transport.c

linux 内核源代码

/*
 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the BSD-type
 * license below:
 *
 * 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 the Network Appliance, Inc. 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.
 */

/*
 * transport.c
 *
 * This file contains the top-level implementation of an RPC RDMA
 * transport.
 *
 * Naming convention: functions beginning with xprt_ are part of the
 * transport switch. All others are RPC RDMA internal.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/seq_file.h>

#include "xprt_rdma.h"

#ifdef RPC_DEBUG
# define RPCDBG_FACILITY	RPCDBG_TRANS
#endif

MODULE_LICENSE("Dual BSD/GPL");

MODULE_DESCRIPTION("RPC/RDMA Transport for Linux kernel NFS");
MODULE_AUTHOR("Network Appliance, Inc.");

/*
 * tunables
 */

static unsigned int xprt_rdma_slot_table_entries = RPCRDMA_DEF_SLOT_TABLE;
static unsigned int xprt_rdma_max_inline_read = RPCRDMA_DEF_INLINE;
static unsigned int xprt_rdma_max_inline_write = RPCRDMA_DEF_INLINE;
static unsigned int xprt_rdma_inline_write_padding;
#if !RPCRDMA_PERSISTENT_REGISTRATION
static unsigned int xprt_rdma_memreg_strategy = RPCRDMA_REGISTER; /* FMR? */
#else
static unsigned int xprt_rdma_memreg_strategy = RPCRDMA_ALLPHYSICAL;
#endif

#ifdef RPC_DEBUG

static unsigned int min_slot_table_size = RPCRDMA_MIN_SLOT_TABLE;
static unsigned int max_slot_table_size = RPCRDMA_MAX_SLOT_TABLE;
static unsigned int zero;
static unsigned int max_padding = PAGE_SIZE;
static unsigned int min_memreg = RPCRDMA_BOUNCEBUFFERS;
static unsigned int max_memreg = RPCRDMA_LAST - 1;

static struct ctl_table_header *sunrpc_table_header;

static ctl_table xr_tunables_table[] = {
	{
		.ctl_name       = CTL_UNNUMBERED,
		.procname	= "rdma_slot_table_entries",
		.data		= &xprt_rdma_slot_table_entries,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_slot_table_size,
		.extra2		= &max_slot_table_size
	},
	{
		.ctl_name       = CTL_UNNUMBERED,
		.procname	= "rdma_max_inline_read",
		.data		= &xprt_rdma_max_inline_read,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
		.strategy	= &sysctl_intvec,
	},
	{
		.ctl_name       = CTL_UNNUMBERED,
		.procname	= "rdma_max_inline_write",
		.data		= &xprt_rdma_max_inline_write,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
		.strategy	= &sysctl_intvec,
	},
	{
		.ctl_name       = CTL_UNNUMBERED,
		.procname	= "rdma_inline_write_padding",
		.data		= &xprt_rdma_inline_write_padding,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &max_padding,
	},
	{
		.ctl_name       = CTL_UNNUMBERED,
		.procname	= "rdma_memreg_strategy",
		.data		= &xprt_rdma_memreg_strategy,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_memreg,
		.extra2		= &max_memreg,
	},
	{
		.ctl_name = 0,
	},
};

static ctl_table sunrpc_table[] = {
	{
		.ctl_name	= CTL_SUNRPC,
		.procname	= "sunrpc",
		.mode		= 0555,
		.child		= xr_tunables_table
	},
	{
		.ctl_name = 0,
	},
};

#endif

static struct rpc_xprt_ops xprt_rdma_procs;	/* forward reference */

static void
xprt_rdma_format_addresses(struct rpc_xprt *xprt)
{
	struct sockaddr_in *addr = (struct sockaddr_in *)
					&rpcx_to_rdmad(xprt).addr;
	char *buf;

	buf = kzalloc(20, GFP_KERNEL);
	if (buf)
		snprintf(buf, 20, NIPQUAD_FMT, NIPQUAD(addr->sin_addr.s_addr));
	xprt->address_strings[RPC_DISPLAY_ADDR] = buf;

	buf = kzalloc(8, GFP_KERNEL);
	if (buf)
		snprintf(buf, 8, "%u", ntohs(addr->sin_port));
	xprt->address_strings[RPC_DISPLAY_PORT] = buf;

