* Greatly reduce the complexity of the LWKT messaging and port abstraction.

[dfdiff.git] / sys / netproto / atm / atm_subr.c

/*
 *
 * ===================================
 * HARP  |  Host ATM Research Platform
 * ===================================
 *
 *
 * This Host ATM Research Platform ("HARP") file (the "Software") is
 * made available by Network Computing Services, Inc. ("NetworkCS")
 * "AS IS".  NetworkCS does not provide maintenance, improvements or
 * support of any kind.
 *
 * NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
 * INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
 * SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
 * In no event shall NetworkCS be responsible for any damages, including
 * but not limited to consequential damages, arising from or relating to
 * any use of the Software or related support.
 *
 * Copyright 1994-1998 Network Computing Services, Inc.
 *
 * Copies of this Software may be made, however, the above copyright
 * notice must be reproduced on all copies.
 *
 *      @(#) $FreeBSD: src/sys/netatm/atm_subr.c,v 1.7 2000/02/13 03:31:59 peter Exp $
 *      @(#) $DragonFly: src/sys/netproto/atm/atm_subr.c,v 1.21 2007/05/23 08:57:07 dillon Exp $
 */

/*
 * Core ATM Services
 * -----------------
 *
 * Miscellaneous ATM subroutines
 *
 */

#include "kern_include.h"

#include <sys/thread2.h>
#include <sys/msgport2.h>

/*
 * Global variables
 */
struct atm_pif          *atm_interface_head = NULL;
struct atm_ncm          *atm_netconv_head = NULL;
Atm_endpoint            *atm_endpoints[ENDPT_MAX+1] = {NULL};
struct sp_info          *atm_pool_head = NULL;
struct stackq_entry     *atm_stackq_head = NULL, *atm_stackq_tail;
struct atm_sock_stat    atm_sock_stat = { { 0 } };
int                     atm_init = 0;
int                     atm_debug = 0;
int                     atm_dev_print = 0;
int                     atm_print_data = 0;
int                     atm_version = ATM_VERSION;
struct timeval          atm_debugtime = {0, 0};
struct ifqueue          atm_intrq;

struct sp_info  atm_attributes_pool = {
        "atm attributes pool",          /* si_name */
        sizeof(Atm_attributes),         /* si_blksiz */
        10,                             /* si_blkcnt */
        100                             /* si_maxallow */
};

static struct callout atm_timexp_ch;

/*
 * Local functions
 */
static void     atm_compact (struct atm_time *);
static KTimeout_ret     atm_timexp (void *);
static void     atm_intr(struct netmsg *);

/*
 * Local variables
 */
static struct atm_time  *atm_timeq = NULL;
static struct atm_time  atm_compactimer = {0, 0};

static struct sp_info   atm_stackq_pool = {
        "Service stack queue pool",     /* si_name */
        sizeof(struct stackq_entry),    /* si_blksiz */
        10,                             /* si_blkcnt */
        10                              /* si_maxallow */
};


/*
 * Initialize ATM kernel
 * 
 * Performs any initialization required before things really get underway.
 * Called from ATM domain initialization or from first registration function 
 * which gets called.
 *
 * Arguments:
 *      none
 *
 * Returns:
 *      none
 *
 */
void
atm_initialize(void)
{
        /*
         * Never called from interrupts, so no locking needed
         */
        if (atm_init)
                return;
        atm_init = 1;

        atm_intrq.ifq_maxlen = ATM_INTRQ_MAX;
        netisr_register(NETISR_ATM, cpu0_portfn, atm_intr);

        /*
         * Initialize subsystems
         */
        atm_aal5_init();

        /*
         * Prime the timer
         */
        callout_init(&atm_timexp_ch);
        callout_reset(&atm_timexp_ch, hz / ATM_HZ, atm_timexp, NULL);

        /*
         * Start the compaction timer
         */
        atm_timeout(&atm_compactimer, SPOOL_COMPACT, atm_compact);
}


