linux/drivers/infiniband/hw
Jack Morgenstein ea54b10c77 IB/mlx4: Use multiple WQ blocks to post smaller send WQEs
ConnectX HCA supports shrinking WQEs, so that a single work request
can be made of multiple units of wqe_shift.  This way, WRs can differ
in size, and do not have to be a power of 2 in size, saving memory and
speeding up send WR posting.  Unfortunately, if we do this then the
wqe_index field in CQEs can't be used to look up the WR ID anymore, so
our implementation does this only if selective signaling is off.

Further, on 32-bit platforms, we can't use vmap() to make the QP
buffer virtually contigious. Thus we have to use constant-sized WRs to
make sure a WR is always fully within a single page-sized chunk.

Finally, we use WRs with the NOP opcode to avoid wrapping around the
queue buffer in the middle of posting a WR, and we set the
NoErrorCompletion bit to avoid getting completions with error for NOP
WRs.  However, NEC is only supported starting with firmware 2.2.232,
so we use constant-sized WRs for older firmware.  And, since MLX QPs
only support SEND, we use constant-sized WRs in this case.

When stamping during NOP posting, do stamping following setting of the
NOP WQE valid bit.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2008-02-08 13:30:02 -08:00
..
amso1100 [NET]: Nuke SET_MODULE_OWNER macro. 2007-10-10 16:51:13 -07:00
cxgb3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.25 2008-01-29 22:54:01 +11:00
ehca IB/ehca: Add PMA support 2008-02-04 20:20:42 -08:00
ipath IB/ipath: Remove unnecessary cast 2008-01-25 14:17:46 -08:00
mlx4 IB/mlx4: Use multiple WQ blocks to post smaller send WQEs 2008-02-08 13:30:02 -08:00
mthca IB/mthca: Return proper error codes from mthca_fmr_alloc() 2008-02-04 20:20:44 -08:00
nes RDMA/nes: Add a driver for NetEffect RNICs 2008-02-04 20:20:45 -08:00