diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/head_32.S | 34 | ||||
| -rw-r--r-- | arch/x86/kernel/head_64.S | 4 | ||||
| -rw-r--r-- | arch/x86/mm/init_32.c | 84 | ||||
| -rw-r--r-- | arch/x86/mm/init_64.c | 110 | ||||
| -rw-r--r-- | arch/x86/mm/ioremap.c | 19 | ||||
| -rw-r--r-- | arch/x86/mm/pageattr-test.c | 9 | ||||
| -rw-r--r-- | arch/x86/mm/pageattr.c | 459 | ||||
| -rw-r--r-- | arch/x86/mm/pat.c | 132 |
8 files changed, 555 insertions, 296 deletions
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index a7010c3a377..e835b4eea70 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -172,10 +172,6 @@ num_subarch_entries = (. - subarch_entries) / 4 * * Note that the stack is not yet set up! */ -#define PTE_ATTR 0x007 /* PRESENT+RW+USER */ -#define PDE_ATTR 0x067 /* PRESENT+RW+USER+DIRTY+ACCESSED */ -#define PGD_ATTR 0x001 /* PRESENT (no other attributes) */ - default_entry: #ifdef CONFIG_X86_PAE @@ -196,9 +192,9 @@ default_entry: movl $pa(pg0), %edi movl %edi, pa(init_pg_tables_start) movl $pa(swapper_pg_pmd), %edx - movl $PTE_ATTR, %eax + movl $PTE_IDENT_ATTR, %eax 10: - leal PDE_ATTR(%edi),%ecx /* Create PMD entry */ + leal PDE_IDENT_ATTR(%edi),%ecx /* Create PMD entry */ movl %ecx,(%edx) /* Store PMD entry */ /* Upper half already zero */ addl $8,%edx @@ -215,7 +211,7 @@ default_entry: * End condition: we must map up to and including INIT_MAP_BEYOND_END * bytes beyond the end of our own page tables. */ - leal (INIT_MAP_BEYOND_END+PTE_ATTR)(%edi),%ebp + leal (INIT_MAP_BEYOND_END+PTE_IDENT_ATTR)(%edi),%ebp cmpl %ebp,%eax jb 10b 1: @@ -224,7 +220,7 @@ default_entry: movl %eax, pa(max_pfn_mapped) /* Do early initialization of the fixmap area */ - movl $pa(swapper_pg_fixmap)+PDE_ATTR,%eax + movl $pa(swapper_pg_fixmap)+PDE_IDENT_ATTR,%eax movl %eax,pa(swapper_pg_pmd+0x1000*KPMDS-8) #else /* Not PAE */ @@ -233,9 +229,9 @@ page_pde_offset = (__PAGE_OFFSET >> 20); movl $pa(pg0), %edi movl %edi, pa(init_pg_tables_start) movl $pa(swapper_pg_dir), %edx - movl $PTE_ATTR, %eax + movl $PTE_IDENT_ATTR, %eax 10: - leal PDE_ATTR(%edi),%ecx /* Create PDE entry */ + leal PDE_IDENT_ATTR(%edi),%ecx /* Create PDE entry */ movl %ecx,(%edx) /* Store identity PDE entry */ movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */ addl $4,%edx @@ -249,7 +245,7 @@ page_pde_offset = (__PAGE_OFFSET >> 20); * bytes beyond the end of our own page tables; the +0x007 is * the attribute bits */ - leal (INIT_MAP_BEYOND_END+PTE_ATTR)(%edi),%ebp + leal (INIT_MAP_BEYOND_END+PTE_IDENT_ATTR)(%edi),%ebp cmpl %ebp,%eax jb 10b movl %edi,pa(init_pg_tables_end) @@ -257,7 +253,7 @@ page_pde_offset = (__PAGE_OFFSET >> 20); movl %eax, pa(max_pfn_mapped) /* Do early initialization of the fixmap area */ - movl $pa(swapper_pg_fixmap)+PDE_ATTR,%eax + movl $pa(swapper_pg_fixmap)+PDE_IDENT_ATTR,%eax movl %eax,pa(swapper_pg_dir+0xffc) #endif jmp 3f @@ -634,19 +630,19 @@ ENTRY(empty_zero_page) /* Page-aligned for the benefit of paravirt? */ .align PAGE_SIZE_asm ENTRY(swapper_pg_dir) - .long pa(swapper_pg_pmd+PGD_ATTR),0 /* low identity map */ + .long pa(swapper_pg_pmd+PGD_IDENT_ATTR),0 /* low identity map */ # if KPMDS == 3 - .long pa(swapper_pg_pmd+PGD_ATTR),0 - .long pa(swapper_pg_pmd+PGD_ATTR+0x1000),0 - .long pa(swapper_pg_pmd+PGD_ATTR+0x2000),0 + .long pa(swapper_pg_pmd+PGD_IDENT_ATTR),0 + .long pa(swapper_pg_pmd+PGD_IDENT_ATTR+0x1000),0 + .long pa(swapper_pg_pmd+PGD_IDENT_ATTR+0x2000),0 # elif KPMDS == 2 .long 0,0 - .long pa(swapper_pg_pmd+PGD_ATTR),0 - .long pa(swapper_pg_pmd+PGD_ATTR+0x1000),0 + .long pa(swapper_pg_pmd+PGD_IDENT_ATTR),0 + .long pa(swapper_pg_pmd+PGD_IDENT_ATTR+0x1000),0 # elif KPMDS == 1 .long 0,0 .long 0,0 - .long pa(swapper_pg_pmd+PGD_ATTR),0 + .long pa(swapper_pg_pmd+PGD_IDENT_ATTR),0 # else # error "Kernel PMDs should be 1, 2 or 3" # endif diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index db3280afe88..26cfdc1d7c7 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -110,7 +110,7 @@ startup_64: movq %rdi, %rax shrq $PMD_SHIFT, %rax andq $(PTRS_PER_PMD - 1), %rax - leaq __PAGE_KERNEL_LARGE_EXEC(%rdi), %rdx + leaq __PAGE_KERNEL_IDENT_LARGE_EXEC(%rdi), %rdx leaq level2_spare_pgt(%rip), %rbx movq %rdx, 0(%rbx, %rax, 8) ident_complete: @@ -374,7 +374,7 @@ NEXT_PAGE(level2_ident_pgt) /* Since I easily can, map the first 1G. * Don't set NX because code runs from these pages. */ - PMDS(0, __PAGE_KERNEL_LARGE_EXEC, PTRS_PER_PMD) + PMDS(0, __PAGE_KERNEL_IDENT_LARGE_EXEC, PTRS_PER_PMD) NEXT_PAGE(level2_kernel_pgt) /* diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 6b9a9358b33..c3789bb1930 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -195,11 +195,30 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base, pgd_t *pgd; pmd_t *pmd; pte_t *pte; - unsigned pages_2m = 0, pages_4k = 0; + unsigned pages_2m, pages_4k; + int mapping_iter; + + /* + * First iteration will setup identity mapping using large/small pages + * based on use_pse, with other attributes same as set by + * the early code in head_32.S + * + * Second iteration will setup the appropriate attributes (NX, GLOBAL..) + * as desired for the kernel identity mapping. + * + * This two pass mechanism conforms to the TLB app note which says: + * + * "Software should not write to a paging-structure entry in a way + * that would change, for any linear address, both the page size + * and either the page frame or attributes." + */ + mapping_iter = 1; if (!cpu_has_pse) use_pse = 0; +repeat: + pages_2m = pages_4k = 0; pfn = start_pfn; pgd_idx = pgd_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET); pgd = pgd_base + pgd_idx; @@ -225,6 +244,13 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base, if (use_pse) { unsigned int addr2; pgprot_t prot = PAGE_KERNEL_LARGE; + /* + * first pass will use the same initial + * identity mapping attribute + _PAGE_PSE. + */ + pgprot_t init_prot = + __pgprot(PTE_IDENT_ATTR | + _PAGE_PSE); addr2 = (pfn + PTRS_PER_PTE-1) * PAGE_SIZE + PAGE_OFFSET + PAGE_SIZE-1; @@ -234,7 +260,10 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base, prot = PAGE_KERNEL_LARGE_EXEC; pages_2m++; - set_pmd(pmd, pfn_pmd(pfn, prot)); + if (mapping_iter == 1) + set_pmd(pmd, pfn_pmd(pfn, init_prot)); + else + set_pmd(pmd, pfn_pmd(pfn, prot)); pfn += PTRS_PER_PTE; continue; @@ -246,17 +275,43 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base, for (; pte_ofs < PTRS_PER_PTE && pfn < end_pfn; pte++, pfn++, pte_ofs++, addr += PAGE_SIZE) { pgprot_t prot = PAGE_KERNEL; + /* + * first pass will use the same initial + * identity mapping attribute. + */ + pgprot_t init_prot = __pgprot(PTE_IDENT_ATTR); if (is_kernel_text(addr)) prot = PAGE_KERNEL_EXEC; pages_4k++; - set_pte(pte, pfn_pte(pfn, prot)); + if (mapping_iter == 1) + set_pte(pte, pfn_pte(pfn, init_prot)); + else + set_pte(pte, pfn_pte(pfn, prot)); } } } - update_page_count(PG_LEVEL_2M, pages_2m); - update_page_count(PG_LEVEL_4K, pages_4k); + if (mapping_iter == 1) { + /* + * update direct mapping page count only in the first + * iteration. + */ + update_page_count(PG_LEVEL_2M, pages_2m); + update_page_count(PG_LEVEL_4K, pages_4k); + + /* + * local global flush tlb, which will flush the previous + * mappings present in both small and large page TLB's. + */ + __flush_tlb_all(); + + /* + * Second iteration will set the actual desired PTE attributes. + */ + mapping_iter = 2; + goto repeat; + } } /* @@ -719,7 +774,7 @@ void __init setup_bootmem_allocator(void) after_init_bootmem = 1; } -static void __init find_early_table_space(unsigned long end) +static void __init find_early_table_space(unsigned long end, int use_pse) { unsigned long puds, pmds, ptes, tables, start; @@ -729,7 +784,7 @@ static void __init find_early_table_space(unsigned long end) pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; tables += PAGE_ALIGN(pmds * sizeof(pmd_t)); - if (cpu_has_pse) { + if (use_pse) { unsigned long extra; extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT); @@ -769,12 +824,22 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, pgd_t *pgd_base = swapper_pg_dir; unsigned long start_pfn, end_pfn; unsigned long big_page_start; +#ifdef CONFIG_DEBUG_PAGEALLOC + /* + * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages. + * This will simplify cpa(), which otherwise needs to support splitting + * large pages into small in interrupt context, etc. + */ + int use_pse = 0; +#else + int use_pse = cpu_has_pse; +#endif /* * Find space for the kernel direct mapping tables. */ if (!after_init_bootmem) - find_early_table_space(end); + find_early_table_space(end, use_pse); #ifdef CONFIG_X86_PAE set_nx(); @@ -820,7 +885,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); if (start_pfn < end_pfn) kernel_physical_mapping_init(pgd_base, start_pfn, end_pfn, - cpu_has_pse); + use_pse); /* tail is not big page alignment ? */ start_pfn = end_pfn; @@ -983,7 +1048,6 @@ void __init mem_init(void) if (boot_cpu_data.wp_works_ok < 0) test_wp_bit(); - cpa_init(); save_pg_dir(); zap_low_mappings(); } diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 770536ebf7e..fb30486c82f 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -271,7 +271,8 @@ static __ref void unmap_low_page(void *adr) } static unsigned long __meminit -phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end) +phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end, + pgprot_t prot) { unsigned pages = 0; unsigned long last_map_addr = end; @@ -289,36 +290,43 @@ phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end) break; } + /* + * We will re-use the existing mapping. + * Xen for example has some special requirements, like mapping + * pagetable pages as RO. So assume someone who pre-setup + * these mappings are more intelligent. + */ if (pte_val(*pte)) continue; if (0) printk(" pte=%p addr=%lx pte=%016lx\n", pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte); - set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL)); - last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE; pages++; + set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot)); + last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE; } + update_page_count(PG_LEVEL_4K, pages); return last_map_addr; } static unsigned long __meminit -phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end) +phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end, + pgprot_t prot) { pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd); - return phys_pte_init(pte, address, end); + return phys_pte_init(pte, address, end, prot); } static unsigned long __meminit phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, - unsigned long page_size_mask) + unsigned long page_size_mask, pgprot_t prot) { unsigned long pages = 0; unsigned long last_map_addr = end; - unsigned long start = address; int i = pmd_index(address); @@ -326,6 +334,7 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, unsigned long pte_phys; pmd_t *pmd = pmd_page + pmd_index(address); pte_t *pte; + pgprot_t new_prot = prot; if (address >= end) { if (!after_bootmem) { @@ -339,27 +348,40 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, if (!pmd_large(*pmd)) { spin_lock(&init_mm.page_table_lock); last_map_addr = phys_pte_update(pmd, address, - end); + end, prot); spin_unlock(&init_mm.page_table_lock); + continue; } - /* Count entries we're