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4274 lines
113 KiB
4274 lines
113 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Copyright (C) 2008 Red Hat. All rights reserved. |
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*/ |
|
|
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#include <linux/pagemap.h> |
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#include <linux/sched.h> |
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#include <linux/sched/signal.h> |
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#include <linux/slab.h> |
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#include <linux/math64.h> |
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#include <linux/ratelimit.h> |
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#include <linux/error-injection.h> |
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#include <linux/sched/mm.h> |
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#include "misc.h" |
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#include "ctree.h" |
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#include "free-space-cache.h" |
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#include "transaction.h" |
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#include "disk-io.h" |
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#include "extent_io.h" |
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#include "volumes.h" |
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#include "space-info.h" |
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#include "delalloc-space.h" |
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#include "block-group.h" |
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#include "discard.h" |
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#include "subpage.h" |
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#include "inode-item.h" |
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|
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#define BITS_PER_BITMAP (PAGE_SIZE * 8UL) |
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#define MAX_CACHE_BYTES_PER_GIG SZ_64K |
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#define FORCE_EXTENT_THRESHOLD SZ_1M |
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|
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struct btrfs_trim_range { |
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u64 start; |
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u64 bytes; |
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struct list_head list; |
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}; |
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|
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static int link_free_space(struct btrfs_free_space_ctl *ctl, |
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struct btrfs_free_space *info); |
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static void unlink_free_space(struct btrfs_free_space_ctl *ctl, |
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struct btrfs_free_space *info, bool update_stat); |
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static int search_bitmap(struct btrfs_free_space_ctl *ctl, |
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struct btrfs_free_space *bitmap_info, u64 *offset, |
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u64 *bytes, bool for_alloc); |
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static void free_bitmap(struct btrfs_free_space_ctl *ctl, |
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struct btrfs_free_space *bitmap_info); |
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static void bitmap_clear_bits(struct btrfs_free_space_ctl *ctl, |
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struct btrfs_free_space *info, u64 offset, |
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u64 bytes, bool update_stats); |
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|
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static struct inode *__lookup_free_space_inode(struct btrfs_root *root, |
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struct btrfs_path *path, |
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u64 offset) |
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{ |
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struct btrfs_fs_info *fs_info = root->fs_info; |
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struct btrfs_key key; |
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struct btrfs_key location; |
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struct btrfs_disk_key disk_key; |
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struct btrfs_free_space_header *header; |
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struct extent_buffer *leaf; |
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struct inode *inode = NULL; |
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unsigned nofs_flag; |
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int ret; |
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|
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key.objectid = BTRFS_FREE_SPACE_OBJECTID; |
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key.offset = offset; |
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key.type = 0; |
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|
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ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
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if (ret < 0) |
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return ERR_PTR(ret); |
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if (ret > 0) { |
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btrfs_release_path(path); |
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return ERR_PTR(-ENOENT); |
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} |
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|
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leaf = path->nodes[0]; |
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header = btrfs_item_ptr(leaf, path->slots[0], |
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struct btrfs_free_space_header); |
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btrfs_free_space_key(leaf, header, &disk_key); |
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btrfs_disk_key_to_cpu(&location, &disk_key); |
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btrfs_release_path(path); |
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|
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/* |
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* We are often under a trans handle at this point, so we need to make |
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* sure NOFS is set to keep us from deadlocking. |
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*/ |
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nofs_flag = memalloc_nofs_save(); |
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inode = btrfs_iget_path(fs_info->sb, location.objectid, root, path); |
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btrfs_release_path(path); |
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memalloc_nofs_restore(nofs_flag); |
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if (IS_ERR(inode)) |
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return inode; |
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|
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mapping_set_gfp_mask(inode->i_mapping, |
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mapping_gfp_constraint(inode->i_mapping, |
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~(__GFP_FS | __GFP_HIGHMEM))); |
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|
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return inode; |
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} |
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|
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struct inode *lookup_free_space_inode(struct btrfs_block_group *block_group, |
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struct btrfs_path *path) |
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{ |
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struct btrfs_fs_info *fs_info = block_group->fs_info; |
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struct inode *inode = NULL; |
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u32 flags = BTRFS_INODE_NODATASUM | BTRFS_INODE_NODATACOW; |
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|
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spin_lock(&block_group->lock); |
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if (block_group->inode) |
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inode = igrab(block_group->inode); |
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spin_unlock(&block_group->lock); |
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if (inode) |
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return inode; |
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|
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inode = __lookup_free_space_inode(fs_info->tree_root, path, |
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block_group->start); |
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if (IS_ERR(inode)) |
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return inode; |
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|
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spin_lock(&block_group->lock); |
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if (!((BTRFS_I(inode)->flags & flags) == flags)) { |
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btrfs_info(fs_info, "Old style space inode found, converting."); |
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BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM | |
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BTRFS_INODE_NODATACOW; |
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block_group->disk_cache_state = BTRFS_DC_CLEAR; |
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} |
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|
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if (!block_group->iref) { |
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block_group->inode = igrab(inode); |
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block_group->iref = 1; |
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} |
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spin_unlock(&block_group->lock); |
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|
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return inode; |
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} |
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|
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static int __create_free_space_inode(struct btrfs_root *root, |
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struct btrfs_trans_handle *trans, |
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struct btrfs_path *path, |
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u64 ino, u64 offset) |
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{ |
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struct btrfs_key key; |
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struct btrfs_disk_key disk_key; |
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struct btrfs_free_space_header *header; |
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struct btrfs_inode_item *inode_item; |
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struct extent_buffer *leaf; |
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/* We inline CRCs for the free disk space cache */ |
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const u64 flags = BTRFS_INODE_NOCOMPRESS | BTRFS_INODE_PREALLOC | |
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BTRFS_INODE_NODATASUM | BTRFS_INODE_NODATACOW; |
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int ret; |
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|
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ret = btrfs_insert_empty_inode(trans, root, path, ino); |
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if (ret) |
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return ret; |
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|
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leaf = path->nodes[0]; |
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inode_item = btrfs_item_ptr(leaf, path->slots[0], |
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struct btrfs_inode_item); |
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btrfs_item_key(leaf, &disk_key, path->slots[0]); |
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memzero_extent_buffer(leaf, (unsigned long)inode_item, |
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sizeof(*inode_item)); |
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btrfs_set_inode_generation(leaf, inode_item, trans->transid); |
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btrfs_set_inode_size(leaf, inode_item, 0); |
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btrfs_set_inode_nbytes(leaf, inode_item, 0); |
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btrfs_set_inode_uid(leaf, inode_item, 0); |
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btrfs_set_inode_gid(leaf, inode_item, 0); |
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btrfs_set_inode_mode(leaf, inode_item, S_IFREG | 0600); |
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btrfs_set_inode_flags(leaf, inode_item, flags); |
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btrfs_set_inode_nlink(leaf, inode_item, 1); |
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btrfs_set_inode_transid(leaf, inode_item, trans->transid); |
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btrfs_set_inode_block_group(leaf, inode_item, offset); |
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btrfs_mark_buffer_dirty(leaf); |
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btrfs_release_path(path); |
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|
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key.objectid = BTRFS_FREE_SPACE_OBJECTID; |
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key.offset = offset; |
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key.type = 0; |
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ret = btrfs_insert_empty_item(trans, root, path, &key, |
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sizeof(struct btrfs_free_space_header)); |
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if (ret < 0) { |
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btrfs_release_path(path); |
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return ret; |
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} |
|
|
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leaf = path->nodes[0]; |
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header = btrfs_item_ptr(leaf, path->slots[0], |
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struct btrfs_free_space_header); |
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memzero_extent_buffer(leaf, (unsigned long)header, sizeof(*header)); |
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btrfs_set_free_space_key(leaf, header, &disk_key); |
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btrfs_mark_buffer_dirty(leaf); |
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btrfs_release_path(path); |
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|
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return 0; |
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} |
|
|
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int create_free_space_inode(struct btrfs_trans_handle *trans, |
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struct btrfs_block_group *block_group, |
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struct btrfs_path *path) |
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{ |
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int ret; |
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u64 ino; |
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|
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ret = btrfs_get_free_objectid(trans->fs_info->tree_root, &ino); |
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if (ret < 0) |
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return ret; |
|
|
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return __create_free_space_inode(trans->fs_info->tree_root, trans, path, |
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ino, block_group->start); |
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} |
|
|
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/* |
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* inode is an optional sink: if it is NULL, btrfs_remove_free_space_inode |
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* handles lookup, otherwise it takes ownership and iputs the inode. |
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* Don't reuse an inode pointer after passing it into this function. |
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*/ |
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int btrfs_remove_free_space_inode(struct btrfs_trans_handle *trans, |
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struct inode *inode, |
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struct btrfs_block_group *block_group) |
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{ |
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struct btrfs_path *path; |
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struct btrfs_key key; |
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int ret = 0; |
|
|
