summaryrefslogtreecommitdiff
path: root/drivers/block/loop.h
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/block/loop.h
Initial import
Diffstat (limited to 'drivers/block/loop.h')
-rw-r--r--drivers/block/loop.h92
1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/block/loop.h b/drivers/block/loop.h
new file mode 100644
index 000000000..49564edf5
--- /dev/null
+++ b/drivers/block/loop.h
@@ -0,0 +1,92 @@
+/*
+ * 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/blk-mq.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.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 workqueue_struct *wq;
+ struct list_head write_cmd_head;
+ struct work_struct write_work;
+ bool write_started;
+ int lo_state;
+ struct mutex lo_ctl_mutex;
+
+ struct request_queue *lo_queue;
+ struct blk_mq_tag_set tag_set;
+ struct gendisk *lo_disk;
+};
+
+struct loop_cmd {
+ struct work_struct read_work;
+ struct request *rq;
+ struct list_head list;
+};
+
+/* 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