linux/fs/btrfs/reflink.c

// SPDX-License-Identifier: GPL-2.0

#include <linux/blkdev.h>
#include <linux/iversion.h>
#include "ctree.h"
#include "fs.h"
#include "messages.h"
#include "compression.h"
#include "delalloc-space.h"
#include "disk-io.h"
#include "reflink.h"
#include "transaction.h"
#include "subpage.h"
#include "accessors.h"
#include "file-item.h"
#include "file.h"
#include "super.h"

#define BTRFS_MAX_DEDUPE_LEN …

static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
				     struct inode *inode,
				     u64 endoff,
				     const u64 destoff,
				     const u64 olen,
				     int no_time_update)
{ … }

static int copy_inline_to_page(struct btrfs_inode *inode,
			       const u64 file_offset,
			       char *inline_data,
			       const u64 size,
			       const u64 datal,
			       const u8 comp_type)
{ … }

/*
 * Deal with cloning of inline extents. We try to copy the inline extent from
 * the source inode to destination inode when possible. When not possible we
 * copy the inline extent's data into the respective page of the inode.
 */
static int clone_copy_inline_extent(struct inode *dst,
				    struct btrfs_path *path,
				    struct btrfs_key *new_key,
				    const u64 drop_start,
				    const u64 datal,
				    const u64 size,
				    const u8 comp_type,
				    char *inline_data,
				    struct btrfs_trans_handle **trans_out)
{ … }

/*
 * Clone a range from inode file to another.
 *
 * @src:             Inode to clone from
 * @inode:           Inode to clone to
 * @off:             Offset within source to start clone from
 * @olen:            Original length, passed by user, of range to clone
 * @olen_aligned:    Block-aligned value of olen
 * @destoff:         Offset within @inode to start clone
 * @no_time_update:  Whether to update mtime/ctime on the target inode
 */
static int btrfs_clone(struct inode *src, struct inode *inode,
		       const u64 off, const u64 olen, const u64 olen_aligned,
		       const u64 destoff, int no_time_update)
{ … }

static void btrfs_double_mmap_lock(struct inode *inode1, struct inode *inode2)
{ … }

static void btrfs_double_mmap_unlock(struct inode *inode1, struct inode *inode2)
{ … }

static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 len,
				   struct inode *dst, u64 dst_loff)
{ … }

static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
			     struct inode *dst, u64 dst_loff)
{ … }

static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
					u64 off, u64 olen, u64 destoff)
{ … }

static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in,
				       struct file *file_out, loff_t pos_out,
				       loff_t *len, unsigned int remap_flags)
{ … }

static bool file_sync_write(const struct file *file)
{ … }

loff_t btrfs_remap_file_range(struct file *src_file, loff_t off,
		struct file *dst_file, loff_t destoff, loff_t len,
		unsigned int remap_flags)
{ … }