powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa addresses

Ensure __va is given a physical address below PAGE_OFFSET, and __pa is
given a virtual address above PAGE_OFFSET.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190724084638.24982-4-npiggin@gmail.com
This commit is contained in:
Nicholas Piggin 2019-07-24 18:46:37 +10:00 committed by Michael Ellerman
parent 10c4bd7cd2
commit 4dd7554a64

View File

@ -215,9 +215,19 @@ static inline bool pfn_valid(unsigned long pfn)
/*
* gcc miscompiles (unsigned long)(&static_var) - PAGE_OFFSET
* with -mcmodel=medium, so we use & and | instead of - and + on 64-bit.
* This also results in better code generation.
*/
#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET))
#define __pa(x) ((unsigned long)(x) & 0x0fffffffffffffffUL)
#define __va(x) \
({ \
VIRTUAL_BUG_ON((unsigned long)(x) >= PAGE_OFFSET); \
(void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET); \
})
#define __pa(x) \
({ \
VIRTUAL_BUG_ON((unsigned long)(x) < PAGE_OFFSET); \
(unsigned long)(x) & 0x0fffffffffffffffUL; \
})
#else /* 32-bit, non book E */
#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START))