Re: Question: how to map SCSI data DMA address to virtual address?

On Thu, 2006-03-02 at 17:09 +0000, Christoph Hellwig wrote:
> For each sg list entry do something like:
> 
> 	buffer = kmap_atomic(sg->page, KM_USER0) + sg->offset;
> 	<access buffer>
> 	kunmap_atomic(buffer - sg->offset, KM_USER0);

Remember too that the data might not necessarily be valid without a
flush depending on where it has come from (or where it is going).  See
the dma_sync_sg_for_device/cpu.

James


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

---

• References:
  • Question: how to map SCSI data DMA address to virtual address?
    • From: "Ju, Seokmann" <[email protected]>
  • Re: Question: how to map SCSI data DMA address to virtual address?
    • From: Christoph Hellwig <[email protected]>

• Prev by Date: RE: Question: how to map SCSI data DMA address to virtual address?
• Next by Date: Re: [PATCH] Proc: move proc fs hooks from cpuset.c to proc/fs/base.c
• Previous by thread: Re: Question: how to map SCSI data DMA address to virtual address?
• Next by thread: RE: Question: how to map SCSI data DMA address to virtual address?
• Index(es):
  • Date
  • Thread

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]