Commit 97162a1e authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab Committed by Jason Gunthorpe

docs: infiniband: convert docs to ReST and rename to *.rst

The InfiniBand docs are plain text with no markups.  So, all we needed to
do were to add the title markups and some markup sequences in order to
properly parse tables, lists and literal blocks.

At its new index.rst, let's add a :orphan: while this is not linked to the
main index.rst file, in order to avoid build warnings.
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: default avatarJason Gunthorpe <jgg@mellanox.com>
parent b417c087
INFINIBAND MIDLAYER LOCKING ===========================
InfiniBand Midlayer Locking
===========================
This guide is an attempt to make explicit the locking assumptions This guide is an attempt to make explicit the locking assumptions
made by the InfiniBand midlayer. It describes the requirements on made by the InfiniBand midlayer. It describes the requirements on
...@@ -6,45 +8,47 @@ INFINIBAND MIDLAYER LOCKING ...@@ -6,45 +8,47 @@ INFINIBAND MIDLAYER LOCKING
protocols that use the midlayer. protocols that use the midlayer.
Sleeping and interrupt context Sleeping and interrupt context
==============================
With the following exceptions, a low-level driver implementation of With the following exceptions, a low-level driver implementation of
all of the methods in struct ib_device may sleep. The exceptions all of the methods in struct ib_device may sleep. The exceptions
are any methods from the list: are any methods from the list:
create_ah - create_ah
modify_ah - modify_ah
query_ah - query_ah
destroy_ah - destroy_ah
post_send - post_send
post_recv - post_recv
poll_cq - poll_cq
req_notify_cq - req_notify_cq
map_phys_fmr - map_phys_fmr
which may not sleep and must be callable from any context. which may not sleep and must be callable from any context.
The corresponding functions exported to upper level protocol The corresponding functions exported to upper level protocol
consumers: consumers:
ib_create_ah - ib_create_ah
ib_modify_ah - ib_modify_ah
ib_query_ah - ib_query_ah
ib_destroy_ah - ib_destroy_ah
ib_post_send - ib_post_send
ib_post_recv - ib_post_recv
ib_req_notify_cq - ib_req_notify_cq
ib_map_phys_fmr - ib_map_phys_fmr
are therefore safe to call from any context. are therefore safe to call from any context.
In addition, the function In addition, the function
ib_dispatch_event - ib_dispatch_event
used by low-level drivers to dispatch asynchronous events through used by low-level drivers to dispatch asynchronous events through
the midlayer is also safe to call from any context. the midlayer is also safe to call from any context.
Reentrancy Reentrancy
----------
All of the methods in struct ib_device exported by a low-level All of the methods in struct ib_device exported by a low-level
driver must be fully reentrant. The low-level driver is required to driver must be fully reentrant. The low-level driver is required to
...@@ -62,6 +66,7 @@ Reentrancy ...@@ -62,6 +66,7 @@ Reentrancy
information between different calls of ib_poll_cq() is not defined. information between different calls of ib_poll_cq() is not defined.
Callbacks Callbacks
---------
A low-level driver must not perform a callback directly from the A low-level driver must not perform a callback directly from the
same callchain as an ib_device method call. For example, it is not same callchain as an ib_device method call. For example, it is not
...@@ -74,18 +79,18 @@ Callbacks ...@@ -74,18 +79,18 @@ Callbacks
completion event handlers for the same CQ are not called completion event handlers for the same CQ are not called
simultaneously. The driver must guarantee that only one CQ event simultaneously. The driver must guarantee that only one CQ event
handler for a given CQ is running at a time. In other words, the handler for a given CQ is running at a time. In other words, the
following situation is not allowed: following situation is not allowed::
CPU1 CPU2 CPU1 CPU2
low-level driver -> low-level driver ->
consumer CQ event callback: consumer CQ event callback:
/* ... */ /* ... */
ib_req_notify_cq(cq, ...); ib_req_notify_cq(cq, ...);
low-level driver -> low-level driver ->
/* ... */ consumer CQ event callback: /* ... */ consumer CQ event callback:
/* ... */ /* ... */
return from CQ event handler return from CQ event handler
The context in which completion event and asynchronous event The context in which completion event and asynchronous event
callbacks run is not defined. Depending on the low-level driver, it callbacks run is not defined. Depending on the low-level driver, it
...@@ -93,6 +98,7 @@ Callbacks ...@@ -93,6 +98,7 @@ Callbacks
Upper level protocol consumers may not sleep in a callback. Upper level protocol consumers may not sleep in a callback.
