[PATCH v3 6/6] dpaa_eth: fix iova handling for sg frames

From: laurentiu . tudor
Date: Thu May 30 2019 - 10:23:40 EST


From: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>

The driver relies on the no longer valid assumption that dma addresses
(iovas) are identical to physical addressees and uses phys_to_virt() to
make iova -> vaddr conversions. Fix this also for scatter-gather frames
using the iova -> phys conversion function added in the previous patch.
While at it, clean-up a redundant dpaa_bpid2pool() and pass the bp
as parameter.

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>
Acked-by: Madalin Bucur <madalin.bucur@xxxxxxx>
---
.../net/ethernet/freescale/dpaa/dpaa_eth.c | 40 +++++++++++--------
1 file changed, 23 insertions(+), 17 deletions(-)

diff --git a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
index 46194a04617a..7d978a93dffd 100644
--- a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
+++ b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
@@ -1641,14 +1641,17 @@ static struct sk_buff *dpaa_cleanup_tx_fd(const struct dpaa_priv *priv,

if (unlikely(qm_fd_get_format(fd) == qm_fd_sg)) {
nr_frags = skb_shinfo(skb)->nr_frags;
- dma_unmap_single(dev, addr,
- qm_fd_get_offset(fd) + DPAA_SGT_SIZE,
- dma_dir);

/* The sgt buffer has been allocated with netdev_alloc_frag(),
* it's from lowmem.
*/
- sgt = phys_to_virt(addr + qm_fd_get_offset(fd));
+ sgt = phys_to_virt(dpaa_iova_to_phys(priv,
+ addr +
+ qm_fd_get_offset(fd)));
+
+ dma_unmap_single(dev, addr,
+ qm_fd_get_offset(fd) + DPAA_SGT_SIZE,
+ dma_dir);

/* sgt[0] is from lowmem, was dma_map_single()-ed */
dma_unmap_single(dev, qm_sg_addr(&sgt[0]),
@@ -1663,7 +1666,7 @@ static struct sk_buff *dpaa_cleanup_tx_fd(const struct dpaa_priv *priv,
}

/* Free the page frag that we allocated on Tx */
- skb_free_frag(phys_to_virt(addr));
+ skb_free_frag(skbh);
} else {
dma_unmap_single(dev, addr,
skb_tail_pointer(skb) - (u8 *)skbh, dma_dir);
@@ -1724,14 +1727,14 @@ static struct sk_buff *contig_fd_to_skb(const struct dpaa_priv *priv,
* The page fragment holding the S/G Table is recycled here.
*/
static struct sk_buff *sg_fd_to_skb(const struct dpaa_priv *priv,
- const struct qm_fd *fd)
+ const struct qm_fd *fd,
+ struct dpaa_bp *dpaa_bp,
+ void *vaddr)
{
ssize_t fd_off = qm_fd_get_offset(fd);
- dma_addr_t addr = qm_fd_addr(fd);
const struct qm_sg_entry *sgt;
struct page *page, *head_page;
- struct dpaa_bp *dpaa_bp;
- void *vaddr, *sg_vaddr;
+ void *sg_vaddr;
int frag_off, frag_len;
struct sk_buff *skb;
dma_addr_t sg_addr;
@@ -1740,7 +1743,6 @@ static struct sk_buff *sg_fd_to_skb(const struct dpaa_priv *priv,
int *count_ptr;
int i;

- vaddr = phys_to_virt(addr);
WARN_ON(!IS_ALIGNED((unsigned long)vaddr, SMP_CACHE_BYTES));

/* Iterate through the SGT entries and add data buffers to the skb */
@@ -1751,14 +1753,17 @@ static struct sk_buff *sg_fd_to_skb(const struct dpaa_priv *priv,
WARN_ON(qm_sg_entry_is_ext(&sgt[i]));

sg_addr = qm_sg_addr(&sgt[i]);
- sg_vaddr = phys_to_virt(sg_addr);
- WARN_ON(!IS_ALIGNED((unsigned long)sg_vaddr,
- SMP_CACHE_BYTES));

/* We may use multiple Rx pools */
dpaa_bp = dpaa_bpid2pool(sgt[i].bpid);
- if (!dpaa_bp)
+ if (!dpaa_bp) {
+ pr_info("%s: fail to get dpaa_bp for sg bpid %d\n",
+ __func__, sgt[i].bpid);
goto free_buffers;
+ }
+ sg_vaddr = phys_to_virt(dpaa_iova_to_phys(priv, sg_addr));
+ WARN_ON(!IS_ALIGNED((unsigned long)sg_vaddr,
+ SMP_CACHE_BYTES));

count_ptr = this_cpu_ptr(dpaa_bp->percpu_count);
dma_unmap_single(dpaa_bp->dev, sg_addr, dpaa_bp->size,
@@ -1830,10 +1835,11 @@ static struct sk_buff *sg_fd_to_skb(const struct dpaa_priv *priv,
/* free all the SG entries */
for (i = 0; i < DPAA_SGT_MAX_ENTRIES ; i++) {
sg_addr = qm_sg_addr(&sgt[i]);
- sg_vaddr = phys_to_virt(sg_addr);
- skb_free_frag(sg_vaddr);
dpaa_bp = dpaa_bpid2pool(sgt[i].bpid);
if (dpaa_bp) {
+ sg_addr = dpaa_iova_to_phys(priv, sg_addr);
+ sg_vaddr = phys_to_virt(sg_addr);
+ skb_free_frag(sg_vaddr);
count_ptr = this_cpu_ptr(dpaa_bp->percpu_count);
(*count_ptr)--;
}
@@ -2326,7 +2332,7 @@ static enum qman_cb_dqrr_result rx_default_dqrr(struct qman_portal *portal,
if (likely(fd_format == qm_fd_contig))
skb = contig_fd_to_skb(priv, fd, dpaa_bp, vaddr);
else
- skb = sg_fd_to_skb(priv, fd);
+ skb = sg_fd_to_skb(priv, fd, dpaa_bp, vaddr);
if (!skb)
return qman_cb_dqrr_consume;

--
2.17.1