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-rw-r--r--kernel/fs/btrfs/delayed-inode.c1997
1 files changed, 1997 insertions, 0 deletions
diff --git a/kernel/fs/btrfs/delayed-inode.c b/kernel/fs/btrfs/delayed-inode.c
new file mode 100644
index 000000000..a2ae42720
--- /dev/null
+++ b/kernel/fs/btrfs/delayed-inode.c
@@ -0,0 +1,1997 @@
+/*
+ * Copyright (C) 2011 Fujitsu. All rights reserved.
+ * Written by Miao Xie <miaox@cn.fujitsu.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/slab.h>
+#include "delayed-inode.h"
+#include "disk-io.h"
+#include "transaction.h"
+#include "ctree.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_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+ NULL);
+ if (!delayed_node_cache)
+ return -ENOMEM;
+ return 0;
+}
+
+void btrfs_delayed_inode_exit(void)
+{
+ if (delayed_node_cache)
+ 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;
+ atomic_set(&delayed_node->refs, 0);
+ delayed_node->count = 0;
+ delayed_node->flags = 0;
+ delayed_node->ins_root = RB_ROOT;
+ delayed_node->del_root = RB_ROOT;
+ mutex_init(&delayed_node->mutex);
+ delayed_node->index_cnt = 0;
+ INIT_LIST_HEAD(&delayed_node->n_list);
+ INIT_LIST_HEAD(&delayed_node->p_list);
+ delayed_node->bytes_reserved = 0;
+ memset(&delayed_node->inode_item, 0, sizeof(delayed_node->inode_item));
+}
+
+static inline int btrfs_is_continuous_delayed_item(
+ struct btrfs_delayed_item *item1,
+ struct btrfs_delayed_item *item2)
+{
+ if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
+ item1->key.objectid == item2->key.objectid &&
+ item1->key.type == item2->key.type &&
+ item1->key.offset + 1 == item2->key.offset)
+ return 1;
+ return 0;
+}
+
+static inline struct btrfs_delayed_root *btrfs_get_delayed_root(
+ struct btrfs_root *root)
+{
+ return root->fs_info->delayed_root;
+}
+
+static struct btrfs_delayed_node *btrfs_get_delayed_node(struct inode *inode)
+{
+ struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
+ struct btrfs_root *root = btrfs_inode->root;
+ u64 ino = btrfs_ino(inode);
+ struct btrfs_delayed_node *node;
+
+ node = ACCESS_ONCE(btrfs_inode->delayed_node);
+ if (node) {
+ atomic_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) {
+ atomic_inc(&node->refs); /* can be accessed */
+ BUG_ON(btrfs_inode->delayed_node != node);
+ spin_unlock(&root->inode_lock);
+ return node;
+ }
+ btrfs_inode->delayed_node = node;
+ /* can be accessed and cached in the inode */
+ atomic_add(2, &node->refs);
+ 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 inode *inode)
+{
+ struct btrfs_delayed_node *node;
+ struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
+ struct btrfs_root *root = btrfs_inode->root;
+ u64 ino = btrfs_ino(inode);
+ int ret;
+
+again:
+ node = btrfs_get_delayed_node(inode);
+ if (node)
+ return node;
+
+ node = kmem_cache_alloc(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 */
+ atomic_add(2, &node->refs);
+
+ ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
+ 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);
+ atomic_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--;
+ atomic_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);
+ atomic_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);
+ atomic_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 (atomic_dec_and_test(&delayed_node->refs)) {
+ bool free = false;
+ struct btrfs_root *root = delayed_node->root;
+ spin_lock(&root->inode_lock);
+ if (atomic_read(&delayed_node->refs) == 0) {
+ radix_tree_delete(&root->delayed_nodes_tree,
+ delayed_node->inode_id);
+ free = true;
+ }
+ spin_unlock(&root->inode_lock);
+ if (free)
+ 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);
+ atomic_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(u32 data_len)
+{
+ struct btrfs_delayed_item *item;
