994 lines
44 KiB
C
994 lines
44 KiB
C
/*
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* Intel MIC Platform Software Stack (MPSS)
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*
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* This file is provided under a dual BSD/GPLv2 license. When using or
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* redistributing this file, you may do so under either license.
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*
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* GPL LICENSE SUMMARY
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*
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* Copyright(c) 2014 Intel Corporation.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of version 2 of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* BSD LICENSE
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*
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* Copyright(c) 2014 Intel Corporation.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* * Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* * Neither the name of Intel Corporation nor the names of its
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* contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* Intel SCIF driver.
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*
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*/
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#ifndef __SCIF_H__
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#define __SCIF_H__
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#include <linux/types.h>
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#include <linux/poll.h>
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#include <linux/scif_ioctl.h>
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#define SCIF_ACCEPT_SYNC 1
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#define SCIF_SEND_BLOCK 1
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#define SCIF_RECV_BLOCK 1
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enum {
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SCIF_PROT_READ = (1 << 0),
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SCIF_PROT_WRITE = (1 << 1)
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};
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enum {
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SCIF_MAP_FIXED = 0x10,
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SCIF_MAP_KERNEL = 0x20,
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};
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enum {
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SCIF_FENCE_INIT_SELF = (1 << 0),
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SCIF_FENCE_INIT_PEER = (1 << 1),
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SCIF_SIGNAL_LOCAL = (1 << 4),
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SCIF_SIGNAL_REMOTE = (1 << 5)
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};
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enum {
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SCIF_RMA_USECPU = (1 << 0),
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SCIF_RMA_USECACHE = (1 << 1),
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SCIF_RMA_SYNC = (1 << 2),
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SCIF_RMA_ORDERED = (1 << 3)
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};
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/* End of SCIF Admin Reserved Ports */
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#define SCIF_ADMIN_PORT_END 1024
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/* End of SCIF Reserved Ports */
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#define SCIF_PORT_RSVD 1088
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typedef struct scif_endpt *scif_epd_t;
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#define SCIF_OPEN_FAILED ((scif_epd_t)-1)
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#define SCIF_REGISTER_FAILED ((off_t)-1)
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#define SCIF_MMAP_FAILED ((void *)-1)
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/**
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* scif_open() - Create an endpoint
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*
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* Return:
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* Upon successful completion, scif_open() returns an endpoint descriptor to
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* be used in subsequent SCIF functions calls to refer to that endpoint;
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* otherwise in user mode SCIF_OPEN_FAILED (that is ((scif_epd_t)-1)) is
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* returned and errno is set to indicate the error; in kernel mode a NULL
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* scif_epd_t is returned.
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*
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* Errors:
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* ENOMEM - Insufficient kernel memory was available
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*/
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scif_epd_t scif_open(void);
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/**
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* scif_bind() - Bind an endpoint to a port
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* @epd: endpoint descriptor
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* @pn: port number
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*
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* scif_bind() binds endpoint epd to port pn, where pn is a port number on the
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* local node. If pn is zero, a port number greater than or equal to
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* SCIF_PORT_RSVD is assigned and returned. Each endpoint may be bound to
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* exactly one local port. Ports less than 1024 when requested can only be bound
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* by system (or root) processes or by processes executed by privileged users.
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*
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* Return:
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* Upon successful completion, scif_bind() returns the port number to which epd
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* is bound; otherwise in user mode -1 is returned and errno is set to
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* indicate the error; in kernel mode the negative of one of the following
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* errors is returned.
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*
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* Errors:
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* EBADF, ENOTTY - epd is not a valid endpoint descriptor
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* EINVAL - the endpoint or the port is already bound
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* EISCONN - The endpoint is already connected
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* ENOSPC - No port number available for assignment
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* EACCES - The port requested is protected and the user is not the superuser
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*/
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int scif_bind(scif_epd_t epd, u16 pn);
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/**
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* scif_listen() - Listen for connections on an endpoint
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* @epd: endpoint descriptor
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* @backlog: maximum pending connection requests
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*
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* scif_listen() marks the endpoint epd as a listening endpoint - that is, as
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* an endpoint that will be used to accept incoming connection requests. Once
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* so marked, the endpoint is said to be in the listening state and may not be
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* used as the endpoint of a connection.
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*
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* The endpoint, epd, must have been bound to a port.
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*
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* The backlog argument defines the maximum length to which the queue of
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* pending connections for epd may grow. If a connection request arrives when
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* the queue is full, the client may receive an error with an indication that
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* the connection was refused.
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*
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* Return:
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* Upon successful completion, scif_listen() returns 0; otherwise in user mode
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* -1 is returned and errno is set to indicate the error; in kernel mode the
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* negative of one of the following errors is returned.
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*
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* Errors:
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* EBADF, ENOTTY - epd is not a valid endpoint descriptor
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* EINVAL - the endpoint is not bound to a port
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* EISCONN - The endpoint is already connected or listening
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*/
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int scif_listen(scif_epd_t epd, int backlog);
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/**
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* scif_connect() - Initiate a connection on a port
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* @epd: endpoint descriptor
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* @dst: global id of port to which to connect
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*
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* The scif_connect() function requests the connection of endpoint epd to remote
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* port dst. If the connection is successful, a peer endpoint, bound to dst, is
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* created on node dst.node. On successful return, the connection is complete.
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*
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* If the endpoint epd has not already been bound to a port, scif_connect()
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* will bind it to an unused local port.