Hot-plug Hot-plug
--------
A low-level driver announces that a device is ready for use by A low-level driver announces that a device is ready for use by
consumers when it calls ib_register_device(), all initialization consumers when it calls ib_register_device(), all initialization
......
:orphan:
==========
InfiniBand
==========
.. toctree::
:maxdepth: 1
core_locking
ipoib
opa_vnic
sysfs
tag_matching
user_mad
user_verbs
.. only:: subproject and html
Indices
=======
* :ref:`genindex`
IP OVER INFINIBAND ==================
IP over InfiniBand
==================
The ib_ipoib driver is an implementation of the IP over InfiniBand The ib_ipoib driver is an implementation of the IP over InfiniBand
protocol as specified by RFC 4391 and 4392, issued by the IETF ipoib protocol as specified by RFC 4391 and 4392, issued by the IETF ipoib
...@@ -8,16 +10,17 @@ IP OVER INFINIBAND ...@@ -8,16 +10,17 @@ IP OVER INFINIBAND
masqueraded to the kernel as ethernet interfaces). masqueraded to the kernel as ethernet interfaces).
Partitions and P_Keys Partitions and P_Keys
=====================
When the IPoIB driver is loaded, it creates one interface for each 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 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 different P_Key, write the desired P_Key into the main interface's
/sys/class/net/<intf name>/create_child file. For example: /sys/class/net/<intf name>/create_child file. For example::
echo 0x8001 > /sys/class/net/ib0/create_child echo 0x8001 > /sys/class/net/ib0/create_child
This will create an interface named ib0.8001 with P_Key 0x8001. To This will create an interface named ib0.8001 with P_Key 0x8001. To
remove a subinterface, use the "delete_child" file: remove a subinterface, use the "delete_child" file::
echo 0x8001 > /sys/class/net/ib0/delete_child echo 0x8001 > /sys/class/net/ib0/delete_child
...@@ -28,6 +31,7 @@ Partitions and P_Keys ...@@ -28,6 +31,7 @@ Partitions and P_Keys
rtnl_link_ops, where children created using either way behave the same. rtnl_link_ops, where children created using either way behave the same.
Datagram vs Connected modes Datagram vs Connected modes
===========================
The IPoIB driver supports two modes of operation: datagram and The IPoIB driver supports two modes of operation: datagram and
connected. The mode is set and read through an interface's connected. The mode is set and read through an interface's
...@@ -51,6 +55,7 @@ Datagram vs Connected modes ...@@ -51,6 +55,7 @@ Datagram vs Connected modes
networking stack to use the smaller UD MTU for these neighbours. networking stack to use the smaller UD MTU for these neighbours.
Stateless offloads Stateless offloads
==================
If the IB HW supports IPoIB stateless offloads, IPoIB advertises If the IB HW supports IPoIB stateless offloads, IPoIB advertises
TCP/IP checksum and/or Large Send (LSO) offloading capability to the TCP/IP checksum and/or Large Send (LSO) offloading capability to the
...@@ -60,9 +65,10 @@ Stateless offloads ...@@ -60,9 +65,10 @@ Stateless offloads
on/off using ethtool calls. Currently LRO is supported only for on/off using ethtool calls. Currently LRO is supported only for
checksum offload capable devices. checksum offload capable devices.
Stateless offloads are supported only in datagram mode. Stateless offloads are supported only in datagram mode.
