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Diffstat (limited to 'include/linux/scif.h')
| -rw-r--r-- | include/linux/scif.h | 1339 |
1 files changed, 0 insertions, 1339 deletions
diff --git a/include/linux/scif.h b/include/linux/scif.h deleted file mode 100644 index eeb250b73c4b..000000000000 --- a/include/linux/scif.h +++ /dev/null @@ -1,1339 +0,0 @@ -/* - * Intel MIC Platform Software Stack (MPSS) - * - * This file is provided under a dual BSD/GPLv2 license. When using or - * redistributing this file, you may do so under either license. - * - * GPL LICENSE SUMMARY - * - * Copyright(c) 2014 Intel Corporation. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of version 2 of the GNU General Public License as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * BSD LICENSE - * - * Copyright(c) 2014 Intel Corporation. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * * Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * * Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in - * the documentation and/or other materials provided with the - * distribution. - * * Neither the name of Intel Corporation nor the names of its - * contributors may be used to endorse or promote products derived - * from this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - * - * Intel SCIF driver. - * - */ -#ifndef __SCIF_H__ -#define __SCIF_H__ - -#include <linux/types.h> -#include <linux/poll.h> -#include <linux/device.h> -#include <linux/scif_ioctl.h> - -#define SCIF_ACCEPT_SYNC 1 -#define SCIF_SEND_BLOCK 1 -#define SCIF_RECV_BLOCK 1 - -enum { - SCIF_PROT_READ = (1 << 0), - SCIF_PROT_WRITE = (1 << 1) -}; - -enum { - SCIF_MAP_FIXED = 0x10, - SCIF_MAP_KERNEL = 0x20, -}; - -enum { - SCIF_FENCE_INIT_SELF = (1 << 0), - SCIF_FENCE_INIT_PEER = (1 << 1), - SCIF_SIGNAL_LOCAL = (1 << 4), - SCIF_SIGNAL_REMOTE = (1 << 5) -}; - -enum { - SCIF_RMA_USECPU = (1 << 0), - SCIF_RMA_USECACHE = (1 << 1), - SCIF_RMA_SYNC = (1 << 2), - SCIF_RMA_ORDERED = (1 << 3) -}; - -/* End of SCIF Admin Reserved Ports */ -#define SCIF_ADMIN_PORT_END 1024 - -/* End of SCIF Reserved Ports */ -#define SCIF_PORT_RSVD 1088 - -typedef struct scif_endpt *scif_epd_t; -typedef struct scif_pinned_pages *scif_pinned_pages_t; - -/** - * struct scif_range - SCIF registered range used in kernel mode - * @cookie: cookie used internally by SCIF - * @nr_pages: number of pages of PAGE_SIZE - * @prot_flags: R/W protection - * @phys_addr: Array of bus addresses - * @va: Array of kernel virtual addresses backed by the pages in the phys_addr - * array. The va is populated only when called on the host for a remote - * SCIF connection on MIC. This is required to support the use case of DMA - * between MIC and another device which is not a SCIF node e.g., an IB or - * ethernet NIC. - */ -struct scif_range { - void *cookie; - int nr_pages; - int prot_flags; - dma_addr_t *phys_addr; - void __iomem **va; -}; - -/** - * struct scif_pollepd - SCIF endpoint to be monitored via scif_poll - * @epd: SCIF endpoint - * @events: requested events - * @revents: returned events - */ -struct scif_pollepd { - scif_epd_t epd; - __poll_t events; - __poll_t revents; -}; - -/** - * scif_peer_dev - representation of a peer SCIF device - * - * Peer devices show up as PCIe devices for the mgmt node but not the cards. - * The mgmt node discovers all the cards on the PCIe bus and informs the other - * cards about their peers. Upon notification of a peer a node adds a peer - * device to the peer bus to maintain symmetry in the way devices are - * discovered across all nodes in the SCIF network. - * - * @dev: underlying device - * @dnode - The destination node which this device will communicate with. - */ -struct scif_peer_dev { - struct device dev; - u8 dnode; -}; - -/** - * scif_client - representation of a SCIF client - * @name: client name - * @probe - client method called when a peer device is registered - * @remove - client method called when a peer device is unregistered - * @si - subsys_interface used internally for implementing SCIF clients - */ -struct scif_client { - const char *name; - void (*probe)(struct scif_peer_dev *spdev); - void (*remove)(struct scif_peer_dev *spdev); - struct subsys_interface si; -}; - -#define SCIF_OPEN_FAILED ((scif_epd_t)-1) -#define SCIF_REGISTER_FAILED ((off_t)-1) -#define SCIF_MMAP_FAILED ((void *)-1) - -/** - * scif_open() - Create an endpoint - * - * Return: - * Upon successful completion, scif_open() returns an endpoint descriptor to - * be used in subsequent SCIF functions calls to refer to that endpoint; - * otherwise in user mode SCIF_OPEN_FAILED (that is ((scif_epd_t)-1)) is - * returned and errno is set to indicate the error; in kernel mode a NULL - * scif_epd_t is returned. - * - * Errors: - * ENOMEM - Insufficient kernel memory was available - */ -scif_epd_t scif_open(void); - -/** - * scif_bind() - Bind an endpoint to a port - * @epd: endpoint descriptor - * @pn: port number - * - * scif_bind() binds endpoint epd to port pn, where pn is a port number on the - * local node. If pn is zero, a port number greater than or equal to - * SCIF_PORT_RSVD is assigned and returned. Each endpoint may be bound to - * exactly one local port. Ports less than 1024 when requested can only be bound - * by system (or root) processes or by processes executed by privileged users. - * - * Return: - * Upon successful completion, scif_bind() returns the port number to which epd - * is bound; 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 - * EINVAL - the endpoint or the port is already bound - * EISCONN - The endpoint is already connected - * ENOSPC - No port number available for assignment - * EACCES - The port requested is protected and the user is not the superuser - */ -int scif_bind(scif_epd_t epd, u16 pn); - -/** - * scif_listen() - Listen for connections on an endpoint - * @epd: endpoint descriptor - * @backlog: maximum pending connection requests - * - * scif_listen() marks the endpoint epd as a listening endpoint - that is, as - * an endpoint that will be used to accept incoming connection requests. Once - * so marked, the endpoint is said to be in the listening state and may not be - * used as the endpoint of a connection. - * - * The endpoint, epd, must have been bound to a port. - * - * The backlog argument defines the maximum length to which the queue of - * pending connections for epd may grow. If a connection request arrives when - * the queue is full, the client may receive an error with an indication that - * the connection was refused. - * - * Return: - * Upon successful completion, scif_listen() 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 - * EINVAL - the endpoint is not bound to a port - * EISCONN - The endpoint is already connected or listening - */ -int scif_listen(scif_epd_t epd, int backlog); - -/** - * scif_connect() - Initiate a connection on a port - * @epd: endpoint descriptor - * @dst: global id of port to which to connect - * - * The scif_connect() function requests the connection of endpoint epd to remote - * port dst. If the connection is successful, a peer endpoint, bound to dst, is - * created on node dst.node. On successful return, the connection is complete. - * - * If the endpoint epd has not already been bound to a port, scif_connect() - * will bind it to an unused local port. - * - * A connection is terminated when an endpoint of the connection is closed, - * either explicitly by scif_close(), or when a process that owns one of the - * endpoints of the connection is terminated. - * - * In user space, scif_connect() supports an asynchronous connection mode - * if the application has set the O_NONBLOCK flag on the endpoint via the - * fcntl() system call. Setting this flag will result in the calling process - * not to wait during scif_connect(). - * - * Return: - * Upon successful completion, scif_connect() returns the port ID to which the - * endpoint, epd, is bound; 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 - * ECONNREFUSED - The destination was not listening for connections or refused - * the connection request - * EINVAL - dst.port is not a valid port ID - * EISCONN - The endpoint is already connected - * ENOMEM - No buffer space is available - * ENODEV - The destination node does not exist, or the node is lost or existed, - * but is not currently in the network since it may have crashed - * ENOSPC - No port number available for assignment - * EOPNOTSUPP - The endpoint is listening and cannot be connected - */ -int