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*
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* A connection is terminated when an endpoint of the connection is closed,
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* either explicitly by scif_close(), or when a process that owns one of the
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* endpoints of the connection is terminated.
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*
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* In user space, scif_connect() supports an asynchronous connection mode
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* if the application has set the O_NONBLOCK flag on the endpoint via the
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* fcntl() system call. Setting this flag will result in the calling process
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* not to wait during scif_connect().
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*
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* Return:
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* Upon successful completion, scif_connect() returns the port ID to which the
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* endpoint, epd, is bound; otherwise in user mode -1 is returned and errno is
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* set to indicate the error; in kernel mode the negative of one of the
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* following errors is returned.
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*
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* Errors:
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* EBADF, ENOTTY - epd is not a valid endpoint descriptor
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* ECONNREFUSED - The destination was not listening for connections or refused
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* the connection request
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* EINVAL - dst.port is not a valid port ID
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* EISCONN - The endpoint is already connected
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* ENOMEM - No buffer space is available
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* ENODEV - The destination node does not exist, or the node is lost or existed,
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* but is not currently in the network since it may have crashed
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* ENOSPC - No port number available for assignment
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* EOPNOTSUPP - The endpoint is listening and cannot be connected
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*/
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int scif_connect(scif_epd_t epd, struct scif_port_id *dst);
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/**
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* scif_accept() - Accept a connection on an endpoint
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* @epd: endpoint descriptor
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* @peer: global id of port to which connected
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* @newepd: new connected endpoint descriptor
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* @flags: flags
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*
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* The scif_accept() call extracts the first connection request from the queue
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* of pending connections for the port on which epd is listening. scif_accept()
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* creates a new endpoint, bound to the same port as epd, and allocates a new
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* SCIF endpoint descriptor, returned in newepd, for the endpoint. The new
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* endpoint is connected to the endpoint through which the connection was
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* requested. epd is unaffected by this call, and remains in the listening
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* state.
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*
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* On successful return, peer holds the global port identifier (node id and
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* local port number) of the port which requested the connection.
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*
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* A connection is terminated when an endpoint of the connection is closed,
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* either explicitly by scif_close(), or when a process that owns one of the
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* endpoints of the connection is terminated.
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*
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* The number of connections that can (subsequently) be accepted on epd is only
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* limited by system resources (memory).
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*
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* The flags argument is formed by OR'ing together zero or more of the
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* following values.
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* SCIF_ACCEPT_SYNC - block until a connection request is presented. If
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* SCIF_ACCEPT_SYNC is not in flags, and no pending
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* connections are present on the queue, scif_accept()
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* fails with an EAGAIN error
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*
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* In user mode, the select() and poll() functions can be used to determine
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* when there is a connection request. In kernel mode, the scif_poll()
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* function may be used for this purpose. A readable event will be delivered
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* when a connection is requested.
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*
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* Return:
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* Upon successful completion, scif_accept() returns 0; otherwise in user mode
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* -1 is returned and errno is set to indicate the error; in kernel mode the
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* negative of one of the following errors is returned.
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*
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* Errors:
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* EAGAIN - SCIF_ACCEPT_SYNC is not set and no connections are present to be
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* accepted or SCIF_ACCEPT_SYNC is not set and remote node failed to complete
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* its connection request
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* EBADF, ENOTTY - epd is not a valid endpoint descriptor
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* EINTR - Interrupted function
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* EINVAL - epd is not a listening endpoint, or flags is invalid, or peer is
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* NULL, or newepd is NULL
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* ENODEV - The requesting node is lost or existed, but is not currently in the
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* network since it may have crashed
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* ENOMEM - Not enough space
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* ENOENT - Secondary part of epd registration failed
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*/
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int scif_accept(scif_epd_t epd, struct scif_port_id *peer, scif_epd_t
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*newepd, int flags);
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/**
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* scif_close() - Close an endpoint
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* @epd: endpoint descriptor
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*
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* scif_close() closes an endpoint and performs necessary teardown of
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* facilities associated with that endpoint.
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*
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* If epd is a listening endpoint then it will no longer accept connection
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* requests on the port to which it is bound. Any pending connection requests
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* are rejected.
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*
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* If epd is a connected endpoint, then its peer endpoint is also closed. RMAs
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* which are in-process through epd or its peer endpoint will complete before
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* scif_close() returns. Registered windows of the local and peer endpoints are
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* released as if scif_unregister() was called against each window.
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*
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* Closing a SCIF endpoint does not affect local registered memory mapped by
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* a SCIF endpoint on a remote node. The local memory remains mapped by the peer
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* SCIF endpoint explicitly removed by calling munmap(..) by the peer.
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*
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* If the peer endpoint's receive queue is not empty at the time that epd is
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* closed, then the peer endpoint can be passed as the endpoint parameter to
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* scif_recv() until the receive queue is empty.
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*
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* epd is freed and may no longer be accessed.
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*
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* Return:
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* Upon successful completion, scif_close() returns 0; otherwise in user mode
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* -1 is returned and errno is set to indicate the error; in kernel mode the
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* negative of one of the following errors is returned.
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*
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* Errors:
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* EBADF, ENOTTY - epd is not a valid endpoint descriptor
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*/
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int scif_close(scif_epd_t epd);
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/**
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* scif_send() - Send a message
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* @epd: endpoint descriptor
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* @msg: message buffer address
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* @len: message length
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* @flags: blocking mode flags
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*
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* scif_send() sends data to the peer of endpoint epd. Up to len bytes of data
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* are copied from memory starting at address msg. On successful execution the
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* return value of scif_send() is the number of bytes that were sent, and is
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* zero if no bytes were sent because len was zero. scif_send() may be called
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* only when the endpoint is in a connected state.
