lkml.org 
[lkml]   [2014]   [Sep]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH v2] 3c59x: fix bad split of cpu_to_le32(pci_map_single())
On Thu, Sep 25, 2014 at 03:15:19PM +0000, Sylvain 'ythier' Hitier wrote:
> 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@davemloft.net>
> Cc: Meelis Roos <mroos@linux.ee>
> Cc: Neil Horman <nhorman@tuxdriver.com>
> Signed-off-by: Sylvain "ythier" Hitier <sylvain.hitier@gmail.com>
> ---
> 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
>
> --
> Business is about being busy, not being rich...
> Lived 777 days in a Debian package => http://en.wikipedia.org/wiki/Apt,_Vaucluse
> There's THE room for ideals in this mechanical place!
>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Thanks!
Neil



\
 
 \ /
  Last update: 2014-09-25 18:41    [W:0.044 / U:0.088 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site