sys/net/netmap/netmap_freebsd.c

   1 /*
   2  * Copyright (C) 2013 Universita` di Pisa. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *   1. Redistributions of source code must retain the above copyright
   8  *      notice, this list of conditions and the following disclaimer.
   9  *   2. Redistributions in binary form must reproduce the above copyright
  10  *      notice, this list of conditions and the following disclaimer in the
  11  *      documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  */
  25
  26 #include <sys/types.h>
  27 #include <sys/module.h>
  28 #include <sys/errno.h>
  29 #include <sys/param.h>  /* defines used in kernel.h */
  30 #include <sys/kernel.h> /* types used in module initialization */
  31 #include <sys/conf.h>   /* DEV_MODULE */
  32
  33 #include <sys/devfs.h>
  34
  35 #include <vm/vm.h>      /* vtophys */
  36 #include <vm/pmap.h>    /* vtophys */
  37 #include <vm/vm_param.h>
  38 #include <vm/vm_object.h>
  39 #include <vm/vm_page.h>
  40 #include <vm/vm_page2.h>
  41 #include <vm/vm_pager.h>
  42
  43
  44 #include <sys/malloc.h>
  45 #include <sys/socket.h> /* sockaddrs */
  46 #include <sys/event.h>
  47 #include <net/if.h>
  48 #include <net/if_var.h>
  49 #include <net/ifq_var.h>
  50 #include <sys/bus.h>    /* bus_dmamap_* */
  51
  52 #include <net/netmap.h>
  53 #include <net/netmap/netmap_kern.h>
  54 #include <net/netmap/netmap_mem2.h>
  55
  56
  57 /* ======================== FREEBSD-SPECIFIC ROUTINES ================== */
  58
  59 /*
  60  * Intercept the rx routine in the standard device driver.
  61  * Second argument is non-zero to intercept, 0 to restore
  62  */
  63 int
  64 netmap_catch_rx(struct netmap_adapter *na, int intercept)
  65 {
  66         struct netmap_generic_adapter *gna = (struct netmap_generic_adapter *)na;
  67         struct ifnet *ifp = na->ifp;
  68
  69         if (intercept) {
  70                 if (gna->save_if_input) {
  71                         D("cannot intercept again");
  72                         return EINVAL; /* already set */
  73                 }
  74                 gna->save_if_input = ifp->if_input;
  75                 ifp->if_input = generic_rx_handler;
  76         } else {
  77                 if (!gna->save_if_input){
  78                         D("cannot restore");
  79                         return EINVAL;  /* not saved */
  80                 }
  81                 ifp->if_input = gna->save_if_input;
  82                 gna->save_if_input = NULL;
  83         }
  84
  85         return 0;
  86 }
  87
  88 /*
  89  * Intercept the packet steering routine in the tx path,
  90  * so that we can decide which queue is used for an mbuf.
  91  * Second argument is non-zero to intercept, 0 to restore.
  92  *
  93  * XXX see if FreeBSD has such a mechanism
  94  */
  95 void
  96 netmap_catch_packet_steering(struct netmap_generic_adapter *na, int enable)
  97 {
  98         if (enable) {
  99         } else {
 100         }
 101 }
 102
 103 /* Transmit routine used by generic_netmap_txsync(). Returns 0 on success
 104  * and non-zero on error (which may be packet drops or other errors).
 105  * addr and len identify the netmap buffer, m is the (preallocated)
 106  * mbuf to use for transmissions.
 107  *
 108  * We should add a reference to the mbuf so the m_freem() at the end
 109  * of the transmission does not consume resources.
