svn commit: r353175 - stable/10/sys/dev/usb

[Hans Petter Selasky]

Author: hselasky
Date: Mon Oct  7 08:13:49 2019
New Revision: 353175
URL: https://svnweb.freebsd.org/changeset/base/353175

Log:
  MFC r352555:
  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

Modified:
  stable/10/sys/dev/usb/usb_ioctl.h
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/dev/usb/usb_ioctl.h
==============================================================================
--- stable/10/sys/dev/usb/usb_ioctl.h	Mon Oct  7 08:13:10 2019	(r353174)
+++ stable/10/sys/dev/usb/usb_ioctl.h	Mon Oct  7 08:13:49 2019	(r353175)
@@ -218,7 +218,7 @@ 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 */