/*
 * Allocate a Control Block
 * 
 * Gets a new control block allocated from the specified storage pool, 
 * acquiring memory for new pool chunks if required.  The returned control
 * block's contents will be cleared.
 *
 * Arguments:
 *      sip     pointer to sp_info for storage pool
 *
 * Returns:
 *      addr    pointer to allocated control block
 *      0       allocation failed
 *
 */
void *
atm_allocate(struct sp_info *sip)
{
        void            *bp;
        struct sp_chunk *scp;
        struct sp_link  *slp;

        crit_enter();

        /*
         * Count calls
         */
        sip->si_allocs++;

        /*
         * Are there any free in the pool?
         */
        if (sip->si_free) {

                /*
                 * Find first chunk with a free block
                 */
                for (scp = sip->si_poolh; scp; scp = scp->sc_next) {
                        if (scp->sc_freeh != NULL)
                                break;
                }

        } else {

                /*
                 * No free blocks - have to allocate a new
                 * chunk (but put a limit to this)
                 */
                struct sp_link  *slp_next;
                int     i;

                /*
                 * First time for this pool??
                 */
                if (sip->si_chunksiz == 0) {
                        size_t  n;

                        /*
                         * Initialize pool information
                         */
                        n = sizeof(struct sp_chunk) +
                                sip->si_blkcnt * 
                                (sip->si_blksiz + sizeof(struct sp_link));
                        sip->si_chunksiz = roundup(n, SPOOL_ROUNDUP);

                        /*
                         * Place pool on kernel chain
                         */
                        LINK2TAIL(sip, struct sp_info, atm_pool_head, si_next);
                }

                if (sip->si_chunks >= sip->si_maxallow) {
                        sip->si_fails++;
                        crit_exit();
                        return (NULL);
                }

                scp = KM_ALLOC(sip->si_chunksiz, M_DEVBUF,
                                M_INTWAIT | M_NULLOK);
                if (scp == NULL) {
                        sip->si_fails++;
                        crit_exit();
                        return (NULL);
                }
                scp->sc_next = NULL;
                scp->sc_info = sip;
                scp->sc_magic = SPOOL_MAGIC;
                scp->sc_used = 0;

                /*
                 * Divy up chunk into free blocks
                 */
                slp = (struct sp_link *)(scp + 1);
                scp->sc_freeh = slp;

                for (i = sip->si_blkcnt; i > 1; i--) { 
                        slp_next = (struct sp_link *)((caddr_t)(slp + 1) + 
                                        sip->si_blksiz);
                        slp->sl_u.slu_next = slp_next;
                        slp = slp_next;
                }
                slp->sl_u.slu_next = NULL;
                scp->sc_freet = slp;

                /*
                 * Add new chunk to end of pool
                 */
                if (sip->si_poolh)
                        sip->si_poolt->sc_next = scp;
                else
                        sip->si_poolh = scp;
                sip->si_poolt = scp;
                
                sip->si_chunks++;
                sip->si_total += sip->si_blkcnt;
                sip->si_free += sip->si_blkcnt;
                if (sip->si_chunks > sip->si_maxused)
                        sip->si_maxused = sip->si_chunks;
        }

        /*
         * Allocate the first free block in chunk
         */
        slp = scp->sc_freeh;
        scp->sc_freeh = slp->sl_u.slu_next;
        scp->sc_used++;
        sip->si_free--;
        bp = (slp + 1);

        /*
         * Save link back to pool chunk
         */
        slp->sl_u.slu_chunk = scp;

        /*
         * Clear out block
         */
        KM_ZERO(bp, sip->si_blksiz);

        crit_exit();
        return (bp);
}


/*
 * Free a Control Block
 * 
 * Returns a previously allocated control block back to the owners 
 * storage pool.  
 *
 * Arguments:
 *      bp      pointer to block to be freed
 *
 * Returns:
 *      none
 *
 */
void
atm_free(void *bp)
{
        struct sp_info  *sip;
        struct sp_chunk *scp;
        struct sp_link  *slp;

        crit_enter();