Interrupt moderation Interrupt moderation
====================
If the underlying IB device supports CQ event moderation, one can If the underlying IB device supports CQ event moderation, one can
use ethtool to set interrupt mitigation parameters and thus reduce use ethtool to set interrupt mitigation parameters and thus reduce
...@@ -71,6 +77,7 @@ Interrupt moderation ...@@ -71,6 +77,7 @@ Interrupt moderation
moderation is supported. moderation is supported.
Debugging Information Debugging Information
=====================
By compiling the IPoIB driver with CONFIG_INFINIBAND_IPOIB_DEBUG set By compiling the IPoIB driver with CONFIG_INFINIBAND_IPOIB_DEBUG set
to 'y', tracing messages are compiled into the driver. They are to 'y', tracing messages are compiled into the driver. They are
...@@ -79,7 +86,7 @@ Debugging Information ...@@ -79,7 +86,7 @@ Debugging Information
runtime through files in /sys/module/ib_ipoib/. runtime through files in /sys/module/ib_ipoib/.
CONFIG_INFINIBAND_IPOIB_DEBUG also enables files in the debugfs CONFIG_INFINIBAND_IPOIB_DEBUG also enables files in the debugfs
virtual filesystem. By mounting this filesystem, for example with virtual filesystem. By mounting this filesystem, for example with::
mount -t debugfs none /sys/kernel/debug mount -t debugfs none /sys/kernel/debug
...@@ -96,10 +103,13 @@ Debugging Information ...@@ -96,10 +103,13 @@ Debugging Information
performance, because it adds tests to the fast path. performance, because it adds tests to the fast path.
References References
==========
Transmission of IP over InfiniBand (IPoIB) (RFC 4391) Transmission of IP over InfiniBand (IPoIB) (RFC 4391)
http://ietf.org/rfc/rfc4391.txt http://ietf.org/rfc/rfc4391.txt
IP over InfiniBand (IPoIB) Architecture (RFC 4392) IP over InfiniBand (IPoIB) Architecture (RFC 4392)
http://ietf.org/rfc/rfc4392.txt http://ietf.org/rfc/rfc4392.txt
IP over InfiniBand: Connected Mode (RFC 4755) IP over InfiniBand: Connected Mode (RFC 4755)
http://ietf.org/rfc/rfc4755.txt http://ietf.org/rfc/rfc4755.txt
=================================================================
Intel Omni-Path (OPA) Virtual Network Interface Controller (VNIC)
=================================================================
Intel Omni-Path (OPA) Virtual Network Interface Controller (VNIC) feature Intel Omni-Path (OPA) Virtual Network Interface Controller (VNIC) feature
supports Ethernet functionality over Omni-Path fabric by encapsulating supports Ethernet functionality over Omni-Path fabric by encapsulating
the Ethernet packets between HFI nodes. the Ethernet packets between HFI nodes.
...@@ -17,70 +21,72 @@ an independent Ethernet network. The configuration is performed by an ...@@ -17,70 +21,72 @@ an independent Ethernet network. The configuration is performed by an
Ethernet Manager (EM) which is part of the trusted Fabric Manager (FM) Ethernet Manager (EM) which is part of the trusted Fabric Manager (FM)
application. HFI nodes can have multiple VNICs each connected to a application. HFI nodes can have multiple VNICs each connected to a
different virtual Ethernet switch. The below diagram presents a case different virtual Ethernet switch. The below diagram presents a case
of two virtual Ethernet switches with two HFI nodes. of two virtual Ethernet switches with two HFI nodes::
+-------------------+ +-------------------+
| Subnet/ | | Subnet/ |
| Ethernet | | Ethernet |
| Manager | | Manager |
+-------------------+ +-------------------+
/ / / /
/ / / /
/ / / /
/ / / /
+-----------------------------+ +------------------------------+ +-----------------------------+ +------------------------------+
| Virtual Ethernet Switch | | Virtual Ethernet Switch | | Virtual Ethernet Switch | | Virtual Ethernet Switch |
| +---------+ +---------+ | | +---------+ +---------+ | | +---------+ +---------+ | | +---------+ +---------+ |
| | VPORT | | VPORT | | | | VPORT | | VPORT | | | | VPORT | | VPORT | | | | VPORT | | VPORT | |
+--+---------+----+---------+-+ +-+---------+----+---------+---+ +--+---------+----+---------+-+ +-+---------+----+---------+---+
| \ / | | \ / |
| \ / | | \ / |
| \/ | | \/ |
| / \ | | / \ |
| / \ | | / \ |
+-----------+------------+ +-----------+------------+ +-----------+------------+ +-----------+------------+
| VNIC | VNIC | | VNIC | VNIC | | VNIC | VNIC | | VNIC | VNIC |
+-----------+------------+ +-----------+------------+ +-----------+------------+ +-----------+------------+
| HFI | | HFI | | HFI | | HFI |
+------------------------+ +------------------------+ +------------------------+ +------------------------+
The Omni-Path encapsulated Ethernet packet format is as described below. The Omni-Path encapsulated Ethernet packet format is as described below.