+ item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
+ if (item) {
+ item->data_len = data_len;
+ item->ins_or_del = 0;
+ item->bytes_reserved = 0;
+ item->delayed_node = NULL;
+ atomic_set(&item->refs, 1);
+ }
+ return item;
+}
+
+/*
+ * __btrfs_lookup_delayed_item - look up the delayed item by key
+ * @delayed_node: pointer to the delayed node
+ * @key: the key to look up
+ * @prev: used to store the prev item if the right item isn't found
+ * @next: used to store the next item if the right item isn't found
+ *
+ * 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,
+ struct btrfs_key *key,
+ struct btrfs_delayed_item **prev,
+ struct btrfs_delayed_item **next)
+{
+ struct rb_node *node, *prev_node = NULL;
+ struct btrfs_delayed_item *delayed_item = NULL;
+ int ret = 0;
+
+ node = root->rb_node;
+
+ while (node) {
+ delayed_item = rb_entry(node, struct btrfs_delayed_item,
+ rb_node);
+ prev_node = node;
+ ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
+ if (ret < 0)
+ node = node->rb_right;
+ else if (ret > 0)
+ node = node->rb_left;
+ else
+ return delayed_item;
+ }
+
+ if (prev) {
+ if (!prev_node)
+ *prev = NULL;
+ else if (ret < 0)
+ *prev = delayed_item;
+ else if ((node = rb_prev(prev_node)) != NULL) {
+ *prev = rb_entry(node, struct btrfs_delayed_item,
+ rb_node);
+ } else
+ *prev = NULL;
+ }
+
+ if (next) {
+ if (!prev_node)
+ *next = NULL;
+ else if (ret > 0)
+ *next = delayed_item;
+ else if ((node = rb_next(prev_node)) != NULL) {
+ *next = rb_entry(node, struct btrfs_delayed_item,
+ rb_node);
+ } else
+ *next = NULL;
+ }
+ return NULL;
+}
+
+static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
+ struct btrfs_delayed_node *delayed_node,
+ struct btrfs_key *key)
+{
+ struct btrfs_delayed_item *item;
+
+ item = __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
+ NULL, NULL);
+ return item;
+}
+
+static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
+ struct btrfs_delayed_item *ins,
+ int action)
+{
+ struct rb_node **p, *node;
+ struct rb_node *parent_node = NULL;
+ struct rb_root *root;
+ struct btrfs_delayed_item *item;
+ int cmp;
+
+ if (action == BTRFS_DELAYED_INSERTION_ITEM)
+ root = &delayed_node->ins_root;
+ else if (action == BTRFS_DELAYED_DELETION_ITEM)
+ root = &delayed_node->del_root;
+ else
+ BUG();
+ p = &root->rb_node;
+ node = &ins->rb_node;
+
+ while (*p) {
+ parent_node = *p;
+ item = rb_entry(parent_node, struct btrfs_delayed_item,
+ rb_node);
+
+ cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
+ if (cmp < 0)
+ p = &(*p)->rb_right;
+ else if (cmp > 0)
+ p = &(*p)->rb_left;
+ else
+ return -EEXIST;
+ }
+
+ rb_link_node(node, parent_node, p);
+ rb_insert_color(node, root);
+ ins->delayed_node = delayed_node;
+ ins->ins_or_del = action;
+
+ if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
+ action == BTRFS_DELAYED_INSERTION_ITEM &&
+ ins->key.offset >= delayed_node->index_cnt)
+ delayed_node->index_cnt = ins->key.offset + 1;
+
+ delayed_node->count++;
+ atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
+ return 0;
+}
+
+static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
+ struct btrfs_delayed_item *item)
+{
+ return __btrfs_add_delayed_item(node, item,
+ BTRFS_DELAYED_INSERTION_ITEM);
+}
+
+static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
+ struct btrfs_delayed_item *item)
+{
+ return __btrfs_add_delayed_item(node, item,
+ BTRFS_DELAYED_DELETION_ITEM);
+}
+
+static void finish_one_item(struct btrfs_delayed_root *delayed_root)
+{
+ int seq = atomic_inc_return(&delayed_root->items_seq);
+ if ((atomic_dec_return(&delayed_root->items) <
+ BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) &&
+ waitqueue_active(&delayed_root->wait))
+ wake_up(&delayed_root->wait);
+}
+
+static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
