On 10.06.2022 17:33:35, Rhett Aultman wrote: > From: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx> > > When allocating URB memory with kmalloc(), drivers can simply set the > URB_FREE_BUFFER flag in urb::transfer_flags and that way, the memory > will be freed in the background when killing the URB (for example with > usb_kill_anchored_urbs()). > > However, there are no equivalent mechanism when allocating DMA memory > (with usb_alloc_coherent()). > > This patch adds a new flag: URB_FREE_COHERENT. Setting this flag will > cause the kernel to automatically call usb_free_coherent() on the > transfer buffer when the URB is killed, similarly to how > URB_FREE_BUFFER triggers a call to kfree(). > > In order to have all the flags in numerical order, URB_DIR_IN is > renumbered from 0x0200 to 0x0400 so that URB_FREE_COHERENT can reuse > value 0x0200. > > Co-developed-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx> > Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx> > Co-developed-by: Rhett Aultman <rhett.aultman@xxxxxxxxxxx> > Signed-off-by: Rhett Aultman <rhett.aultman@xxxxxxxxxxx> > Reviewed-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx> FWIW: Acked-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> This patch probably goes upstream via USB. Once this is in net I'll take the 2nd patch. regards, Marc -- Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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