sys/netproto/atm/atm_stack.h

   1 /*
   2  *
   3  * ===================================
   4  * HARP  |  Host ATM Research Platform
   5  * ===================================
   6  *
   7  *
   8  * This Host ATM Research Platform ("HARP") file (the "Software") is
   9  * made available by Network Computing Services, Inc. ("NetworkCS")
  10  * "AS IS".  NetworkCS does not provide maintenance, improvements or
  11  * support of any kind.
  12  *
  13  * NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
  14  * INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
  15  * AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
  16  * SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
  17  * In no event shall NetworkCS be responsible for any damages, including
  18  * but not limited to consequential damages, arising from or relating to
  19  * any use of the Software or related support.
  20  *
  21  * Copyright 1994-1998 Network Computing Services, Inc.
  22  *
  23  * Copies of this Software may be made, however, the above copyright
  24  * notice must be reproduced on all copies.
  25  *
  26  *      @(#) $FreeBSD: src/sys/netatm/atm_stack.h,v 1.2 1999/08/28 00:48:38 peter Exp $
  27  *      @(#) $DragonFly: src/sys/netproto/atm/atm_stack.h,v 1.3 2003/08/23 10:06:21 rob Exp $
  28  *
  29  */
  30
  31 /*
  32  * Core ATM Services
  33  * -----------------
  34  *
  35  * ATM Stack definitions
  36  *
  37  */
  38
  39 #ifndef _NETATM_ATM_STACK_H
  40 #define _NETATM_ATM_STACK_H
  41
  42 #ifdef ATM_KERNEL
  43 /*
  44  * Structure used to define a kernel-provided ATM stack service and its
  45  * associated entry points.  Each stack service provider must register
  46  * themselves before they will be used.  ATM stack service providers include
  47  * kernel modules (both linked and loaded) and device drivers, which must list
  48  * (via its atm_pif) any of its available hardware-supplied stack services
  49  * (such as on-card AAL processing).
  50  */
  51 struct stack_defn {
  52         struct stack_defn *sd_next;     /* Next in registry list */
  53         Sap_t           sd_sap;         /* Stack instance SAP */
  54         u_char          sd_flag;        /* Flags (see below) */
  55 /* Exported functions */
  56         int             (*sd_inst)      /* Stack instantiation */
  57                                 (struct stack_defn **, Atm_connvc *);
  58         void            (*sd_lower)     /* Lower (from above) command handler */
  59                                 (int, void *, int, int);
  60         void            (*sd_upper)     /* Upper (from below) command handler */
  61                                 (int, void *, int, int);
  62 /* Variables used during stack instantiation */
  63         void            *sd_toku;       /* Stack service instance token */
  64 };
  65
  66 /*
  67  * Stack Service Flags
  68  */
  69 #define SDF_TERM        0x01            /* Terminal (to lowest layer) service */
  70
  71
  72 /*
  73  * Stack Specification List
  74  *
  75  * The list names the stack services and their layering relationships in
  76  * order to construct a stack to provide the protocol services defined
  77  * by the list.  The list is ordered starting from the stack service
  78  * interfacing with the user "down" to the ATM cell service.
  79  */
  80 #define STACK_CNT       8               /* Max services in a stack list */
  81 struct stack_list {
  82         Sap_t           sl_sap[STACK_CNT];      /* Stack service SAP list */
  83 };
  84
  85
  86 /*
  87  * Structure used during the construction and instantiation of a stack
  88  * instance from a supplied stack list.  It contains pointers to the stack
  89  * service definitions which will be used to implement the stack.  The first
  90  * element in the array is reserved for the user's "stack service".
  91  */
  92 struct stack_inst {
  93         struct stack_defn *si_srvc[STACK_CNT+1];        /* Assigned services */
  94 };
  95
  96
  97 /*
  98  * Macros to update buffer headroom values during stack instantiation.
  99  *
 100  * These values are advisory, i.e. every service must verify the amount
 101  * of available space in input/output messages and allocate new buffers
 102  * if needed.
 103  *
 104  * The 'maximum' and 'minimum' values used below may be chosen by a
 105  * service to reflect the typical, expected message traffic pattern
 106  * for a specific connection.