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path = btrfs_alloc_path(); |
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if (!path) |
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return -ENOMEM; |
|
|
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if (!inode) |
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inode = lookup_free_space_inode(block_group, path); |
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if (IS_ERR(inode)) { |
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if (PTR_ERR(inode) != -ENOENT) |
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ret = PTR_ERR(inode); |
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goto out; |
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} |
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ret = btrfs_orphan_add(trans, BTRFS_I(inode)); |
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if (ret) { |
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btrfs_add_delayed_iput(inode); |
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goto out; |
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} |
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clear_nlink(inode); |
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/* One for the block groups ref */ |
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spin_lock(&block_group->lock); |
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if (block_group->iref) { |
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block_group->iref = 0; |
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block_group->inode = NULL; |
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spin_unlock(&block_group->lock); |
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iput(inode); |
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} else { |
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spin_unlock(&block_group->lock); |
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} |
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/* One for the lookup ref */ |
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btrfs_add_delayed_iput(inode); |
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|
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key.objectid = BTRFS_FREE_SPACE_OBJECTID; |
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key.type = 0; |
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key.offset = block_group->start; |
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ret = btrfs_search_slot(trans, trans->fs_info->tree_root, &key, path, |
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-1, 1); |
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if (ret) { |
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if (ret > 0) |
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ret = 0; |
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goto out; |
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} |
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ret = btrfs_del_item(trans, trans->fs_info->tree_root, path); |
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out: |
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btrfs_free_path(path); |
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return ret; |
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} |
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|
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int btrfs_check_trunc_cache_free_space(struct btrfs_fs_info *fs_info, |
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struct btrfs_block_rsv *rsv) |
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{ |
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u64 needed_bytes; |
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int ret; |
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|
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/* 1 for slack space, 1 for updating the inode */ |
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needed_bytes = btrfs_calc_insert_metadata_size(fs_info, 1) + |
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btrfs_calc_metadata_size(fs_info, 1); |
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|
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spin_lock(&rsv->lock); |
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if (rsv->reserved < needed_bytes) |
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ret = -ENOSPC; |
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else |
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ret = 0; |
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spin_unlock(&rsv->lock); |
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return ret; |
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} |
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|
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int btrfs_truncate_free_space_cache(struct btrfs_trans_handle *trans, |
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struct btrfs_block_group *block_group, |
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struct inode *vfs_inode) |
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{ |
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struct btrfs_truncate_control control = { |
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.inode = BTRFS_I(vfs_inode), |
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.new_size = 0, |
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.ino = btrfs_ino(BTRFS_I(vfs_inode)), |
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.min_type = BTRFS_EXTENT_DATA_KEY, |
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.clear_extent_range = true, |
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}; |
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struct btrfs_inode *inode = BTRFS_I(vfs_inode); |
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struct btrfs_root *root = inode->root; |
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struct extent_state *cached_state = NULL; |
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int ret = 0; |
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bool locked = false; |
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|
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if (block_group) { |
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struct btrfs_path *path = btrfs_alloc_path(); |
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|
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if (!path) { |
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ret = -ENOMEM; |
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goto fail; |
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} |
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locked = true; |
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mutex_lock(&trans->transaction->cache_write_mutex); |
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if (!list_empty(&block_group->io_list)) { |
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list_del_init(&block_group->io_list); |
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|
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btrfs_wait_cache_io(trans, block_group, path); |
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btrfs_put_block_group(block_group); |
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} |
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|
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/* |
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* now that we've truncated the cache away, its no longer |
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* setup or written |
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*/ |
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spin_lock(&block_group->lock); |
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block_group->disk_cache_state = BTRFS_DC_CLEAR; |
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spin_unlock(&block_group->lock); |
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btrfs_free_path(path); |
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} |
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|
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btrfs_i_size_write(inode, 0); |
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truncate_pagecache(vfs_inode, 0); |
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|
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lock_extent_bits(&inode->io_tree, 0, (u64)-1, &cached_state); |
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btrfs_drop_extent_cache(inode, 0, (u64)-1, 0); |
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|
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/* |
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* We skip the throttling logic for free space cache inodes, so we don't |
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* need to check for -EAGAIN. |
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*/ |
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ret = btrfs_truncate_inode_items(trans, root, &control); |
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|
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inode_sub_bytes(&inode->vfs_inode, control.sub_bytes); |
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btrfs_inode_safe_disk_i_size_write(inode, control.last_size); |
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|
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unlock_extent_cached(&inode->io_tree, 0, (u64)-1, &cached_state); |
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if (ret) |
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goto fail; |
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|
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ret = btrfs_update_inode(trans, root, inode); |
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|
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fail: |
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if (locked) |
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mutex_unlock(&trans->transaction->cache_write_mutex); |
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if (ret) |
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btrfs_abort_transaction(trans, ret); |
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|
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return ret; |
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} |
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|
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static void readahead_cache(struct inode *inode) |
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{ |
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struct file_ra_state ra; |
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unsigned long last_index; |
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|
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file_ra_state_init(&ra, inode->i_mapping); |
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last_index = (i_size_read(inode) - 1) >> PAGE_SHIFT; |
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|
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page_cache_sync_readahead(inode->i_mapping, &ra, NULL, 0, last_index); |
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} |
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|
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static int io_ctl_init(struct btrfs_io_ctl *io_ctl, struct inode *inode, |
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int write) |
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{ |
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int num_pages; |
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|
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num_pages = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); |
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|
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/* Make sure we can fit our crcs and generation into the first page */ |
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if (write && (num_pages * sizeof(u32) + sizeof(u64)) > PAGE_SIZE) |
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return -ENOSPC; |
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|
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memset(io_ctl, 0, sizeof(struct btrfs_io_ctl)); |
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|
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io_ctl->pages = kcalloc(num_pages, sizeof(struct page *), GFP_NOFS); |
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if (!io_ctl->pages) |
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return -ENOMEM; |
|
|
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io_ctl->num_pages = num_pages; |
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io_ctl->fs_info = btrfs_sb(inode->i_sb); |
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io_ctl->inode = inode; |
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|
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return 0; |
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} |
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ALLOW_ERROR_INJECTION(io_ctl_init, ERRNO); |
|
|
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static void io_ctl_free(struct btrfs_io_ctl *io_ctl) |
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{ |
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kfree(io_ctl->pages); |
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io_ctl->pages = NULL; |
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} |
|
|
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static void io_ctl_unmap_page(struct btrfs_io_ctl *io_ctl) |
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{ |
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if (io_ctl->cur) { |
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io_ctl->cur = NULL; |
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io_ctl->orig = NULL; |
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} |
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} |
|
|
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static void io_ctl_map_page(struct btrfs_io_ctl *io_ctl, int clear) |
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{ |
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ASSERT(io_ctl->index < io_ctl->num_pages); |
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io_ctl->page = io_ctl->pages[io_ctl->index++]; |
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io_ctl->cur = page_address(io_ctl->page); |
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io_ctl->orig = io_ctl->cur; |
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io_ctl->size = PAGE_SIZE; |
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if (clear) |
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clear_page(io_ctl->cur); |
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} |
|
|
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static void io_ctl_drop_pages(struct btrfs_io_ctl *io_ctl) |
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{ |
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int i; |
|
|
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io_ctl_unmap_page(io_ctl); |
|
|
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for (i = 0; i < io_ctl->num_pages; i++) { |
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if (io_ctl->pages[i]) { |
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btrfs_page_clear_checked(io_ctl->fs_info, |
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io_ctl->pages[i], |
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page_offset(io_ctl->pages[i]), |
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PAGE_SIZE); |
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unlock_page(io_ctl->pages[i]); |
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put_page(io_ctl->pages[i]); |
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} |
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} |
|
} |
|
|
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static int io_ctl_prepare_pages(struct btrfs_io_ctl *io_ctl, bool uptodate) |
|
{ |
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struct page *page; |
|
struct inode *inode = io_ctl->inode; |
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gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); |
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int i; |
|
|
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for (i = 0; i < io_ctl->num_pages; i++) { |
|
int ret; |
|
|
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page = find_or_create_page(inode->i_mapping, i, mask); |
|
if (!page) { |
|
io_ctl_drop_pages(io_ctl); |
|
return -ENOMEM; |
|
} |
|
|
|
ret = set_page_extent_mapped(page); |
|
if (ret < 0) { |
|
unlock_page(page); |
|
put_page(page); |
|
io_ctl_drop_pages(io_ctl); |
|
return ret; |
|
} |
|
|
|
io_ctl->pages[i] = page; |
|
if (uptodate && !PageUptodate(page)) { |
|
btrfs_readpage(NULL, page); |
|
lock_page(page); |
|
if (page->mapping != inode->i_mapping) { |
|
btrfs_err(BTRFS_I(inode)->root->fs_info, |
|
"free space cache page truncated"); |
|
io_ctl_drop_pages(io_ctl); |
|
return -EIO; |
|
} |
|
if (!PageUptodate(page)) { |
|
btrfs_err(BTRFS_I(inode)->root->fs_info, |
|
"error reading free space cache"); |
|
io_ctl_drop_pages(io_ctl); |
|
return -EIO; |
|
} |
|
} |
|
} |
|
|
|
for (i = 0; i < io_ctl->num_pages; i++) |
|
clear_page_dirty_for_io(io_ctl->pages[i]); |
|
|
|
return 0; |
|
} |
|
|
|
static void io_ctl_set_generation(struct btrfs_io_ctl *io_ctl, u64 generation) |
|
{ |
|
io_ctl_map_page(io_ctl, 1); |
|
|
|
/* |
|
* Skip the csum areas. If we don't check crcs then we just have a |
|
* 64bit chunk at the front of the first page. |
|
*/ |
|
io_ctl->cur += (sizeof(u32) * io_ctl->num_pages); |
|
io_ctl->size -= sizeof(u64) + (sizeof(u32) * io_ctl->num_pages); |
|
