1340 lines
59 KiB
C
1340 lines
59 KiB
C
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/*
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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/device.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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typedef struct scif_pinned_pages *scif_pinned_pages_t;
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/**
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* struct scif_range - SCIF registered range used in kernel mode
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* @cookie: cookie used internally by SCIF
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* @nr_pages: number of pages of PAGE_SIZE
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* @prot_flags: R/W protection
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* @phys_addr: Array of bus addresses
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* @va: Array of kernel virtual addresses backed by the pages in the phys_addr
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* array. The va is populated only when called on the host for a remote
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* SCIF connection on MIC. This is required to support the use case of DMA
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* between MIC and another device which is not a SCIF node e.g., an IB or
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* ethernet NIC.
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*/
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struct scif_range {
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void *cookie;
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int nr_pages;
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int prot_flags;
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dma_addr_t *phys_addr;
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void __iomem **va;
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};
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/**
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* struct scif_pollepd - SCIF endpoint to be monitored via scif_poll
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* @epd: SCIF endpoint
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* @events: requested events
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* @revents: returned events
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*/
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struct scif_pollepd {
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scif_epd_t epd;
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short events;
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short revents;
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};
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/**
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* scif_peer_dev - representation of a peer SCIF device
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*
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* Peer devices show up as PCIe devices for the mgmt node but not the cards.
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* The mgmt node discovers all the cards on the PCIe bus and informs the other
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* cards about their peers. Upon notification of a peer a node adds a peer
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* device to the peer bus to maintain symmetry in the way devices are
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* discovered across all nodes in the SCIF network.
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*
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* @dev: underlying device
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* @dnode - The destination node which this device will communicate with.
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*/
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struct scif_peer_dev {
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struct device dev;
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u8 dnode;
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};
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/**
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* scif_client - representation of a SCIF client
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* @name: client name
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* @probe - client method called when a peer device is registered
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* @remove - client method called when a peer device is unregistered
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* @si - subsys_interface used internally for implementing SCIF clients
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*/
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struct scif_client {
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const char *name;
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void (*probe)(struct scif_peer_dev *spdev);
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void (*remove)(struct scif_peer_dev *spdev);
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struct subsys_interface si;
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};
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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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/**
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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
|
||
|
|
* 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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*
|
||
|
|
* If epd is a connected endpoint, then its peer endpoint is also closed. RMAs
|
||
|
|
* which are in-process through epd or its peer endpoint will complete before
|
||
|
|
* scif_close() returns. Registered windows of the local and peer endpoints are
|
||
|
|
* released as if scif_unregister() was called against each window.
|
||
|
|
*
|
||
|
|
* Closing a SCIF endpoint does not affect local registered memory mapped by
|
||
|
|
* a SCIF endpoint on a remote node. The local memory remains mapped by the peer
|
||
|
|
* SCIF endpoint explicitly removed by calling munmap(..) by the peer.
|
||
|
|
*
|
||
|
|
* If the peer endpoint's receive queue is not empty at the time that epd is
|
||
|
|
* closed, then the peer endpoint can be passed as the endpoint parameter to
|
||
|
|
* scif_recv() until the receive queue is empty.
|
||
|
|
*
|
||
|
|
* epd is freed and may no longer be accessed.
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_close() 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
|
||
|
|
*/
|
||
|
|
int scif_close(scif_epd_t epd);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_send() - Send a message
|
||
|
|
* @epd: endpoint descriptor
|
||
|
|
* @msg: message buffer address
|
||
|
|
* @len: message length
|
||
|
|
* @flags: blocking mode flags
|
||
|
|
*
|
||
|
|
* scif_send() sends data to the peer of endpoint epd. Up to len bytes of data
|
||
|
|
* are copied from memory starting at address msg. On successful execution the
|
||
|
|
* return value of scif_send() is the number of bytes that were sent, and is
|
||
|
|
* zero if no bytes were sent because len was zero. scif_send() may be called
|
||
|
|
* only when the endpoint is in a connected state.
|
||
|
|
*
|
||
|
|
* If a scif_send() call is non-blocking, then it sends only those bytes which
|
||
|
|
* can be sent without waiting, up to a maximum of len bytes.
|
||
|
|
*
|
||
|
|
* If a scif_send() call is blocking, then it normally returns after sending
|
||
|
|
* all len bytes. If a blocking call is interrupted or the connection is
|
||
|
|
* reset, the call is considered successful if some bytes were sent or len is
|
||
|
|
* zero, otherwise the call is considered unsuccessful.
