int compaq_nvram_load()

in hotplug/cpqphp_nvram.c [421:633]

• 151 lines of code
• 33 McCabe index (conditional complexity)

int compaq_nvram_load(void __iomem *rom_start, struct controller *ctrl)
{
	u8 bus, device, function;
	u8 nummem, numpmem, numio, numbus;
	u32 rc;
	u8 *p_byte;
	struct pci_resource *mem_node;
	struct pci_resource *p_mem_node;
	struct pci_resource *io_node;
	struct pci_resource *bus_node;
	struct ev_hrt_ctrl *p_ev_ctrl;
	struct ev_hrt_header *p_EV_header;

	if (!evbuffer_init) {
		/* Read the resource list information in from NVRAM */
		if (load_HRT(rom_start))
			memset(evbuffer, 0, 1024);

		evbuffer_init = 1;
	}

	/* If we saved information in NVRAM, use it now */
	p_EV_header = (struct ev_hrt_header *) evbuffer;

	/* The following code is for systems where version 1.0 of this
	 * driver has been loaded, but doesn't support the hardware.
	 * In that case, the driver would incorrectly store something
	 * in NVRAM.
	 */
	if ((p_EV_header->Version == 2) ||
	    ((p_EV_header->Version == 1) && !ctrl->push_flag)) {
		p_byte = &(p_EV_header->next);

		p_ev_ctrl = (struct ev_hrt_ctrl *) &(p_EV_header->next);

		p_byte += 3;

		if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
			return 2;

		bus = p_ev_ctrl->bus;
		device = p_ev_ctrl->device;
		function = p_ev_ctrl->function;

		while ((bus != ctrl->bus) ||
		       (device != PCI_SLOT(ctrl->pci_dev->devfn)) ||
		       (function != PCI_FUNC(ctrl->pci_dev->devfn))) {
			nummem = p_ev_ctrl->mem_avail;
			numpmem = p_ev_ctrl->p_mem_avail;
			numio = p_ev_ctrl->io_avail;
			numbus = p_ev_ctrl->bus_avail;

			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
				return 2;

			/* Skip forward to the next entry */
			p_byte += (nummem + numpmem + numio + numbus) * 8;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
				return 2;

			p_ev_ctrl = (struct ev_hrt_ctrl *) p_byte;

			p_byte += 3;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
				return 2;

			bus = p_ev_ctrl->bus;
			device = p_ev_ctrl->device;
			function = p_ev_ctrl->function;
		}

		nummem = p_ev_ctrl->mem_avail;
		numpmem = p_ev_ctrl->p_mem_avail;
		numio = p_ev_ctrl->io_avail;
		numbus = p_ev_ctrl->bus_avail;

		p_byte += 4;

		if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
			return 2;

		while (nummem--) {
			mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);

			if (!mem_node)
				break;

			mem_node->base = *(u32 *)p_byte;
			dbg("mem base = %8.8x\n", mem_node->base);
			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
				kfree(mem_node);
				return 2;
			}

			mem_node->length = *(u32 *)p_byte;
			dbg("mem length = %8.8x\n", mem_node->length);
			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
				kfree(mem_node);
				return 2;
			}

			mem_node->next = ctrl->mem_head;
			ctrl->mem_head = mem_node;
		}

		while (numpmem--) {
			p_mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);

			if (!p_mem_node)
				break;

			p_mem_node->base = *(u32 *)p_byte;
			dbg("pre-mem base = %8.8x\n", p_mem_node->base);
			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
				kfree(p_mem_node);
				return 2;
			}

			p_mem_node->length = *(u32 *)p_byte;
			dbg("pre-mem length = %8.8x\n", p_mem_node->length);
			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
				kfree(p_mem_node);
				return 2;
			}

			p_mem_node->next = ctrl->p_mem_head;
			ctrl->p_mem_head = p_mem_node;
		}

		while (numio--) {
			io_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);

			if (!io_node)
				break;

			io_node->base = *(u32 *)p_byte;
			dbg("io base = %8.8x\n", io_node->base);
			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
				kfree(io_node);
				return 2;
			}

			io_node->length = *(u32 *)p_byte;
			dbg("io length = %8.8x\n", io_node->length);
			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
				kfree(io_node);
				return 2;
			}

			io_node->next = ctrl->io_head;
			ctrl->io_head = io_node;
		}

		while (numbus--) {
			bus_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);

			if (!bus_node)
				break;

			bus_node->base = *(u32 *)p_byte;
			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
				kfree(bus_node);
				return 2;
			}

			bus_node->length = *(u32 *)p_byte;
			p_byte += 4;

			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
				kfree(bus_node);
				return 2;
			}

			bus_node->next = ctrl->bus_head;
			ctrl->bus_head = bus_node;
		}

		/* If all of the following fail, we don't have any resources for
		 * hot plug add
		 */
		rc = 1;
		rc &= cpqhp_resource_sort_and_combine(&(ctrl->mem_head));
		rc &= cpqhp_resource_sort_and_combine(&(ctrl->p_mem_head));
		rc &= cpqhp_resource_sort_and_combine(&(ctrl->io_head));
		rc &= cpqhp_resource_sort_and_combine(&(ctrl->bus_head));

		if (rc)
			return(rc);
	} else {
		if ((evbuffer[0] != 0) && (!ctrl->push_flag))
			return 1;
	}

	return 0;
}