1 files changed, 85 insertions, 0 deletions

diff --git a/drivers/block/loop.h b/drivers/block/loop.h
new file mode 100644
index 000000000000..90df5d6485b6
--- /dev/null
+++ b/drivers/block/loop.h
@@ -0,0 +1,85 @@
+/*
+ * loop.h
+ *
+ * Written by Theodore Ts'o, 3/29/93.
+ *
+ * Copyright 1993 by Theodore Ts'o.  Redistribution of this file is
+ * permitted under the GNU General Public License.
+ */
+#ifndef _LINUX_LOOP_H
+#define _LINUX_LOOP_H
+
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <uapi/linux/loop.h>
+
+/* Possible states of device */
+enum {
+        Lo_unbound,
+        Lo_bound,
+        Lo_rundown,
+};
+
+struct loop_func_table;
+
+struct loop_device {
+        int             lo_number;
+        int             lo_refcnt;
+        loff_t          lo_offset;
+        loff_t          lo_sizelimit;
+        int             lo_flags;
+        int             (*transfer)(struct loop_device *, int cmd,
+                                    struct page *raw_page, unsigned raw_off,
+                                    struct page *loop_page, unsigned loop_off,
+                                    int size, sector_t real_block);
+        char            lo_file_name[LO_NAME_SIZE];
+        char            lo_crypt_name[LO_NAME_SIZE];
+        char            lo_encrypt_key[LO_KEY_SIZE];
+        int             lo_encrypt_key_size;
+        struct loop_func_table *lo_encryption;
+        __u32           lo_init[2];
+        kuid_t          lo_key_owner;   /* Who set the key */
+        int             (*ioctl)(struct loop_device *, int cmd, 
+                                 unsigned long arg); 
+
+        struct file *   lo_backing_file;
+        struct block_device *lo_device;
+        unsigned        lo_blocksize;
+        void            *key_data; 
+
+        gfp_t           old_gfp_mask;
+
+        spinlock_t              lo_lock;
+        struct bio_list         lo_bio_list;
+        unsigned int            lo_bio_count;
+        int                     lo_state;
+        struct mutex            lo_ctl_mutex;
+        struct task_struct      *lo_thread;
+        wait_queue_head_t       lo_event;
+        /* wait queue for incoming requests */
+        wait_queue_head_t       lo_req_wait;
+
+        struct request_queue    *lo_queue;
+        struct gendisk          *lo_disk;
+};
+
+/* Support for loadable transfer modules */
+struct loop_func_table {
+        int number;     /* filter type */ 
+        int (*transfer)(struct loop_device *lo, int cmd,
+                        struct page *raw_page, unsigned raw_off,
+                        struct page *loop_page, unsigned loop_off,
+                        int size, sector_t real_block);
+        int (*init)(struct loop_device *, const struct loop_info64 *); 
+        /* release is called from loop_unregister_transfer or clr_fd */
+        int (*release)(struct loop_device *); 
+        int (*ioctl)(struct loop_device *, int cmd, unsigned long arg);
+        struct module *owner;
+}; 
+
+int loop_register_transfer(struct loop_func_table *funcs);
+int loop_unregister_transfer(int number); 
+
+#endif