|
||
|
|
*
|
||
|
|
* In user mode, the select() and poll() functions can be used to determine
|
||
|
|
* when the send queue is not full. In kernel mode, the scif_poll() function
|
||
|
|
* may be used for this purpose.
|
||
|
|
*
|
||
|
|
* It is recommended that scif_send()/scif_recv() only be used for short
|
||
|
|
* control-type message communication between SCIF endpoints. The SCIF RMA
|
||
|
|
* APIs are expected to provide better performance for transfer sizes of
|
||
|
|
* 1024 bytes or longer for the current MIC hardware and software
|
||
|
|
* implementation.
|
||
|
|
*
|
||
|
|
* scif_send() will block until the entire message is sent if SCIF_SEND_BLOCK
|
||
|
|
* is passed as the flags argument.
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_send() returns the number of bytes sent;
|
||
|
|
* 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 len 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
|
||
|
|
*/
|
||
|
|
int scif_send(scif_epd_t epd, void *msg, int len, int flags);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_recv() - Receive a message
|
||
|
|
* @epd: endpoint descriptor
|
||
|
|
* @msg: message buffer address
|
||
|
|
* @len: message buffer length
|
||
|
|
* @flags: blocking mode flags
|
||
|
|
*
|
||
|
|
* scif_recv() receives data from the peer of endpoint epd. Up to len bytes of
|
||
|
|
* data are copied to memory starting at address msg. On successful execution
|
||
|
|
* the return value of scif_recv() is the number of bytes that were received,
|
||
|
|
* and is zero if no bytes were received because len was zero. scif_recv() may
|
||
|
|
* be called only when the endpoint is in a connected state.
|
||
|
|
*
|
||
|
|
* If a scif_recv() call is non-blocking, then it receives only those bytes
|
||
|
|
* which can be received without waiting, up to a maximum of len bytes.
|
||
|
|
*
|
||
|
|
* If a scif_recv() call is blocking, then it normally returns after receiving
|
||
|
|
* all len bytes. If the blocking call was interrupted due to a disconnection,
|
||
|
|
* subsequent calls to scif_recv() will copy all bytes received upto the point
|
||
|
|
* of disconnection.
|
||
|
|
*
|
||
|
|
* In user mode, the select() and poll() functions can be used to determine
|
||
|
|
* when data is available to be received. In kernel mode, the scif_poll()
|
||
|
|
* function may be used for this purpose.
|
||
|
|
*
|
||
|
|
* It is recommended that scif_send()/scif_recv() only be used for short
|
||
|
|
* control-type message communication between SCIF endpoints. The SCIF RMA
|
||
|
|
* APIs are expected to provide better performance for transfer sizes of
|
||
|
|
* 1024 bytes or longer for the current MIC hardware and software
|
||
|
|
* implementation.
|
||
|
|
*
|
||
|
|
* scif_recv() will block until the entire message is received if
|
||
|
|
* SCIF_RECV_BLOCK is passed as the flags argument.
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_recv() returns the number of bytes
|
||
|
|
* received; 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:
|
||
|
|
* EAGAIN - The destination node is returning from a low power state
|
||
|
|
* EBADF, ENOTTY - epd is not a valid endpoint descriptor
|
||
|
|
* ECONNRESET - Connection reset by peer
|
||
|
|
* EINVAL - flags is invalid, or len 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
|
||
|
|
*/
|
||
|
|
int scif_recv(scif_epd_t epd, void *msg, int len, int flags);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_register() - Mark a memory region for remote access.
|
||
|
|
* @epd: endpoint descriptor
|
||
|
|
* @addr: starting virtual address
|
||
|
|
* @len: length of range
|
||
|
|
* @offset: offset of window
|
||
|
|
* @prot_flags: read/write protection flags
|
||
|
|
* @map_flags: mapping flags
|
||
|
|
*
|
||
|
|
* The scif_register() function opens a window, a range of whole pages of the
|
||
|
|
* registered address space of the endpoint epd, starting at offset po and
|
||
|
|
* continuing for len bytes. The value of po, further described below, is a
|
||
|
|
* function of the parameters offset and len, and the value of map_flags. Each
|
||
|
|
* page of the window represents the physical memory page which backs the
|
||
|
|
* corresponding page of the range of virtual address pages starting at addr
|
||
|
|
* and continuing for len bytes. addr and len are constrained to be multiples
|
||
|
|
* of the page size. A successful scif_register() call returns po.
