linux/fs/btrfs/tree-log.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 2008 Oracle.  All rights reserved.
 */

#ifndef BTRFS_TREE_LOG_H
#define BTRFS_TREE_LOG_H

#include <linux/list.h>
#include <linux/fs.h>
#include "messages.h"
#include "ctree.h"
#include "transaction.h"

struct inode;
struct dentry;
struct btrfs_ordered_extent;
struct btrfs_root;
struct btrfs_trans_handle;

/* return value for btrfs_log_dentry_safe that means we don't need to log it at all */
#define BTRFS_NO_LOG_SYNC 256

/*
 * We can't use the tree log for whatever reason, force a transaction commit.
 * We use a negative value because there are functions through the logging code
 * that need to return an error (< 0 value), false (0) or true (1). Any negative
 * value will do, as it will cause the log to be marked for a full sync.
 */
#define BTRFS_LOG_FORCE_COMMIT				(-(MAX_ERRNO + 1))

struct btrfs_log_ctx {
	int log_ret;
	int log_transid;
	bool log_new_dentries;
	bool logging_new_name;
	bool logging_new_delayed_dentries;
	/* Indicate if the inode being logged was logged before. */
	bool logged_before;
	struct inode *inode;
	struct list_head list;
	/* Only used for fast fsyncs. */
	struct list_head ordered_extents;
	struct list_head conflict_inodes;
	int num_conflict_inodes;
	bool logging_conflict_inodes;
	/*
	 * Used for fsyncs that need to copy items from the subvolume tree to
	 * the log tree (full sync flag set or copy everything flag set) to
	 * avoid allocating a temporary extent buffer while holding a lock on
	 * an extent buffer of the subvolume tree and under the log transaction.
	 * Also helps to avoid allocating and freeing a temporary extent buffer
	 * in case we need to process multiple leaves from the subvolume tree.
	 */
	struct extent_buffer *scratch_eb;
};

static inline void btrfs_init_log_ctx(struct btrfs_log_ctx *ctx,
				      struct inode *inode)
{
	ctx->log_ret = 0;
	ctx->log_transid = 0;
	ctx->log_new_dentries = false;
	ctx->logging_new_name = false;
	ctx->logging_new_delayed_dentries = false;
	ctx->logged_before = false;
	ctx->inode = inode;
	INIT_LIST_HEAD(&ctx->list);
	INIT_LIST_HEAD(&ctx->ordered_extents);
	INIT_LIST_HEAD(&ctx->conflict_inodes);
	ctx->num_conflict_inodes = 0;
	ctx->logging_conflict_inodes = false;
	ctx->scratch_eb = NULL;
}

static inline void btrfs_init_log_ctx_scratch_eb(struct btrfs_log_ctx *ctx)
{
	struct btrfs_inode *inode = BTRFS_I(ctx->inode);

	if (!test_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags) &&
	    !test_bit(BTRFS_INODE_COPY_EVERYTHING, &inode->runtime_flags))
		return;

	/*
	 * Don't care about allocation failure. This is just for optimization,
	 * if we fail to allocate here, we will try again later if needed.
	 */
	ctx->scratch_eb = alloc_dummy_extent_buffer(inode->root->fs_info, 0);
}

static inline void btrfs_release_log_ctx_extents(struct btrfs_log_ctx *ctx)
{
	struct btrfs_ordered_extent *ordered;
	struct btrfs_ordered_extent *tmp;

	ASSERT(inode_is_locked(ctx->inode));

	list_for_each_entry_safe(ordered, tmp, &ctx->ordered_extents, log_list) {
		list_del_init(&ordered->log_list);
		btrfs_put_ordered_extent(ordered);
	}
}

static inline void btrfs_set_log_full_commit(struct btrfs_trans_handle *trans)
{
	WRITE_ONCE(trans->fs_info->last_trans_log_full_commit, trans->transid);
}

static inline int btrfs_need_log_full_commit(struct btrfs_trans_handle *trans)
{
	return READ_ONCE(trans->fs_info->last_trans_log_full_commit) ==
		trans->transid;
}

int btrfs_sync_log(struct btrfs_trans_handle *trans,
		   struct btrfs_root *root, struct btrfs_log_ctx *ctx);
int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root);
int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans,
			     struct btrfs_fs_info *fs_info);
int btrfs_recover_log_trees(struct btrfs_root *tree_root);
int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
			  struct dentry *dentry,
			  struct btrfs_log_ctx *ctx);
void btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
				  struct btrfs_root *root,
				  const struct fscrypt_str *name,
				  struct btrfs_inode *dir, u64 index);
void btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
				struct btrfs_root *root,
				const struct fscrypt_str *name,
				struct btrfs_inode *inode, u64 dirid);
void btrfs_end_log_trans(struct btrfs_root *root);
void btrfs_pin_log_trans(struct btrfs_root *root);
void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans,
			     struct btrfs_inode *dir, struct btrfs_inode *inode,
			     bool for_rename);
void btrfs_record_snapshot_destroy(struct btrfs_trans_handle *trans,
				   struct btrfs_inode *dir);
void btrfs_log_new_name(struct btrfs_trans_handle *trans,
			struct dentry *old_dentry, struct btrfs_inode *old_dir,
			u64 old_dir_index, struct dentry *parent);

#endif