+{
+ struct rb_root *root;
+ struct btrfs_delayed_root *delayed_root;
+
+ delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
+
+ BUG_ON(!delayed_root);
+ BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
+ delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
+
+ if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
+ root = &delayed_item->delayed_node->ins_root;
+ else
+ root = &delayed_item->delayed_node->del_root;
+
+ rb_erase(&delayed_item->rb_node, root);
+ delayed_item->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 (atomic_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(&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(&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_root *root,
+ struct btrfs_delayed_item *item)
+{
+ struct btrfs_block_rsv *src_rsv;
+ struct btrfs_block_rsv *dst_rsv;
+ u64 num_bytes;
+ int ret;
+
+ if (!trans->bytes_reserved)
+ return 0;
+
+ src_rsv = trans->block_rsv;
+ dst_rsv = &root->fs_info->delayed_block_rsv;
+
+ num_bytes = btrfs_calc_trans_metadata_size(root, 1);
+ ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
+ if (!ret) {
+ trace_btrfs_space_reservation(root->fs_info, "delayed_item",
+ item->key.objectid,
+ num_bytes, 1);
+ 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;
+
+ if (!item->bytes_reserved)
+ return;
+
+ rsv = &root->fs_info->delayed_block_rsv;
+ trace_btrfs_space_reservation(root->fs_info, "delayed_item",
+ item->key.objectid, item->bytes_reserved,
+ 0);
+ btrfs_block_rsv_release(root, rsv,
+ item->bytes_reserved);
+}
+
+static int btrfs_delayed_inode_reserve_metadata(
+ struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode,
+ struct btrfs_delayed_node *node)
+{
+ struct btrfs_block_rsv *src_rsv;
+ struct btrfs_block_rsv *dst_rsv;
+ u64 num_bytes;
+ int ret;
+ bool release = false;
+
+ src_rsv = trans->block_rsv;
+ dst_rsv = &root->fs_info->delayed_block_rsv;
+
+ num_bytes = btrfs_calc_trans_metadata_size(root, 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're accounted for.
+ */
+ if (!src_rsv || (!trans->bytes_reserved &&
+ src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
+ ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
+ BTRFS_RESERVE_NO_FLUSH);
+ /*
+ * Since we're under a transaction reserve_metadata_bytes could
+ * try to commit the transaction which will make it return
+ * EAGAIN to make us stop the transaction we have, so return
+ * ENOSPC instead so that btrfs_dirty_inode knows what to do.
+ */
+ if (ret == -EAGAIN)
+ ret = -ENOSPC;
+ if (!ret) {
+ node->bytes_reserved = num_bytes;
+ trace_btrfs_space_reservation(root->fs_info,
+ "delayed_inode",
+ btrfs_ino(inode),
+ num_bytes, 1);
+ }
+ return ret;
+ } else if (src_rsv->type == BTRFS_BLOCK_RSV_DELALLOC) {
+ spin_lock(&BTRFS_I(inode)->lock);
+ if (test_and_clear_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
+ &BTRFS_I(inode)->runtime_flags)) {
+ spin_unlock(&BTRFS_I(inode)->lock);
+ release = true;
+ goto migrate;
+ }
+ spin_unlock(&BTRFS_I(inode)->lock);
+
+ /* Ok we didn't have space pre-reserved. This shouldn't happen
+ * too often but it can happen if we do delalloc to an existing
+ * inode which gets dirtied because of the time update, and then
+ * isn't touched again until after the transaction commits and
+ * then we try to write out the data. First try to be nice and
+ * reserve something strictly for us. If not be a pain and try
+ * to steal from the delalloc block rsv.
+ */
+ ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
+ BTRFS_RESERVE_NO_FLUSH);
+ if (!ret)
+ goto out;
+
+ ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
+ if (!WARN_ON(ret))
+ goto out;
+
+ /*
+ * Ok this is a problem, let's just steal from the global rsv
+ * since this really shouldn't happen that often.
