total_size += next_size;
+ batch.total_data_size += next->data_len;
+ curr = next;
+ }
+
+ if (batch.nr == 1) {
+ first_key.objectid = node->inode_id;
+ first_key.type = BTRFS_DIR_INDEX_KEY;
+ first_key.offset = first_item->index;
+ batch.keys = &first_key;
+ batch.data_sizes = &first_data_size;
+ } else {
+ struct btrfs_key *ins_keys;
+ u32 *ins_sizes;
+ int i = 0;
+
+ ins_data = kmalloc(batch.nr * sizeof(u32) +
+ batch.nr * sizeof(struct btrfs_key), GFP_NOFS);
+ if (!ins_data) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ins_sizes = (u32 *)ins_data;
+ ins_keys = (struct btrfs_key *)(ins_data + batch.nr * sizeof(u32));
+ batch.keys = ins_keys;
+ batch.data_sizes = ins_sizes;
+ list_for_each_entry(curr, &item_list, tree_list) {
+ ins_keys[i].objectid = node->inode_id;
+ ins_keys[i].type = BTRFS_DIR_INDEX_KEY;
+ ins_keys[i].offset = curr->index;
+ ins_sizes[i] = curr->data_len;
+ i++;
+ }
+ }
+
+ ret = btrfs_insert_empty_items(trans, root, path, &batch);
+ if (ret)
+ goto out;
+
+ list_for_each_entry(curr, &item_list, tree_list) {
+ char *data_ptr;
+
+ data_ptr = btrfs_item_ptr(path->nodes[0], path->slots[0], char);
+ write_extent_buffer(path->nodes[0], &curr->data,
+ (unsigned long)data_ptr, curr->data_len);
+ path->slots[0]++;
+ }
+
+ /*
+ * Now release our path before releasing the delayed items and their
+ * metadata reservations, so that we don't block other tasks for more
+ * time than needed.
+ */
+ btrfs_release_path(path);
+
+ ASSERT(node->index_item_leaves > 0);
+
+ /*
+ * For normal operations we will batch an entire leaf's worth of delayed
+ * items, so if there are more items to process we can decrement
+ * index_item_leaves by 1 as we inserted 1 leaf's worth of items.
+ *
+ * However for log replay we may not have inserted an entire leaf's
+ * worth of items, we may have not had continuous items, so decrementing
+ * here would mess up the index_item_leaves accounting. For this case
+ * only clean up the accounting when there are no items left.
+ */
+ if (next && !continuous_keys_only) {
+ /*
+ * We inserted one batch of items into a leaf a there are more
+ * items to flush in a future batch, now release one unit of
+ * metadata space from the delayed block reserve, corresponding
+ * the leaf we just flushed to.
+ */
+ btrfs_delayed_item_release_leaves(node, 1);
+ node->index_item_leaves--;
+ } else if (!next) {
+ /*
+ * There are no more items to insert. We can have a number of
+ * reserved leaves > 1 here - this happens when many dir index
+ * items are added and then removed before they are flushed (file
+ * names with a very short life, never span a transaction). So
+ * release all remaining leaves.
+ */
+ btrfs_delayed_item_release_leaves(node, node->index_item_leaves);
+ node->index_item_leaves = 0;
+ }
+
+ list_for_each_entry_safe(curr, next, &item_list, tree_list) {
+ list_del(&curr->tree_list);
+ btrfs_release_delayed_item(curr);
+ }
+out:
+ kfree(ins_data);
+ return ret;
+}
+
+static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
+ struct btrfs_path *path,
+ struct btrfs_root *root,
+ struct btrfs_delayed_node *node)
+{
+ int ret = 0;
+
+ while (ret == 0) {
+ struct btrfs_delayed_item *curr;
+
+ mutex_lock(&node->mutex);
+ curr = __btrfs_first_delayed_insertion_item(node);
+ if (!curr) {
+ mutex_unlock(&node->mutex);
+ break;
+ }
+ ret = btrfs_insert_delayed_item(trans, root, path, curr);
+ mutex_unlock(&node->mutex);
+ }
+
+ return ret;
+}
+
+static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_delayed_item *item)
+{
+ const u64 ino = item->delayed_node->inode_id;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_delayed_item *curr, *next;
+ struct extent_buffer *leaf = path->nodes[0];
+ LIST_HEAD(batch_list);
+ int nitems, slot, last_slot;
+ int ret;
+ u64 total_reserved_size = item->bytes_reserved;
+
+ ASSERT(leaf != NULL);
+
+ slot = path->slots[0];
+ last_slot = btrfs_header_nritems(leaf) - 1;
+ /*
+ * Our caller always gives us a path pointing to an existing item, so
+ * this can not happen.
+ */
+ ASSERT(slot <= last_slot);
+ if (WARN_ON(slot > last_slot))
+ return -ENOENT;
+
+ nitems = 1;
+ curr = item;
+ list_add_tail(&curr->tree_list, &batch_list);
+
+ /*
+ * Keep checking if the next delayed item matches the next item in the
+ * leaf - if so, we can add it to the batch of items to delete from the
+ * leaf.
+ */
+ while (slot < last_slot) {
+ struct btrfs_key key;
+
+ next = __btrfs_next_delayed_item(curr);
+ if (!next)
+ break;
+
+ slot++;
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+ if (key.objectid != ino ||
+ key.type != BTRFS_DIR_INDEX_KEY ||
+ key.offset != next->index)
+ break;
+ nitems++;
+ curr = next;
+ list_add_tail(&curr->tree_list, &batch_list);
+ total_reserved_size += curr->bytes_reserved;
+ }
+
+ ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
+ if (ret)
+ return ret;
+
+ /* In case of BTRFS_FS_LOG_RECOVERING items won't have reserved space */
+ if (total_reserved_size > 0) {
+ /*
+ * Check btrfs_delayed_item_reserve_metadata() to see why we
+ * don't need to release/reserve qgroup space.