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*
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* If a scif_send() call is non-blocking, then it sends only those bytes which
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* can be sent without waiting, up to a maximum of len bytes.
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*
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* If a scif_send() call is blocking, then it normally returns after sending
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* all len bytes. If a blocking call is interrupted or the connection is
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* reset, the call is considered successful if some bytes were sent or len is
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* zero, otherwise the call is considered unsuccessful.
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*
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* In user mode, the select() and poll() functions can be used to determine
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* when the send queue is not full. In kernel mode, the scif_poll() function
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* may be used for this purpose.
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*
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* It is recommended that scif_send()/scif_recv() only be used for short
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* control-type message communication between SCIF endpoints. The SCIF RMA
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* APIs are expected to provide better performance for transfer sizes of
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* 1024 bytes or longer for the current MIC hardware and software
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* implementation.
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*
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* scif_send() will block until the entire message is sent if SCIF_SEND_BLOCK
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* is passed as the flags argument.
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*
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* Return:
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* Upon successful completion, scif_send() returns the number of bytes sent;
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* otherwise in user mode -1 is returned and errno is set to indicate the
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* error; in kernel mode the negative of one of the following errors is
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* returned.
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*
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* Errors:
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* EBADF, ENOTTY - epd is not a valid endpoint descriptor
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* ECONNRESET - Connection reset by peer
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* EFAULT - An invalid address was specified for a parameter
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* EINVAL - flags is invalid, or len is negative
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* ENODEV - The remote node is lost or existed, but is not currently in the
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* network since it may have crashed
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* ENOMEM - Not enough space
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* ENOTCONN - The endpoint is not connected
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*/
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int scif_send(scif_epd_t epd, void *msg, int len, int flags);
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/**
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* scif_recv() - Receive a message
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* @epd: endpoint descriptor
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* @msg: message buffer address
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* @len: message buffer length
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* @flags: blocking mode flags
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*
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* scif_recv() receives data from the peer of endpoint epd. Up to len bytes of
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* data are copied to memory starting at address msg. On successful execution
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* the return value of scif_recv() is the number of bytes that were received,
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* and is zero if no bytes were received because len was zero. scif_recv() may
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* be called only when the endpoint is in a connected state.
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*
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* If a scif_recv() call is non-blocking, then it receives only those bytes
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* which can be received without waiting, up to a maximum of len bytes.
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*
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* If a scif_recv() call is blocking, then it normally returns after receiving
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* all len bytes. If the blocking call was interrupted due to a disconnection,
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* subsequent calls to scif_recv() will copy all bytes received upto the point
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* of disconnection.
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*
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* In user mode, the select() and poll() functions can be used to determine
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* when data is available to be received. In kernel mode, the scif_poll()
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* function may be used for this purpose.
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*
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* It is recommended that scif_send()/scif_recv() only be used for short
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* control-type message communication between SCIF endpoints. The SCIF RMA
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* APIs are expected to provide better performance for transfer sizes of
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* 1024 bytes or longer for the current MIC hardware and software
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* implementation.
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*
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* scif_recv() will block until the entire message is received if
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* SCIF_RECV_BLOCK is passed as the flags argument.
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*
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* Return:
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* Upon successful completion, scif_recv() returns the number of bytes
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* received; otherwise in user mode -1 is returned and errno is set to
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* indicate the error; in kernel mode the negative of one of the following
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* errors is returned.
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*
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* Errors:
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* EAGAIN - The destination node is returning from a low power state
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* EBADF, ENOTTY - epd is not a valid endpoint descriptor
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* ECONNRESET - Connection reset by peer
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* EFAULT - An invalid address was specified for a parameter
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* EINVAL - flags is invalid, or len is negative
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* ENODEV - The remote node is lost or existed, but is not currently in the
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* network since it may have crashed
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* ENOMEM - Not enough space
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* ENOTCONN - The endpoint is not connected
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*/
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int scif_recv(scif_epd_t epd, void *msg, int len, int flags);
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/**
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* scif_register() - Mark a memory region for remote access.
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* @epd: endpoint descriptor
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* @addr: starting virtual address
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* @len: length of range
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* @offset: offset of window
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* @prot_flags: read/write protection flags
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* @map_flags: mapping flags
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*
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* The scif_register() function opens a window, a range of whole pages of the
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* registered address space of the endpoint epd, starting at offset po and
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* continuing for len bytes. The value of po, further described below, is a
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* function of the parameters offset and len, and the value of map_flags. Each
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* page of the window represents the physical memory page which backs the
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* corresponding page of the range of virtual address pages starting at addr
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* and continuing for len bytes. addr and len are constrained to be multiples
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* of the page size. A successful scif_register() call returns po.
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*
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* When SCIF_MAP_FIXED is set in the map_flags argument, po will be offset
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* exactly, and offset is constrained to be a multiple of the page size. The
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* mapping established by scif_register() will not replace any existing
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* registration; an error is returned if any page within the range [offset,
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* offset + len - 1] intersects an existing window.
