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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/infiniband
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'Documentation/infiniband')
-rw-r--r--Documentation/infiniband/ipoib.txt56
-rw-r--r--Documentation/infiniband/sysfs.txt66
-rw-r--r--Documentation/infiniband/user_mad.txt99
3 files changed, 221 insertions, 0 deletions
diff --git a/Documentation/infiniband/ipoib.txt b/Documentation/infiniband/ipoib.txt
new file mode 100644
index 00000000000..18e184b5604
--- /dev/null
+++ b/Documentation/infiniband/ipoib.txt
@@ -0,0 +1,56 @@
+IP OVER INFINIBAND
+
+ The ib_ipoib driver is an implementation of the IP over InfiniBand
+ protocol as specified by the latest Internet-Drafts issued by the
+ IETF ipoib working group. It is a "native" implementation in the
+ sense of setting the interface type to ARPHRD_INFINIBAND and the
+ hardware address length to 20 (earlier proprietary implementations
+ masqueraded to the kernel as ethernet interfaces).
+
+Partitions and P_Keys
+
+ When the IPoIB driver is loaded, it creates one interface for each
+ port using the P_Key at index 0. To create an interface with a
+ different P_Key, write the desired P_Key into the main interface's
+ /sys/class/net/<intf name>/create_child file. For example:
+
+ echo 0x8001 > /sys/class/net/ib0/create_child
+
+ This will create an interface named ib0.8001 with P_Key 0x8001. To
+ remove a subinterface, use the "delete_child" file:
+
+ echo 0x8001 > /sys/class/net/ib0/delete_child
+
+ The P_Key for any interface is given by the "pkey" file, and the
+ main interface for a subinterface is in "parent."
+
+Debugging Information
+
+ By compiling the IPoIB driver with CONFIG_INFINIBAND_IPOIB_DEBUG set
+ to 'y', tracing messages are compiled into the driver. They are
+ turned on by setting the module parameters debug_level and
+ mcast_debug_level to 1. These parameters can be controlled at
+ runtime through files in /sys/module/ib_ipoib/.
+
+ CONFIG_INFINIBAND_IPOIB_DEBUG also enables the "ipoib_debugfs"
+ virtual filesystem. By mounting this filesystem, for example with
+
+ mkdir -p /ipoib_debugfs
+ mount -t ipoib_debugfs none /ipoib_debufs
+
+ it is possible to get statistics about multicast groups from the
+ files /ipoib_debugfs/ib0_mcg and so on.
+
+ The performance impact of this option is negligible, so it
+ is safe to enable this option with debug_level set to 0 for normal
+ operation.
+
+ CONFIG_INFINIBAND_IPOIB_DEBUG_DATA enables even more debug output in
+ the data path when data_debug_level is set to 1. However, even with
+ the output disabled, enabling this configuration option will affect
+ performance, because it adds tests to the fast path.
+
+References
+
+ IETF IP over InfiniBand (ipoib) Working Group
+ http://ietf.org/html.charters/ipoib-charter.html
diff --git a/Documentation/infiniband/sysfs.txt b/Documentation/infiniband/sysfs.txt
new file mode 100644
index 00000000000..ddd519b72ee
--- /dev/null
+++ b/Documentation/infiniband/sysfs.txt
@@ -0,0 +1,66 @@
+SYSFS FILES
+
+ For each InfiniBand device, the InfiniBand drivers create the
+ following files under /sys/class/infiniband/<device name>:
+
+ node_type - Node type (CA, switch or router)
+ node_guid - Node GUID
+ sys_image_guid - System image GUID
+
+ In addition, there is a "ports" subdirectory, with one subdirectory
+ for each port. For example, if mthca0 is a 2-port HCA, there will
+ be two directories:
+
+ /sys/class/infiniband/mthca0/ports/1
+ /sys/class/infiniband/mthca0/ports/2
+
+ (A switch will only have a single "0" subdirectory for switch port
+ 0; no subdirectory is created for normal switch ports)
+
+ In each port subdirectory, the following files are created:
+
+ cap_mask - Port capability mask
+ lid - Port LID
+ lid_mask_count - Port LID mask count
+ rate - Port data rate (active width * active speed)
+ sm_lid - Subnet manager LID for port's subnet
+ sm_sl - Subnet manager SL for port's subnet
+ state - Port state (DOWN, INIT, ARMED, ACTIVE or ACTIVE_DEFER)
+ phys_state - Port physical state (Sleep, Polling, LinkUp, etc)
+
+ There is also a "counters" subdirectory, with files
+
+ VL15_dropped
+ excessive_buffer_overrun_errors
+ link_downed
+ link_error_recovery
+ local_link_integrity_errors
+ port_rcv_constraint_errors
+ port_rcv_data
+ port_rcv_errors
+ port_rcv_packets
+ port_rcv_remote_physical_errors
+ port_rcv_switch_relay_errors
+ port_xmit_constraint_errors
+ port_xmit_data
+ port_xmit_discards
+ port_xmit_packets
+ symbol_error
+
+ Each of these files contains the corresponding value from the port's
+ Performance Management PortCounters attribute, as described in
+ section 16.1.3.5 of the InfiniBand Architecture Specification.
