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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/block/loop.h
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/block/loop.h')
-rw-r--r--drivers/block/loop.h94
1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/block/loop.h b/drivers/block/loop.h
new file mode 100644
index 000000000..af75a5ee4
--- /dev/null
+++ b/drivers/block/loop.h
@@ -0,0 +1,94 @@
+/*
+ * 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/kthread.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;
+ atomic_t 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;
+ void *key_data;
+
+ gfp_t old_gfp_mask;
+
+ spinlock_t lo_lock;
+ int lo_state;
+ struct kthread_worker worker;
+ struct task_struct *worker_task;
+ bool use_dio;
+ bool sysfs_inited;
+
+ struct request_queue *lo_queue;
+ struct blk_mq_tag_set tag_set;
+ struct gendisk *lo_disk;
+};
+
+struct loop_cmd {
+ struct kthread_work work;
+ bool use_aio; /* use AIO interface to handle I/O */
+ atomic_t ref; /* only for aio */
+ long ret;
+ struct kiocb iocb;
+ struct bio_vec *bvec;
+ struct cgroup_subsys_state *css;
+};
+
+/* 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