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*
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* When SCIF_MAP_FIXED is not set, the implementation uses offset in an
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* implementation-defined manner to arrive at po. The po value so chosen will
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* be an area of the registered address space that the implementation deems
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* suitable for a mapping of len bytes. An offset value of 0 is interpreted as
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* granting the implementation complete freedom in selecting po, subject to
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* constraints described below. A non-zero value of offset is taken to be a
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* suggestion of an offset near which the mapping should be placed. When the
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* implementation selects a value for po, it does not replace any extant
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* window. In all cases, po will be a multiple of the page size.
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*
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* The physical pages which are so represented by a window are available for
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* access in calls to mmap(), scif_readfrom(), scif_writeto(),
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* scif_vreadfrom(), and scif_vwriteto(). While a window is registered, the
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* physical pages represented by the window will not be reused by the memory
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* subsystem for any other purpose. Note that the same physical page may be
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* represented by multiple windows.
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*
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* Subsequent operations which change the memory pages to which virtual
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* addresses are mapped (such as mmap(), munmap()) have no effect on
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* existing window.
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|
*
|
|
* If the process will fork(), it is recommended that the registered
|
|
* virtual address range be marked with MADV_DONTFORK. Doing so will prevent
|
|
* problems due to copy-on-write semantics.
|
|
*
|
|
* The prot_flags argument is formed by OR'ing together one or more of the
|
|
* following values.
|
|
* SCIF_PROT_READ - allow read operations from the window
|
|
* SCIF_PROT_WRITE - allow write operations to the window
|
|
*
|
|
* The map_flags argument can be set to SCIF_MAP_FIXED which interprets a
|
|
* fixed offset.
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_register() returns the offset at which the
|
|
* mapping was placed (po); otherwise in user mode SCIF_REGISTER_FAILED (that
|
|
* is (off_t *)-1) is returned and errno is set to indicate the error; in
|
|
* kernel mode the negative of one of the following errors is returned.
|
|
*
|
|
* Errors:
|
|
* EADDRINUSE - SCIF_MAP_FIXED is set in map_flags, and pages in the range
|
|
* [offset, offset + len -1] are already registered
|
|
* EAGAIN - The mapping could not be performed due to lack of resources
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* EFAULT - Addresses in the range [addr, addr + len - 1] are invalid
|
|
* EINVAL - map_flags is invalid, or prot_flags is invalid, or SCIF_MAP_FIXED is
|
|
* set in flags, and offset is not a multiple of the page size, or addr is not a
|
|
* multiple of the page size, or len is not a multiple of the page size, or is
|
|
* 0, or offset is negative
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOMEM - Not enough space
|
|
* ENOTCONN -The endpoint is not connected
|
|
*/
|
|
off_t scif_register(scif_epd_t epd, void *addr, size_t len, off_t offset,
|
|
int prot_flags, int map_flags);
|
|
|
|
/**
|
|
* scif_unregister() - Mark a memory region for remote access.
|
|
* @epd: endpoint descriptor
|
|
* @offset: start of range to unregister
|
|
* @len: length of range to unregister
|
|
*
|
|
* The scif_unregister() function closes those previously registered windows
|
|
* which are entirely within the range [offset, offset + len - 1]. It is an
|
|
* error to specify a range which intersects only a subrange of a window.
|
|
*
|
|
* On a successful return, pages within the window may no longer be specified
|
|
* in calls to mmap(), scif_readfrom(), scif_writeto(), scif_vreadfrom(),
|
|
* scif_vwriteto(), scif_get_pages, and scif_fence_signal(). The window,
|
|
* however, continues to exist until all previous references against it are
|
|
* removed. A window is referenced if there is a mapping to it created by
|
|
* mmap(), or if scif_get_pages() was called against the window
|
|
* (and the pages have not been returned via scif_put_pages()). A window is
|
|
* also referenced while an RMA, in which some range of the window is a source
|
|
* or destination, is in progress. Finally a window is referenced while some
|
|
* offset in that window was specified to scif_fence_signal(), and the RMAs
|
|
* marked by that call to scif_fence_signal() have not completed. While a
|
|
* window is in this state, its registered address space pages are not
|
|
* available for use in a new registered window.
|
|
*
|
|
* When all such references to the window have been removed, its references to
|
|
* all the physical pages which it represents are removed. Similarly, the
|
|
* registered address space pages of the window become available for
|
|
* registration in a new window.
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_unregister() returns 0; otherwise in user
|
|
* mode -1 is returned and errno is set to indicate the error; in kernel mode
|
|
* the negative of one of the following errors is returned. In the event of an
|
|
* error, no windows are unregistered.
|
|
*
|
|
* Errors:
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* EINVAL - the range [offset, offset + len - 1] intersects a subrange of a
|
|
* window, or offset is negative
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOTCONN - The endpoint is not connected
|
|
* ENXIO - Offsets in the range [offset, offset + len - 1] are invalid for the
|
|
* registered address space of epd
|
|
*/
|
|
int scif_unregister(scif_epd_t epd, off_t offset, size_t len);
|
|
|
|
/**
|
|
* scif_readfrom() - Copy from a remote address space
|
|
* @epd: endpoint descriptor
|
|
* @loffset: offset in local registered address space to
|
|
* which to copy
|
|
* @len: length of range to copy
|
|
* @roffset: offset in remote registered address space
|
|
* from which to copy
|
|
* @rma_flags: transfer mode flags
|
|
*
|
|
* scif_readfrom() copies len bytes from the remote registered address space of
|
|
* the peer of endpoint epd, starting at the offset roffset to the local
|
|
* registered address space of epd, starting at the offset loffset.