+ */
+ ret = btrfs_block_rsv_migrate(&root->fs_info->global_block_rsv,
+ dst_rsv, num_bytes);
+ goto out;
+ }
+
+migrate:
+ ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
+
+out:
+ /*
+ * Migrate only takes a reservation, it doesn't touch the size of the
+ * block_rsv. This is to simplify people who don't normally have things
+ * migrated from their block rsv. If they go to release their
+ * reservation, that will decrease the size as well, so if migrate
+ * reduced size we'd end up with a negative size. But for the
+ * delalloc_meta_reserved stuff we will only know to drop 1 reservation,
+ * but we could in fact do this reserve/migrate dance several times
+ * between the time we did the original reservation and we'd clean it
+ * up. So to take care of this, release the space for the meta
+ * reservation here. I think it may be time for a documentation page on
+ * how block rsvs. work.
+ */
+ if (!ret) {
+ trace_btrfs_space_reservation(root->fs_info, "delayed_inode",
+ btrfs_ino(inode), num_bytes, 1);
+ node->bytes_reserved = num_bytes;
+ }
+
+ if (release) {
+ trace_btrfs_space_reservation(root->fs_info, "delalloc",
+ btrfs_ino(inode), num_bytes, 0);
+ btrfs_block_rsv_release(root, src_rsv, num_bytes);
+ }
+
+ return ret;
+}
+
+static void btrfs_delayed_inode_release_metadata(struct btrfs_root *root,
+ struct btrfs_delayed_node *node)
+{
+ struct btrfs_block_rsv *rsv;
+
+ if (!node->bytes_reserved)
+ return;
+
+ rsv = &root->fs_info->delayed_block_rsv;
+ trace_btrfs_space_reservation(root->fs_info, "delayed_inode",
+ node->inode_id, node->bytes_reserved, 0);
+ btrfs_block_rsv_release(root, rsv,
+ node->bytes_reserved);
+ node->bytes_reserved = 0;
+}
+
+/*
+ * This helper will insert some continuous items into the same leaf according
+ * to the free space of the leaf.
+ */
+static int btrfs_batch_insert_items(struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_delayed_item *item)
+{
+ struct btrfs_delayed_item *curr, *next;
+ int free_space;
+ int total_data_size = 0, total_size = 0;
+ struct extent_buffer *leaf;
+ char *data_ptr;
+ struct btrfs_key *keys;
+ u32 *data_size;
+ struct list_head head;
+ int slot;
+ int nitems;
+ int i;
+ int ret = 0;
+
+ BUG_ON(!path->nodes[0]);
+
+ leaf = path->nodes[0];
+ free_space = btrfs_leaf_free_space(root, leaf);
+ INIT_LIST_HEAD(&head);
+
+ next = item;
+ nitems = 0;
+
+ /*
+ * count the number of the continuous items that we can insert in batch
+ */
+ while (total_size + next->data_len + sizeof(struct btrfs_item) <=
+ free_space) {
+ total_data_size += next->data_len;
+ total_size += next->data_len + sizeof(struct btrfs_item);
+ list_add_tail(&next->tree_list, &head);
+ nitems++;
+
+ curr = next;
+ next = __btrfs_next_delayed_item(curr);
+ if (!next)
+ break;
+
+ if (!btrfs_is_continuous_delayed_item(curr, next))
+ break;
+ }
+
+ if (!nitems) {
+ ret = 0;
+ goto out;
+ }
+
+ /*
+ * we need allocate some memory space, but it might cause the task
+ * to sleep, so we set all locked nodes in the path to blocking locks
+ * first.
+ */
+ btrfs_set_path_blocking(path);
+
+ keys = kmalloc_array(nitems, sizeof(struct btrfs_key), GFP_NOFS);
+ if (!keys) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ data_size = kmalloc_array(nitems, sizeof(u32), GFP_NOFS);
+ if (!data_size) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ /* get keys of all the delayed items */
+ i = 0;
+ list_for_each_entry(next, &head, tree_list) {
+ keys[i] = next->key;
+ data_size[i] = next->data_len;
+ i++;
+ }
+
+ /* reset all the locked nodes in the patch to spinning locks. */
+ btrfs_clear_path_blocking(path, NULL, 0);
+
+ /* insert the keys of the items */
+ setup_items_for_insert(root, path, keys, data_size,
+ total_data_size, total_size, nitems);
+
+ /* insert the dir index items */
+ slot = path->slots[0];
+ list_for_each_entry_safe(curr, next, &head, tree_list) {
+ data_ptr = btrfs_item_ptr(leaf, slot, char);
+ write_extent_buffer(leaf, &curr->data,
+ (unsigned long)data_ptr,
+ curr->data_len);
+ slot++;
+
+ btrfs_delayed_item_release_metadata(root, curr);
+
+ list_del(&curr->tree_list);
+ btrfs_release_delayed_item(curr);
+ }
+
+error:
+ kfree(data_size);
+ kfree(keys);
+out:
+ return ret;
+}
+
+/*
+ * This helper can just do simple insertion that needn't extend item for new
+ * data, such as directory name index insertion, inode insertion.
