[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: Nick Piggin <npiggin@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/cassini.c b/drivers/net/cassini.c
index dde631f..6e295fc 100644
--- a/drivers/net/cassini.c
+++ b/drivers/net/cassini.c
@@ -335,6 +335,30 @@
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 @@
{
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
frag++;
get_page(page->buffer);
+ cas_buffer_inc(page);
frag->page = page->buffer;
frag->page_offset = 0;
frag->size = hlen;
@@ -2225,7 +2253,7 @@
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