[ARM] Fix virtual to physical translation macro corner cases

The current use of these macros works well when the conversion is
entirely linear.  In this case, we can be assured that the following
holds true:

	__va(p + s) - s = __va(p)

However, this is not always the case, especially when there is a
non-linear conversion (eg, when there is a 3.5GB hole in memory.)
In this case, if 's' is the size of the region (eg, PAGE_SIZE) and
'p' is the final page, the above is most definitely not true.

So, we must ensure that __va() and __pa() are only used with valid
kernel direct mapped RAM addresses.  This patch tweaks the code
to achieve this.

Tested-by: Charles Moschel <fred99@carolina.rr.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 310e479309efbfa038b8bbc411ef4a991f942310..f1ef5613ccd43248f07ae5aa91963f5ab2eff503 100644 (file)
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -490,26 +490,30 @@ core_initcall(consistent_init);
  */
 void dma_cache_maint(const void *start, size_t size, int direction)
 {
-       const void *end = start + size;
+       void (*inner_op)(const void *, const void *);
+       void (*outer_op)(unsigned long, unsigned long);
 
-       BUG_ON(!virt_addr_valid(start) || !virt_addr_valid(end - 1));
+       BUG_ON(!virt_addr_valid(start) || !virt_addr_valid(start + size - 1));
 
        switch (direction) {
        case DMA_FROM_DEVICE:           /* invalidate only */
-               dmac_inv_range(start, end);
-               outer_inv_range(__pa(start), __pa(end));
+               inner_op = dmac_inv_range;
+               outer_op = outer_inv_range;
                break;
        case DMA_TO_DEVICE:             /* writeback only */
-               dmac_clean_range(start, end);
-               outer_clean_range(__pa(start), __pa(end));
+               inner_op = dmac_clean_range;
+               outer_op = outer_clean_range;
                break;
        case DMA_BIDIRECTIONAL:         /* writeback and invalidate */
-               dmac_flush_range(start, end);
-               outer_flush_range(__pa(start), __pa(end));
+               inner_op = dmac_flush_range;
+               outer_op = outer_flush_range;
                break;
        default:
                BUG();
        }
+
+       inner_op(start, start + size);
+       outer_op(__pa(start), __pa(start) + size);
 }
 EXPORT_SYMBOL(dma_cache_maint);
 

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 34df4d9d03a6afb6f7a65627bb86d3da56c05cba..80fd3b69ae1f55b22e65382bede227a295c6219f 100644 (file)
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -382,7 +382,7 @@ void __init bootmem_init(void)
        for_each_node(node)
                bootmem_free_node(node, mi);
 
-       high_memory = __va(memend_pfn << PAGE_SHIFT);
+       high_memory = __va((memend_pfn << PAGE_SHIFT) - 1) + 1;
 
        /*
         * This doesn't seem to be used by the Linux memory manager any

diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
index 5358fcc7f61ef8a112834fd839162a438df5ff22..f7457fea6de8e84c5aefe949412845550b1bfa5e 100644 (file)
--- a/arch/arm/mm/mmap.c
+++ b/arch/arm/mm/mmap.c
@@ -124,7 +124,7 @@ int valid_phys_addr_range(unsigned long addr, size_t size)
 {
        if (addr < PHYS_OFFSET)
                return 0;
-       if (addr + size > __pa(high_memory))
+       if (addr + size >= __pa(high_memory - 1))
                return 0;
 
        return 1;