+void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
+
+/*-----------------------------------------------------------------
+ * Macros.
+ *---------------------------------------------------------------*/
+#define DM_NAME "device-mapper"
+
+#define DMCRIT(f, arg...) \
+ printk(KERN_CRIT DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
+
+#define DMERR(f, arg...) \
+ printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
+#define DMERR_LIMIT(f, arg...) \
+ do { \
+ if (printk_ratelimit()) \
+ printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " \
+ f "\n", ## arg); \
+ } while (0)
+
+#define DMWARN(f, arg...) \
+ printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
+#define DMWARN_LIMIT(f, arg...) \
+ do { \
+ if (printk_ratelimit()) \
+ printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " \
+ f "\n", ## arg); \
+ } while (0)
+
+#define DMINFO(f, arg...) \
+ printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
+#define DMINFO_LIMIT(f, arg...) \
+ do { \
+ if (printk_ratelimit()) \
+ printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f \
+ "\n", ## arg); \
+ } while (0)
+
+#ifdef CONFIG_DM_DEBUG
+# define DMDEBUG(f, arg...) \
+ printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg)
+# define DMDEBUG_LIMIT(f, arg...) \
+ do { \
+ if (printk_ratelimit()) \
+ printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX ": " f \
+ "\n", ## arg); \
+ } while (0)
+#else
+# define DMDEBUG(f, arg...) do {} while (0)
+# define DMDEBUG_LIMIT(f, arg...) do {} while (0)
+#endif
+
+#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
+ 0 : scnprintf(result + sz, maxlen - sz, x))
+
+#define SECTOR_SHIFT 9
+
+/*
+ * Definitions of return values from target end_io function.
+ */
+#define DM_ENDIO_INCOMPLETE 1
+#define DM_ENDIO_REQUEUE 2
+
+/*
+ * Definitions of return values from target map function.
+ */
+#define DM_MAPIO_SUBMITTED 0
+#define DM_MAPIO_REMAPPED 1
+#define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE
+
+/*
+ * Ceiling(n / sz)
+ */
+#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))
+
+#define dm_sector_div_up(n, sz) ( \
+{ \
+ sector_t _r = ((n) + (sz) - 1); \
+ sector_div(_r, (sz)); \
+ _r; \
+} \
+)
+
+/*
+ * ceiling(n / size) * size
+ */
+#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
+
+#define dm_array_too_big(fixed, obj, num) \
+ ((num) > (UINT_MAX - (fixed)) / (obj))
+
+static inline sector_t to_sector(unsigned long n)
+{
+ return (n >> SECTOR_SHIFT);
+}
+
+static inline unsigned long to_bytes(sector_t n)
+{
+ return (n << SECTOR_SHIFT);
+}
+
+/*-----------------------------------------------------------------
+ * Helper for block layer and dm core operations
+ *---------------------------------------------------------------*/
+void dm_dispatch_request(struct request *rq);
+void dm_requeue_unmapped_request(struct request *rq);
+void dm_kill_unmapped_request(struct request *rq, int error);
+int dm_underlying_device_busy(struct request_queue *q);