svn commit: r330950 - head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs

[Steven Hartland]

Missed the differential review: https://reviews.freebsd.org/D14695

On 14/03/2018 21:21, Steven Hartland wrote:
> Author: smh
> Date: Wed Mar 14 21:21:03 2018
> New Revision: 330950
> URL: https://svnweb.freebsd.org/changeset/base/330950
>
> Log:
>    Prevent ZFS TRIM breaking VTOC8 partitions
>    
>    Update the ZFS TRIM code to ensure it respects VTOC8 partition headers as
>    documented by the ZFS On-Disk Specification section 1.3
>    
>    Before this a zpool create on a VTOC8 partitioned device would overwrite the
>    partition metadata.
>    
>    Reported by:	marius
>    Reviewed by:	marius agv
>    MFC after:	1 week
>    Sponsored by:	Multiplay
>
> Modified:
>    head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_label.c
>
> Modified: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_label.c
> ==============================================================================
> --- head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_label.c	Wed Mar 14 21:11:41 2018	(r330949)
> +++ head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_label.c	Wed Mar 14 21:21:03 2018	(r330950)
> @@ -802,7 +802,9 @@ vdev_label_init(vdev_t *vd, uint64_t crtxg, vdev_label
>   	}
>   
>   	/*
> -	 * TRIM the whole thing so that we start with a clean slate.
> +	 * TRIM the whole thing, excluding the blank space and boot header
> +	 * as specified by ZFS On-Disk Specification (section 1.3), so that
> +	 * we start with a clean slate.
>   	 * It's just an optimization, so we don't care if it fails.
>   	 * Don't TRIM if removing so that we don't interfere with zpool
>   	 * disaster recovery.
> @@ -810,7 +812,8 @@ vdev_label_init(vdev_t *vd, uint64_t crtxg, vdev_label
>   	if (zfs_trim_enabled && vdev_trim_on_init && !vd->vdev_notrim &&
>   	    (reason == VDEV_LABEL_CREATE || reason == VDEV_LABEL_SPARE ||
>   	    reason == VDEV_LABEL_L2CACHE))
> -		zio_wait(zio_trim(NULL, spa, vd, 0, vd->vdev_psize));
> +		zio_wait(zio_trim(NULL, spa, vd, VDEV_SKIP_SIZE,
> +		    vd->vdev_psize - VDEV_SKIP_SIZE));
>   
>   	/*
>   	 * Initialize its label.
>