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#include "ixl_pf_qmgr.h"

static int      ixl_pf_qmgr_find_free_contiguous_block(struct ixl_pf_qmgr *qmgr, int num);

int
ixl_pf_qmgr_init(struct ixl_pf_qmgr *qmgr, u16 num_queues)
{
        if (num_queues < 1)
                return (EINVAL);

        qmgr->num_queues = num_queues;
        qmgr->qinfo = malloc(num_queues * sizeof(struct ixl_pf_qmgr_qinfo),
            M_IXL, M_ZERO | M_NOWAIT);
        if (qmgr->qinfo == NULL)
                return ENOMEM;

        return (0);
}

int
ixl_pf_qmgr_alloc_contiguous(struct ixl_pf_qmgr *qmgr, u16 num, struct ixl_pf_qtag *qtag)
{
        int i;
        int avail;
        int block_start;
        u16 alloc_size;

        if (qtag == NULL || num < 1)
                return (EINVAL);
        
        /* We have to allocate in power-of-two chunks, so get next power of two */
        alloc_size = (u16)next_power_of_two(num);

        /* Don't try if there aren't enough queues */
        avail = ixl_pf_qmgr_get_num_free(qmgr);
        if (avail < alloc_size)
                return (ENOSPC);

        block_start = ixl_pf_qmgr_find_free_contiguous_block(qmgr, alloc_size);
        if (block_start < 0)
                return (ENOSPC);

        /* Mark queues as allocated */
        for (i = block_start; i < block_start + alloc_size; i++)
                qmgr->qinfo[i].allocated = true;

        bzero(qtag, sizeof(*qtag));
        qtag->qmgr = qmgr;
        qtag->type = IXL_PF_QALLOC_CONTIGUOUS;
        qtag->qidx[0] = block_start;
        qtag->num_allocated = alloc_size;
        qtag->num_active = num;

        return (0);
}

/*
 * NB: indices is u16 because this is the queue index width used in the Add VSI AQ command
 */
int
ixl_pf_qmgr_alloc_scattered(struct ixl_pf_qmgr *qmgr, u16 num, struct ixl_pf_qtag *qtag)
{
        int i;
        int avail, count = 0;
        u16 alloc_size;

        if (qtag == NULL || num < 1 || num > 16)
                return (EINVAL);

        /* We have to allocate in power-of-two chunks, so get next power of two */
        alloc_size = (u16)next_power_of_two(num);

        avail = ixl_pf_qmgr_get_num_free(qmgr);
        if (avail < alloc_size)
                return (ENOSPC);

        bzero(qtag, sizeof(*qtag));
        qtag->qmgr = qmgr;
        qtag->type = IXL_PF_QALLOC_SCATTERED;
        qtag->num_active = num;
        qtag->num_allocated = alloc_size;

        for (i = 0; i < qmgr->num_queues; i++) {
                if (!qmgr->qinfo[i].allocated) {
                        qtag->qidx[count] = i;
                        count++;
                        qmgr->qinfo[i].allocated = true;
                        if (count == alloc_size)
                                return (0);
                }
        }

        // Shouldn't get here
        return (EDOOFUS);
}

int
ixl_pf_qmgr_release(struct ixl_pf_qmgr *qmgr, struct ixl_pf_qtag *qtag)
{
        u16 i, qidx;

        if (qtag == NULL)
                return (EINVAL);

        if (qtag->type == IXL_PF_QALLOC_SCATTERED) {
                for (i = 0; i < qtag->num_allocated; i++) {
                        qidx = qtag->qidx[i];
                        bzero(&qmgr->qinfo[qidx], sizeof(qmgr->qinfo[qidx]));
                }
        } else {
                u16 first_index = qtag->qidx[0];
                for (i = first_index; i < first_index + qtag->num_allocated; i++)
                        bzero(&qmgr->qinfo[i], sizeof(qmgr->qinfo[qidx]));
        }

        qtag->qmgr = NULL;
        return (0);
}

int
ixl_pf_qmgr_get_num_queues(struct ixl_pf_qmgr *qmgr)
{
        return (qmgr->num_queues);
}

/*
 * ERJ: This assumes the info array isn't longer than INT_MAX.
 * This assumption might cause a y3k bug or something, I'm sure.
 */
int
ixl_pf_qmgr_get_num_free(struct ixl_pf_qmgr *qmgr)
{
        int count = 0;

        for (int i = 0; i < qmgr->num_queues; i++) {
                if (!qmgr->qinfo[i].allocated)
                        count++;
        }

        return (count);
}

int
ixl_pf_qmgr_get_first_free(struct ixl_pf_qmgr *qmgr, u16 start)
{
        int i;

        if (start > qmgr->num_queues - 1)
                return (-EINVAL);

        for (i = start; i < qmgr->num_queues; i++) {
                if (qmgr->qinfo[i].allocated)
                        continue;
                else
                        return (i);
        }

