Move the source code of all xloop components to the common 'src' directory

1 files changed, 0 insertions, 2245 deletions

diff --git a/kernel/xloop_main.c b/kernel/xloop_main.c
deleted file mode 100644
index a3e20a6..0000000
--- a/kernel/xloop_main.c
+++ /dev/null
@@ -1,2245 +0,0 @@
-/*
- * xloop_main.c
- *
- * 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.
- *
- * DES encryption plus some minor changes by Werner Almesberger, 30-MAY-1993
- * more DES encryption plus IDEA encryption by Nicholas J. Leon, June 20, 1996
- *
- * Modularized and updated for 1.1.16 kernel - Mitch Dsouza 28th May 1994
- * Adapted for 1.3.59 kernel - Andries Brouwer, 1 Feb 1996
- *
- * Fixed do_xloop_request() re-entrancy - Vincent.Renardias@waw.com Mar 20, 1997
- *
- * Added devfs support - Richard Gooch <rgooch@atnf.csiro.au> 16-Jan-1998
- *
- * Handle sparse backing files correctly - Kenn Humborg, Jun 28, 1998
- *
- * Loadable modules and other fixes by AK, 1998
- *
- * Make real block number available to downstream transfer functions, enables
- * CBC (and relatives) mode encryption requiring unique IVs per data block.
- * Reed H. Petty, rhp@draper.net
- *
- * Maximum number of xloop devices now dynamic via max_xloop module parameter.
- * Russell Kroll <rkroll@exploits.org> 19990701
- *
- * Maximum number of xloop devices when compiled-in now selectable by passing
- * max_xloop=<1-255> to the kernel on boot.
- * Erik I. Bolsø, <eriki@himolde.no>, Oct 31, 1999
- *
- * Completely rewrite request handling to be make_request_fn style and
- * non blocking, pushing work to a helper thread. Lots of fixes from
- * Al Viro too.
- * Jens Axboe <axboe@suse.de>, Nov 2000
- *
- * Support up to 256 xloop devices
- * Heinz Mauelshagen <mge@sistina.com>, Feb 2002
- *
- * Support for falling back on the write file operation when the address space
- * operations write_begin is not available on the backing filesystem.
- * Anton Altaparmakov, 16 Feb 2005
- *
- * Support for using file formats.
- * Manuel Bentele <development@manuel-bentele.de>, 2019
- *
- * Still To Fix:
- * - Advisory locking is ignored here.
- * - Should use an own CAP_* category instead of CAP_SYS_ADMIN
- *
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/sched.h>
-#include <linux/fs.h>
-#include <linux/file.h>
-#include <linux/stat.h>
-#include <linux/errno.h>
-#include <linux/major.h>
-#include <linux/wait.h>
-#include <linux/blkdev.h>
-#include <linux/blkpg.h>
-#include <linux/init.h>
-#include <linux/swap.h>
-#include <linux/slab.h>
-#include <linux/compat.h>
-#include <linux/suspend.h>
-#include <linux/freezer.h>
-#include <linux/mutex.h>
-#include <linux/writeback.h>
-#include <linux/completion.h>
-#include <linux/highmem.h>
-#include <linux/kthread.h>
-#include <linux/splice.h>
-#include <linux/sysfs.h>
-#include <linux/miscdevice.h>
-#include <linux/falloc.h>
-#include <linux/uio.h>
-#include <linux/ioprio.h>
-#include <linux/blk-cgroup.h>
-#include <linux/version.h>
-#ifdef CONFIG_DEBUG_FS
-#include <linux/debugfs.h>
-#endif
-
-#include "xloop_file_fmt.h"
-#include "xloop_main.h"