+ */
+static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_delayed_item *delayed_item)
+{
+ struct extent_buffer *leaf;
+ char *ptr;
+ int ret;
+
+ ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
+ delayed_item->data_len);
+ if (ret < 0 && ret != -EEXIST)
+ return ret;
+
+ leaf = path->nodes[0];
+
+ ptr = btrfs_item_ptr(leaf, path->slots[0], char);
+
+ write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
+ delayed_item->data_len);
+ btrfs_mark_buffer_dirty(leaf);
+
+ btrfs_delayed_item_release_metadata(root, delayed_item);
+ return 0;
+}
+
+/*
+ * we insert an item first, then if there are some continuous items, we try
+ * to insert those items into the same leaf.
+ */
+static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
+ struct btrfs_path *path,
+ struct btrfs_root *root,
+ struct btrfs_delayed_node *node)
+{
+ struct btrfs_delayed_item *curr, *prev;
+ int ret = 0;
+
+do_again:
+ mutex_lock(&node->mutex);
+ curr = __btrfs_first_delayed_insertion_item(node);
+ if (!curr)
+ goto insert_end;
+
+ ret = btrfs_insert_delayed_item(trans, root, path, curr);
+ if (ret < 0) {
+ btrfs_release_path(path);
+ goto insert_end;
+ }
+
+ prev = curr;
+ curr = __btrfs_next_delayed_item(prev);
+ if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
+ /* insert the continuous items into the same leaf */
+ path->slots[0]++;
+ btrfs_batch_insert_items(root, path, curr);
+ }
+ btrfs_release_delayed_item(prev);
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+
+ btrfs_release_path(path);
+ mutex_unlock(&node->mutex);
+ goto do_again;
+
+insert_end:
+ 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)
+{
+ struct btrfs_delayed_item *curr, *next;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+ struct list_head head;
+ int nitems, i, last_item;
+ int ret = 0;
+
+ BUG_ON(!path->nodes[0]);
+
+ leaf = path->nodes[0];
+
+ i = path->slots[0];
+ last_item = btrfs_header_nritems(leaf) - 1;
+ if (i > last_item)
+ return -ENOENT; /* FIXME: Is errno suitable? */
+
+ next = item;
+ INIT_LIST_HEAD(&head);
+ btrfs_item_key_to_cpu(leaf, &key, i);
+ nitems = 0;
+ /*
+ * count the number of the dir index items that we can delete in batch
+ */
+ while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
+ list_add_tail(&next->tree_list, &head);
+ nitems++;
+
+ curr = next;
+ next = __btrfs_next_delayed_item(curr);
+ if (!next)
+ break;
+
+ if (!btrfs_is_continuous_delayed_item(curr, next))
+ break;
+
+ i++;
+ if (i > last_item)
+ break;
+ btrfs_item_key_to_cpu(leaf, &key, i);
+ }
+
+ if (!nitems)
+ return 0;
+
+ ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
+ if (ret)
+ goto out;
+
+ list_for_each_entry_safe(curr, next, &head, tree_list) {
+ btrfs_delayed_item_release_metadata(root, curr);
+ list_del(&curr->tree_list);
+ btrfs_release_delayed_item(curr);
+ }
+
+out:
+ return ret;
+}
+
+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_delayed_item *curr, *prev;
+ int ret = 0;
+
+do_again:
+ mutex_lock(&node->mutex);
+ curr = __btrfs_first_delayed_deletion_item(node);
+ if (!curr)
+ goto delete_fail;
+
+ ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
+ if (ret < 0)
+ goto delete_fail;
+ else if (ret > 0) {
+ /*
+ * can't find the item which the node points to, so this node
+ * is invalid, just drop it.
