[PATCH net-next 1/7] net/faraday: Separate rx page storage from rxdesc

[Joel Stanley]

From: Andrew Jeffery 

The ftgmac100 hardware revision in e.g. the Aspeed AST2500 no longer
reserves all bits in RXDES#2 but instead uses the bottom 16 bits to
store MAC frame metadata. Avoid corruption by shifting struct page
pointers out to their own member in struct ftgmac100.

Signed-off-by: Andrew Jeffery 
Signed-off-by: Joel Stanley 
---
 drivers/net/ethernet/faraday/ftgmac100.c | 25 ++---
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c 
b/drivers/net/ethernet/faraday/ftgmac100.c
index 36361f8bf894..40622567159a 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -60,6 +60,8 @@ struct ftgmac100 {
struct ftgmac100_descs *descs;
dma_addr_t descs_dma_addr;
 
+   struct page *rx_pages[RX_QUEUE_ENTRIES];
+
unsigned int rx_pointer;
unsigned int tx_clean_pointer;
unsigned int tx_pointer;
@@ -341,18 +343,27 @@ static bool ftgmac100_rxdes_ipcs_err(struct 
ftgmac100_rxdes *rxdes)
return rxdes->rxdes1 & cpu_to_le32(FTGMAC100_RXDES1_IP_CHKSUM_ERR);
 }
 
+static inline struct page **ftgmac100_rxdes_page_slot(struct ftgmac100 *priv,
+ struct ftgmac100_rxdes 
*rxdes)
+{
+   return >rx_pages[rxdes - priv->descs->rxdes];
+}
+
 /*
  * rxdes2 is not used by hardware. We use it to keep track of page.
  * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
  */
-static void ftgmac100_rxdes_set_page(struct ftgmac100_rxdes *rxdes, struct 
page *page)
+static void ftgmac100_rxdes_set_page(struct ftgmac100 *priv,
+struct ftgmac100_rxdes *rxdes,
+struct page *page)
 {
-   rxdes->rxdes2 = (unsigned int)page;
+   *ftgmac100_rxdes_page_slot(priv, rxdes) = page;
 }
 
-static struct page *ftgmac100_rxdes_get_page(struct ftgmac100_rxdes *rxdes)
+static struct page *ftgmac100_rxdes_get_page(struct ftgmac100 *priv,
+struct ftgmac100_rxdes *rxdes)
 {
-   return (struct page *)rxdes->rxdes2;
+   return *ftgmac100_rxdes_page_slot(priv, rxdes);
 }
 
 /**
@@ -501,7 +512,7 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int 
*processed)
 
do {
dma_addr_t map = ftgmac100_rxdes_get_dma_addr(rxdes);
-   struct page *page = ftgmac100_rxdes_get_page(rxdes);
+   struct page *page = ftgmac100_rxdes_get_page(priv, rxdes);
unsigned int size;
 
dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
@@ -779,7 +790,7 @@ static int ftgmac100_alloc_rx_page(struct ftgmac100 *priv,
return -ENOMEM;
}
 
-   ftgmac100_rxdes_set_page(rxdes, page);
+   ftgmac100_rxdes_set_page(priv, rxdes, page);
ftgmac100_rxdes_set_dma_addr(rxdes, map);
ftgmac100_rxdes_set_dma_own(rxdes);
return 0;
@@ -791,7 +802,7 @@ static void ftgmac100_free_buffers(struct ftgmac100 *priv)
 
for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
struct ftgmac100_rxdes *rxdes = >descs->rxdes[i];
-   struct page *page = ftgmac100_rxdes_get_page(rxdes);
+   struct page *page = ftgmac100_rxdes_get_page(priv, rxdes);
dma_addr_t map = ftgmac100_rxdes_get_dma_addr(rxdes);
 
if (!page)
-- 
2.9.3

[PATCH net-next 1/7] net/faraday: Separate rx page storage from rxdesc

[Joel Stanley]

From: Andrew Jeffery 

The ftgmac100 hardware revision in e.g. the Aspeed AST2500 no longer
reserves all bits in RXDES#2 but instead uses the bottom 16 bits to
store MAC frame metadata. Avoid corruption by shifting struct page
pointers out to their own member in struct ftgmac100.

Signed-off-by: Andrew Jeffery 
Signed-off-by: Joel Stanley 
---
 drivers/net/ethernet/faraday/ftgmac100.c | 25 ++---
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c 
b/drivers/net/ethernet/faraday/ftgmac100.c
index 36361f8bf894..40622567159a 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -60,6 +60,8 @@ struct ftgmac100 {
struct ftgmac100_descs *descs;
dma_addr_t descs_dma_addr;
 
+   struct page *rx_pages[RX_QUEUE_ENTRIES];
+
unsigned int rx_pointer;
unsigned int tx_clean_pointer;
unsigned int tx_pointer;
@@ -341,18 +343,27 @@ static bool ftgmac100_rxdes_ipcs_err(struct 
ftgmac100_rxdes *rxdes)
return rxdes->rxdes1 & cpu_to_le32(FTGMAC100_RXDES1_IP_CHKSUM_ERR);
 }
 
+static inline struct page **ftgmac100_rxdes_page_slot(struct ftgmac100 *priv,
+ struct ftgmac100_rxdes 
*rxdes)
+{
+   return >rx_pages[rxdes - priv->descs->rxdes];
+}
+
 /*
  * rxdes2 is not used by hardware. We use it to keep track of page.
  * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
  */
-static void ftgmac100_rxdes_set_page(struct ftgmac100_rxdes *rxdes, struct 
page *page)
+static void ftgmac100_rxdes_set_page(struct ftgmac100 *priv,
+struct ftgmac100_rxdes *rxdes,
+struct page *page)
 {
-   rxdes->rxdes2 = (unsigned int)page;
+   *ftgmac100_rxdes_page_slot(priv, rxdes) = page;
 }
 
-static struct page *ftgmac100_rxdes_get_page(struct ftgmac100_rxdes *rxdes)
+static struct page *ftgmac100_rxdes_get_page(struct ftgmac100 *priv,
+struct ftgmac100_rxdes *rxdes)
 {
-   return (struct page *)rxdes->rxdes2;
+   return *ftgmac100_rxdes_page_slot(priv, rxdes);
 }
 
 /**
@@ -501,7 +512,7 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int 
*processed)
 
do {
dma_addr_t map = ftgmac100_rxdes_get_dma_addr(rxdes);
-   struct page *page = ftgmac100_rxdes_get_page(rxdes);
+   struct page *page = ftgmac100_rxdes_get_page(priv, rxdes);
unsigned int size;
 
dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
@@ -779,7 +790,7 @@ static int ftgmac100_alloc_rx_page(struct ftgmac100 *priv,
return -ENOMEM;
}
 
-   ftgmac100_rxdes_set_page(rxdes, page);
+   ftgmac100_rxdes_set_page(priv, rxdes, page);
ftgmac100_rxdes_set_dma_addr(rxdes, map);
ftgmac100_rxdes_set_dma_own(rxdes);
return 0;
@@ -791,7 +802,7 @@ static void ftgmac100_free_buffers(struct ftgmac100 *priv)
 
for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
struct ftgmac100_rxdes *rxdes = >descs->rxdes[i];
-   struct page *page = ftgmac100_rxdes_get_page(rxdes);
+   struct page *page = ftgmac100_rxdes_get_page(priv, rxdes);
dma_addr_t map = ftgmac100_rxdes_get_dma_addr(rxdes);
 
if (!page)
-- 
2.9.3