+ */
+ trace_btrfs_space_reservation(fs_info, "delayed_item", ino,
+ total_reserved_size, 0);
+ btrfs_block_rsv_release(fs_info, &fs_info->delayed_block_rsv,
+ total_reserved_size, NULL);
+ }
+
+ list_for_each_entry_safe(curr, next, &batch_list, tree_list) {
+ list_del(&curr->tree_list);
+ btrfs_release_delayed_item(curr);
+ }
+
+ return 0;
+}
+
+static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
+ struct btrfs_path *path,
+ struct btrfs_root *root,
+ struct btrfs_delayed_node *node)
+{
+ struct btrfs_key key;
+ int ret = 0;
+
+ key.objectid = node->inode_id;
+ key.type = BTRFS_DIR_INDEX_KEY;
+
+ while (ret == 0) {
+ struct btrfs_delayed_item *item;
+
+ mutex_lock(&node->mutex);
+ item = __btrfs_first_delayed_deletion_item(node);
+ if (!item) {
+ mutex_unlock(&node->mutex);
+ break;
+ }
+
+ key.offset = item->index;
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret > 0) {
+ /*
+ * There's no matching item in the leaf. This means we
+ * have already deleted this item in a past run of the
+ * delayed items. We ignore errors when running delayed
+ * items from an async context, through a work queue job
+ * running btrfs_async_run_delayed_root(), and don't
+ * release delayed items that failed to complete. This
+ * is because we will retry later, and at transaction
+ * commit time we always run delayed items and will
+ * then deal with errors if they fail to run again.
+ *
+ * So just release delayed items for which we can't find
+ * an item in the tree, and move to the next item.
+ */
+ btrfs_release_path(path);
+ btrfs_release_delayed_item(item);
+ ret = 0;
+ } else if (ret == 0) {
+ ret = btrfs_batch_delete_items(trans, root, path, item);
+ btrfs_release_path(path);
+ }
+
+ /*
+ * We unlock and relock on each iteration, this is to prevent
+ * blocking other tasks for too long while we are being run from
+ * the async context (work queue job). Those tasks are typically
+ * running system calls like creat/mkdir/rename/unlink/etc which
+ * need to add delayed items to this delayed node.
+ */
+ mutex_unlock(&node->mutex);
+ }
+
+ return ret;
+}
+
+static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
+{
+ struct btrfs_delayed_root *delayed_root;
+
+ if (delayed_node &&
+ test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
+ BUG_ON(!delayed_node->root);
+ clear_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
+ delayed_node->count--;
+
+ delayed_root = delayed_node->root->fs_info->delayed_root;
+ finish_one_item(delayed_root);
+ }
+}
+
+static void btrfs_release_delayed_iref(struct btrfs_delayed_node *delayed_node)
+{
+
+ if (test_and_clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags)) {
+ struct btrfs_delayed_root *delayed_root;
+
+ ASSERT(delayed_node->root);
+ delayed_node->count--;
+
+ delayed_root = delayed_node->root->fs_info->delayed_root;
+ finish_one_item(delayed_root);
+ }
+}
+
+static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_delayed_node *node)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_key key;
+ struct btrfs_inode_item *inode_item;
+ struct extent_buffer *leaf;
+ int mod;
+ int ret;
+
+ key.objectid = node->inode_id;
+ key.type = BTRFS_INODE_ITEM_KEY;
+ key.offset = 0;
+
+ if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
+ mod = -1;
+ else
+ mod = 1;
+
+ ret = btrfs_lookup_inode(trans, root, path, &key, mod);
+ if (ret > 0)
+ ret = -ENOENT;
+ if (ret < 0)
+ goto out;
+
+ leaf = path->nodes[0];
+ inode_item = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_inode_item);
+ write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
+ sizeof(struct btrfs_inode_item));
+ btrfs_mark_buffer_dirty(leaf);
+
+ if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
+ goto out;
+
+ path->slots[0]++;
+ if (path->slots[0] >= btrfs_header_nritems(leaf))
+ goto search;
+again:
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+ if (key.objectid != node->inode_id)
+ goto out;
+
+ if (key.type != BTRFS_INODE_REF_KEY &&
+ key.type != BTRFS_INODE_EXTREF_KEY)
+ goto out;
+
+ /*
+ * Delayed iref deletion is for the inode who has only one link,
+ * so there is only one iref. The case that several irefs are
+ * in the same item doesn't exist.
+ */
+ btrfs_del_item(trans, root, path);
+out:
+ btrfs_release_delayed_iref(node);
+ btrfs_release_path(path);
+err_out:
+ btrfs_delayed_inode_release_metadata(fs_info, node, (ret < 0));
+ btrfs_release_delayed_inode(node);
+
+ /*
+ * If we fail to update the delayed inode we need to abort the
+ * transaction, because we could leave the inode with the improper
+ * counts behind.
+ */
+ if (ret && ret != -ENOENT)
+ btrfs_abort_transaction(trans, ret);
+
+ return ret;
+
+search:
+ btrfs_release_path(path);
+
+ key.type = BTRFS_INODE_EXTREF_KEY;
+ key.offset = -1;
+
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret < 0)
+ goto err_out;
+ ASSERT(ret);
+
+ ret = 0;
+ leaf = path->nodes[0];
+ path->slots[0]--;
+ goto again;
+}
+
+static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_delayed_node *node)
+{
+ int ret;
+
+ mutex_lock(&node->mutex);
+ if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &node->flags)) {
+ mutex_unlock(&node->mutex);
+ return 0;
+ }
+
+ ret = __btrfs_update_delayed_inode(trans, root, path, node);
+ mutex_unlock(&node->mutex);
+ return ret;
+}
+
+static inline int
+__btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
+ struct btrfs_path *path,
+ struct btrfs_delayed_node *node)
+{
+ int ret;
+
+ ret = btrfs_insert_delayed_items(trans, path, node->root, node);
+ if (ret)
+ return ret;
+
+ ret = btrfs_delete_delayed_items(trans, path, node->root, node);
+ if (ret)
+ return ret;
+
+ ret = btrfs_update_delayed_inode(trans, node->root, path, node);
+ return ret;
+}
+
+/*
+ * Called when committing the transaction.