-
-#include <linux/uaccess.h>
-
-static DEFINE_IDR(xloop_index_idr);
-static DEFINE_MUTEX(xloop_ctl_mutex);
-
-static int max_part;
-static int part_shift;
-
-struct device *xloop_device_to_dev(struct xloop_device *xlo)
-{
-	return disk_to_dev(xlo->xlo_disk);
-}
-EXPORT_SYMBOL(xloop_device_to_dev);
-
-static int transfer_xor(struct xloop_device *xlo, int cmd,
-			struct page *raw_page, unsigned raw_off,
-			struct page *xloop_page, unsigned xloop_off,
-			int size, sector_t real_block)
-{
-	char *raw_buf = kmap_atomic(raw_page) + raw_off;
-	char *xloop_buf = kmap_atomic(xloop_page) + xloop_off;
-	char *in, *out, *key;
-	int i, keysize;
-
-	if (cmd == READ) {
-		in = raw_buf;
-		out = xloop_buf;
-	} else {
-		in = xloop_buf;
-		out = raw_buf;
-	}
-
-	key = xlo->xlo_encrypt_key;
-	keysize = xlo->xlo_encrypt_key_size;
-	for (i = 0; i < size; i++)
-		*out++ = *in++ ^ key[(i & 511) % keysize];
-
-	kunmap_atomic(xloop_buf);
-	kunmap_atomic(raw_buf);
-	cond_resched();
-	return 0;
-}
-
-static int xor_init(struct xloop_device *xlo, const struct xloop_info64 *info)
-{
-	if (unlikely(info->xlo_encrypt_key_size <= 0))
-		return -EINVAL;
-	return 0;
-}
-
-static struct xloop_func_table none_funcs = {
-	.number = XLO_CRYPT_NONE,
-}; 
-
-static struct xloop_func_table xor_funcs = {
-	.number = XLO_CRYPT_XOR,
-	.transfer = transfer_xor,
-	.init = xor_init
-}; 
-
-/* xfer_funcs[0] is special - its release function is never called */
-static struct xloop_func_table *xfer_funcs[MAX_XLO_CRYPT] = {
-	&none_funcs,
-	&xor_funcs
-};
-
-static loff_t get_xloop_size(struct xloop_device *xlo, struct file *file)
-{
-	return xloop_file_fmt_sector_size(xlo->xlo_fmt, file, xlo->xlo_offset,
-				xlo->xlo_sizelimit);
-}
-
-static void __xloop_update_dio(struct xloop_device *xlo, bool dio)
-{
-	struct file *file = xlo->xlo_backing_file;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
-	unsigned short sb_bsize = 0;
-	unsigned dio_align = 0;
-	bool use_dio;
-
-	if (inode->i_sb->s_bdev) {
-		sb_bsize = bdev_logical_block_size(inode->i_sb->s_bdev);
-		dio_align = sb_bsize - 1;
-	}
-
-	/*
-	 * We support direct I/O only if xlo_offset is aligned with the
-	 * logical I/O size of backing device, and the logical block
-	 * size of xloop is bigger than the backing device's and the xloop
-	 * needn't transform transfer.
-	 *
-	 * TODO: the above condition may be loosed in the future, and
-	 * direct I/O may be switched runtime at that time because most
-	 * of requests in sane applications should be PAGE_SIZE aligned
-	 */
-	if (dio) {
-		if (queue_logical_block_size(xlo->xlo_queue) >= sb_bsize &&
-				!(xlo->xlo_offset & dio_align) &&
-				mapping->a_ops->direct_IO &&
-				!xlo->transfer)
-			use_dio = true;
-		else
-			use_dio = false;
-	} else {
-		use_dio = false;
-	}
-
-	if (xlo->use_dio == use_dio)
-		return;
-
-	/* flush dirty pages before changing direct IO */
-	xloop_file_fmt_flush(xlo->xlo_fmt);
-
-	/*
-	 * The flag of XLO_FLAGS_DIRECT_IO is handled similarly with
-	 * XLO_FLAGS_READ_ONLY, both are set from kernel, and losetup
