From mboxrd@z Thu Jan  1 00:00:00 1970
From: ming.lei@redhat.com (Ming Lei)
Date: Wed, 13 Mar 2019 09:46:47 +0800
Subject: [PATCH] nvme: disable Write Zeroes for qemu controllers
In-Reply-To: <20190312151256.22986-1-hch@lst.de>
References: <20190312151256.22986-1-hch@lst.de>
Message-ID: <20190313014646.GB10726@ming.t460p>

On Tue, Mar 12, 2019@04:12:56PM +0100, Christoph Hellwig wrote:
> Qemu started out with a broken implementation of Write Zeroes written
> by yours truly.  Disable Write Zeroes on qemu for now, eventually
> we need to go back and make all the qemu quirks version specific,
> but that is left for another time.
> 
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> ---
>  drivers/nvme/host/core.c | 3 ++-
>  drivers/nvme/host/nvme.h | 5 +++++
>  drivers/nvme/host/pci.c  | 3 ++-
>  3 files changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index 17ebc4055ac8..15ab73e5c9fc 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -1531,7 +1531,8 @@ static void nvme_config_write_zeroes(struct gendisk *disk, struct nvme_ns *ns)
>  	u32 max_sectors;
>  	unsigned short bs = 1 << ns->lba_shift;
>  
> -	if (!(ns->ctrl->oncs & NVME_CTRL_ONCS_WRITE_ZEROES))
> +	if (!(ns->ctrl->oncs & NVME_CTRL_ONCS_WRITE_ZEROES) ||
> +	    (ns->ctrl->quirks & NVME_QUIRK_DISABLE_WRITE_ZEROES))
>  		return;
>  	/*
>  	 * Even though NVMe spec explicitly states that MDTS is not
> diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
> index b91f1838bbd5..527d64545023 100644
> --- a/drivers/nvme/host/nvme.h
> +++ b/drivers/nvme/host/nvme.h
> @@ -87,6 +87,11 @@ enum nvme_quirks {
>  	 * Ignore device provided subnqn.
>  	 */
>  	NVME_QUIRK_IGNORE_DEV_SUBNQN		= (1 << 8),
> +
> +	/*
> +	 * Broken Write Zeroes.
> +	 */
> +	NVME_QUIRK_DISABLE_WRITE_ZEROES		= (1 << 9),
>  };
>  
>  /*
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index f54718b63637..3a2377888a46 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -2975,7 +2975,8 @@ static const struct pci_device_id nvme_id_table[] = {
>  	{ PCI_VDEVICE(INTEL, 0xf1a6),	/* Intel 760p/Pro 7600p */
>  		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN, },
>  	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
> -		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
> +		.driver_data = NVME_QUIRK_IDENTIFY_CNS |
> +				NVME_QUIRK_DISABLE_WRITE_ZEROES, },
>  	{ PCI_DEVICE(0x1bb1, 0x0100),   /* Seagate Nytro Flash Storage */
>  		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
>  	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
> -- 
> 2.20.1
> 

Tested-by: Ming Lei <ming.lei at redhat.com>

-- 
Ming