 110  *
 111  * On FreeBSD, and on multiqueue cards, we can force the queue using
 112  *      if ((m->m_flags & M_FLOWID) != 0)
 113  *              i = m->m_pkthdr.flowid % adapter->num_queues;
 114  *      else
 115  *              i = curcpu % adapter->num_queues;
 116  *
 117  */
 118 int
 119 generic_xmit_frame(struct ifnet *ifp, struct mbuf *m,
 120         void *addr, u_int len, u_int ring_nr)
 121 {
 122         int ret;
 123
 124         m->m_len = m->m_pkthdr.len = 0;
 125
 126         // copy data to the mbuf
 127         m_copyback(m, 0, len, addr);
 128
 129 #if 0
 130         // inc refcount. We are alone, so we can skip the atomic
 131         atomic_fetchadd_int(m->m_ext.ref_cnt, 1);
 132         m->m_flags |= M_FLOWID;
 133 #endif
 134         m->m_pkthdr.hash = ring_nr;     /* XXX probably not accurate */
 135         m->m_pkthdr.rcvif = ifp; /* used for tx notification */
 136         ret = ifq_dispatch(ifp, m, NULL);
 137         return ret;
 138 }
 139
 140 /*
 141  * The following two functions are empty until we have a generic
 142  * way to extract the info from the ifp
 143  */
 144 int
 145 generic_find_num_desc(struct ifnet *ifp, unsigned int *tx, unsigned int *rx)
 146 {
 147         D("called");
 148         return 0;
 149 }
 150
 151 void
 152 generic_find_num_queues(struct ifnet *ifp, u_int *txq, u_int *rxq)
 153 {
 154         D("called");
 155         *txq = 1;
 156         *rxq = 1;
 157 }
 158
 159 void netmap_mitigation_init(struct netmap_generic_adapter *na)
 160 {
 161         ND("called");
 162         na->mit_pending = 0;
 163 }
 164
 165
 166 void netmap_mitigation_start(struct netmap_generic_adapter *na)
 167 {
 168         ND("called");
 169 }
 170
 171 void netmap_mitigation_restart(struct netmap_generic_adapter *na)
 172 {
 173         ND("called");
 174 }
 175
 176 int netmap_mitigation_active(struct netmap_generic_adapter *na)
 177 {
 178         ND("called");
 179         return 0;
 180 }
 181
 182 void netmap_mitigation_cleanup(struct netmap_generic_adapter *na)
 183 {
 184         ND("called");
 185 }
 186
 187
 188 /*
 189  * In order to track whether pages are still mapped, we hook into
 190  * the standard cdev_pager and intercept the constructor and
 191  * destructor.
 192  */
 193
 194 struct netmap_vm_handle_t {
 195         struct cdev             *dev;
 196         struct netmap_priv_d    *priv;
 197 };
 198
 199 static int
 200 netmap_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
 201     vm_ooffset_t foff, struct ucred *cred, u_short *color)
 202 {
 203         struct netmap_vm_handle_t *vmh = handle;
 204         (void)vmh;
 205         D("handle %p size %jd prot %d foff %jd",
 206                 handle, (intmax_t)size, prot, (intmax_t)foff);
 207 #if 0
 208         dev_ref(vmh->dev);
 209 #endif
 210         return 0;
 211 }
 212
 213
 214 static void
 215 netmap_dev_pager_dtor(void *handle)
 216 {
 217         struct netmap_vm_handle_t *vmh = handle;
 218         struct cdev *dev = vmh->dev;
 219         struct netmap_priv_d *priv = vmh->priv;
 220         (void)dev;
 221         D("handle %p", handle);
 222         netmap_dtor(priv);
 223         kfree(vmh, M_DEVBUF);
 224 #if 0
 225         dev_rel(dev);
 226 #endif
 227 }
 228
 229 MALLOC_DEFINE(M_FICT_PAGES, "", "");
 230
 231 static inline vm_page_t
 232 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr)
 233 {
 234         vm_page_t m;
 235
 236         m = kmalloc(sizeof(struct vm_page), M_FICT_PAGES,
 237             M_WAITOK | M_ZERO);
 238         vm_page_initfake(m, paddr, memattr);
 239         return (m);
 240 }
 241
 242 static inline void
 243 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
 244 {
 245         KASSERT((m->flags & PG_FICTITIOUS) != 0,
 246             ("vm_page_updatefake: bad page %p", m));
 247         m->phys_addr = paddr;
 248         pmap_page_set_memattr(m, memattr);
 249 }
 250
 251 static int
 252 netmap_dev_pager_fault(vm_object_t object, vm_ooffset_t offset,
 253         int prot, vm_page_t *mres)
 254 {
 255         struct netmap_vm_handle_t *vmh = object->handle;
 256         struct netmap_priv_d *priv = vmh->priv;
 257         vm_paddr_t paddr;
 258         vm_page_t page;
 259         vm_memattr_t memattr;
 260         vm_pindex_t pidx;
 261
 262         ND("object %p offset %jd prot %d mres %p",
 263                         object, (intmax_t)offset, prot, mres);
 264         memattr = object->memattr;
 265         pidx = OFF_TO_IDX(offset);
 266         paddr = netmap_mem_ofstophys(priv->np_mref, offset);
 267         if (paddr == 0)
 268                 return VM_PAGER_FAIL;
 269
 270         if (((*mres)->flags & PG_FICTITIOUS) != 0) {
 271                 /*
 272                  * If the passed in result page is a fake page, update it with
 273                  * the new physical address.
 274                  */
 275                 page = *mres;
 276                 vm_page_updatefake(page, paddr, memattr);
 277         } else {
 278                 /*
 279                  * Replace the passed in reqpage page with our own fake page and
 280                  * free up the all of the original pages.
