drivers/misc/mic/scif/scif_fd.c

   1 /*
   2  * Intel MIC Platform Software Stack (MPSS)
   3  *
   4  * Copyright(c) 2014 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * Intel SCIF driver.
  16  *
  17  */
  18 #include "scif_main.h"
  19
  20 static int scif_fdopen(struct inode *inode, struct file *f)
  21 {
  22         struct scif_endpt *priv = scif_open();
  23
  24         if (!priv)
  25                 return -ENOMEM;
  26         f->private_data = priv;
  27         return 0;
  28 }
  29
  30 static int scif_fdclose(struct inode *inode, struct file *f)
  31 {
  32         struct scif_endpt *priv = f->private_data;
  33
  34         return scif_close(priv);
  35 }
  36
  37 static int scif_fdflush(struct file *f, fl_owner_t id)
  38 {
  39         struct scif_endpt *ep = f->private_data;
  40
  41         spin_lock(&ep->lock);
  42         /*
  43          * The listening endpoint stashes the open file information before
  44          * waiting for incoming connections. The release callback would never be
  45          * called if the application closed the endpoint, while waiting for
  46          * incoming connections from a separate thread since the file descriptor
  47          * reference count is bumped up in the accept IOCTL. Call the flush
  48          * routine if the id matches the endpoint open file information so that
  49          * the listening endpoint can be woken up and the fd released.
  50          */
  51         if (ep->files == id)
  52                 __scif_flush(ep);
  53         spin_unlock(&ep->lock);
  54         return 0;
  55 }
  56
  57 static __always_inline void scif_err_debug(int err, const char *str)
  58 {
  59         /*
  60          * ENOTCONN is a common uninteresting error which is
  61          * flooding debug messages to the console unnecessarily.
  62          */
  63         if (err < 0 && err != -ENOTCONN)
  64                 dev_dbg(scif_info.mdev.this_device, "%s err %d\n", str, err);
  65 }
  66
  67 static long scif_fdioctl(struct file *f, unsigned int cmd, unsigned long arg)
  68 {
  69         struct scif_endpt *priv = f->private_data;
  70         void __user *argp = (void __user *)arg;
  71         int err = 0;
  72         struct scifioctl_msg request;
  73         bool non_block = false;
  74
  75         non_block = !!(f->f_flags & O_NONBLOCK);
  76
  77         switch (cmd) {
  78         case SCIF_BIND:
  79         {
  80                 int pn;
  81
  82                 if (copy_from_user(&pn, argp, sizeof(pn)))
  83                         return -EFAULT;
  84
  85                 pn = scif_bind(priv, pn);
  86                 if (pn < 0)
  87                         return pn;
  88
  89                 if (copy_to_user(argp, &pn, sizeof(pn)))
  90                         return -EFAULT;
  91
  92                 return 0;
  93         }
  94         case SCIF_LISTEN:
  95                 return scif_listen(priv, arg);
  96         case SCIF_CONNECT:
  97         {
  98                 struct scifioctl_connect req;
  99                 struct scif_endpt *ep = (struct scif_endpt *)priv;
 100
 101                 if (copy_from_user(&req, argp, sizeof(req)))
 102                         return -EFAULT;
 103
 104                 err = __scif_connect(priv, &req.peer, non_block);
 105                 if (err < 0)
 106                         return err;
 107
 108                 req.self.node = ep->port.node;
 109                 req.self.port = ep->port.port;
 110
 111                 if (copy_to_user(argp, &req, sizeof(req)))
 112                         return -EFAULT;
 113
 114                 return 0;
 115         }
 116         /*
 117          * Accept is done in two halves.  The request ioctl does the basic
 118          * functionality of accepting the request and returning the information
 119          * about it including the internal ID of the end point.  The register
 120          * is done with the internal ID on a new file descriptor opened by the
 121          * requesting process.
 122          */
 123         case SCIF_ACCEPTREQ:
 124         {
 125                 struct scifioctl_accept request;
 126                 scif_epd_t *ep = (scif_epd_t *)&request.endpt;
 127
 128                 if (copy_from_user(&request, argp, sizeof(request)))
 129                         return -EFAULT;
 130
 131                 err = scif_accept(priv, &request.peer, ep, request.flags);
 132                 if (err < 0)
 133                         return err;
 134
 135                 if (copy_to_user(argp, &request, sizeof(request))) {
 136                         scif_close(*ep);
 137                         return -EFAULT;
 138                 }
 139                 /*
 140                  * Add to the list of user mode eps where the second half
 141                  * of the accept is not yet completed.
