kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

ARM: 7805/1: mm: change max*pfn to include the physical offset of memory

Browse source 
Most of the kernel code assumes that max*pfn is maximum pfns because
the physical start of memory is expected to be PFN0. Since this
assumption is not true on ARM architectures, the meaning of max*pfn
is number of memory pages. This is done to keep drivers happy which
are making use of of these variable to calculate the dma bounce limit
using dma_mask.

Now since we have a architecture override possibility for DMAable
maximum pfns, lets make meaning of max*pfns as maximum pnfs on ARM
as well.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Santosh Shilimkar 2013-08-01 03:12:01 +01:00 committed by Russell King
parent 8e0cb8a1f6
commit 26ba47b183
2 changed files with 12 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
arch/arm/include/asm/dma-mapping.h
View file

@ -64,6 +64,7 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
{
return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
}
#else
static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
{
@ -86,6 +87,13 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
}
#endif
/* The ARM override for dma_max_pfn() */
static inline unsigned long dma_max_pfn(struct device *dev)
{
return PHYS_PFN_OFFSET + dma_to_pfn(dev, *dev->dma_mask);
}
#define dma_max_pfn(dev) dma_max_pfn(dev)
/*
* DMA errors are defined by all-bits-set in the DMA address.
*/

10
arch/arm/mm/init.c
View file

@ -426,12 +426,10 @@ void __init bootmem_init(void)
* This doesn't seem to be used by the Linux memory manager any
* more, but is used by ll_rw_block. If we can get rid of it, we
* also get rid of some of the stuff above as well.
*
* Note: max_low_pfn and max_pfn reflect the number of _pages_ in
* the system, not the maximum PFN.
*/
max_low_pfn = max_low - PHYS_PFN_OFFSET;
max_pfn = max_high - PHYS_PFN_OFFSET;
min_low_pfn = min;
max_low_pfn = max_low;
max_pfn = max_high;
}
/*
@ -537,7 +535,7 @@ static inline void free_area_high(unsigned long pfn, unsigned long end)
static void __init free_highpages(void)
{
#ifdef CONFIG_HIGHMEM
unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET;
unsigned long max_low = max_low_pfn;
struct memblock_region *mem, *res;
/* set highmem page free */