diff options
| author | Alexander Duyck <alexander.h.duyck@intel.com> | 2012-11-16 13:57:13 -0800 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-11-16 16:42:09 -0800 |
| commit | fc8d782677f163dee76427fdd8a92bebd2b50b23 (patch) | |
| tree | c3e228bd6a3c194cb28276bb834582a34a4ff371 /arch/x86/mm/init_64.c | |
| parent | 05a476b6e3795f205806662bf09ab95774266292 (diff) | |
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/init_64.c')
| -rw-r--r-- | arch/x86/mm/init_64.c | 18 |
1 files changed, 8 insertions, 10 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 |