Don't trust that the reserved bits are always zero, also sanity check
the returned value.
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The cleanup path makes an effort to only perform an atomic read of the
64-bit completion address. However in the 32-bit case it does not
matter if we read the upper-32 and lower-32 non-atomically because the
upper-32 will always be zero.
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Provide some output for debugging the driver.
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Replace the current linked list munged into a ring with a native ring
buffer implementation. The benefit of this approach is reduced overhead
as many parameters can be derived from ring position with simple pointer
comparisons and descriptor allocation/freeing becomes just a
manipulation of head/tail pointers.
It requires a contiguous allocation for the software descriptor
information.
Since this arrangement is significantly different from the ioat1 chain,
move ioat2,3 support into its own file and header. Common routines are
exported from driver/dma/ioat/dma.[ch].
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams