usb: catch attempts to submit urbs with a vmalloc'd transfer buffer

Save someone else the debug cycles of figuring out why a driver's
transfer request is failing or causing undefined system behavior.
Buffers submitted for dma must come from GFP allocated / DMA-able
memory.

Return -EAGAIN matching the return value for dma_mapping_error() cases.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Dan Williams 2014-05-08 19:25:56 +03:00 committed by Greg Kroah-Hartman
parent 654a55d34f
commit 29d2fef8be
1 changed files with 3 additions and 0 deletions

View File

@ -1502,6 +1502,9 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
ret = -EAGAIN;
else
urb->transfer_flags |= URB_DMA_MAP_PAGE;
} else if (is_vmalloc_addr(urb->transfer_buffer)) {
WARN_ONCE(1, "transfer buffer not dma capable\n");
ret = -EAGAIN;
} else {
urb->transfer_dma = dma_map_single(
hcd->self.controller,