path: root/fs/btrfs/delalloc-space.c

// SPDX-License-Identifier: GPL-2.0

#include "ctree.h"
#include "delalloc-space.h"
#include "block-rsv.h"
#include "btrfs_inode.h"
#include "space-info.h"
#include "transaction.h"
#include "qgroup.h"

int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
{
	struct btrfs_root *root = inode->root;
	struct btrfs_fs_info *fs_info = root->fs_info;
	struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
	u64 used;
	int ret = 0;
	int need_commit = 2;
	int have_pinned_space;

	/* Make sure bytes are sectorsize aligned */
	bytes = ALIGN(bytes, fs_info->sectorsize);

	if (btrfs_is_free_space_inode(inode)) {
		need_commit = 0;
		ASSERT(current->journal_info);
	}

again:
	/* Make sure we have enough space to handle the data first */
	spin_lock(&data_sinfo->lock);
	used = btrfs_space_info_used(data_sinfo, true);

	if (used + bytes > data_sinfo->total_bytes) {
		struct btrfs_trans_handle *trans;

		/*
		 * If we don't have enough free bytes in this space then we need
		 * to alloc a new chunk.
		 */
		if (!data_sinfo->full) {
			u64 alloc_target;

			data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
			spin_unlock(&data_sinfo->lock);

			alloc_target = btrfs_data_alloc_profile(fs_info);
			/*
			 * It is ugly that we don't call nolock join
			 * transaction for the free space inode case here.
			 * But it is safe because we only do the data space
			 * reservation for the free space cache in the
			 * transaction context, the common join transaction
			 * just increase the counter of the current transaction
			 * handler, doesn't try to acquire the trans_lock of
			 * the fs.
			 */
			trans = btrfs_join_transaction(root);
			if (IS_ERR(trans))
				return PTR_ERR(trans);

			ret = btrfs_chunk_alloc(trans, alloc_target,
						CHUNK_ALLOC_NO_FORCE);
			btrfs_end_transaction(trans);
			if (ret < 0) {
				if (ret != -ENOSPC)
					return ret;
				else {
					have_pinned_space = 1;
					goto commit_trans;
				}
			}

			goto again;
		}

		/*
		 * If we don't have enough pinned space to deal with this
		 * allocation, and no removed chunk in current transaction,
		 * don't bother committing the transaction.
		 */
		have_pinned_space = __percpu_counter_compare(
			&data_sinfo->total_bytes_pinned,
			used + bytes - data_sinfo->total_bytes,
			BTRFS_TOTAL_BYTES_PINNED_BATCH);
		spin_unlock(&data_sinfo->lock);

		/* Commit the current transaction and try again */
commit_trans:
		if (need_commit) {
			need_commit--;

			if (need_commit > 0) {
				btrfs_start_delalloc_roots(fs_info, -1);
				btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,
							 (u64)-1);
			}

			trans = btrfs_join_transaction(root);
			if (IS_ERR(trans))
				return PTR_ERR(trans);
			if (have_pinned_space >= 0 ||
			    test_bit(BTRFS_TRANS_HAVE_FREE_BGS,
				     &trans->transaction->flags) ||
			    need_commit > 0) {
				ret = btrfs_commit_transaction(trans);
				if (ret)
					return ret;
				/*
				 * The cleaner kthread might still be doing iput
				 * operations. Wait for it to finish so that
				 * more space is released.  We don't need to
				 * explicitly run the delayed iputs here because
				 * the commit_transaction would have woken up
				 * the cleaner.
				 */
				ret = btrfs_wait_on_delayed_iputs(fs_info);
				if (ret)
					return ret;
				goto again;
			} else {
				btrfs_end_transaction(trans);
			}
		}

		trace_btrfs_space_reservation(fs_info,
					      "space_info:enospc",
					      data_sinfo->flags, bytes, 1);
		return -ENOSPC;
	}
	btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, bytes);
	trace_btrfs_space_reservation(fs_info, "space_info",
				      data_sinfo->flags, bytes, 1);
	spin_unlock(&data_sinfo->lock);

	return 0;
}

int btrfs_check_data_free_space(struct inode *inode,
			struct extent_changeset **reserved, u64 start, u64 len)
{
	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
	int ret;