+ */
+ prev = curr;
+ curr = __btrfs_next_delayed_item(prev);
+ btrfs_release_delayed_item(prev);
+ ret = 0;
+ btrfs_release_path(path);
+ if (curr) {
+ mutex_unlock(&node->mutex);
+ goto do_again;
+ } else
+ goto delete_fail;
+ }
+
+ btrfs_batch_delete_items(trans, root, path, curr);
+ btrfs_release_path(path);
+ mutex_unlock(&node->mutex);
+ goto do_again;
+
+delete_fail:
+ btrfs_release_path(path);
+ 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)
+{
+ struct btrfs_delayed_root *delayed_root;
+
+ ASSERT(delayed_node->root);
+ clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
+ 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_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) {
+ btrfs_release_path(path);
+ return -ENOENT;
+ } else if (ret < 0) {
+ return ret;
+ }
+
+ 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 no_iref;
+
+ 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);
+no_iref:
+ btrfs_release_path(path);
+err_out:
+ btrfs_delayed_inode_release_metadata(root, node);
+ btrfs_release_delayed_inode(node);
+
+ 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,
+ struct btrfs_root *root, int nr)
+{
+ 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)
+ return -EIO;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ path->leave_spinning = 1;
+
+ block_rsv = trans->block_rsv;
+ trans->block_rsv = &root->fs_info->delayed_block_rsv;
+
+ delayed_root = btrfs_get_delayed_root(root);
+
+ curr_node = btrfs_first_delayed_node(delayed_root);
+ while (curr_node && (!count || (count && nr--))) {
+ ret = __btrfs_commit_inode_delayed_items(trans, path,
+ curr_node);
+ if (ret) {
+ btrfs_release_delayed_node(curr_node);
+ curr_node = NULL;
+ btrfs_abort_transaction(trans, root, ret);
+ break;
+ }
+
+ prev_node = curr_node;
+ curr_node = btrfs_next_delayed_node(curr_node);
+ btrfs_release_delayed_node(prev_node);
+ }
+
+ if (curr_node)
+ btrfs_release_delayed_node(curr_node);
+ btrfs_free_path(path);
+ trans->block_rsv = block_rsv;
+
+ return ret;
+}
+
+int btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ return __btrfs_run_delayed_items(trans, root, -1);
+}
+
+int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, int nr)
+{
+ return __btrfs_run_delayed_items(trans, root, nr);
+}
+
+int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
+ struct 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;
+ }
+ path->leave_spinning = 1;
+
+ 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 inode *inode)
+{
+ 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;
+ }
+ path->leave_spinning = 1;
+
+ block_rsv = trans->block_rsv;
+ trans->block_rsv = &delayed_node->root->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, delayed_node->root);
+ btrfs_btree_balance_dirty(delayed_node->root);
+out:
+ btrfs_release_delayed_node(delayed_node);
+
+ return ret;
+}
+
+void btrfs_remove_delayed_node(struct inode *inode)
+{
+ struct btrfs_delayed_node *delayed_node;
+
+ delayed_node = ACCESS_ONCE(BTRFS_I(inode)->delayed_node);
+ if (!delayed_node)
+ return;
+
+ BTRFS_I(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;
+
+again:
+ if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND / 2)
+ goto free_path;
+
+ delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
+ if (!delayed_node)
+ goto free_path;
+
+ path->leave_spinning = 1;
+ root = delayed_node->root;
+
+ trans = btrfs_join_transaction(root);
+ if (IS_ERR(trans))
+ goto release_path;
+
+ 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, root);
+ btrfs_btree_balance_dirty_nodelay(root);
+
+release_path:
+ btrfs_release_path(path);
+ total_done++;
+
+ btrfs_release_prepared_delayed_node(delayed_node);
+ if (async_work->nr == 0 || total_done < async_work->nr)
+ goto again;
+
+free_path:
+ 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;
+
+ if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
+ return 0;
+
+ 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_delayed_meta_helper,
+ 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_root *root)
