Hi, Qu,
On 2015/09/08 18:08, Qu Wenruo wrote:
> Introduce functions btrfs_qgroup_release/free_data() to release/free
> reserved data range.
>
> Release means, just remove the data range from data rsv map, but doesn't
> free the reserved space.
> This is for normal buffered write case, when data is written into disc
> and its metadata is added into tree, its reserved space should still be
> kept until commit_trans().
> So in that case, we only release dirty range, but keep the reserved
> space recorded some other place until commit_tran().
>
> Free means not only remove data range, but also free reserved space.
> This is used for case for cleanup.
>
> Signed-off-by: Qu Wenruo <quwenruo@xxxxxxxxxxxxxx>
> ---
> fs/btrfs/qgroup.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
> fs/btrfs/qgroup.h | 2 ++
> 2 files changed, 50 insertions(+)
>
> diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
> index e24c10d..ba7888f 100644
> --- a/fs/btrfs/qgroup.c
> +++ b/fs/btrfs/qgroup.c
> @@ -2979,6 +2979,54 @@ next:
> return 0;
> }
>
> +static int __btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len,
> + int free_reserved)
> +{
> + struct data_rsv_range *tmp;
> + struct btrfs_qgroup_data_rsv_map *map;
> + u64 reserved = 0;
> + int ret;
> +
> + spin_lock(&BTRFS_I(inode)->qgroup_init_lock);
> + map = BTRFS_I(inode)->qgroup_rsv_map;
> + spin_unlock(&BTRFS_I(inode)->qgroup_init_lock);
> + if (!map)
> + return 0;
> +
> + tmp = kmalloc(sizeof(*tmp), GFP_NOFS);
> + if (!tmp)
> + return -ENOMEM;
> + spin_lock(&map->lock);
> + ret = release_data_range(map, tmp, start, len, &reserved);
> + /* release_data_range() won't fail only check if memory is used */
> + if (ret == 0)
> + kfree(tmp);
> + if (free_reserved)
> + btrfs_qgroup_free(BTRFS_I(inode)->root, reserved);
> + spin_unlock(&map->lock);
> + return 0;
> +}
> +
> +/*
> + * Caller should be truncate/invalidate_page.
> + * As it will release the reserved data.
> + */
> +int btrfs_qgroup_free_data(struct inode *inode, u64 start, u64 len)
> +{
> + return __btrfs_qgroup_release_data(inode, start, len, 1);
> +}
> +
> +/*
> + * Caller should be finish_ordered_io
> + * As qgroup accouting happens at commit time, for data written to disk
accounting
Thanks,
Tsutomu
> + * its reserved space should not be freed until commit.
> + * Or we may beyond the limit.
> + */
> +int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len)
> +{
> + return __btrfs_qgroup_release_data(inode, start, len, 0);
> +}
> +
> /*
> * Init data_rsv_map for a given inode.
> *
> diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h
> index 366b853..8e69dc1 100644
> --- a/fs/btrfs/qgroup.h
> +++ b/fs/btrfs/qgroup.h
> @@ -88,4 +88,6 @@ int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
> int btrfs_qgroup_init_data_rsv_map(struct inode *inode);
> void btrfs_qgroup_free_data_rsv_map(struct inode *inode);
> int btrfs_qgroup_reserve_data(struct inode *inode, u64 start, u64 len);
> +int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len);
> +int btrfs_qgroup_free_data(struct inode *inode, u64 start, u64 len);
> #endif /* __BTRFS_QGROUP__ */
>
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