using from level2_ident_pgt */ - if (start == 0) - pages++; - continue; + /* + * If we are ok with PG_LEVEL_2M mapping, then we will + * use the existing mapping, + * + * Otherwise, we will split the large page mapping but + * use the same existing protection bits except for + * large page, so that we don't violate Intel's TLB + * Application note (317080) which says, while changing + * the page sizes, new and old translations should + * not differ with respect to page frame and + * attributes. + */ + if (page_size_mask & (1 << PG_LEVEL_2M)) + continue; + new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd)); } if (page_size_mask & (1<<PG_LEVEL_2M)) { pages++; spin_lock(&init_mm.page_table_lock); set_pte((pte_t *)pmd, - pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE)); + pfn_pte(address >> PAGE_SHIFT, + __pgprot(pgprot_val(prot) | _PAGE_PSE))); spin_unlock(&init_mm.page_table_lock); last_map_addr = (address & PMD_MASK) + PMD_SIZE; continue; } pte = alloc_low_page(&pte_phys); - last_map_addr = phys_pte_init(pte, address, end); + last_map_addr = phys_pte_init(pte, address, end, new_prot); unmap_low_page(pte); spin_lock(&init_mm.page_table_lock); @@ -372,12 +394,12 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, static unsigned long __meminit phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end, - unsigned long page_size_mask) + unsigned long page_size_mask, pgprot_t prot) { pmd_t *pmd = pmd_offset(pud, 0); unsigned long last_map_addr; - last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask); + last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot); __flush_tlb_all(); return last_map_addr; } @@ -394,6 +416,7 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, unsigned long pmd_phys; pud_t *pud = pud_page + pud_index(addr); pmd_t *pmd; + pgprot_t prot = PAGE_KERNEL; if (addr >= end) break; @@ -405,10 +428,26 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, } if (pud_val(*pud)) { - if (!pud_large(*pud)) + if (!pud_large(*pud)) { last_map_addr = phys_pmd_update(pud, addr, end, - page_size_mask); - continue; + page_size_mask, prot); + continue; + } + /* + * If we are ok with PG_LEVEL_1G mapping, then we will + * use the existing mapping. + * + * Otherwise, we will split the gbpage mapping but use + * the same existing protection bits except for large + * page, so that we don't violate Intel's TLB + * Application note (317080) which says, while changing + * the page sizes, new and old translations should + * not differ with respect to page frame and + * attributes. + */ + if (page_size_mask & (1 << PG_LEVEL_1G)) + continue; + prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud)); } if (page_size_mask & (1<<PG_LEVEL_1G)) { @@ -422,7 +461,8 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, } pmd = alloc_low_page(&pmd_phys); - last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask); + last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask, + prot); unmap_low_page(pmd); spin_lock(&init_mm.page_table_lock); @@ -430,6 +470,7 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, spin_unlock(&init_mm.page_table_lock); } __flush_tlb_all(); + update_page_count(PG_LEVEL_1G, pages); return last_map_addr; @@ -446,13 +487,14 @@ phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end, return phys_pud_init(pud, addr, end, page_size_mask); } -static void __init find_early_table_space(unsigned long end) +static void __init find_early_table_space(unsigned long end, int use_pse, + int use_gbpages) { unsigned long puds, pmds, ptes, tables, start; puds = (end + PUD_SIZE - 1) >> PUD_SHIFT; tables = roundup(puds * sizeof(pud_t), PAGE_SIZE); - if (direct_gbpages) { + if (use_gbpages) { unsigned long extra; extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT); pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT; @@ -460,7 +502,7 @@ static void __init find_early_table_space(unsigned long end) pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE); - if (cpu_has_pse) { + if (use_pse) { unsigned long extra; extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT); ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT; @@ -528,6 +570,7 @@ static unsigned long __init kernel_physical_mapping_init(unsigned long start, pgd_populate(&init_mm, pgd, __va(pud_phys)); spin_unlock(&init_mm.page_table_lock); } + __flush_tlb_all(); return last_map_addr; } @@ -571,6 +614,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, struct map_range mr[NR_RANGE_MR]; int nr_range, i; + int use_pse, use_gbpages; printk(KERN_INFO "init_memory_mapping\n"); @@ -584,9 +628,21 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, if (!after_bootmem) init_gbpages(); - if (direct_gbpages) +#ifdef CONFIG_DEBUG_PAGEALLOC + /* + * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages. + * This will simplify cpa(), which otherwise needs to support splitting + * large pages into small in interrupt context, etc. + */ + use_pse = use_gbpages = 0; +#else + use_pse = cpu_has_pse; + use_gbpages = direct_gbpages; +#endif + + if (use_gbpages) page_size_mask |= 1 << PG_LEVEL_1G; - if (cpu_has_pse) + if (use_pse) page_size_mask |= 1 << PG_LEVEL_2M; memset(mr, 0, sizeof(mr)); @@ -647,7 +703,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k")); if (!after_bootmem) - find_early_table_space(end); + find_early_table_space(end, use_pse, use_gbpages); for (i = 0; i < nr_range; i++) last_map_addr = kernel_physical_mapping_init( @@ -806,8 +862,6 @@ void __init mem_init(void) reservedpages << (PAGE_SHIFT-10), datasize >> 10, initsize >> 10); - - cpa_init(); } void free_init_pages(char *what, unsigned long begin, unsigned long end) diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index cac6da54203..6ab3196d12b 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -83,6 +83,25 @@ int page_is_ram(unsigned long pagenr) return 0; } +int pagerange_is_ram(unsigned long start, unsigned long end) +{ + int ram_page = 0, not_rampage = 0; + unsigned long page_nr; + + for (page_nr = (start >> PAGE_SHIFT); page_nr < (end >> PAGE_SHIFT); + ++page_nr) { + if (page_is_ram(page_nr)) + ram_page = 1; + else + not_rampage = 1; + + if (ram_page == not_rampage) + return -1; + } + + return ram_page; +} + /* * Fix up the linear direct mapping of the kernel to avoid cache attribute * conflicts. diff --git a/arch/x86/mm/pageattr-test.c b/arch/x86/mm/pageattr-test.c index d4aa503caaa..e1d10690921 100644 --- a/arch/x86/mm/pageattr-test.c +++ b/arch/x86/mm/pageattr-test.c @@ -32,7 +32,7 @@ enum { GPS = (1<<30) }; -#define PAGE_TESTBIT __pgprot(_PAGE_UNUSED1) +#define PAGE_CPA_TEST __pgprot(_PAGE_CPA_TEST) static int pte_testbit(pte_t pte) { @@ -118,6 +118,7 @@ static int pageattr_test(void) unsigned int level; int i, k; int err; + unsigned long test_addr; if (print) printk(KERN_INFO "CPA self-test:\n"); @@ -172,7 +173,8 @@ static int pageattr_test(void) continue; } - err = change_page_attr_set(addr[i], len[i], PAGE_TESTBIT); + test_addr = addr[i]; + err = change_page_attr_set(&test_addr, len[i], PAGE_CPA_TEST, 0); if (err < 0) { printk(KERN_ERR "CPA %d failed %d\n", i, err); failed++; @@ -204,7 +206,8 @@ static int pageattr_test(void) failed++; continue; } - err = change_page_attr_clear(addr[i], len[i], PAGE_TESTBIT); + test_addr = addr[i]; + err = change_page_attr_clear(&test_addr, len[i], PAGE_CPA_TEST, 0); if (err < 0) { printk(KERN_ERR "CPA reverting failed: %d\n", err); failed++; diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 898fad617ab..a9ec89c3fbc 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -25,15 +25,27 @@ * The current flushing context - we pass it instead of 5 arguments: */ struct cpa_data { - unsigned long vaddr; + unsigned long *vaddr; pgprot_t mask_set; pgprot_t mask_clr; int numpages; - int flushtlb; + int flags; unsigned long pfn; unsigned force_split : 1; + int curpage; }; +/* + * Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings) + * using cpa_lock. So that we don't allow any other cpu, with stale large tlb + * entries change the page attribute in parallel to some other cpu + * splitting a large page entry along with changing the attribute. + */ +static DEFINE_SPINLOCK(cpa_lock); + +#define CPA_FLUSHTLB 1 +#define CPA_ARRAY 2 + #ifdef CONFIG_PROC_FS static unsigned long direct_pages_count[PG_LEVEL_NUM]; @@ -190,6 +202,41 @@ static void cpa_flush_range(unsigned long start, int numpages, int cache) } } +static void cpa_flush_array(unsigned long *start, int numpages, int cache) +{ + unsigned int i, level; + unsigned long *addr; + + BUG_ON(irqs_disabled()); + + on_each_cpu(__cpa_flush_range, NULL, 1); + + if (!cache) + return; + + /* 4M threshold */ + if (numpages >= 1024) { + if (boot_cpu_data.x86_model >= 4) + wbinvd(); + return; + } + /* + * We only need to flush on one CPU, + * clflush is a MESI-coherent instruction that + * will cause all other CPUs to flush the same + * cachelines: + */ + for (i = 0, addr = start; i < numpages; i++, addr++) { + pte_t *pte = lookup_address(*addr, &level); + + /* + * Only flush present addresses: + */ + if (pte && (pte_val(*pte) & _PAGE_PRESENT)) + clflush_cache_range((void *) *addr, PAGE_SIZE); + } +} + /* * Certain areas of memory on x86 require very specific protection flags, * for example the BIOS area or kernel text. Callers don't always get this @@ -398,7 +445,7 @@ try_preserve_large_page(pte_t *kpte, unsigned long address, */ new_pte = pfn_pte(pte_pfn(old_pte), canon_pgprot(new_prot)); __set_pmd_pte(kpte, address, new_pte); - cpa->flushtlb = 1; + cpa->flags |= CPA_FLUSHTLB; do_split = 0; } @@ -408,84 +455,6 @@ out_unlock: return do_split; } -static LIST_HEAD(page_pool); -static unsigned long pool_size, pool_pages, pool_low; -static unsigned long pool_used, pool_failed; - -static void cpa_fill_pool(struct page **ret) -{ - gfp_t gfp = GFP_KERNEL; - unsigned long flags; - struct page *p; - - /* - * Avoid recursion (on debug-pagealloc) and also signal - * our priority to get to these pagetables: - */ - if (current->flags & PF_MEMALLOC) - return; - current->flags |= PF_MEMALLOC; - - /* - * Allocate atomically from atomic contexts: - */ - if (in_atomic() || irqs_disabled() || debug_pagealloc) - gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN; - - while (pool_pages < pool_size || (ret && !*ret)) { - p = alloc_pages(gfp, 0); - if (!p) { - pool_failed++; - break; - } - /* - * If the call site needs a page right now, provide it: - */ - if (ret && !*ret) { - *ret = p; - continue; - } - spin_lock_irqsave(&pgd_lock, flags); - list_add(&p->lru, &page_pool); - pool_pages++; - spin_unlock_irqrestore(&pgd_lock, flags); - } - - current->flags &= ~PF_MEMALLOC; -} - -#define SHIFT_MB (20 - PAGE_SHIFT) -#define ROUND_MB_GB ((1 << 10) - 1) -#define SHIFT_MB_GB 10 -#define POOL_PAGES_PER_GB 16 - -void __init cpa_init(void) -{ - struct sysinfo si; - unsigned long gb; - - si_meminfo(&si); - /* - * Calculate the number of pool pages: - * - * Convert totalram (nr of pages) to MiB and round to the next - * GiB. Shift MiB to Gib and multiply the result by - * POOL_PAGES_PER_GB: - */ - if (debug_pagealloc) { - gb = ((si.totalram >> SHIFT_MB) + ROUND_MB_GB) >> SHIFT_MB_GB; - pool_size = POOL_PAGES_PER_GB * gb; - } else { - pool_size = 1; - } - pool_low = pool_size; - - cpa_fill_pool(NULL); - printk(KERN_DEBUG - "CPA: page pool