usr/src/uts/common/io/mac/mac_hio.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 /*
  27  * MAC Hybrid I/O related code.
  28  */
  29
  30 #include <sys/types.h>
  31 #include <sys/sdt.h>
  32 #include <sys/mac.h>
  33 #include <sys/mac_impl.h>
  34 #include <sys/mac_client_impl.h>
  35 #include <sys/mac_client_priv.h>
  36 #include <sys/mac_soft_ring.h>
  37
  38
  39 /*
  40  * Return the number of shares supported by the specified MAC.
  41  */
  42 int
  43 mac_share_capable(mac_handle_t mh)
  44 {
  45         mac_impl_t *mip = (mac_impl_t *)mh;
  46
  47         return (mip->mi_share_capab.ms_snum);
  48 }
  49
  50
  51 /*
  52  * Allocate a share to the specified MAC client. Invoked when
  53  * mac_client_open() is invoked with MAC_OPEN_FLAGS_SHARES_DESIRED set.
  54  */
  55 void
  56 i_mac_share_alloc(mac_client_impl_t *mcip)
  57 {
  58         mac_impl_t *mip = mcip->mci_mip;
  59         int rv;
  60
  61         i_mac_perim_enter(mip);
  62
  63         ASSERT(mcip->mci_share == (uintptr_t)NULL);
  64
  65         if (mac_share_capable((mac_handle_t)mcip->mci_mip) == 0) {
  66                 DTRACE_PROBE1(i__mac__share__alloc__not__sup,
  67                     mac_client_impl_t *, mcip);
  68                 i_mac_perim_exit(mip);
  69                 return;
  70         }
  71
  72         rv = mip->mi_share_capab.ms_salloc(mip->mi_share_capab.ms_handle,
  73             &mcip->mci_share);
  74         DTRACE_PROBE3(i__mac__share__alloc, mac_client_impl_t *, mcip,
  75             int, rv, mac_share_handle_t, mcip->mci_share);
  76
  77         mcip->mci_state_flags &= ~MCIS_SHARE_BOUND;
  78
  79         i_mac_perim_exit(mip);
  80 }
  81
  82
  83 /*
  84  * Free a share previously allocated through i_mac_share_alloc().
  85  * Safely handles the case when no shares were allocated to the MAC client.
  86  */
  87 void
  88 i_mac_share_free(mac_client_impl_t *mcip)
  89 {
  90         mac_impl_t *mip = mcip->mci_mip;
  91
  92         i_mac_perim_enter(mip);
  93
  94         /* MAC clients are required to unbind they shares before freeing them */
  95         ASSERT((mcip->mci_state_flags & MCIS_SHARE_BOUND) == 0);
  96
  97         if (mcip->mci_share == (uintptr_t)NULL) {
  98                 i_mac_perim_exit(mip);
  99                 return;
 100         }
 101
 102         mip->mi_share_capab.ms_sfree(mcip->mci_share);
 103         i_mac_perim_exit(mip);
 104 }
 105
 106
 107 /*
 108  * Bind a share. After this operation the rings that were associated
 109  * with the MAC client are mapped directly into the corresponding
 110  * guest domain.
 111  */
 112 int
 113 mac_share_bind(mac_client_handle_t mch, uint64_t cookie, uint64_t *rcookie)
 114 {
 115         mac_client_impl_t *mcip = (mac_client_impl_t *)mch;
 116         mac_impl_t *mip = mcip->mci_mip;
 117         int rv;
 118
 119         i_mac_perim_enter(mip);
 120
 121         if (mcip->mci_share == (uintptr_t)NULL) {
 122                 i_mac_perim_exit(mip);
 123                 return (ENOTSUP);
 124         }
 125
 126         ASSERT((mcip->mci_state_flags & MCIS_SHARE_BOUND) == 0);
 127
 128         /*
 129          * Temporarly suspend the TX traffic for that client to make sure
 130          * there are no in flight packets through a transmit ring
 131          * which is being bound to another domain.
 132          */
 133         mac_tx_client_quiesce(mch);
 134
 135         /*
 136          * For the receive path, no traffic will be sent up through
 137          * the rings to the IO domain. For TX, we need to ensure
 138          * that traffic sent by the MAC client are sent through
 139          * the default ring.
 140          *
 141          * For the transmit path we ensure that packets are sent through the
 142          * default ring if the share of the MAC client is bound, see MAC_TX().
 143          */
 144
 145         rv = mip->mi_share_capab.ms_sbind(mcip->mci_share, cookie, rcookie);
 146         if (rv == 0)
 147                 mcip->mci_state_flags |= MCIS_SHARE_BOUND;
 148
 149         /*
 150          * Resume transmit traffic for the MAC client.
 151          */
 152         mac_tx_client_restart(mch);
 153
 154         i_mac_perim_exit(mip);
 155
 156         return (rv);
 157 }
 158
 159
 160 /*
 161  * Unbind a share.
 162  */
 163 void
 164 mac_share_unbind(mac_client_handle_t mch)
 165 {
 166         mac_client_impl_t *mcip = (mac_client_impl_t *)mch;
 167         mac_impl_t *mip = mcip->mci_mip;
 168
 169         i_mac_perim_enter(mip);
 170
 171         if (mcip->mci_share == (uintptr_t)NULL) {
 172                 i_mac_perim_exit(mip);
 173                 return;
 174         }
 175
 176         mip->mi_share_capab.ms_sunbind(mcip->mci_share);
 177
 178         mcip->mci_state_flags &= ~MCIS_SHARE_BOUND;
 179
 180         /*
 181          * If the link state changed while the share was bound, the
 182          * soft rings fanout associated with the client would have not
 183          * been updated by mac_fanout_recompute(). Do the check here
 184          * now that the share has been unbound.
 185          */
 186         mac_fanout_recompute_client(mcip, NULL);
 187
 188         i_mac_perim_exit(mip);
 189 }