Hi,
On 11/28/20 4:48 PM, Tom Yan wrote:
> Apparently the former (with the chosen dma_dev) may cause problem in certain
> case (e.g. where thunderbolt dock and intel iommu are involved). The error
> observed was:
>
> XHCI swiotlb buffer is full / DMAR: Device bounce map failed
>
> For now we retain the clamp for hw_max_sectors against the dma_max_mapping_size.
> Since the device/size for the clamp that is applied when the scsi request queue
> is initialized/allocated is different than the one used here, we invalidate the
> early clamping by making a fallback blk_queue_max_hw_sectors() call.
>
> Signed-off-by: Tom Yan <tom.ty89@xxxxxxxxx>
I can confirm that this fixes the network performance on a Lenovo Thunderbolt
dock generation 2, which uses an USB attach NIC.
With this patch added on top of 5.10-rc5 scp performance to another machine
on the local gbit LAN goes back from the regressed 1 MB/s to its original 100MB/s
as it should be:
Tested-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Regards,
Hans
> ---
> drivers/usb/storage/uas.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
> index c8a577309e8f..5db1325cea20 100644
> --- a/drivers/usb/storage/uas.c
> +++ b/drivers/usb/storage/uas.c
> @@ -843,18 +843,21 @@ static int uas_slave_alloc(struct scsi_device *sdev)
> static int uas_slave_configure(struct scsi_device *sdev)
> {
> struct uas_dev_info *devinfo = sdev->hostdata;
> - struct device *dev = sdev->host->dma_dev;
> + struct usb_device *udev = devinfo->udev;
>
> if (devinfo->flags & US_FL_MAX_SECTORS_64)
> blk_queue_max_hw_sectors(sdev->request_queue, 64);
> else if (devinfo->flags & US_FL_MAX_SECTORS_240)
> blk_queue_max_hw_sectors(sdev->request_queue, 240);
> - else if (devinfo->udev->speed >= USB_SPEED_SUPER)
> + else if (udev->speed >= USB_SPEED_SUPER)
> blk_queue_max_hw_sectors(sdev->request_queue, 2048);
> + else
> + blk_queue_max_hw_sectors(sdev->request_queue,
> + SCSI_DEFAULT_MAX_SECTORS);
>
> blk_queue_max_hw_sectors(sdev->request_queue,
> min_t(size_t, queue_max_hw_sectors(sdev->request_queue),
> - dma_max_mapping_size(dev) >> SECTOR_SHIFT));
> + dma_max_mapping_size(udev->bus->sysdev) >> SECTOR_SHIFT));
>
> if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
> sdev->no_report_opcodes = 1;
> @@ -1040,7 +1043,7 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
> shost->can_queue = devinfo->qdepth - 2;
>
> usb_set_intfdata(intf, shost);
> - result = scsi_add_host_with_dma(shost, &intf->dev, udev->bus->sysdev);
> + result = scsi_add_host(shost, &intf->dev);
> if (result)
> goto free_streams;
>
>
