From fc8d782677f163dee76427fdd8a92bebd2b50b23 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Fri, 16 Nov 2012 13:57:13 -0800 Subject: x86: Use __pa_symbol instead of __pa on C visible symbols When I made an attempt at separating __pa_symbol and __pa I found that there were a number of cases where __pa was used on an obvious symbol. I also caught one non-obvious case as _brk_start and _brk_end are based on the address of __brk_base which is a C visible symbol. In mark_rodata_ro I was able to reduce the overhead of kernel symbol to virtual memory translation by using a combination of __va(__pa_symbol()) instead of page_address(virt_to_page()). Signed-off-by: Alexander Duyck Link: http://lkml.kernel.org/r/20121116215640.8521.80483.stgit@ahduyck-cp1.jf.intel.com Signed-off-by: H. Peter Anvin --- arch/x86/mm/pageattr.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/x86/mm/pageattr.c') diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index a718e0d23503..40f92f3aea54 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -94,12 +94,12 @@ static inline void split_page_count(int level) { } static inline unsigned long highmap_start_pfn(void) { - return __pa(_text) >> PAGE_SHIFT; + return __pa_symbol(_text) >> PAGE_SHIFT; } static inline unsigned long highmap_end_pfn(void) { - return __pa(roundup(_brk_end, PMD_SIZE)) >> PAGE_SHIFT; + return __pa_symbol(roundup(_brk_end, PMD_SIZE)) >> PAGE_SHIFT; } #endif @@ -276,8 +276,8 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address, * The .rodata section needs to be read-only. Using the pfn * catches all aliases. */ - if (within(pfn, __pa((unsigned long)__start_rodata) >> PAGE_SHIFT, - __pa((unsigned long)__end_rodata) >> PAGE_SHIFT)) + if (within(pfn, __pa_symbol(__start_rodata) >> PAGE_SHIFT, + __pa_symbol(__end_rodata) >> PAGE_SHIFT)) pgprot_val(forbidden) |= _PAGE_RW; #if defined(CONFIG_X86_64) && defined(CONFIG_DEBUG_RODATA) -- cgit v1.2.3 From f3c4fbb68e93b10c781c0cc462a9d80770244da6 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Tue, 22 Jan 2013 13:24:32 -0800 Subject: x86, mm: Use new pagetable helpers in try_preserve_large_page() try_preserve_large_page() can be slightly simplified by using the new page_level_*() helpers. This also moves the 'level' over to the new pg_level enum type. Signed-off-by: Dave Hansen Link: http://lkml.kernel.org/r/20130122212432.14F3D993@kernel.stglabs.ibm.com Signed-off-by: H. Peter Anvin --- arch/x86/mm/pageattr.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) (limited to 'arch/x86/mm/pageattr.c') diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 40f92f3aea54..2a5c9ab710b9 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -396,7 +396,7 @@ try_preserve_large_page(pte_t *kpte, unsigned long address, pte_t new_pte, old_pte, *tmp; pgprot_t old_prot, new_prot, req_prot; int i, do_split = 1; - unsigned int level; + enum pg_level level; if (cpa->force_split) return 1; @@ -412,15 +412,12 @@ try_preserve_large_page(pte_t *kpte, unsigned long address, switch (level) { case PG_LEVEL_2M: - psize = PMD_PAGE_SIZE; - pmask = PMD_PAGE_MASK; - break; #ifdef CONFIG_X86_64 case PG_LEVEL_1G: - psize = PUD_PAGE_SIZE; - pmask = PUD_PAGE_MASK; - break; #endif + psize = page_level_size(level); + pmask = page_level_mask(level); + break; default: do_split = -EINVAL; goto out_unlock; -- cgit v1.2.3 From d765653445129b7c476758040e3079480775f80a Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Tue, 22 Jan 2013 13:24:33 -0800 Subject: x86, mm: Create slow_virt_to_phys() This is necessary because __pa() does not work on some kinds of memory, like vmalloc() or the alloc_remap() areas on 32-bit NUMA systems. We have some functions to do conversions _like_ this in the vmalloc() code (like vmalloc_to_page()), but they do not work on sizes other than 4k pages. We would potentially need to be able to handle all the page sizes that we use for the kernel linear mapping (4k, 2M, 1G). In practice, on 32-bit NUMA systems, the percpu areas get stuck in the alloc_remap() area. Any __pa() call on them will break and basically return garbage. This patch introduces a new function slow_virt_to_phys(), which walks the kernel page tables on x86 and should do precisely the same logical thing as __pa(), but actually work on a wider range of memory. It should work on the normal linear mapping, vmalloc(), kmap(), etc... Signed-off-by: Dave Hansen Link: http://lkml.kernel.org/r/20130122212433.4D1FCA62@kernel.stglabs.ibm.com Acked-by: Rik van Riel Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/pgtable_types.h | 1 + arch/x86/mm/pageattr.c | 31 +++++++++++++++++++++++++++++++ 2 files changed, 32 insertions(+) (limited to 'arch/x86/mm/pageattr.c') diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 6c297e7998cc..9f82690f81ed 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -352,6 +352,7 @@ static inline void update_page_count(int level, unsigned long pages) { } * as a pte too. */ extern pte_t *lookup_address(unsigned long address, unsigned int *level); +extern phys_addr_t slow_virt_to_phys(void *__address); #endif /* !__ASSEMBLY__ */ diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 2a5c9ab710b9..6d13d2a3f825 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -363,6 +363,37 @@ pte_t *lookup_address(unsigned long address, unsigned int *level) } EXPORT_SYMBOL_GPL(lookup_address); +/* + * This is necessary because __pa() does not work on some + * kinds of memory, like vmalloc() or the alloc_remap() + * areas on 32-bit NUMA systems. The percpu areas can + * end up in this kind of memory, for instance. + * + * This could be optimized, but it is only intended to be + * used at inititalization time, and keeping it + * unoptimized should increase the testing coverage for + * the more obscure platforms. + */ +phys_addr_t slow_virt_to_phys(void *__virt_addr) +{ + unsigned long virt_addr = (unsigned long)__virt_addr; + phys_addr_t phys_addr; + unsigned long offset; + enum pg_level level; + unsigned long psize; + unsigned long pmask; + pte_t *pte; + + pte = lookup_address(virt_addr, &level); + BUG_ON(!pte); + psize = page_level_size(level); + pmask = page_level_mask(level); + offset = virt_addr & ~pmask; + phys_addr = pte_pfn(*pte) << PAGE_SHIFT; + return (phys_addr | offset); +} +EXPORT_SYMBOL_GPL(slow_virt_to_phys); + /* * Set the new pmd in all the pgds we know about: */ -- cgit v1.2.3