+ * Returns 0 on success.
+ * Returns < 0 on error and returns with an aborted transaction with any
+ * outstanding delayed items cleaned up.
+ */
+static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans, int nr)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_delayed_root *delayed_root;
+ struct btrfs_delayed_node *curr_node, *prev_node;
+ struct btrfs_path *path;
+ struct btrfs_block_rsv *block_rsv;
+ int ret = 0;
+ bool count = (nr > 0);
+
+ if (TRANS_ABORTED(trans))
+ return -EIO;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ block_rsv = trans->block_rsv;
+ trans->block_rsv = &fs_info->delayed_block_rsv;
+
+ delayed_root = fs_info->delayed_root;
+
+ curr_node = btrfs_first_delayed_node(delayed_root);
+ while (curr_node && (!count || nr--)) {
+ ret = __btrfs_commit_inode_delayed_items(trans, path,
+ curr_node);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ break;
+ }
+
+ prev_node = curr_node;
+ curr_node = btrfs_next_delayed_node(curr_node);
+ /*
+ * See the comment below about releasing path before releasing
+ * node. If the commit of delayed items was successful the path
+ * should always be released, but in case of an error, it may
+ * point to locked extent buffers (a leaf at the very least).
+ */
+ ASSERT(path->nodes[0] == NULL);
+ btrfs_release_delayed_node(prev_node);
+ }
+
+ /*
+ * Release the path to avoid a potential deadlock and lockdep splat when
+ * releasing the delayed node, as that requires taking the delayed node's
+ * mutex. If another task starts running delayed items before we take
+ * the mutex, it will first lock the mutex and then it may try to lock
+ * the same btree path (leaf).
+ */
+ btrfs_free_path(path);
+
+ if (curr_node)
+ btrfs_release_delayed_node(curr_node);
+ trans->block_rsv = block_rsv;
+
+ return ret;
+}
+
+int btrfs_run_delayed_items(struct btrfs_trans_handle *trans)
+{
+ return __btrfs_run_delayed_items(trans, -1);
+}
+
+int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans, int nr)
+{
+ return __btrfs_run_delayed_items(trans, nr);
+}
+
+int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
+ struct btrfs_inode *inode)
+{
+ struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
+ struct btrfs_path *path;
+ struct btrfs_block_rsv *block_rsv;
+ int ret;
+
+ if (!delayed_node)
+ return 0;
+
+ mutex_lock(&delayed_node->mutex);
+ if (!delayed_node->count) {
+ mutex_unlock(&delayed_node->mutex);
+ btrfs_release_delayed_node(delayed_node);
+ return 0;
+ }
+ mutex_unlock(&delayed_node->mutex);
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ btrfs_release_delayed_node(delayed_node);
+ return -ENOMEM;
+ }
+
+ block_rsv = trans->block_rsv;
+ trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
+
+ ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
+
+ btrfs_release_delayed_node(delayed_node);
+ btrfs_free_path(path);
+ trans->block_rsv = block_rsv;
+
+ return ret;
+}
+
+int btrfs_commit_inode_delayed_inode(struct btrfs_inode *inode)
+{
+ struct btrfs_fs_info *fs_info = inode->root->fs_info;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
+ struct btrfs_path *path;
+ struct btrfs_block_rsv *block_rsv;
+ int ret;
+
+ if (!delayed_node)
+ return 0;
+
+ mutex_lock(&delayed_node->mutex);
+ if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
+ mutex_unlock(&delayed_node->mutex);
+ btrfs_release_delayed_node(delayed_node);
+ return 0;
+ }
+ mutex_unlock(&delayed_node->mutex);
+
+ trans = btrfs_join_transaction(delayed_node->root);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto trans_out;
+ }
+
+ block_rsv = trans->block_rsv;
+ trans->block_rsv = &fs_info->delayed_block_rsv;
+
+ mutex_lock(&delayed_node->mutex);
+ if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags))
+ ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
+ path, delayed_node);
+ else
+ ret = 0;
+ mutex_unlock(&delayed_node->mutex);
+
+ btrfs_free_path(path);
+ trans->block_rsv = block_rsv;
+trans_out:
+ btrfs_end_transaction(trans);
+ btrfs_btree_balance_dirty(fs_info);
+out:
+ btrfs_release_delayed_node(delayed_node);
+
+ return ret;
+}
+
+void btrfs_remove_delayed_node(struct btrfs_inode *inode)
+{
+ struct btrfs_delayed_node *delayed_node;
+
+ delayed_node = READ_ONCE(inode->delayed_node);
+ if (!delayed_node)
+ return;
+
+ inode->delayed_node = NULL;
+ btrfs_release_delayed_node(delayed_node);
+}
+
+struct btrfs_async_delayed_work {
+ struct btrfs_delayed_root *delayed_root;
+ int nr;
+ struct btrfs_work work;
+};
+
+static void btrfs_async_run_delayed_root(struct btrfs_work *work)
+{
+ struct btrfs_async_delayed_work *async_work;
+ struct btrfs_delayed_root *delayed_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_path *path;
+ struct btrfs_delayed_node *delayed_node = NULL;
+ struct btrfs_root *root;
+ struct btrfs_block_rsv *block_rsv;
+ int total_done = 0;
+
+ async_work = container_of(work, struct btrfs_async_delayed_work, work);
+ delayed_root = async_work->delayed_root;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ goto out;
+
+ do {
+ if (atomic_read(&delayed_root->items) <