-	 * will get updated by ioctl(XLOOP_GET_STATUS)
-	 */
-	if (xlo->xlo_state == Xlo_bound)
-		blk_mq_freeze_queue(xlo->xlo_queue);
-	xlo->use_dio = use_dio;
-	if (use_dio) {
-		blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, xlo->xlo_queue);
-		xlo->xlo_flags |= XLO_FLAGS_DIRECT_IO;
-	} else {
-		blk_queue_flag_set(QUEUE_FLAG_NOMERGES, xlo->xlo_queue);
-		xlo->xlo_flags &= ~XLO_FLAGS_DIRECT_IO;
-	}
-	if (xlo->xlo_state == Xlo_bound)
-		blk_mq_unfreeze_queue(xlo->xlo_queue);
-}
-
-/**
- * xloop_validate_block_size() - validates the passed in block size
- * @bsize: size to validate
- */
-static int
-xloop_validate_block_size(unsigned short bsize)
-{
-	if (bsize < 512 || bsize > PAGE_SIZE || !is_power_of_2(bsize))
-		return -EINVAL;
-
-	return 0;
-}
-
-/**
- * xloop_set_size() - sets device size and notifies userspace
- * @xlo: struct xloop_device to set the size for
- * @size: new size of the xloop device
- *
- * Callers must validate that the size passed into this function fits into
- * a sector_t, eg using xloop_validate_size()
- */
-static void xloop_set_size(struct xloop_device *xlo, loff_t size)
-{
-	struct block_device *bdev = xlo->xlo_device;
-#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 7, 0)
-	sector_t capacity;
-#endif
-
-	bd_set_size(bdev, size << SECTOR_SHIFT);
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 7, 0)
-	set_capacity_revalidate_and_notify(xlo->xlo_disk, size, false);
-#else
-	capacity = get_capacity(xlo->xlo_disk);
-    set_capacity(xlo->xlo_disk, size);
-    if (capacity != size && capacity != 0 && size != 0) {
-        char *envp[] = { "RESIZE=1", NULL };
-        kobject_uevent_env(&disk_to_dev(xlo->xlo_disk)->kobj, KOBJ_CHANGE, 
-			envp);
-    }
-#endif
-}
-
-static void xlo_complete_rq(struct request *rq)
-{
-	struct xloop_cmd *cmd = blk_mq_rq_to_pdu(rq);
-	blk_status_t ret = BLK_STS_OK;
-
-	if (!cmd->use_aio || cmd->ret < 0 || cmd->ret == blk_rq_bytes(rq) ||
-	    req_op(rq) != REQ_OP_READ) {
-		if (cmd->ret < 0)
-			ret = errno_to_blk_status(cmd->ret);
-		goto end_io;
-	}
-
-	/*
-	 * Short READ - if we got some data, advance our request and
-	 * retry it. If we got no data, end the rest with EIO.
-	 */
-	if (cmd->ret) {
-		blk_update_request(rq, BLK_STS_OK, cmd->ret);
-		cmd->ret = 0;
-		blk_mq_requeue_request(rq, true);
-	} else {
-		if (cmd->use_aio) {
-			struct bio *bio = rq->bio;
-
-			while (bio) {
-				zero_fill_bio(bio);
-				bio = bio->bi_next;
-			}
-		}
-		ret = BLK_STS_IOERR;
-end_io:
-		blk_mq_end_request(rq, ret);
-	}
-}
-
-static int do_req_filebacked(struct xloop_device *xlo, struct request *rq)
-{
-	struct xloop_cmd *cmd = blk_mq_rq_to_pdu(rq);
-
-	/*
-	 * xlo_write_simple and xlo_read_simple should have been covered
-	 * by io submit style function like xlo_rw_aio(), one blocker
-	 * is that xlo_read_simple() need to call flush_dcache_page after
-	 * the page is written from kernel, and it isn't easy to handle
-	 * this in io submit style function which submits all segments
-	 * of the req at one time. And direct read IO doesn't need to
-	 * run flush_dcache_page().
