DMA-API.txt: add dma_sync_single/sg API description
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From: David Miller on 3 Feb 2010 22:30 From: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> Date: Thu, 4 Feb 2010 12:13:22 +0900 > This adds the description of the following eight function: > > dma_sync_single_for_cpu > pci_dma_sync_single_for_cpuvoid ^^^^ That "void" is probably some cut and paste error :-) > dma_sync_single_for_device > pci_dma_sync_single_for_device > dma_sync_sg_for_cpu > pci_dma_sync_sg_for_cpu > dma_sync_sg_for_device > pci_dma_sync_sg_for_device > > It was unclear that the API permits a partial sync (some network > drivers already do though). I made it clear that the sync_single API > can do a partial sync but the sync_sg API can't. > > We could do a partial sync with the sync_sg too, however, it's > difficult for driver writers to correctly use the sync_sg API for a > partial sync since the scatterlists passed in to the mapping API can > be modified. It's unlikely that driver writers want to do a partial > sync with the sync_sg API (because the sync_sg API are usually used > for block drivers). So I think that it's better to forbid a partial > sync with the sync_sg API. > > Signed-off-by: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> Acked-by: David S. Miller <davem(a)davemloft.net> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: James Bottomley on 3 Feb 2010 22:40 On Thu, 2010-02-04 at 12:31 +0900, FUJITA Tomonori wrote: > On Wed, 03 Feb 2010 19:21:23 -0800 (PST) > David Miller <davem(a)davemloft.net> wrote: > > > From: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> > > Date: Thu, 4 Feb 2010 12:13:22 +0900 > > > > > This adds the description of the following eight function: > > > > > > dma_sync_single_for_cpu > > > pci_dma_sync_single_for_cpuvoid > > ^^^^ > > > > That "void" is probably some cut and paste error :-) > > Oops. > > > > > dma_sync_single_for_device > > > pci_dma_sync_single_for_device > > > dma_sync_sg_for_cpu > > > pci_dma_sync_sg_for_cpu > > > dma_sync_sg_for_device > > > pci_dma_sync_sg_for_device > > > > > > It was unclear that the API permits a partial sync (some network > > > drivers already do though). I made it clear that the sync_single API > > > can do a partial sync but the sync_sg API can't. > > > > > > We could do a partial sync with the sync_sg too, however, it's > > > difficult for driver writers to correctly use the sync_sg API for a > > > partial sync since the scatterlists passed in to the mapping API can > > > be modified. It's unlikely that driver writers want to do a partial > > > sync with the sync_sg API (because the sync_sg API are usually used > > > for block drivers). So I think that it's better to forbid a partial > > > sync with the sync_sg API. > > > > > > Signed-off-by: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> > > > > Acked-by: David S. Miller <davem(a)davemloft.net> > > Thanks, > > I found other two typos in the commit log so here's the update. > > = > From: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> > Subject: [PATCH -mm 1/4] DMA-API.txt: add dma_sync_single/sg API description > > This adds the description of the following eight function: > > dma_sync_single_for_cpu > pci_dma_sync_single_for_cpu > dma_sync_single_for_device > pci_dma_sync_single_for_device > dma_sync_sg_for_cpu > pci_dma_sync_sg_for_cpu > dma_sync_sg_for_device > pci_dma_sync_sg_for_device > > It was unclear that the API permits a partial sync (some network > drivers already do though). I made it clear that the sync_single API > can do a partial sync but the sync_sg API can't. > > We could do a partial sync with the sync_sg API too, however, it's > difficult for driver writers to correctly use the sync_sg API for a > partial sync since the scatterlists passed in to the mapping API can't > be modified. It's unlikely that driver writers want to do a partial > sync with the sync_sg API (because the sync_sg API are usually used > for block drivers). So I think that it's better to forbid a partial > sync with the sync_sg API. > > Signed-off-by: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> > Acked-by: David S. Miller <davem(a)davemloft.net> > Cc: James Bottomley <James.Bottomley(a)suse.de> For what it's worth, you can add my acked by to both patches too. James -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: FUJITA Tomonori on 3 Feb 2010 22:40
On Wed, 03 Feb 2010 19:21:23 -0800 (PST) David Miller <davem(a)davemloft.net> wrote: > From: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> > Date: Thu, 4 Feb 2010 12:13:22 +0900 > > > This adds the description of the following eight function: > > > > dma_sync_single_for_cpu > > pci_dma_sync_single_for_cpuvoid > ^^^^ > > That "void" is probably some cut and paste error :-) Oops. > > dma_sync_single_for_device > > pci_dma_sync_single_for_device > > dma_sync_sg_for_cpu > > pci_dma_sync_sg_for_cpu > > dma_sync_sg_for_device > > pci_dma_sync_sg_for_device > > > > It was unclear that the API permits a partial sync (some network > > drivers already do though). I made it clear that the sync_single API > > can do a partial sync but the sync_sg API can't. > > > > We could do a partial sync with the sync_sg too, however, it's > > difficult for driver writers to correctly use the sync_sg API for a > > partial sync since the scatterlists passed in to the mapping API can > > be modified. It's unlikely that driver writers want to do a partial > > sync with the sync_sg API (because the sync_sg API are usually used > > for block drivers). So I think that it's better to forbid a partial > > sync with the sync_sg API. > > > > Signed-off-by: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> > > Acked-by: David S. Miller <davem(a)davemloft.net> Thanks, I found other two typos in the commit log so here's the update. = From: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> Subject: [PATCH -mm 1/4] DMA-API.txt: add dma_sync_single/sg API description This adds the description of the following eight function: dma_sync_single_for_cpu pci_dma_sync_single_for_cpu dma_sync_single_for_device pci_dma_sync_single_for_device dma_sync_sg_for_cpu pci_dma_sync_sg_for_cpu dma_sync_sg_for_device pci_dma_sync_sg_for_device It was unclear that the API permits a partial sync (some network drivers already do though). I made it clear that the sync_single API can do a partial sync but the sync_sg API can't. We could do a partial sync with the sync_sg API too, however, it's difficult for driver writers to correctly use the sync_sg API for a partial sync since the scatterlists passed in to the mapping API can't be modified. It's unlikely that driver writers want to do a partial sync with the sync_sg API (because the sync_sg API are usually used for block drivers). So I think that it's better to forbid a partial sync with the sync_sg API. Signed-off-by: FUJITA Tomonori <fujita.tomonori(a)lab.ntt.co.jp> Acked-by: David S. Miller <davem(a)davemloft.net> Cc: James Bottomley <James.Bottomley(a)suse.de> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |