diff options
Diffstat (limited to 'include/linux/mm.h')
| -rw-r--r-- | include/linux/mm.h | 141 |
1 files changed, 123 insertions, 18 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 1813b162b0a8..82d7024f0765 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -395,19 +395,81 @@ static inline void put_page(struct page *page) /* * The zone field is never updated after free_area_init_core() * sets it, so none of the operations on it need to be atomic. - * We'll have up to (MAX_NUMNODES * MAX_NR_ZONES) zones total, - * so we use (MAX_NODES_SHIFT + MAX_ZONES_SHIFT) here to get enough bits. */ -#define NODEZONE_SHIFT (sizeof(page_flags_t)*8 - MAX_NODES_SHIFT - MAX_ZONES_SHIFT) -#define NODEZONE(node, zone) ((node << ZONES_SHIFT) | zone) + + +/* + * page->flags layout: + * + * There are three possibilities for how page->flags get + * laid out. The first is for the normal case, without + * sparsemem. The second is for sparsemem when there is + * plenty of space for node and section. The last is when + * we have run out of space and have to fall back to an + * alternate (slower) way of determining the node. + * + * No sparsemem: | NODE | ZONE | ... | FLAGS | + * with space for node: | SECTION | NODE | ZONE | ... | FLAGS | + * no space for node: | SECTION | ZONE | ... | FLAGS | + */ +#ifdef CONFIG_SPARSEMEM +#define SECTIONS_WIDTH SECTIONS_SHIFT +#else +#define SECTIONS_WIDTH 0 +#endif + +#define ZONES_WIDTH ZONES_SHIFT + +#if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT <= FLAGS_RESERVED +#define NODES_WIDTH NODES_SHIFT +#else +#define NODES_WIDTH 0 +#endif + +/* Page flags: | [SECTION] | [NODE] | ZONE | ... | FLAGS | */ +#define SECTIONS_PGOFF ((sizeof(page_flags_t)*8) - SECTIONS_WIDTH) +#define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH) +#define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH) + +/* + * We are going to use the flags for the page to node mapping if its in + * there. This includes the case where there is no node, so it is implicit. + */ +#define FLAGS_HAS_NODE (NODES_WIDTH > 0 || NODES_SHIFT == 0) + +#ifndef PFN_SECTION_SHIFT +#define PFN_SECTION_SHIFT 0 +#endif + +/* + * Define the bit shifts to access each section. For non-existant + * sections we define the shift as 0; that plus a 0 mask ensures + * the compiler will optimise away reference to them. + */ +#define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0)) +#define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0)) +#define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0)) + +/* NODE:ZONE or SECTION:ZONE is used to lookup the zone from a page. */ +#if FLAGS_HAS_NODE +#define ZONETABLE_SHIFT (NODES_SHIFT + ZONES_SHIFT) +#else +#define ZONETABLE_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT) +#endif +#define ZONETABLE_PGSHIFT ZONES_PGSHIFT + +#if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED +#error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED +#endif + +#define ZONES_MASK ((1UL << ZONES_WIDTH) - 1) +#define NODES_MASK ((1UL << NODES_WIDTH) - 1) +#define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1) +#define ZONETABLE_MASK ((1UL << ZONETABLE_SHIFT) - 1) static inline unsigned long page_zonenum(struct page *page) { - return (page->flags >> NODEZONE_SHIFT) & (~(~0UL << ZONES_SHIFT)); -} -static inline unsigned long page_to_nid(struct page *page) -{ - return (page->flags >> (NODEZONE_SHIFT + ZONES_SHIFT)); + return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; } struct zone; @@ -415,13 +477,44 @@ extern struct zone *zone_table[]; static inline struct zone *page_zone(struct page *page) { - return zone_table[page->flags >> NODEZONE_SHIFT]; + return zone_table[(page->flags >> ZONETABLE_PGSHIFT) & + ZONETABLE_MASK]; +} + +static inline unsigned long page_to_nid(struct page *page) +{ + if (FLAGS_HAS_NODE) + return (page->flags >> NODES_PGSHIFT) & NODES_MASK; + else + return page_zone(page)->zone_pgdat->node_id; +} +static inline unsigned long page_to_section(struct page *page) +{ + return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; } -static inline void set_page_zone(struct page *page, unsigned long nodezone_num) +static inline void set_page_zone(struct page *page, unsigned long zone) { - page->flags &= ~(~0UL << NODEZONE_SHIFT); - page->flags |= nodezone_num << NODEZONE_SHIFT; + page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); + page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; +} +static inline void set_page_node(struct page *page, unsigned long node) +{ + page->flags &= ~(NODES_MASK << NODES_PGSHIFT); + page->flags |= (node & NODES_MASK) << NODES_PGSHIFT; +} +static inline void set_page_section(struct page *page, unsigned long section) +{ + page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT); + page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; +} + +static inline void set_page_links(struct page *page, unsigned long zone, + unsigned long node, unsigned long pfn) +{ + set_page_zone(page, zone); + set_page_node(page, node); + set_page_section(page, pfn_to_section_nr(pfn)); } #ifndef CONFIG_DISCONTIGMEM @@ -532,10 +625,16 @@ static inline int page_mapped(struct page *page) * Used to decide whether a process gets delivered SIGBUS or * just gets major/minor fault counters bumped up. */ -#define VM_FAULT_OOM (-1) -#define VM_FAULT_SIGBUS 0 -#define VM_FAULT_MINOR 1 -#define VM_FAULT_MAJOR 2 +#define VM_FAULT_OOM 0x00 +#define VM_FAULT_SIGBUS 0x01 +#define VM_FAULT_MINOR 0x02 +#define VM_FAULT_MAJOR 0x03 + +/* + * Special case for get_user_pages. + * Must be in a distinct bit from the above VM_FAULT_ flags. + */ +#define VM_FAULT_WRITE 0x10 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) @@ -611,7 +710,13 @@ extern pte_t *FASTCALL(pte_alloc_kernel(struct mm_struct *mm, pmd_t *pmd, unsign extern pte_t *FASTCALL(pte_alloc_map(struct mm_struct *mm, pmd_t *pmd, unsigned long address)); extern int install_page(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, struct page *page, pgprot_t prot); extern int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned long pgoff, pgprot_t prot); -extern int handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, unsigned long address, int write_access); +extern int __handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, unsigned long address, int write_access); + +static inline int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, int write_access) +{ + return __handle_mm_fault(mm, vma, address, write_access) & (~VM_FAULT_WRITE); +} + extern int make_pages_present(unsigned long addr, unsigned long end); extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write); void install_arg_page(struct vm_area_struct *, struct page *, unsigned long); |