        /*
         * Get containing chunk and pool info
         */
        slp = (struct sp_link *)bp;
        slp--;
        scp = slp->sl_u.slu_chunk;
        if (scp->sc_magic != SPOOL_MAGIC)
                panic("atm_free: chunk magic missing");
        sip = scp->sc_info;

        /*
         * Add block to free chain
         */
        if (scp->sc_freeh) {
                scp->sc_freet->sl_u.slu_next = slp;
                scp->sc_freet = slp;
        } else
                scp->sc_freeh = scp->sc_freet = slp;
        slp->sl_u.slu_next = NULL;
        sip->si_free++;
        scp->sc_used--;

        crit_exit();
        return;
}


/*
 * Storage Pool Compaction
 * 
 * Called periodically in order to perform compaction of the
 * storage pools.  Each pool will be checked to see if any chunks 
 * can be freed, taking some care to avoid freeing too many chunks
 * in order to avoid memory thrashing.
 *
 * Called from a critical section.
 *
 * Arguments:
 *      tip     pointer to timer control block (atm_compactimer)
 *
 * Returns:
 *      none
 *
 */
static void
atm_compact(struct atm_time *tip)
{
        struct sp_info  *sip;
        struct sp_chunk *scp;
        int             i;
        struct sp_chunk *scp_prev;

        /*
         * Check out all storage pools
         */
        for (sip = atm_pool_head; sip; sip = sip->si_next) {

                /*
                 * Always keep a minimum number of chunks around
                 */
                if (sip->si_chunks <= SPOOL_MIN_CHUNK)
                        continue;

                /*
                 * Maximum chunks to free at one time will leave
                 * pool with at least 50% utilization, but never
                 * go below minimum chunk count.
                 */
                i = ((sip->si_free * 2) - sip->si_total) / sip->si_blkcnt;
                i = MIN(i, sip->si_chunks - SPOOL_MIN_CHUNK);

                /*
                 * Look for chunks to free
                 */
                scp_prev = NULL;
                for (scp = sip->si_poolh; scp && i > 0; ) {

                        if (scp->sc_used == 0) {

                                /*
                                 * Found a chunk to free, so do it
                                 */
                                if (scp_prev) {
                                        scp_prev->sc_next = scp->sc_next;
                                        if (sip->si_poolt == scp)
                                                sip->si_poolt = scp_prev;
                                } else
                                        sip->si_poolh = scp->sc_next;

                                KM_FREE((caddr_t)scp, sip->si_chunksiz,
                                        M_DEVBUF);

                                /*
                                 * Update pool controls
                                 */
                                sip->si_chunks--;
                                sip->si_total -= sip->si_blkcnt;
                                sip->si_free -= sip->si_blkcnt;
                                i--;
                                if (scp_prev)
                                        scp = scp_prev->sc_next;
                                else
                                        scp = sip->si_poolh;
                        } else {
                                scp_prev = scp;
                                scp = scp->sc_next;
                        }
                }
        }

        /*
         * Restart the compaction timer
         */
        atm_timeout(&atm_compactimer, SPOOL_COMPACT, atm_compact);

        return;
}


/*
 * Release a Storage Pool
 * 
 * Frees all dynamic storage acquired for a storage pool.
 * This function is normally called just prior to a module's unloading.
 *
 * Arguments:
 *      sip     pointer to sp_info for storage pool
 *
 * Returns:
 *      none
 *
 */
void
atm_release_pool(struct sp_info *sip)
{
        struct sp_chunk *scp, *scp_next;

        crit_enter();
        /*
         * Free each chunk in pool
         */
        for (scp = sip->si_poolh; scp; scp = scp_next) {