initialized %lu of %lu pages preallocated\n", - pool_pages, pool_size); -} - static int split_large_page(pte_t *kpte, unsigned long address) { unsigned long flags, pfn, pfninc = 1; @@ -494,28 +463,15 @@ static int split_large_page(pte_t *kpte, unsigned long address) pgprot_t ref_prot; struct page *base; - /* - * Get a page from the pool. The pool list is protected by the - * pgd_lock, which we have to take anyway for the split - * operation: - */ - spin_lock_irqsave(&pgd_lock, flags); - if (list_empty(&page_pool)) { - spin_unlock_irqrestore(&pgd_lock, flags); - base = NULL; - cpa_fill_pool(&base); - if (!base) - return -ENOMEM; - spin_lock_irqsave(&pgd_lock, flags); - } else { - base = list_first_entry(&page_pool, struct page, lru); - list_del(&base->lru); - pool_pages--; - - if (pool_pages < pool_low) - pool_low = pool_pages; - } + if (!debug_pagealloc) + spin_unlock(&cpa_lock); + base = alloc_pages(GFP_KERNEL, 0); + if (!debug_pagealloc) + spin_lock(&cpa_lock); + if (!base) + return -ENOMEM; + spin_lock_irqsave(&pgd_lock, flags); /* * Check for races, another CPU might have split this page * up for us already: @@ -572,11 +528,8 @@ out_unlock: * If we dropped out via the lookup_address check under * pgd_lock then stick the page back into the pool: */ - if (base) { - list_add(&base->lru, &page_pool); - pool_pages++; - } else - pool_used++; + if (base) + __free_page(base); spin_unlock_irqrestore(&pgd_lock, flags); return 0; @@ -584,11 +537,16 @@ out_unlock: static int __change_page_attr(struct cpa_data *cpa, int primary) { - unsigned long address = cpa->vaddr; + unsigned long address; int do_split, err; unsigned int level; pte_t *kpte, old_pte; + if (cpa->flags & CPA_ARRAY) + address = cpa->vaddr[cpa->curpage]; + else + address = *cpa->vaddr; + repeat: kpte = lookup_address(address, &level); if (!kpte) @@ -600,7 +558,7 @@ repeat: return 0; WARN(1, KERN_WARNING "CPA: called for zero pte. " "vaddr = %lx cpa->vaddr = %lx\n", address, - cpa->vaddr); + *cpa->vaddr); return -EINVAL; } @@ -626,7 +584,7 @@ repeat: */ if (pte_val(old_pte) != pte_val(new_pte)) { set_pte_atomic(kpte, new_pte); - cpa->flushtlb = 1; + cpa->flags |= CPA_FLUSHTLB; } cpa->numpages = 1; return 0; @@ -650,7 +608,25 @@ repeat: */ err = split_large_page(kpte, address); if (!err) { - cpa->flushtlb = 1; + /* + * Do a global flush tlb after splitting the large page + * and before we do the actual change page attribute in the PTE. + * + * With out this, we violate the TLB application note, that says + * "The TLBs may contain both ordinary and large-page + * translations for a 4-KByte range of linear addresses. This + * may occur if software modifies the paging structures so that + * the page size used for the address range changes. If the two + * translations differ with respect to page frame or attributes + * (e.g., permissions), processor behavior is undefined and may + * be implementation-specific." + * + * We do this global tlb flush inside the cpa_lock, so that we + * don't allow any other cpu, with stale tlb entries change the + * page attribute in parallel, that also falls into the + * just split large page entry. + */ + flush_tlb_all(); goto repeat; } @@ -663,6 +639,7 @@ static int cpa_process_alias(struct cpa_data *cpa) { struct cpa_data alias_cpa; int ret = 0; + unsigned long temp_cpa_vaddr, vaddr; if (cpa->pfn >= max_pfn_mapped) return 0; @@ -675,16 +652,24 @@ static int cpa_process_alias(struct cpa_data *cpa) * No need to redo, when the primary call touched the direct * mapping already: */ - if (!(within(cpa->vaddr, PAGE_OFFSET, + if (cpa->flags & CPA_ARRAY) + vaddr = cpa->vaddr[cpa->curpage]; + else + vaddr = *cpa->vaddr; + + if (!(within(vaddr, PAGE_OFFSET, PAGE_OFFSET + (max_low_pfn_mapped << PAGE_SHIFT)) #ifdef CONFIG_X86_64 - || within(cpa->vaddr, PAGE_OFFSET + (1UL<<32), + || within(vaddr, PAGE_OFFSET + (1UL<<32), PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)) #endif )) { alias_cpa = *cpa; - alias_cpa.vaddr = (unsigned long) __va(cpa->pfn << PAGE_SHIFT); + temp_cpa_vaddr = (unsigned long) __va(cpa->pfn << PAGE_SHIFT); + alias_cpa.vaddr = &temp_cpa_vaddr; + alias_cpa.flags &= ~CPA_ARRAY; + ret = __change_page_attr_set_clr(&alias_cpa, 0); } @@ -696,7 +681,7 @@ static int cpa_process_alias(struct cpa_data *cpa) * No need to redo, when the primary call touched the high * mapping already: */ - if (within(cpa->vaddr, (unsigned long) _text, (unsigned long) _end)) + if (within(vaddr, (unsigned long) _text, (unsigned long) _end)) return 0; /* @@ -707,8 +692,9 @@ static int cpa_process_alias(struct cpa_data *cpa) return 0; alias_cpa = *cpa; - alias_cpa.vaddr = - (cpa->pfn << PAGE_SHIFT) + __START_KERNEL_map - phys_base; + temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) + __START_KERNEL_map - phys_base; + alias_cpa.vaddr = &temp_cpa_vaddr; + alias_cpa.flags &= ~CPA_ARRAY; /* * The high mapping range is imprecise, so ignore the return value. @@ -728,8 +714,15 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias) * preservation check. */ cpa->numpages = numpages; + /* for array changes, we can't use large page */ + if (cpa->flags & CPA_ARRAY) + cpa->numpages = 1; + if (!debug_pagealloc) + spin_lock(&cpa_lock); ret = __change_page_attr(cpa, checkalias); + if (!debug_pagealloc) + spin_unlock(&cpa_lock); if (ret) return ret; @@ -746,7 +739,11 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias) */ BUG_ON(cpa->numpages > numpages); numpages -= cpa->numpages; - cpa->vaddr += cpa->numpages * PAGE_SIZE; + if (cpa->flags & CPA_ARRAY) + cpa->curpage++; + else + *cpa->vaddr += cpa->numpages * PAGE_SIZE; + } return 0; } @@ -757,9 +754,9 @@ static inline int