svn commit: r353278 - releng/12.1/sys/dev/usb

[Hans Petter Selasky]

Author: hselasky
Date: Mon Oct  7 15:25:00 2019
New Revision: 353278
URL: https://svnweb.freebsd.org/changeset/base/353278

Log:
  MFS r353173:
  Increase the maximum user-space buffer size from 256kBytes to 32MBytes for
  libusb. This is useful for speeding up large data transfers while reducing
  the interrupt rate.
  
  Found at:	EuroBSDcon 2019
  Sponsored by:	Mellanox Technologies
  Approved by:	re (gjb)

Modified:
  releng/12.1/sys/dev/usb/usb_ioctl.h
Directory Properties:
  releng/12.1/   (props changed)

Modified: releng/12.1/sys/dev/usb/usb_ioctl.h
==============================================================================
--- releng/12.1/sys/dev/usb/usb_ioctl.h	Mon Oct  7 15:03:24 2019	(r353277)
+++ releng/12.1/sys/dev/usb/usb_ioctl.h	Mon Oct  7 15:25:00 2019	(r353278)
@@ -224,7 +224,7 @@ struct usb_fs_uninit {
 } USB_IOCTL_STRUCT_ALIGN(1);
 
 struct usb_fs_open {
-#define	USB_FS_MAX_BUFSIZE (1 << 18)
+#define	USB_FS_MAX_BUFSIZE (1 << 25)	/* 32 MBytes */
 	uint32_t max_bufsize;
 #define	USB_FS_MAX_FRAMES		(1U << 12)
 #define	USB_FS_MAX_FRAMES_PRE_SCALE	(1U << 31)	/* for ISOCHRONOUS transfers */