Commit Graph

3 Commits

Author SHA1 Message Date
Eric Biggers
d40a094644 misc: mic: fix incorrect use of error codes in SCIF DMA driver
The error code passed to ERR_PTR() always should be negated.  Also, the
return value of scif_add_mmu_notifier() was never checked.

Signed-off-by: Eric Biggers <ebiggers3@gmail.com>
Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07 21:25:50 -08:00
Geliang Tang
0d0ce9c00b misc: mic/scif: use list_next_entry instead of list_entry_next
list_next_entry has been defined in list.h, so I replace list_entry_next
with it.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07 21:25:50 -08:00
Sudeep Dutt
7cc31cd277 misc: mic: SCIF DMA and CPU copy interface
SCIF allows users to read from or write to registered remote memory
via CPU copies or DMA. The API verifies that both local and remote
windows are valid before initiating the CPU or DMA transfers. SCIF has
optimized algorithms for handling byte aligned as well as cache line
aligned DMA engines. A registration cache is maintained to avoid the
overhead of pinning pages repeatedly if buffers are reused. The
registration cache is invalidated upon receipt of MMU notifier
callbacks.  SCIF windows are destroyed and the pages are unpinned only
once all prior DMAs initiated using that window are drained. Users can
request synchronous DMA operations as well as tail byte ordering if
required. CPU copies are always performed synchronously.

Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Nikhil Rao <nikhil.rao@intel.com>
Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 12:54:54 +01:00