|
||
|
|
*
|
||
|
|
* When SCIF_MAP_FIXED is set in the map_flags argument, po will be offset
|
||
|
|
* exactly, and offset is constrained to be a multiple of the page size. The
|
||
|
|
* mapping established by scif_register() will not replace any existing
|
||
|
|
* registration; an error is returned if any page within the range [offset,
|
||
|
|
* offset + len - 1] intersects an existing window.
|
||
|
|
*
|
||
|
|
* When SCIF_MAP_FIXED is not set, the implementation uses offset in an
|
||
|
|
* implementation-defined manner to arrive at po. The po value so chosen will
|
||
|
|
* be an area of the registered address space that the implementation deems
|
||
|
|
* suitable for a mapping of len bytes. An offset value of 0 is interpreted as
|
||
|
|
* granting the implementation complete freedom in selecting po, subject to
|
||
|
|
* constraints described below. A non-zero value of offset is taken to be a
|
||
|
|
* suggestion of an offset near which the mapping should be placed. When the
|
||
|
|
* implementation selects a value for po, it does not replace any extant
|
||
|
|
* window. In all cases, po will be a multiple of the page size.
|
||
|
|
*
|
||
|
|
* The physical pages which are so represented by a window are available for
|
||
|
|
* access in calls to mmap(), scif_readfrom(), scif_writeto(),
|
||
|
|
* scif_vreadfrom(), and scif_vwriteto(). While a window is registered, the
|
||
|
|
* physical pages represented by the window will not be reused by the memory
|
||
|
|
* subsystem for any other purpose. Note that the same physical page may be
|
||
|
|
* represented by multiple windows.
|
||
|
|
*
|
||
|
|
* Subsequent operations which change the memory pages to which virtual
|
||
|
|
* addresses are mapped (such as mmap(), munmap()) have no effect on
|
||
|
|
* existing window.
|
||
|
|
*
|
||
|
|
* 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
|
||
|
|
*
|
||
|
|
* 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
|
||
|
|
* 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
|
||
|
|
* 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
|
||
|
|
* 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.
|
||
|
|
*/
|
||
|
|
int scif_get_node_ids(u16 *nodes, int len, u16 *self);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_pin_pages() - Pin a set of pages
|
||
|
|
* @addr: Virtual address of range to pin
|
||
|
|
* @len: Length of range to pin
|
||
|
|
* @prot_flags: Page protection flags
|
||
|
|
* @map_flags: Page classification flags
|
||
|
|
* @pinned_pages: Handle to pinned pages
|
||
|
|
*
|
||
|
|
* scif_pin_pages() pins (locks in physical memory) the physical pages which
|
||
|
|
* back the range of virtual address pages starting at addr and continuing for
|
||
|
|
* len bytes. addr and len are constrained to be multiples of the page size. A
|
||
|
|
* successful scif_pin_pages() call returns a handle to pinned_pages which may
|
||
|
|
* be used in subsequent calls to scif_register_pinned_pages().
|
||
|
|
*
|
||
|
|
* The pages will remain pinned as long as there is a reference against the
|
||
|
|
* scif_pinned_pages_t value returned by scif_pin_pages() and until
|
||
|
|
* scif_unpin_pages() is called, passing the scif_pinned_pages_t value. A
|
||
|
|
* reference is added to a scif_pinned_pages_t value each time a window is
|
||
|
|
* created by calling scif_register_pinned_pages() and passing the
|
||
|
|
* scif_pinned_pages_t value. A reference is removed from a
|
||
|
|
* scif_pinned_pages_t value each time such a window is deleted.
|
||
|
|
*
|
||
|
|
* Subsequent operations which change the memory pages to which virtual
|
||
|
|
* addresses are mapped (such as mmap(), munmap()) have no effect on the
|
||
|
|
* scif_pinned_pages_t value or windows created against it.
|
||
|
|
*
|
||
|
|
* 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 against the pages
|
||
|
|
* SCIF_PROT_WRITE - allow write operations against the pages
|
||
|
|
* The map_flags argument can be set as SCIF_MAP_KERNEL to interpret addr as a
|
||
|
|
* kernel space address. By default, addr is interpreted as a user space
|
||
|
|
* address.