Bits Field ==================== ================================
------------------------------------ Bits Field
==================== ================================
Quad Word 0: Quad Word 0:
0-19 SLID (lower 20 bits) 0-19 SLID (lower 20 bits)
20-30 Length (in Quad Words) 20-30 Length (in Quad Words)
31 BECN bit 31 BECN bit
32-51 DLID (lower 20 bits) 32-51 DLID (lower 20 bits)
52-56 SC (Service Class) 52-56 SC (Service Class)
57-59 RC (Routing Control) 57-59 RC (Routing Control)
60 FECN bit 60 FECN bit
61-62 L2 (=10, 16B format) 61-62 L2 (=10, 16B format)
63 LT (=1, Link Transfer Head Flit) 63 LT (=1, Link Transfer Head Flit)
Quad Word 1: Quad Word 1:
0-7 L4 type (=0x78 ETHERNET) 0-7 L4 type (=0x78 ETHERNET)
8-11 SLID[23:20] 8-11 SLID[23:20]
12-15 DLID[23:20] 12-15 DLID[23:20]
16-31 PKEY 16-31 PKEY
32-47 Entropy 32-47 Entropy
48-63 Reserved 48-63 Reserved
Quad Word 2: Quad Word 2:
0-15 Reserved 0-15 Reserved
16-31 L4 header 16-31 L4 header
32-63 Ethernet Packet 32-63 Ethernet Packet
Quad Words 3 to N-1: Quad Words 3 to N-1:
0-63 Ethernet packet (pad extended) 0-63 Ethernet packet (pad extended)
Quad Word N (last): Quad Word N (last):
0-23 Ethernet packet (pad extended) 0-23 Ethernet packet (pad extended)
24-55 ICRC 24-55 ICRC
56-61 Tail 56-61 Tail
62-63 LT (=01, Link Transfer Tail Flit) 62-63 LT (=01, Link Transfer Tail Flit)
==================== ================================
Ethernet packet is padded on the transmit side to ensure that the VNIC OPA Ethernet packet is padded on the transmit side to ensure that the VNIC OPA
packet is quad word aligned. The 'Tail' field contains the number of bytes packet is quad word aligned. The 'Tail' field contains the number of bytes
...@@ -123,7 +129,7 @@ operation. It also handles the encapsulation of Ethernet packets with an ...@@ -123,7 +129,7 @@ operation. It also handles the encapsulation of Ethernet packets with an
Omni-Path header in the transmit path. For each VNIC interface, the Omni-Path header in the transmit path. For each VNIC interface, the
information required for encapsulation is configured by the EM via VEMA MAD information required for encapsulation is configured by the EM via VEMA MAD
interface. It also passes any control information to the HW dependent driver interface. It also passes any control information to the HW dependent driver
by invoking the RDMA netdev control operations. by invoking the RDMA netdev control operations::
+-------------------+ +----------------------+ +-------------------+ +----------------------+
| | | Linux | | | | Linux |
......
