[PATCH] au1000_eth: stop using virt_to_bus()

From: Arnd Bergmann
Date: Tue Jun 07 2022 - 05:02:23 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

The conversion to the dma-mapping API in linux-2.6.11 was incomplete
and left a virt_to_bus() call around. There have been a number of
fixes for DMA mapping API abuse in this driver, but this one always
slipped through.

Change it to just use the existing dma_addr_t pointer, and make it
use the correct types throughout the driver to make it easier to
understand the virtual vs dma address spaces.

Cc: Manuel Lauss <manuel.lauss@xxxxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/net/ethernet/amd/au1000_eth.c | 22 +++++++++++-----------
drivers/net/ethernet/amd/au1000_eth.h | 4 ++--
2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/amd/au1000_eth.c b/drivers/net/ethernet/amd/au1000_eth.c
index c6f003975621..d5f2c6989221 100644
--- a/drivers/net/ethernet/amd/au1000_eth.c
+++ b/drivers/net/ethernet/amd/au1000_eth.c
@@ -820,7 +820,7 @@ static int au1000_rx(struct net_device *dev)
pr_cont("\n");
}
}
- prxd->buff_stat = (u32)(pDB->dma_addr | RX_DMA_ENABLE);
+ prxd->buff_stat = lower_32_bits(pDB->dma_addr) | RX_DMA_ENABLE;
aup->rx_head = (aup->rx_head + 1) & (NUM_RX_DMA - 1);
wmb(); /* drain writebuffer */

@@ -996,7 +996,7 @@ static netdev_tx_t au1000_tx(struct sk_buff *skb, struct net_device *dev)
ps->tx_packets++;
ps->tx_bytes += ptxd->len;

- ptxd->buff_stat = pDB->dma_addr | TX_DMA_ENABLE;
+ ptxd->buff_stat = lower_32_bits(pDB->dma_addr) | TX_DMA_ENABLE;
wmb(); /* drain writebuffer */
dev_kfree_skb(skb);
aup->tx_head = (aup->tx_head + 1) & (NUM_TX_DMA - 1);
@@ -1131,9 +1131,9 @@ static int au1000_probe(struct platform_device *pdev)
/* Allocate the data buffers
* Snooping works fine with eth on all au1xxx
*/
- aup->vaddr = (u32)dma_alloc_coherent(&pdev->dev, MAX_BUF_SIZE *
- (NUM_TX_BUFFS + NUM_RX_BUFFS),
- &aup->dma_addr, 0);
+ aup->vaddr = dma_alloc_coherent(&pdev->dev, MAX_BUF_SIZE *
+ (NUM_TX_BUFFS + NUM_RX_BUFFS),
+ &aup->dma_addr, 0);
if (!aup->vaddr) {
dev_err(&pdev->dev, "failed to allocate data buffers\n");
err = -ENOMEM;
@@ -1234,8 +1234,8 @@ static int au1000_probe(struct platform_device *pdev)
for (i = 0; i < (NUM_TX_BUFFS+NUM_RX_BUFFS); i++) {
pDB->pnext = pDBfree;
pDBfree = pDB;
- pDB->vaddr = (u32 *)((unsigned)aup->vaddr + MAX_BUF_SIZE*i);
- pDB->dma_addr = (dma_addr_t)virt_to_bus(pDB->vaddr);
+ pDB->vaddr = aup->vaddr + MAX_BUF_SIZE * i;
+ pDB->dma_addr = aup->dma_addr + MAX_BUF_SIZE * i;
pDB++;
}
aup->pDBfree = pDBfree;
@@ -1246,7 +1246,7 @@ static int au1000_probe(struct platform_device *pdev)
if (!pDB)
goto err_out;

- aup->rx_dma_ring[i]->buff_stat = (unsigned)pDB->dma_addr;
+ aup->rx_dma_ring[i]->buff_stat = lower_32_bits(pDB->dma_addr);
aup->rx_db_inuse[i] = pDB;
}

@@ -1255,7 +1255,7 @@ static int au1000_probe(struct platform_device *pdev)
if (!pDB)
goto err_out;

- aup->tx_dma_ring[i]->buff_stat = (unsigned)pDB->dma_addr;
+ aup->tx_dma_ring[i]->buff_stat = lower_32_bits(pDB->dma_addr);
aup->tx_dma_ring[i]->len = 0;
aup->tx_db_inuse[i] = pDB;
}
@@ -1310,7 +1310,7 @@ static int au1000_probe(struct platform_device *pdev)
iounmap(aup->mac);
err_remap1:
dma_free_coherent(&pdev->dev, MAX_BUF_SIZE * (NUM_TX_BUFFS + NUM_RX_BUFFS),
- (void *)aup->vaddr, aup->dma_addr);
+ aup->vaddr, aup->dma_addr);
err_vaddr:
free_netdev(dev);
err_alloc:
@@ -1343,7 +1343,7 @@ static int au1000_remove(struct platform_device *pdev)
au1000_ReleaseDB(aup, aup->tx_db_inuse[i]);

dma_free_coherent(&pdev->dev, MAX_BUF_SIZE * (NUM_TX_BUFFS + NUM_RX_BUFFS),
- (void *)aup->vaddr, aup->dma_addr);
+ aup->vaddr, aup->dma_addr);

iounmap(aup->macdma);
iounmap(aup->mac);
diff --git a/drivers/net/ethernet/amd/au1000_eth.h b/drivers/net/ethernet/amd/au1000_eth.h
index e3a3ed29db61..2489c2f4fd8a 100644
--- a/drivers/net/ethernet/amd/au1000_eth.h
+++ b/drivers/net/ethernet/amd/au1000_eth.h
@@ -106,8 +106,8 @@ struct au1000_private {
struct mac_reg *mac; /* mac registers */
u32 *enable; /* address of MAC Enable Register */
void __iomem *macdma; /* base of MAC DMA port */
- u32 vaddr; /* virtual address of rx/tx buffers */
- dma_addr_t dma_addr; /* dma address of rx/tx buffers */
+ void *vaddr; /* virtual address of rx/tx buffers */
+ dma_addr_t dma_addr; /* dma address of rx/tx buffers */

spinlock_t lock; /* Serialise access to device */

--
2.29.2