scif_connect(scif_epd_t epd, struct scif_port_id *dst); - -/** - * scif_accept() - Accept a connection on an endpoint - * @epd: endpoint descriptor - * @peer: global id of port to which connected - * @newepd: new connected endpoint descriptor - * @flags: flags - * - * The scif_accept() call extracts the first connection request from the queue - * of pending connections for the port on which epd is listening. scif_accept() - * creates a new endpoint, bound to the same port as epd, and allocates a new - * SCIF endpoint descriptor, returned in newepd, for the endpoint. The new - * endpoint is connected to the endpoint through which the connection was - * requested. epd is unaffected by this call, and remains in the listening - * state. - * - * On successful return, peer holds the global port identifier (node id and - * local port number) of the port which requested the connection. - * - * A connection is terminated when an endpoint of the connection is closed, - * either explicitly by scif_close(), or when a process that owns one of the - * endpoints of the connection is terminated. - * - * The number of connections that can (subsequently) be accepted on epd is only - * limited by system resources (memory). - * - * The flags argument is formed by OR'ing together zero or more of the - * following values. - * SCIF_ACCEPT_SYNC - block until a connection request is presented. If - * SCIF_ACCEPT_SYNC is not in flags, and no pending - * connections are present on the queue, scif_accept() - * fails with an EAGAIN error - * - * In user mode, the select() and poll() functions can be used to determine - * when there is a connection request. In kernel mode, the scif_poll() - * function may be used for this purpose. A readable event will be delivered - * when a connection is requested. - * - * Return: - * Upon successful completion, scif_accept() 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: - * EAGAIN - SCIF_ACCEPT_SYNC is not set and no connections are present to be - * accepted or SCIF_ACCEPT_SYNC is not set and remote node failed to complete - * its connection request - * EBADF, ENOTTY - epd is not a valid endpoint descriptor - * EINTR - Interrupted function - * EINVAL - epd is not a listening endpoint, or flags is invalid, or peer is - * NULL, or newepd is NULL - * ENODEV - The requesting node is lost or existed, but is not currently in the - * network since it may have crashed - * ENOMEM - Not enough space - * ENOENT - Secondary part of epd registration failed - */ -int scif_accept(scif_epd_t epd, struct scif_port_id *peer, scif_epd_t - *newepd, int flags); - -/** - * scif_close() - Close an endpoint - * @epd: endpoint descriptor - * - * scif_close() closes an endpoint and performs necessary teardown of - * facilities associated with that endpoint. - * - * If epd is a listening endpoint then it will no longer accept connection - * requests on the port to which it is bound. Any pending connection requests - * are rejected. - * - * 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 EPOLLERR, - * EPOLLHUP, or EPOLLNVAL. (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. - * EPOLLIN - 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. - * EPOLLOUT - Data may be sent without blocking. For a connected endpoint, this - * means that scif_send() may be called without blocking. EPOLLOUT 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. - * EPOLLERR - An error occurred on the endpoint - * EPOLLHUP - The connection to the peer endpoint was disconnected - * EPOLLNVAL - 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); - -/** - * scif_client_register() - Register a SCIF client - * @client: client to be registered - * - * scif_client_register() registers a SCIF client. The probe() method - * of the client is called when SCIF peer devices come online and the - * remove() method is called when the peer devices disappear. - * - * Return: - * Upon successful completion, scif_client_register() returns a non-negative - * value. Otherwise the return value is the same as subsys_interface_register() - * in the kernel. - */ -int scif_client_register(struct scif_client *client); - -/** - * 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); - -#endif /* __SCIF_H__ */ |