static void process_ncq_command(AHCIState *s, int port, uint8_t *cmd_fis,
                                uint8_t slot)
{
    AHCIDevice *ad = &s->dev[port];
    IDEState *ide_state = &ad->port.ifs[0];
    NCQFrame *ncq_fis = (NCQFrame*)cmd_fis;
    uint8_t tag = ncq_fis->tag >> 3;
    NCQTransferState *ncq_tfs = &ad->ncq_tfs[tag];
    size_t size;

    g_assert(is_ncq(ncq_fis->command));
    if (ncq_tfs->used) {
        /* error - already in use */
        fprintf(stderr, "%s: tag %d already used\n", __FUNCTION__, tag);
        return;
    }

    ncq_tfs->used = 1;
    ncq_tfs->drive = ad;
    ncq_tfs->slot = slot;
    ncq_tfs->cmdh = &((AHCICmdHdr *)ad->lst)[slot];
    ncq_tfs->cmd = ncq_fis->command;
    ncq_tfs->lba = ((uint64_t)ncq_fis->lba5 << 40) |
                   ((uint64_t)ncq_fis->lba4 << 32) |
                   ((uint64_t)ncq_fis->lba3 << 24) |
                   ((uint64_t)ncq_fis->lba2 << 16) |
                   ((uint64_t)ncq_fis->lba1 << 8) |
                   (uint64_t)ncq_fis->lba0;
    ncq_tfs->tag = tag;

    /* Sanity-check the NCQ packet */
    if (tag != slot) {
        DPRINTF(port, "Warn: NCQ slot (%d) did not match the given tag (%d)\n",
                slot, tag);
    }

    if (ncq_fis->aux0 || ncq_fis->aux1 || ncq_fis->aux2 || ncq_fis->aux3) {
        DPRINTF(port, "Warn: Attempt to use NCQ auxiliary fields.\n");
    }
    if (ncq_fis->prio || ncq_fis->icc) {
        DPRINTF(port, "Warn: Unsupported attempt to use PRIO/ICC fields\n");
    }
    if (ncq_fis->fua & NCQ_FIS_FUA_MASK) {
        DPRINTF(port, "Warn: Unsupported attempt to use Force Unit Access\n");
    }
    if (ncq_fis->tag & NCQ_FIS_RARC_MASK) {
        DPRINTF(port, "Warn: Unsupported attempt to use Rebuild Assist\n");
    }

    ncq_tfs->sector_count = ((ncq_fis->sector_count_high << 8) |
                             ncq_fis->sector_count_low);
    if (!ncq_tfs->sector_count) {
        ncq_tfs->sector_count = 0x10000;
    }
    size = ncq_tfs->sector_count * 512;
    ahci_populate_sglist(ad, &ncq_tfs->sglist, ncq_tfs->cmdh, size, 0);

    if (ncq_tfs->sglist.size < size) {
        error_report("ahci: PRDT length for NCQ command (0x%zx) "
                     "is smaller than the requested size (0x%zx)",
                     ncq_tfs->sglist.size, size);
        ncq_err(ncq_tfs);
        ahci_trigger_irq(ad->hba, ad, PORT_IRQ_OVERFLOW);
        return;
    } else if (ncq_tfs->sglist.size != size) {
        DPRINTF(port, "Warn: PRDTL (0x%zx)"
                " does not match requested size (0x%zx)",
                ncq_tfs->sglist.size, size);
    }

    DPRINTF(port, "NCQ transfer LBA from %"PRId64" to %"PRId64", "
            "drive max %"PRId64"\n",
            ncq_tfs->lba, ncq_tfs->lba + ncq_tfs->sector_count - 1,
            ide_state->nb_sectors - 1);

    execute_ncq_command(ncq_tfs);
}

The product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.