|
|
*
|
|
* Each of the specified ranges [loffset, loffset + len - 1] and [roffset,
|
|
* roffset + len - 1] must be within some registered window or windows of the
|
|
* local and remote nodes. A range may intersect multiple registered windows,
|
|
* but only if those windows are contiguous in the registered address space.
|
|
*
|
|
* If rma_flags includes SCIF_RMA_USECPU, then the data is copied using
|
|
* programmed read/writes. Otherwise the data is copied using DMA. If rma_-
|
|
* flags includes SCIF_RMA_SYNC, then scif_readfrom() will return after the
|
|
* transfer is complete. Otherwise, the transfer may be performed asynchron-
|
|
* ously. The order in which any two asynchronous RMA operations complete
|
|
* is non-deterministic. The synchronization functions, scif_fence_mark()/
|
|
* scif_fence_wait() and scif_fence_signal(), can be used to synchronize to
|
|
* the completion of asynchronous RMA operations on the same endpoint.
|
|
*
|
|
* The DMA transfer of individual bytes is not guaranteed to complete in
|
|
* address order. If rma_flags includes SCIF_RMA_ORDERED, then the last
|
|
* cacheline or partial cacheline of the source range will become visible on
|
|
* the destination node after all other transferred data in the source
|
|
* range has become visible on the destination node.
|
|
*
|
|
* The optimal DMA performance will likely be realized if both
|
|
* loffset and roffset are cacheline aligned (are a multiple of 64). Lower
|
|
* performance will likely be realized if loffset and roffset are not
|
|
* cacheline aligned but are separated by some multiple of 64. The lowest level
|
|
* of performance is likely if loffset and roffset are not separated by a
|
|
* multiple of 64.
|
|
*
|
|
* The rma_flags argument is formed by ORing together zero or more of the
|
|
* following values.
|
|
* SCIF_RMA_USECPU - perform the transfer using the CPU, otherwise use the DMA
|
|
* engine.
|
|
* SCIF_RMA_SYNC - perform the transfer synchronously, returning after the
|
|
* transfer has completed. Passing this flag results in the
|
|
* current implementation busy waiting and consuming CPU cycles
|
|
* while the DMA transfer is in progress for best performance by
|
|
* avoiding the interrupt latency.
|
|
* SCIF_RMA_ORDERED - ensure that the last cacheline or partial cacheline of
|
|
* the source range becomes visible on the destination node
|
|
* after all other transferred data in the source range has
|
|
* become visible on the destination
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_readfrom() returns 0; otherwise in user
|
|
* mode -1 is returned and errno is set to indicate the error; in kernel mode
|
|
* the negative of one of the following errors is returned.
|
|
*
|
|
* Errors:
|
|
* EACCESS - Attempt to write to a read-only range
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* EINVAL - rma_flags is invalid
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOTCONN - The endpoint is not connected
|
|
* ENXIO - The range [loffset, loffset + len - 1] is invalid for the registered
|
|
* address space of epd, or, The range [roffset, roffset + len - 1] is invalid
|
|
* for the registered address space of the peer of epd, or loffset or roffset
|
|
* is negative
|
|
*/
|
|
int scif_readfrom(scif_epd_t epd, off_t loffset, size_t len, off_t
|
|
roffset, int rma_flags);
|
|
|
|
/**
|
|
* scif_writeto() - Copy to a remote address space
|
|
* @epd: endpoint descriptor
|
|
* @loffset: offset in local registered address space
|
|
* from which to copy
|
|
* @len: length of range to copy
|
|
* @roffset: offset in remote registered address space to
|
|
* which to copy
|
|
* @rma_flags: transfer mode flags
|
|
*
|
|
* scif_writeto() copies len bytes from the local registered address space of
|
|
* epd, starting at the offset loffset to the remote registered address space
|
|
* of the peer of endpoint epd, starting at the offset roffset.
|
|
*
|
|
* Each of the specified ranges [loffset, loffset + len - 1] and [roffset,
|
|
* roffset + len - 1] must be within some registered window or windows of the
|
|
* local and remote nodes. A range may intersect multiple registered windows,
|
|
* but only if those windows are contiguous in the registered address space.
|
|
*
|
|
* If rma_flags includes SCIF_RMA_USECPU, then the data is copied using
|
|
* programmed read/writes. Otherwise the data is copied using DMA. If rma_-
|
|
* flags includes SCIF_RMA_SYNC, then scif_writeto() will return after the
|
|
* transfer is complete. Otherwise, the transfer may be performed asynchron-
|
|
* ously. The order in which any two asynchronous RMA operations complete
|
|
* is non-deterministic. The synchronization functions, scif_fence_mark()/
|
|
* scif_fence_wait() and scif_fence_signal(), can be used to synchronize to
|
|
* the completion of asynchronous RMA operations on the same endpoint.
|
|
*
|
|
* The DMA transfer of individual bytes is not guaranteed to complete in
|
|
* address order. If rma_flags includes SCIF_RMA_ORDERED, then the last
|
|
* cacheline or partial cacheline of the source range will become visible on
|
|
* the destination node after all other transferred data in the source
|
|
* range has become visible on the destination node.
|
|
*
|
|
* The optimal DMA performance will likely be realized if both
|
|
* loffset and roffset are cacheline aligned (are a multiple of 64). Lower
|
|
* performance will likely be realized if loffset and roffset are not cacheline
|
|
* aligned but are separated by some multiple of 64. The lowest level of
|
|
* performance is likely if loffset and roffset are not separated by a multiple
|
|
* of 64.