 142                  */
 143                 spin_lock(&scif_info.eplock);
 144                 list_add_tail(&((*ep)->miacceptlist), &scif_info.uaccept);
 145                 list_add_tail(&((*ep)->liacceptlist), &priv->li_accept);
 146                 (*ep)->listenep = priv;
 147                 priv->acceptcnt++;
 148                 spin_unlock(&scif_info.eplock);
 149
 150                 return 0;
 151         }
 152         case SCIF_ACCEPTREG:
 153         {
 154                 struct scif_endpt *priv = f->private_data;
 155                 struct scif_endpt *newep;
 156                 struct scif_endpt *lisep;
 157                 struct scif_endpt *fep = NULL;
 158                 struct scif_endpt *tmpep;
 159                 struct list_head *pos, *tmpq;
 160
 161                 /* Finally replace the pointer to the accepted endpoint */
 162                 if (copy_from_user(&newep, argp, sizeof(void *)))
 163                         return -EFAULT;
 164
 165                 /* Remove form the user accept queue */
 166                 spin_lock(&scif_info.eplock);
 167                 list_for_each_safe(pos, tmpq, &scif_info.uaccept) {
 168                         tmpep = list_entry(pos,
 169                                            struct scif_endpt, miacceptlist);
 170                         if (tmpep == newep) {
 171                                 list_del(pos);
 172                                 fep = tmpep;
 173                                 break;
 174                         }
 175                 }
 176
 177                 if (!fep) {
 178                         spin_unlock(&scif_info.eplock);
 179                         return -ENOENT;
 180                 }
 181
 182                 lisep = newep->listenep;
 183                 list_for_each_safe(pos, tmpq, &lisep->li_accept) {
 184                         tmpep = list_entry(pos,
 185                                            struct scif_endpt, liacceptlist);
 186                         if (tmpep == newep) {
 187                                 list_del(pos);
 188                                 lisep->acceptcnt--;
 189                                 break;
 190                         }
 191                 }
 192
 193                 spin_unlock(&scif_info.eplock);
 194
 195                 /* Free the resources automatically created from the open. */
 196                 scif_teardown_ep(priv);
 197                 scif_add_epd_to_zombie_list(priv, !SCIF_EPLOCK_HELD);
 198                 f->private_data = newep;
 199                 return 0;
 200         }
 201         case SCIF_SEND:
 202         {
 203                 struct scif_endpt *priv = f->private_data;
 204
 205                 if (copy_from_user(&request, argp,
 206                                    sizeof(struct scifioctl_msg))) {
 207                         err = -EFAULT;
 208                         goto send_err;
 209                 }
 210                 err = scif_user_send(priv, (void __user *)request.msg,
 211                                      request.len, request.flags);
 212                 if (err < 0)
 213                         goto send_err;
 214                 if (copy_to_user(&
 215                                  ((struct scifioctl_msg __user *)argp)->out_len,
 216                                  &err, sizeof(err))) {
 217                         err = -EFAULT;
 218                         goto send_err;
 219                 }
 220                 err = 0;
 221 send_err:
 222                 scif_err_debug(err, "scif_send");
 223                 return err;
 224         }
 225         case SCIF_RECV:
 226         {
 227                 struct scif_endpt *priv = f->private_data;
 228
 229                 if (copy_from_user(&request, argp,
 230                                    sizeof(struct scifioctl_msg))) {
 231                         err = -EFAULT;
 232                         goto recv_err;
 233                 }
 234
 235                 err = scif_user_recv(priv, (void __user *)request.msg,
 236                                      request.len, request.flags);
 237                 if (err < 0)
 238                         goto recv_err;
 239
 240                 if (copy_to_user(&
 241                                  ((struct scifioctl_msg __user *)argp)->out_len,
 242                         &err, sizeof(err))) {
 243                         err = -EFAULT;
 244                         goto recv_err;
 245                 }
 246                 err = 0;
 247 recv_err:
 248                 scif_err_debug(err, "scif_recv");
 249                 return err;
 250         }
 251         case SCIF_GET_NODEIDS:
 252         {
 253                 struct scifioctl_node_ids node_ids;
 254                 int entries;
 255                 u16 *nodes;
 256                 void __user *unodes, *uself;
 257                 u16 self;
 258
 259                 if (copy_from_user(&node_ids, argp, sizeof(node_ids))) {
 260                         err = -EFAULT;
 261                         goto getnodes_err2;
 262                 }
 263
 264                 entries = min_t(int, scif_info.maxid, node_ids.len);
 265                 nodes = kmalloc_array(entries, sizeof(u16), GFP_KERNEL);
 266                 if (entries && !nodes) {
 267                         err = -ENOMEM;
 268                         goto getnodes_err2;
 269                 }
 270                 node_ids.len = scif_get_node_ids(nodes, entries, &self);
 271
 272                 unodes = (void __user *)node_ids.nodes;
 273                 if (copy_to_user(unodes, nodes, sizeof(u16) * entries)) {
 274                         err = -EFAULT;
 275                         goto getnodes_err1;
 276                 }
 277
 278                 uself = (void __user *)node_ids.self;
 279                 if (copy_to_user(uself, &self, sizeof(u16))) {
 280                         err = -EFAULT;
 281                         goto getnodes_err1;
 282                 }
 283
 284                 if (copy_to_user(argp, &node_ids, sizeof(node_ids))) {
 285                         err = -EFAULT;
 286                         goto getnodes_err1;
 287                 }
 288 getnodes_err1:
 289                 kfree(nodes);
 290 getnodes_err2:
 291                 return err;
 292         }
 293         }
 294         return -EINVAL;
 295 }
 296
 297 const struct file_operations scif_fops = {
 298         .open = scif_fdopen,
 299         .release = scif_fdclose,
 300         .unlocked_ioctl = scif_fdioctl,
 301         .flush = scif_fdflush,
 302         .owner = THIS_MODULE,
 303 };