        // No free queues
        return (-ENOSPC);
}

void
ixl_pf_qmgr_destroy(struct ixl_pf_qmgr *qmgr)
{
        free(qmgr->qinfo, M_IXL);
        qmgr->qinfo = NULL;
}

void
ixl_pf_qmgr_mark_queue_enabled(struct ixl_pf_qtag *qtag, u16 vsi_qidx, bool tx)
{
        MPASS(qtag != NULL);

        struct ixl_pf_qmgr *qmgr = qtag->qmgr;
        u16 pf_qidx = ixl_pf_qidx_from_vsi_qidx(qtag, vsi_qidx);
        if (tx)
                qmgr->qinfo[pf_qidx].tx_enabled = true;
        else
                qmgr->qinfo[pf_qidx].rx_enabled = true;
}

void
ixl_pf_qmgr_mark_queue_disabled(struct ixl_pf_qtag *qtag, u16 vsi_qidx, bool tx)
{
        MPASS(qtag != NULL);

        struct ixl_pf_qmgr *qmgr = qtag->qmgr;
        u16 pf_qidx = ixl_pf_qidx_from_vsi_qidx(qtag, vsi_qidx);
        if (tx)
                qmgr->qinfo[pf_qidx].tx_enabled = false;
        else
                qmgr->qinfo[pf_qidx].rx_enabled = false;
}

void
ixl_pf_qmgr_mark_queue_configured(struct ixl_pf_qtag *qtag, u16 vsi_qidx, bool tx)
{
        MPASS(qtag != NULL);

        struct ixl_pf_qmgr *qmgr = qtag->qmgr;
        u16 pf_qidx = ixl_pf_qidx_from_vsi_qidx(qtag, vsi_qidx);
        if (tx)
                qmgr->qinfo[pf_qidx].tx_configured = true;
        else
                qmgr->qinfo[pf_qidx].rx_configured = true;
}

bool
ixl_pf_qmgr_is_queue_enabled(struct ixl_pf_qtag *qtag, u16 vsi_qidx, bool tx)
{
        MPASS(qtag != NULL);

        struct ixl_pf_qmgr *qmgr = qtag->qmgr;
        u16 pf_qidx = ixl_pf_qidx_from_vsi_qidx(qtag, vsi_qidx);
        if (tx)
                return (qmgr->qinfo[pf_qidx].tx_enabled);
        else
                return (qmgr->qinfo[pf_qidx].rx_enabled);
}

bool
ixl_pf_qmgr_is_queue_configured(struct ixl_pf_qtag *qtag, u16 vsi_qidx, bool tx)
{
        MPASS(qtag != NULL);

        struct ixl_pf_qmgr *qmgr = qtag->qmgr;
        u16 pf_qidx = ixl_pf_qidx_from_vsi_qidx(qtag, vsi_qidx);
        if (tx)
                return (qmgr->qinfo[pf_qidx].tx_configured);
        else
                return (qmgr->qinfo[pf_qidx].rx_configured);
}

void
ixl_pf_qmgr_clear_queue_flags(struct ixl_pf_qtag *qtag)
{
        MPASS(qtag != NULL);

        struct ixl_pf_qmgr *qmgr = qtag->qmgr;
        for (u16 i = 0; i < qtag->num_allocated; i++) {
                u16 pf_qidx = ixl_pf_qidx_from_vsi_qidx(qtag, i);

                qmgr->qinfo[pf_qidx].tx_configured = 0;
                qmgr->qinfo[pf_qidx].rx_configured = 0;
                qmgr->qinfo[pf_qidx].rx_enabled = 0;
                qmgr->qinfo[pf_qidx].tx_enabled = 0;
        }
}

u16
ixl_pf_qidx_from_vsi_qidx(struct ixl_pf_qtag *qtag, u16 index)
{
        MPASS(index < qtag->num_allocated);

        if (qtag->type == IXL_PF_QALLOC_CONTIGUOUS)
                return qtag->first_qidx + index;
        else
                return qtag->qidx[index];
}

/* Static Functions */

static int
ixl_pf_qmgr_find_free_contiguous_block(struct ixl_pf_qmgr *qmgr, int num)
{
        int i;
        int count = 0;
        bool block_started = false;
        int possible_start;

        for (i = 0; i < qmgr->num_queues; i++) {
                if (!qmgr->qinfo[i].allocated) {
                        if (!block_started) {
                                block_started = true;
                                possible_start = i;
                        }
                        count++;
                        if (count == num)
                                return (possible_start);
                } else { /* this queue is already allocated */
                        block_started = false;
                        count = 0;
                }
        }

        /* Can't find a contiguous block of the requested size */
        return (-1);
}