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_pin_pages() returns 0; otherwise the
|
||
|
|
* negative of one of the following errors is returned.
|
||
|
|
*
|
||
|
|
* Errors:
|
||
|
|
* EINVAL - prot_flags is invalid, map_flags is invalid, or offset is negative
|
||
|
|
* ENOMEM - Not enough space
|
||
|
|
*/
|
||
|
|
int scif_pin_pages(void *addr, size_t len, int prot_flags, int map_flags,
|
||
|
|
scif_pinned_pages_t *pinned_pages);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_unpin_pages() - Unpin a set of pages
|
||
|
|
* @pinned_pages: Handle to pinned pages to be unpinned
|
||
|
|
*
|
||
|
|
* scif_unpin_pages() prevents scif_register_pinned_pages() from registering new
|
||
|
|
* windows against pinned_pages. The physical pages represented by pinned_pages
|
||
|
|
* will remain pinned until all windows previously registered against
|
||
|
|
* pinned_pages are deleted (the window is scif_unregister()'d and all
|
||
|
|
* references to the window are removed (see scif_unregister()).
|
||
|
|
*
|
||
|
|
* pinned_pages must have been obtain from a previous call to scif_pin_pages().
|
||
|
|
* After calling scif_unpin_pages(), it is an error to pass pinned_pages to
|
||
|
|
* scif_register_pinned_pages().
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_unpin_pages() returns 0; otherwise the
|
||
|
|
* negative of one of the following errors is returned.
|
||
|
|
*
|
||
|
|
* Errors:
|
||
|
|
* EINVAL - pinned_pages is not valid
|
||
|
|
*/
|
||
|
|
int scif_unpin_pages(scif_pinned_pages_t pinned_pages);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_register_pinned_pages() - Mark a memory region for remote access.
|
||
|
|
* @epd: endpoint descriptor
|
||
|
|
* @pinned_pages: Handle to pinned pages
|
||
|
|
* @offset: Registered address space offset
|
||
|
|
* @map_flags: Flags which control where pages are mapped
|
||
|
|
*
|
||
|
|
* The scif_register_pinned_pages() function opens a window, a range of whole
|
||
|
|
* pages of the registered address space of the endpoint epd, starting at
|
||
|
|
* offset po. The value of po, further described below, is a function of the
|
||
|
|
* parameters offset and pinned_pages, and the value of map_flags. Each page of
|
||
|
|
* the window represents a corresponding physical memory page of the range
|
||
|
|
* represented by pinned_pages; the length of the window is the same as the
|
||
|
|
* length of range represented by pinned_pages. A successful
|
||
|
|
* scif_register_pinned_pages() call returns po as the return value.
|
||
|
|
*
|
||
|
|
* When SCIF_MAP_FIXED is set in the map_flags argument, po will be offset
|
||
|
|
* exactly, and offset is constrained to be a multiple of the page size. The
|
||
|
|
* mapping established by scif_register_pinned_pages() will not replace any
|
||
|
|
* existing registration; an error is returned if any page of the new window
|
||
|
|
* would intersect an existing window.
|
||
|
|
*
|
||
|
|
* When SCIF_MAP_FIXED is not set, the implementation uses offset in an
|
||
|
|
* implementation-defined manner to arrive at po. The po so chosen will be an
|
||
|
|
* area of the registered address space that the implementation deems suitable
|
||
|
|
* for a mapping of the required size. An offset value of 0 is interpreted as
|
||
|
|
* granting the implementation complete freedom in selecting po, subject to
|
||
|
|
* constraints described below. A non-zero value of offset is taken to be a
|
||
|
|
* suggestion of an offset near which the mapping should be placed. When the
|
||
|
|
* implementation selects a value for po, it does not replace any extant
|
||
|
|
* window. In all cases, po will be a multiple of the page size.
|
||
|
|
*
|
||
|
|
* The physical pages which are so represented by a window are available for
|
||
|
|
* access in calls to scif_get_pages(), scif_readfrom(), scif_writeto(),
|
||
|
|
* scif_vreadfrom(), and scif_vwriteto(). While a window is registered, the
|
||
|
|
* physical pages represented by the window will not be reused by the memory
|
||
|
|
* subsystem for any other purpose. Note that the same physical page may be
|
||
|
|
* represented by multiple windows.
|
||
|
|
*
|
||
|
|
* Windows created by scif_register_pinned_pages() are unregistered by
|
||
|
|
* scif_unregister().
|
||
|
|
*
|
||
|
|
* The map_flags argument can be set to SCIF_MAP_FIXED which interprets a
|
||
|
|
* fixed offset.