|
|
*
|
|
* The rma_flags argument is formed by ORing together zero or more of the
|
|
* following values.
|
|
* SCIF_RMA_USECPU - perform the transfer using the CPU, otherwise use the DMA
|
|
* engine.
|
|
* SCIF_RMA_SYNC - perform the transfer synchronously, returning after the
|
|
* transfer has completed. Passing this flag results in the
|
|
* current implementation busy waiting and consuming CPU cycles
|
|
* while the DMA transfer is in progress for best performance by
|
|
* avoiding the interrupt latency.
|
|
* SCIF_RMA_ORDERED - ensure that the last cacheline or partial cacheline of
|
|
* the source range becomes visible on the destination node
|
|
* after all other transferred data in the source range has
|
|
* become visible on the destination
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_readfrom() returns 0; otherwise in user
|
|
* mode -1 is returned and errno is set to indicate the error; in kernel mode
|
|
* the negative of one of the following errors is returned.
|
|
*
|
|
* Errors:
|
|
* EACCESS - Attempt to write to a read-only range
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* EINVAL - rma_flags is invalid
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOTCONN - The endpoint is not connected
|
|
* ENXIO - The range [loffset, loffset + len - 1] is invalid for the registered
|
|
* address space of epd, or, The range [roffset , roffset + len -1] is invalid
|
|
* for the registered address space of the peer of epd, or loffset or roffset
|
|
* is negative
|
|
*/
|
|
int scif_writeto(scif_epd_t epd, off_t loffset, size_t len, off_t
|
|
roffset, int rma_flags);
|
|
|
|
/**
|
|
* scif_vreadfrom() - Copy from a remote address space
|
|
* @epd: endpoint descriptor
|
|
* @addr: address to which to copy
|
|
* @len: length of range to copy
|
|
* @roffset: offset in remote registered address space
|
|
* from which to copy
|
|
* @rma_flags: transfer mode flags
|
|
*
|
|
* scif_vreadfrom() copies len bytes from the remote registered address
|
|
* space of the peer of endpoint epd, starting at the offset roffset, to local
|
|
* memory, starting at addr.
|
|
*
|
|
* The specified range [roffset, roffset + len - 1] must be within some
|
|
* registered window or windows of the remote nodes. The range may
|
|
* intersect multiple registered windows, but only if those windows are
|
|
* contiguous in the registered address space.
|
|
*
|
|
* If rma_flags includes SCIF_RMA_USECPU, then the data is copied using
|
|
* programmed read/writes. Otherwise the data is copied using DMA. If rma_-
|
|
* flags includes SCIF_RMA_SYNC, then scif_vreadfrom() will return after the
|
|
* transfer is complete. Otherwise, the transfer may be performed asynchron-
|
|
* ously. The order in which any two asynchronous RMA operations complete
|
|
* is non-deterministic. The synchronization functions, scif_fence_mark()/
|
|
* scif_fence_wait() and scif_fence_signal(), can be used to synchronize to
|
|
* the completion of asynchronous RMA operations on the same endpoint.
|
|
*
|
|
* The DMA transfer of individual bytes is not guaranteed to complete in
|
|
* address order. If rma_flags includes SCIF_RMA_ORDERED, then the last
|
|
* cacheline or partial cacheline of the source range will become visible on
|
|
* the destination node after all other transferred data in the source
|
|
* range has become visible on the destination node.
|
|
*
|
|
* If rma_flags includes SCIF_RMA_USECACHE, then the physical pages which back
|
|
* the specified local memory range may be remain in a pinned state even after
|
|
* the specified transfer completes. This may reduce overhead if some or all of
|
|
* the same virtual address range is referenced in a subsequent call of
|
|
* scif_vreadfrom() or scif_vwriteto().
|
|
*
|
|
* The optimal DMA performance will likely be realized if both
|
|
* addr and roffset are cacheline aligned (are a multiple of 64). Lower
|
|
* performance will likely be realized if addr and roffset are not
|
|
* cacheline aligned but are separated by some multiple of 64. The lowest level
|
|
* of performance is likely if addr and roffset are not separated by a
|
|
* multiple of 64.
|
|
*
|
|
* The rma_flags argument is formed by ORing together zero or more of the
|
|
* following values.
|
|
* SCIF_RMA_USECPU - perform the transfer using the CPU, otherwise use the DMA
|
|
* engine.
|
|
* SCIF_RMA_USECACHE - enable registration caching
|
|
* SCIF_RMA_SYNC - perform the transfer synchronously, returning after the
|
|
* transfer has completed. Passing this flag results in the
|
|
* current implementation busy waiting and consuming CPU cycles
|
|
* while the DMA transfer is in progress for best performance by
|
|
* avoiding the interrupt latency.
|
|
* SCIF_RMA_ORDERED - ensure that the last cacheline or partial cacheline of
|
|
* the source range becomes visible on the destination node
|
|
* after all other transferred data in the source range has
|
|
* become visible on the destination
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_vreadfrom() returns 0; otherwise in user
|
|
* mode -1 is returned and errno is set to indicate the error; in kernel mode
|
|
* the negative of one of the following errors is returned.