cache_attr(pgprot_t attr) (_PAGE_PAT | _PAGE_PAT_LARGE | _PAGE_PWT | _PAGE_PCD); } -static int change_page_attr_set_clr(unsigned long addr, int numpages, +static int change_page_attr_set_clr(unsigned long *addr, int numpages, pgprot_t mask_set, pgprot_t mask_clr, - int force_split) + int force_split, int array) { struct cpa_data cpa; int ret, cache, checkalias; @@ -774,21 +771,38 @@ static int change_page_attr_set_clr(unsigned long addr, int numpages, return 0; /* Ensure we are PAGE_SIZE aligned */ - if (addr & ~PAGE_MASK) { - addr &= PAGE_MASK; - /* - * People should not be passing in unaligned addresses: - */ - WARN_ON_ONCE(1); + if (!array) { + if (*addr & ~PAGE_MASK) { + *addr &= PAGE_MASK; + /* + * People should not be passing in unaligned addresses: + */ + WARN_ON_ONCE(1); + } + } else { + int i; + for (i = 0; i < numpages; i++) { + if (addr[i] & ~PAGE_MASK) { + addr[i] &= PAGE_MASK; + WARN_ON_ONCE(1); + } + } } + /* Must avoid aliasing mappings in the highmem code */ + kmap_flush_unused(); + cpa.vaddr = addr; cpa.numpages = numpages; cpa.mask_set = mask_set; cpa.mask_clr = mask_clr; - cpa.flushtlb = 0; + cpa.flags = 0; + cpa.curpage = 0; cpa.force_split = force_split; + if (array) + cpa.flags |= CPA_ARRAY; + /* No alias checking for _NX bit modifications */ checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX; @@ -797,7 +811,7 @@ static int change_page_attr_set_clr(unsigned long addr, int numpages, /* * Check whether we really changed something: */ - if (!cpa.flushtlb) + if (!(cpa.flags & CPA_FLUSHTLB)) goto out; /* @@ -812,27 +826,30 @@ static int change_page_attr_set_clr(unsigned long addr, int numpages, * error case we fall back to cpa_flush_all (which uses * wbindv): */ - if (!ret && cpu_has_clflush) - cpa_flush_range(addr, numpages, cache); - else + if (!ret && cpu_has_clflush) { + if (cpa.flags & CPA_ARRAY) + cpa_flush_array(addr, numpages, cache); + else + cpa_flush_range(*addr, numpages, cache); + } else cpa_flush_all(cache); out: - cpa_fill_pool(NULL); - return ret; } -static inline int change_page_attr_set(unsigned long addr, int numpages, - pgprot_t mask) +static inline int change_page_attr_set(unsigned long *addr, int numpages, + pgprot_t mask, int array) { - return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0); + return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0, + array); } -static inline int change_page_attr_clear(unsigned long addr, int numpages, - pgprot_t mask) +static inline int change_page_attr_clear(unsigned long *addr, int numpages, + pgprot_t mask, int array) { - return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0); + return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0, + array); } int _set_memory_uc(unsigned long addr, int numpages) @@ -840,8 +857,8 @@ int _set_memory_uc(unsigned long addr, int numpages) /* * for now UC MINUS. see comments in ioremap_nocache() */ - return change_page_attr_set(addr, numpages, - __pgprot(_PAGE_CACHE_UC_MINUS)); + return change_page_attr_set(&addr, numpages, + __pgprot(_PAGE_CACHE_UC_MINUS), 0); } int set_memory_uc(unsigned long addr, int numpages) @@ -857,10 +874,48 @@ int set_memory_uc(unsigned long addr, int numpages) } EXPORT_SYMBOL(set_memory_uc); +int set_memory_array_uc(unsigned long *addr, int addrinarray) +{ + unsigned long start; + unsigned long end; + int i; + /* + * for now UC MINUS. see comments in ioremap_nocache() + */ + for (i = 0; i < addrinarray; i++) { + start = __pa(addr[i]); + for (end = start + PAGE_SIZE; i < addrinarray - 1; end += PAGE_SIZE) { + if (end != __pa(addr[i + 1])) + break; + i++; + } + if (reserve_memtype(start, end, _PAGE_CACHE_UC_MINUS, NULL)) + goto out; + } + + return change_page_attr_set(addr, addrinarray, + __pgprot(_PAGE_CACHE_UC_MINUS), 1); +out: + for (i = 0; i < addrinarray; i++) { + unsigned long tmp = __pa(addr[i]); + + if (tmp == start) + break; + for (end = tmp + PAGE_SIZE; i < addrinarray - 1; end += PAGE_SIZE) { + if (end != __pa(addr[i + 1])) + break; + i++; + } + free_memtype(tmp, end); + } + return -EINVAL; +} +EXPORT_SYMBOL(set_memory_array_uc); + int _set_memory_wc(unsigned long addr, int numpages) { - return change_page_attr_set(addr, numpages, - __pgprot(_PAGE_CACHE_WC)); + return change_page_attr_set(&addr, numpages, + __pgprot(_PAGE_CACHE_WC), 0); } int set_memory_wc(unsigned long addr, int numpages) @@ -878,8 +933,8 @@ EXPORT_SYMBOL(set_memory_wc); int _set_memory_wb(unsigned long addr, int numpages) { - return change_page_attr_clear(addr, numpages, - __pgprot(_PAGE_CACHE_MASK)); + return change_page_attr_clear(&addr, numpages, + __pgprot(_PAGE_CACHE_MASK), 0); } int set_memory_wb(unsigned long addr, int numpages) @@ -890,39 +945,59 @@ int set_memory_wb(unsigned long addr, int numpages) } EXPORT_SYMBOL(set_memory_wb); +int set_memory_array_wb(unsigned long *addr, int addrinarray) +{ + int i; + + for (i = 0; i < addrinarray; i++) { + unsigned long start = __pa(addr[i]); + unsigned long end; + + for (end = start + PAGE_SIZE; i < addrinarray - 1; end += PAGE_SIZE) { + if (end != __pa(addr[i + 1])) + break; + i++; + } + free_memtype(start, end); + } + return change_page_attr_clear(addr, addrinarray, + __pgprot(_PAGE_CACHE_MASK), 1); +} +EXPORT_SYMBOL(set_memory_array_wb); + int set_memory_x(unsigned long addr, int numpages) { - return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_NX)); + return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_NX), 0); } EXPORT_SYMBOL(set_memory_x); int set_memory_nx(unsigned long addr, int numpages) { - return change_page_attr_set(addr, numpages, __pgprot(_PAGE_NX)); + return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_NX), 