+{
+ struct btrfs_delayed_root *delayed_root;
+ delayed_root = btrfs_get_delayed_root(root);
+ WARN_ON(btrfs_first_delayed_node(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_root *root)
+{
+ struct btrfs_delayed_root *delayed_root;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+
+ delayed_root = btrfs_get_delayed_root(root);
+
+ if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
+ 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);
+}
+
+/* Will return 0 or -ENOMEM */
+int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, const char *name,
+ int name_len, struct inode *dir,
+ struct btrfs_disk_key *disk_key, u8 type,
+ u64 index)
+{
+ struct btrfs_delayed_node *delayed_node;
+ struct btrfs_delayed_item *delayed_item;
+ struct btrfs_dir_item *dir_item;
+ 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);
+ if (!delayed_item) {
+ ret = -ENOMEM;
+ goto release_node;
+ }
+
+ delayed_item->key.objectid = btrfs_ino(dir);
+ delayed_item->key.type = BTRFS_DIR_INDEX_KEY;
+ delayed_item->key.offset = 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);
+
+ ret = btrfs_delayed_item_reserve_metadata(trans, root, delayed_item);
+ /*
+ * we have reserved enough space when we start a new transaction,
+ * so reserving metadata failure is impossible
+ */
+ BUG_ON(ret);
+
+
+ mutex_lock(&delayed_node->mutex);
+ ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
+ if (unlikely(ret)) {
+ btrfs_err(root->fs_info, "err add delayed dir index item(name: %.*s) "
+ "into the insertion tree of the delayed node"
+ "(root id: %llu, inode id: %llu, errno: %d)",
+ name_len, name, delayed_node->root->objectid,
+ delayed_node->inode_id, ret);
+ BUG();
+ }
+ mutex_unlock(&delayed_node->mutex);
+
+release_node:
+ btrfs_release_delayed_node(delayed_node);
+ return ret;
+}
+
+static int btrfs_delete_delayed_insertion_item(struct btrfs_root *root,
+ struct btrfs_delayed_node *node,
+ struct btrfs_key *key)
+{
+ struct btrfs_delayed_item *item;
+
+ mutex_lock(&node->mutex);
+ item = __btrfs_lookup_delayed_insertion_item(node, key);
+ if (!item) {
+ mutex_unlock(&node->mutex);
+ return 1;
+ }
+
+ btrfs_delayed_item_release_metadata(root, item);
+ btrfs_release_delayed_item(item);
+ mutex_unlock(&node->mutex);
+ return 0;
+}
+
+int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct inode *dir,
+ u64 index)
+{
+ struct btrfs_delayed_node *node;
+ struct btrfs_delayed_item *item;
+ struct btrfs_key item_key;
+ int ret;
+
+ node = btrfs_get_or_create_delayed_node(dir);
+ if (IS_ERR(node))
+ return PTR_ERR(node);
+
+ item_key.objectid = btrfs_ino(dir);
+ item_key.type = BTRFS_DIR_INDEX_KEY;
+ item_key.offset = index;
+
+ ret = btrfs_delete_delayed_insertion_item(root, node, &item_key);
+ if (!ret)
+ goto end;
+
+ item = btrfs_alloc_delayed_item(0);
+ if (!item) {
+ ret = -ENOMEM;
+ goto end;
+ }
+
+ item->key = item_key;
+
+ ret = btrfs_delayed_item_reserve_metadata(trans, root, item);
+ /*
+ * we have reserved enough space when we start a new transaction,
+ * so reserving metadata failure is impossible.
+ */
+ BUG_ON(ret);
+
+ mutex_lock(&node->mutex);
+ ret = __btrfs_add_delayed_deletion_item(node, item);
+ if (unlikely(ret)) {
+ btrfs_err(root->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->objectid, node->inode_id,
+ ret);
+ BUG();
+ }
+ mutex_unlock(&node->mutex);
+end:
+ btrfs_release_delayed_node(node);
+ return ret;
+}
+
+int btrfs_inode_delayed_dir_index_count(struct 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;
+ }
+
+ BTRFS_I(inode)->index_cnt = delayed_node->index_cnt;
+ btrfs_release_delayed_node(delayed_node);
+ return 0;
+}
+
+void btrfs_get_delayed_items(struct inode *inode, 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(inode);
+ if (!delayed_node)
+ return;
+
+ mutex_lock(&delayed_node->mutex);
+ item = __btrfs_first_delayed_insertion_item(delayed_node);
+ while (item) {
+ atomic_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) {
+ atomic_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.
