diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 7 | ||||
| -rw-r--r-- | arch/x86/include/asm/pgalloc.h | 5 | ||||
| -rw-r--r-- | arch/x86/mm/pgtable.c | 31 |
3 files changed, 38 insertions, 5 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 5bc4eaaa5b7f..345c3998ec42 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2668,6 +2668,13 @@ and is between 256 and 4096 characters. It is defined in the file medium is write-protected). Example: quirks=0419:aaf5:rl,0421:0433:rc + userpte= + [X86] Flags controlling user PTE allocations. + + nohigh = do not allocate PTE pages in + HIGHMEM regardless of setting + of CONFIG_HIGHPTE. + vdso= [X86,SH] vdso=2: enable compat VDSO (default with COMPAT_VDSO) vdso=1: enable VDSO (default) diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h index 0e8c2a0fd922..271de94c3810 100644 --- a/arch/x86/include/asm/pgalloc.h +++ b/arch/x86/include/asm/pgalloc.h @@ -23,6 +23,11 @@ static inline void paravirt_release_pud(unsigned long pfn) {} #endif /* + * Flags to use when allocating a user page table page. + */ +extern gfp_t __userpte_alloc_gfp; + +/* * Allocate and free page tables. */ extern pgd_t *pgd_alloc(struct mm_struct *); diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index ed34f5e35999..c9ba9deafe83 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -6,6 +6,14 @@ #define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO +#ifdef CONFIG_HIGHPTE +#define PGALLOC_USER_GFP __GFP_HIGHMEM +#else +#define PGALLOC_USER_GFP 0 +#endif + +gfp_t __userpte_alloc_gfp = PGALLOC_GFP | PGALLOC_USER_GFP; + pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) { return (pte_t *)__get_free_page(PGALLOC_GFP); @@ -15,16 +23,29 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address) { struct page *pte; -#ifdef CONFIG_HIGHPTE - pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0); -#else - pte = alloc_pages(PGALLOC_GFP, 0); -#endif + pte = alloc_pages(__userpte_alloc_gfp, 0); if (pte) pgtable_page_ctor(pte); return pte; } +static int __init setup_userpte(char *arg) +{ + if (!arg) + return -EINVAL; + + /* + * "userpte=nohigh" disables allocation of user pagetables in + * high memory. + */ + if (strcmp(arg, "nohigh") == 0) + __userpte_alloc_gfp &= ~__GFP_HIGHMEM; + else + return -EINVAL; + return 0; +} +early_param("userpte", setup_userpte); + void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte) { pgtable_page_dtor(pte); |