-	 */
-	switch (req_op(rq)) {
-	case REQ_OP_FLUSH:
-		return xloop_file_fmt_flush(xlo->xlo_fmt);
-	case REQ_OP_WRITE_ZEROES:
-		return xloop_file_fmt_write_zeros(xlo->xlo_fmt, rq);
-	case REQ_OP_DISCARD:
-		return xloop_file_fmt_discard(xlo->xlo_fmt, rq);
-	case REQ_OP_WRITE:
-		if (cmd->use_aio)
-			return xloop_file_fmt_write_aio(xlo->xlo_fmt, rq);
-		else
-			return xloop_file_fmt_write(xlo->xlo_fmt, rq);
-	case REQ_OP_READ:
-		if (cmd->use_aio)
-			return xloop_file_fmt_read_aio(xlo->xlo_fmt, rq);
-		else
-			return xloop_file_fmt_read(xlo->xlo_fmt, rq);
-	default:
-		WARN_ON_ONCE(1);
-		return -EIO;
-	}
-}
-
-static inline void xloop_update_dio(struct xloop_device *xlo)
-{
-	__xloop_update_dio(xlo, (xlo->xlo_backing_file->f_flags & O_DIRECT) |
-				xlo->use_dio);
-}
-
-static void xloop_reread_partitions(struct xloop_device *xlo,
-				   struct block_device *bdev)
-{
-	int rc;
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 5, 0)
-	mutex_lock(&bdev->bd_mutex);
-	rc = bdev_disk_changed(bdev, false);
-	mutex_unlock(&bdev->bd_mutex);
-#else
-	rc = blkdev_reread_part(bdev);
-#endif
-	if (rc)
-		dev_warn(xloop_device_to_dev(xlo), "partition scan failed (rc=%d)\n",
-			rc);
-}
-
-static inline int is_xloop_device(struct file *file)
-{
-	struct inode *i = file->f_mapping->host;
-
-	return i && S_ISBLK(i->i_mode) && MAJOR(i->i_rdev) == XLOOP_MAJOR;
-}
-
-static int xloop_validate_file(struct file *file, struct block_device *bdev)
-{
-	struct inode	*inode = file->f_mapping->host;
-	struct file	*f = file;
-
-	/* Avoid recursion */
-	while (is_xloop_device(f)) {
-		struct xloop_device *l;
-
-		if (f->f_mapping->host->i_bdev == bdev)
-			return -EBADF;
-
-		l = f->f_mapping->host->i_bdev->bd_disk->private_data;
-		if (l->xlo_state != Xlo_bound) {
-			return -EINVAL;
-		}
-		f = l->xlo_backing_file;
-	}
-	if (!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode))
-		return -EINVAL;
-	return 0;
-}
-
-/*
- * xloop_change_fd switched the backing store of a xloopback device to
- * a new file. This is useful for operating system installers to free up
- * the original file and in High Availability environments to switch to
- * an alternative location for the content in case of server meltdown.
- * This can only work if the xloop device is used read-only, and if the
- * new backing store is the same size and type as the old backing store.
- */
-static int xloop_change_fd(struct xloop_device *xlo, struct block_device *bdev,
-			  unsigned int arg)
-{
-	struct file	*file = NULL, *old_file;
-	int		error;
-	bool		partscan;
-
-	error = mutex_lock_killable(&xloop_ctl_mutex);
-	if (error)
-		return error;
-	error = -ENXIO;
-	if (xlo->xlo_state != Xlo_bound)
-		goto out_err;
-
-	/* the xloop device has to be read-only */
-	error = -EINVAL;
-	if (!(xlo->xlo_flags & XLO_FLAGS_READ_ONLY))
-		goto out_err;
-
-	error = -EBADF;
-	file = fget(arg);
-	if (!file)
-		goto out_err;
-
-	error = xloop_validate_file(file, bdev);
-	if (error)
-		goto out_err;
-
-	old_file = xlo->xlo_backing_file;
-
-	error = -EINVAL;
-
-	/* size of the new backing store needs to be the same */
-	if (get_xloop_size(xlo, file) != get_xloop_size(xlo, old_file))
-		goto out_err;
-
-	/* and ... switch */
-	blk_mq_freeze_queue(xlo->xlo_queue);
-	mapping_set_gfp_mask(old_file->f_mapping, xlo->old_gfp_mask);
-	xlo->xlo_backing_file = file;
-	xlo->old_gfp_mask = mapping_gfp_mask(file->f_mapping);
-	mapping_set_gfp_mask(file->f_mapping,
-			     xlo->old_gfp_mask & ~(__GFP_IO|__GFP_FS));
-	xloop_update_dio(xlo);
-	blk_mq_unfreeze_queue(xlo->xlo_queue);
-	partscan = xlo->xlo_flags & XLO_FLAGS_PARTSCAN;
-	mutex_unlock(&xloop_ctl_mutex);
-	/*
-	 * We must drop file reference outside of xloop_ctl_mutex as dropping
-	 * the file ref can take bd_mutex which creates circular locking
-	 * dependency.