+ BTRFS_DELAYED_BACKGROUND / 2)
+ break;
+
+ delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
+ if (!delayed_node)
+ break;
+
+ root = delayed_node->root;
+
+ trans = btrfs_join_transaction(root);
+ if (IS_ERR(trans)) {
+ btrfs_release_path(path);
+ btrfs_release_prepared_delayed_node(delayed_node);
+ total_done++;
+ continue;
+ }
+
+ block_rsv = trans->block_rsv;
+ trans->block_rsv = &root->fs_info->delayed_block_rsv;
+
+ __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
+
+ trans->block_rsv = block_rsv;
+ btrfs_end_transaction(trans);
+ btrfs_btree_balance_dirty_nodelay(root->fs_info);
+
+ btrfs_release_path(path);
+ btrfs_release_prepared_delayed_node(delayed_node);
+ total_done++;
+
+ } while ((async_work->nr == 0 && total_done < BTRFS_DELAYED_WRITEBACK)
+ || total_done < async_work->nr);
+
+ btrfs_free_path(path);
+out:
+ wake_up(&delayed_root->wait);
+ kfree(async_work);
+}
+
+
+static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
+ struct btrfs_fs_info *fs_info, int nr)
+{
+ struct btrfs_async_delayed_work *async_work;
+
+ async_work = kmalloc(sizeof(*async_work), GFP_NOFS);
+ if (!async_work)
+ return -ENOMEM;
+
+ async_work->delayed_root = delayed_root;
+ btrfs_init_work(&async_work->work, btrfs_async_run_delayed_root, NULL,
+ NULL);
+ async_work->nr = nr;
+
+ btrfs_queue_work(fs_info->delayed_workers, &async_work->work);
+ return 0;
+}
+
+void btrfs_assert_delayed_root_empty(struct btrfs_fs_info *fs_info)
+{
+ WARN_ON(btrfs_first_delayed_node(fs_info->delayed_root));
+}
+
+static int could_end_wait(struct btrfs_delayed_root *delayed_root, int seq)
+{
+ int val = atomic_read(&delayed_root->items_seq);
+
+ if (val < seq || val >= seq + BTRFS_DELAYED_BATCH)
+ return 1;
+
+ if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
+ return 1;
+
+ return 0;
+}
+
+void btrfs_balance_delayed_items(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_delayed_root *delayed_root = fs_info->delayed_root;
+
+ if ((atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND) ||
+ btrfs_workqueue_normal_congested(fs_info->delayed_workers))
+ return;
+
+ if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
+ int seq;
+ int ret;
+
+ seq = atomic_read(&delayed_root->items_seq);
+
+ ret = btrfs_wq_run_delayed_node(delayed_root, fs_info, 0);
+ if (ret)
+ return;
+
+ wait_event_interruptible(delayed_root->wait,
+ could_end_wait(delayed_root, seq));
+ return;
+ }
+
+ btrfs_wq_run_delayed_node(delayed_root, fs_info, BTRFS_DELAYED_BATCH);
+}
+
+static void btrfs_release_dir_index_item_space(struct btrfs_trans_handle *trans)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ const u64 bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
+
+ if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
+ return;
+
+ /*
+ * Adding the new dir index item does not require touching another
+ * leaf, so we can release 1 unit of metadata that was previously
+ * reserved when starting the transaction. This applies only to
+ * the case where we had a transaction start and excludes the
+ * transaction join case (when replaying log trees).
+ */
+ trace_btrfs_space_reservation(fs_info, "transaction",
+ trans->transid, bytes, 0);
+ btrfs_block_rsv_release(fs_info, trans->block_rsv, bytes, NULL);
+ ASSERT(trans->bytes_reserved >= bytes);
+ trans->bytes_reserved -= bytes;
+}
+
+/* Will return 0, -ENOMEM or -EEXIST (index number collision, unexpected). */
+int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
+ const char *name, int name_len,
+ struct btrfs_inode *dir,
+ struct btrfs_disk_key *disk_key, u8 type,
+ u64 index)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ const unsigned int leaf_data_size = BTRFS_LEAF_DATA_SIZE(fs_info);
+ struct btrfs_delayed_node *delayed_node;
+ struct btrfs_delayed_item *delayed_item;
+ struct btrfs_dir_item *dir_item;
+ bool reserve_leaf_space;
+ u32 data_len;
+ int ret;
+
+ delayed_node = btrfs_get_or_create_delayed_node(dir);
+ if (IS_ERR(delayed_node))
+ return PTR_ERR(delayed_node);
+
+ delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len,
+ delayed_node,
+ BTRFS_DELAYED_INSERTION_ITEM);
+ if (!delayed_item) {
+ ret = -ENOMEM;
+ goto release_node;
+ }
+
+ delayed_item->index = index;
+
+ dir_item = (struct btrfs_dir_item *)delayed_item->data;
+ dir_item->location = *disk_key;
+ btrfs_set_stack_dir_transid(dir_item, trans->transid);
+ btrfs_set_stack_dir_data_len(dir_item, 0);
+ btrfs_set_stack_dir_name_len(dir_item, name_len);
+ btrfs_set_stack_dir_type(dir_item, type);
+ memcpy((char *)(dir_item + 1), name, name_len);
+
+ data_len = delayed_item->data_len + sizeof(struct btrfs_item);
+
+ mutex_lock(&delayed_node->mutex);
+
+ /*
+ * First attempt to insert the delayed item. This is to make the error
+ * handling path simpler in case we fail (-EEXIST). There's no risk of
+ * any other task coming in and running the delayed item before we do
+ * the metadata space reservation below, because we are holding the
+ * delayed node's mutex and that mutex must also be locked before the
+ * node's delayed items can be run.