                /*
                 * Check for memory leaks
                 */
                if (scp->sc_used)
                        panic("atm_release_pool: unfreed blocks");

                scp_next = scp->sc_next;

                KM_FREE((caddr_t)scp, sip->si_chunksiz, M_DEVBUF);
        }

        /*
         * Update pool controls
         */
        sip->si_poolh = NULL;
        sip->si_chunks = 0;
        sip->si_total = 0;
        sip->si_free = 0;

        /*
         * Unlink pool from active chain
         */
        sip->si_chunksiz = 0;
        UNLINK(sip, struct sp_info, atm_pool_head, si_next);
        crit_exit();
        return;
}


/*
 * Handle timer tick expiration
 * 
 * Decrement tick count in first block on timer queue.  If there
 * are blocks with expired timers, call their timeout function.
 * This function is called ATM_HZ times per second.
 *
 * Arguments:
 *      arg     argument passed on timeout() call
 *
 * Returns:
 *      none
 *
 */
static KTimeout_ret
atm_timexp(void *arg)
{
        struct atm_time *tip;

        crit_enter();
        /*
         * Decrement tick count
         */
        if (((tip = atm_timeq) == NULL) || (--tip->ti_ticks > 0)) {
                goto restart;
        }

        /*
         * Stack queue should have been drained
         */
#ifdef DIAGNOSTIC
        if (atm_stackq_head != NULL)
                panic("atm_timexp: stack queue not empty");
#endif

        /*
         * Dispatch expired timers
         */
        while (((tip = atm_timeq) != NULL) && (tip->ti_ticks == 0)) {
                void    (*func)(struct atm_time *);

                /*
                 * Remove expired block from queue
                 */
                atm_timeq = tip->ti_next;
                tip->ti_flag &= ~TIF_QUEUED;

                /*
                 * Call timeout handler (with network interrupts locked out)
                 */
                func = tip->ti_func;
                (*func)(tip);

                /*
                 * Drain any deferred calls
                 */
                STACK_DRAIN();
        }

restart:
        /*
         * Restart the timer
         */
        crit_exit();
        callout_reset(&atm_timexp_ch, hz / ATM_HZ, atm_timexp, NULL);
}


/*
 * Schedule a control block timeout
 * 
 * Place the supplied timer control block on the timer queue.  The
 * function (func) will be called in 't' timer ticks with the
 * control block address as its only argument.  There are ATM_HZ
 * timer ticks per second.  The ticks value stored in each block is
 * a delta of the number of ticks from the previous block in the queue.
 * Thus, for each tick interval, only the first block in the queue 
 * needs to have its tick value decremented.
 *
 * Arguments:
 *      tip     pointer to timer control block
 *      t       number of timer ticks until expiration
 *      func    pointer to function to call at expiration 
 *
 * Returns:
 *      none
 *
 */
void
atm_timeout(struct atm_time *tip, int t, void (*func)(struct atm_time *))
{
        struct atm_time *tip1, *tip2;


        /*
         * Check for double queueing error
         */
        if (tip->ti_flag & TIF_QUEUED)
                panic("atm_timeout: double queueing");

        /*
         * Make sure we delay at least a little bit
         */
        if (t <= 0)
                t = 1;

        /*
         * Find out where we belong on the queue
         */
        crit_enter();
        for (tip1 = NULL, tip2 = atm_timeq; tip2 && (tip2->ti_ticks <= t); 
                                            tip1 = tip2, tip2 = tip1->ti_next) {
                t -= tip2->ti_ticks;
        }

        /*
         * Place ourselves on queue and update timer deltas
         */
        if (tip1 == NULL)
                atm_timeq = tip;
        else
                tip1->ti_next = tip;
        tip->ti_next = tip2;

        if (tip2)
                tip2->ti_ticks -= t;
        
