ceph/src/dpdk/lib/librte_power/guest_channel.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <unistd.h>
  37 #include <signal.h>
  38 #include <limits.h>
  39 #include <fcntl.h>
  40 #include <string.h>
  41 #include <errno.h>
  42
  43
  44 #include <rte_log.h>
  45
  46 #include "guest_channel.h"
  47 #include "channel_commands.h"
  48
  49 #define RTE_LOGTYPE_GUEST_CHANNEL RTE_LOGTYPE_USER1
  50
  51 static int global_fds[RTE_MAX_LCORE];
  52
  53 int
  54 guest_channel_host_connect(const char *path, unsigned lcore_id)
  55 {
  56         int flags, ret;
  57         struct channel_packet pkt;
  58         char fd_path[PATH_MAX];
  59         int fd = -1;
  60
  61         if (lcore_id >= RTE_MAX_LCORE) {
  62                 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
  63                                 lcore_id, RTE_MAX_LCORE-1);
  64                 return -1;
  65         }
  66         /* check if path is already open */
  67         if (global_fds[lcore_id] != 0) {
  68                 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is already open with fd %d\n",
  69                                 lcore_id, global_fds[lcore_id]);
  70                 return -1;
  71         }
  72
  73         snprintf(fd_path, PATH_MAX, "%s.%u", path, lcore_id);
  74         RTE_LOG(INFO, GUEST_CHANNEL, "Opening channel '%s' for lcore %u\n",
  75                         fd_path, lcore_id);
  76         fd = open(fd_path, O_RDWR);
  77         if (fd < 0) {
  78                 RTE_LOG(ERR, GUEST_CHANNEL, "Unable to to connect to '%s' with error "
  79                                 "%s\n", fd_path, strerror(errno));
  80                 return -1;
  81         }
  82
  83         flags = fcntl(fd, F_GETFL, 0);
  84         if (flags < 0) {
  85                 RTE_LOG(ERR, GUEST_CHANNEL, "Failed on fcntl get flags for file %s\n",
  86                                 fd_path);
  87                 goto error;
  88         }
  89
  90         flags |= O_NONBLOCK;
  91         if (fcntl(fd, F_SETFL, flags) < 0) {
  92                 RTE_LOG(ERR, GUEST_CHANNEL, "Failed on setting non-blocking mode for "
  93                                 "file %s", fd_path);
  94                 goto error;
  95         }
  96         /* QEMU needs a delay after connection */
  97         sleep(1);
  98
  99         /* Send a test packet, this command is ignored by the host, but a successful
 100          * send indicates that the host endpoint is monitoring.
 101          */
 102         pkt.command = CPU_POWER_CONNECT;
 103         global_fds[lcore_id] = fd;
 104         ret = guest_channel_send_msg(&pkt, lcore_id);
 105         if (ret != 0) {
 106                 RTE_LOG(ERR, GUEST_CHANNEL,
 107                                 "Error on channel '%s' communications test: %s\n",
 108                                 fd_path, ret > 0 ? strerror(ret) :
 109                                 "channel not connected");
 110                 goto error;
 111         }
 112         RTE_LOG(INFO, GUEST_CHANNEL, "Channel '%s' is now connected\n", fd_path);
 113         return 0;
 114 error:
 115         close(fd);
 116         global_fds[lcore_id] = 0;
 117         return -1;
 118 }
 119
 120 int
 121 guest_channel_send_msg(struct channel_packet *pkt, unsigned lcore_id)
 122 {
 123         int ret, buffer_len = sizeof(*pkt);
 124         void *buffer = pkt;
 125
 126         if (lcore_id >= RTE_MAX_LCORE) {
 127                 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
 128                                 lcore_id, RTE_MAX_LCORE-1);
 129                 return -1;
 130         }
 131
 132         if (global_fds[lcore_id] == 0) {
 133                 RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not connected\n");
 134                 return -1;
 135         }
 136         while (buffer_len > 0) {
 137                 ret = write(global_fds[lcore_id], buffer, buffer_len);
 138                 if (ret == buffer_len)
 139                         return 0;
 140                 if (ret == -1) {
 141                         if (errno == EINTR)
 142                                 continue;
 143                         return errno;
 144                 }
 145                 buffer = (char *)buffer + ret;
 146                 buffer_len -= ret;
 147         }
 148         return 0;
 149 }
 150
 151 void
 152 guest_channel_host_disconnect(unsigned lcore_id)
 153 {
 154         if (lcore_id >= RTE_MAX_LCORE) {
 155                 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
 156                                 lcore_id, RTE_MAX_LCORE-1);
 157                 return;
 158         }
 159         if (global_fds[lcore_id] == 0)
 160                 return;
 161         close(global_fds[lcore_id]);
 162         global_fds[lcore_id] = 0;
 163 }