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_register_pinned_pages() returns the offset
|
||
|
|
* at which the mapping was placed (po); otherwise the negative of one of the
|
||
|
|
* following errors is returned.
|
||
|
|
*
|
||
|
|
* Errors:
|
||
|
|
* EADDRINUSE - SCIF_MAP_FIXED is set in map_flags and pages in the new window
|
||
|
|
* would intersect an existing window
|
||
|
|
* EAGAIN - The mapping could not be performed due to lack of resources
|
||
|
|
* ECONNRESET - Connection reset by peer
|
||
|
|
* EINVAL - map_flags is invalid, or SCIF_MAP_FIXED is set in map_flags, and
|
||
|
|
* offset is not a multiple of the page size, 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_pinned_pages(scif_epd_t epd,
|
||
|
|
scif_pinned_pages_t pinned_pages,
|
||
|
|
off_t offset, int map_flags);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_get_pages() - Add references to remote registered pages
|
||
|
|
* @epd: endpoint descriptor
|
||
|
|
* @offset: remote registered offset
|
||
|
|
* @len: length of range of pages
|
||
|
|
* @pages: returned scif_range structure
|
||
|
|
*
|
||
|
|
* scif_get_pages() returns the addresses of the physical pages represented by
|
||
|
|
* those pages of the registered address space of the peer of epd, starting at
|
||
|
|
* offset and continuing for len bytes. offset and len are constrained to be
|
||
|
|
* multiples of the page size.
|
||
|
|
*
|
||
|
|
* All of the pages in the specified range [offset, offset + len - 1] must be
|
||
|
|
* within a single window of the registered address space of the peer of epd.
|
||
|
|
*
|
||
|
|
* The addresses are returned as a virtually contiguous array pointed to by the
|
||
|
|
* phys_addr component of the scif_range structure whose address is returned in
|
||
|
|
* pages. The nr_pages component of scif_range is the length of the array. The
|
||
|
|
* prot_flags component of scif_range holds the protection flag value passed
|
||
|
|
* when the pages were registered.
|
||
|
|
*
|
||
|
|
* Each physical page whose address is returned by scif_get_pages() remains
|
||
|
|
* available and will not be released for reuse until the scif_range structure
|
||
|
|
* is returned in a call to scif_put_pages(). The scif_range structure returned
|
||
|
|
* by scif_get_pages() must be unmodified.
|
||
|
|
*
|
||
|
|
* It is an error to call scif_close() on an endpoint on which a scif_range
|
||
|
|
* structure of that endpoint has not been returned to scif_put_pages().
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_get_pages() returns 0; otherwise the
|
||
|
|
* negative of one of the following errors is returned.
|
||
|
|
* Errors:
|
||
|
|
* ECONNRESET - Connection reset by peer.
|
||
|
|
* EINVAL - offset is not a multiple of the page size, or offset is negative, or
|
||
|
|
* len is not a multiple of the page size
|
||
|
|
* 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 the peer epd
|
||
|
|
*/
|
||
|
|
int scif_get_pages(scif_epd_t epd, off_t offset, size_t len,
|
||
|
|
struct scif_range **pages);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_put_pages() - Remove references from remote registered pages
|
||
|
|
* @pages: pages to be returned
|
||
|
|
*
|
||
|
|
* scif_put_pages() releases a scif_range structure previously obtained by
|
||
|
|
* calling scif_get_pages(). The physical pages represented by pages may
|
||
|
|
* be reused when the window which represented those pages is unregistered.
|
||
|
|
* Therefore, those pages must not be accessed after calling scif_put_pages().
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_put_pages() returns 0; otherwise the
|
||
|
|
* negative of one of the following errors is returned.
|
||
|
|
* Errors:
|
||
|
|
* EINVAL - pages does not point to a valid scif_range structure, or
|
||
|
|
* the scif_range structure pointed to by pages was already returned
|
||
|
|
* 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
|
||
|
|
*/
|
||
|
|
int scif_put_pages(struct scif_range *pages);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* scif_poll() - Wait for some event on an endpoint
|
||
|
|
* @epds: Array of endpoint descriptors
|
||
|
|
* @nepds: Length of epds
|
||
|
|
* @timeout: Upper limit on time for which scif_poll() will block
|
||
|
|
*
|
||
|
|
* scif_poll() waits for one of a set of endpoints to become ready to perform
|
||
|
|
* an I/O operation.