 107  *
 108  * The macro arguments are:
 109  *      cvp = pointer to connection vcc;
 110  *      hi = maximum amount of buffer headroom required by the current
 111  *           service during input message processing;
 112  *      si = minimum amount of buffer data stripped off the front
 113  *           of an input message by the current service;
 114  *      ho = maximum amount of buffer headroom required by the current
 115  *           service during output message processing;
 116  *      ao = maximum amount of buffer data added to the front
 117  *           of an output message by the current service;
 118  */
 119 #define HEADIN(cvp, hi, si)                                     \
 120 {                                                               \
 121         short   t = (cvp)->cvc_attr.headin - (si);              \
 122         t = (t >= (hi)) ? t : (hi);                             \
 123         (cvp)->cvc_attr.headin = roundup(t, sizeof(long));      \
 124 }
 125
 126 #define HEADOUT(cvp, ho, ao)                                    \
 127 {                                                               \
 128         short   t = (cvp)->cvc_attr.headout + (ao);             \
 129         t = (t >= (ho)) ? t : (ho);                             \
 130         (cvp)->cvc_attr.headout = roundup(t, sizeof(long));     \
 131 }
 132
 133
 134 /*
 135  * Stack command codes - All stack command codes are specific to the
 136  * defined stack SAP across which the command is used.  Command values 0-15
 137  * are reserved for any common codes, which all stack SAPs must support.
 138  */
 139 #define STKCMD(s, d, v) (((s) << 16) | (d) | (v))
 140 #define STKCMD_DOWN     0
 141 #define STKCMD_UP       0x00008000
 142 #define STKCMD_SAP_MASK 0xffff0000
 143 #define STKCMD_VAL_MASK 0x00007fff
 144
 145 /* Common command values (0-15) */
 146 #define CCV_INIT        1               /* DOWN */
 147 #define CCV_TERM        2               /* DOWN */
 148
 149 /* SAP_ATM */
 150 #define ATM_INIT                STKCMD(SAP_ATM, STKCMD_DOWN, CCV_INIT)
 151 #define ATM_TERM                STKCMD(SAP_ATM, STKCMD_DOWN, CCV_TERM)
 152 #define ATM_DATA_REQ            STKCMD(SAP_ATM, STKCMD_DOWN, 16)
 153 #define ATM_DATA_IND            STKCMD(SAP_ATM, STKCMD_UP, 17)
 154
 155 /* SAP_SAR */
 156 #define SAR_INIT                STKCMD(SAP_SAR, STKCMD_DOWN, CCV_INIT)
 157 #define SAR_TERM                STKCMD(SAP_SAR, STKCMD_DOWN, CCV_TERM)
 158 #define SAR_UNITDATA_INV        STKCMD(SAP_SAR, STKCMD_DOWN, 16)
 159 #define SAR_UNITDATA_SIG        STKCMD(SAP_SAR, STKCMD_UP, 17)
 160 #define SAR_UABORT_INV          STKCMD(SAP_SAR, STKCMD_DOWN, 18)
 161 #define SAR_UABORT_SIG          STKCMD(SAP_SAR, STKCMD_UP, 19)
 162 #define SAR_PABORT_SIG          STKCMD(SAP_SAR, STKCMD_UP, 20)
 163
 164 /* SAP_CPCS */
 165 #define CPCS_INIT               STKCMD(SAP_CPCS, STKCMD_DOWN, CCV_INIT)
 166 #define CPCS_TERM               STKCMD(SAP_CPCS, STKCMD_DOWN, CCV_TERM)
 167 #define CPCS_UNITDATA_INV       STKCMD(SAP_CPCS, STKCMD_DOWN, 16)
 168 #define CPCS_UNITDATA_SIG       STKCMD(SAP_CPCS, STKCMD_UP, 17)
 169 #define CPCS_UABORT_INV         STKCMD(SAP_CPCS, STKCMD_DOWN, 18)
