[v2,40/44] scsi: usb: Stop using the SCSI pointer

Set scsi_host_template.cmd_size instead of using the SCSI pointer for
storing driver-private data. Change the type of the argument of
uas_add_work() from struct uas_cmd_info * into struct scsi_cmnd * because
it is easier to convert a SCSI command pointer into a uas_cmd_info pointer
than the other way around.

This patch prepares for removal of the SCSI pointer from struct scsi_cmnd.

Cc: linux-usb@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 drivers/usb/storage/uas.c | 43 ++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 23 deletions(-)

On 2/8/22 18:25, Bart Van Assche wrote:
> Set scsi_host_template.cmd_size instead of using the SCSI pointer for
> storing driver-private data. Change the type of the argument of
> uas_add_work() from struct uas_cmd_info * into struct scsi_cmnd * because
> it is easier to convert a SCSI command pointer into a uas_cmd_info pointer
> than the other way around.
> 
> This patch prepares for removal of the SCSI pointer from struct scsi_cmnd.
> 
> Cc: linux-usb@vger.kernel.org
> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Acked-by: Oliver Neukum <oneukum@suse.com>
> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
> ---
>   drivers/usb/storage/uas.c | 43 ++++++++++++++++++---------------------
>   1 file changed, 20 insertions(+), 23 deletions(-)
> 
Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes

