// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2011 Fujitsu. All rights reserved.
* Written by Miao Xie <[email protected]>
*/
#include <linux/slab.h>
#include <linux/iversion.h>
#include "ctree.h"
#include "fs.h"
#include "messages.h"
#include "misc.h"
#include "delayed-inode.h"
#include "disk-io.h"
#include "transaction.h"
#include "qgroup.h"
#include "locking.h"
#include "inode-item.h"
#include "space-info.h"
#include "accessors.h"
#include "file-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(btrfs_delayed_node, 0);
if (!delayed_node_cache)
return -ENOMEM;
return 0;
}
void __cold btrfs_delayed_inode_exit(void)
{
kmem_cache_destroy(delayed_node_cache);
}
void btrfs_init_delayed_root(struct btrfs_delayed_root *delayed_root)
{
atomic_set(&delayed_root->items, 0);
atomic_set(&delayed_root->items_seq, 0);
delayed_root->nodes = 0;
spin_lock_init(&delayed_root->lock);
init_waitqueue_head(&delayed_root->wait);
INIT_LIST_HEAD(&delayed_root->node_list);
INIT_LIST_HEAD(&delayed_root->prepare_list);
}
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;
}
xa_lock(&root->delayed_nodes);
node = xa_load(&root->delayed_nodes, ino);
if (node) {
if (btrfs_inode->delayed_node) {
refcount_inc(&node->refs); /* can be accessed */
BUG_ON(btrfs_inode->delayed_node != node);
xa_unlock(&root->delayed_nodes);
return node;
}
/*
* It's possible that we're racing into the middle of removing
* this node from the xarray. In this case, the refcount
* was zero and it should never go back to one. Just return
* NULL like it was never in the xarray 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 xarray, 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;
}
xa_unlock(&root->delayed_nodes);
return node;
}
xa_unlock(&root->delayed_nodes);
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;
void *ptr;
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 inode and can be accessed. */
refcount_set(&node->refs, 2);
/* Allocate and reserve the slot, from now it can return a NULL from xa_load(). */
ret = xa_reserve(&root->delayed_nodes, ino, GFP_NOFS);
if (ret == -ENOMEM) {
kmem_cache_free(delayed_node_cache, node);
return ERR_PTR(-ENOMEM);
}
xa_lock(&root->delayed_nodes);
ptr = xa_load(&root->delayed_nodes, ino);
if (ptr) {
/* Somebody inserted it, go back and read it. */
xa_unlock(&root->delayed_nodes);
kmem_cache_free(delayed_node_cache, node);
node = NULL;
goto again;
}
ptr = __xa_store(&root->delayed_nodes, ino, node, GFP_ATOMIC);
ASSERT(xa_err(ptr) != -EINVAL);
ASSERT(xa_err(ptr) != -ENOMEM);
ASSERT(ptr == NULL);
btrfs_inode->delayed_node = node;
xa_unlock(&root->delayed_nodes);
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;
xa_erase(&root->delayed_nodes, delayed_node->inode_id);
/*
* 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);
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(struct_size(item, data, 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;
}
/*
* 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;
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 curr_index_batch_size and index_item_leaves fields.
*/
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)) {
ASSERT(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(trans, leaf);
if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
goto out;
/*
* Now we're going to delete the INODE_REF/EXTREF, which should be the
* only one ref left. Check if the next item is an INODE_REF/EXTREF.
*
* But if we're the last item already, release and search for the last
* INODE_REF/EXTREF.
*/
if (path->slots[0] + 1 >= btrfs_header_nritems(leaf)) {
key.objectid = node->inode_id;
key.type = BTRFS_INODE_EXTREF_KEY;
key.offset = (u64)-1;
btrfs_release_path(path);
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret < 0)
goto err_out;
ASSERT(ret > 0);
ASSERT(path->slots[0] > 0);
ret = 0;
path->slots[0]--;
leaf = path->nodes[0];
} else {
path->slots[0]++;
}
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.
*/
ret = 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;
}
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_record_root_in_trans(trans, node->root);
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);
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,
const struct btrfs_disk_key *disk_key, u8 flags,
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_flags(dir_item, flags);
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, btrfs_root_id(node->root),
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 btrfs_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(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 btrfs_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->vfs_inode.i_rwsem);
}
int btrfs_should_delete_dir_index(const 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;
}
/*
* Read dir info stored in the delayed tree.
*/
int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
const 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;
/*
* 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(btrfs_dir_flags_to_ftype(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_get_atime_sec(inode));
btrfs_set_stack_timespec_nsec(&inode_item->atime,
inode_get_atime_nsec(inode));
btrfs_set_stack_timespec_sec(&inode_item->mtime,
inode_get_mtime_sec(inode));
btrfs_set_stack_timespec_nsec(&inode_item->mtime,
inode_get_mtime_nsec(inode));
btrfs_set_stack_timespec_sec(&inode_item->ctime,
inode_get_ctime_sec(inode));
btrfs_set_stack_timespec_nsec(&inode_item->ctime,
inode_get_ctime_nsec(inode));
btrfs_set_stack_timespec_sec(&inode_item->otime, BTRFS_I(inode)->i_otime_sec);
btrfs_set_stack_timespec_nsec(&inode_item->otime, BTRFS_I(inode)->i_otime_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_set_atime(inode, btrfs_stack_timespec_sec(&inode_item->atime),
btrfs_stack_timespec_nsec(&inode_item->atime));
inode_set_mtime(inode, btrfs_stack_timespec_sec(&inode_item->mtime),
btrfs_stack_timespec_nsec(&inode_item->mtime));
inode_set_ctime(inode, btrfs_stack_timespec_sec(&inode_item->ctime),
btrfs_stack_timespec_nsec(&inode_item->ctime));
BTRFS_I(inode)->i_otime_sec = btrfs_stack_timespec_sec(&inode_item->otime);
BTRFS_I(inode)->i_otime_nsec = btrfs_stack_timespec_nsec(&inode_item->otime);
inode->i_generation = BTRFS_I(inode)->generation;
if (S_ISDIR(inode->i_mode))
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_inode *inode)
{
struct btrfs_root *root = inode->root;
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)
{
unsigned long index = 0;
struct btrfs_delayed_node *delayed_nodes[8];
while (1) {
struct btrfs_delayed_node *node;
int count;
xa_lock(&root->delayed_nodes);
if (xa_empty(&root->delayed_nodes)) {
xa_unlock(&root->delayed_nodes);
return;
}
count = 0;
xa_for_each_start(&root->delayed_nodes, index, node, index) {
/*
* 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(&node->refs)) {
delayed_nodes[count] = node;
count++;
}
if (count >= ARRAY_SIZE(delayed_nodes))
break;
}
xa_unlock(&root->delayed_nodes);
index++;
for (int i = 0; i < count; i++) {
__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);
}
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