 170 #define CPCS_UABORT_SIG         STKCMD(SAP_CPCS, STKCMD_UP, 19)
 171 #define CPCS_PABORT_SIG         STKCMD(SAP_CPCS, STKCMD_UP, 20)
 172
 173 /* SAP_SSCOP */
 174 #define SSCOP_INIT              STKCMD(SAP_SSCOP, STKCMD_DOWN, CCV_INIT)
 175 #define SSCOP_TERM              STKCMD(SAP_SSCOP, STKCMD_DOWN, CCV_TERM)
 176 #define SSCOP_ESTABLISH_REQ     STKCMD(SAP_SSCOP, STKCMD_DOWN, 16)
 177 #define SSCOP_ESTABLISH_IND     STKCMD(SAP_SSCOP, STKCMD_UP, 17)
 178 #define SSCOP_ESTABLISH_RSP     STKCMD(SAP_SSCOP, STKCMD_DOWN, 18)
 179 #define SSCOP_ESTABLISH_CNF     STKCMD(SAP_SSCOP, STKCMD_UP, 19)
 180 #define SSCOP_RELEASE_REQ       STKCMD(SAP_SSCOP, STKCMD_DOWN, 20)
 181 #define SSCOP_RELEASE_IND       STKCMD(SAP_SSCOP, STKCMD_UP, 21)
 182 #define SSCOP_RELEASE_CNF       STKCMD(SAP_SSCOP, STKCMD_UP, 22)
 183 #define SSCOP_DATA_REQ          STKCMD(SAP_SSCOP, STKCMD_DOWN, 23)
 184 #define SSCOP_DATA_IND          STKCMD(SAP_SSCOP, STKCMD_UP, 24)
 185 #define SSCOP_RESYNC_REQ        STKCMD(SAP_SSCOP, STKCMD_DOWN, 25)
 186 #define SSCOP_RESYNC_IND        STKCMD(SAP_SSCOP, STKCMD_UP, 26)
 187 #define SSCOP_RESYNC_RSP        STKCMD(SAP_SSCOP, STKCMD_DOWN, 27)
 188 #define SSCOP_RESYNC_CNF        STKCMD(SAP_SSCOP, STKCMD_UP, 28)
 189 #define SSCOP_RECOVER_IND       STKCMD(SAP_SSCOP, STKCMD_UP, 29)
 190 #define SSCOP_RECOVER_RSP       STKCMD(SAP_SSCOP, STKCMD_DOWN, 30)
 191 #define SSCOP_UNITDATA_REQ      STKCMD(SAP_SSCOP, STKCMD_DOWN, 31)
 192 #define SSCOP_UNITDATA_IND      STKCMD(SAP_SSCOP, STKCMD_UP, 32)
 193 #define SSCOP_RETRIEVE_REQ      STKCMD(SAP_SSCOP, STKCMD_DOWN, 33)
 194 #define SSCOP_RETRIEVE_IND      STKCMD(SAP_SSCOP, STKCMD_UP, 34)
 195 #define SSCOP_RETRIEVECMP_IND   STKCMD(SAP_SSCOP, STKCMD_UP, 35)
 196
 197 /* SAP_SSCF_UNI */
 198 #define SSCF_UNI_INIT           STKCMD(SAP_SSCF_UNI, STKCMD_DOWN, CCV_INIT)
 199 #define SSCF_UNI_TERM           STKCMD(SAP_SSCF_UNI, STKCMD_DOWN, CCV_TERM)
 200 #define SSCF_UNI_ESTABLISH_REQ  STKCMD(SAP_SSCF_UNI, STKCMD_DOWN, 16)
 201 #define SSCF_UNI_ESTABLISH_IND  STKCMD(SAP_SSCF_UNI, STKCMD_UP, 17)
 202 #define SSCF_UNI_ESTABLISH_CNF  STKCMD(SAP_SSCF_UNI, STKCMD_UP, 18)
 203 #define SSCF_UNI_RELEASE_REQ    STKCMD(SAP_SSCF_UNI, STKCMD_DOWN, 19)
 204 #define SSCF_UNI_RELEASE_IND    STKCMD(SAP_SSCF_UNI, STKCMD_UP, 20)
 205 #define SSCF_UNI_RELEASE_CNF    STKCMD(SAP_SSCF_UNI, STKCMD_UP, 21)
 206 #define SSCF_UNI_DATA_REQ       STKCMD(SAP_SSCF_UNI, STKCMD_DOWN, 22)
 207 #define SSCF_UNI_DATA_IND       STKCMD(SAP_SSCF_UNI, STKCMD_UP, 23)
 208 #define SSCF_UNI_UNITDATA_REQ   STKCMD(SAP_SSCF_UNI, STKCMD_DOWN, 24)
 209 #define SSCF_UNI_UNITDATA_IND   STKCMD(SAP_SSCF_UNI, STKCMD_UP, 25)
 210
 211
 212 /*
 213  * The STACK_CALL macro must be used for all stack calls between adjacent
 214  * entities.  In order to avoid the problem with recursive stack calls
 215  * modifying protocol state, this macro will only allow calls to proceed if
 216  * they are not "against the flow" of any currently pending calls for a
 217  * stack instance.  If the requested call can't be processed now, it will
 218  * be deferred and queued until a later, safe time (but before control is
 219  * returned back to the kernel scheduler) when it will be dispatched.