        /*
         * Setup timer block
         */
        tip->ti_flag |= TIF_QUEUED;
        tip->ti_ticks = t;
        tip->ti_func = func;

        crit_exit();
        return;
}


/*
 * Cancel a timeout
 * 
 * Remove the supplied timer control block from the timer queue.
 *
 * Arguments:
 *      tip     pointer to timer control block
 *
 * Returns:
 *      0       control block successfully dequeued
 *      1       control block not on timer queue
 *
 */
int
atm_untimeout(struct atm_time *tip)
{
        struct atm_time *tip1, *tip2;

        /*
         * Is control block queued?
         */
        if ((tip->ti_flag & TIF_QUEUED) == 0)
                return(1);

        /*
         * Find control block on the queue
         */
        crit_enter();
        for (tip1 = NULL, tip2 = atm_timeq; tip2 && (tip2 != tip); 
                                            tip1 = tip2, tip2 = tip1->ti_next) {
        }

        if (tip2 == NULL) {
                crit_exit();
                return (1);
        }

        /*
         * Remove block from queue and update timer deltas
         */
        tip2 = tip->ti_next;
        if (tip1 == NULL)
                atm_timeq = tip2;
        else
                tip1->ti_next = tip2;

        if (tip2)
                tip2->ti_ticks += tip->ti_ticks;
        
        /*
         * Reset timer block
         */
        tip->ti_flag &= ~TIF_QUEUED;

        crit_exit();
        return (0);
}


/*
 * Queue a Stack Call 
 * 
 * Queues a stack call which must be deferred to the global stack queue.
 * The call parameters are stored in entries which are allocated from the
 * stack queue storage pool.
 *
 * Arguments:
 *      cmd     stack command
 *      func    destination function
 *      token   destination layer's token
 *      cvp     pointer to  connection vcc
 *      arg1    command argument
 *      arg2    command argument
 *
 * Returns:
 *      0       call queued
 *      errno   call not queued - reason indicated
 *
 */
int
atm_stack_enq(int cmd, void (*func)(int, void *, int, int), void *token,
              Atm_connvc *cvp, int arg1, int arg2)
{
        struct stackq_entry     *sqp;

        crit_enter();

        /*
         * Get a new queue entry for this call
         */
        sqp = (struct stackq_entry *)atm_allocate(&atm_stackq_pool);
        if (sqp == NULL) {
                crit_exit();
                return (ENOMEM);
        }

        /*
         * Fill in new entry
         */
        sqp->sq_next = NULL;
        sqp->sq_cmd = cmd;
        sqp->sq_func = func;
        sqp->sq_token = token;
        sqp->sq_arg1 = arg1;
        sqp->sq_arg2 = arg2;
        sqp->sq_connvc = cvp;

        /*
         * Put new entry at end of queue
         */
        if (atm_stackq_head == NULL)
                atm_stackq_head = sqp;
        else
                atm_stackq_tail->sq_next = sqp;
        atm_stackq_tail = sqp;

        crit_exit();
        return (0);
}


/*
 * Drain the Stack Queue
 * 
 * Dequeues and processes entries from the global stack queue.  
 *
 * Arguments:
 *      none
 *
 * Returns:
 *      none
 *
 */
void
atm_stack_drain(void)
{
        struct stackq_entry     *sqp, *qprev, *qnext;
        int             cnt;

        crit_enter();
        /*
         * Loop thru entire queue until queue is empty
         *      (but panic rather loop forever)
         */
        do {
                cnt = 0;
                qprev = NULL;
                for (sqp = atm_stackq_head; sqp; ) {

                        /*
                         * Got an eligible entry, do STACK_CALL stuff
                         */
                        if (sqp->sq_cmd & STKCMD_UP) {
                                if (sqp->sq_connvc->cvc_downcnt) {

                                        /*
                                         * Cant process now, skip it
                                         */
                                        qprev = sqp;
                                        sqp = sqp->sq_next;
                                        continue;
                                }

