diff options
Diffstat (limited to 'Documentation/infiniband/user_mad.txt')
| -rw-r--r-- | Documentation/infiniband/user_mad.txt | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/Documentation/infiniband/user_mad.txt b/Documentation/infiniband/user_mad.txt index 750fe5e80eb..8a366959f5c 100644 --- a/Documentation/infiniband/user_mad.txt +++ b/Documentation/infiniband/user_mad.txt @@ -91,6 +91,28 @@ Sending MADs if (ret != sizeof *mad + mad_length) perror("write"); +Transaction IDs + + Users of the umad devices can use the lower 32 bits of the + transaction ID field (that is, the least significant half of the + field in network byte order) in MADs being sent to match + request/response pairs. The upper 32 bits are reserved for use by + the kernel and will be overwritten before a MAD is sent. + +P_Key Index Handling + + The old ib_umad interface did not allow setting the P_Key index for + MADs that are sent and did not provide a way for obtaining the P_Key + index of received MADs. A new layout for struct ib_user_mad_hdr + with a pkey_index member has been defined; however, to preserve + binary compatibility with older applications, this new layout will + not be used unless the IB_USER_MAD_ENABLE_PKEY ioctl is called + before a file descriptor is used for anything else. + + In September 2008, the IB_USER_MAD_ABI_VERSION will be incremented + to 6, the new layout of struct ib_user_mad_hdr will be used by + default, and the IB_USER_MAD_ENABLE_PKEY ioctl will be removed. + Setting IsSM Capability Bit To set the IsSM capability bit for a port, simply open the @@ -106,8 +128,8 @@ Setting IsSM Capability Bit To create the appropriate character device files automatically with udev, a rule like - KERNEL="umad*", NAME="infiniband/%k" - KERNEL="issm*", NAME="infiniband/%k" + KERNEL=="umad*", NAME="infiniband/%k" + KERNEL=="issm*", NAME="infiniband/%k" can be used. This will create device nodes named |