This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / include / linux / mm_types.h

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
new file mode 100644 (file)
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--- /dev/null
+++ b/include/linux/mm_types.h
@@ -0,0 +1,67 @@
+#ifndef _LINUX_MM_TYPES_H
+#define _LINUX_MM_TYPES_H
+
+#include <linux/types.h>
+#include <linux/threads.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+
+struct address_space;
+
+/*
+ * Each physical page in the system has a struct page associated with
+ * it to keep track of whatever it is we are using the page for at the
+ * moment. Note that we have no way to track which tasks are using
+ * a page, though if it is a pagecache page, rmap structures can tell us
+ * who is mapping it.
+ */
+struct page {
+       unsigned long flags;            /* Atomic flags, some possibly
+                                        * updated asynchronously */
+       atomic_t _count;                /* Usage count, see below. */
+       atomic_t _mapcount;             /* Count of ptes mapped in mms,
+                                        * to show when page is mapped
+                                        * & limit reverse map searches.
+                                        */
+       union {
+           struct {
+               unsigned long private;          /* Mapping-private opaque data:
+                                                * usually used for buffer_heads
+                                                * if PagePrivate set; used for
+                                                * swp_entry_t if PageSwapCache;
+                                                * indicates order in the buddy
+                                                * system if PG_buddy is set.
+                                                */
+               struct address_space *mapping;  /* If low bit clear, points to
+                                                * inode address_space, or NULL.
+                                                * If page mapped as anonymous
+                                                * memory, low bit is set, and
+                                                * it points to anon_vma object:
+                                                * see PAGE_MAPPING_ANON below.
+                                                */
+           };
+#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
+           spinlock_t ptl;
+#endif
+       };
+       pgoff_t index;                  /* Our offset within mapping. */
+       struct list_head lru;           /* Pageout list, eg. active_list
+                                        * protected by zone->lru_lock !
+                                        */
+       /*
+        * On machines where all RAM is mapped into kernel address space,
+        * we can simply calculate the virtual address. On machines with
+        * highmem some memory is mapped into kernel virtual memory
+        * dynamically, so we need a place to store that address.
+        * Note that this field could be 16 bits on x86 ... ;)
+        *
+        * Architectures with slow multiplication can define
+        * WANT_PAGE_VIRTUAL in asm/page.h
+        */
+#if defined(WANT_PAGE_VIRTUAL)
+       void *virtual;                  /* Kernel virtual address (NULL if
+                                          not kmapped, ie. highmem) */
+#endif /* WANT_PAGE_VIRTUAL */
+};
+
+#endif /* _LINUX_MM_TYPES_H */