drivers/net/ethernet/intel/fm10k/fm10k_main.c

Source file repositories/reference/linux-study-clean/drivers/net/ethernet/intel/fm10k/fm10k_main.c

File Facts

System
Linux kernel
Corpus path
drivers/net/ethernet/intel/fm10k/fm10k_main.c
Extension
.c
Size
54369 bytes
Lines
2008
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

module_init(fm10k_init_module);

/**
 * fm10k_exit_module - Driver Exit Cleanup Routine
 *
 * fm10k_exit_module is called just before the driver is removed
 * from memory.
 **/
static void __exit fm10k_exit_module(void)
{
	fm10k_unregister_pci_driver();

	fm10k_dbg_exit();

	/* destroy driver workqueue */
	destroy_workqueue(fm10k_workqueue);
}
module_exit(fm10k_exit_module);

static bool fm10k_alloc_mapped_page(struct fm10k_ring *rx_ring,
				    struct fm10k_rx_buffer *bi)
{
	struct page *page = bi->page;
	dma_addr_t dma;

	/* Only page will be NULL if buffer was consumed */
	if (likely(page))
		return true;

	/* alloc new page for storage */
	page = dev_alloc_page();
	if (unlikely(!page)) {
		rx_ring->rx_stats.alloc_failed++;
		return false;
	}

	/* map page for use */
	dma = dma_map_page(rx_ring->dev, page, 0, PAGE_SIZE, DMA_FROM_DEVICE);

	/* if mapping failed free memory back to system since
	 * there isn't much point in holding memory we can't use
	 */
	if (dma_mapping_error(rx_ring->dev, dma)) {
		__free_page(page);

		rx_ring->rx_stats.alloc_failed++;
		return false;
	}

	bi->dma = dma;
	bi->page = page;
	bi->page_offset = 0;

	return true;
}

/**
 * fm10k_alloc_rx_buffers - Replace used receive buffers
 * @rx_ring: ring to place buffers on
 * @cleaned_count: number of buffers to replace
 **/
void fm10k_alloc_rx_buffers(struct fm10k_ring *rx_ring, u16 cleaned_count)
{
	union fm10k_rx_desc *rx_desc;
	struct fm10k_rx_buffer *bi;
	u16 i = rx_ring->next_to_use;

	/* nothing to do */
	if (!cleaned_count)
		return;

	rx_desc = FM10K_RX_DESC(rx_ring, i);
	bi = &rx_ring->rx_buffer[i];
	i -= rx_ring->count;

	do {
		if (!fm10k_alloc_mapped_page(rx_ring, bi))
			break;

		/* Refresh the desc even if buffer_addrs didn't change
		 * because each write-back erases this info.
		 */
		rx_desc->q.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);

		rx_desc++;
		bi++;
		i++;
		if (unlikely(!i)) {
			rx_desc = FM10K_RX_DESC(rx_ring, 0);
			bi = rx_ring->rx_buffer;

Annotation

Implementation Notes