SYSFS FILES ===========
Sysfs files
===========
The sysfs interface has moved to The sysfs interface has moved to
Documentation/ABI/stable/sysfs-class-infiniband. Documentation/ABI/stable/sysfs-class-infiniband.
==================
Tag matching logic Tag matching logic
==================
The MPI standard defines a set of rules, known as tag-matching, for matching The MPI standard defines a set of rules, known as tag-matching, for matching
source send operations to destination receives. The following parameters must source send operations to destination receives. The following parameters must
match the following source and destination parameters: match the following source and destination parameters:
* Communicator * Communicator
* User tag - wild card may be specified by the receiver * User tag - wild card may be specified by the receiver
* Source rank – wild car may be specified by the receiver * Source rank – wild car may be specified by the receiver
* Destination rank – wild * Destination rank – wild
The ordering rules require that when more than one pair of send and receive The ordering rules require that when more than one pair of send and receive
message envelopes may match, the pair that includes the earliest posted-send message envelopes may match, the pair that includes the earliest posted-send
and the earliest posted-receive is the pair that must be used to satisfy the and the earliest posted-receive is the pair that must be used to satisfy the
...@@ -35,6 +39,7 @@ the header to initiate an RDMA READ operation directly to the matching buffer. ...@@ -35,6 +39,7 @@ the header to initiate an RDMA READ operation directly to the matching buffer.
A fin message needs to be received in order for the buffer to be reused. A fin message needs to be received in order for the buffer to be reused.
Tag matching implementation Tag matching implementation
===========================
There are two types of matching objects used, the posted receive list and the There are two types of matching objects used, the posted receive list and the
unexpected message list. The application posts receive buffers through calls unexpected message list. The application posts receive buffers through calls
......
USERSPACE MAD ACCESS ====================
Userspace MAD access
====================
Device files Device files
============
Each port of each InfiniBand device has a "umad" device and an Each port of each InfiniBand device has a "umad" device and an
"issm" device attached. For example, a two-port HCA will have two "issm" device attached. For example, a two-port HCA will have two
...@@ -8,12 +11,13 @@ Device files ...@@ -8,12 +11,13 @@ Device files
device of each type (for switch port 0). device of each type (for switch port 0).
Creating MAD agents Creating MAD agents
===================
A MAD agent can be created by filling in a struct ib_user_mad_reg_req 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 and then calling the IB_USER_MAD_REGISTER_AGENT ioctl on a file
descriptor for the appropriate device file. If the registration descriptor for the appropriate device file. If the registration
request succeeds, a 32-bit id will be returned in the structure. request succeeds, a 32-bit id will be returned in the structure.
For example: For example::
struct ib_user_mad_reg_req req = { /* ... */ }; struct ib_user_mad_reg_req req = { /* ... */ };
ret = ioctl(fd, IB_USER_MAD_REGISTER_AGENT, (char *) &req); ret = ioctl(fd, IB_USER_MAD_REGISTER_AGENT, (char *) &req);
...@@ -26,12 +30,14 @@ Creating MAD agents ...@@ -26,12 +30,14 @@ Creating MAD agents
ioctl. Also, all agents registered through a file descriptor will ioctl. Also, all agents registered through a file descriptor will
be unregistered when the descriptor is closed. be unregistered when the descriptor is closed.
2014 -- a new registration ioctl is now provided which allows additional 2014
a new registration ioctl is now provided which allows additional
fields to be provided during registration. fields to be provided during registration.
Users of this registration call are implicitly setting the use of Users of this registration call are implicitly setting the use of
pkey_index (see below). pkey_index (see below).
Receiving MADs Receiving MADs
==============
MADs are received using read(). The receive side now supports MADs are received using read(). The receive side now supports
RMPP. The buffer passed to read() must be at least one RMPP. The buffer passed to read() must be at least one
...@@ -41,7 +47,8 @@ Receiving MADs ...@@ -41,7 +47,8 @@ Receiving MADs
MAD (RMPP), the errno is set to ENOSPC and the length of the MAD (RMPP), the errno is set to ENOSPC and the length of the
buffer needed is set in mad.length. buffer needed is set in mad.length.