-	 */
-	fput(old_file);
-	if (partscan)
-		xloop_reread_partitions(xlo, bdev);
-	return 0;
-
-out_err:
-	mutex_unlock(&xloop_ctl_mutex);
-	if (file)
-		fput(file);
-	return error;
-}
-
-/* xloop sysfs attributes */
-
-static ssize_t xloop_attr_show(struct device *dev, char *page,
-			      ssize_t (*callback)(struct xloop_device *, char *))
-{
-	struct gendisk *disk = dev_to_disk(dev);
-	struct xloop_device *xlo = disk->private_data;
-
-	return callback(xlo, page);
-}
-
-#define XLOOP_ATTR_RO(_name)						\
-static ssize_t xloop_attr_##_name##_show(struct xloop_device *, char *);	\
-static ssize_t xloop_attr_do_show_##_name(struct device *d,		\
-				struct device_attribute *attr, char *b)	\
-{									\
-	return xloop_attr_show(d, b, xloop_attr_##_name##_show);		\
-}									\
-static struct device_attribute xloop_attr_##_name =			\
-	__ATTR(_name, 0444, xloop_attr_do_show_##_name, NULL);
-
-static ssize_t xloop_attr_backing_file_show(struct xloop_device *xlo, char *buf)
-{
-	ssize_t ret;
-	char *p = NULL;
-
-	spin_lock_irq(&xlo->xlo_lock);
-	if (xlo->xlo_backing_file)
-		p = file_path(xlo->xlo_backing_file, buf, PAGE_SIZE - 1);
-	spin_unlock_irq(&xlo->xlo_lock);
-
-	if (IS_ERR_OR_NULL(p))
-		ret = PTR_ERR(p);
-	else {
-		ret = strlen(p);
-		memmove(buf, p, ret);
-		buf[ret++] = '\n';
-		buf[ret] = 0;
-	}
-
-	return ret;
-}
-
-static ssize_t xloop_attr_file_fmt_type_show(struct xloop_device *xlo,
-				char *buf)
-{
-	ssize_t len = 0;
-
-	len = xloop_file_fmt_print_type(xlo->xlo_fmt->file_fmt_type, buf);
-	len += sprintf(buf + len, "\n");
-
-	return len;
-}
-
-static ssize_t xloop_attr_offset_show(struct xloop_device *xlo, char *buf)
-{
-	return sprintf(buf, "%llu\n", (unsigned long long)xlo->xlo_offset);
-}
-
-static ssize_t xloop_attr_sizelimit_show(struct xloop_device *xlo, char *buf)
-{
-	return sprintf(buf, "%llu\n", (unsigned long long)xlo->xlo_sizelimit);
-}
-
-static ssize_t xloop_attr_autoclear_show(struct xloop_device *xlo, char *buf)
-{
-	int autoclear = (xlo->xlo_flags & XLO_FLAGS_AUTOCLEAR);
-
-	return sprintf(buf, "%s\n", autoclear ? "1" : "0");
-}
-
-static ssize_t xloop_attr_partscan_show(struct xloop_device *xlo, char *buf)
-{
-	int partscan = (xlo->xlo_flags & XLO_FLAGS_PARTSCAN);
-
