Re: [PATCH 2/6] f2fs: support goingdown for fs shutdown

[Eric Sandeen <sandeen@sandeen.net>]

On 1/8/15 12:10 PM, Jaegeuk Kim wrote:
> This patch add an ioctl to shutdown f2fs, which stops all the further block
> writes after this point.

would it make sense to just re-use the xfs ioctl nr, if the semantics are
the same?

That way any test using it will "just work" on f2fs...

-Eric

> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
>  fs/f2fs/f2fs.h |  1 +
>  fs/f2fs/file.c | 14 ++++++++++++++
>  2 files changed, 15 insertions(+)
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index ba30218..febad35 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -209,6 +209,7 @@ static inline bool __has_cursum_space(struct f2fs_summary_block *sum, int size,
>  #define F2FS_IOC_START_VOLATILE_WRITE	_IO(F2FS_IOCTL_MAGIC, 3)
>  #define F2FS_IOC_RELEASE_VOLATILE_WRITE	_IO(F2FS_IOCTL_MAGIC, 4)
>  #define F2FS_IOC_ABORT_VOLATILE_WRITE	_IO(F2FS_IOCTL_MAGIC, 5)
> +#define F2FS_IOC_GOINGDOWN		_IO(F2FS_IOCTL_MAGIC, 6)
>  
>  #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
>  /*
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index 5df3367..de2f669 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -1020,6 +1020,18 @@ static int f2fs_ioc_abort_volatile_write(struct file *filp)
>  	return ret;
>  }
>  
> +static int f2fs_ioc_goingdown(struct file *filp)
> +{
> +	struct inode *inode = file_inode(filp);
> +	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> +
> +	if (!capable(CAP_SYS_ADMIN))
> +		return -EPERM;
> +
> +	f2fs_stop_checkpoint(sbi);
> +	return 0;
> +}
> +
>  static int f2fs_ioc_fitrim(struct file *filp, unsigned long arg)
>  {
>  	struct inode *inode = file_inode(filp);
> @@ -1067,6 +1079,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
>  		return f2fs_ioc_release_volatile_write(filp);
>  	case F2FS_IOC_ABORT_VOLATILE_WRITE:
>  		return f2fs_ioc_abort_volatile_write(filp);
> +	case F2FS_IOC_GOINGDOWN:
> +		return f2fs_ioc_goingdown(filp);
>  	case FITRIM:
>  		return f2fs_ioc_fitrim(filp, arg);
>  	default:
>