patch-1.3.57 linux/include/linux/swap.h

• Lines: 135
• Date: Wed Jan 10 09:27:40 1996
• Orig file: v1.3.56/linux/include/linux/swap.h
• Orig date: Fri Jun 16 22:02:55 1995

diff -u --recursive --new-file v1.3.56/linux/include/linux/swap.h linux/include/linux/swap.h
@@ -5,4 +5,134 @@
 #define SWAP_FLAG_PRIO_MASK	0x7fff
 #define SWAP_FLAG_PRIO_SHIFT	0
 
+#define MAX_SWAPFILES 8
+
+#ifdef __KERNEL__
+
+#define SWP_USED	1
+#define SWP_WRITEOK	3
+
+struct swap_info_struct {
+	unsigned int flags;
+	kdev_t swap_device;
+	struct inode * swap_file;
+	unsigned char * swap_map;
+	unsigned char * swap_lockmap;
+	int lowest_bit;
+	int highest_bit;
+	int prio;			/* swap priority */
+	int pages;
+	unsigned long max;
+	int next;			/* next entry on swap list */
+};
+
+extern int nr_swap_pages;
+extern int nr_free_pages;
+extern int min_free_pages;
+extern int free_pages_low;
+extern int free_pages_high;
+
+/* Incomplete types for prototype declarations: */
+struct task_struct;
+struct vm_area_struct;
+struct sysinfo;
+
+/* linux/ipc/shm.c */
+extern int shm_swap (int, unsigned long);
+
+/* linux/mm/swap_clock.c */
+extern int try_to_free_page(int, unsigned long);
+
+/* linux/mm/swap_io.c */
+extern void rw_swap_page(int, unsigned long, char *);
+#define read_swap_page(nr,buf) \
+	rw_swap_page(READ,(nr),(buf))
+#define write_swap_page(nr,buf) \
+	rw_swap_page(WRITE,(nr),(buf))
+
+/* linux/mm/swap_mman.c */
+extern void swap_in(struct task_struct *, struct vm_area_struct *,
+		    pte_t *, unsigned long, int);
+
+
+/* linux/mm/swap_state.c */
+extern void show_swap_cache_info(void);
+extern int add_to_swap_cache(unsigned long, unsigned long);
+extern unsigned long init_swap_cache(unsigned long, unsigned long);
+extern void swap_duplicate(unsigned long);
+
+/* linux/mm/swapfile.c */
+extern int nr_swapfiles;
+extern struct swap_info_struct swap_info[];
+void si_swapinfo(struct sysinfo *);
+unsigned long get_swap_page(void);
+extern void swap_free(unsigned long);
+
+/*
+ * vm_ops not present page codes for shared memory.
+ *
+ * Will go away eventually..
+ */
+#define SHM_SWP_TYPE 0x40
+
+extern void shm_no_page (ulong *);
+
+/*
+ * swap cache stuff (in linux/mm/swap_state.c)
+ */
+
+#define SWAP_CACHE_INFO
+
+extern unsigned long * swap_cache;
+
+#ifdef SWAP_CACHE_INFO
+extern unsigned long swap_cache_add_total;
+extern unsigned long swap_cache_add_success;
+extern unsigned long swap_cache_del_total;
+extern unsigned long swap_cache_del_success;
+extern unsigned long swap_cache_find_total;
+extern unsigned long swap_cache_find_success;
+#endif
+
+extern inline unsigned long in_swap_cache(unsigned long addr)
+{
+	return swap_cache[MAP_NR(addr)]; 
+}
+
+extern inline long find_in_swap_cache (unsigned long addr)
+{
+	unsigned long entry;
+
+#ifdef SWAP_CACHE_INFO
+	swap_cache_find_total++;
+#endif
+	entry = xchg(swap_cache + MAP_NR(addr), 0);
+#ifdef SWAP_CACHE_INFO
+	if (entry)
+		swap_cache_find_success++;
+#endif	
+	return entry;
+}
+
+extern inline int delete_from_swap_cache(unsigned long addr)
+{
+	unsigned long entry;
+	
+#ifdef SWAP_CACHE_INFO
+	swap_cache_del_total++;
+#endif	
+	entry= xchg(swap_cache + MAP_NR(addr), 0);
+	if (entry)  {
+#ifdef SWAP_CACHE_INFO
+		swap_cache_del_success++;
+#endif
+		swap_free(entry);
+		return 1;
+	}
+	return 0;
+}
+
+
+#endif /* __KERNEL__*/
+
 #endif /* _LINUX_SWAP_H */