I am doing a DMA from a card to system memory. The system memory "physical
address" is '0x104000'. I am doing this on x86 with kernel version 2.4.2.
Can this address be the address of a user space buffer?
Regards,
Daljeet.
|--------+----------------------->
| | Ingo Molnar |
| | <[EMAIL PROTECTED]|
| | u> |
| | |
| | 05/30/01 |
| | 11:09 PM |
| | Please |
| | respond to |
| | mingo |
| | |
|--------+----------------------->
>--------------------------------------------------------|
| |
| To: Pete Wyckoff <[EMAIL PROTECTED]> |
| cc: Daljeet Maini/India/IBM@IBMIN, |
| [EMAIL PROTECTED] |
| Subject: Re: pte_page |
>--------------------------------------------------------|
On Wed, 30 May 2001, Pete Wyckoff wrote:
> > __pa(page_address(pte_page(pte))) is the address you want. [or
> > pte_val(*pte) & (PAGE_SIZE-1) on x86 but this is platform-dependent.]
>
> Does this work on x86 non-kmapped highmem user pages too? (i.e. is
> page->virtual valid for every potential user page.)
you are right, the highmem-compatible solution is to use page-mem_map as
the physical page index.
Ingo
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