 220  *
 221  * The STACK_CALL macro arguments are:
 222  *      cmd = command code;
 223  *      fn  = Destination entity processing function
 224  *      tok = Destination layer's session token;
 225  *      cvp = Connection VCC address;
 226  *      a1  = command specific argument;
 227  *      a2  = command specific argument;
 228  *      ret = call result value (0 => success)
 229  *
 230  * The receiving entity command processing function prototype is:
 231  *
 232  *      void (fn)(int cmd, int tok, int arg1, int arg2)
 233  *
 234  */
 235 #define STACK_CALL(cmd, fn, tok, cvp, a1, a2, ret)                      \
 236 {                                                                       \
 237         if ((cmd) & STKCMD_UP) {                                        \
 238                 if ((cvp)->cvc_downcnt) {                               \
 239                         (ret) = atm_stack_enq((cmd), (fn), (tok),       \
 240                                                 (cvp), (a1), (a2));     \
 241                 } else {                                                \
 242                         (cvp)->cvc_upcnt++;                             \
 243                         (*fn)(cmd, tok, a1, a2);                        \
 244                         (cvp)->cvc_upcnt--;                             \
 245                         (ret) = 0;                                      \
 246                 }                                                       \
 247         } else {                                                        \
 248                 if ((cvp)->cvc_upcnt) {                                 \
 249                         (ret) = atm_stack_enq((cmd), (fn), (tok),       \
 250                                                 (cvp), (a1), (a2));     \
 251                 } else {                                                \
 252                         (cvp)->cvc_downcnt++;                           \
 253                         (*fn)(cmd, tok, a1, a2);                        \
 254                         (cvp)->cvc_downcnt--;                           \
 255                         (ret) = 0;                                      \
 256                 }                                                       \
 257         }                                                               \
 258 }
 259
 260
 261 /*
 262  * Stack queue entry - The stack queue will contain stack calls which have
 263  * been deferred in order to avoid recursive calls to a single protocol
 264  * control block.  The queue entries are allocated from its own storage pool.
 265  */
 266 struct stackq_entry {
 267         struct stackq_entry *sq_next;   /* Next entry in queue */
 268         int             sq_cmd;         /* Stack command */
 269         void            (*sq_func)      /* Destination function */
 270                                 (int, void *, int, int);
 271         void            *sq_token;      /* Destination token */
 272         int             sq_arg1;        /* Command-specific argument */
 273         int             sq_arg2;        /* Command-specific argument */
 274         Atm_connvc      *sq_connvc;     /* Connection VCC */
 275 };
 276
 277
 278 /*
 279  * Macro to avoid unnecessary function call when draining the stack queue.
 280  */
 281 #define STACK_DRAIN()                                                   \
 282 {                                                                       \
 283         if (atm_stackq_head)                                            \
 284                 atm_stack_drain();                                      \
 285 }
 286 #endif  /* ATM_KERNEL */
 287
 288 #endif  /* _NETATM_ATM_STACK_H */