|
|
*
|
|
* Errors:
|
|
* EACCESS - Attempt to write to a read-only range
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* EFAULT - Addresses in the range [addr, addr + len - 1] are invalid
|
|
* EINVAL - rma_flags is invalid
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOTCONN - The endpoint is not connected
|
|
* ENXIO - Offsets in the range [roffset, roffset + len - 1] are invalid for the
|
|
* registered address space of epd
|
|
*/
|
|
int scif_vreadfrom(scif_epd_t epd, void *addr, size_t len, off_t roffset,
|
|
int rma_flags);
|
|
|
|
/**
|
|
* scif_vwriteto() - Copy to a remote address space
|
|
* @epd: endpoint descriptor
|
|
* @addr: address from which to copy
|
|
* @len: length of range to copy
|
|
* @roffset: offset in remote registered address space to
|
|
* which to copy
|
|
* @rma_flags: transfer mode flags
|
|
*
|
|
* scif_vwriteto() copies len bytes from the local memory, starting at addr, to
|
|
* the remote registered address space of the peer of endpoint epd, starting at
|
|
* the offset roffset.
|
|
*
|
|
* The specified range [roffset, roffset + len - 1] must be within some
|
|
* registered window or windows of the remote nodes. The range may intersect
|
|
* multiple registered windows, but only if those windows are contiguous in the
|
|
* registered address space.
|
|
*
|
|
* If rma_flags includes SCIF_RMA_USECPU, then the data is copied using
|
|
* programmed read/writes. Otherwise the data is copied using DMA. If rma_-
|
|
* flags includes SCIF_RMA_SYNC, then scif_vwriteto() will return after the
|
|
* transfer is complete. Otherwise, the transfer may be performed asynchron-
|
|
* ously. The order in which any two asynchronous RMA operations complete
|
|
* is non-deterministic. The synchronization functions, scif_fence_mark()/
|
|
* scif_fence_wait() and scif_fence_signal(), can be used to synchronize to
|
|
* the completion of asynchronous RMA operations on the same endpoint.
|
|
*
|
|
* The DMA transfer of individual bytes is not guaranteed to complete in
|
|
* address order. If rma_flags includes SCIF_RMA_ORDERED, then the last
|
|
* cacheline or partial cacheline of the source range will become visible on
|
|
* the destination node after all other transferred data in the source
|
|
* range has become visible on the destination node.
|
|
*
|
|
* If rma_flags includes SCIF_RMA_USECACHE, then the physical pages which back
|
|
* the specified local memory range may be remain in a pinned state even after
|
|
* the specified transfer completes. This may reduce overhead if some or all of
|
|
* the same virtual address range is referenced in a subsequent call of
|
|
* scif_vreadfrom() or scif_vwriteto().
|
|
*
|
|
* The optimal DMA performance will likely be realized if both
|
|
* addr and offset are cacheline aligned (are a multiple of 64). Lower
|
|
* performance will likely be realized if addr and offset are not cacheline
|
|
* aligned but are separated by some multiple of 64. The lowest level of
|
|
* performance is likely if addr and offset are not separated by a multiple of
|
|
* 64.
|
|
*
|
|
* The rma_flags argument is formed by ORing together zero or more of the
|
|
* following values.
|
|
* SCIF_RMA_USECPU - perform the transfer using the CPU, otherwise use the DMA
|
|
* engine.
|
|
* SCIF_RMA_USECACHE - allow registration caching
|
|
* SCIF_RMA_SYNC - perform the transfer synchronously, returning after the
|
|
* transfer has completed. Passing this flag results in the
|
|
* current implementation busy waiting and consuming CPU cycles
|
|
* while the DMA transfer is in progress for best performance by
|
|
* avoiding the interrupt latency.
|
|
* SCIF_RMA_ORDERED - ensure that the last cacheline or partial cacheline of
|
|
* the source range becomes visible on the destination node
|
|
* after all other transferred data in the source range has
|
|
* become visible on the destination
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_vwriteto() returns 0; otherwise in user
|
|
* mode -1 is returned and errno is set to indicate the error; in kernel mode
|
|
* the negative of one of the following errors is returned.
|
|
*
|
|
* Errors:
|
|
* EACCESS - Attempt to write to a read-only range
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* EFAULT - Addresses in the range [addr, addr + len - 1] are invalid
|
|
* EINVAL - rma_flags is invalid
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOTCONN - The endpoint is not connected
|
|
* ENXIO - Offsets in the range [roffset, roffset + len - 1] are invalid for the
|
|
* registered address space of epd
|
|
*/
|
|
int scif_vwriteto(scif_epd_t epd, void *addr, size_t len, off_t roffset,
|
|
int rma_flags);
|
|
|
|
/**
|
|
* scif_fence_mark() - Mark previously issued RMAs
|
|
* @epd: endpoint descriptor
|
|
* @flags: control flags
|
|
* @mark: marked value returned as output.
|
|
*
|
|
* scif_fence_mark() returns after marking the current set of all uncompleted
|
|
* RMAs initiated through the endpoint epd or the current set of all
|
|
* uncompleted RMAs initiated through the peer of endpoint epd. The RMAs are
|
|
* marked with a value returned at mark. The application may subsequently call
|
|
* scif_fence_wait(), passing the value returned at mark, to await completion
|
|
* of all RMAs so marked.
|
|
*
|
|
* The flags argument has exactly one of the following values.
