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-rw-r--r--include/linux/loop.h161
1 files changed, 161 insertions, 0 deletions
diff --git a/include/linux/loop.h b/include/linux/loop.h
new file mode 100644
index 00000000000..8220d9c9da0
--- /dev/null
+++ b/include/linux/loop.h
@@ -0,0 +1,161 @@
+#ifndef _LINUX_LOOP_H
+#define _LINUX_LOOP_H
+
+/*
+ * include/linux/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.
+ */
+
+#define LO_NAME_SIZE 64
+#define LO_KEY_SIZE 32
+
+#ifdef __KERNEL__
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/spinlock.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];
+ uid_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;
+
+ int old_gfp_mask;
+
+ spinlock_t lo_lock;
+ struct bio *lo_bio;
+ struct bio *lo_biotail;
+ int lo_state;
+ struct semaphore lo_sem;
+ struct semaphore lo_ctl_mutex;
+ struct semaphore lo_bh_mutex;
+ atomic_t lo_pending;
+
+ request_queue_t *lo_queue;
+};
+
+#endif /* __KERNEL__ */
+
+/*
+ * Loop flags
+ */
+enum {
+ LO_FLAGS_READ_ONLY = 1,
+ LO_FLAGS_USE_AOPS = 2,
+};
+
+#include <asm/posix_types.h> /* for __kernel_old_dev_t */
+#include <asm/types.h> /* for __u64 */
+
+/* Backwards compatibility version */
+struct loop_info {
+ int lo_number; /* ioctl r/o */
+ __kernel_old_dev_t lo_device; /* ioctl r/o */
+ unsigned long lo_inode; /* ioctl r/o */
+ __kernel_old_dev_t lo_rdevice; /* ioctl r/o */
+ int lo_offset;
+ int lo_encrypt_type;
+ int lo_encrypt_key_size; /* ioctl w/o */
+ int lo_flags; /* ioctl r/o */
+ char lo_name[LO_NAME_SIZE];
+ unsigned char lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
+ unsigned long lo_init[2];
+ char reserved[4];
+};
+
+struct loop_info64 {
+ __u64 lo_device; /* ioctl r/o */
+ __u64 lo_inode; /* ioctl r/o */
+ __u64 lo_rdevice; /* ioctl r/o */
+ __u64 lo_offset;
+ __u64 lo_sizelimit;/* bytes, 0 == max available */
+ __u32 lo_number; /* ioctl r/o */
+ __u32 lo_encrypt_type;
+ __u32 lo_encrypt_key_size; /* ioctl w/o */
+ __u32 lo_flags; /* ioctl r/o */
+ __u8 lo_file_name[LO_NAME_SIZE];
+ __u8 lo_crypt_name[LO_NAME_SIZE];
+ __u8 lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
+ __u64 lo_init[2];
+};
+
+/*
+ * Loop filter types
+ */
+
+#define LO_CRYPT_NONE 0
+#define LO_CRYPT_XOR 1
+#define LO_CRYPT_DES 2
+#define LO_CRYPT_FISH2 3 /* Twofish encryption */
+#define LO_CRYPT_BLOW 4
+#define LO_CRYPT_CAST128 5
+#define LO_CRYPT_IDEA 6
+#define LO_CRYPT_DUMMY 9
+#define LO_CRYPT_SKIPJACK 10
+#define LO_CRYPT_CRYPTOAPI 18
+#define MAX_LO_CRYPT 20
+
+#ifdef __KERNEL__
+/* 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
+/*
+ * IOCTL commands --- we will commandeer 0x4C ('L')
+ */
+
+#define LOOP_SET_FD 0x4C00
+#define LOOP_CLR_FD 0x4C01
+#define LOOP_SET_STATUS 0x4C02
+#define LOOP_GET_STATUS 0x4C03
+#define LOOP_SET_STATUS64 0x4C04
+#define LOOP_GET_STATUS64 0x4C05
+#define LOOP_CHANGE_FD 0x4C06
+
+#endif