|
||
|
|
*
|
||
|
|
* The epds argument specifies the endpoint descriptors to be examined and the
|
||
|
|
* events of interest for each endpoint descriptor. epds is a pointer to an
|
||
|
|
* array with one member for each open endpoint descriptor of interest.
|
||
|
|
*
|
||
|
|
* The number of items in the epds array is specified in nepds. The epd field
|
||
|
|
* of scif_pollepd is an endpoint descriptor of an open endpoint. The field
|
||
|
|
* events is a bitmask specifying the events which the application is
|
||
|
|
* interested in. The field revents is an output parameter, filled by the
|
||
|
|
* kernel with the events that actually occurred. The bits returned in revents
|
||
|
|
* can include any of those specified in events, or one of the values POLLERR,
|
||
|
|
* POLLHUP, or POLLNVAL. (These three bits are meaningless in the events
|
||
|
|
* field, and will be set in the revents field whenever the corresponding
|
||
|
|
* condition is true.)
|
||
|
|
*
|
||
|
|
* If none of the events requested (and no error) has occurred for any of the
|
||
|
|
* endpoint descriptors, then scif_poll() blocks until one of the events occurs.
|
||
|
|
*
|
||
|
|
* The timeout argument specifies an upper limit on the time for which
|
||
|
|
* scif_poll() will block, in milliseconds. Specifying a negative value in
|
||
|
|
* timeout means an infinite timeout.
|
||
|
|
*
|
||
|
|
* The following bits may be set in events and returned in revents.
|
||
|
|
* POLLIN - Data may be received without blocking. For a connected
|
||
|
|
* endpoint, this means that scif_recv() may be called without blocking. For a
|
||
|
|
* listening endpoint, this means that scif_accept() may be called without
|
||
|
|
* blocking.
|
||
|
|
* POLLOUT - Data may be sent without blocking. For a connected endpoint, this
|
||
|
|
* means that scif_send() may be called without blocking. POLLOUT may also be
|
||
|
|
* used to block waiting for a non-blocking connect to complete. This bit value
|
||
|
|
* has no meaning for a listening endpoint and is ignored if specified.
|
||
|
|
*
|
||
|
|
* The following bits are only returned in revents, and are ignored if set in
|
||
|
|
* events.
|
||
|
|
* POLLERR - An error occurred on the endpoint
|
||
|
|
* POLLHUP - The connection to the peer endpoint was disconnected
|
||
|
|
* POLLNVAL - The specified endpoint descriptor is invalid.
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* Upon successful completion, scif_poll() returns a non-negative value. A
|
||
|
|
* positive value indicates the total number of endpoint descriptors that have
|
||
|
|
* been selected (that is, endpoint descriptors for which the revents member is
|
||
|
|
* non-zero). A value of 0 indicates that the call timed out and no endpoint
|
||
|
|
* descriptors have been selected. 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:
|
||
|
|
* EINTR - A signal occurred before any requested event
|
||
|
|
* EINVAL - The nepds argument is greater than {OPEN_MAX}
|
||
|
|
* ENOMEM - There was no space to allocate file descriptor tables
|
||
|
|
*/
|
||
|
|
int scif_poll(struct scif_pollepd *epds, unsigned int nepds, long timeout);
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/**
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* scif_client_register() - Register a SCIF client
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* @client: client to be registered
|
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*
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* scif_client_register() registers a SCIF client. The probe() method
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* of the client is called when SCIF peer devices come online and the
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* remove() method is called when the peer devices disappear.
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||
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*
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||
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* Return:
|
||
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|
* Upon successful completion, scif_client_register() returns a non-negative
|
||
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|
* value. Otherwise the return value is the same as subsys_interface_register()
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* in the kernel.
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||
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|
*/
|
||
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int scif_client_register(struct scif_client *client);
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||
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/**
|
||
|
|
* scif_client_unregister() - Unregister a SCIF client
|
||
|
|
* @client: client to be unregistered
|
||
|
|
*
|
||
|
|
* scif_client_unregister() unregisters a SCIF client.
|
||
|
|
*
|
||
|
|
* Return:
|
||
|
|
* None
|
||
|
|
*/
|
||
|
|
void scif_client_unregister(struct scif_client *client);
|
||
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|
||
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|
#endif /* __SCIF_H__ */
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