|
|
put_unaligned_le64(generation, io_ctl->cur); |
|
io_ctl->cur += sizeof(u64); |
|
} |
|
|
|
static int io_ctl_check_generation(struct btrfs_io_ctl *io_ctl, u64 generation) |
|
{ |
|
u64 cache_gen; |
|
|
|
/* |
|
* Skip the crc area. If we don't check crcs then we just have a 64bit |
|
* chunk at the front of the first page. |
|
*/ |
|
io_ctl->cur += sizeof(u32) * io_ctl->num_pages; |
|
io_ctl->size -= sizeof(u64) + (sizeof(u32) * io_ctl->num_pages); |
|
|
|
cache_gen = get_unaligned_le64(io_ctl->cur); |
|
if (cache_gen != generation) { |
|
btrfs_err_rl(io_ctl->fs_info, |
|
"space cache generation (%llu) does not match inode (%llu)", |
|
cache_gen, generation); |
|
io_ctl_unmap_page(io_ctl); |
|
return -EIO; |
|
} |
|
io_ctl->cur += sizeof(u64); |
|
return 0; |
|
} |
|
|
|
static void io_ctl_set_crc(struct btrfs_io_ctl *io_ctl, int index) |
|
{ |
|
u32 *tmp; |
|
u32 crc = ~(u32)0; |
|
unsigned offset = 0; |
|
|
|
if (index == 0) |
|
offset = sizeof(u32) * io_ctl->num_pages; |
|
|
|
crc = btrfs_crc32c(crc, io_ctl->orig + offset, PAGE_SIZE - offset); |
|
btrfs_crc32c_final(crc, (u8 *)&crc); |
|
io_ctl_unmap_page(io_ctl); |
|
tmp = page_address(io_ctl->pages[0]); |
|
tmp += index; |
|
*tmp = crc; |
|
} |
|
|
|
static int io_ctl_check_crc(struct btrfs_io_ctl *io_ctl, int index) |
|
{ |
|
u32 *tmp, val; |
|
u32 crc = ~(u32)0; |
|
unsigned offset = 0; |
|
|
|
if (index == 0) |
|
offset = sizeof(u32) * io_ctl->num_pages; |
|
|
|
tmp = page_address(io_ctl->pages[0]); |
|
tmp += index; |
|
val = *tmp; |
|
|
|
io_ctl_map_page(io_ctl, 0); |
|
crc = btrfs_crc32c(crc, io_ctl->orig + offset, PAGE_SIZE - offset); |
|
btrfs_crc32c_final(crc, (u8 *)&crc); |
|
if (val != crc) { |
|
btrfs_err_rl(io_ctl->fs_info, |
|
"csum mismatch on free space cache"); |
|
io_ctl_unmap_page(io_ctl); |
|
return -EIO; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int io_ctl_add_entry(struct btrfs_io_ctl *io_ctl, u64 offset, u64 bytes, |
|
void *bitmap) |
|
{ |
|
struct btrfs_free_space_entry *entry; |
|
|
|
if (!io_ctl->cur) |
|
return -ENOSPC; |
|
|
|
entry = io_ctl->cur; |
|
put_unaligned_le64(offset, &entry->offset); |
|
put_unaligned_le64(bytes, &entry->bytes); |
|
entry->type = (bitmap) ? BTRFS_FREE_SPACE_BITMAP : |
|
BTRFS_FREE_SPACE_EXTENT; |
|
io_ctl->cur += sizeof(struct btrfs_free_space_entry); |
|
io_ctl->size -= sizeof(struct btrfs_free_space_entry); |
|
|
|
if (io_ctl->size >= sizeof(struct btrfs_free_space_entry)) |
|
return 0; |
|
|
|
io_ctl_set_crc(io_ctl, io_ctl->index - 1); |
|
|
|
/* No more pages to map */ |
|
if (io_ctl->index >= io_ctl->num_pages) |
|
return 0; |
|
|
|
/* map the next page */ |
|
io_ctl_map_page(io_ctl, 1); |
|
return 0; |
|
} |
|
|
|
static int io_ctl_add_bitmap(struct btrfs_io_ctl *io_ctl, void *bitmap) |
|
{ |
|
if (!io_ctl->cur) |
|
return -ENOSPC; |
|
|
|
/* |
|
* If we aren't at the start of the current page, unmap this one and |
|
* map the next one if there is any left. |
|
*/ |
|
if (io_ctl->cur != io_ctl->orig) { |
|
io_ctl_set_crc(io_ctl, io_ctl->index - 1); |
|
if (io_ctl->index >= io_ctl->num_pages) |
|
return -ENOSPC; |
|
io_ctl_map_page(io_ctl, 0); |
|
} |
|
|
|
copy_page(io_ctl->cur, bitmap); |
|
io_ctl_set_crc(io_ctl, io_ctl->index - 1); |
|
if (io_ctl->index < io_ctl->num_pages) |
|
io_ctl_map_page(io_ctl, 0); |
|
return 0; |
|
} |
|
|
|
static void io_ctl_zero_remaining_pages(struct btrfs_io_ctl *io_ctl) |
|
{ |
|
/* |
|
* If we're not on the boundary we know we've modified the page and we |
|
* need to crc the page. |
|
*/ |
|
if (io_ctl->cur != io_ctl->orig) |
|
io_ctl_set_crc(io_ctl, io_ctl->index - 1); |
|
else |
|
io_ctl_unmap_page(io_ctl); |
|
|
|
while (io_ctl->index < io_ctl->num_pages) { |
|
io_ctl_map_page(io_ctl, 1); |
|
io_ctl_set_crc(io_ctl, io_ctl->index - 1); |
|
} |
|
} |
|
|
|
static int io_ctl_read_entry(struct btrfs_io_ctl *io_ctl, |
|
struct btrfs_free_space *entry, u8 *type) |
|
{ |
|
struct btrfs_free_space_entry *e; |
|
int ret; |
|
|
|
if (!io_ctl->cur) { |
|
ret = io_ctl_check_crc(io_ctl, io_ctl->index); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
e = io_ctl->cur; |
|
entry->offset = get_unaligned_le64(&e->offset); |
|
entry->bytes = get_unaligned_le64(&e->bytes); |
|
*type = e->type; |
|
io_ctl->cur += sizeof(struct btrfs_free_space_entry); |
|
io_ctl->size -= sizeof(struct btrfs_free_space_entry); |
|
|
|
if (io_ctl->size >= sizeof(struct btrfs_free_space_entry)) |
|
return 0; |
|
|
|
io_ctl_unmap_page(io_ctl); |
|
|
|
return 0; |
|
} |
|
|
|
static int io_ctl_read_bitmap(struct btrfs_io_ctl *io_ctl, |
|
struct btrfs_free_space *entry) |
|
{ |
|
int ret; |
|
|
|
ret = io_ctl_check_crc(io_ctl, io_ctl->index); |
|
if (ret) |
|
return ret; |
|
|
|
copy_page(entry->bitmap, io_ctl->cur); |
|
io_ctl_unmap_page(io_ctl); |
|
|
|
return 0; |
|
} |
|
|
|
static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl) |
|
{ |
|
struct btrfs_block_group *block_group = ctl->block_group; |
|
u64 max_bytes; |
|
u64 bitmap_bytes; |
|
u64 extent_bytes; |
|
u64 size = block_group->length; |
|
u64 bytes_per_bg = BITS_PER_BITMAP * ctl->unit; |
|
u64 max_bitmaps = div64_u64(size + bytes_per_bg - 1, bytes_per_bg); |
|
|
|
max_bitmaps = max_t(u64, max_bitmaps, 1); |
|
|
|
ASSERT(ctl->total_bitmaps <= max_bitmaps); |
|
|
|
/* |
|
* We are trying to keep the total amount of memory used per 1GiB of |
|
* space to be MAX_CACHE_BYTES_PER_GIG. However, with a reclamation |
|
* mechanism of pulling extents >= FORCE_EXTENT_THRESHOLD out of |
|
* bitmaps, we may end up using more memory than this. |
|
*/ |
|
if (size < SZ_1G) |
|
max_bytes = MAX_CACHE_BYTES_PER_GIG; |
|
else |
|
max_bytes = MAX_CACHE_BYTES_PER_GIG * div_u64(size, SZ_1G); |
|
|
|
bitmap_bytes = ctl->total_bitmaps * ctl->unit; |
|
|
|
/* |
|
* we want the extent entry threshold to always be at most 1/2 the max |
|
* bytes we can have, or whatever is less than that. |
|
*/ |
|
extent_bytes = max_bytes - bitmap_bytes; |
|
extent_bytes = min_t(u64, extent_bytes, max_bytes >> 1); |
|
|
|
ctl->extents_thresh = |
|
div_u64(extent_bytes, sizeof(struct btrfs_free_space)); |
|
} |
|
|
|
static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode, |
|
struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_path *path, u64 offset) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct btrfs_free_space_header *header; |
|
struct extent_buffer *leaf; |
|
struct btrfs_io_ctl io_ctl; |
|
struct btrfs_key key; |
|
struct btrfs_free_space *e, *n; |
|
LIST_HEAD(bitmaps); |
|
u64 num_entries; |
|
u64 num_bitmaps; |
|
u64 generation; |
|
u8 type; |
|
int ret = 0; |
|
|
|
/* Nothing in the space cache, goodbye */ |
|
if (!i_size_read(inode)) |
|
return 0; |
|
|
|
key.objectid = BTRFS_FREE_SPACE_OBJECTID; |
|
key.offset = offset; |
|
key.type = 0; |
|
|
|
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
|
if (ret < 0) |
|
return 0; |
|
else if (ret > 0) { |
|
btrfs_release_path(path); |
|
return 0; |
|
} |
|
|
|
ret = -1; |
|
|
|
leaf = path->nodes[0]; |
|
header = btrfs_item_ptr(leaf, path->slots[0], |
|
struct btrfs_free_space_header); |
|
num_entries = btrfs_free_space_entries(leaf, header); |
|
num_bitmaps = btrfs_free_space_bitmaps(leaf, header); |
|
generation = btrfs_free_space_generation(leaf, header); |
|
btrfs_release_path(path); |
|
|
|
if (!BTRFS_I(inode)->generation) { |
|
btrfs_info(fs_info, |
|
"the free space cache file (%llu) is invalid, skip it", |
|
offset); |
|
return 0; |
|
} |
|
|
|
if (BTRFS_I(inode)->generation != generation) { |
|
btrfs_err(fs_info, |
|
"free space inode generation (%llu) did not match free space cache generation (%llu)", |
|
BTRFS_I(inode)->generation, generation); |
|
return 0; |
|
} |
|
|
|
if (!num_entries) |
|
return 0; |
|
|
|
ret = io_ctl_init(&io_ctl, inode, 0); |
|
if (ret) |
|
return ret; |
|
|
|
readahead_cache(inode); |
|
|
|
ret = io_ctl_prepare_pages(&io_ctl, true); |
|
if (ret) |
|
goto out; |
|
|
|
ret = io_ctl_check_crc(&io_ctl, 0); |
|
if (ret) |
|
goto free_cache; |
|
|
|
ret = io_ctl_check_generation(&io_ctl, generation); |
|
if (ret) |
|
goto free_cache; |
|
|
|
while (num_entries) { |
|
e = kmem_cache_zalloc(btrfs_free_space_cachep, |
|
GFP_NOFS); |
|
if (!e) { |
|
ret = -ENOMEM; |
|
goto free_cache; |
|
} |
|
|
|
ret = io_ctl_read_entry(&io_ctl, e, &type); |
|
if (ret) { |
|
kmem_cache_free(btrfs_free_space_cachep, e); |
|
goto free_cache; |
|
} |
|
|
|
if (!e->bytes) { |
|
ret = -1; |
|
kmem_cache_free(btrfs_free_space_cachep, e); |
|
goto free_cache; |
|
} |
|
|
|
if (type == BTRFS_FREE_SPACE_EXTENT) { |
|
spin_lock(&ctl->tree_lock); |
|
ret = link_free_space(ctl, e); |
|
spin_unlock(&ctl->tree_lock); |
|
if (ret) { |
|
btrfs_err(fs_info, |
|
"Duplicate entries in free space cache, dumping"); |
|
kmem_cache_free(btrfs_free_space_cachep, e); |
|
goto free_cache; |
|
} |
|
} else { |
|
ASSERT(num_bitmaps); |
|
num_bitmaps--; |
|
e->bitmap = kmem_cache_zalloc( |
|
btrfs_free_space_bitmap_cachep, GFP_NOFS); |
|
if (!e->bitmap) { |
|
ret = -ENOMEM; |
|
kmem_cache_free( |
|
btrfs_free_space_cachep, e); |
|
goto free_cache; |
|
} |
|
spin_lock(&ctl->tree_lock); |
|
ret = link_free_space(ctl, e); |
|
ctl->total_bitmaps++; |
|
recalculate_thresholds(ctl); |
|
spin_unlock(&ctl->tree_lock); |
|
if (ret) { |
|
btrfs_err(fs_info, |
|
"Duplicate entries in free space cache, dumping"); |
|
kmem_cache_free(btrfs_free_space_cachep, e); |
|
goto free_cache; |
|
} |
|
list_add_tail(&e->list, &bitmaps); |
|
} |
|
|
|
num_entries--; |
|
} |
|
|
|
io_ctl_unmap_page(&io_ctl); |
|
|
|
/* |
|
* We add the bitmaps at the end of the entries in order that |
|
* the bitmap entries are added to the cache. |
|
*/ |
|
list_for_each_entry_safe(e, n, &bitmaps, list) { |
|
list_del_init(&e->list); |
|
ret = io_ctl_read_bitmap(&io_ctl, e); |
|
if (ret) |
|
goto free_cache; |
|
} |
|
|
|
io_ctl_drop_pages(&io_ctl); |
|
ret = 1; |
|
out: |
|
io_ctl_free(&io_ctl); |
|
return ret; |
|
free_cache: |
|
io_ctl_drop_pages(&io_ctl); |
|
__btrfs_remove_free_space_cache(ctl); |
|
goto out; |
|
} |
|
|
|
static int copy_free_space_cache(struct btrfs_block_group *block_group, |
|
struct btrfs_free_space_ctl *ctl) |
|
{ |
|
struct btrfs_free_space *info; |
|
struct rb_node *n; |
|
int ret = 0; |
|
|
|
while (!ret && (n = rb_first(&ctl->free_space_offset)) != NULL) { |
|
info = rb_entry(n, struct btrfs_free_space, offset_index); |
|
if (!info->bitmap) { |
|
unlink_free_space(ctl, info, true); |
|
ret = btrfs_add_free_space(block_group, info->offset, |
|
info->bytes); |
|
kmem_cache_free(btrfs_free_space_cachep, info); |
|
} else { |
|
u64 offset = info->offset; |
|
u64 bytes = ctl->unit; |
|
|
|
while (search_bitmap(ctl, info, &offset, &bytes, |
|
false) == 0) { |
|
ret = btrfs_add_free_space(block_group, offset, |
|
bytes); |
|
if (ret) |
|
break; |
|
bitmap_clear_bits(ctl, info, offset, bytes, true); |
|
offset = info->offset; |
|
bytes = ctl->unit; |
|
} |
|
free_bitmap(ctl, info); |
|
} |
|
cond_resched(); |
|
} |
|
return ret; |
|
} |
|
|
|
int load_free_space_cache(struct btrfs_block_group *block_group) |
|
{ |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space_ctl tmp_ctl = {}; |
|
struct inode *inode; |
|
struct btrfs_path *path; |
|
int ret = 0; |
|
bool matched; |
|
u64 used = block_group->used; |
|
|
|
/* |
|
* Because we could potentially discard our loaded free space, we want |
|
* to load everything into a temporary structure first, and then if it's |
|
* valid copy it all into the actual free space ctl. |
|
*/ |
|
btrfs_init_free_space_ctl(block_group, &tmp_ctl); |
|
|
|
/* |
|
* If this block group has been marked to be cleared for one reason or |
|
* another then we can't trust the on disk cache, so just return. |
|
*/ |
|
spin_lock(&block_group->lock); |
|
if (block_group->disk_cache_state != BTRFS_DC_WRITTEN) { |
|
spin_unlock(&block_group->lock); |
|
return 0; |
|
} |
|
spin_unlock(&block_group->lock); |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return 0; |
|
path->search_commit_root = 1; |
|
path->skip_locking = 1; |
|
|
|
/* |
|
* We must pass a path with search_commit_root set to btrfs_iget in |
|
* order to avoid a deadlock when allocating extents for the tree root. |
|
* |
|
* When we are COWing an extent buffer from the tree root, when looking |
|
* for a free extent, at extent-tree.c:find_free_extent(), we can find |
|
* block group without its free space cache loaded. When we find one |
|
* we must load its space cache which requires reading its free space |
|
* cache's inode item from the root tree. If this inode item is located |
|
* in the same leaf that we started COWing before, then we end up in |
|
* deadlock on the extent buffer (trying to read lock it when we |
|
* previously write locked it). |
|
* |
|
* It's safe to read the inode item using the commit root because |
|
* block groups, once loaded, stay in memory forever (until they are |
|
* removed) as well as their space caches once loaded. New block groups |
|
* once created get their ->cached field set to BTRFS_CACHE_FINISHED so |
|
* we will never try to read their inode item while the fs is mounted. |
|
*/ |
|
inode = lookup_free_space_inode(block_group, path); |
|
if (IS_ERR(inode)) { |
|
btrfs_free_path(path); |
|
return 0; |
|
} |
|
|
|
/* We may have converted the inode and made the cache invalid. */ |
|
spin_lock(&block_group->lock); |
|
if (block_group->disk_cache_state != BTRFS_DC_WRITTEN) { |
|
spin_unlock(&block_group->lock); |
|
btrfs_free_path(path); |
|
goto out; |
|
} |
|
spin_unlock(&block_group->lock); |
|
|
|
ret = __load_free_space_cache(fs_info->tree_root, inode, &tmp_ctl, |
|
path, block_group->start); |
|
btrfs_free_path(path); |
|
if (ret <= 0) |
|
goto out; |
|
|
|
matched = (tmp_ctl.free_space == (block_group->length - used - |
|
block_group->bytes_super)); |
|
|
|
if (matched) { |
|
ret = copy_free_space_cache(block_group, &tmp_ctl); |
|
/* |
|
* ret == 1 means we successfully loaded the free space cache, |
|
* so we need to re-set it here. |
|
*/ |
|
if (ret == 0) |
|
ret = 1; |
|
} else { |
|
__btrfs_remove_free_space_cache(&tmp_ctl); |
|
btrfs_warn(fs_info, |
|
"block group %llu has wrong amount of free space", |
|
block_group->start); |
|
ret = -1; |
|
} |
|
out: |
|
if (ret < 0) { |
|
/* This cache is bogus, make sure it gets cleared */ |
|
spin_lock(&block_group->lock); |
|
block_group->disk_cache_state = BTRFS_DC_CLEAR; |
|
spin_unlock(&block_group->lock); |
|
ret = 0; |
|
|
|
btrfs_warn(fs_info, |
|
"failed to load free space cache for block group %llu, rebuilding it now", |
|
block_group->start); |
|
} |
|
|
|
spin_lock(&ctl->tree_lock); |
|
btrfs_discard_update_discardable(block_group); |
|
spin_unlock(&ctl->tree_lock); |
|
iput(inode); |
|
return ret; |
|
} |
|
|
|
static noinline_for_stack |
|
int write_cache_extent_entries(struct btrfs_io_ctl *io_ctl, |
|
struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_block_group *block_group, |
|
int *entries, int *bitmaps, |
|
struct list_head *bitmap_list) |
|
{ |
|
int ret; |
|
struct btrfs_free_cluster *cluster = NULL; |
|
struct btrfs_free_cluster *cluster_locked = NULL; |
|
struct rb_node *node = rb_first(&ctl->free_space_offset); |
|
struct btrfs_trim_range *trim_entry; |
|
|
|
/* Get the cluster for this block_group if it exists */ |
|
if (block_group && !list_empty(&block_group->cluster_list)) { |
|
cluster = list_entry(block_group->cluster_list.next, |
|
struct btrfs_free_cluster, |
|
block_group_list); |
|
} |
|
|
|
if (!node && cluster) { |
|
cluster_locked = cluster; |
|
spin_lock(&cluster_locked->lock); |
|
node = rb_first(&cluster->root); |
|
cluster = NULL; |
|
} |
|
|
|
/* Write out the extent entries */ |
|
while (node) { |
|
struct btrfs_free_space *e; |
|
|
|
e = rb_entry(node, struct btrfs_free_space, offset_index); |
|
*entries += 1; |
|
|
|
ret = io_ctl_add_entry(io_ctl, e->offset, e->bytes, |
|
e->bitmap); |
|
if (ret) |
|
goto fail; |
|
|
|
if (e->bitmap) { |
|
list_add_tail(&e->list, bitmap_list); |
|
*bitmaps += 1; |
|
} |
|
node = rb_next(node); |
|
if (!node && cluster) { |
|
node = rb_first(&cluster->root); |
|
cluster_locked = cluster; |
|
spin_lock(&cluster_locked->lock); |
|
cluster = NULL; |
|
} |
|
} |
|
if (cluster_locked) { |
|
spin_unlock(&cluster_locked->lock); |
|
cluster_locked = NULL; |
|
} |
|
|
|
/* |
|
* Make sure we don't miss any range that was removed from our rbtree |
|
* because trimming is running. Otherwise after a umount+mount (or crash |
|
* after committing the transaction) we would leak free space and get |
|
* an inconsistent free space cache report from fsck. |
|
*/ |
|
list_for_each_entry(trim_entry, &ctl->trimming_ranges, list) { |
|
ret = io_ctl_add_entry(io_ctl, trim_entry->start, |
|
trim_entry->bytes, NULL); |
|
if (ret) |
|
goto fail; |
|
*entries += 1; |
|
} |
|
|
|
return 0; |
|
fail: |
|
if (cluster_locked) |
|
spin_unlock(&cluster_locked->lock); |
|
return -ENOSPC; |
|
} |
|
|
|
static noinline_for_stack int |
|
update_cache_item(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct inode *inode, |
|
struct btrfs_path *path, u64 offset, |
|
int entries, int bitmaps) |
|
{ |
|
struct btrfs_key key; |
|
struct btrfs_free_space_header *header; |
|
struct extent_buffer *leaf; |
|
int ret; |
|
|
|
key.objectid = BTRFS_FREE_SPACE_OBJECTID; |
|
key.offset = offset; |
|
key.type = 0; |
|
|
|
ret = btrfs_search_slot(trans, root, &key, path, 0, 1); |
|
if (ret < 0) { |
|
clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, inode->i_size - 1, |
|
EXTENT_DELALLOC, 0, 0, NULL); |
|
goto fail; |
|
} |
|
leaf = path->nodes[0]; |
|
if (ret > 0) { |
|
struct btrfs_key found_key; |
|
ASSERT(path->slots[0]); |
|
path->slots[0]--; |
|
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
|
if (found_key.objectid != BTRFS_FREE_SPACE_OBJECTID || |
|
found_key.offset != offset) { |
|
clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, |
|
inode->i_size - 1, EXTENT_DELALLOC, 0, |
|
0, NULL); |
|
btrfs_release_path(path); |
|
goto fail; |
|
} |
|
} |
|
|
|
BTRFS_I(inode)->generation = trans->transid; |
|
header = btrfs_item_ptr(leaf, path->slots[0], |
|
struct btrfs_free_space_header); |
|
btrfs_set_free_space_entries(leaf, header, entries); |