|
|
* SCIF_FENCE_INIT_SELF - RMA operations initiated through endpoint
|
|
* epd are marked
|
|
* SCIF_FENCE_INIT_PEER - RMA operations initiated through the peer
|
|
* of endpoint epd are marked
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_fence_mark() returns 0; otherwise in user
|
|
* mode -1 is returned and errno is set to indicate the error; in kernel mode
|
|
* the negative of one of the following errors is returned.
|
|
*
|
|
* Errors:
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* EINVAL - flags is invalid
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOTCONN - The endpoint is not connected
|
|
* ENOMEM - Insufficient kernel memory was available
|
|
*/
|
|
int scif_fence_mark(scif_epd_t epd, int flags, int *mark);
|
|
|
|
/**
|
|
* scif_fence_wait() - Wait for completion of marked RMAs
|
|
* @epd: endpoint descriptor
|
|
* @mark: mark request
|
|
*
|
|
* scif_fence_wait() returns after all RMAs marked with mark have completed.
|
|
* The value passed in mark must have been obtained in a previous call to
|
|
* scif_fence_mark().
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_fence_wait() returns 0; otherwise in user
|
|
* mode -1 is returned and errno is set to indicate the error; in kernel mode
|
|
* the negative of one of the following errors is returned.
|
|
*
|
|
* Errors:
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOTCONN - The endpoint is not connected
|
|
* ENOMEM - Insufficient kernel memory was available
|
|
*/
|
|
int scif_fence_wait(scif_epd_t epd, int mark);
|
|
|
|
/**
|
|
* scif_fence_signal() - Request a memory update on completion of RMAs
|
|
* @epd: endpoint descriptor
|
|
* @loff: local offset
|
|
* @lval: local value to write to loffset
|
|
* @roff: remote offset
|
|
* @rval: remote value to write to roffset
|
|
* @flags: flags
|
|
*
|
|
* scif_fence_signal() returns after marking the current set of all uncompleted
|
|
* RMAs initiated through the endpoint epd or marking the current set of all
|
|
* uncompleted RMAs initiated through the peer of endpoint epd.
|
|
*
|
|
* If flags includes SCIF_SIGNAL_LOCAL, then on completion of the RMAs in the
|
|
* marked set, lval is written to memory at the address corresponding to offset
|
|
* loff in the local registered address space of epd. loff must be within a
|
|
* registered window. If flags includes SCIF_SIGNAL_REMOTE, then on completion
|
|
* of the RMAs in the marked set, rval is written to memory at the address
|
|
* corresponding to offset roff in the remote registered address space of epd.
|
|
* roff must be within a remote registered window of the peer of epd. Note
|
|
* that any specified offset must be DWORD (4 byte / 32 bit) aligned.
|
|
*
|
|
* The flags argument is formed by OR'ing together the following.
|
|
* Exactly one of the following values.
|
|
* SCIF_FENCE_INIT_SELF - RMA operations initiated through endpoint
|
|
* epd are marked
|
|
* SCIF_FENCE_INIT_PEER - RMA operations initiated through the peer
|
|
* of endpoint epd are marked
|
|
* One or more of the following values.
|
|
* SCIF_SIGNAL_LOCAL - On completion of the marked set of RMAs, write lval to
|
|
* memory at the address corresponding to offset loff in the local
|
|
* registered address space of epd.
|
|
* SCIF_SIGNAL_REMOTE - On completion of the marked set of RMAs, write rval to
|
|
* memory at the address corresponding to offset roff in the remote
|
|
* registered address space of epd.
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_fence_signal() returns 0; otherwise in
|
|
* user mode -1 is returned and errno is set to indicate the error; in kernel
|
|
* mode the negative of one of the following errors is returned.
|
|
*
|
|
* Errors:
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
|
* ECONNRESET - Connection reset by peer
|
|
* EINVAL - flags is invalid, or loff or roff are not DWORD aligned
|
|
* ENODEV - The remote node is lost or existed, but is not currently in the
|
|
* network since it may have crashed
|
|
* ENOTCONN - The endpoint is not connected
|
|
* ENXIO - loff is invalid for the registered address of epd, or roff is invalid
|
|
* for the registered address space, of the peer of epd
|
|
*/
|
|
int scif_fence_signal(scif_epd_t epd, off_t loff, u64 lval, off_t roff,
|
|
u64 rval, int flags);
|
|
|
|
/**
|
|
* scif_get_node_ids() - Return information about online nodes
|
|
* @nodes: array in which to return online node IDs
|
|
* @len: number of entries in the nodes array
|
|
* @self: address to place the node ID of the local node
|
|
*
|
|
* scif_get_node_ids() fills in the nodes array with up to len node IDs of the
|
|
* nodes in the SCIF network. If there is not enough space in nodes, as
|
|
* indicated by the len parameter, only len node IDs are returned in nodes. The
|
|
* return value of scif_get_node_ids() is the total number of nodes currently in
|
|
* the SCIF network. By checking the return value against the len parameter,
|
|
* the user may determine if enough space for nodes was allocated.
|
|
*
|
|
* The node ID of the local node is returned at self.
|
|
*
|
|
* Return:
|
|
* Upon successful completion, scif_get_node_ids() returns the actual number of
|
|
* online nodes in the SCIF network including 'self'; otherwise in user mode
|
|
* -1 is returned and errno is set to indicate the error; in kernel mode no
|
|
* errors are returned.
|
|
*
|
|
* Errors:
|
|
* EFAULT - Bad address
|
|
*/
|
|
int scif_get_node_ids(u16 *nodes, int len, u16 *self);
|
|
|
|
#endif /* __SCIF_H__ */
|