-	return sprintf(buf, "%s\n", partscan ? "1" : "0");
-}
-
-static ssize_t xloop_attr_dio_show(struct xloop_device *xlo, char *buf)
-{
-	int dio = (xlo->xlo_flags & XLO_FLAGS_DIRECT_IO);
-
-	return sprintf(buf, "%s\n", dio ? "1" : "0");
-}
-
-XLOOP_ATTR_RO(backing_file);
-XLOOP_ATTR_RO(file_fmt_type);
-XLOOP_ATTR_RO(offset);
-XLOOP_ATTR_RO(sizelimit);
-XLOOP_ATTR_RO(autoclear);
-XLOOP_ATTR_RO(partscan);
-XLOOP_ATTR_RO(dio);
-
-static struct attribute *xloop_attrs[] = {
-	&xloop_attr_backing_file.attr,
-	&xloop_attr_file_fmt_type.attr,
-	&xloop_attr_offset.attr,
-	&xloop_attr_sizelimit.attr,
-	&xloop_attr_autoclear.attr,
-	&xloop_attr_partscan.attr,
-	&xloop_attr_dio.attr,
-	NULL,
-};
-
-static struct attribute_group xloop_attribute_group = {
-	.name = "xloop",
-	.attrs= xloop_attrs,
-};
-
-static void xloop_sysfs_init(struct xloop_device *xlo)
-{
-	xlo->sysfs_inited = !sysfs_create_group(&disk_to_dev(xlo->xlo_disk)->kobj,
-						&xloop_attribute_group);
-}
-
-static void xloop_sysfs_exit(struct xloop_device *xlo)
-{
-	if (xlo->sysfs_inited)
-		sysfs_remove_group(&disk_to_dev(xlo->xlo_disk)->kobj,
-				   &xloop_attribute_group);
-}
-
-static void xloop_config_discard(struct xloop_device *xlo)
-{
-	struct file *file = xlo->xlo_backing_file;
-	struct inode *inode = file->f_mapping->host;
-	struct request_queue *q = xlo->xlo_queue;
-	u32 granularity, max_discard_sectors;
-
-	/*
-	 * If the backing device is a block device, mirror its zeroing
-	 * capability. Set the discard sectors to the block device's zeroing
-	 * capabilities because xloop discards result in blkdev_issue_zeroout(),
-	 * not blkdev_issue_discard(). This maintains consistent behavior with
-	 * file-backed xloop devices: discarded regions read back as zero.
-	 */
-	if (S_ISBLK(inode->i_mode) && !xlo->xlo_encrypt_key_size) {
-		struct request_queue *backingq;
-
-		backingq = bdev_get_queue(inode->i_bdev);
-
-		max_discard_sectors = backingq->limits.max_write_zeroes_sectors;
-		granularity = backingq->limits.discard_granularity ?:
-			queue_physical_block_size(backingq);
-
-	/*
-	 * We use punch hole to reclaim the free space used by the
-	 * image a.k.a. discard. However we do not support discard if
-	 * encryption is enabled, because it may give an attacker
-	 * useful information.