> On Feb 8, 2022, at 9:25 AM, Bart Van Assche <bvanassche@acm.org> wrote:
> 
> Set scsi_host_template.cmd_size instead of using the SCSI pointer for
> storing driver-private data. Change the type of the argument of
> uas_add_work() from struct uas_cmd_info * into struct scsi_cmnd * because
> it is easier to convert a SCSI command pointer into a uas_cmd_info pointer
> than the other way around.
> 
> This patch prepares for removal of the SCSI pointer from struct scsi_cmnd.
> 
> Cc: linux-usb@vger.kernel.org
> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Acked-by: Oliver Neukum <oneukum@suse.com>
> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
> ---
> drivers/usb/storage/uas.c | 43 ++++++++++++++++++---------------------
> 1 file changed, 20 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
> index 7f2944729ecd..84dc270f6f73 100644
> --- a/drivers/usb/storage/uas.c
> +++ b/drivers/usb/storage/uas.c
> @@ -113,7 +113,7 @@ static void uas_do_work(struct work_struct *work)
> 			continue;
> 
> 		cmnd = devinfo->cmnd[i];
> -		cmdinfo = (void *)&cmnd->SCp;
> +		cmdinfo = scsi_cmd_priv(cmnd);
> 
> 		if (!(cmdinfo->state & IS_IN_WORK_LIST))
> 			continue;
> @@ -139,10 +139,9 @@ static void uas_scan_work(struct work_struct *work)
> 	dev_dbg(&devinfo->intf->dev, "scan complete\n");
> }
> 
> -static void uas_add_work(struct uas_cmd_info *cmdinfo)
> +static void uas_add_work(struct scsi_cmnd *cmnd)
> {
> -	struct scsi_pointer *scp = (void *)cmdinfo;
> -	struct scsi_cmnd *cmnd = container_of(scp, struct scsi_cmnd, SCp);
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
> 
> 	lockdep_assert_held(&devinfo->lock);
> @@ -163,7 +162,7 @@ static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
> 			continue;
> 
> 		cmnd = devinfo->cmnd[i];
> -		cmdinfo = (void *)&cmnd->SCp;
> +		cmdinfo = scsi_cmd_priv(cmnd);
> 		uas_log_cmd_state(cmnd, __func__, 0);
> 		/* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
> 		cmdinfo->state &= ~COMMAND_INFLIGHT;
> @@ -200,15 +199,14 @@ static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
> static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
> 			      int status)
> {
> -	struct uas_cmd_info *ci = (void *)&cmnd->SCp;
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *ci = scsi_cmd_priv(cmnd);
> 
> 	if (status == -ENODEV) /* too late */
> 		return;
> 
> 	scmd_printk(KERN_INFO, cmnd,
> 		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
> -		    prefix, status, cmdinfo->uas_tag,
> +		    prefix, status, ci->uas_tag,
> 		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
> 		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
> 		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
> @@ -231,7 +229,7 @@ static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
> 	if (!cmnd)
> 		return;
> 
> -	cmdinfo = (void *)&cmnd->SCp;
> +	cmdinfo = scsi_cmd_priv(cmnd);
> 
> 	if (cmdinfo->state & SUBMIT_CMD_URB)
> 		usb_free_urb(cmdinfo->cmd_urb);
> @@ -245,7 +243,7 @@ static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
> 
> static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
> {
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
> 
> 	lockdep_assert_held(&devinfo->lock);
> @@ -263,13 +261,13 @@ static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
> static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
> 			  unsigned direction)
> {
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	int err;
> 
> 	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
> 	err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
> 	if (err) {
> -		uas_add_work(cmdinfo);
> +		uas_add_work(cmnd);
> 	}
> }
> 
> @@ -329,7 +327,7 @@ static void uas_stat_cmplt(struct urb *urb)
> 	}
> 
> 	cmnd = devinfo->cmnd[idx];
> -	cmdinfo = (void *)&cmnd->SCp;
> +	cmdinfo = scsi_cmd_priv(cmnd);
> 
> 	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
> 		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
> @@ -394,7 +392,7 @@ static void uas_stat_cmplt(struct urb *urb)
> static void uas_data_cmplt(struct urb *urb)
> {
> 	struct scsi_cmnd *cmnd = urb->context;
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
> 	struct scsi_data_buffer *sdb = &cmnd->sdb;
> 	unsigned long flags;
> @@ -446,7 +444,7 @@ static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
> 				      enum dma_data_direction dir)
> {
> 	struct usb_device *udev = devinfo->udev;
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	struct urb *urb = usb_alloc_urb(0, gfp);
> 	struct scsi_data_buffer *sdb = &cmnd->sdb;
> 	unsigned int pipe = (dir == DMA_FROM_DEVICE)
> @@ -468,7 +466,7 @@ static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
> 				       struct scsi_cmnd *cmnd)
> {
> 	struct usb_device *udev = devinfo->udev;
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	struct urb *urb = usb_alloc_urb(0, gfp);
> 	struct sense_iu *iu;
> 
> @@ -496,7 +494,7 @@ static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
> {
> 	struct usb_device *udev = devinfo->udev;
> 	struct scsi_device *sdev = cmnd->device;
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	struct urb *urb = usb_alloc_urb(0, gfp);
> 	struct command_iu *iu;
> 	int len;
> @@ -558,7 +556,7 @@ static struct urb *uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
> static int uas_submit_urbs(struct scsi_cmnd *cmnd,
> 			   struct uas_dev_info *devinfo)
> {
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	struct urb *urb;
> 	int err;
> 
> @@ -637,12 +635,10 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd)
> {
> 	struct scsi_device *sdev = cmnd->device;
> 	struct uas_dev_info *devinfo = sdev->hostdata;
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	unsigned long flags;
> 	int idx, err;
> 
> -	BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
> -
> 	/* Re-check scsi_block_requests now that we've the host-lock */
> 	if (cmnd->device->host->host_self_blocked)
> 		return SCSI_MLQUEUE_DEVICE_BUSY;
> @@ -712,7 +708,7 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd)
> 			spin_unlock_irqrestore(&devinfo->lock, flags);
> 			return SCSI_MLQUEUE_DEVICE_BUSY;
> 		}
> -		uas_add_work(cmdinfo);
> +		uas_add_work(cmnd);
> 	}
> 
> 	devinfo->cmnd[idx] = cmnd;
> @@ -730,7 +726,7 @@ static DEF_SCSI_QCMD(uas_queuecommand)
>  */
> static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
> {
> -	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
> +	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
> 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
> 	struct urb *data_in_urb = NULL;
> 	struct urb *data_out_urb = NULL;
> @@ -910,6 +906,7 @@ static struct scsi_host_template uas_host_template = {
> 	.this_id = -1,
> 	.skip_settle_delay = 1,
> 	.dma_boundary = PAGE_SIZE - 1,
> +	.cmd_size = sizeof(struct uas_cmd_info),
> };
> 
> #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \

Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>

--
Himanshu Madhani	 Oracle Linux Engineering