Re: [gentoo-user] Can't create valid btrfs on NVMe

[Adam Carter]

On Thu, Aug 18, 2016 at 8:26 AM, Neil Bothwick <neil@××××××××××.uk> wrote:

> I'm putting together a new desktop using a Samsung SM951 NVMe drive. I
> booted sysrescd, partitioned the drive and ran
>
> mkfs.btrfs /dev/nvme0n1p3
> mount /dev/nvme0n1p3 /mnt/custom
>
> df -T, mount and findmnt all show this is mounted as a btrfs filesystem,
> e.g.
>
> /dev/nvme0n1p3 on /mnt/custom type btrfs (rw,relatime,ssd,space_cache)
>
> I can create files in here but cannot do anything btrfs-y
>
> % btrfs filesystem show /mnt/custom
> ERROR: not a valid btrfs filesystem: /mnt/custom
>
> % btrfs subvolume create /mnt/custom/test
> Create subvolume '/mnt/custom/test'
> ERROR: cannot create subvolume: Inappropriate ioctl for device
>
> Google has been no help at all.
>
>
I'm assuming tools are expecting SATA (or SCSI) and need an update or
alternative for nvm;

# hdparm -i /dev/nvme0n1

/dev/nvme0n1:
 HDIO_DRIVE_CMD(identify) failed: Inappropriate ioctl for device
 HDIO_GET_IDENTITY failed: Inappropriate ioctl for device

Maybe SCSI emulation could work around it?
CONFIG_BLK_DEV_NVME_SCSI