|
btrfs_set_free_space_bitmaps(leaf, header, bitmaps); |
|
btrfs_set_free_space_generation(leaf, header, trans->transid); |
|
btrfs_mark_buffer_dirty(leaf); |
|
btrfs_release_path(path); |
|
|
|
return 0; |
|
|
|
fail: |
|
return -1; |
|
} |
|
|
|
static noinline_for_stack int write_pinned_extent_entries( |
|
struct btrfs_trans_handle *trans, |
|
struct btrfs_block_group *block_group, |
|
struct btrfs_io_ctl *io_ctl, |
|
int *entries) |
|
{ |
|
u64 start, extent_start, extent_end, len; |
|
struct extent_io_tree *unpin = NULL; |
|
int ret; |
|
|
|
if (!block_group) |
|
return 0; |
|
|
|
/* |
|
* We want to add any pinned extents to our free space cache |
|
* so we don't leak the space |
|
* |
|
* We shouldn't have switched the pinned extents yet so this is the |
|
* right one |
|
*/ |
|
unpin = &trans->transaction->pinned_extents; |
|
|
|
start = block_group->start; |
|
|
|
while (start < block_group->start + block_group->length) { |
|
ret = find_first_extent_bit(unpin, start, |
|
&extent_start, &extent_end, |
|
EXTENT_DIRTY, NULL); |
|
if (ret) |
|
return 0; |
|
|
|
/* This pinned extent is out of our range */ |
|
if (extent_start >= block_group->start + block_group->length) |
|
return 0; |
|
|
|
extent_start = max(extent_start, start); |
|
extent_end = min(block_group->start + block_group->length, |
|
extent_end + 1); |
|
len = extent_end - extent_start; |
|
|
|
*entries += 1; |
|
ret = io_ctl_add_entry(io_ctl, extent_start, len, NULL); |
|
if (ret) |
|
return -ENOSPC; |
|
|
|
start = extent_end; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static noinline_for_stack int |
|
write_bitmap_entries(struct btrfs_io_ctl *io_ctl, struct list_head *bitmap_list) |
|
{ |
|
struct btrfs_free_space *entry, *next; |
|
int ret; |
|
|
|
/* Write out the bitmaps */ |
|
list_for_each_entry_safe(entry, next, bitmap_list, list) { |
|
ret = io_ctl_add_bitmap(io_ctl, entry->bitmap); |
|
if (ret) |
|
return -ENOSPC; |
|
list_del_init(&entry->list); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int flush_dirty_cache(struct inode *inode) |
|
{ |
|
int ret; |
|
|
|
ret = btrfs_wait_ordered_range(inode, 0, (u64)-1); |
|
if (ret) |
|
clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, inode->i_size - 1, |
|
EXTENT_DELALLOC, 0, 0, NULL); |
|
|
|
return ret; |
|
} |
|
|
|
static void noinline_for_stack |
|
cleanup_bitmap_list(struct list_head *bitmap_list) |
|
{ |
|
struct btrfs_free_space *entry, *next; |
|
|
|
list_for_each_entry_safe(entry, next, bitmap_list, list) |
|
list_del_init(&entry->list); |
|
} |
|
|
|
static void noinline_for_stack |
|
cleanup_write_cache_enospc(struct inode *inode, |
|
struct btrfs_io_ctl *io_ctl, |
|
struct extent_state **cached_state) |
|
{ |
|
io_ctl_drop_pages(io_ctl); |
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, 0, |
|
i_size_read(inode) - 1, cached_state); |
|
} |
|
|
|
static int __btrfs_wait_cache_io(struct btrfs_root *root, |
|
struct btrfs_trans_handle *trans, |
|
struct btrfs_block_group *block_group, |
|
struct btrfs_io_ctl *io_ctl, |
|
struct btrfs_path *path, u64 offset) |
|
{ |
|
int ret; |
|
struct inode *inode = io_ctl->inode; |
|
|
|
if (!inode) |
|
return 0; |
|
|
|
/* Flush the dirty pages in the cache file. */ |
|
ret = flush_dirty_cache(inode); |
|
if (ret) |
|
goto out; |
|
|
|
/* Update the cache item to tell everyone this cache file is valid. */ |
|
ret = update_cache_item(trans, root, inode, path, offset, |
|
io_ctl->entries, io_ctl->bitmaps); |
|
out: |
|
if (ret) { |
|
invalidate_inode_pages2(inode->i_mapping); |
|
BTRFS_I(inode)->generation = 0; |
|
if (block_group) |
|
btrfs_debug(root->fs_info, |
|
"failed to write free space cache for block group %llu error %d", |
|
block_group->start, ret); |
|
} |
|
btrfs_update_inode(trans, root, BTRFS_I(inode)); |
|
|
|
if (block_group) { |
|
/* the dirty list is protected by the dirty_bgs_lock */ |
|
spin_lock(&trans->transaction->dirty_bgs_lock); |
|
|
|
/* the disk_cache_state is protected by the block group lock */ |
|
spin_lock(&block_group->lock); |
|
|
|
/* |
|
* only mark this as written if we didn't get put back on |
|
* the dirty list while waiting for IO. Otherwise our |
|
* cache state won't be right, and we won't get written again |
|
*/ |
|
if (!ret && list_empty(&block_group->dirty_list)) |
|
block_group->disk_cache_state = BTRFS_DC_WRITTEN; |
|
else if (ret) |
|
block_group->disk_cache_state = BTRFS_DC_ERROR; |
|
|
|
spin_unlock(&block_group->lock); |
|
spin_unlock(&trans->transaction->dirty_bgs_lock); |
|
io_ctl->inode = NULL; |
|
iput(inode); |
|
} |
|
|
|
return ret; |
|
|
|
} |
|
|
|
int btrfs_wait_cache_io(struct btrfs_trans_handle *trans, |
|
struct btrfs_block_group *block_group, |
|
struct btrfs_path *path) |
|
{ |
|
return __btrfs_wait_cache_io(block_group->fs_info->tree_root, trans, |
|
block_group, &block_group->io_ctl, |
|
path, block_group->start); |
|
} |
|
|
|
/** |
|
* Write out cached info to an inode |
|
* |
|
* @root: root the inode belongs to |
|
* @inode: freespace inode we are writing out |
|
* @ctl: free space cache we are going to write out |
|
* @block_group: block_group for this cache if it belongs to a block_group |
|
* @io_ctl: holds context for the io |
|
* @trans: the trans handle |
|
* |
|
* This function writes out a free space cache struct to disk for quick recovery |
|
* on mount. This will return 0 if it was successful in writing the cache out, |
|
* or an errno if it was not. |
|
*/ |
|
static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode, |
|
struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_block_group *block_group, |
|
struct btrfs_io_ctl *io_ctl, |
|
struct btrfs_trans_handle *trans) |
|
{ |
|
struct extent_state *cached_state = NULL; |
|
LIST_HEAD(bitmap_list); |
|
int entries = 0; |
|
int bitmaps = 0; |
|
int ret; |
|
int must_iput = 0; |
|
|
|
if (!i_size_read(inode)) |
|
return -EIO; |
|
|
|
WARN_ON(io_ctl->pages); |
|
ret = io_ctl_init(io_ctl, inode, 1); |
|
if (ret) |
|
return ret; |
|
|
|
if (block_group && (block_group->flags & BTRFS_BLOCK_GROUP_DATA)) { |
|
down_write(&block_group->data_rwsem); |
|
spin_lock(&block_group->lock); |
|
if (block_group->delalloc_bytes) { |
|
block_group->disk_cache_state = BTRFS_DC_WRITTEN; |
|
spin_unlock(&block_group->lock); |
|
up_write(&block_group->data_rwsem); |
|
BTRFS_I(inode)->generation = 0; |
|
ret = 0; |
|
must_iput = 1; |
|
goto out; |
|
} |
|
spin_unlock(&block_group->lock); |
|
} |
|
|
|
/* Lock all pages first so we can lock the extent safely. */ |
|
ret = io_ctl_prepare_pages(io_ctl, false); |
|
if (ret) |
|
goto out_unlock; |
|
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1, |
|
&cached_state); |
|
|
|
io_ctl_set_generation(io_ctl, trans->transid); |
|
|
|
mutex_lock(&ctl->cache_writeout_mutex); |
|
/* Write out the extent entries in the free space cache */ |
|
spin_lock(&ctl->tree_lock); |
|
ret = write_cache_extent_entries(io_ctl, ctl, |
|
block_group, &entries, &bitmaps, |
|
&bitmap_list); |
|
if (ret) |
|
goto out_nospc_locked; |
|
|
|
/* |
|
* Some spaces that are freed in the current transaction are pinned, |
|
* they will be added into free space cache after the transaction is |
|
* committed, we shouldn't lose them. |
|
* |
|
* If this changes while we are working we'll get added back to |
|
* the dirty list and redo it. No locking needed |
|
*/ |
|
ret = write_pinned_extent_entries(trans, block_group, io_ctl, &entries); |
|
if (ret) |
|
goto out_nospc_locked; |
|
|
|
/* |
|
* At last, we write out all the bitmaps and keep cache_writeout_mutex |
|
* locked while doing it because a concurrent trim can be manipulating |
|
* or freeing the bitmap. |
|
*/ |
|
ret = write_bitmap_entries(io_ctl, &bitmap_list); |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
if (ret) |
|
goto out_nospc; |
|
|
|
/* Zero out the rest of the pages just to make sure */ |
|
io_ctl_zero_remaining_pages(io_ctl); |
|
|
|
/* Everything is written out, now we dirty the pages in the file. */ |
|
ret = btrfs_dirty_pages(BTRFS_I(inode), io_ctl->pages, |
|
io_ctl->num_pages, 0, i_size_read(inode), |
|
&cached_state, false); |
|
if (ret) |
|
goto out_nospc; |
|
|
|
if (block_group && (block_group->flags & BTRFS_BLOCK_GROUP_DATA)) |
|
up_write(&block_group->data_rwsem); |
|
/* |
|
* Release the pages and unlock the extent, we will flush |
|
* them out later |
|
*/ |
|
io_ctl_drop_pages(io_ctl); |
|
io_ctl_free(io_ctl); |
|
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, 0, |
|
i_size_read(inode) - 1, &cached_state); |
|
|
|
/* |
|
* at this point the pages are under IO and we're happy, |
|
* The caller is responsible for waiting on them and updating |
|
* the cache and the inode |
|
*/ |
|
io_ctl->entries = entries; |
|
io_ctl->bitmaps = bitmaps; |
|
|
|
ret = btrfs_fdatawrite_range(inode, 0, (u64)-1); |
|
if (ret) |
|
goto out; |
|
|
|
return 0; |
|
|
|
out_nospc_locked: |
|
cleanup_bitmap_list(&bitmap_list); |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
|
|
out_nospc: |
|
cleanup_write_cache_enospc(inode, io_ctl, &cached_state); |
|
|
|
out_unlock: |
|
if (block_group && (block_group->flags & BTRFS_BLOCK_GROUP_DATA)) |
|
up_write(&block_group->data_rwsem); |
|
|
|
out: |
|
io_ctl->inode = NULL; |
|
io_ctl_free(io_ctl); |
|
if (ret) { |
|
invalidate_inode_pages2(inode->i_mapping); |
|
BTRFS_I(inode)->generation = 0; |
|
} |
|
btrfs_update_inode(trans, root, BTRFS_I(inode)); |
|
if (must_iput) |
|
iput(inode); |
|
return ret; |
|
} |
|
|
|
int btrfs_write_out_cache(struct btrfs_trans_handle *trans, |
|
struct btrfs_block_group *block_group, |
|
struct btrfs_path *path) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct inode *inode; |
|
int ret = 0; |
|
|
|
spin_lock(&block_group->lock); |
|
if (block_group->disk_cache_state < BTRFS_DC_SETUP) { |
|
spin_unlock(&block_group->lock); |
|
return 0; |
|
} |
|
spin_unlock(&block_group->lock); |
|
|
|
inode = lookup_free_space_inode(block_group, path); |
|
if (IS_ERR(inode)) |
|
return 0; |
|
|
|
ret = __btrfs_write_out_cache(fs_info->tree_root, inode, ctl, |
|
block_group, &block_group->io_ctl, trans); |
|
if (ret) { |
|
btrfs_debug(fs_info, |
|
"failed to write free space cache for block group %llu error %d", |
|
block_group->start, ret); |
|
spin_lock(&block_group->lock); |
|
block_group->disk_cache_state = BTRFS_DC_ERROR; |
|
spin_unlock(&block_group->lock); |
|
|
|
block_group->io_ctl.inode = NULL; |
|
iput(inode); |
|
} |
|
|
|
/* |
|
* if ret == 0 the caller is expected to call btrfs_wait_cache_io |
|
* to wait for IO and put the inode |
|
*/ |
|
|
|
return ret; |
|
} |
|
|
|
static inline unsigned long offset_to_bit(u64 bitmap_start, u32 unit, |
|
u64 offset) |
|
{ |
|
ASSERT(offset >= bitmap_start); |
|
offset -= bitmap_start; |
|
return (unsigned long)(div_u64(offset, unit)); |
|
} |
|
|
|
static inline unsigned long bytes_to_bits(u64 bytes, u32 unit) |
|
{ |
|
return (unsigned long)(div_u64(bytes, unit)); |
|
} |
|
|
|
static inline u64 offset_to_bitmap(struct btrfs_free_space_ctl *ctl, |
|
u64 offset) |
|
{ |
|
u64 bitmap_start; |
|
u64 bytes_per_bitmap; |
|
|
|
bytes_per_bitmap = BITS_PER_BITMAP * ctl->unit; |
|
bitmap_start = offset - ctl->start; |
|
bitmap_start = div64_u64(bitmap_start, bytes_per_bitmap); |
|
bitmap_start *= bytes_per_bitmap; |
|
bitmap_start += ctl->start; |
|
|
|
return bitmap_start; |
|
} |
|
|
|
static int tree_insert_offset(struct rb_root *root, u64 offset, |
|
struct rb_node *node, int bitmap) |
|
{ |
|
struct rb_node **p = &root->rb_node; |
|
struct rb_node *parent = NULL; |
|
struct btrfs_free_space *info; |
|
|
|
while (*p) { |
|
parent = *p; |
|
info = rb_entry(parent, struct btrfs_free_space, offset_index); |
|
|
|
if (offset < info->offset) { |
|
p = &(*p)->rb_left; |
|
} else if (offset > info->offset) { |
|
p = &(*p)->rb_right; |
|
} else { |
|
/* |
|
* we could have a bitmap entry and an extent entry |
|
* share the same offset. If this is the case, we want |
|
* the extent entry to always be found first if we do a |
|
* linear search through the tree, since we want to have |
|
* the quickest allocation time, and allocating from an |
|
* extent is faster than allocating from a bitmap. So |
|
* if we're inserting a bitmap and we find an entry at |
|
* this offset, we want to go right, or after this entry |
|
* logically. If we are inserting an extent and we've |
|
* found a bitmap, we want to go left, or before |
|
* logically. |
|
*/ |
|
if (bitmap) { |
|
if (info->bitmap) { |
|
WARN_ON_ONCE(1); |
|
return -EEXIST; |
|
} |
|
p = &(*p)->rb_right; |
|
} else { |
|
if (!info->bitmap) { |
|
WARN_ON_ONCE(1); |
|
return -EEXIST; |
|
} |
|
p = &(*p)->rb_left; |
|
} |
|
} |
|
} |
|
|
|
rb_link_node(node, parent, p); |
|
rb_insert_color(node, root); |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* This is a little subtle. We *only* have ->max_extent_size set if we actually |
|
* searched through the bitmap and figured out the largest ->max_extent_size, |
|
* otherwise it's 0. In the case that it's 0 we don't want to tell the |
|
* allocator the wrong thing, we want to use the actual real max_extent_size |
|
* we've found already if it's larger, or we want to use ->bytes. |
|
* |
|
* This matters because find_free_space() will skip entries who's ->bytes is |
|
* less than the required bytes. So if we didn't search down this bitmap, we |
|
* may pick some previous entry that has a smaller ->max_extent_size than we |
|
* have. For example, assume we have two entries, one that has |
|
* ->max_extent_size set to 4K and ->bytes set to 1M. A second entry hasn't set |
|
* ->max_extent_size yet, has ->bytes set to 8K and it's contiguous. We will |
|
* call into find_free_space(), and return with max_extent_size == 4K, because |
|
* that first bitmap entry had ->max_extent_size set, but the second one did |
|
* not. If instead we returned 8K we'd come in searching for 8K, and find the |
|
* 8K contiguous range. |
|
* |
|
* Consider the other case, we have 2 8K chunks in that second entry and still |
|
* don't have ->max_extent_size set. We'll return 16K, and the next time the |
|
* allocator comes in it'll fully search our second bitmap, and this time it'll |
|
* get an uptodate value of 8K as the maximum chunk size. Then we'll get the |
|
* right allocation the next loop through. |
|
*/ |
|
static inline u64 get_max_extent_size(const struct btrfs_free_space *entry) |
|
{ |
|
if (entry->bitmap && entry->max_extent_size) |
|
return entry->max_extent_size; |
|
return entry->bytes; |
|
} |
|
|
|
/* |
|
* We want the largest entry to be leftmost, so this is inverted from what you'd |
|
* normally expect. |
|
*/ |
|
static bool entry_less(struct rb_node *node, const struct rb_node *parent) |
|
{ |
|
const struct btrfs_free_space *entry, *exist; |
|
|
|
entry = rb_entry(node, struct btrfs_free_space, bytes_index); |
|
exist = rb_entry(parent, struct btrfs_free_space, bytes_index); |
|
return get_max_extent_size(exist) < get_max_extent_size(entry); |
|
} |
|
|
|
/* |
|
* searches the tree for the given offset. |
|
* |
|
* fuzzy - If this is set, then we are trying to make an allocation, and we just |
|
* want a section that has at least bytes size and comes at or after the given |
|
* offset. |
|
*/ |
|
static struct btrfs_free_space * |
|
tree_search_offset(struct btrfs_free_space_ctl *ctl, |
|
u64 offset, int bitmap_only, int fuzzy) |
|
{ |
|
struct rb_node *n = ctl->free_space_offset.rb_node; |
|
struct btrfs_free_space *entry = NULL, *prev = NULL; |
|
|
|
/* find entry that is closest to the 'offset' */ |
|
while (n) { |
|
entry = rb_entry(n, struct btrfs_free_space, offset_index); |
|
prev = entry; |
|
|
|
if (offset < entry->offset) |
|
n = n->rb_left; |
|
else if (offset > entry->offset) |
|
n = n->rb_right; |
|
else |
|
break; |
|
|
|
entry = NULL; |
|
} |
|
|
|
if (bitmap_only) { |
|
if (!entry) |
|
return NULL; |
|
if (entry->bitmap) |
|
return entry; |
|
|
|
/* |
|
* bitmap entry and extent entry may share same offset, |
|
* in that case, bitmap entry comes after extent entry. |
|
*/ |
|
n = rb_next(n); |
|
if (!n) |
|
return NULL; |
|
entry = rb_entry(n, struct btrfs_free_space, offset_index); |
|
if (entry->offset != offset) |
|
return NULL; |
|
|
|
WARN_ON(!entry->bitmap); |
|
return entry; |
|
} else if (entry) { |
|
if (entry->bitmap) { |
|
/* |
|
* if previous extent entry covers the offset, |
|
* we should return it instead of the bitmap entry |
|
*/ |
|
n = rb_prev(&entry->offset_index); |
|
if (n) { |
|
prev = rb_entry(n, struct btrfs_free_space, |
|
offset_index); |
|
if (!prev->bitmap && |
|
prev->offset + prev->bytes > offset) |
|
entry = prev; |
|
} |
|
} |
|
return entry; |
|
} |
|
|
|
if (!prev) |
|
return NULL; |
|
|
|
/* find last entry before the 'offset' */ |
|
entry = prev; |
|
if (entry->offset > offset) { |
|
n = rb_prev(&entry->offset_index); |
|
if (n) { |
|
entry = rb_entry(n, struct btrfs_free_space, |
|
offset_index); |
|
ASSERT(entry->offset <= offset); |
|
} else { |
|
if (fuzzy) |
|
return entry; |
|
else |
|
return NULL; |
|
} |
|
} |
|
|
|
if (entry->bitmap) { |
|
n = rb_prev(&entry->offset_index); |
|
if (n) { |
|
prev = rb_entry(n, struct btrfs_free_space, |
|
offset_index); |
|
if (!prev->bitmap && |
|
prev->offset + prev->bytes > offset) |
|
return prev; |
|
} |
|
if (entry->offset + BITS_PER_BITMAP * ctl->unit > offset) |
|
return entry; |
|
} else if (entry->offset + entry->bytes > offset) |
|
return entry; |
|
|
|
if (!fuzzy) |
|
return NULL; |
|
|
|
while (1) { |
|
n = rb_next(&entry->offset_index); |
|
if (!n) |
|
return NULL; |
|
entry = rb_entry(n, struct btrfs_free_space, offset_index); |
|
if (entry->bitmap) { |
|
if (entry->offset + BITS_PER_BITMAP * |
|
ctl->unit > offset) |
|
break; |
|
} else { |
|
if (entry->offset + entry->bytes > offset) |
|
break; |
|
} |
|
} |
|
return entry; |
|
} |
|
|
|
static inline void unlink_free_space(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, |
|
bool update_stat) |
|
{ |
|
rb_erase(&info->offset_index, &ctl->free_space_offset); |
|
rb_erase_cached(&info->bytes_index, &ctl->free_space_bytes); |
|
ctl->free_extents--; |
|
|
|