	/* align the range */
	len = round_up(start + len, fs_info->sectorsize) -
	      round_down(start, fs_info->sectorsize);
	start = round_down(start, fs_info->sectorsize);

	ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), len);
	if (ret < 0)
		return ret;

	/* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
	ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
	if (ret < 0)
		btrfs_free_reserved_data_space_noquota(inode, start, len);
	else
		ret = 0;
	return ret;
}

/*
 * Called if we need to clear a data reservation for this inode
 * Normally in a error case.
 *
 * This one will *NOT* use accurate qgroup reserved space API, just for case
 * which we can't sleep and is sure it won't affect qgroup reserved space.
 * Like clear_bit_hook().
 */
void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
					    u64 len)
{
	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
	struct btrfs_space_info *data_sinfo;

	/* Make sure the range is aligned to sectorsize */
	len = round_up(start + len, fs_info->sectorsize) -
	      round_down(start, fs_info->sectorsize);
	start = round_down(start, fs_info->sectorsize);

	data_sinfo = fs_info->data_sinfo;
	spin_lock(&data_sinfo->lock);
	btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, -len);
	trace_btrfs_space_reservation(fs_info, "space_info",
				      data_sinfo->flags, len, 0);
	spin_unlock(&data_sinfo->lock);
}

/*
 * Called if we need to clear a data reservation for this inode
 * Normally in a error case.
 *
 * This one will handle the per-inode data rsv map for accurate reserved
 * space framework.
 */
void btrfs_free_reserved_data_space(struct inode *inode,
			struct extent_changeset *reserved, u64 start, u64 len)
{
	struct btrfs_root *root = BTRFS_I(inode)->root;

	/* Make sure the range is aligned to sectorsize */
	len = round_up(start + len, root->fs_info->sectorsize) -
	      round_down(start, root->fs_info->sectorsize);
	start = round_down(start, root->fs_info->sectorsize);

	btrfs_free_reserved_data_space_noquota(inode, start, len);
	btrfs_qgroup_free_data(inode, reserved, start, len);
}

/**
 * btrfs_inode_rsv_release - release any excessive reservation.
 * @inode - the inode we need to release from.
 * @qgroup_free - free or convert qgroup meta.
 *   Unlike normal operation, qgroup meta reservation needs to know if we are
 *   freeing qgroup reservation or just converting it into per-trans.  Normally
 *   @qgroup_free is true for error handling, and false for normal release.
 *
 * This is the same as btrfs_block_rsv_release, except that it handles the
 * tracepoint for the reservation.
 */
static void btrfs_inode_rsv_release(struct btrfs_inode *inode, bool qgroup_free)
{
	struct btrfs_fs_info *fs_info = inode->root->fs_info;
	struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
	u64 released = 0;
	u64 qgroup_to_release = 0;

	/*
	 * Since we statically set the block_rsv->size we just want to say we
	 * are releasing 0 bytes, and then we'll just get the reservation over
	 * the size free'd.
	 */
	released = __btrfs_block_rsv_release(fs_info, block_rsv, 0,
					     &qgroup_to_release);
	if (released > 0)
		trace_btrfs_space_reservation(fs_info, "delalloc",
					      btrfs_ino(inode), released, 0);
	if (qgroup_free)
		btrfs_qgroup_free_meta_prealloc(inode->root, qgroup_to_release);
	else
		btrfs_qgroup_convert_reserved_meta(inode->root,
						   qgroup_to_release);
}

static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info *fs_info,
						 struct btrfs_inode *inode)
{
	struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
	u64 reserve_size = 0;
	u64 qgroup_rsv_size = 0;
	u64 csum_leaves;
	unsigned outstanding_extents;

	lockdep_assert_held(&inode->lock);
	outstanding_extents = inode->outstanding_extents;
	if (outstanding_extents)
		reserve_size = btrfs_calc_trans_metadata_size(fs_info,
						outstanding_extents +