Commit fa4f0774 authored by Nick Piggin's avatar Nick Piggin Committed by David S. Miller
Browse files

[CASSINI]: dont touch page_count 



Remove page refcount manipulations from cassini driver by using
another field in struct page. Needed for lockless pagecache.

Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent dbd2915c

drivers/net/cassini.c

+32 −4
Original line number Diff line number Diff line
@@ -335,6 +335,30 @@ static inline void cas_mask_intr(struct cas *cp) 
		cas_disable_irq(cp, i);

}



static inline void cas_buffer_init(cas_page_t *cp)

{

	struct page *page = cp->buffer;

	atomic_set((atomic_t *)&page->lru.next, 1);

}



static inline int cas_buffer_count(cas_page_t *cp)

{

	struct page *page = cp->buffer;

	return atomic_read((atomic_t *)&page->lru.next);

}



static inline void cas_buffer_inc(cas_page_t *cp)

{

	struct page *page = cp->buffer;

	atomic_inc((atomic_t *)&page->lru.next);

}



static inline void cas_buffer_dec(cas_page_t *cp)

{

	struct page *page = cp->buffer;

	atomic_dec((atomic_t *)&page->lru.next);

}



static void cas_enable_irq(struct cas *cp, const int ring)

{

	if (ring == 0) { /* all but TX_DONE */
@@ -472,6 +496,7 @@ static int cas_page_free(struct cas *cp, cas_page_t *page) 
{

	pci_unmap_page(cp->pdev, page->dma_addr, cp->page_size, 

		       PCI_DMA_FROMDEVICE);

	cas_buffer_dec(page);

	__free_pages(page->buffer, cp->page_order);

	kfree(page);

	return 0;
@@ -501,6 +526,7 @@ static cas_page_t *cas_page_alloc(struct cas *cp, const gfp_t flags) 
	page->buffer = alloc_pages(flags, cp->page_order);

	if (!page->buffer)

		goto page_err;

	cas_buffer_init(page);

	page->dma_addr = pci_map_page(cp->pdev, page->buffer, 0,

				      cp->page_size, PCI_DMA_FROMDEVICE);

	return page;
@@ -579,7 +605,7 @@ static void cas_spare_recover(struct cas *cp, const gfp_t flags) 
	list_for_each_safe(elem, tmp, &list) {

		cas_page_t *page = list_entry(elem, cas_page_t, list);



		if (page_count(page->buffer) > 1) 

		if (cas_buffer_count(page) > 1)

			continue;



		list_del(elem);
@@ -1347,7 +1373,7 @@ static inline cas_page_t *cas_page_spare(struct cas *cp, const int index) 
	cas_page_t *page = cp->rx_pages[1][index];

	cas_page_t *new;



	if (page_count(page->buffer) == 1)

	if (cas_buffer_count(page) == 1)

		return page;



	new = cas_page_dequeue(cp);
@@ -1367,7 +1393,7 @@ static cas_page_t *cas_page_swap(struct cas *cp, const int ring, 
	cas_page_t **page1 = cp->rx_pages[1];



	/* swap if buffer is in use */

	if (page_count(page0[index]->buffer) > 1) {

	if (cas_buffer_count(page0[index]) > 1) {

		cas_page_t *new = cas_page_spare(cp, index);

		if (new) {

			page1[index] = page0[index];
@@ -2039,6 +2065,7 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, 
		skb->len      += hlen - swivel;



		get_page(page->buffer);

		cas_buffer_inc(page);

		frag->page = page->buffer;

		frag->page_offset = off;

		frag->size = hlen - swivel;
@@ -2063,6 +2090,7 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, 
			frag++;



			get_page(page->buffer);

			cas_buffer_inc(page);

			frag->page = page->buffer;

			frag->page_offset = 0;

			frag->size = hlen;
@@ -2225,7 +2253,7 @@ static int cas_post_rxds_ringN(struct cas *cp, int ring, int num) 
	released = 0;

	while (entry != last) {

		/* make a new buffer if it's still in use */

		if (page_count(page[entry]->buffer) > 1) {

		if (cas_buffer_count(page[entry]) > 1) {

			cas_page_t *new = cas_page_dequeue(cp);

			if (!new) {

				/* let the timer know that we need to