if (!info->bitmap && !btrfs_free_space_trimmed(info)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR]--; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] -= info->bytes; |
|
} |
|
|
|
if (update_stat) |
|
ctl->free_space -= info->bytes; |
|
} |
|
|
|
static int link_free_space(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info) |
|
{ |
|
int ret = 0; |
|
|
|
ASSERT(info->bytes || info->bitmap); |
|
ret = tree_insert_offset(&ctl->free_space_offset, info->offset, |
|
&info->offset_index, (info->bitmap != NULL)); |
|
if (ret) |
|
return ret; |
|
|
|
rb_add_cached(&info->bytes_index, &ctl->free_space_bytes, entry_less); |
|
|
|
if (!info->bitmap && !btrfs_free_space_trimmed(info)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR]++; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] += info->bytes; |
|
} |
|
|
|
ctl->free_space += info->bytes; |
|
ctl->free_extents++; |
|
return ret; |
|
} |
|
|
|
static void relink_bitmap_entry(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info) |
|
{ |
|
ASSERT(info->bitmap); |
|
|
|
/* |
|
* If our entry is empty it's because we're on a cluster and we don't |
|
* want to re-link it into our ctl bytes index. |
|
*/ |
|
if (RB_EMPTY_NODE(&info->bytes_index)) |
|
return; |
|
|
|
rb_erase_cached(&info->bytes_index, &ctl->free_space_bytes); |
|
rb_add_cached(&info->bytes_index, &ctl->free_space_bytes, entry_less); |
|
} |
|
|
|
static inline void bitmap_clear_bits(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, |
|
u64 offset, u64 bytes, bool update_stat) |
|
{ |
|
unsigned long start, count, end; |
|
int extent_delta = -1; |
|
|
|
start = offset_to_bit(info->offset, ctl->unit, offset); |
|
count = bytes_to_bits(bytes, ctl->unit); |
|
end = start + count; |
|
ASSERT(end <= BITS_PER_BITMAP); |
|
|
|
bitmap_clear(info->bitmap, start, count); |
|
|
|
info->bytes -= bytes; |
|
if (info->max_extent_size > ctl->unit) |
|
info->max_extent_size = 0; |
|
|
|
relink_bitmap_entry(ctl, info); |
|
|
|
if (start && test_bit(start - 1, info->bitmap)) |
|
extent_delta++; |
|
|
|
if (end < BITS_PER_BITMAP && test_bit(end, info->bitmap)) |
|
extent_delta++; |
|
|
|
info->bitmap_extents += extent_delta; |
|
if (!btrfs_free_space_trimmed(info)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR] += extent_delta; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] -= bytes; |
|
} |
|
|
|
if (update_stat) |
|
ctl->free_space -= bytes; |
|
} |
|
|
|
static void bitmap_set_bits(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, u64 offset, |
|
u64 bytes) |
|
{ |
|
unsigned long start, count, end; |
|
int extent_delta = 1; |
|
|
|
start = offset_to_bit(info->offset, ctl->unit, offset); |
|
count = bytes_to_bits(bytes, ctl->unit); |
|
end = start + count; |
|
ASSERT(end <= BITS_PER_BITMAP); |
|
|
|
bitmap_set(info->bitmap, start, count); |
|
|
|
/* |
|
* We set some bytes, we have no idea what the max extent size is |
|
* anymore. |
|
*/ |
|
info->max_extent_size = 0; |
|
info->bytes += bytes; |
|
ctl->free_space += bytes; |
|
|
|
relink_bitmap_entry(ctl, info); |
|
|
|
if (start && test_bit(start - 1, info->bitmap)) |
|
extent_delta--; |
|
|
|
if (end < BITS_PER_BITMAP && test_bit(end, info->bitmap)) |
|
extent_delta--; |
|
|
|
info->bitmap_extents += extent_delta; |
|
if (!btrfs_free_space_trimmed(info)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR] += extent_delta; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] += bytes; |
|
} |
|
} |
|
|
|
/* |
|
* If we can not find suitable extent, we will use bytes to record |
|
* the size of the max extent. |
|
*/ |
|
static int search_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *bitmap_info, u64 *offset, |
|
u64 *bytes, bool for_alloc) |
|
{ |
|
unsigned long found_bits = 0; |
|
unsigned long max_bits = 0; |
|
unsigned long bits, i; |
|
unsigned long next_zero; |
|
unsigned long extent_bits; |
|
|
|
/* |
|
* Skip searching the bitmap if we don't have a contiguous section that |
|
* is large enough for this allocation. |
|
*/ |
|
if (for_alloc && |
|
bitmap_info->max_extent_size && |
|
bitmap_info->max_extent_size < *bytes) { |
|
*bytes = bitmap_info->max_extent_size; |
|
return -1; |
|
} |
|
|
|
i = offset_to_bit(bitmap_info->offset, ctl->unit, |
|
max_t(u64, *offset, bitmap_info->offset)); |
|
bits = bytes_to_bits(*bytes, ctl->unit); |
|
|
|
for_each_set_bit_from(i, bitmap_info->bitmap, BITS_PER_BITMAP) { |
|
if (for_alloc && bits == 1) { |
|
found_bits = 1; |
|
break; |
|
} |
|
next_zero = find_next_zero_bit(bitmap_info->bitmap, |
|
BITS_PER_BITMAP, i); |
|
extent_bits = next_zero - i; |
|
if (extent_bits >= bits) { |
|
found_bits = extent_bits; |
|
break; |
|
} else if (extent_bits > max_bits) { |
|
max_bits = extent_bits; |
|
} |
|
i = next_zero; |
|
} |
|
|
|
if (found_bits) { |
|
*offset = (u64)(i * ctl->unit) + bitmap_info->offset; |
|
*bytes = (u64)(found_bits) * ctl->unit; |
|
return 0; |
|
} |
|
|
|
*bytes = (u64)(max_bits) * ctl->unit; |
|
bitmap_info->max_extent_size = *bytes; |
|
relink_bitmap_entry(ctl, bitmap_info); |
|
return -1; |
|
} |
|
|
|
/* Cache the size of the max extent in bytes */ |
|
static struct btrfs_free_space * |
|
find_free_space(struct btrfs_free_space_ctl *ctl, u64 *offset, u64 *bytes, |
|
unsigned long align, u64 *max_extent_size, bool use_bytes_index) |
|
{ |
|
struct btrfs_free_space *entry; |
|
struct rb_node *node; |
|
u64 tmp; |
|
u64 align_off; |
|
int ret; |
|
|
|
if (!ctl->free_space_offset.rb_node) |
|
goto out; |
|
again: |
|
if (use_bytes_index) { |
|
node = rb_first_cached(&ctl->free_space_bytes); |
|
} else { |
|
entry = tree_search_offset(ctl, offset_to_bitmap(ctl, *offset), |
|
0, 1); |
|
if (!entry) |
|
goto out; |
|
node = &entry->offset_index; |
|
} |
|
|
|
for (; node; node = rb_next(node)) { |
|
if (use_bytes_index) |
|
entry = rb_entry(node, struct btrfs_free_space, |
|
bytes_index); |
|
else |
|
entry = rb_entry(node, struct btrfs_free_space, |
|
offset_index); |
|
|
|
/* |
|
* If we are using the bytes index then all subsequent entries |
|
* in this tree are going to be < bytes, so simply set the max |
|
* extent size and exit the loop. |
|
* |
|
* If we're using the offset index then we need to keep going |
|
* through the rest of the tree. |
|
*/ |
|
if (entry->bytes < *bytes) { |
|
*max_extent_size = max(get_max_extent_size(entry), |
|
*max_extent_size); |
|
if (use_bytes_index) |
|
break; |
|
continue; |
|
} |
|
|
|
/* make sure the space returned is big enough |
|
* to match our requested alignment |
|
*/ |
|
if (*bytes >= align) { |
|
tmp = entry->offset - ctl->start + align - 1; |
|
tmp = div64_u64(tmp, align); |
|
tmp = tmp * align + ctl->start; |
|
align_off = tmp - entry->offset; |
|
} else { |
|
align_off = 0; |
|
tmp = entry->offset; |
|
} |
|
|
|
/* |
|
* We don't break here if we're using the bytes index because we |
|
* may have another entry that has the correct alignment that is |
|
* the right size, so we don't want to miss that possibility. |
|
* At worst this adds another loop through the logic, but if we |
|
* broke here we could prematurely ENOSPC. |
|
*/ |
|
if (entry->bytes < *bytes + align_off) { |
|
*max_extent_size = max(get_max_extent_size(entry), |
|
*max_extent_size); |
|
continue; |
|
} |
|
|
|
if (entry->bitmap) { |
|
struct rb_node *old_next = rb_next(node); |
|
u64 size = *bytes; |
|
|
|
ret = search_bitmap(ctl, entry, &tmp, &size, true); |
|
if (!ret) { |
|
*offset = tmp; |
|
*bytes = size; |
|
return entry; |
|
} else { |
|
*max_extent_size = |
|
max(get_max_extent_size(entry), |
|
*max_extent_size); |
|
} |
|
|
|
/* |
|
* The bitmap may have gotten re-arranged in the space |
|
* index here because the max_extent_size may have been |
|
* updated. Start from the beginning again if this |
|
* happened. |
|
*/ |
|
if (use_bytes_index && old_next != rb_next(node)) |
|
goto again; |
|
continue; |
|
} |
|
|
|
*offset = tmp; |
|
*bytes = entry->bytes - align_off; |
|
return entry; |
|
} |
|
out: |
|
return NULL; |
|
} |
|
|
|
static void add_new_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, u64 offset) |
|
{ |
|
info->offset = offset_to_bitmap(ctl, offset); |
|
info->bytes = 0; |
|
info->bitmap_extents = 0; |
|
INIT_LIST_HEAD(&info->list); |
|
link_free_space(ctl, info); |
|
ctl->total_bitmaps++; |
|
recalculate_thresholds(ctl); |
|
} |
|
|
|
static void free_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *bitmap_info) |
|
{ |
|
/* |
|
* Normally when this is called, the bitmap is completely empty. However, |
|
* if we are blowing up the free space cache for one reason or another |
|
* via __btrfs_remove_free_space_cache(), then it may not be freed and |
|
* we may leave stats on the table. |
|
*/ |
|
if (bitmap_info->bytes && !btrfs_free_space_trimmed(bitmap_info)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR] -= |
|
bitmap_info->bitmap_extents; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] -= bitmap_info->bytes; |
|
|
|
} |
|
unlink_free_space(ctl, bitmap_info, true); |
|
kmem_cache_free(btrfs_free_space_bitmap_cachep, bitmap_info->bitmap); |
|
kmem_cache_free(btrfs_free_space_cachep, bitmap_info); |
|
ctl->total_bitmaps--; |
|
recalculate_thresholds(ctl); |
|
} |
|
|
|
static noinline int remove_from_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *bitmap_info, |
|
u64 *offset, u64 *bytes) |
|
{ |
|
u64 end; |
|
u64 search_start, search_bytes; |
|
int ret; |
|
|
|
again: |
|
end = bitmap_info->offset + (u64)(BITS_PER_BITMAP * ctl->unit) - 1; |
|
|
|
/* |
|
* We need to search for bits in this bitmap. We could only cover some |
|
* of the extent in this bitmap thanks to how we add space, so we need |
|
* to search for as much as it as we can and clear that amount, and then |
|
* go searching for the next bit. |
|
*/ |
|
search_start = *offset; |
|
search_bytes = ctl->unit; |
|
search_bytes = min(search_bytes, end - search_start + 1); |
|
ret = search_bitmap(ctl, bitmap_info, &search_start, &search_bytes, |
|
false); |
|
if (ret < 0 || search_start != *offset) |
|
return -EINVAL; |
|
|
|
/* We may have found more bits than what we need */ |
|
search_bytes = min(search_bytes, *bytes); |
|
|
|
/* Cannot clear past the end of the bitmap */ |
|
search_bytes = min(search_bytes, end - search_start + 1); |
|
|
|
bitmap_clear_bits(ctl, bitmap_info, search_start, search_bytes, true); |
|
*offset += search_bytes; |
|
*bytes -= search_bytes; |
|
|
|
if (*bytes) { |
|
struct rb_node *next = rb_next(&bitmap_info->offset_index); |
|
if (!bitmap_info->bytes) |
|
free_bitmap(ctl, bitmap_info); |
|
|
|
/* |
|
* no entry after this bitmap, but we still have bytes to |
|
* remove, so something has gone wrong. |
|
*/ |
|
if (!next) |
|
return -EINVAL; |
|
|
|
bitmap_info = rb_entry(next, struct btrfs_free_space, |
|
offset_index); |
|
|
|
/* |
|
* if the next entry isn't a bitmap we need to return to let the |
|
* extent stuff do its work. |
|
*/ |
|
if (!bitmap_info->bitmap) |
|
return -EAGAIN; |
|
|
|
/* |
|
* Ok the next item is a bitmap, but it may not actually hold |
|
* the information for the rest of this free space stuff, so |
|
* look for it, and if we don't find it return so we can try |
|
* everything over again. |
|
*/ |
|
search_start = *offset; |
|
search_bytes = ctl->unit; |
|
ret = search_bitmap(ctl, bitmap_info, &search_start, |
|
&search_bytes, false); |
|
if (ret < 0 || search_start != *offset) |
|
return -EAGAIN; |
|
|
|
goto again; |
|
} else if (!bitmap_info->bytes) |
|
free_bitmap(ctl, bitmap_info); |
|
|
|
return 0; |
|
} |
|
|
|
static u64 add_bytes_to_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, u64 offset, |
|
u64 bytes, enum btrfs_trim_state trim_state) |
|
{ |
|
u64 bytes_to_set = 0; |
|
u64 end; |
|
|
|
/* |
|
* This is a tradeoff to make bitmap trim state minimal. We mark the |
|
* whole bitmap untrimmed if at any point we add untrimmed regions. |
|
*/ |
|
if (trim_state == BTRFS_TRIM_STATE_UNTRIMMED) { |
|
if (btrfs_free_space_trimmed(info)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR] += |
|
info->bitmap_extents; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] += info->bytes; |
|
} |
|
info->trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
} |
|
|
|
end = info->offset + (u64)(BITS_PER_BITMAP * ctl->unit); |
|
|
|
bytes_to_set = min(end - offset, bytes); |
|
|
|
bitmap_set_bits(ctl, info, offset, bytes_to_set); |
|
|
|
return bytes_to_set; |
|
|
|
} |
|
|
|
static bool use_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info) |
|
{ |
|
struct btrfs_block_group *block_group = ctl->block_group; |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
bool forced = false; |
|
|
|
#ifdef CONFIG_BTRFS_DEBUG |
|
if (btrfs_should_fragment_free_space(block_group)) |
|
forced = true; |
|
#endif |
|
|
|
/* This is a way to reclaim large regions from the bitmaps. */ |
|
if (!forced && info->bytes >= FORCE_EXTENT_THRESHOLD) |
|
return false; |
|
|
|
/* |
|
* If we are below the extents threshold then we can add this as an |
|
* extent, and don't have to deal with the bitmap |
|
*/ |
|
if (!forced && ctl->free_extents < ctl->extents_thresh) { |
|
/* |
|
* If this block group has some small extents we don't want to |
|
* use up all of our free slots in the cache with them, we want |
|
* to reserve them to larger extents, however if we have plenty |
|
* of cache left then go ahead an dadd them, no sense in adding |
|
* the overhead of a bitmap if we don't have to. |
|
*/ |
|
if (info->bytes <= fs_info->sectorsize * 8) { |
|
if (ctl->free_extents * 3 <= ctl->extents_thresh) |
|
return false; |
|
} else { |
|
return false; |
|
} |
|
} |
|
|
|
/* |
|
* The original block groups from mkfs can be really small, like 8 |
|
* megabytes, so don't bother with a bitmap for those entries. However |
|
* some block groups can be smaller than what a bitmap would cover but |
|
* are still large enough that they could overflow the 32k memory limit, |
|
* so allow those block groups to still be allowed to have a bitmap |
|
* entry. |
|
*/ |
|
if (((BITS_PER_BITMAP * ctl->unit) >> 1) > block_group->length) |
|
return false; |
|
|
|
return true; |
|
} |
|
|
|
static const struct btrfs_free_space_op free_space_op = { |
|
.use_bitmap = use_bitmap, |
|
}; |
|
|
|
static int insert_into_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info) |
|
{ |
|
struct btrfs_free_space *bitmap_info; |
|
struct btrfs_block_group *block_group = NULL; |
|
int added = 0; |
|
u64 bytes, offset, bytes_added; |
|
enum btrfs_trim_state trim_state; |
|
int ret; |
|
|
|
bytes = info->bytes; |
|
offset = info->offset; |
|
trim_state = info->trim_state; |
|
|
|
if (!ctl->op->use_bitmap(ctl, info)) |
|
return 0; |
|
|
|
if (ctl->op == &free_space_op) |
|
block_group = ctl->block_group; |
|
again: |
|
/* |
|
* Since we link bitmaps right into the cluster we need to see if we |
|
* have a cluster here, and if so and it has our bitmap we need to add |
|
* the free space to that bitmap. |
|
*/ |
|
if (block_group && !list_empty(&block_group->cluster_list)) { |
|
struct btrfs_free_cluster *cluster; |
|
struct rb_node *node; |
|
struct btrfs_free_space *entry; |
|
|
|
cluster = list_entry(block_group->cluster_list.next, |
|
struct btrfs_free_cluster, |
|
block_group_list); |
|
spin_lock(&cluster->lock); |
|
node = rb_first(&cluster->root); |
|
if (!node) { |
|
spin_unlock(&cluster->lock); |
|
goto no_cluster_bitmap; |
|
} |
|
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index); |
|
if (!entry->bitmap) { |
|
spin_unlock(&cluster->lock); |
|
goto no_cluster_bitmap; |
|
} |
|
|
|
if (entry->offset == offset_to_bitmap(ctl, offset)) { |
|
bytes_added = add_bytes_to_bitmap(ctl, entry, offset, |
|
bytes, trim_state); |
|
bytes -= bytes_added; |
|
offset += bytes_added; |
|
} |
|
spin_unlock(&cluster->lock); |
|
if (!bytes) { |
|
ret = 1; |
|
goto out; |
|
} |
|
} |
|
|
|
no_cluster_bitmap: |
|
bitmap_info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset), |
|
1, 0); |
|
if (!bitmap_info) { |
|
ASSERT(added == 0); |
|
goto new_bitmap; |
|
} |
|
|
|
bytes_added = add_bytes_to_bitmap(ctl, bitmap_info, offset, bytes, |
|
trim_state); |
|
bytes -= bytes_added; |
|
offset += bytes_added; |
|
added = 0; |
|
|
|
if (!bytes) { |
|
ret = 1; |
|
goto out; |
|
} else |
|
goto again; |
|
|
|
new_bitmap: |
|
if (info && info->bitmap) { |
|
add_new_bitmap(ctl, info, offset); |
|
added = 1; |
|
info = NULL; |
|
goto again; |
|
} else { |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
/* no pre-allocated info, allocate a new one */ |
|
if (!info) { |
|
info = kmem_cache_zalloc(btrfs_free_space_cachep, |
|
GFP_NOFS); |
|
if (!info) { |
|
spin_lock(&ctl->tree_lock); |
|
ret = -ENOMEM; |
|
goto out; |
|
} |
|
} |
|
|
|
/* allocate the bitmap */ |
|
info->bitmap = kmem_cache_zalloc(btrfs_free_space_bitmap_cachep, |
|
GFP_NOFS); |
|
info->trim_state = BTRFS_TRIM_STATE_TRIMMED; |
|
spin_lock(&ctl->tree_lock); |
|
if (!info->bitmap) { |
|
ret = -ENOMEM; |
|
goto out; |
|
} |
|
goto again; |
|
} |
|
|
|
out: |
|
if (info) { |
|
if (info->bitmap) |
|
kmem_cache_free(btrfs_free_space_bitmap_cachep, |
|
info->bitmap); |
|
kmem_cache_free(btrfs_free_space_cachep, info); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* Free space merging rules: |
|
* 1) Merge trimmed areas together |
|
* 2) Let untrimmed areas coalesce with trimmed areas |
|
* 3) Always pull neighboring regions from bitmaps |
|
* |
|
* The above rules are for when we merge free space based on btrfs_trim_state. |
|
* Rules 2 and 3 are subtle because they are suboptimal, but are done for the |
|
* same reason: to promote larger extent regions which makes life easier for |
|
* find_free_extent(). Rule 2 enables coalescing based on the common path |
|
* being returning free space from btrfs_finish_extent_commit(). So when free |
|
* space is trimmed, it will prevent aggregating trimmed new region and |
|
* untrimmed regions in the rb_tree. Rule 3 is purely to obtain larger extents |
|
* and provide find_free_extent() with the largest extents possible hoping for |
|
* the reuse path. |
|
*/ |
|
static bool try_merge_free_space(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, bool update_stat) |
|
{ |
|
struct btrfs_free_space *left_info = NULL; |
|