-	 */
-	} else if (!file->f_op->fallocate || xlo->xlo_encrypt_key_size) {
-		max_discard_sectors = 0;
-		granularity = 0;
-
-	} else {
-		max_discard_sectors = UINT_MAX >> 9;
-		granularity = inode->i_sb->s_blocksize;
-	}
-
-	if (max_discard_sectors) {
-		q->limits.discard_granularity = granularity;
-		blk_queue_max_discard_sectors(q, max_discard_sectors);
-		blk_queue_max_write_zeroes_sectors(q, max_discard_sectors);
-		blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
-	} else {
-		q->limits.discard_granularity = 0;
-		blk_queue_max_discard_sectors(q, 0);
-		blk_queue_max_write_zeroes_sectors(q, 0);
-		blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q);
-	}
-	q->limits.discard_alignment = 0;
-}
-
-static void xloop_unprepare_queue(struct xloop_device *xlo)
-{
-	kthread_flush_worker(&xlo->worker);
-	kthread_stop(xlo->worker_task);
-}
-
-static int xloop_kthread_worker_fn(void *worker_ptr)
-{
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
-	current->flags |= PF_LOCAL_THROTTLE | PF_MEMALLOC_NOIO;
-#else
-	current->flags |= PF_LESS_THROTTLE | PF_MEMALLOC_NOIO;
-#endif
-	return kthread_worker_fn(worker_ptr);
-}
-
-static int xloop_prepare_queue(struct xloop_device *xlo)
-{
-	kthread_init_worker(&xlo->worker);
-	xlo->worker_task = kthread_run(xloop_kthread_worker_fn,
-			&xlo->worker, "xloop%d", xlo->xlo_number);
-	if (IS_ERR(xlo->worker_task))
-		return -ENOMEM;
-	set_user_nice(xlo->worker_task, MIN_NICE);
-	return 0;
-}
-
-static void xloop_update_rotational(struct xloop_device *xlo)
-{
-	struct file *file = xlo->xlo_backing_file;
-	struct inode *file_inode = file->f_mapping->host;
-	struct block_device *file_bdev = file_inode->i_sb->s_bdev;
-	struct request_queue *q = xlo->xlo_queue;
-	bool nonrot = true;
-
-	/* not all filesystems (e.g. tmpfs) have a sb->s_bdev */
-	if (file_bdev)
-		nonrot = blk_queue_nonrot(bdev_get_queue(file_bdev));
-
-	if (nonrot)
-		blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
-	else
-		blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
-}
-
-static int
-xloop_release_xfer(struct xloop_device *xlo)
-{
-	int err = 0;
-	struct xloop_func_table *xfer = xlo->xlo_encryption;
-
-	if (xfer) {
-		if (xfer->release)
-			err = xfer->release(xlo);
-		xlo->transfer = NULL;
-		xlo->xlo_encryption = NULL;
-		module_put(xfer->owner);
-	}
-	return err;
-}
-
-static int
-xloop_init_xfer(struct xloop_device *xlo, struct xloop_func_table *xfer,
-	       const struct xloop_info64 *i)
-{
-	int err = 0;
-
-	if (xfer) {
-		struct module *owner = xfer->owner;
-
-		if (!try_module_get(owner))
-			return -EINVAL;
-		if (xfer->init)
-			err = xfer->init(xlo, i);
-		if (err)
-			module_put(owner);
-		else
-			xlo->xlo_encryption = xfer;
-	}
-	return err;
-}
-
-/**
- * xloop_set_status_from_info - configure device from xloop_info
- * @xlo: struct xloop_device to configure
- * @info: struct xloop_info64 to configure the device with
- *
- * Configures the xloop device parameters according to the passed
- * in xloop_info64 configuration.
- */
-static int
-xloop_set_status_from_info(struct xloop_device *xlo,
-			  const struct xloop_info64 *info)
-{
-	int err;
-	struct xloop_func_table *xfer;
-	kuid_t uid = current_uid();
-
-	if ((unsigned int) info->xlo_encrypt_key_size > XLO_KEY_SIZE)
-		return -EINVAL;
-
-	err = xloop_release_xfer(xlo);
-	if (err)
-		return err;
-
