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s390: remove virt_to_phys implementation

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virt_to_phys on s390 currently uses the LRA instruction to translate
virtual to physical addresses. This creates an unnecessary overhead
and caused trouble with dma debugging code (when called with an
address pointing to a already unmapped page).
Just get rid of s390's implementation and use the one from
asm-generic/io.h .

Note: with this change virt_to_phys will no longer work on vmalloc'ed
addresses.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Sebastian Ott 2013-05-23 11:55:07 +02:00 committed by Martin Schwidefsky
parent b6ed49e0ce
commit 92820a5f99
1 changed files with 0 additions and 22 deletions
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22
arch/s390/include/asm/io.h
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@ -13,28 +13,6 @@
#include <asm/page.h>
#include <asm/pci_io.h>
/*
* Change virtual addresses to physical addresses and vv.
* These are pretty trivial
*/
static inline unsigned long virt_to_phys(volatile void * address)
{
unsigned long real_address;
asm volatile(
" lra %0,0(%1)\n"
" jz 0f\n"
" la %0,0\n"
"0:"
: "=a" (real_address) : "a" (address) : "cc");
return real_address;
}
#define virt_to_phys virt_to_phys
static inline void * phys_to_virt(unsigned long address)
{
return (void *) address;
}
void *xlate_dev_mem_ptr(unsigned long phys);
#define xlate_dev_mem_ptr xlate_dev_mem_ptr
void unxlate_dev_mem_ptr(unsigned long phys, void *addr);