struct btrfs_free_space *right_info; |
|
bool merged = false; |
|
u64 offset = info->offset; |
|
u64 bytes = info->bytes; |
|
const bool is_trimmed = btrfs_free_space_trimmed(info); |
|
|
|
/* |
|
* first we want to see if there is free space adjacent to the range we |
|
* are adding, if there is remove that struct and add a new one to |
|
* cover the entire range |
|
*/ |
|
right_info = tree_search_offset(ctl, offset + bytes, 0, 0); |
|
if (right_info && rb_prev(&right_info->offset_index)) |
|
left_info = rb_entry(rb_prev(&right_info->offset_index), |
|
struct btrfs_free_space, offset_index); |
|
else if (!right_info) |
|
left_info = tree_search_offset(ctl, offset - 1, 0, 0); |
|
|
|
/* See try_merge_free_space() comment. */ |
|
if (right_info && !right_info->bitmap && |
|
(!is_trimmed || btrfs_free_space_trimmed(right_info))) { |
|
unlink_free_space(ctl, right_info, update_stat); |
|
info->bytes += right_info->bytes; |
|
kmem_cache_free(btrfs_free_space_cachep, right_info); |
|
merged = true; |
|
} |
|
|
|
/* See try_merge_free_space() comment. */ |
|
if (left_info && !left_info->bitmap && |
|
left_info->offset + left_info->bytes == offset && |
|
(!is_trimmed || btrfs_free_space_trimmed(left_info))) { |
|
unlink_free_space(ctl, left_info, update_stat); |
|
info->offset = left_info->offset; |
|
info->bytes += left_info->bytes; |
|
kmem_cache_free(btrfs_free_space_cachep, left_info); |
|
merged = true; |
|
} |
|
|
|
return merged; |
|
} |
|
|
|
static bool steal_from_bitmap_to_end(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, |
|
bool update_stat) |
|
{ |
|
struct btrfs_free_space *bitmap; |
|
unsigned long i; |
|
unsigned long j; |
|
const u64 end = info->offset + info->bytes; |
|
const u64 bitmap_offset = offset_to_bitmap(ctl, end); |
|
u64 bytes; |
|
|
|
bitmap = tree_search_offset(ctl, bitmap_offset, 1, 0); |
|
if (!bitmap) |
|
return false; |
|
|
|
i = offset_to_bit(bitmap->offset, ctl->unit, end); |
|
j = find_next_zero_bit(bitmap->bitmap, BITS_PER_BITMAP, i); |
|
if (j == i) |
|
return false; |
|
bytes = (j - i) * ctl->unit; |
|
info->bytes += bytes; |
|
|
|
/* See try_merge_free_space() comment. */ |
|
if (!btrfs_free_space_trimmed(bitmap)) |
|
info->trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
|
|
bitmap_clear_bits(ctl, bitmap, end, bytes, update_stat); |
|
|
|
if (!bitmap->bytes) |
|
free_bitmap(ctl, bitmap); |
|
|
|
return true; |
|
} |
|
|
|
static bool steal_from_bitmap_to_front(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, |
|
bool update_stat) |
|
{ |
|
struct btrfs_free_space *bitmap; |
|
u64 bitmap_offset; |
|
unsigned long i; |
|
unsigned long j; |
|
unsigned long prev_j; |
|
u64 bytes; |
|
|
|
bitmap_offset = offset_to_bitmap(ctl, info->offset); |
|
/* If we're on a boundary, try the previous logical bitmap. */ |
|
if (bitmap_offset == info->offset) { |
|
if (info->offset == 0) |
|
return false; |
|
bitmap_offset = offset_to_bitmap(ctl, info->offset - 1); |
|
} |
|
|
|
bitmap = tree_search_offset(ctl, bitmap_offset, 1, 0); |
|
if (!bitmap) |
|
return false; |
|
|
|
i = offset_to_bit(bitmap->offset, ctl->unit, info->offset) - 1; |
|
j = 0; |
|
prev_j = (unsigned long)-1; |
|
for_each_clear_bit_from(j, bitmap->bitmap, BITS_PER_BITMAP) { |
|
if (j > i) |
|
break; |
|
prev_j = j; |
|
} |
|
if (prev_j == i) |
|
return false; |
|
|
|
if (prev_j == (unsigned long)-1) |
|
bytes = (i + 1) * ctl->unit; |
|
else |
|
bytes = (i - prev_j) * ctl->unit; |
|
|
|
info->offset -= bytes; |
|
info->bytes += bytes; |
|
|
|
/* See try_merge_free_space() comment. */ |
|
if (!btrfs_free_space_trimmed(bitmap)) |
|
info->trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
|
|
bitmap_clear_bits(ctl, bitmap, info->offset, bytes, update_stat); |
|
|
|
if (!bitmap->bytes) |
|
free_bitmap(ctl, bitmap); |
|
|
|
return true; |
|
} |
|
|
|
/* |
|
* We prefer always to allocate from extent entries, both for clustered and |
|
* non-clustered allocation requests. So when attempting to add a new extent |
|
* entry, try to see if there's adjacent free space in bitmap entries, and if |
|
* there is, migrate that space from the bitmaps to the extent. |
|
* Like this we get better chances of satisfying space allocation requests |
|
* because we attempt to satisfy them based on a single cache entry, and never |
|
* on 2 or more entries - even if the entries represent a contiguous free space |
|
* region (e.g. 1 extent entry + 1 bitmap entry starting where the extent entry |
|
* ends). |
|
*/ |
|
static void steal_from_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *info, |
|
bool update_stat) |
|
{ |
|
/* |
|
* Only work with disconnected entries, as we can change their offset, |
|
* and must be extent entries. |
|
*/ |
|
ASSERT(!info->bitmap); |
|
ASSERT(RB_EMPTY_NODE(&info->offset_index)); |
|
|
|
if (ctl->total_bitmaps > 0) { |
|
bool stole_end; |
|
bool stole_front = false; |
|
|
|
stole_end = steal_from_bitmap_to_end(ctl, info, update_stat); |
|
if (ctl->total_bitmaps > 0) |
|
stole_front = steal_from_bitmap_to_front(ctl, info, |
|
update_stat); |
|
|
|
if (stole_end || stole_front) |
|
try_merge_free_space(ctl, info, update_stat); |
|
} |
|
} |
|
|
|
int __btrfs_add_free_space(struct btrfs_block_group *block_group, |
|
u64 offset, u64 bytes, |
|
enum btrfs_trim_state trim_state) |
|
{ |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *info; |
|
int ret = 0; |
|
u64 filter_bytes = bytes; |
|
|
|
ASSERT(!btrfs_is_zoned(fs_info)); |
|
|
|
info = kmem_cache_zalloc(btrfs_free_space_cachep, GFP_NOFS); |
|
if (!info) |
|
return -ENOMEM; |
|
|
|
info->offset = offset; |
|
info->bytes = bytes; |
|
info->trim_state = trim_state; |
|
RB_CLEAR_NODE(&info->offset_index); |
|
RB_CLEAR_NODE(&info->bytes_index); |
|
|
|
spin_lock(&ctl->tree_lock); |
|
|
|
if (try_merge_free_space(ctl, info, true)) |
|
goto link; |
|
|
|
/* |
|
* There was no extent directly to the left or right of this new |
|
* extent then we know we're going to have to allocate a new extent, so |
|
* before we do that see if we need to drop this into a bitmap |
|
*/ |
|
ret = insert_into_bitmap(ctl, info); |
|
if (ret < 0) { |
|
goto out; |
|
} else if (ret) { |
|
ret = 0; |
|
goto out; |
|
} |
|
link: |
|
/* |
|
* Only steal free space from adjacent bitmaps if we're sure we're not |
|
* going to add the new free space to existing bitmap entries - because |
|
* that would mean unnecessary work that would be reverted. Therefore |
|
* attempt to steal space from bitmaps if we're adding an extent entry. |
|
*/ |
|
steal_from_bitmap(ctl, info, true); |
|
|
|
filter_bytes = max(filter_bytes, info->bytes); |
|
|
|
ret = link_free_space(ctl, info); |
|
if (ret) |
|
kmem_cache_free(btrfs_free_space_cachep, info); |
|
out: |
|
btrfs_discard_update_discardable(block_group); |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
if (ret) { |
|
btrfs_crit(fs_info, "unable to add free space :%d", ret); |
|
ASSERT(ret != -EEXIST); |
|
} |
|
|
|
if (trim_state != BTRFS_TRIM_STATE_TRIMMED) { |
|
btrfs_discard_check_filter(block_group, filter_bytes); |
|
btrfs_discard_queue_work(&fs_info->discard_ctl, block_group); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int __btrfs_add_free_space_zoned(struct btrfs_block_group *block_group, |
|
u64 bytenr, u64 size, bool used) |
|
{ |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
u64 offset = bytenr - block_group->start; |
|
u64 to_free, to_unusable; |
|
const int bg_reclaim_threshold = READ_ONCE(fs_info->bg_reclaim_threshold); |
|
bool initial = (size == block_group->length); |
|
u64 reclaimable_unusable; |
|
|
|
WARN_ON(!initial && offset + size > block_group->zone_capacity); |
|
|
|
spin_lock(&ctl->tree_lock); |
|
if (!used) |
|
to_free = size; |
|
else if (initial) |
|
to_free = block_group->zone_capacity; |
|
else if (offset >= block_group->alloc_offset) |
|
to_free = size; |
|
else if (offset + size <= block_group->alloc_offset) |
|
to_free = 0; |
|
else |
|
to_free = offset + size - block_group->alloc_offset; |
|
to_unusable = size - to_free; |
|
|
|
ctl->free_space += to_free; |
|
/* |
|
* If the block group is read-only, we should account freed space into |
|
* bytes_readonly. |
|
*/ |
|
if (!block_group->ro) |
|
block_group->zone_unusable += to_unusable; |
|
spin_unlock(&ctl->tree_lock); |
|
if (!used) { |
|
spin_lock(&block_group->lock); |
|
block_group->alloc_offset -= size; |
|
spin_unlock(&block_group->lock); |
|
} |
|
|
|
reclaimable_unusable = block_group->zone_unusable - |
|
(block_group->length - block_group->zone_capacity); |
|
/* All the region is now unusable. Mark it as unused and reclaim */ |
|
if (block_group->zone_unusable == block_group->length) { |
|
btrfs_mark_bg_unused(block_group); |
|
} else if (bg_reclaim_threshold && |
|
reclaimable_unusable >= |
|
div_factor_fine(block_group->zone_capacity, |
|
bg_reclaim_threshold)) { |
|
btrfs_mark_bg_to_reclaim(block_group); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
int btrfs_add_free_space(struct btrfs_block_group *block_group, |
|
u64 bytenr, u64 size) |
|
{ |
|
enum btrfs_trim_state trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
|
|
if (btrfs_is_zoned(block_group->fs_info)) |
|
return __btrfs_add_free_space_zoned(block_group, bytenr, size, |
|
true); |
|
|
|
if (btrfs_test_opt(block_group->fs_info, DISCARD_SYNC)) |
|
trim_state = BTRFS_TRIM_STATE_TRIMMED; |
|
|
|
return __btrfs_add_free_space(block_group, bytenr, size, trim_state); |
|
} |
|
|
|
int btrfs_add_free_space_unused(struct btrfs_block_group *block_group, |
|
u64 bytenr, u64 size) |
|
{ |
|
if (btrfs_is_zoned(block_group->fs_info)) |
|
return __btrfs_add_free_space_zoned(block_group, bytenr, size, |
|
false); |
|
|
|
return btrfs_add_free_space(block_group, bytenr, size); |
|
} |
|
|
|
/* |
|
* This is a subtle distinction because when adding free space back in general, |
|
* we want it to be added as untrimmed for async. But in the case where we add |
|
* it on loading of a block group, we want to consider it trimmed. |
|
*/ |
|
int btrfs_add_free_space_async_trimmed(struct btrfs_block_group *block_group, |
|
u64 bytenr, u64 size) |
|
{ |
|
enum btrfs_trim_state trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
|
|
if (btrfs_is_zoned(block_group->fs_info)) |
|
return __btrfs_add_free_space_zoned(block_group, bytenr, size, |
|
true); |
|
|
|
if (btrfs_test_opt(block_group->fs_info, DISCARD_SYNC) || |
|
btrfs_test_opt(block_group->fs_info, DISCARD_ASYNC)) |
|
trim_state = BTRFS_TRIM_STATE_TRIMMED; |
|
|
|
return __btrfs_add_free_space(block_group, bytenr, size, trim_state); |
|
} |
|
|
|
int btrfs_remove_free_space(struct btrfs_block_group *block_group, |
|
u64 offset, u64 bytes) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *info; |
|
int ret; |
|
bool re_search = false; |
|
|
|
if (btrfs_is_zoned(block_group->fs_info)) { |
|
/* |
|
* This can happen with conventional zones when replaying log. |
|
* Since the allocation info of tree-log nodes are not recorded |
|
* to the extent-tree, calculate_alloc_pointer() failed to |
|
* advance the allocation pointer after last allocated tree log |
|
* node blocks. |
|
* |
|
* This function is called from |
|
* btrfs_pin_extent_for_log_replay() when replaying the log. |
|
* Advance the pointer not to overwrite the tree-log nodes. |
|
*/ |
|
if (block_group->start + block_group->alloc_offset < |
|
offset + bytes) { |
|
block_group->alloc_offset = |
|
offset + bytes - block_group->start; |
|
} |
|
return 0; |
|
} |
|
|
|
spin_lock(&ctl->tree_lock); |
|
|
|
again: |
|
ret = 0; |
|
if (!bytes) |
|
goto out_lock; |
|
|
|
info = tree_search_offset(ctl, offset, 0, 0); |
|
if (!info) { |
|
/* |
|
* oops didn't find an extent that matched the space we wanted |
|
* to remove, look for a bitmap instead |
|
*/ |
|
info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset), |
|
1, 0); |
|
if (!info) { |
|
/* |
|
* If we found a partial bit of our free space in a |
|
* bitmap but then couldn't find the other part this may |
|
* be a problem, so WARN about it. |
|
*/ |
|
WARN_ON(re_search); |
|
goto out_lock; |
|
} |
|
} |
|
|
|
re_search = false; |
|
if (!info->bitmap) { |
|
unlink_free_space(ctl, info, true); |
|
if (offset == info->offset) { |
|
u64 to_free = min(bytes, info->bytes); |
|
|
|
info->bytes -= to_free; |
|
info->offset += to_free; |
|
if (info->bytes) { |
|
ret = link_free_space(ctl, info); |
|
WARN_ON(ret); |
|
} else { |
|
kmem_cache_free(btrfs_free_space_cachep, info); |
|
} |
|
|
|
offset += to_free; |
|
bytes -= to_free; |
|
goto again; |
|
} else { |
|
u64 old_end = info->bytes + info->offset; |
|
|
|
info->bytes = offset - info->offset; |
|
ret = link_free_space(ctl, info); |
|
WARN_ON(ret); |
|
if (ret) |
|
goto out_lock; |
|
|
|
/* Not enough bytes in this entry to satisfy us */ |
|
if (old_end < offset + bytes) { |
|
bytes -= old_end - offset; |
|
offset = old_end; |
|
goto again; |
|
} else if (old_end == offset + bytes) { |
|
/* all done */ |
|
goto out_lock; |
|
} |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
ret = __btrfs_add_free_space(block_group, |
|
offset + bytes, |
|
old_end - (offset + bytes), |
|
info->trim_state); |
|
WARN_ON(ret); |
|
goto out; |
|
} |
|
} |
|
|
|
ret = remove_from_bitmap(ctl, info, &offset, &bytes); |
|
if (ret == -EAGAIN) { |
|
re_search = true; |
|
goto again; |
|
} |
|
out_lock: |
|
btrfs_discard_update_discardable(block_group); |
|
spin_unlock(&ctl->tree_lock); |
|
out: |
|
return ret; |
|
} |
|
|
|
void btrfs_dump_free_space(struct btrfs_block_group *block_group, |
|
u64 bytes) |
|
{ |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *info; |
|
struct rb_node *n; |
|
int count = 0; |
|
|
|
/* |
|
* Zoned btrfs does not use free space tree and cluster. Just print |
|
* out the free space after the allocation offset. |
|
*/ |
|
if (btrfs_is_zoned(fs_info)) { |
|
btrfs_info(fs_info, "free space %llu active %d", |
|
block_group->zone_capacity - block_group->alloc_offset, |
|
block_group->zone_is_active); |
|
return; |
|
} |
|
|
|
spin_lock(&ctl->tree_lock); |
|
for (n = rb_first(&ctl->free_space_offset); n; n = rb_next(n)) { |
|
info = rb_entry(n, struct btrfs_free_space, offset_index); |
|
if (info->bytes >= bytes && !block_group->ro) |
|
count++; |
|
btrfs_crit(fs_info, "entry offset %llu, bytes %llu, bitmap %s", |
|
info->offset, info->bytes, |
|
(info->bitmap) ? "yes" : "no"); |
|
} |
|
spin_unlock(&ctl->tree_lock); |
|
btrfs_info(fs_info, "block group has cluster?: %s", |
|
list_empty(&block_group->cluster_list) ? "no" : "yes"); |
|
btrfs_info(fs_info, |
|
"%d blocks of free space at or bigger than bytes is", count); |
|
} |
|
|
|
void btrfs_init_free_space_ctl(struct btrfs_block_group *block_group, |
|
struct btrfs_free_space_ctl *ctl) |
|
{ |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
|
|
spin_lock_init(&ctl->tree_lock); |
|
ctl->unit = fs_info->sectorsize; |
|
ctl->start = block_group->start; |
|
ctl->block_group = block_group; |
|
ctl->op = &free_space_op; |
|
ctl->free_space_bytes = RB_ROOT_CACHED; |
|
INIT_LIST_HEAD(&ctl->trimming_ranges); |
|
mutex_init(&ctl->cache_writeout_mutex); |
|
|
|
/* |
|
* we only want to have 32k of ram per block group for keeping |
|
* track of free space, and if we pass 1/2 of that we want to |
|
* start converting things over to using bitmaps |
|
*/ |
|
ctl->extents_thresh = (SZ_32K / 2) / sizeof(struct btrfs_free_space); |
|
} |
|
|
|
/* |
|
* for a given cluster, put all of its extents back into the free |
|
* space cache. If the block group passed doesn't match the block group |
|
* pointed to by the cluster, someone else raced in and freed the |
|
* cluster already. In that case, we just return without changing anything |
|
*/ |
|
static void __btrfs_return_cluster_to_free_space( |
|
struct btrfs_block_group *block_group, |
|
struct btrfs_free_cluster *cluster) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *entry; |
|
struct rb_node *node; |
|
|
|
spin_lock(&cluster->lock); |
|
if (cluster->block_group != block_group) { |
|
spin_unlock(&cluster->lock); |
|
return; |
|
} |
|
|
|
cluster->block_group = NULL; |
|
cluster->window_start = 0; |
|
list_del_init(&cluster->block_group_list); |
|
|
|
node = rb_first(&cluster->root); |
|
while (node) { |
|
bool bitmap; |
|
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index); |
|
node = rb_next(&entry->offset_index); |
|
rb_erase(&entry->offset_index, &cluster->root); |
|
RB_CLEAR_NODE(&entry->offset_index); |
|
|
|
bitmap = (entry->bitmap != NULL); |
|
if (!bitmap) { |
|
/* Merging treats extents as if they were new */ |
|
if (!btrfs_free_space_trimmed(entry)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR]--; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] -= |
|
entry->bytes; |
|
} |
|
|
|
try_merge_free_space(ctl, entry, false); |
|
steal_from_bitmap(ctl, entry, false); |
|
|
|
/* As we insert directly, update these statistics */ |
|
if (!btrfs_free_space_trimmed(entry)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR]++; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] += |
|
entry->bytes; |
|
} |
|
} |
|
tree_insert_offset(&ctl->free_space_offset, |
|
entry->offset, &entry->offset_index, bitmap); |
|
rb_add_cached(&entry->bytes_index, &ctl->free_space_bytes, |
|
entry_less); |
|
} |
|
cluster->root = RB_ROOT; |
|
spin_unlock(&cluster->lock); |
|
btrfs_put_block_group(block_group); |
|
} |
|
|
|
static void __btrfs_remove_free_space_cache_locked( |
|
struct btrfs_free_space_ctl *ctl) |
|
{ |
|
struct btrfs_free_space *info; |
|
struct rb_node *node; |
|
|
|
while ((node = rb_last(&ctl->free_space_offset)) != NULL) { |
|
info = rb_entry(node, struct btrfs_free_space, offset_index); |
|
if (!info->bitmap) { |
|
unlink_free_space(ctl, info, true); |
|
kmem_cache_free(btrfs_free_space_cachep, info); |
|
} else { |
|
free_bitmap(ctl, info); |
|
} |
|
|
|
cond_resched_lock(&ctl->tree_lock); |
|
} |
|
} |
|
|
|
void __btrfs_remove_free_space_cache(struct btrfs_free_space_ctl *ctl) |
|
{ |
|
spin_lock(&ctl->tree_lock); |
|
__btrfs_remove_free_space_cache_locked(ctl); |
|
if (ctl->block_group) |
|
btrfs_discard_update_discardable(ctl->block_group); |
|
spin_unlock(&ctl->tree_lock); |
|
} |
|
|
|
void btrfs_remove_free_space_cache(struct btrfs_block_group *block_group) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_cluster *cluster; |
|
struct list_head *head; |
|
|
|
spin_lock(&ctl->tree_lock); |
|
while ((head = block_group->cluster_list.next) != |
|
&block_group->cluster_list) { |
|
cluster = list_entry(head, struct btrfs_free_cluster, |
|
block_group_list); |
|
|
|
WARN_ON(cluster->block_group != block_group); |
|
__btrfs_return_cluster_to_free_space(block_group, cluster); |
|
|
|
cond_resched_lock(&ctl->tree_lock); |
|
} |
|
__btrfs_remove_free_space_cache_locked(ctl); |
|
btrfs_discard_update_discardable(block_group); |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
} |
|
|
|
/** |
|
* btrfs_is_free_space_trimmed - see if everything is trimmed |
|
* @block_group: block_group of interest |
|
* |
|
* Walk @block_group's free space rb_tree to determine if everything is trimmed. |
|
*/ |
|
bool btrfs_is_free_space_trimmed(struct btrfs_block_group *block_group) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *info; |
|
struct rb_node *node; |
|
bool ret = true; |
|
|
|
spin_lock(&ctl->tree_lock); |
|
node = rb_first(&ctl->free_space_offset); |
|
|
|
while (node) { |
|
info = rb_entry(node, struct btrfs_free_space, offset_index); |
|
|
|
if (!btrfs_free_space_trimmed(info)) { |
|
ret = false; |
|
break; |
|
} |
|
|
|
node = rb_next(node); |
|
} |
|
|
|
spin_unlock(&ctl->tree_lock); |
|
return ret; |
|
} |
|
|
|
u64 btrfs_find_space_for_alloc(struct btrfs_block_group *block_group, |
|
u64 offset, u64 bytes, u64 empty_size, |
|
u64 *max_extent_size) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_discard_ctl *discard_ctl = |
|
&block_group->fs_info->discard_ctl; |
|
struct btrfs_free_space *entry = NULL; |
|
u64 bytes_search = bytes + empty_size; |
|
u64 ret = 0; |
|
u64 align_gap = 0; |
|
u64 align_gap_len = 0; |
|
enum btrfs_trim_state align_gap_trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
bool use_bytes_index = (offset == block_group->start); |
|
|
|
ASSERT(!btrfs_is_zoned(block_group->fs_info)); |
|
|
|
spin_lock(&ctl->tree_lock); |
|
entry = find_free_space(ctl, &offset, &bytes_search, |
|
block_group->full_stripe_len, max_extent_size, |
|
use_bytes_index); |
|
if (!entry) |
|
goto out; |
|
|
|
ret = offset; |
|
if (entry->bitmap) { |
|
bitmap_clear_bits(ctl, entry, offset, bytes, true); |
|
|
|
if (!btrfs_free_space_trimmed(entry)) |
|
atomic64_add(bytes, &discard_ctl->discard_bytes_saved); |
|
|
|
if (!entry->bytes) |
|
free_bitmap(ctl, entry); |
|
} else { |
|
unlink_free_space(ctl, entry, true); |
|
align_gap_len = offset - entry->offset; |
|
align_gap = entry->offset; |
|
align_gap_trim_state = entry->trim_state; |
|
|
|
if (!btrfs_free_space_trimmed(entry)) |
|
atomic64_add(bytes, &discard_ctl->discard_bytes_saved); |
|
|
|
entry->offset = offset + bytes; |
|
WARN_ON(entry->bytes < bytes + align_gap_len); |
|
|
|
entry->bytes -= bytes + align_gap_len; |
|
if (!entry->bytes) |
|
kmem_cache_free(btrfs_free_space_cachep, entry); |
|
else |
|
link_free_space(ctl, entry); |
|
} |
|
out: |
|
btrfs_discard_update_discardable(block_group); |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
if (align_gap_len) |
|
__btrfs_add_free_space(block_group, align_gap, align_gap_len, |
|
align_gap_trim_state); |
|
return ret; |
|
} |
|
|
|
/* |
|
* given a cluster, put all of its extents back into the free space |
|
* cache. If a block group is passed, this function will only free |
|
* a cluster that belongs to the passed block group. |
|
* |
|
* Otherwise, it'll get a reference on the block group pointed to by the |
|
* cluster and remove the cluster from it. |
|
*/ |
|
void btrfs_return_cluster_to_free_space( |
|
struct btrfs_block_group *block_group, |
|
struct btrfs_free_cluster *cluster) |
|
{ |
|
struct btrfs_free_space_ctl *ctl; |
|
|
|
/* first, get a safe pointer to the block group */ |
|
spin_lock(&cluster->lock); |
|
if (!block_group) { |
|
block_group = cluster->block_group; |
|
if (!block_group) { |
|
spin_unlock(&cluster->lock); |
|
return; |
|
} |
|
} else if (cluster->block_group != block_group) { |
|
/* someone else has already freed it don't redo their work */ |
|
spin_unlock(&cluster->lock); |
|
return; |
|
} |
|
btrfs_get_block_group(block_group); |
|
spin_unlock(&cluster->lock); |
|
|
|
ctl = block_group->free_space_ctl; |
|
|
|
/* now return any extents the cluster had on it */ |
|
spin_lock(&ctl->tree_lock); |
|
__btrfs_return_cluster_to_free_space(block_group, cluster); |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
btrfs_discard_queue_work(&block_group->fs_info->discard_ctl, block_group); |
|
|
|
/* finally drop our ref */ |
|
btrfs_put_block_group(block_group); |
|
} |
|
|
|
static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group *block_group, |
|
struct btrfs_free_cluster *cluster, |
|
struct btrfs_free_space *entry, |
|
u64 bytes, u64 min_start, |
|
u64 *max_extent_size) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
int err; |
|
u64 search_start = cluster->window_start; |
|
u64 search_bytes = bytes; |
|
u64 ret = 0; |
|
|
|
search_start = min_start; |
|
search_bytes = bytes; |
|
|
|
err = search_bitmap(ctl, entry, &search_start, &search_bytes, true); |
|
if (err) { |
|
*max_extent_size = max(get_max_extent_size(entry), |
|
*max_extent_size); |
|
return 0; |
|
} |
|
|
|
ret = search_start; |
|
bitmap_clear_bits(ctl, entry, ret, bytes, false); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* given a cluster, try to allocate 'bytes' from it, returns 0 |
|
* if it couldn't find anything suitably large, or a logical disk offset |
|
* if things worked out |
|
*/ |
|
u64 btrfs_alloc_from_cluster(struct btrfs_block_group *block_group, |
|
struct btrfs_free_cluster *cluster, u64 bytes, |
|
u64 min_start, u64 *max_extent_size) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_discard_ctl *discard_ctl = |
|
&block_group->fs_info->discard_ctl; |
|
struct btrfs_free_space *entry = NULL; |
|
struct rb_node *node; |
|
u64 ret = 0; |
|
|
|
ASSERT(!btrfs_is_zoned(block_group->fs_info)); |
|
|
|
spin_lock(&cluster->lock); |
|
if (bytes > cluster->max_size) |
|
goto out; |
|
|
|
if (cluster->block_group != block_group) |
|
goto out; |
|
|
|
node = rb_first(&cluster->root); |
|
if (!node) |
|
goto out; |
|
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index); |
|
while (1) { |
|
if (entry->bytes < bytes) |
|
*max_extent_size = max(get_max_extent_size(entry), |
|
*max_extent_size); |
|
|
|
if (entry->bytes < bytes || |
|
(!entry->bitmap && entry->offset < min_start)) { |
|
node = rb_next(&entry->offset_index); |
|
if (!node) |
|
break; |
|
entry = rb_entry(node, struct btrfs_free_space, |
|
offset_index); |
|
continue; |
|
} |
|
|
|
if (entry->bitmap) { |
|
ret = btrfs_alloc_from_bitmap(block_group, |
|
cluster, entry, bytes, |
|
cluster->window_start, |
|
max_extent_size); |
|
if (ret == 0) { |
|
node = rb_next(&entry->offset_index); |
|
if (!node) |
|
break; |
|
entry = rb_entry(node, struct btrfs_free_space, |
|
offset_index); |
|
continue; |
|
} |
|
cluster->window_start += bytes; |
|
} else { |
|
ret = entry->offset; |
|
|
|
entry->offset += bytes; |
|
entry->bytes -= bytes; |
|
} |
|
|
|
break; |
|
} |
|
out: |
|
spin_unlock(&cluster->lock); |
|
|
|
if (!ret) |
|
return 0; |
|
|
|
spin_lock(&ctl->tree_lock); |
|
|
|
if (!btrfs_free_space_trimmed(entry)) |
|
atomic64_add(bytes, &discard_ctl->discard_bytes_saved); |
|
|
|
ctl->free_space -= bytes; |
|
if (!entry->bitmap && !btrfs_free_space_trimmed(entry)) |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] -= bytes; |
|
|
|
spin_lock(&cluster->lock); |
|
if (entry->bytes == 0) { |
|
rb_erase(&entry->offset_index, &cluster->root); |
|
ctl->free_extents--; |
|
if (entry->bitmap) { |
|
kmem_cache_free(btrfs_free_space_bitmap_cachep, |
|
entry->bitmap); |
|
ctl->total_bitmaps--; |
|
recalculate_thresholds(ctl); |
|
} else if (!btrfs_free_space_trimmed(entry)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR]--; |
|
} |
|
kmem_cache_free(btrfs_free_space_cachep, entry); |
|
} |
|
|
|
spin_unlock(&cluster->lock); |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
return ret; |
|
} |
|
|
|
static int btrfs_bitmap_cluster(struct btrfs_block_group *block_group, |
|
struct btrfs_free_space *entry, |
|
struct btrfs_free_cluster *cluster, |
|
u64 offset, u64 bytes, |
|
u64 cont1_bytes, u64 min_bytes) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
unsigned long next_zero; |
|
unsigned long i; |
|
unsigned long want_bits; |
|
unsigned long min_bits; |
|
unsigned long found_bits; |
|
unsigned long max_bits = 0; |
|
unsigned long start = 0; |
|
unsigned long total_found = 0; |
|
int ret; |
|
|
|
i = offset_to_bit(entry->offset, ctl->unit, |
|
max_t(u64, offset, entry->offset)); |
|
want_bits = bytes_to_bits(bytes, ctl->unit); |
|
min_bits = bytes_to_bits(min_bytes, ctl->unit); |
|
|
|
/* |
|
* Don't bother looking for a cluster in this bitmap if it's heavily |
|
* fragmented. |
|
*/ |
|
if (entry->max_extent_size && |
|
entry->max_extent_size < cont1_bytes) |
|
return -ENOSPC; |
|
again: |
|
found_bits = 0; |
|
for_each_set_bit_from(i, entry->bitmap, BITS_PER_BITMAP) { |
|
next_zero = find_next_zero_bit(entry->bitmap, |
|
BITS_PER_BITMAP, i); |
|
if (next_zero - i >= min_bits) { |
|
found_bits = next_zero - i; |
|
if (found_bits > max_bits) |
|
max_bits = found_bits; |
|
break; |
|
} |
|
if (next_zero - i > max_bits) |
|
max_bits = next_zero - i; |
|
i = next_zero; |
|
} |
|
|
|
if (!found_bits) { |
|
entry->max_extent_size = (u64)max_bits * ctl->unit; |
|
return -ENOSPC; |
|
} |
|
|
|
if (!total_found) { |
|
start = i; |
|
cluster->max_size = 0; |
|
} |
|
|
|
total_found += found_bits; |
|
|
|
if (cluster->max_size < found_bits * ctl->unit) |
|
cluster->max_size = found_bits * ctl->unit; |
|
|
|
if (total_found < want_bits || cluster->max_size < cont1_bytes) { |
|
i = next_zero + 1; |
|
goto again; |
|
} |
|
|
|
cluster->window_start = start * ctl->unit + entry->offset; |
|
rb_erase(&entry->offset_index, &ctl->free_space_offset); |
|
rb_erase_cached(&entry->bytes_index, &ctl->free_space_bytes); |
|
|
|
/* |
|
* We need to know if we're currently on the normal space index when we |
|
* manipulate the bitmap so that we know we need to remove and re-insert |
|
* it into the space_index tree. Clear the bytes_index node here so the |
|
* bitmap manipulation helpers know not to mess with the space_index |
|
* until this bitmap entry is added back into the normal cache. |
|
*/ |
|
RB_CLEAR_NODE(&entry->bytes_index); |
|
|
|
ret = tree_insert_offset(&cluster->root, entry->offset, |
|
&entry->offset_index, 1); |
|
ASSERT(!ret); /* -EEXIST; Logic error */ |
|
|
|
trace_btrfs_setup_cluster(block_group, cluster, |
|
total_found * ctl->unit, 1); |
|
return 0; |
|
} |
|
|
|
/* |
|
* This searches the block group for just extents to fill the cluster with. |
|
* Try to find a cluster with at least bytes total bytes, at least one |
|
* extent of cont1_bytes, and other clusters of at least min_bytes. |
|
*/ |
|
static noinline int |
|
setup_cluster_no_bitmap(struct btrfs_block_group *block_group, |
|
struct btrfs_free_cluster *cluster, |
|
struct list_head *bitmaps, u64 offset, u64 bytes, |
|
u64 cont1_bytes, u64 min_bytes) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *first = NULL; |
|
struct btrfs_free_space *entry = NULL; |
|
struct btrfs_free_space *last; |
|
struct rb_node *node; |
|
u64 window_free; |
|
u64 max_extent; |
|
u64 total_size = 0; |
|
|
|
entry = tree_search_offset(ctl, offset, 0, 1); |
|
if (!entry) |
|
return -ENOSPC; |
|
|
|
/* |
|
* We don't want bitmaps, so just move along until we find a normal |
|
* extent entry. |
|
*/ |
|
while (entry->bitmap || entry->bytes < min_bytes) { |
|
if (entry->bitmap && list_empty(&entry->list)) |
|
list_add_tail(&entry->list, bitmaps); |
|
node = rb_next(&entry->offset_index); |
|
if (!node) |
|
return -ENOSPC; |
|
entry = rb_entry(node, struct btrfs_free_space, offset_index); |
|
} |
|
|
|
window_free = entry->bytes; |
|
max_extent = entry->bytes; |
|
first = entry; |
|
last = entry; |
|
|
|
for (node = rb_next(&entry->offset_index); node; |
|
node = rb_next(&entry->offset_index)) { |
|
entry = rb_entry(node, struct btrfs_free_space, offset_index); |
|
|
|
if (entry->bitmap) { |
|
if (list_empty(&entry->list)) |
|
list_add_tail(&entry->list, bitmaps); |
|
continue; |
|
} |
|
|
|
if (entry->bytes < min_bytes) |
|
continue; |
|
|
|
last = entry; |
|
window_free += entry->bytes; |
|
if (entry->bytes > max_extent) |
|
max_extent = entry->bytes; |
|
} |
|
|
|
if (window_free < bytes || max_extent < cont1_bytes) |
|
return -ENOSPC; |
|
|
|
cluster->window_start = first->offset; |
|
|
|
node = &first->offset_index; |
|
|
|
/* |
|
* now we've found our entries, pull them out of the free space |
|
* cache and put them into the cluster rbtree |
|
*/ |
|
do { |
|
int ret; |
|
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index); |
|
node = rb_next(&entry->offset_index); |
|
if (entry->bitmap || entry->bytes < min_bytes) |
|
continue; |
|
|
|
rb_erase(&entry->offset_index, &ctl->free_space_offset); |
|
rb_erase_cached(&entry->bytes_index, &ctl->free_space_bytes); |
|
ret = tree_insert_offset(&cluster->root, entry->offset, |
|
&entry->offset_index, 0); |
|
total_size += entry->bytes; |
|
ASSERT(!ret); /* -EEXIST; Logic error */ |
|
} while (node && entry != last); |
|
|
|
cluster->max_size = max_extent; |
|
trace_btrfs_setup_cluster(block_group, cluster, total_size, 0); |
|
return 0; |
|
} |
|
|
|
/* |
|
* This specifically looks for bitmaps that may work in the cluster, we assume |
|
* that we have already failed to find extents that will work. |
|
*/ |
|
static noinline int |
|
setup_cluster_bitmap(struct btrfs_block_group *block_group, |
|
struct btrfs_free_cluster *cluster, |
|
struct list_head *bitmaps, u64 offset, u64 bytes, |
|
u64 cont1_bytes, u64 min_bytes) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *entry = NULL; |
|
int ret = -ENOSPC; |
|
u64 bitmap_offset = offset_to_bitmap(ctl, offset); |
|
|
|
if (ctl->total_bitmaps == 0) |
|
return -ENOSPC; |
|
|
|
/* |
|
* The bitmap that covers offset won't be in the list unless offset |
|
* is just its start offset. |
|
*/ |
|
if (!list_empty(bitmaps)) |
|
entry = list_first_entry(bitmaps, struct btrfs_free_space, list); |
|
|
|
if (!entry || entry->offset != bitmap_offset) { |
|
entry = tree_search_offset(ctl, bitmap_offset, 1, 0); |
|
if (entry && list_empty(&entry->list)) |
|
list_add(&entry->list, bitmaps); |
|
} |
|
|
|
list_for_each_entry(entry, bitmaps, list) { |
|
if (entry->bytes < bytes) |
|
continue; |
|
ret = btrfs_bitmap_cluster(block_group, entry, cluster, offset, |
|
bytes, cont1_bytes, min_bytes); |
|
if (!ret) |
|
return 0; |
|
} |
|
|
|
/* |
|
* The bitmaps list has all the bitmaps that record free space |
|
* starting after offset, so no more search is required. |
|
*/ |
|
return -ENOSPC; |
|
} |
|
|
|
/* |
|
* here we try to find a cluster of blocks in a block group. The goal |
|
* is to find at least bytes+empty_size. |
|
* We might not find them all in one contiguous area. |
|
* |
|
* returns zero and sets up cluster if things worked out, otherwise |
|
* it returns -enospc |
|
*/ |
|
int btrfs_find_space_cluster(struct btrfs_block_group *block_group, |
|
struct btrfs_free_cluster *cluster, |
|
u64 offset, u64 bytes, u64 empty_size) |
|
{ |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *entry, *tmp; |
|
LIST_HEAD(bitmaps); |
|
u64 min_bytes; |
|
u64 cont1_bytes; |
|
int ret; |
|
|
|
/* |
|
* Choose the minimum extent size we'll require for this |
|
* cluster. For SSD_SPREAD, don't allow any fragmentation. |
|
* For metadata, allow allocates with smaller extents. For |
|
* data, keep it dense. |
|
*/ |
|
if (btrfs_test_opt(fs_info, SSD_SPREAD)) { |
|
cont1_bytes = min_bytes = bytes + empty_size; |
|
} else if (block_group->flags & BTRFS_BLOCK_GROUP_METADATA) { |
|
cont1_bytes = bytes; |
|
min_bytes = fs_info->sectorsize; |
|
} else { |
|
cont1_bytes = max(bytes, (bytes + empty_size) >> 2); |
|
min_bytes = fs_info->sectorsize; |
|
} |
|
|
|
spin_lock(&ctl->tree_lock); |
|
|
|
/* |
|
* If we know we don't have enough space to make a cluster don't even |
|
* bother doing all the work to try and find one. |
|
*/ |
|
if (ctl->free_space < bytes) { |
|
spin_unlock(&ctl->tree_lock); |
|
return -ENOSPC; |
|
} |
|
|
|
spin_lock(&cluster->lock); |
|
|
|
/* someone already found a cluster, hooray */ |
|
if (cluster->block_group) { |
|
ret = 0; |
|
goto out; |
|
} |
|
|
|
trace_btrfs_find_cluster(block_group, offset, bytes, empty_size, |
|
min_bytes); |
|
|
|
ret = setup_cluster_no_bitmap(block_group, cluster, &bitmaps, offset, |
|
bytes + empty_size, |
|
cont1_bytes, min_bytes); |
|
if (ret) |
|
ret = setup_cluster_bitmap(block_group, cluster, &bitmaps, |
|
offset, bytes + empty_size, |
|
cont1_bytes, min_bytes); |
|
|
|
/* Clear our temporary list */ |
|
list_for_each_entry_safe(entry, tmp, &bitmaps, list) |
|
list_del_init(&entry->list); |
|
|
|
if (!ret) { |
|
btrfs_get_block_group(block_group); |
|
list_add_tail(&cluster->block_group_list, |
|
&block_group->cluster_list); |
|
cluster->block_group = block_group; |
|
} else { |
|
trace_btrfs_failed_cluster_setup(block_group); |
|
} |
|
out: |
|
spin_unlock(&cluster->lock); |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* simple code to zero out a cluster |
|
*/ |
|
void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster) |
|
{ |
|
spin_lock_init(&cluster->lock); |
|
spin_lock_init(&cluster->refill_lock); |
|
cluster->root = RB_ROOT; |
|
cluster->max_size = 0; |
|
cluster->fragmented = false; |
|
INIT_LIST_HEAD(&cluster->block_group_list); |
|
cluster->block_group = NULL; |
|
} |
|
|
|
static int do_trimming(struct btrfs_block_group *block_group, |
|
u64 *total_trimmed, u64 start, u64 bytes, |
|
u64 reserved_start, u64 reserved_bytes, |
|
enum btrfs_trim_state reserved_trim_state, |
|
struct btrfs_trim_range *trim_entry) |
|
{ |
|
struct btrfs_space_info *space_info = block_group->space_info; |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
int ret; |
|
int update = 0; |