Example for normal MAD (non RMPP) reads: Example for normal MAD (non RMPP) reads::
struct ib_user_mad *mad; struct ib_user_mad *mad;
mad = malloc(sizeof *mad + 256); mad = malloc(sizeof *mad + 256);
ret = read(fd, mad, sizeof *mad + 256); ret = read(fd, mad, sizeof *mad + 256);
...@@ -50,7 +57,8 @@ Receiving MADs ...@@ -50,7 +57,8 @@ Receiving MADs
free(mad); free(mad);
} }
Example for RMPP reads: Example for RMPP reads::
struct ib_user_mad *mad; struct ib_user_mad *mad;
mad = malloc(sizeof *mad + 256); mad = malloc(sizeof *mad + 256);
ret = read(fd, mad, sizeof *mad + 256); ret = read(fd, mad, sizeof *mad + 256);
...@@ -76,11 +84,12 @@ Receiving MADs ...@@ -76,11 +84,12 @@ Receiving MADs
poll()/select() may be used to wait until a MAD can be read. poll()/select() may be used to wait until a MAD can be read.
Sending MADs Sending MADs
============
MADs are sent using write(). The agent ID for sending should be 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 id field of the MAD, the destination LID should be
filled into the lid field, and so on. The send side does support filled into the lid field, and so on. The send side does support
RMPP so arbitrary length MAD can be sent. For example: RMPP so arbitrary length MAD can be sent. For example::
struct ib_user_mad *mad; struct ib_user_mad *mad;
...@@ -97,6 +106,7 @@ Sending MADs ...@@ -97,6 +106,7 @@ Sending MADs
perror("write"); perror("write");
Transaction IDs Transaction IDs
===============
Users of the umad devices can use the lower 32 bits of the Users of the umad devices can use the lower 32 bits of the
transaction ID field (that is, the least significant half of the transaction ID field (that is, the least significant half of the
...@@ -105,6 +115,7 @@ Transaction IDs ...@@ -105,6 +115,7 @@ Transaction IDs
the kernel and will be overwritten before a MAD is sent. the kernel and will be overwritten before a MAD is sent.
P_Key Index Handling P_Key Index Handling
====================
The old ib_umad interface did not allow setting the P_Key index for 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 MADs that are sent and did not provide a way for obtaining the P_Key
...@@ -119,6 +130,7 @@ P_Key Index Handling ...@@ -119,6 +130,7 @@ P_Key Index Handling
default, and the IB_USER_MAD_ENABLE_PKEY ioctl will be removed. default, and the IB_USER_MAD_ENABLE_PKEY ioctl will be removed.
Setting IsSM Capability Bit Setting IsSM Capability Bit
===========================
To set the IsSM capability bit for a port, simply open the To set the IsSM capability bit for a port, simply open the
corresponding issm device file. If the IsSM bit is already set, corresponding issm device file. If the IsSM bit is already set,
...@@ -129,25 +141,26 @@ Setting IsSM Capability Bit ...@@ -129,25 +141,26 @@ Setting IsSM Capability Bit
the issm file. the issm file.