0); } EXPORT_SYMBOL(set_memory_nx); int set_memory_ro(unsigned long addr, int numpages) { - return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_RW)); + return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0); } EXPORT_SYMBOL_GPL(set_memory_ro); int set_memory_rw(unsigned long addr, int numpages) { - return change_page_attr_set(addr, numpages, __pgprot(_PAGE_RW)); + return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0); } EXPORT_SYMBOL_GPL(set_memory_rw); int set_memory_np(unsigned long addr, int numpages) { - return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_PRESENT)); + return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_PRESENT), 0); } int set_memory_4k(unsigned long addr, int numpages) { - return change_page_attr_set_clr(addr, numpages, __pgprot(0), - __pgprot(0), 1); + return change_page_attr_set_clr(&addr, numpages, __pgprot(0), + __pgprot(0), 1, 0); } int set_pages_uc(struct page *page, int numpages) @@ -975,22 +1050,38 @@ int set_pages_rw(struct page *page, int numpages) static int __set_pages_p(struct page *page, int numpages) { - struct cpa_data cpa = { .vaddr = (unsigned long) page_address(page), + unsigned long tempaddr = (unsigned long) page_address(page); + struct cpa_data cpa = { .vaddr = &tempaddr, .numpages = numpages, .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW), - .mask_clr = __pgprot(0)}; + .mask_clr = __pgprot(0), + .flags = 0}; - return __change_page_attr_set_clr(&cpa, 1); + /* + * No alias checking needed for setting present flag. otherwise, + * we may need to break large pages for 64-bit kernel text + * mappings (this adds to complexity if we want to do this from + * atomic context especially). Let's keep it simple! + */ + return __change_page_attr_set_clr(&cpa, 0); } static int __set_pages_np(struct page *page, int numpages) { - struct cpa_data cpa = { .vaddr = (unsigned long) page_address(page), + unsigned long tempaddr = (unsigned long) page_address(page); + struct cpa_data cpa = { .vaddr = &tempaddr, .numpages = numpages, .mask_set = __pgprot(0), - .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW)}; + .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), + .flags = 0}; - return __change_page_attr_set_clr(&cpa, 1); + /* + * No alias checking needed for setting not present flag. otherwise, + * we may need to break large pages for 64-bit kernel text + * mappings (this adds to complexity if we want to do this from + * atomic context especially). Let's keep it simple! + */ + return __change_page_attr_set_clr(&cpa, 0); } void kernel_map_pages(struct page *page, int numpages, int enable) @@ -1010,11 +1101,8 @@ void kernel_map_pages(struct page *page, int numpages, int enable) /* * The return value is ignored as the calls cannot fail. - * Large pages are kept enabled at boot time, and are - * split up quickly with DEBUG_PAGEALLOC. If a splitup - * fails here (due to temporary memory shortage) no damage - * is done because we just keep the largepage intact up - * to the next attempt when it will likely be split up: + * Large pages for identity mappings are not used at boot time + * and hence no memory allocations during large page split. */ if (enable) __set_pages_p(page, numpages); @@ -1026,53 +1114,8 @@ void kernel_map_pages(struct page *page, int numpages, int enable) * but that can deadlock->flush only current cpu: */ __flush_tlb_all(); - - /* - * Try to refill the page pool here. We can do this only after - * the tlb flush. - */ - cpa_fill_pool(NULL); } -#ifdef CONFIG_DEBUG_FS -static int dpa_show(struct seq_file *m, void *v) -{ - seq_puts(m, "DEBUG_PAGEALLOC\n"); - seq_printf(m, "pool_size : %lu\n", pool_size); - seq_printf(m, "pool_pages : %lu\n", pool_pages); - seq_printf(m, "pool_low : %lu\n", pool_low); - seq_printf(m, "pool_used : %lu\n", pool_used); - seq_printf(m, "pool_failed : %lu\n", pool_failed); - - return 0; -} - -static int dpa_open(struct inode *inode, struct file *filp) -{ - return single_open(filp, dpa_show, NULL); -} - -static const struct file_operations dpa_fops = { - .open = dpa_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int __init debug_pagealloc_proc_init(void) -{ - struct dentry *de; - - de = debugfs_create_file("debug_pagealloc", 0600, NULL, NULL, - &dpa_fops); - if (!de) - return -ENOMEM; - - return 0; -} -__initcall(debug_pagealloc_proc_init); -#endif - #ifdef CONFIG_HIBERNATION bool kernel_page_present(struct page *page) diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 2a50e0fa64a..738fd0f2495 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -7,24 +7,24 @@ * Loosely based on earlier PAT patchset from Eric Biederman and Andi Kleen. */ -#include <linux/mm.h> +#include <linux/seq_file.h> +#include <linux/bootmem.h> +#include <linux/debugfs.h> #include <linux/kernel.h> #include <linux/gfp.h> +#include <linux/mm.h> #include <linux/fs.h> -#include <linux/bootmem.h> -#include <linux/debugfs.h> -#include <linux/seq_file.h> -#include <asm/msr.h> -#include <asm/tlbflush.h> +#include <asm/cacheflush.h> #include <asm/processor.h> -#include <asm/page.h> +#include <asm/tlbflush.h> #include <asm/pgtable.h> -#include <asm/pat.h> -#include <asm/e820.h> -#include <asm/cacheflush.h> #include <asm/fcntl.h> +#include <asm/e820.h> #include <asm/mtrr.h> +#include <asm/page.h> +#include <asm/msr.h> +#include <asm/pat.h> #include <asm/io.h> #ifdef CONFIG_X86_PAT @@ -46,6 +46,7 @@ early_param("nopat", nopat); static int debug_enable; + static int __init pat_debug_setup(char *str) { debug_enable = 1; @@ -145,14 +146,14 @@ static char *cattr_name(unsigned long flags) */ struct memtype { - u64 start; - u64 end; - unsigned long type; - struct