Re: [PATCH v4 6/8] xfs: add XFS_IOC_FREE_EOFBLOCKS ioctl

Dave Chinner
2012-09-28T07:24:33Z

On Thu, Sep 27, 2012 at 01:45:50PM -0400, Brian Foster wrote:
> The XFS_IOC_FREE_EOFBLOCKS ioctl allows users to invoke an EOFBLOCKS
> scan. The xfs_eofblocks structure is defined to support the command
> parameters (scan mode).
>
> Signed-off-by: Brian Foster <bfoster@redhat.com>
> ---
> fs/xfs/xfs_fs.h | 14 ++++++++++++++
> fs/xfs/xfs_ioctl.c | 12 ++++++++++++
> 2 files changed, 26 insertions(+), 0 deletions(-)
>
> diff --git a/fs/xfs/xfs_fs.h b/fs/xfs/xfs_fs.h
> index c13fed8..32bb2e8 100644
> --- a/fs/xfs/xfs_fs.h
> +++ b/fs/xfs/xfs_fs.h
> @@ -339,6 +339,19 @@ typedef struct xfs_error_injection {
>
>
> /*
> + * Speculative preallocation trimming.
> + */
> +struct xfs_eofblocks {
> + __u32 eof_flags;
> + __s32 version;
__u32

> + unsigned char pad[12];
> +};
> +
> +/* eof_flags values */
> +#define XFS_EOF_FLAGS_FORCE 0x01 /* force/wait mode scan */

Might be better defined as XFS_EOF_FLAGS_SYNC as that is more
consistent with what users see as a blocking operation that waits
for completion to occur.

Also, you need to define the structure version here as well (i.e. v1).

> +
> +
> +/*
> * The user-level Handle Request interface structure.
> */
> typedef struct xfs_fsop_handlereq {
> @@ -456,6 +469,7 @@ typedef struct xfs_handle {
> /* XFS_IOC_GETBIOSIZE ---- deprecated 47 */
> #define XFS_IOC_GETBMAPX _IOWR('X', 56, struct getbmap)
> #define XFS_IOC_ZERO_RANGE _IOW ('X', 57, struct xfs_flock64)
> +#define XFS_IOC_FREE_EOFBLOCKS _IOR ('X', 58, struct xfs_eofblocks)
>
> /*
> * ioctl commands that replace IRIX syssgi()'s
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index 0e0232c..216ca7a 100644
> --- a/fs/xfs/xfs_ioctl.c
> +++ b/fs/xfs/xfs_ioctl.c
> @@ -1602,6 +1602,18 @@ xfs_file_ioctl(
> error = xfs_errortag_clearall(mp, 1);
> return -error;
>
> + case XFS_IOC_FREE_EOFBLOCKS: {
> + struct xfs_eofblocks eofb;
> + int flags;
> +
> + if (copy_from_user(&eofb, arg, sizeof(eofb)))
> + return -XFS_ERROR(EFAULT);

And check the version here, too.

Cheers,

Dave.
--
Dave Chinner
david@fromorbit.com