RT-AC56 3.0.0.4.374.37 core

[tomato.git] / release / src-rt-6.x.4708 / shared / bcm_notif.c

/*
 * Implementation of event notification component.
 *
 * Copyright (C) 2012, Broadcom Corporation
 * All Rights Reserved.
 * 
 * This is UNPUBLISHED PROPRIETARY SOURCE CODE of Broadcom Corporation;
 * the contents of this file may not be disclosed to third parties, copied
 * or duplicated in any form, in whole or in part, without the prior
 * written permission of Broadcom Corporation.
 *
 * $Id$
 */

#include <bcm_cfg.h>
#include <typedefs.h>
#include <osl.h>
#include <bcmutils.h>
#include "bcm_notif_priv.h"
#include <bcm_notif_pub.h>
#include <bcm_mpool_pub.h>


#if defined(BCMDBG) || defined(BCMDBG_ERR)
#define NOTIF_ERROR(args)       printf args
#else
#define NOTIF_ERROR(args)
#endif


static void dealloc_module(bcm_notif_module_t *notif_module);


/*
 * bcm_notif_attach()
 *
 * Notifier module attach-time initialization.
 *
 * Parameters:
 *    osh                Operating system handle.
 *    mpm                Memory pool manager handle.
 *    max_notif_servers  Maximum number of supported servers.
 *    max_notif_clients  Maximum number of supported clients.
 * Returns:
 *    Global notifier module object. NULL on error.
 */
bcm_notif_module_t* BCMATTACHFN(bcm_notif_attach)(osl_t *osh,
                                                  bcm_mpm_mgr_h mpm,
                                                  int max_notif_servers,
                                                  int max_notif_clients)
{
        bcm_notif_module_t *notif_module;
        int                ret;

        /* Allocate global notifier module state. */
        if ((notif_module = MALLOC(osh, sizeof(*notif_module))) == NULL) {
                NOTIF_ERROR(("%s: out of mem, malloced %d bytes\n",
                             __FUNCTION__, MALLOCED(osh)));
                goto fail;
        }

        /* Init global notifier module state. */
        memset(notif_module, 0, sizeof(*notif_module));
        notif_module->osh = osh;
        notif_module->mpm = mpm;

        /* Create memory pool for server objects. */
        ret = bcm_mpm_create_prealloc_pool(mpm,
                                           sizeof(struct bcm_notif_list_struct),
                                           max_notif_servers, NULL, 0,
                                           "notif_s", &notif_module->server_mem_pool);
        if (ret != BCME_OK) {
                goto fail;
        }

        /* Create memory pool for client objects. */
        ret = bcm_mpm_create_prealloc_pool(mpm,
                                           sizeof(struct bcm_notif_client_request),
                                           max_notif_clients, NULL, 0,
                                           "notif_c", &notif_module->client_mem_pool);
        if (ret != BCME_OK) {
                goto fail;
        }


        /* Success. */
        return (notif_module);

fail:
        dealloc_module(notif_module);

        return (NULL);
}

/*
 * bcm_notif_detach()
 *
 * Notifier module detach-time deinitialization.
 *
 * Parameters:
 *    notif_module  Global notifier module object.
 * Returns:
 *    Nothing.
 */
void BCMATTACHFN(bcm_notif_detach)(bcm_notif_module_t *notif_module)
{
        dealloc_module(notif_module);
}


/*
 * dealloc_module()
 *
 * Helper function to perform common resource deallocation.
 *
 * Parameters:
 *    notif_module  Global notifier module object.
 * Returns:
 *    Nothing.
 */
static void BCMATTACHFN(dealloc_module)(bcm_notif_module_t *notif_module)
{
        if (notif_module != NULL) {

                if (notif_module->client_mem_pool != NULL) {
                        bcm_mpm_delete_prealloc_pool(notif_module->mpm,
                                                     &notif_module->client_mem_pool);
                }

                if (notif_module->server_mem_pool != NULL) {
                        bcm_mpm_delete_prealloc_pool(notif_module->mpm,
                                                     &notif_module->server_mem_pool);
                }

