From e3ebadd95cb621e2c7436f3d3646447ac9d5c16d Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 7 May 2007 08:44:24 -0700 Subject: Revert "[PATCH] x86: __pa and __pa_symbol address space separation" This was broken. It adds complexity, for no good reason. Rather than separate __pa() and __pa_symbol(), we should deprecate __pa_symbol(), and preferably __pa() too - and just use "virt_to_phys()" instead, which is more readable and has nicer semantics. However, right now, just undo the separation, and make __pa_symbol() be the exact same as __pa(). That fixes the bugs this patch introduced, and we can do the fairly obvious cleanups later. Do the new __phys_addr() function (which is now the actual workhorse for the unified __pa()/__pa_symbol()) as a real external function, that way all the potential issues with compile/link-time optimizations of constant symbol addresses go away, and we can also, if we choose to, add more sanity-checking of the argument. Cc: Eric W. Biederman Cc: Vivek Goyal Cc: Andi Kleen Cc: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-x86_64/page.h | 18 +++++++----------- include/asm-x86_64/pgtable.h | 4 ++-- 2 files changed, 9 insertions(+), 13 deletions(-) (limited to 'include/asm-x86_64') diff --git a/include/asm-x86_64/page.h b/include/asm-x86_64/page.h index b17fc16ec2eb..4d04e2479569 100644 --- a/include/asm-x86_64/page.h +++ b/include/asm-x86_64/page.h @@ -94,26 +94,22 @@ extern unsigned long phys_base; #define KERNEL_TEXT_SIZE (40*1024*1024) #define KERNEL_TEXT_START 0xffffffff80000000 +#define PAGE_OFFSET __PAGE_OFFSET #ifndef __ASSEMBLY__ #include -#endif /* __ASSEMBLY__ */ +extern unsigned long __phys_addr(unsigned long); -#define PAGE_OFFSET __PAGE_OFFSET +#endif /* __ASSEMBLY__ */ -/* Note: __pa(&symbol_visible_to_c) should be always replaced with __pa_symbol. - Otherwise you risk miscompilation. */ -#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET) -/* __pa_symbol should be used for C visible symbols. - This seems to be the official gcc blessed way to do such arithmetic. */ -#define __pa_symbol(x) \ - ({unsigned long v; \ - asm("" : "=r" (v) : "0" (x)); \ - ((v - __START_KERNEL_map) + phys_base); }) +#define __pa(x) __phys_addr((unsigned long)(x)) +#define __pa_symbol(x) __phys_addr((unsigned long)(x)) #define __va(x) ((void *)((unsigned long)(x)+PAGE_OFFSET)) +#define __boot_va(x) __va(x) +#define __boot_pa(x) __pa(x) #ifdef CONFIG_FLATMEM #define pfn_valid(pfn) ((pfn) < end_pfn) #endif diff --git a/include/asm-x86_64/pgtable.h b/include/asm-x86_64/pgtable.h index 599993f6ba84..da3390faaea6 100644 --- a/include/asm-x86_64/pgtable.h +++ b/include/asm-x86_64/pgtable.h @@ -19,7 +19,7 @@ extern pmd_t level2_kernel_pgt[512]; extern pgd_t init_level4_pgt[]; extern unsigned long __supported_pte_mask; -#define swapper_pg_dir ((pgd_t *)NULL) +#define swapper_pg_dir init_level4_pgt extern void paging_init(void); extern void clear_kernel_mapping(unsigned long addr, unsigned long size); @@ -29,7 +29,7 @@ extern void clear_kernel_mapping(unsigned long addr, unsigned long size); * for zero-mapped memory areas etc.. */ extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)]; -#define ZERO_PAGE(vaddr) (pfn_to_page(__pa_symbol(&empty_zero_page) >> PAGE_SHIFT)) +#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) #endif /* !__ASSEMBLY__ */ -- cgit v1.2.2