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-rw-r--r--drivers/md/dm.h195
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
new file mode 100644
index 000000000000..e38c3fc1a1db
--- /dev/null
+++ b/drivers/md/dm.h
@@ -0,0 +1,195 @@
+/*
+ * Internal header file for device mapper
+ *
+ * Copyright (C) 2001, 2002 Sistina Software
+ * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
+ *
+ * This file is released under the LGPL.
+ */
+
+#ifndef DM_INTERNAL_H
+#define DM_INTERNAL_H
+
+#include <linux/fs.h>
+#include <linux/device-mapper.h>
+#include <linux/list.h>
+#include <linux/blkdev.h>
+
+#define DM_NAME "device-mapper"
+#define DMWARN(f, x...) printk(KERN_WARNING DM_NAME ": " f "\n" , ## x)
+#define DMERR(f, x...) printk(KERN_ERR DM_NAME ": " f "\n" , ## x)
+#define DMINFO(f, x...) printk(KERN_INFO DM_NAME ": " f "\n" , ## x)
+
+#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
+ 0 : scnprintf(result + sz, maxlen - sz, x))
+
+/*
+ * FIXME: I think this should be with the definition of sector_t
+ * in types.h.
+ */
+#ifdef CONFIG_LBD
+#define SECTOR_FORMAT "%Lu"
+#else
+#define SECTOR_FORMAT "%lu"
+#endif
+
+#define SECTOR_SHIFT 9
+
+/*
+ * List of devices that a metadevice uses and should open/close.
+ */
+struct dm_dev {
+ struct list_head list;
+
+ atomic_t count;
+ int mode;
+ struct block_device *bdev;
+ char name[16];
+};
+
+struct dm_table;
+struct mapped_device;
+
+/*-----------------------------------------------------------------
+ * Functions for manipulating a struct mapped_device.
+ * Drop the reference with dm_put when you finish with the object.
+ *---------------------------------------------------------------*/
+int dm_create(struct mapped_device **md);
+int dm_create_with_minor(unsigned int minor, struct mapped_device **md);
+void dm_set_mdptr(struct mapped_device *md, void *ptr);
+void *dm_get_mdptr(dev_t dev);
+
+/*
+ * Reference counting for md.
+ */
+void dm_get(struct mapped_device *md);
+void dm_put(struct mapped_device *md);
+
+/*
+ * A device can still be used while suspended, but I/O is deferred.
+ */
+int dm_suspend(struct mapped_device *md);
+int dm_resume(struct mapped_device *md);
+
+/*
+ * The device must be suspended before calling this method.
+ */
+int dm_swap_table(struct mapped_device *md, struct dm_table *t);
+
+/*
+ * Drop a reference on the table when you've finished with the
+ * result.
+ */
+struct dm_table *dm_get_table(struct mapped_device *md);
+
+/*
+ * Event functions.
+ */
+uint32_t dm_get_event_nr(struct mapped_device *md);
+int dm_wait_event(struct mapped_device *md, int event_nr);
+
+/*
+ * Info functions.
+ */
+struct gendisk *dm_disk(struct mapped_device *md);
+int dm_suspended(struct mapped_device *md);
+
+/*-----------------------------------------------------------------
+ * Functions for manipulating a table. Tables are also reference
+ * counted.
+ *---------------------------------------------------------------*/
+int dm_table_create(struct dm_table **result, int mode, unsigned num_targets);
+
+void dm_table_get(struct dm_table *t);
+void dm_table_put(struct dm_table *t);
+
+int dm_table_add_target(struct dm_table *t, const char *type,
+ sector_t start, sector_t len, char *params);
+int dm_table_complete(struct dm_table *t);
+void dm_table_event_callback(struct dm_table *t,
+ void (*fn)(void *), void *context);
+void dm_table_event(struct dm_table *t);
+sector_t dm_table_get_size(struct dm_table *t);
+struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
+struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
+void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q);
+unsigned int dm_table_get_num_targets(struct dm_table *t);
+struct list_head *dm_table_get_devices(struct dm_table *t);
+int dm_table_get_mode(struct dm_table *t);
+void dm_table_presuspend_targets(struct dm_table *t);
+void dm_table_postsuspend_targets(struct dm_table *t);
+void dm_table_resume_targets(struct dm_table *t);
+int dm_table_any_congested(struct dm_table *t, int bdi_bits);
+void dm_table_unplug_all(struct dm_table *t);
+int dm_table_flush_all(struct dm_table *t);
+
+/*-----------------------------------------------------------------
+ * A registry of target types.
+ *---------------------------------------------------------------*/
+int dm_target_init(void);
+void dm_target_exit(void);
+struct target_type *dm_get_target_type(const char *name);
+void dm_put_target_type(struct target_type *t);
+int dm_target_iterate(void (*iter_func)(struct target_type *tt,
+ void *param), void *param);
+
+
+/*-----------------------------------------------------------------
+ * Useful inlines.
+ *---------------------------------------------------------------*/
+static inline int array_too_big(unsigned long fixed, unsigned long obj,
+ unsigned long num)
+{
+ return (num > (ULONG_MAX - fixed) / obj);
+}
+
+/*
+ * 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))
+
+static inline sector_t to_sector(unsigned long n)
+{
+ return (n >> 9);
+}
+
+static inline unsigned long to_bytes(sector_t n)
+{
+ return (n << 9);
+}
+
+int dm_split_args(int *argc, char ***argvp, char *input);
+
+/*
+ * The device-mapper can be driven through one of two interfaces;
+ * ioctl or filesystem, depending which patch you have applied.
+ */
+int dm_interface_init(void);
+void dm_interface_exit(void);
+
+/*
+ * Targets for linear and striped mappings
+ */
+int dm_linear_init(void);
+void dm_linear_exit(void);
+
+int dm_stripe_init(void);
+void dm_stripe_exit(void);
+
+void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
+union map_info *dm_get_mapinfo(struct bio *bio);
+
+#endif