#define VM_EXEC 0x00000004
#define VM_SHARED 0x00000008
+/* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
#define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */
#define VM_MAYWRITE 0x00000020
#define VM_MAYEXEC 0x00000040
* only one copy in memory, at most, normally.
*
* For the non-reserved pages, page_count(page) denotes a reference count.
- * page_count() == 0 means the page is free.
+ * page_count() == 0 means the page is free. page->lru is then used for
+ * freelist management in the buddy allocator.
* page_count() == 1 means the page is used for exactly one purpose
* (e.g. a private data page of one process).
*
* attaches, plus 1 if `private' contains something, plus one for
* the page cache itself.
*
- * All pages belonging to an inode are in these doubly linked lists:
- * mapping->clean_pages, mapping->dirty_pages and mapping->locked_pages;
- * using the page->list list_head. These fields are also used for
- * freelist managemet (when page_count()==0).
+ * Instead of keeping dirty/clean pages in per address-space lists, we instead
+ * now tag pages as dirty/under writeback in the radix tree.
*
* There is also a per-mapping radix tree mapping index to the page
* in memory if present. The tree is rooted at mapping->root.
* sets it, so none of the operations on it need to be atomic.
*/
-/* Page flags: | NODE | ZONE | ... | FLAGS | */
-#define NODES_PGOFF ((sizeof(page_flags_t)*8) - NODES_SHIFT)
-#define ZONES_PGOFF (NODES_PGOFF - ZONES_SHIFT)
+
+/*
+ * 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 NODES_PGSHIFT (NODES_PGOFF * (NODES_SHIFT != 0))
-#define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_SHIFT != 0))
+#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 is used to lookup the zone from a page. */
+/* 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 NODES_SHIFT+ZONES_SHIFT > FLAGS_RESERVED
-#error NODES_SHIFT+ZONES_SHIFT > FLAGS_RESERVED
+#if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED
+#error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED
#endif
-#define NODEZONE(node, zone) ((node << ZONES_SHIFT) | zone)
-
-#define ZONES_MASK ((1UL << ZONES_SHIFT) - 1)
-#define NODES_MASK ((1UL << NODES_SHIFT) - 1)
+#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 >> ZONES_PGSHIFT) & ZONES_MASK;
}
-static inline unsigned long page_to_nid(struct page *page)
-{
- return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
-}
struct zone;
extern struct zone *zone_table[];
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 zone)
{
page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
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 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
* 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)
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);