+
+ The "pkeys" and "gids" subdirectories contain one file for each
+ entry in the port's P_Key or GID table respectively. For example,
+ ports/1/pkeys/10 contains the value at index 10 in port 1's P_Key
+ table.
+
+MTHCA
+
+ The Mellanox HCA driver also creates the files:
+
+ hw_rev - Hardware revision number
+ fw_ver - Firmware version
+ hca_type - HCA type: "MT23108", "MT25208 (MT23108 compat mode)",
+ or "MT25208"
diff --git a/Documentation/infiniband/user_mad.txt b/Documentation/infiniband/user_mad.txt
new file mode 100644
index 00000000000..cae0c83f1ee
--- /dev/null
+++ b/Documentation/infiniband/user_mad.txt
@@ -0,0 +1,99 @@
+USERSPACE MAD ACCESS
+
+Device files
+
+ Each port of each InfiniBand device has a "umad" device and an
+ "issm" device attached. For example, a two-port HCA will have two
+ umad devices and two issm devices, while a switch will have one
+ device of each type (for switch port 0).
+
+Creating MAD agents
+
+ A MAD agent can be created by filling in a struct ib_user_mad_reg_req
+ and then calling the IB_USER_MAD_REGISTER_AGENT ioctl on a file
+ descriptor for the appropriate device file. If the registration
+ request succeeds, a 32-bit id will be returned in the structure.
+ For example:
+
+ struct ib_user_mad_reg_req req = { /* ... */ };
+ ret = ioctl(fd, IB_USER_MAD_REGISTER_AGENT, (char *) &req);
+ if (!ret)
+ my_agent = req.id;
+ else
+ perror("agent register");
+
+ Agents can be unregistered with the IB_USER_MAD_UNREGISTER_AGENT
+ ioctl. Also, all agents registered through a file descriptor will
+ be unregistered when the descriptor is closed.
+
+Receiving MADs
+
+ MADs are received using read(). The buffer passed to read() must be
+ large enough to hold at least one struct ib_user_mad. For example:
+
+ struct ib_user_mad mad;
+ ret = read(fd, &mad, sizeof mad);
+ if (ret != sizeof mad)
+ perror("read");
+
+ In addition to the actual MAD contents, the other struct ib_user_mad
+ fields will be filled in with information on the received MAD. For
+ example, the remote LID will be in mad.lid.
+
+ If a send times out, a receive will be generated with mad.status set
+ to ETIMEDOUT. Otherwise when a MAD has been successfully received,
+ mad.status will be 0.
+
+ poll()/select() may be used to wait until a MAD can be read.
+
+Sending MADs
+
+ MADs are sent using write(). The agent ID for sending should be
+ filled into the id field of the MAD, the destination LID should be
+ filled into the lid field, and so on. For example:
+
+ struct ib_user_mad mad;
+
+ /* fill in mad.data */
+
+ mad.id = my_agent; /* req.id from agent registration */
+ mad.lid = my_dest; /* in network byte order... */
+ /* etc. */
+
+ ret = write(fd, &mad, sizeof mad);
+ if (ret != sizeof mad)
+ perror("write");
+
+Setting IsSM Capability Bit
+
+ To set the IsSM capability bit for a port, simply open the
+ corresponding issm device file. If the IsSM bit is already set,
+ then the open call will block until the bit is cleared (or return
+ immediately with errno set to EAGAIN if the O_NONBLOCK flag is
+ passed to open()). The IsSM bit will be cleared when the issm file
+ is closed. No read, write or other operations can be performed on
+ the issm file.
+
+/dev files
+
+ To create the appropriate character device files automatically with
+ udev, a rule like
+
+ KERNEL="umad*", NAME="infiniband/%k"
+ KERNEL="issm*", NAME="infiniband/%k"
+
+ can be used. This will create device nodes named
+
+ /dev/infiniband/umad0
+ /dev/infiniband/issm0
+
+ for the first port, and so on. The InfiniBand device and port
+ associated with these devices can be determined from the files
+
+ /sys/class/infiniband_mad/umad0/ibdev
+ /sys/class/infiniband_mad/umad0/port
+
+ and
+
+ /sys/class/infiniband_mad/issm0/ibdev
+ /sys/class/infiniband_mad/issm0/port