USB: storage: set bounce limit for non-DMA-capable host controllers

This patch (as1175) makes usb-storage set a SCSI device's
request-queue bounce limit such that all buffers will be located in
addressable memory (i.e., not in high memory) if the host controller's
dma_mask is NULL.  This is necessary when the host controller doesn't
support DMA: If a buffer is in high memory then the both the virtual
and DMA addresses produced by the scatter-gather library will be NULL,
preventing the HCD from accessing the buffer's data.

In particular, the isp1760 driver needs this when used on a system
with more than 1 GB of memory.

Signed-off-by: Alan Stern <[email protected]>
CC: Matthew Dharm <[email protected]>
Acked-by: Jens Axboe <[email protected]>
Tested-by: Thomas Hommel <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

0 files changed, 0 insertions, 0 deletions