/dev files /dev files
==========
To create the appropriate character device files automatically with To create the appropriate character device files automatically with
udev, a rule like udev, a rule like::
KERNEL=="umad*", NAME="infiniband/%k" KERNEL=="umad*", NAME="infiniband/%k"
KERNEL=="issm*", NAME="infiniband/%k" KERNEL=="issm*", NAME="infiniband/%k"
can be used. This will create device nodes named can be used. This will create device nodes named::
/dev/infiniband/umad0 /dev/infiniband/umad0
/dev/infiniband/issm0 /dev/infiniband/issm0
for the first port, and so on. The InfiniBand device and port for the first port, and so on. The InfiniBand device and port
associated with these devices can be determined from the files associated with these devices can be determined from the files::
/sys/class/infiniband_mad/umad0/ibdev /sys/class/infiniband_mad/umad0/ibdev
/sys/class/infiniband_mad/umad0/port /sys/class/infiniband_mad/umad0/port
and and::
/sys/class/infiniband_mad/issm0/ibdev /sys/class/infiniband_mad/issm0/ibdev
/sys/class/infiniband_mad/issm0/port /sys/class/infiniband_mad/issm0/port
USERSPACE VERBS ACCESS ======================
Userspace verbs access
======================
The ib_uverbs module, built by enabling CONFIG_INFINIBAND_USER_VERBS, The ib_uverbs module, built by enabling CONFIG_INFINIBAND_USER_VERBS,
enables direct userspace access to IB hardware via "verbs," as enables direct userspace access to IB hardware via "verbs," as
...@@ -13,6 +15,7 @@ USERSPACE VERBS ACCESS ...@@ -13,6 +15,7 @@ USERSPACE VERBS ACCESS
libmthca userspace driver be installed. libmthca userspace driver be installed.
User-kernel communication User-kernel communication
=========================
Userspace communicates with the kernel for slow path, resource Userspace communicates with the kernel for slow path, resource
management operations via the /dev/infiniband/uverbsN character management operations via the /dev/infiniband/uverbsN character
...@@ -28,6 +31,7 @@ User-kernel communication ...@@ -28,6 +31,7 @@ User-kernel communication
system call. system call.
Resource management Resource management
===================
Since creation and destruction of all IB resources is done by Since creation and destruction of all IB resources is done by
commands passed through a file descriptor, the kernel can keep track commands passed through a file descriptor, the kernel can keep track
...@@ -41,6 +45,7 @@ Resource management ...@@ -41,6 +45,7 @@ Resource management
prevent one process from touching another process's resources. prevent one process from touching another process's resources.
Memory pinning Memory pinning
==============
Direct userspace I/O requires that memory regions that are potential Direct userspace I/O requires that memory regions that are potential
I/O targets be kept resident at the same physical address. The I/O targets be kept resident at the same physical address. The
...@@ -54,13 +59,14 @@ Memory pinning ...@@ -54,13 +59,14 @@ Memory pinning
number of pages pinned by a process. number of pages pinned by a process.
/dev files /dev files
==========
To create the appropriate character device files automatically with To create the appropriate character device files automatically with
udev, a rule like udev, a rule like::
KERNEL=="uverbs*", NAME="infiniband/%k" KERNEL=="uverbs*", NAME="infiniband/%k"
can be used. This will create device nodes named can be used. This will create device nodes named::
/dev/infiniband/uverbs0 /dev/infiniband/uverbs0
......
...@@ -745,7 +745,7 @@ static int ib_umad_reg_agent(struct ib_umad_file *file, void __user *arg, ...@@ -745,7 +745,7 @@ static int ib_umad_reg_agent(struct ib_umad_file *file, void __user *arg,
"process %s did not enable P_Key index support.\n", "process %s did not enable P_Key index support.\n",
current->comm); current->comm);
dev_warn(&file->port->dev, dev_warn(&file->port->dev,
" Documentation/infiniband/user_mad.txt has info on the new ABI.\n"); " Documentation/infiniband/user_mad.rst has info on the new ABI.\n");
} }
} }
......
...@@ -6,7 +6,7 @@ config INFINIBAND_IPOIB ...@@ -6,7 +6,7 @@ config INFINIBAND_IPOIB
transports IP packets over InfiniBand so you can use your IB transports IP packets over InfiniBand so you can use your IB
device as a fancy NIC. device as a fancy NIC.
See Documentation/infiniband/ipoib.txt for more information See Documentation/infiniband/ipoib.rst for more information
config INFINIBAND_IPOIB_CM config INFINIBAND_IPOIB_CM
bool "IP-over-InfiniBand Connected Mode support" bool "IP-over-InfiniBand Connected Mode support"
......
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