 281                  */
 282 #ifndef VM_OBJECT_WUNLOCK       /* FreeBSD < 10.x */
 283 #define VM_OBJECT_WUNLOCK VM_OBJECT_UNLOCK
 284 #define VM_OBJECT_WLOCK VM_OBJECT_LOCK
 285 #endif /* VM_OBJECT_WUNLOCK */
 286
 287                 VM_OBJECT_WUNLOCK(object);
 288                 page = vm_page_getfake(paddr, memattr);
 289                 VM_OBJECT_WLOCK(object);
 290                 vm_page_free(*mres);
 291                 *mres = page;
 292                 vm_page_insert(page, object, pidx);
 293         }
 294         page->valid = VM_PAGE_BITS_ALL;
 295         return (VM_PAGER_OK);
 296 }
 297
 298
 299 static struct cdev_pager_ops netmap_cdev_pager_ops = {
 300         .cdev_pg_ctor = netmap_dev_pager_ctor,
 301         .cdev_pg_dtor = netmap_dev_pager_dtor,
 302         .cdev_pg_fault = netmap_dev_pager_fault,
 303 };
 304
 305
 306 static int
 307 netmap_mmap_single(struct dev_mmap_single_args *ap)
 308 {
 309         int error;
 310         struct cdev *cdev = ap->a_head.a_dev;
 311         vm_ooffset_t *foff = ap->a_offset;
 312         vm_object_t *objp = ap->a_object;
 313         vm_size_t objsize = ap->a_size;
 314         struct netmap_vm_handle_t *vmh;
 315         struct netmap_priv_d *priv;
 316         int prot = ap->a_nprot;
 317         vm_object_t obj;
 318
 319         D("cdev %p foff %jd size %jd objp %p prot %d", cdev,
 320             (intmax_t )*foff, (intmax_t )objsize, objp, prot);
 321
 322         vmh = kmalloc(sizeof(struct netmap_vm_handle_t), M_DEVBUF,
 323                               M_NOWAIT | M_ZERO);
 324         if (vmh == NULL)
 325                 return ENOMEM;
 326         vmh->dev = cdev;
 327
 328         NMG_LOCK();
 329         error = devfs_get_cdevpriv(ap->a_fp, (void**)&priv);
 330         if (error)
 331                 goto err_unlock;
 332         vmh->priv = priv;
 333         priv->np_refcount++;
 334         NMG_UNLOCK();
 335
 336         error = netmap_get_memory(priv);
 337         if (error)
 338                 goto err_deref;
 339
 340         obj = cdev_pager_allocate(vmh, OBJT_DEVICE,
 341                 &netmap_cdev_pager_ops, objsize, prot,
 342                 *foff, NULL);
 343         if (obj == NULL) {
 344                 D("cdev_pager_allocate failed");
 345                 error = EINVAL;
 346                 goto err_deref;
 347         }
 348
 349         *objp = obj;
 350         return 0;
 351
 352 err_deref:
 353         NMG_LOCK();
 354         priv->np_refcount--;
 355 err_unlock:
 356         NMG_UNLOCK();
 357 // err:
 358         kfree(vmh, M_DEVBUF);
 359         return error;
 360 }
 361
 362
 363 // XXX can we remove this ?
 364 static int
 365 netmap_close(struct dev_close_args *ap)
 366 {
 367         if (netmap_verbose)
 368                 D("dev %p fflag 0x%x devtype %d",
 369                         ap->a_head.a_dev, ap->a_fflag, ap->a_devtype);
 370         return 0;
 371 }
 372
 373
 374 static int
 375 netmap_open(struct dev_open_args *ap)
 376 {
 377         struct netmap_priv_d *priv;
 378         int error;
 379
 380         // XXX wait or nowait ?
 381         priv = kmalloc(sizeof(struct netmap_priv_d), M_DEVBUF,
 382                               M_NOWAIT | M_ZERO);
 383         if (priv == NULL)
 384                 return ENOMEM;
 385
 386         error = devfs_set_cdevpriv(ap->a_fp, priv, netmap_dtor);
 387         if (error)
 388                 return error;
 389
 390         priv->np_refcount = 1;
 391
 392         return 0;
 393 }
 394
 395
 396 struct dev_ops netmap_cdevsw = {
 397         { "netmap", 0, 0 },
 398         .d_open = netmap_open,
 399         .d_mmap_single = netmap_mmap_single,
 400         .d_ioctl = netmap_ioctl,
 401         .d_kqfilter = netmap_kqfilter,
 402         .d_close = netmap_close,
 403 };
 404
 405
 406 /*
 407  * Kernel entry point.
 408  *
 409  * Initialize/finalize the module and return.
 410  *
 411  * Return 0 on success, errno on failure.
 412  */
 413 static int
 414 netmap_loader(__unused struct module *module, int event, __unused void *arg)
 415 {
 416         int error = 0;
 417
 418         switch (event) {
 419         case MOD_LOAD:
 420                 error = netmap_init();
 421                 break;
 422
 423         case MOD_UNLOAD:
 424                 netmap_fini();
 425                 break;
 426
 427         default:
 428                 error = EOPNOTSUPP;
 429                 break;
 430         }
 431
 432         return (error);
 433 }
 434
 435
 436 DEV_MODULE(netmap, netmap_loader, NULL);