Commit Graph

3 Commits

Author SHA1 Message Date
Alexander Schmidt 6773f079b7 IB/ehca: Discard double CQE for one WR
Under rare circumstances, the ehca hardware might erroneously generate
two CQEs for the same WQE, which is not compliant to the IB spec and
will cause unpredictable errors like memory being freed twice. To
avoid this problem, the driver needs to detect the second CQE and
discard it.

For this purpose, introduce an array holding as many elements as the
SQ of the QP, called sq_map. Each sq_map entry stores a "reported"
flag for one WQE in the SQ. When a work request is posted to the SQ,
the respective "reported" flag is set to zero. After the arrival of a
CQE, the flag is set to 1, which allows to detect the occurence of a
second CQE.

The mapping between WQE / CQE and the corresponding sq_map element is
implemented by replacing the lowest 16 Bits of the wr_id with the
index in the queue map. The original 16 Bits are stored in the sq_map
entry and are restored when the CQE is passed to the application.

Signed-off-by: Alexander Schmidt <alexs@linux.vnet.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2008-08-12 11:34:59 -07:00
Hoang-Nam Nguyen 2b94397adc IB/ehca: Fix warnings issued by checkpatch.pl
Run the existing ehca code through checkpatch.pl and clean up the
worst of the coding style violations.

Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-07-17 18:37:40 -07:00
Heiko J Schick fab97220c9 IB/ehca: Add driver for IBM eHCA InfiniBand adapters
Add a driver for IBM GX bus InfiniBand adapters, which are usable with
some pSeries/System p systems.

Signed-off-by: Heiko J Schick <schickhj.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-09-22 15:22:22 -07:00