+ */
+ ret = __btrfs_add_delayed_item(delayed_node, delayed_item);
+ if (unlikely(ret)) {
+ btrfs_err(trans->fs_info,
+"error adding delayed dir index item, name: %.*s, index: %llu, root: %llu, dir: %llu, dir->index_cnt: %llu, delayed_node->index_cnt: %llu, error: %d",
+ name_len, name, index, btrfs_root_id(delayed_node->root),
+ delayed_node->inode_id, dir->index_cnt,
+ delayed_node->index_cnt, ret);
+ btrfs_release_delayed_item(delayed_item);
+ btrfs_release_dir_index_item_space(trans);
+ mutex_unlock(&delayed_node->mutex);
+ goto release_node;
+ }
+
+ if (delayed_node->index_item_leaves == 0 ||
+ delayed_node->curr_index_batch_size + data_len > leaf_data_size) {
+ delayed_node->curr_index_batch_size = data_len;
+ reserve_leaf_space = true;
+ } else {
+ delayed_node->curr_index_batch_size += data_len;
+ reserve_leaf_space = false;
+ }
+
+ if (reserve_leaf_space) {
+ ret = btrfs_delayed_item_reserve_metadata(trans, delayed_item);
+ /*
+ * Space was reserved for a dir index item insertion when we
+ * started the transaction, so getting a failure here should be
+ * impossible.
+ */
+ if (WARN_ON(ret)) {
+ btrfs_release_delayed_item(delayed_item);
+ mutex_unlock(&delayed_node->mutex);
+ goto release_node;
+ }
+
+ delayed_node->index_item_leaves++;
+ } else {
+ btrfs_release_dir_index_item_space(trans);
+ }
+ mutex_unlock(&delayed_node->mutex);
+
+release_node:
+ btrfs_release_delayed_node(delayed_node);
+ return ret;
+}
+
+static int btrfs_delete_delayed_insertion_item(struct btrfs_fs_info *fs_info,
+ struct btrfs_delayed_node *node,
+ u64 index)
+{
+ struct btrfs_delayed_item *item;
+
+ mutex_lock(&node->mutex);
+ item = __btrfs_lookup_delayed_item(&node->ins_root.rb_root, index);
+ if (!item) {
+ mutex_unlock(&node->mutex);
+ return 1;
+ }
+
+ /*
+ * For delayed items to insert, we track reserved metadata bytes based
+ * on the number of leaves that we will use.
+ * See btrfs_insert_delayed_dir_index() and
+ * btrfs_delayed_item_reserve_metadata()).
+ */
+ ASSERT(item->bytes_reserved == 0);
+ ASSERT(node->index_item_leaves > 0);
+
+ /*
+ * If there's only one leaf reserved, we can decrement this item from the
+ * current batch, otherwise we can not because we don't know which leaf
+ * it belongs to. With the current limit on delayed items, we rarely
+ * accumulate enough dir index items to fill more than one leaf (even
+ * when using a leaf size of 4K).
+ */
+ if (node->index_item_leaves == 1) {
+ const u32 data_len = item->data_len + sizeof(struct btrfs_item);
+
+ ASSERT(node->curr_index_batch_size >= data_len);
+ node->curr_index_batch_size -= data_len;
+ }
+
+ btrfs_release_delayed_item(item);
+
+ /* If we now have no more dir index items, we can release all leaves. */
+ if (RB_EMPTY_ROOT(&node->ins_root.rb_root)) {
+ btrfs_delayed_item_release_leaves(node, node->index_item_leaves);
+ node->index_item_leaves = 0;
+ }
+
+ mutex_unlock(&node->mutex);
+ return 0;
+}
+
+int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
+ struct btrfs_inode *dir, u64 index)
+{
+ struct btrfs_delayed_node *node;
+ struct btrfs_delayed_item *item;
+ int ret;
+
+ node = btrfs_get_or_create_delayed_node(dir);
+ if (IS_ERR(node))
+ return PTR_ERR(node);
+
+ ret = btrfs_delete_delayed_insertion_item(trans->fs_info, node, index);
+ if (!ret)
+ goto end;
+
+ item = btrfs_alloc_delayed_item(0, node, BTRFS_DELAYED_DELETION_ITEM);
+ if (!item) {
+ ret = -ENOMEM;
+ goto end;
+ }
+
+ item->index = index;
+
+ ret = btrfs_delayed_item_reserve_metadata(trans, item);
+ /*
+ * we have reserved enough space when we start a new transaction,
+ * so reserving metadata failure is impossible.
+ */
+ if (ret < 0) {
+ btrfs_err(trans->fs_info,
+"metadata reservation failed for delayed dir item deltiona, should have been reserved");
+ btrfs_release_delayed_item(item);
+ goto end;
+ }
+
+ mutex_lock(&node->mutex);
+ ret = __btrfs_add_delayed_item(node, item);
+ if (unlikely(ret)) {
+ btrfs_err(trans->fs_info,
+ "err add delayed dir index item(index: %llu) into the deletion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
+ index, node->root->root_key.objectid,
+ node->inode_id, ret);
+ btrfs_delayed_item_release_metadata(dir->root, item);
+ btrfs_release_delayed_item(item);
+ }
+ mutex_unlock(&node->mutex);
+end:
+ btrfs_release_delayed_node(node);
+ return ret;
+}
+
+int btrfs_inode_delayed_dir_index_count(struct btrfs_inode *inode)
+{
+ struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
+
+ if (!delayed_node)
+ return -ENOENT;
+
+ /*
+ * Since we have held i_mutex of this directory, it is impossible that
+ * a new directory index is added into the delayed node and index_cnt
+ * is updated now. So we needn't lock the delayed node.
+ */
+ if (!delayed_node->index_cnt) {
+ btrfs_release_delayed_node(delayed_node);
+ return -EINVAL;
+ }
+
+ inode->index_cnt = delayed_node->index_cnt;
+ btrfs_release_delayed_node(delayed_node);
+ return 0;
+}
+
+bool btrfs_readdir_get_delayed_items(struct inode *inode,
+ u64 last_index,
+ struct list_head *ins_list,
+ struct list_head *del_list)
+{
+ struct btrfs_delayed_node *delayed_node;
+ struct btrfs_delayed_item *item;
+
+ delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
+ if (!delayed_node)
+ return false;
+
+ /*
+ * We can only do one readdir with delayed items at a time because of
+ * item->readdir_list.
+ */
+ btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED);
+ btrfs_inode_lock(inode, 0);
+
+ mutex_lock(&delayed_node->mutex);
+ item = __btrfs_first_delayed_insertion_item(delayed_node);
+ while (item && item->index <= last_index) {
+ refcount_inc(&item->refs);
+ list_add_tail(&item->readdir_list, ins_list);
+ item = __btrfs_next_delayed_item(item);
+ }
+
+ item = __btrfs_first_delayed_deletion_item(delayed_node);
+ while (item && item->index <= last_index) {
+ refcount_inc(&item->refs);
+ list_add_tail(&item->readdir_list, del_list);
+ item = __btrfs_next_delayed_item(item);
+ }
+ mutex_unlock(&delayed_node->mutex);
+ /*
+ * This delayed node is still cached in the btrfs inode, so refs
+ * must be > 1 now, and we needn't check it is going to be freed
+ * or not.
+ *
+ * Besides that, this function is used to read dir, we do not
+ * insert/delete delayed items in this period. So we also needn't
+ * requeue or dequeue this delayed node.
+ */
+ refcount_dec(&delayed_node->refs);
+
+ return true;
+}
+
+void btrfs_readdir_put_delayed_items(struct inode *inode,
+ struct list_head *ins_list,
+ struct list_head *del_list)
+{
+ struct btrfs_delayed_item *curr, *next;
+
+ list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
+ list_del(&curr->readdir_list);
+ if (refcount_dec_and_test(&curr->refs))
+ kfree(curr);
+ }
+
+ list_for_each_entry_safe(curr, next, del_list, readdir_list) {
+ list_del(&curr->readdir_list);
+ if (refcount_dec_and_test(&curr->refs))
+ kfree(curr);
+ }
+
+ /*
+ * The VFS is going to do up_read(), so we need to downgrade back to a
+ * read lock.
+ */
+ downgrade_write(&inode->i_rwsem);
+}
+
+int btrfs_should_delete_dir_index(struct list_head *del_list,
+ u64 index)
+{
+ struct btrfs_delayed_item *curr;
+ int ret = 0;
+
+ list_for_each_entry(curr, del_list, readdir_list) {
+ if (curr->index > index)
+ break;
+ if (curr->index == index) {
+ ret = 1;
+ break;
+ }
+ }
+ return ret;
+}
+
+/*
+ * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
+ *
+ */
+int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
+ struct list_head *ins_list)
+{
+ struct btrfs_dir_item *di;
+ struct btrfs_delayed_item *curr, *next;
+ struct btrfs_key location;
+ char *name;
+ int name_len;
+ int over = 0;
+ unsigned char d_type;
+
+ if (list_empty(ins_list))
+ return 0;
+
+ /*
+ * Changing the data of the delayed item is impossible. So
+ * we needn't lock them. And we have held i_mutex of the
+ * directory, nobody can delete any directory indexes now.
+ */
+ list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
+ list_del(&curr->readdir_list);
+
+ if (curr->index < ctx->pos) {
+ if (refcount_dec_and_test(&curr->refs))
+ kfree(curr);
+ continue;
+ }
+
+ ctx->pos = curr->index;
+
+ di = (struct btrfs_dir_item *)curr->data;
+ name = (char *)(di + 1);
+ name_len = btrfs_stack_dir_name_len(di);
+
+ d_type = fs_ftype_to_dtype(di->type);
+ btrfs_disk_key_to_cpu(&location, &di->location);
+
+ over = !dir_emit(ctx, name, name_len,
+ location.objectid, d_type);
+
+ if (refcount_dec_and_test(&curr->refs))
+ kfree(curr);
+
+ if (over)
+ return 1;
+ ctx->pos++;
+ }
+ return 0;
+}
+
+static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
+ struct btrfs_inode_item *inode_item,
+ struct inode *inode)
+{
+ u64 flags;
+
+ btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
+ btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
+ btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
+ btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
+ btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
+ btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
+ btrfs_set_stack_inode_generation(inode_item,
+ BTRFS_I(inode)->generation);
+ btrfs_set_stack_inode_sequence(inode_item,
+ inode_peek_iversion(inode));
+ btrfs_set_stack_inode_transid(inode_item, trans->transid);
+ btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
+ flags = btrfs_inode_combine_flags(BTRFS_I(inode)->flags,
+ BTRFS_I(inode)->ro_flags);
+ btrfs_set_stack_inode_flags(inode_item, flags);
+ btrfs_set_stack_inode_block_group(inode_item, 0);
+
+ btrfs_set_stack_timespec_sec(&inode_item->atime,
+ inode->i_atime.tv_sec);
+ btrfs_set_stack_timespec_nsec(&inode_item->atime,
+ inode->i_atime.tv_nsec);
+
+ btrfs_set_stack_timespec_sec(&inode_item->mtime,
+ inode->i_mtime.tv_sec);
+ btrfs_set_stack_timespec_nsec(&inode_item->mtime,
+ inode->i_mtime.tv_nsec);
+
+ btrfs_set_stack_timespec_sec(&inode_item->ctime,
+ inode->i_ctime.tv_sec);
+ btrfs_set_stack_timespec_nsec(&inode_item->ctime,
+ inode->i_ctime.tv_nsec);