+ */
+ atomic_dec(&delayed_node->refs);
+}
+
+void btrfs_put_delayed_items(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 (atomic_dec_and_test(&curr->refs))
+ kfree(curr);
+ }
+
+ list_for_each_entry_safe(curr, next, del_list, readdir_list) {
+ list_del(&curr->readdir_list);
+ if (atomic_dec_and_test(&curr->refs))
+ kfree(curr);
+ }
+}
+
+int btrfs_should_delete_dir_index(struct list_head *del_list,
+ u64 index)
+{
+ struct btrfs_delayed_item *curr, *next;
+ int ret;
+
+ if (list_empty(del_list))
+ return 0;
+
+ list_for_each_entry_safe(curr, next, del_list, readdir_list) {
+ if (curr->key.offset > index)
+ break;
+
+ list_del(&curr->readdir_list);
+ ret = (curr->key.offset == index);
+
+ if (atomic_dec_and_test(&curr->refs))
+ kfree(curr);
+
+ if (ret)
+ return 1;
+ else
+ continue;
+ }
+ return 0;
+}
+
+/*
+ * 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->key.offset < ctx->pos) {
+ if (atomic_dec_and_test(&curr->refs))
+ kfree(curr);
+ continue;
+ }
+
+ ctx->pos = curr->key.offset;
+
+ di = (struct btrfs_dir_item *)curr->data;
+ name = (char *)(di + 1);
+ name_len = btrfs_stack_dir_name_len(di);
+
+ d_type = btrfs_filetype_table[di->type];
+ btrfs_disk_key_to_cpu(&location, &di->location);
+
+ over = !dir_emit(ctx, name, name_len,
+ location.objectid, d_type);
+
+ if (atomic_dec_and_test(&curr->refs))
+ kfree(curr);
+
+ if (over)
+ return 1;
+ }
+ return 0;
+}
+
+static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
+ struct btrfs_inode_item *inode_item,
+ struct inode *inode)
+{
+ 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->i_version);
+ btrfs_set_stack_inode_transid(inode_item, trans->transid);
+ btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
+ btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->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_delayed_node *delayed_node;
+ struct btrfs_inode_item *inode_item;
+
+ delayed_node = btrfs_get_delayed_node(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(inode, btrfs_stack_inode_size(inode_item));
+ 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->i_version = btrfs_stack_inode_sequence(inode_item);
+ inode->i_rdev = 0;
+ *rdev = btrfs_stack_inode_rdev(inode_item);
+ BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
+
+ 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 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);
+ goto release_node;
+ }
+
+ ret = btrfs_delayed_inode_reserve_metadata(trans, root, inode,
+ delayed_node);
+ if (ret)
+ goto release_node;
+
+ fill_stack_inode_item(trans, &delayed_node->inode_item, 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 inode *inode)
+{
+ 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 (BTRFS_I(inode)->root->fs_info->log_root_recovering)
+ 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(&BTRFS_I(inode)->root->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_delayed_item *curr_item, *prev_item;
+
+ mutex_lock(&delayed_node->mutex);
+ curr_item = __btrfs_first_delayed_insertion_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);
+ }
+
+ 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);
+ }
+
+ if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
+ btrfs_release_delayed_iref(delayed_node);
+
+ if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
+ btrfs_delayed_inode_release_metadata(root, delayed_node);
+ btrfs_release_delayed_inode(delayed_node);
+ }
+ mutex_unlock(&delayed_node->mutex);
+}
+
+void btrfs_kill_delayed_inode_items(struct 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++)
+ atomic_inc(&delayed_nodes[i]->refs);
+ spin_unlock(&root->inode_lock);
+
+ for (i = 0; i < n; i++) {
+ __btrfs_kill_delayed_node(delayed_nodes[i]);
+ btrfs_release_delayed_node(delayed_nodes[i]);
+ }
+ }
+}
+
+void btrfs_destroy_delayed_inodes(struct btrfs_root *root)
+{
+ struct btrfs_delayed_root *delayed_root;
+ struct btrfs_delayed_node *curr_node, *prev_node;
+
+ delayed_root = btrfs_get_delayed_root(root);
+
+ curr_node = btrfs_first_delayed_node(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);
+ }
+}
+