                MFREE(notif_module->osh, notif_module, sizeof(*notif_module));
        }
}


/*
 * bcm_notif_create_list()
 *
 * Initialize new list. Allocates memory.
 *
 * Parameters:
 *    notif_module  Global notifier module object.
 *    hdlp          Pointer to opaque list handle.
 * Returns:
 *    BCME_OK     Object initialized successfully. May be used.
 *    BCME_NOMEM  Initialization failed due to no memory. Object must not be used
 */
int bcm_notif_create_list(bcm_notif_module_t *notif_module, bcm_notif_h *hdlp)
{
        int result = BCME_OK;

        if ((*hdlp = bcm_mp_alloc(notif_module->server_mem_pool)) == NULL) {
                result = BCME_NOMEM;
        }
        else {
                memset(*hdlp, 0, sizeof(**hdlp));
                (*hdlp)->allow_list_operations = TRUE;
                (*hdlp)->notif_module = notif_module;
        }

        return (result);
}

/*
 * bcm_notif_add_interest()
 *
 * Add an interested client
 *
 * Parameters
 *    hdl        Opaque list handle.
 *    callback   Client callback routine
 *    passthru   Client pass-thru data
 * Returns:
 *    BCME_OK     Client interest added successfully
 *    BCME_NOMEM  Add failed due to no memory.
 *
 */
int bcm_notif_add_interest(bcm_notif_h hdl,
                           bcm_notif_client_callback callback,
                           bcm_notif_client_data passthru)
{
        int result = BCME_OK;
        struct bcm_notif_client_request *new_node = NULL;
        bcm_notif_module_t *notif_module = hdl->notif_module;


        /* Ensure that list operations are not performed within client callbacks. */
        if (!(hdl->allow_list_operations))
                return (BCME_BUSY);


        /* Allocate a new node for the new client interest request */
        if ((new_node = bcm_mp_alloc(notif_module->client_mem_pool)) == NULL) {
                result = BCME_NOMEM;
        }
        else {
                memset(new_node, 0, sizeof(*new_node));

                /* Initialize the new node with the client's information */
                new_node->callback = callback;
                new_node->passthru = passthru;
                /* Insert it at the tail of the linked list */
                if (hdl->tail == NULL) {
                        /* This is now the first node in the list. */
                        new_node->next = new_node;
                        hdl->tail = new_node;
                }
                else {
                        /* This is not the first node in the list. */
                        /* Insert as new tail in circular list. */
                        new_node->next = hdl->tail->next;
                        hdl->tail->next = new_node;
                        hdl->tail = new_node;
                }
        }

        return (result);
}

/*
 * bcm_notif_remove_interest()
 *
 * Remove an interested client. The callback and passthru must be identical to the data
 * supplied during registration.
 *
 * Parameters
 *    hdl        Opaque list handle.
 *    callback   Client callback routine
 *    passthru   Client pass-thru data
 * Returns:
 *    BCME_OK        Client interest added successfully
 *    BCME_NOTFOUND  Could not locate this specific client registration for removal.
 *
 */
int bcm_notif_remove_interest(bcm_notif_h hdl,
                              bcm_notif_client_callback callback,
                              bcm_notif_client_data passthru)
{
        int result = BCME_NOTFOUND;
        struct bcm_notif_client_request * nodep = hdl->tail;
        bcm_notif_module_t *notif_module = hdl->notif_module;

        /* Ensure that list operations are not performed within client callbacks. */
        if (!(hdl->allow_list_operations))
                return (BCME_BUSY);


        if (nodep && nodep == nodep->next) {
                /*
                 * Special case: list with just one node.
                 * If we get a hit, the list becomes empty because we delete the last node.
                 */
                if (nodep->callback == callback && nodep->passthru == passthru) {
                        bcm_mp_free(notif_module->client_mem_pool, nodep);
                        hdl->tail = NULL;
                        result = BCME_OK;
                }
        } else {
                /*
                 * List with 0 or 2+ elements.
                 */
                struct bcm_notif_client_request * prevp;
                while (nodep) {
                        prevp = nodep;
                        nodep = nodep->next;
                        if (nodep->callback == callback && nodep->passthru == passthru) {
                                /*
                                 * If we got a hit at the tail of the list, need to adjust
                                 * the main list "tail" pointer.
                                 */
                                if (hdl->tail == nodep)
                                        hdl->tail = prevp;
                                result = BCME_OK;
                                prevp->next = nodep->next;
                                bcm_mp_free(notif_module->client_mem_pool, nodep);
                                /* Setting nodep to be 0 breaks us out of the loop. */
                                nodep = 0;
                        }
                }
        }