	xprt->address_strings[RPC_DISPLAY_PROTO] = "rdma";

	buf = kzalloc(48, GFP_KERNEL);
	if (buf)
		snprintf(buf, 48, "addr="NIPQUAD_FMT" port=%u proto=%s",
			NIPQUAD(addr->sin_addr.s_addr),
			ntohs(addr->sin_port), "rdma");
	xprt->address_strings[RPC_DISPLAY_ALL] = buf;

	buf = kzalloc(10, GFP_KERNEL);
	if (buf)
		snprintf(buf, 10, "%02x%02x%02x%02x",
			NIPQUAD(addr->sin_addr.s_addr));
	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = buf;

	buf = kzalloc(8, GFP_KERNEL);
	if (buf)
		snprintf(buf, 8, "%4hx", ntohs(addr->sin_port));
	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = buf;

	buf = kzalloc(30, GFP_KERNEL);
	if (buf)
		snprintf(buf, 30, NIPQUAD_FMT".%u.%u",
			NIPQUAD(addr->sin_addr.s_addr),
			ntohs(addr->sin_port) >> 8,
			ntohs(addr->sin_port) & 0xff);
	xprt->address_strings[RPC_DISPLAY_UNIVERSAL_ADDR] = buf;

	/* netid */
	xprt->address_strings[RPC_DISPLAY_NETID] = "rdma";
}

static void
xprt_rdma_free_addresses(struct rpc_xprt *xprt)
{
	kfree(xprt->address_strings[RPC_DISPLAY_ADDR]);
	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
	kfree(xprt->address_strings[RPC_DISPLAY_ALL]);
	kfree(xprt->address_strings[RPC_DISPLAY_HEX_ADDR]);
	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
	kfree(xprt->address_strings[RPC_DISPLAY_UNIVERSAL_ADDR]);
}

static void
xprt_rdma_connect_worker(struct work_struct *work)
{
	struct rpcrdma_xprt *r_xprt =
		container_of(work, struct rpcrdma_xprt, rdma_connect.work);
	struct rpc_xprt *xprt = &r_xprt->xprt;
	int rc = 0;

	if (!xprt->shutdown) {
		xprt_clear_connected(xprt);

		dprintk("RPC:       %s: %sconnect\n", __func__,
				r_xprt->rx_ep.rep_connected != 0 ? "re" : "");
		rc = rpcrdma_ep_connect(&r_xprt->rx_ep, &r_xprt->rx_ia);
		if (rc)
			goto out;
	}
	goto out_clear;

out:
	xprt_wake_pending_tasks(xprt, rc);

out_clear:
	dprintk("RPC:       %s: exit\n", __func__);
	xprt_clear_connecting(xprt);
}

/*
 * xprt_rdma_destroy
 *
 * Destroy the xprt.
 * Free all memory associated with the object, including its own.
 * NOTE: none of the *destroy methods free memory for their top-level
 * objects, even though they may have allocated it (they do free
 * private memory). It's up to the caller to handle it. In this
 * case (RDMA transport), all structure memory is inlined with the
 * struct rpcrdma_xprt.
 */
static void
xprt_rdma_destroy(struct rpc_xprt *xprt)
{
	struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
	int rc;

	dprintk("RPC:       %s: called\n", __func__);

	cancel_delayed_work(&r_xprt->rdma_connect);
	flush_scheduled_work();

	xprt_clear_connected(xprt);

	rpcrdma_buffer_destroy(&r_xprt->rx_buf);
	rc = rpcrdma_ep_destroy(&r_xprt->rx_ep, &r_xprt->rx_ia);
	if (rc)
		dprintk("RPC:       %s: rpcrdma_ep_destroy returned %i\n",
			__func__, rc);
	rpcrdma_ia_close(&r_xprt->rx_ia);

	xprt_rdma_free_addresses(xprt);

	kfree(xprt->slot);
	xprt->slot = NULL;
	kfree(xprt);

	dprintk("RPC:       %s: returning\n", __func__);