+
+ btrfs_set_stack_timespec_sec(&inode_item->otime,
+ BTRFS_I(inode)->i_otime.tv_sec);
+ btrfs_set_stack_timespec_nsec(&inode_item->otime,
+ BTRFS_I(inode)->i_otime.tv_nsec);
+}
+
+int btrfs_fill_inode(struct inode *inode, u32 *rdev)
+{
+ struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
+ struct btrfs_delayed_node *delayed_node;
+ struct btrfs_inode_item *inode_item;
+
+ delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
+ if (!delayed_node)
+ return -ENOENT;
+
+ mutex_lock(&delayed_node->mutex);
+ if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
+ mutex_unlock(&delayed_node->mutex);
+ btrfs_release_delayed_node(delayed_node);
+ return -ENOENT;
+ }
+
+ inode_item = &delayed_node->inode_item;
+
+ i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
+ i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
+ btrfs_i_size_write(BTRFS_I(inode), btrfs_stack_inode_size(inode_item));
+ btrfs_inode_set_file_extent_range(BTRFS_I(inode), 0,
+ round_up(i_size_read(inode), fs_info->sectorsize));
+ inode->i_mode = btrfs_stack_inode_mode(inode_item);
+ set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
+ inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
+ BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
+ BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
+
+ inode_set_iversion_queried(inode,
+ btrfs_stack_inode_sequence(inode_item));
+ inode->i_rdev = 0;
+ *rdev = btrfs_stack_inode_rdev(inode_item);
+ btrfs_inode_split_flags(btrfs_stack_inode_flags(inode_item),
+ &BTRFS_I(inode)->flags, &BTRFS_I(inode)->ro_flags);
+
+ inode->i_atime.tv_sec = btrfs_stack_timespec_sec(&inode_item->atime);
+ inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->atime);
+
+ inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(&inode_item->mtime);
+ inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->mtime);
+
+ inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(&inode_item->ctime);
+ inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->ctime);
+
+ BTRFS_I(inode)->i_otime.tv_sec =
+ btrfs_stack_timespec_sec(&inode_item->otime);
+ BTRFS_I(inode)->i_otime.tv_nsec =
+ btrfs_stack_timespec_nsec(&inode_item->otime);
+
+ inode->i_generation = BTRFS_I(inode)->generation;
+ BTRFS_I(inode)->index_cnt = (u64)-1;
+
+ mutex_unlock(&delayed_node->mutex);
+ btrfs_release_delayed_node(delayed_node);
+ return 0;
+}
+
+int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_inode *inode)
+{
+ struct btrfs_delayed_node *delayed_node;
+ int ret = 0;
+
+ delayed_node = btrfs_get_or_create_delayed_node(inode);
+ if (IS_ERR(delayed_node))
+ return PTR_ERR(delayed_node);
+
+ mutex_lock(&delayed_node->mutex);
+ if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
+ fill_stack_inode_item(trans, &delayed_node->inode_item,
+ &inode->vfs_inode);
+ goto release_node;
+ }
+
+ ret = btrfs_delayed_inode_reserve_metadata(trans, root, delayed_node);
+ if (ret)
+ goto release_node;
+
+ fill_stack_inode_item(trans, &delayed_node->inode_item, &inode->vfs_inode);
+ set_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
+ delayed_node->count++;
+ atomic_inc(&root->fs_info->delayed_root->items);
+release_node:
+ mutex_unlock(&delayed_node->mutex);
+ btrfs_release_delayed_node(delayed_node);
+ return ret;
+}
+
+int btrfs_delayed_delete_inode_ref(struct btrfs_inode *inode)
+{
+ struct btrfs_fs_info *fs_info = inode->root->fs_info;
+ struct btrfs_delayed_node *delayed_node;
+
+ /*
+ * we don't do delayed inode updates during log recovery because it
+ * leads to enospc problems. This means we also can't do
+ * delayed inode refs
+ */
+ if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
+ return -EAGAIN;
+
+ delayed_node = btrfs_get_or_create_delayed_node(inode);
+ if (IS_ERR(delayed_node))
+ return PTR_ERR(delayed_node);
+
+ /*
+ * We don't reserve space for inode ref deletion is because:
+ * - We ONLY do async inode ref deletion for the inode who has only
+ * one link(i_nlink == 1), it means there is only one inode ref.
+ * And in most case, the inode ref and the inode item are in the
+ * same leaf, and we will deal with them at the same time.
+ * Since we are sure we will reserve the space for the inode item,
+ * it is unnecessary to reserve space for inode ref deletion.
+ * - If the inode ref and the inode item are not in the same leaf,
+ * We also needn't worry about enospc problem, because we reserve
+ * much more space for the inode update than it needs.
+ * - At the worst, we can steal some space from the global reservation.
+ * It is very rare.