                                /*
                                 * OK, dispatch the call
                                 */
                                sqp->sq_connvc->cvc_upcnt++;
                                (*sqp->sq_func)(sqp->sq_cmd, 
                                                sqp->sq_token,
                                                sqp->sq_arg1,
                                                sqp->sq_arg2);
                                sqp->sq_connvc->cvc_upcnt--;
                        } else {
                                if (sqp->sq_connvc->cvc_upcnt) {

                                        /*
                                         * Cant process now, skip it
                                         */
                                        qprev = sqp;
                                        sqp = sqp->sq_next;
                                        continue;
                                }

                                /*
                                 * OK, dispatch the call
                                 */
                                sqp->sq_connvc->cvc_downcnt++;
                                (*sqp->sq_func)(sqp->sq_cmd, 
                                                sqp->sq_token,
                                                sqp->sq_arg1,
                                                sqp->sq_arg2);
                                sqp->sq_connvc->cvc_downcnt--;
                        }

                        /*
                         * Dequeue processed entry and free it
                         */
                        cnt++;
                        qnext = sqp->sq_next;
                        if (qprev)
                                qprev->sq_next = qnext;
                        else
                                atm_stackq_head = qnext;
                        if (qnext == NULL)
                                atm_stackq_tail = qprev;
                        atm_free((caddr_t)sqp);
                        sqp = qnext;
                }
        } while (cnt > 0);

        /*
         * Make sure entire queue was drained
         */
        if (atm_stackq_head != NULL)
                panic("atm_stack_drain: Queue not emptied");
        crit_exit();
}


/*
 * Process Interrupt Queue
 * 
 * Processes entries on the ATM interrupt queue.  This queue is used by
 * device interface drivers in order to schedule events from the driver's 
 * lower (interrupt) half to the driver's stack services.
 *
 * The interrupt routines must store the stack processing function to call
 * and a token (typically a driver/stack control block) at the front of the
 * queued buffer.  We assume that the function pointer and token values are 
 * both contained (and properly aligned) in the first buffer of the chain.
 *
 * Arguments:
 *      none
 *
 * Returns:
 *      none
 *
 */
static void
atm_intr(struct netmsg *msg)
{
        struct mbuf *m = ((struct netmsg_packet *)msg)->nm_packet;
        caddr_t         cp;
        atm_intr_func_t func;
        void            *token;

        /*
         * Get function to call and token value
         */
        KB_DATASTART(m, cp, caddr_t);
        func = *(atm_intr_func_t *)cp;
        cp += sizeof(func);
        token = *(void **)cp;
        KB_HEADADJ(m, -(sizeof(func) + sizeof(token)));
        if (KB_LEN(m) == 0) {
                KBuffer         *m1;
                KB_UNLINKHEAD(m, m1);
                m = m1;
        }

        /*
         * Call processing function
         */
        (*func)(token, m);

        /*
         * Drain any deferred calls
         */
        STACK_DRAIN();
        /* msg was embedded in the mbuf, do not reply! */
}

/*
 * Print a pdu buffer chain
 * 
 * Arguments:
 *      m       pointer to pdu buffer chain
 *      msg     pointer to message header string
 *
 * Returns:
 *      none
 *
 */
void
atm_pdu_print(KBuffer *m, char *msg)
{
        caddr_t         cp;
        int             i;
        char            c = ' ';

        kprintf("%s:", msg);
        while (m) { 
                KB_DATASTART(m, cp, caddr_t);
                kprintf("%cbfr=%p data=%p len=%d: ",
                        c, m, cp, KB_LEN(m));
                c = '\t';
                if (atm_print_data) {
                        for (i = 0; i < KB_LEN(m); i++) {
                                kprintf("%2x ", (u_char)*cp++);
                        }
                        kprintf("<end_bfr>\n");
                } else {
                        kprintf("\n");
                }
                m = KB_NEXT(m);
        }
}