|
const u64 end = start + bytes; |
|
const u64 reserved_end = reserved_start + reserved_bytes; |
|
enum btrfs_trim_state trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
u64 trimmed = 0; |
|
|
|
spin_lock(&space_info->lock); |
|
spin_lock(&block_group->lock); |
|
if (!block_group->ro) { |
|
block_group->reserved += reserved_bytes; |
|
space_info->bytes_reserved += reserved_bytes; |
|
update = 1; |
|
} |
|
spin_unlock(&block_group->lock); |
|
spin_unlock(&space_info->lock); |
|
|
|
ret = btrfs_discard_extent(fs_info, start, bytes, &trimmed); |
|
if (!ret) { |
|
*total_trimmed += trimmed; |
|
trim_state = BTRFS_TRIM_STATE_TRIMMED; |
|
} |
|
|
|
mutex_lock(&ctl->cache_writeout_mutex); |
|
if (reserved_start < start) |
|
__btrfs_add_free_space(block_group, reserved_start, |
|
start - reserved_start, |
|
reserved_trim_state); |
|
if (start + bytes < reserved_start + reserved_bytes) |
|
__btrfs_add_free_space(block_group, end, reserved_end - end, |
|
reserved_trim_state); |
|
__btrfs_add_free_space(block_group, start, bytes, trim_state); |
|
list_del(&trim_entry->list); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
|
|
if (update) { |
|
spin_lock(&space_info->lock); |
|
spin_lock(&block_group->lock); |
|
if (block_group->ro) |
|
space_info->bytes_readonly += reserved_bytes; |
|
block_group->reserved -= reserved_bytes; |
|
space_info->bytes_reserved -= reserved_bytes; |
|
spin_unlock(&block_group->lock); |
|
spin_unlock(&space_info->lock); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* If @async is set, then we will trim 1 region and return. |
|
*/ |
|
static int trim_no_bitmap(struct btrfs_block_group *block_group, |
|
u64 *total_trimmed, u64 start, u64 end, u64 minlen, |
|
bool async) |
|
{ |
|
struct btrfs_discard_ctl *discard_ctl = |
|
&block_group->fs_info->discard_ctl; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *entry; |
|
struct rb_node *node; |
|
int ret = 0; |
|
u64 extent_start; |
|
u64 extent_bytes; |
|
enum btrfs_trim_state extent_trim_state; |
|
u64 bytes; |
|
const u64 max_discard_size = READ_ONCE(discard_ctl->max_discard_size); |
|
|
|
while (start < end) { |
|
struct btrfs_trim_range trim_entry; |
|
|
|
mutex_lock(&ctl->cache_writeout_mutex); |
|
spin_lock(&ctl->tree_lock); |
|
|
|
if (ctl->free_space < minlen) |
|
goto out_unlock; |
|
|
|
entry = tree_search_offset(ctl, start, 0, 1); |
|
if (!entry) |
|
goto out_unlock; |
|
|
|
/* Skip bitmaps and if async, already trimmed entries */ |
|
while (entry->bitmap || |
|
(async && btrfs_free_space_trimmed(entry))) { |
|
node = rb_next(&entry->offset_index); |
|
if (!node) |
|
goto out_unlock; |
|
entry = rb_entry(node, struct btrfs_free_space, |
|
offset_index); |
|
} |
|
|
|
if (entry->offset >= end) |
|
goto out_unlock; |
|
|
|
extent_start = entry->offset; |
|
extent_bytes = entry->bytes; |
|
extent_trim_state = entry->trim_state; |
|
if (async) { |
|
start = entry->offset; |
|
bytes = entry->bytes; |
|
if (bytes < minlen) { |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
goto next; |
|
} |
|
unlink_free_space(ctl, entry, true); |
|
/* |
|
* Let bytes = BTRFS_MAX_DISCARD_SIZE + X. |
|
* If X < BTRFS_ASYNC_DISCARD_MIN_FILTER, we won't trim |
|
* X when we come back around. So trim it now. |
|
*/ |
|
if (max_discard_size && |
|
bytes >= (max_discard_size + |
|
BTRFS_ASYNC_DISCARD_MIN_FILTER)) { |
|
bytes = max_discard_size; |
|
extent_bytes = max_discard_size; |
|
entry->offset += max_discard_size; |
|
entry->bytes -= max_discard_size; |
|
link_free_space(ctl, entry); |
|
} else { |
|
kmem_cache_free(btrfs_free_space_cachep, entry); |
|
} |
|
} else { |
|
start = max(start, extent_start); |
|
bytes = min(extent_start + extent_bytes, end) - start; |
|
if (bytes < minlen) { |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
goto next; |
|
} |
|
|
|
unlink_free_space(ctl, entry, true); |
|
kmem_cache_free(btrfs_free_space_cachep, entry); |
|
} |
|
|
|
spin_unlock(&ctl->tree_lock); |
|
trim_entry.start = extent_start; |
|
trim_entry.bytes = extent_bytes; |
|
list_add_tail(&trim_entry.list, &ctl->trimming_ranges); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
|
|
ret = do_trimming(block_group, total_trimmed, start, bytes, |
|
extent_start, extent_bytes, extent_trim_state, |
|
&trim_entry); |
|
if (ret) { |
|
block_group->discard_cursor = start + bytes; |
|
break; |
|
} |
|
next: |
|
start += bytes; |
|
block_group->discard_cursor = start; |
|
if (async && *total_trimmed) |
|
break; |
|
|
|
if (fatal_signal_pending(current)) { |
|
ret = -ERESTARTSYS; |
|
break; |
|
} |
|
|
|
cond_resched(); |
|
} |
|
|
|
return ret; |
|
|
|
out_unlock: |
|
block_group->discard_cursor = btrfs_block_group_end(block_group); |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* If we break out of trimming a bitmap prematurely, we should reset the |
|
* trimming bit. In a rather contrieved case, it's possible to race here so |
|
* reset the state to BTRFS_TRIM_STATE_UNTRIMMED. |
|
* |
|
* start = start of bitmap |
|
* end = near end of bitmap |
|
* |
|
* Thread 1: Thread 2: |
|
* trim_bitmaps(start) |
|
* trim_bitmaps(end) |
|
* end_trimming_bitmap() |
|
* reset_trimming_bitmap() |
|
*/ |
|
static void reset_trimming_bitmap(struct btrfs_free_space_ctl *ctl, u64 offset) |
|
{ |
|
struct btrfs_free_space *entry; |
|
|
|
spin_lock(&ctl->tree_lock); |
|
entry = tree_search_offset(ctl, offset, 1, 0); |
|
if (entry) { |
|
if (btrfs_free_space_trimmed(entry)) { |
|
ctl->discardable_extents[BTRFS_STAT_CURR] += |
|
entry->bitmap_extents; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] += entry->bytes; |
|
} |
|
entry->trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
} |
|
|
|
spin_unlock(&ctl->tree_lock); |
|
} |
|
|
|
static void end_trimming_bitmap(struct btrfs_free_space_ctl *ctl, |
|
struct btrfs_free_space *entry) |
|
{ |
|
if (btrfs_free_space_trimming_bitmap(entry)) { |
|
entry->trim_state = BTRFS_TRIM_STATE_TRIMMED; |
|
ctl->discardable_extents[BTRFS_STAT_CURR] -= |
|
entry->bitmap_extents; |
|
ctl->discardable_bytes[BTRFS_STAT_CURR] -= entry->bytes; |
|
} |
|
} |
|
|
|
/* |
|
* If @async is set, then we will trim 1 region and return. |
|
*/ |
|
static int trim_bitmaps(struct btrfs_block_group *block_group, |
|
u64 *total_trimmed, u64 start, u64 end, u64 minlen, |
|
u64 maxlen, bool async) |
|
{ |
|
struct btrfs_discard_ctl *discard_ctl = |
|
&block_group->fs_info->discard_ctl; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
struct btrfs_free_space *entry; |
|
int ret = 0; |
|
int ret2; |
|
u64 bytes; |
|
u64 offset = offset_to_bitmap(ctl, start); |
|
const u64 max_discard_size = READ_ONCE(discard_ctl->max_discard_size); |
|
|
|
while (offset < end) { |
|
bool next_bitmap = false; |
|
struct btrfs_trim_range trim_entry; |
|
|
|
mutex_lock(&ctl->cache_writeout_mutex); |
|
spin_lock(&ctl->tree_lock); |
|
|
|
if (ctl->free_space < minlen) { |
|
block_group->discard_cursor = |
|
btrfs_block_group_end(block_group); |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
break; |
|
} |
|
|
|
entry = tree_search_offset(ctl, offset, 1, 0); |
|
/* |
|
* Bitmaps are marked trimmed lossily now to prevent constant |
|
* discarding of the same bitmap (the reason why we are bound |
|
* by the filters). So, retrim the block group bitmaps when we |
|
* are preparing to punt to the unused_bgs list. This uses |
|
* @minlen to determine if we are in BTRFS_DISCARD_INDEX_UNUSED |
|
* which is the only discard index which sets minlen to 0. |
|
*/ |
|
if (!entry || (async && minlen && start == offset && |
|
btrfs_free_space_trimmed(entry))) { |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
next_bitmap = true; |
|
goto next; |
|
} |
|
|
|
/* |
|
* Async discard bitmap trimming begins at by setting the start |
|
* to be key.objectid and the offset_to_bitmap() aligns to the |
|
* start of the bitmap. This lets us know we are fully |
|
* scanning the bitmap rather than only some portion of it. |
|
*/ |
|
if (start == offset) |
|
entry->trim_state = BTRFS_TRIM_STATE_TRIMMING; |
|
|
|
bytes = minlen; |
|
ret2 = search_bitmap(ctl, entry, &start, &bytes, false); |
|
if (ret2 || start >= end) { |
|
/* |
|
* We lossily consider a bitmap trimmed if we only skip |
|
* over regions <= BTRFS_ASYNC_DISCARD_MIN_FILTER. |
|
*/ |
|
if (ret2 && minlen <= BTRFS_ASYNC_DISCARD_MIN_FILTER) |
|
end_trimming_bitmap(ctl, entry); |
|
else |
|
entry->trim_state = BTRFS_TRIM_STATE_UNTRIMMED; |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
next_bitmap = true; |
|
goto next; |
|
} |
|
|
|
/* |
|
* We already trimmed a region, but are using the locking above |
|
* to reset the trim_state. |
|
*/ |
|
if (async && *total_trimmed) { |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
goto out; |
|
} |
|
|
|
bytes = min(bytes, end - start); |
|
if (bytes < minlen || (async && maxlen && bytes > maxlen)) { |
|
spin_unlock(&ctl->tree_lock); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
goto next; |
|
} |
|
|
|
/* |
|
* Let bytes = BTRFS_MAX_DISCARD_SIZE + X. |
|
* If X < @minlen, we won't trim X when we come back around. |
|
* So trim it now. We differ here from trimming extents as we |
|
* don't keep individual state per bit. |
|
*/ |
|
if (async && |
|
max_discard_size && |
|
bytes > (max_discard_size + minlen)) |
|
bytes = max_discard_size; |
|
|
|
bitmap_clear_bits(ctl, entry, start, bytes, true); |
|
if (entry->bytes == 0) |
|
free_bitmap(ctl, entry); |
|
|
|
spin_unlock(&ctl->tree_lock); |
|
trim_entry.start = start; |
|
trim_entry.bytes = bytes; |
|
list_add_tail(&trim_entry.list, &ctl->trimming_ranges); |
|
mutex_unlock(&ctl->cache_writeout_mutex); |
|
|
|
ret = do_trimming(block_group, total_trimmed, start, bytes, |
|
start, bytes, 0, &trim_entry); |
|
if (ret) { |
|
reset_trimming_bitmap(ctl, offset); |
|
block_group->discard_cursor = |
|
btrfs_block_group_end(block_group); |
|
break; |
|
} |
|
next: |
|
if (next_bitmap) { |
|
offset += BITS_PER_BITMAP * ctl->unit; |
|
start = offset; |
|
} else { |
|
start += bytes; |
|
} |
|
block_group->discard_cursor = start; |
|
|
|
if (fatal_signal_pending(current)) { |
|
if (start != offset) |
|
reset_trimming_bitmap(ctl, offset); |
|
ret = -ERESTARTSYS; |
|
break; |
|
} |
|
|
|
cond_resched(); |
|
} |
|
|
|
if (offset >= end) |
|
block_group->discard_cursor = end; |
|
|
|
out: |
|
return ret; |
|
} |
|
|
|
int btrfs_trim_block_group(struct btrfs_block_group *block_group, |
|
u64 *trimmed, u64 start, u64 end, u64 minlen) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
int ret; |
|
u64 rem = 0; |
|
|
|
ASSERT(!btrfs_is_zoned(block_group->fs_info)); |
|
|
|
*trimmed = 0; |
|
|
|
spin_lock(&block_group->lock); |
|
if (block_group->removed) { |
|
spin_unlock(&block_group->lock); |
|
return 0; |
|
} |
|
btrfs_freeze_block_group(block_group); |
|
spin_unlock(&block_group->lock); |
|
|
|
ret = trim_no_bitmap(block_group, trimmed, start, end, minlen, false); |
|
if (ret) |
|
goto out; |
|
|
|
ret = trim_bitmaps(block_group, trimmed, start, end, minlen, 0, false); |
|
div64_u64_rem(end, BITS_PER_BITMAP * ctl->unit, &rem); |
|
/* If we ended in the middle of a bitmap, reset the trimming flag */ |
|
if (rem) |
|
reset_trimming_bitmap(ctl, offset_to_bitmap(ctl, end)); |
|
out: |
|
btrfs_unfreeze_block_group(block_group); |
|
return ret; |
|
} |
|
|
|
int btrfs_trim_block_group_extents(struct btrfs_block_group *block_group, |
|
u64 *trimmed, u64 start, u64 end, u64 minlen, |
|
bool async) |
|
{ |
|
int ret; |
|
|
|
*trimmed = 0; |
|
|
|
spin_lock(&block_group->lock); |
|
if (block_group->removed) { |
|
spin_unlock(&block_group->lock); |
|
return 0; |
|
} |
|
btrfs_freeze_block_group(block_group); |
|
spin_unlock(&block_group->lock); |
|
|
|
ret = trim_no_bitmap(block_group, trimmed, start, end, minlen, async); |
|
btrfs_unfreeze_block_group(block_group); |
|
|
|
return ret; |
|
} |
|
|
|
int btrfs_trim_block_group_bitmaps(struct btrfs_block_group *block_group, |
|
u64 *trimmed, u64 start, u64 end, u64 minlen, |
|
u64 maxlen, bool async) |
|
{ |
|
int ret; |
|
|
|
*trimmed = 0; |
|
|
|
spin_lock(&block_group->lock); |
|
if (block_group->removed) { |
|
spin_unlock(&block_group->lock); |
|
return 0; |
|
} |
|
btrfs_freeze_block_group(block_group); |
|
spin_unlock(&block_group->lock); |
|
|
|
ret = trim_bitmaps(block_group, trimmed, start, end, minlen, maxlen, |
|
async); |
|
|
|
btrfs_unfreeze_block_group(block_group); |
|
|
|
return ret; |
|
} |
|
|
|
bool btrfs_free_space_cache_v1_active(struct btrfs_fs_info *fs_info) |
|
{ |
|
return btrfs_super_cache_generation(fs_info->super_copy); |
|
} |
|
|
|
static int cleanup_free_space_cache_v1(struct btrfs_fs_info *fs_info, |
|
struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_block_group *block_group; |
|
struct rb_node *node; |
|
int ret = 0; |
|
|
|
btrfs_info(fs_info, "cleaning free space cache v1"); |
|
|
|
node = rb_first(&fs_info->block_group_cache_tree); |
|
while (node) { |
|
block_group = rb_entry(node, struct btrfs_block_group, cache_node); |
|
ret = btrfs_remove_free_space_inode(trans, NULL, block_group); |
|
if (ret) |
|
goto out; |
|
node = rb_next(node); |
|
} |
|
out: |
|
return ret; |
|
} |
|
|
|
int btrfs_set_free_space_cache_v1_active(struct btrfs_fs_info *fs_info, bool active) |
|
{ |
|
struct btrfs_trans_handle *trans; |
|
int ret; |
|
|
|
/* |
|
* update_super_roots will appropriately set or unset |
|
* super_copy->cache_generation based on SPACE_CACHE and |
|
* BTRFS_FS_CLEANUP_SPACE_CACHE_V1. For this reason, we need a |
|
* transaction commit whether we are enabling space cache v1 and don't |
|
* have any other work to do, or are disabling it and removing free |
|
* space inodes. |
|
*/ |
|
trans = btrfs_start_transaction(fs_info->tree_root, 0); |
|
if (IS_ERR(trans)) |
|
return PTR_ERR(trans); |
|
|
|
if (!active) { |
|
set_bit(BTRFS_FS_CLEANUP_SPACE_CACHE_V1, &fs_info->flags); |
|
ret = cleanup_free_space_cache_v1(fs_info, trans); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
btrfs_end_transaction(trans); |
|
goto out; |
|
} |
|
} |
|
|
|
ret = btrfs_commit_transaction(trans); |
|
out: |
|
clear_bit(BTRFS_FS_CLEANUP_SPACE_CACHE_V1, &fs_info->flags); |
|
|
|
return ret; |
|
} |
|
|
|
#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS |
|
/* |
|
* Use this if you need to make a bitmap or extent entry specifically, it |
|
* doesn't do any of the merging that add_free_space does, this acts a lot like |
|
* how the free space cache loading stuff works, so you can get really weird |
|
* configurations. |
|
*/ |
|
int test_add_free_space_entry(struct btrfs_block_group *cache, |
|
u64 offset, u64 bytes, bool bitmap) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = cache->free_space_ctl; |
|
struct btrfs_free_space *info = NULL, *bitmap_info; |
|
void *map = NULL; |
|
enum btrfs_trim_state trim_state = BTRFS_TRIM_STATE_TRIMMED; |
|
u64 bytes_added; |
|
int ret; |
|
|
|
again: |
|
if (!info) { |
|
info = kmem_cache_zalloc(btrfs_free_space_cachep, GFP_NOFS); |
|
if (!info) |
|
return -ENOMEM; |
|
} |
|
|
|
if (!bitmap) { |
|
spin_lock(&ctl->tree_lock); |
|
info->offset = offset; |
|
info->bytes = bytes; |
|
info->max_extent_size = 0; |
|
ret = link_free_space(ctl, info); |
|
spin_unlock(&ctl->tree_lock); |
|
if (ret) |
|
kmem_cache_free(btrfs_free_space_cachep, info); |
|
return ret; |
|
} |
|
|
|
if (!map) { |
|
map = kmem_cache_zalloc(btrfs_free_space_bitmap_cachep, GFP_NOFS); |
|
if (!map) { |
|
kmem_cache_free(btrfs_free_space_cachep, info); |
|
return -ENOMEM; |
|
} |
|
} |
|
|
|
spin_lock(&ctl->tree_lock); |
|
bitmap_info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset), |
|
1, 0); |
|
if (!bitmap_info) { |
|
info->bitmap = map; |
|
map = NULL; |
|
add_new_bitmap(ctl, info, offset); |
|
bitmap_info = info; |
|
info = NULL; |
|
} |
|
|
|
bytes_added = add_bytes_to_bitmap(ctl, bitmap_info, offset, bytes, |
|
trim_state); |
|
|
|
bytes -= bytes_added; |
|
offset += bytes_added; |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
if (bytes) |
|
goto again; |
|
|
|
if (info) |
|
kmem_cache_free(btrfs_free_space_cachep, info); |
|
if (map) |
|
kmem_cache_free(btrfs_free_space_bitmap_cachep, map); |
|
return 0; |
|
} |
|
|
|
/* |
|
* Checks to see if the given range is in the free space cache. This is really |
|
* just used to check the absence of space, so if there is free space in the |
|
* range at all we will return 1. |
|
*/ |
|
int test_check_exists(struct btrfs_block_group *cache, |
|
u64 offset, u64 bytes) |
|
{ |
|
struct btrfs_free_space_ctl *ctl = cache->free_space_ctl; |
|
struct btrfs_free_space *info; |
|
int ret = 0; |
|
|
|
spin_lock(&ctl->tree_lock); |
|
info = tree_search_offset(ctl, offset, 0, 0); |
|
if (!info) { |
|
info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset), |
|
1, 0); |
|
if (!info) |
|
goto out; |
|
} |
|
|
|
have_info: |
|
if (info->bitmap) { |
|
u64 bit_off, bit_bytes; |
|
struct rb_node *n; |
|
struct btrfs_free_space *tmp; |
|
|
|
bit_off = offset; |
|
bit_bytes = ctl->unit; |
|
ret = search_bitmap(ctl, info, &bit_off, &bit_bytes, false); |
|
if (!ret) { |
|
if (bit_off == offset) { |
|
ret = 1; |
|
goto out; |
|
} else if (bit_off > offset && |
|
offset + bytes > bit_off) { |
|
ret = 1; |
|
goto out; |
|
} |
|
} |
|
|
|
n = rb_prev(&info->offset_index); |
|
while (n) { |
|
tmp = rb_entry(n, struct btrfs_free_space, |
|
offset_index); |
|
if (tmp->offset + tmp->bytes < offset) |
|
break; |
|
if (offset + bytes < tmp->offset) { |
|
n = rb_prev(&tmp->offset_index); |
|
continue; |
|
} |
|
info = tmp; |
|
goto have_info; |
|
} |
|
|
|
n = rb_next(&info->offset_index); |
|
while (n) { |
|
tmp = rb_entry(n, struct btrfs_free_space, |
|
offset_index); |
|
if (offset + bytes < tmp->offset) |
|
break; |
|
if (tmp->offset + tmp->bytes < offset) { |
|
n = rb_next(&tmp->offset_index); |
|
continue; |
|
} |
|
info = tmp; |
|
goto have_info; |
|
} |
|
|
|
ret = 0; |
|
goto out; |
|
} |
|
|
|
if (info->offset == offset) { |
|
ret = 1; |
|
goto out; |
|
} |
|
|
|
if (offset > info->offset && offset < info->offset + info->bytes) |
|
ret = 1; |
|
out: |
|
spin_unlock(&ctl->tree_lock); |
|
return ret; |
|
} |
|
#endif /* CONFIG_BTRFS_FS_RUN_SANITY_TESTS */
|
|
|