[PATCH v2] 3c59x: fix bad split of cpu_to_le32(pci_map_single())

From: Sylvain 'ythier' Hitier
Date: Thu Sep 25 2014 - 11:15:33 EST


Hello,

When: 2014-09-24_3@06-16-47 -0400
Who: Neil Horman
What:
> You do probably want to fixup
> the changelog to be a bit more clear as to whats going on here.

Date: Wed Sep 24 09:22:16 2014 +0000

3c59x: fix bad split of cpu_to_le32(pci_map_single())

In commit 6f2b6a3005b2c34c39f207a87667564f64f2f91a,
# 3c59x: Add dma error checking and recovery
the intent is to split out the mapping from the byte-swapping in order to
insert a dma_mapping_error() check.

Kinda this semantic patch:

// See http://coccinelle.lip6.fr/
//
// Beware, grouik-and-dirty!
@@
expression DEV, X, Y, Z;
@@
- cpu_to_le32(pci_map_single(DEV, X, Y, Z))
+ dma_addr_t addr = pci_map_single(DEV, X, Y, Z);
+ if (dma_mapping_error(&DEV->dev, addr))
+ /* snip */;
+ cpu_to_le32(addr)

However, the #else part (of the #if DO_ZEROCOPY test) is changed this way:

- cpu_to_le32(pci_map_single(DEV, X, Y, Z))
+ dma_addr_t addr = cpu_to_le32(pci_map_single(DEV, X, Y, Z));
// ^^^^^^^^^^^
// That mismatches the 3 other changes!
+ if (dma_mapping_error(&DEV->dev, addr))
+ /* snip */;
+ cpu_to_le32(addr)

Let's remove the leftover cpu_to_le32() for coherency.

v2: Better changelog.

Fixes: 6f2b6a3005b2c34c39f207a87667564f64f2f91a
# 3c59x: Add dma error checking and recovery
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Meelis Roos <mroos@xxxxxxxx>
Cc: Neil Horman <nhorman@xxxxxxxxxxxxx>
Signed-off-by: Sylvain "ythier" Hitier <sylvain.hitier@xxxxxxxxx>
---
drivers/net/ethernet/3com/3c59x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/3com/3c59x.c b/drivers/net/ethernet/3com/3c59x.c
index 8ca49f04..0a3108b3 100644
--- a/drivers/net/ethernet/3com/3c59x.c
+++ b/drivers/net/ethernet/3com/3c59x.c
@@ -2214,7 +2214,7 @@ boomerang_start_xmit(struct sk_buff *skb, struct net_device *dev)
}
}
#else
- dma_addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, skb->len, PCI_DMA_TODEVICE));
+ dma_addr = pci_map_single(VORTEX_PCI(vp), skb->data, skb->len, PCI_DMA_TODEVICE);
if (dma_mapping_error(&VORTEX_PCI(vp)->dev, dma_addr))
goto out_dma_err;
vp->tx_ring[entry].addr = cpu_to_le32(dma_addr);

Regards,
Sylvain "ythier" Hitier

--
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Lived 777 days in a Debian package => http://en.wikipedia.org/wiki/Apt,_Vaucluse
There's THE room for ideals in this mechanical place!
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