list_head nd; + u64 start; + u64 end; + unsigned long type; + struct list_head nd; }; static LIST_HEAD(memtype_list); -static DEFINE_SPINLOCK(memtype_lock); /* protects memtype list */ +static DEFINE_SPINLOCK(memtype_lock); /* protects memtype list */ /* * Does intersection of PAT memory type and MTRR memory type and returns @@ -180,8 +181,8 @@ static unsigned long pat_x_mtrr_type(u64 start, u64 end, unsigned long req_type) return req_type; } -static int chk_conflict(struct memtype *new, struct memtype *entry, - unsigned long *type) +static int +chk_conflict(struct memtype *new, struct memtype *entry, unsigned long *type) { if (new->type != entry->type) { if (type) { @@ -211,6 +212,66 @@ static struct memtype *cached_entry; static u64 cached_start; /* + * For RAM pages, mark the pages as non WB memory type using + * PageNonWB (PG_arch_1). We allow only one set_memory_uc() or + * set_memory_wc() on a RAM page at a time before marking it as WB again. + * This is ok, because only one driver will be owning the page and + * doing set_memory_*() calls. + * + * For now, we use PageNonWB to track that the RAM page is being mapped + * as non WB. In future, we will have to use one more flag + * (or some other mechanism in page_struct) to distinguish between + * UC and WC mapping. + */ +static int reserve_ram_pages_type(u64 start, u64 end, unsigned long req_type, + unsigned long *new_type) +{ + struct page *page; + u64 pfn, end_pfn; + + for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) { + page = pfn_to_page(pfn); + if (page_mapped(page) || PageNonWB(page)) + goto out; + + SetPageNonWB(page); + } + return 0; + +out: + end_pfn = pfn; + for (pfn = (start >> PAGE_SHIFT); pfn < end_pfn; ++pfn) { + page = pfn_to_page(pfn); + ClearPageNonWB(page); + } + + return -EINVAL; +} + +static int free_ram_pages_type(u64 start, u64 end) +{ + struct page *page; + u64 pfn, end_pfn; + + for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) { + page = pfn_to_page(pfn); + if (page_mapped(page) || !PageNonWB(page)) + goto out; + + ClearPageNonWB(page); + } + return 0; + +out: + end_pfn = pfn; + for (pfn = (start >> PAGE_SHIFT); pfn < end_pfn; ++pfn) { + page = pfn_to_page(pfn); + SetPageNonWB(page); + } + return -EINVAL; +} + +/* * req_type typically has one of the: * - _PAGE_CACHE_WB * - _PAGE_CACHE_WC @@ -226,14 +287,15 @@ static u64 cached_start; * it will return a negative return value. */ int reserve_memtype(u64 start, u64 end, unsigned long req_type, - unsigned long *new_type) + unsigned long *new_type) { struct memtype *new, *entry; unsigned long actual_type; struct list_head *where; + int is_range_ram; int err = 0; - BUG_ON(start >= end); /* end is exclusive */ + BUG_ON(start >= end); /* end is exclusive */ if (!pat_enabled) { /* This is identical to page table setting without PAT */ @@ -266,17 +328,24 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type, actual_type = _PAGE_CACHE_WB; else actual_type = _PAGE_CACHE_UC_MINUS; - } else + } else { actual_type = pat_x_mtrr_type(start, end, req_type & _PAGE_CACHE_MASK); + } + + is_range_ram = pagerange_is_ram(start, end); + if (is_range_ram == 1) + return reserve_ram_pages_type(start, end, req_type, new_type); + else if (is_range_ram < 0) + return -EINVAL; new = kmalloc(sizeof(struct memtype), GFP_KERNEL); if (!new) return -ENOMEM; - new->start = start; - new->end = end; - new->type = actual_type; + new->start = start; + new->end = end; + new->type = actual_type; if (new_type) *new_type = actual_type; @@ -335,6 +404,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type, start, end, cattr_name(new->type), cattr_name(req_type)); kfree(new); spin_unlock(&memtype_lock); + return err; } @@ -358,6 +428,7 @@ int free_memtype(u64 start, u64 end) { struct memtype *entry; int err = -EINVAL; + int is_range_ram; if (!pat_enabled) return 0; @@ -366,6 +437,12 @@ int free_memtype(u64 start, u64 end) if (is_ISA_range(start, end - 1)) return 0; + is_range_ram = pagerange_is_ram(start, end); + if (is_range_ram == 1) + return free_ram_pages_type(start, end); + else if (is_range_ram < 0) + return -EINVAL; + spin_lock(&memtype_lock); list_for_each_entry(entry, &memtype_list, nd) { if (entry->start == start && entry->end == end) { @@ -386,6 +463,7 @@ int free_memtype(u64 start, u64 end) } dprintk("free_memtype request 0x%Lx-0x%Lx\n", start, end); + return err; } @@ -492,9 +570,9 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn, void map_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot) { + unsigned long want_flags = (pgprot_val(vma_prot) & _PAGE_CACHE_MASK); u64 addr = (u64)pfn << PAGE_SHIFT; unsigned long flags; - unsigned long want_flags = (pgprot_val(vma_prot) & _PAGE_CACHE_MASK); reserve_memtype(addr, addr + size, want_flags, &flags); if (flags != want_flags) { @@ -514,7 +592,7 @@ void unmap_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot) free_memtype(addr, addr + size); } -#if defined(CONFIG_DEBUG_FS) +#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT) /* get Nth element of the linked list */ static struct memtype *memtype_get_idx(loff_t pos) @@ -537,6 +615,7 @@ static struct memtype *memtype_get_idx(loff_t pos) } spin_unlock(&memtype_lock); kfree(print_entry); + return NULL; } @@ -567,6 +646,7 @@ static int memtype_seq_show(struct seq_file *seq, void *v) seq_printf(seq, "%s @ 0x%Lx-0x%Lx\n", cattr_name(print_entry->type), print_entry->start, print_entry->end); kfree(print_entry); + return 0; } @@ -598,4 +678,4 @@ static int __init pat_memtype_list_init(void) late_initcall(pat_memtype_list_init); -#endif /* CONFIG_DEBUG_FS */ +#endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */ |