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| author | Alexander Duyck | 2012-11-16 22:57:13 +0100 |
|---|---|---|
| committer | H. Peter Anvin | 2012-11-17 01:42:09 +0100 |
| commit | fc8d782677f163dee76427fdd8a92bebd2b50b23 (patch) | |
| tree | c3e228bd6a3c194cb28276bb834582a34a4ff371 /arch/x86/mm | |
| parent | x86: Drop 4 unnecessary calls to __pa_symbol (diff) | |
| download | kernel-qcow2-linux-fc8d782677f163dee76427fdd8a92bebd2b50b23.tar.gz kernel-qcow2-linux-fc8d782677f163dee76427fdd8a92bebd2b50b23.tar.xz kernel-qcow2-linux-fc8d782677f163dee76427fdd8a92bebd2b50b23.zip | |
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 <alexander.h.duyck@intel.com>
Link: http://lkml.kernel.org/r/20121116215640.8521.80483.stgit@ahduyck-cp1.jf.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/init_64.c | 18 | ||||
| -rw-r--r-- | arch/x86/mm/pageattr.c | 8 |
2 files changed, 12 insertions, 14 deletions
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 3baff255adac..0374a10f4fb7 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -770,12 +770,10 @@ void set_kernel_text_ro(void) void mark_rodata_ro(void) { unsigned long start = PFN_ALIGN(_text); - unsigned long rodata_start = - ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK; + unsigned long rodata_start = PFN_ALIGN(__start_rodata); unsigned long end = (unsigned long) &__end_rodata_hpage_align; - unsigned long text_end = PAGE_ALIGN((unsigned long) &__stop___ex_table); - unsigned long rodata_end = PAGE_ALIGN((unsigned long) &__end_rodata); - unsigned long data_start = (unsigned long) &_sdata; + unsigned long text_end = PFN_ALIGN(&__stop___ex_table); + unsigned long rodata_end = PFN_ALIGN(&__end_rodata); printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", (end - start) >> 10); @@ -800,12 +798,12 @@ void mark_rodata_ro(void) #endif free_init_pages("unused kernel memory", - (unsigned long) page_address(virt_to_page(text_end)), - (unsigned long) - page_address(virt_to_page(rodata_start))); + (unsigned long) __va(__pa_symbol(text_end)), + (unsigned long) __va(__pa_symbol(rodata_start))); + free_init_pages("unused kernel memory", - (unsigned long) page_address(virt_to_page(rodata_end)), - (unsigned long) page_address(virt_to_page(data_start))); + (unsigned long) __va(__pa_symbol(rodata_end)), + (unsigned long) __va(__pa_symbol(_sdata))); } #endif 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) |