	module_put(THIS_MODULE);
}

/**
 * xprt_setup_rdma - Set up transport to use RDMA
 *
 * @args: rpc transport arguments
 */
static struct rpc_xprt *
xprt_setup_rdma(struct xprt_create *args)
{
	struct rpcrdma_create_data_internal cdata;
	struct rpc_xprt *xprt;
	struct rpcrdma_xprt *new_xprt;
	struct rpcrdma_ep *new_ep;
	struct sockaddr_in *sin;
	int rc;

	if (args->addrlen > sizeof(xprt->addr)) {
		dprintk("RPC:       %s: address too large\n", __func__);
		return ERR_PTR(-EBADF);
	}

	xprt = kzalloc(sizeof(struct rpcrdma_xprt), GFP_KERNEL);
	if (xprt == NULL) {
		dprintk("RPC:       %s: couldn't allocate rpcrdma_xprt\n",
			__func__);
		return ERR_PTR(-ENOMEM);
	}

	xprt->max_reqs = xprt_rdma_slot_table_entries;
	xprt->slot = kcalloc(xprt->max_reqs,
				sizeof(struct rpc_rqst), GFP_KERNEL);
	if (xprt->slot == NULL) {
		dprintk("RPC:       %s: couldn't allocate %d slots\n",
			__func__, xprt->max_reqs);
		kfree(xprt);
		return ERR_PTR(-ENOMEM);
	}

	/* 60 second timeout, no retries */
	xprt_set_timeout(&xprt->timeout, 0, 60UL * HZ);
	xprt->bind_timeout = (60U * HZ);
	xprt->connect_timeout = (60U * HZ);
	xprt->reestablish_timeout = (5U * HZ);
	xprt->idle_timeout = (5U * 60 * HZ);

	xprt->resvport = 0;		/* privileged port not needed */
	xprt->tsh_size = 0;		/* RPC-RDMA handles framing */
	xprt->max_payload = RPCRDMA_MAX_DATA_SEGS * PAGE_SIZE;
	xprt->ops = &xprt_rdma_procs;

	/*
	 * Set up RDMA-specific connect data.
	 */

	/* Put server RDMA address in local cdata */
	memcpy(&cdata.addr, args->dstaddr, args->addrlen);

	/* Ensure xprt->addr holds valid server TCP (not RDMA)
	 * address, for any side protocols which peek at it */
	xprt->prot = IPPROTO_TCP;
	xprt->addrlen = args->addrlen;
	memcpy(&xprt->addr, &cdata.addr, xprt->addrlen);

	sin = (struct sockaddr_in *)&cdata.addr;
	if (ntohs(sin->sin_port) != 0)
		xprt_set_bound(xprt);

	dprintk("RPC:       %s: %u.%u.%u.%u:%u\n", __func__,
			NIPQUAD(sin->sin_addr.s_addr), ntohs(sin->sin_port));

	/* Set max requests */
	cdata.max_requests = xprt->max_reqs;

	/* Set some length limits */
	cdata.rsize = RPCRDMA_MAX_SEGS * PAGE_SIZE; /* RDMA write max */
	cdata.wsize = RPCRDMA_MAX_SEGS * PAGE_SIZE; /* RDMA read max */

	cdata.inline_wsize = xprt_rdma_max_inline_write;
	if (cdata.inline_wsize > cdata.wsize)
		cdata.inline_wsize = cdata.wsize;

	cdata.inline_rsize = xprt_rdma_max_inline_read;
	if (cdata.inline_rsize > cdata.rsize)
		cdata.inline_rsize = cdata.rsize;

	cdata.padding = xprt_rdma_inline_write_padding;

	/*
	 * Create new transport instance, which includes initialized
	 *  o ia
	 *  o endpoint
	 *  o buffers
	 */

	new_xprt = rpcx_to_rdmax(xprt);

	rc = rpcrdma_ia_open(new_xprt, (struct sockaddr *) &cdata.addr,
				xprt_rdma_memreg_strategy);
	if (rc)
		goto out1;

	/*
	 * initialize and create ep
	 */
	new_xprt->rx_data = cdata;
	new_ep = &new_xprt->rx_ep;
	new_ep->rep_remote_addr = cdata.addr;

	rc = rpcrdma_ep_create(&new_xprt->rx_ep,
				&new_xprt->rx_ia, &new_xprt->rx_data);
	if (rc)