On 26.03.19 г. 21:02 ч., Goldwyn Rodrigues wrote:
> From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
>
> We require this to set the IOMAP_F_COW flag in
> iomap structure, in the later patches.
>
> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
> ---
> fs/btrfs/ctree.h | 2 +-
> fs/btrfs/inode.c | 9 +++++++--
> 2 files changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
> index b7bbe5130a3b..2c49d3c46170 100644
> --- a/fs/btrfs/ctree.h
> +++ b/fs/btrfs/ctree.h
> @@ -3278,7 +3278,7 @@ struct inode *btrfs_iget_path(struct super_block *s, struct btrfs_key *location,
> struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
> struct btrfs_root *root, int *was_new);
> int btrfs_get_extent_map_write(struct extent_map **map, struct buffer_head *bh,
> - struct inode *inode, u64 start, u64 len);
> + struct inode *inode, u64 start, u64 len, int *nocow);
If this is going to be used as a boolean flag, then define is as boolean *
> struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
> struct page *page, size_t pg_offset,
> u64 start, u64 end, int create);
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index 80184d0c3b52..c8702e0b5e66 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -7499,12 +7499,15 @@ static int btrfs_get_blocks_direct_read(struct extent_map *em,
> int btrfs_get_extent_map_write(struct extent_map **map,
> struct buffer_head *bh,
> struct inode *inode,
> - u64 start, u64 len)
> + u64 start, u64 len, int *nocow)
> {
> struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
> struct extent_map *em = *map;
> int ret = 0;
>
> + if (nocow)
> + *nocow = 0;
> +
> /*
> * We don't allocate a new extent in the following cases
> *
> @@ -7553,6 +7556,8 @@ int btrfs_get_extent_map_write(struct extent_map **map,
> */
> btrfs_free_reserved_data_space_noquota(inode, start,
> len);
> + if (nocow)
> + *nocow = 1;
> /* skip COW */
> goto out;
> }
> @@ -7579,7 +7584,7 @@ static int btrfs_get_blocks_direct_write(struct extent_map **map,
> struct extent_map *em;
>
> ret = btrfs_get_extent_map_write(map, bh_result, inode,
> - start, len);
> + start, len, NULL);
> if (ret < 0)
> return ret;
> em = *map;
>