+ */
+ mutex_lock(&delayed_node->mutex);
+ if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
+ goto release_node;
+
+ set_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
+ delayed_node->count++;
+ atomic_inc(&fs_info->delayed_root->items);
+release_node:
+ mutex_unlock(&delayed_node->mutex);
+ btrfs_release_delayed_node(delayed_node);
+ return 0;
+}
+
+static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
+{
+ struct btrfs_root *root = delayed_node->root;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_delayed_item *curr_item, *prev_item;
+
+ mutex_lock(&delayed_node->mutex);
+ curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
+ while (curr_item) {
+ prev_item = curr_item;
+ curr_item = __btrfs_next_delayed_item(prev_item);
+ btrfs_release_delayed_item(prev_item);
+ }
+
+ if (delayed_node->index_item_leaves > 0) {
+ btrfs_delayed_item_release_leaves(delayed_node,
+ delayed_node->index_item_leaves);
+ delayed_node->index_item_leaves = 0;
+ }
+
+ curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
+ while (curr_item) {
+ btrfs_delayed_item_release_metadata(root, curr_item);
+ prev_item = curr_item;
+ curr_item = __btrfs_next_delayed_item(prev_item);
+ btrfs_release_delayed_item(prev_item);
+ }
+
+ btrfs_release_delayed_iref(delayed_node);
+
+ if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
+ btrfs_delayed_inode_release_metadata(fs_info, delayed_node, false);
+ btrfs_release_delayed_inode(delayed_node);
+ }
+ mutex_unlock(&delayed_node->mutex);
+}
+
+void btrfs_kill_delayed_inode_items(struct btrfs_inode *inode)
+{
+ struct btrfs_delayed_node *delayed_node;
+
+ delayed_node = btrfs_get_delayed_node(inode);
+ if (!delayed_node)
+ return;
+
+ __btrfs_kill_delayed_node(delayed_node);
+ btrfs_release_delayed_node(delayed_node);
+}
+
+void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
+{
+ u64 inode_id = 0;
+ struct btrfs_delayed_node *delayed_nodes[8];
+ int i, n;
+
+ while (1) {
+ spin_lock(&root->inode_lock);
+ n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
+ (void **)delayed_nodes, inode_id,
+ ARRAY_SIZE(delayed_nodes));
+ if (!n) {
+ spin_unlock(&root->inode_lock);
+ break;
+ }
+
+ inode_id = delayed_nodes[n - 1]->inode_id + 1;
+ for (i = 0; i < n; i++) {
+ /*
+ * Don't increase refs in case the node is dead and
+ * about to be removed from the tree in the loop below
+ */
+ if (!refcount_inc_not_zero(&delayed_nodes[i]->refs))
+ delayed_nodes[i] = NULL;
+ }
+ spin_unlock(&root->inode_lock);
+
+ for (i = 0; i < n; i++) {
+ if (!delayed_nodes[i])
+ continue;
+ __btrfs_kill_delayed_node(delayed_nodes[i]);
+ btrfs_release_delayed_node(delayed_nodes[i]);
+ }
+ }
+}
+
+void btrfs_destroy_delayed_inodes(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_delayed_node *curr_node, *prev_node;
+
+ curr_node = btrfs_first_delayed_node(fs_info->delayed_root);
+ while (curr_node) {
+ __btrfs_kill_delayed_node(curr_node);
+
+ prev_node = curr_node;
+ curr_node = btrfs_next_delayed_node(curr_node);
+ btrfs_release_delayed_node(prev_node);
+ }
+}
+
+void btrfs_log_get_delayed_items(struct btrfs_inode *inode,
+ struct list_head *ins_list,
+ struct list_head *del_list)
+{
+ struct btrfs_delayed_node *node;
+ struct btrfs_delayed_item *item;
+
+ node = btrfs_get_delayed_node(inode);
+ if (!node)
+ return;
+
+ mutex_lock(&node->mutex);
+ item = __btrfs_first_delayed_insertion_item(node);
+ while (item) {
+ /*
+ * It's possible that the item is already in a log list. This
+ * can happen in case two tasks are trying to log the same
+ * directory. For example if we have tasks A and task B:
+ *
+ * Task A collected the delayed items into a log list while
+ * under the inode's log_mutex (at btrfs_log_inode()), but it
+ * only releases the items after logging the inodes they point
+ * to (if they are new inodes), which happens after unlocking
+ * the log mutex;
+ *
+ * Task B enters btrfs_log_inode() and acquires the log_mutex
+ * of the same directory inode, before task B releases the
+ * delayed items. This can happen for example when logging some
+ * inode we need to trigger logging of its parent directory, so
+ * logging two files that have the same parent directory can
+ * lead to this.
+ *
+ * If this happens, just ignore delayed items already in a log
+ * list. All the tasks logging the directory are under a log
+ * transaction and whichever finishes first can not sync the log
+ * before the other completes and leaves the log transaction.
+ */
+ if (!item->logged && list_empty(&item->log_list)) {
+ refcount_inc(&item->refs);
+ list_add_tail(&item->log_list, ins_list);
+ }
+ item = __btrfs_next_delayed_item(item);
+ }
+
+ item = __btrfs_first_delayed_deletion_item(node);
+ while (item) {
+ /* It may be non-empty, for the same reason mentioned above. */
+ if (!item->logged && list_empty(&item->log_list)) {
+ refcount_inc(&item->refs);
+ list_add_tail(&item->log_list, del_list);
+ }
+ item = __btrfs_next_delayed_item(item);
+ }
+ mutex_unlock(&node->mutex);
+
+ /*
+ * We are called during inode logging, which means the inode is in use
+ * and can not be evicted before we finish logging the inode. So we never
+ * have the last reference on the delayed inode.
+ * Also, we don't use btrfs_release_delayed_node() because that would
+ * requeue the delayed inode (change its order in the list of prepared
+ * nodes) and we don't want to do such change because we don't create or
+ * delete delayed items.
+ */
+ ASSERT(refcount_read(&node->refs) > 1);
+ refcount_dec(&node->refs);
+}
+
+void btrfs_log_put_delayed_items(struct btrfs_inode *inode,
+ struct list_head *ins_list,
+ struct list_head *del_list)
+{
+ struct btrfs_delayed_node *node;
+ struct btrfs_delayed_item *item;
+ struct btrfs_delayed_item *next;
+
+ node = btrfs_get_delayed_node(inode);
+ if (!node)
+ return;
+
+ mutex_lock(&node->mutex);
+
+ list_for_each_entry_safe(item, next, ins_list, log_list) {
+ item->logged = true;
+ list_del_init(&item->log_list);
+ if (refcount_dec_and_test(&item->refs))
+ kfree(item);
+ }
+
+ list_for_each_entry_safe(item, next, del_list, log_list) {
+ item->logged = true;
+ list_del_init(&item->log_list);
+ if (refcount_dec_and_test(&item->refs))
+ kfree(item);
+ }
+
+ mutex_unlock(&node->mutex);
+
+ /*
+ * We are called during inode logging, which means the inode is in use
+ * and can not be evicted before we finish logging the inode. So we never
+ * have the last reference on the delayed inode.
+ * Also, we don't use btrfs_release_delayed_node() because that would
+ * requeue the delayed inode (change its order in the list of prepared
+ * nodes) and we don't want to do such change because we don't create or
+ * delete delayed items.
+ */
+ ASSERT(refcount_read(&node->refs) > 1);
+ refcount_dec(&node->refs);
+}