        return (result);
}

/*
 * bcm_notif_signal()
 *
 * Notify all clients on an event list that the event has occured. Invoke their
 * callbacks and provide both the server data and the client passthru data.
 *
 * Parameters
 *    hdl         Opaque list handle.
 *    server_data Server data for the notification
 * Returns:
 *    BCME_OK     Client interest added successfully
 *    BCME_ERROR  General error
 */
int bcm_notif_signal(bcm_notif_h hdl, bcm_notif_server_data data)
{
        int result = BCME_OK;
        struct bcm_notif_client_request * nodep = hdl->tail;

        /* Ensure that list operations are not performed within client callbacks. */
        if (!(hdl->allow_list_operations))
                return (BCME_BUSY);


        if (nodep) {
                struct bcm_notif_client_request * firstp;
                nodep = nodep->next;
                firstp = nodep;

                /* Mark list to prevent against list operations within client callbacks. */
                hdl->allow_list_operations = FALSE;

                do {
                        /* Signal the current client */
                        nodep->callback(nodep->passthru, data);
                        /* Advance to next client registration */
                        nodep = nodep->next;
                } while (nodep != firstp);

                /* Done client callbacks - allow list operations again. */
                hdl->allow_list_operations = TRUE;
        }

        return (result);
}

/*
 * bcm_notif_delete_list()
 *
 * Remove all the nodes and the list itself.
 *
 * Parameters
 *    hdlp       Pointer to opaque list handle.
 * Returns:
 *    BCME_OK     Event list successfully deleted.
 *    BCME_ERROR  General error
 */
int bcm_notif_delete_list(bcm_notif_h *hdl)
{
        /* First free all the nodes. */
        struct bcm_notif_client_request * nodep = (*hdl)->tail;
        struct bcm_notif_client_request * prevp;
        bcm_notif_module_t *notif_module = (*hdl)->notif_module;

        /* Ensure that list operations are not performed within client callbacks. */
        if (!((*hdl)->allow_list_operations))
                return (BCME_BUSY);


        while (nodep) {
                prevp = nodep;
                nodep = nodep->next;

                if (prevp == nodep) {
                        /* Deleting the last node. Special case. */
                        bcm_mp_free(notif_module->client_mem_pool, nodep);
                        nodep = prevp = NULL;
                } else {
                        prevp->next = nodep->next;
                        bcm_mp_free(notif_module->client_mem_pool, nodep);
                        nodep = prevp->next;
                }
        }

        /* Free the list itself in addition to the nodes. */
        memset(*hdl, 0, sizeof(**hdl));
        bcm_mp_free(notif_module->server_mem_pool, *hdl);
        *hdl = NULL;

        return (BCME_OK);
}

/*
 * bcm_notif_dump_list()
 *
 * For debugging, display interest list
 *
 * Parameters
 *    hdl        Opaque list handle.
 *    b          Output buffer.
 * Returns:
 *    BCME_OK     Event list successfully dumped.
 *    BCME_ERROR  General error.
 */
int bcm_notif_dump_list(bcm_notif_h hdl, struct bcmstrbuf *b)
{
#if defined(BCMDBG)
        struct bcm_notif_client_request * nodep;

        if (hdl == NULL)
                bcm_bprintf(b, "<uninit list>\n");
        else {
                nodep = hdl->tail;

                bcm_bprintf(b, "List id=0x%p: ", hdl);

                if (nodep == NULL) {
                        bcm_bprintf(b, "(empty)");
                } else {
                        /* List is not empty. Display all data in correct sequence. */
                        struct bcm_notif_client_request * firstp = hdl->tail->next;
                        nodep = nodep->next;
                        do {
                                bcm_bprintf(b, " [0x%p,0x%p]", nodep->callback,
                                          nodep->passthru);
                                nodep = nodep->next;
                        } while (nodep != firstp);
                }
        }

        bcm_bprintf(b, "\n");
#endif   

        return (BCME_OK);
}