-	if (info->xlo_encrypt_type) {
-		unsigned int type = info->xlo_encrypt_type;
-
-		if (type >= MAX_XLO_CRYPT)
-			return -EINVAL;
-		xfer = xfer_funcs[type];
-		if (xfer == NULL)
-			return -EINVAL;
-	} else
-		xfer = NULL;
-
-	err = xloop_init_xfer(xlo, xfer, info);
-	if (err)
-		return err;
-
-	xlo->xlo_offset = info->xlo_offset;
-	xlo->xlo_sizelimit = info->xlo_sizelimit;
-	memcpy(xlo->xlo_file_name, info->xlo_file_name, XLO_NAME_SIZE);
-	memcpy(xlo->xlo_crypt_name, info->xlo_crypt_name, XLO_NAME_SIZE);
-	xlo->xlo_file_name[XLO_NAME_SIZE-1] = 0;
-	xlo->xlo_crypt_name[XLO_NAME_SIZE-1] = 0;
-
-	if (!xfer)
-		xfer = &none_funcs;
-	xlo->transfer = xfer->transfer;
-	xlo->ioctl = xfer->ioctl;
-
-	xlo->xlo_flags = info->xlo_flags;
-
-	xlo->xlo_encrypt_key_size = info->xlo_encrypt_key_size;
-	xlo->xlo_init[0] = info->xlo_init[0];
-	xlo->xlo_init[1] = info->xlo_init[1];
-	if (info->xlo_encrypt_key_size) {
-		memcpy(xlo->xlo_encrypt_key, info->xlo_encrypt_key,
-		       info->xlo_encrypt_key_size);
-		xlo->xlo_key_owner = uid;
-	}
-
-	return 0;
-}
-
-static int xloop_configure(struct xloop_device *xlo, fmode_t mode,
-			  struct block_device *bdev,
-			  const struct xloop_config *config)
-{
-	struct file	*file;
-	struct inode	*inode;
-	struct address_space *mapping;
-	struct block_device *claimed_bdev = NULL;
-	int		error;
-	loff_t		size;
-	bool		partscan;
-	unsigned short  bsize;
-
-	/* This is safe, since we have a reference from open(). */
-	__module_get(THIS_MODULE);
-
-	error = -EBADF;
-	file = fget(config->fd);
-	if (!file)
-		goto out;
-
-	/*
-	 * If we don't hold exclusive handle for the device, upgrade to it
-	 * here to avoid changing device under exclusive owner.
-	 */
-	if (!(mode & FMODE_EXCL)) {
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 9, 0)
-		claimed_bdev = bdev->bd_contains;
-		error = bd_prepare_to_claim(bdev, claimed_bdev, xloop_configure);
-		if (error)
-			goto out_putf;
-#else
-		claimed_bdev = bd_start_claiming(bdev, xloop_configure);
-		if (IS_ERR(claimed_bdev)) {
-			error = PTR_ERR(claimed_bdev);
-			goto out_putf;
-		}
-#endif
-	}
-
-	error = mutex_lock_killable(&xloop_ctl_mutex);
-	if (error)
-		goto out_bdev;
-
-	error = -EBUSY;
-	if (xlo->xlo_state != Xlo_unbound)
-		goto out_unlock;
-
-	error = xloop_validate_file(file, bdev);
-	if (error)
-		goto out_unlock;
-
-	mapping = file->f_mapping;
-	inode = mapping->host;
-
-	if ((config->info.xlo_flags & ~XLOOP_CONFIGURE_SETTABLE_FLAGS) != 0) {
-		error = -EINVAL;
-		goto out_unlock;
-	}
-
-	if (config->block_size) {
-		error = xloop_validate_block_size(config->block_size);
-		if (error)
-			goto out_unlock;
-	}
-
-	error = xloop_set_status_from_info(xlo, &config->info);
-	if (error)
-		goto out_unlock;
-
-	if (!(file->f_mode & FMODE_WRITE) || !(mode & FMODE_WRITE) ||
-	    !file->f_op->write_iter)
-		xlo->xlo_flags |= XLO_FLAGS_READ_ONLY;
-
-	error = xloop_prepare_queue(xlo);
-	if (error)
-		goto out_unlock;
-
-	error = xloop_file_fmt_init(xlo->xlo_fmt,
-				config->info.xlo_file_fmt_type);
-	if (error)
-		goto out_unlock;
-
-	set_device_ro(bdev, (xlo->xlo_flags & XLO_FLAGS_READ_ONLY) != 0);
-
-	xlo->use_dio = xlo->xlo_flags & XLO_FLAGS_DIRECT_IO;
-	xlo->xlo_device = bdev;
-	xlo->xlo_backing_file = file;
-	xlo->old_gfp_mask = mapping_gfp_mask(mapping);
-	mapping_set_gfp_mask(mapping, xlo->old_gfp_mask & ~(__GFP_IO|__GFP_FS));
-
-	if (!(xlo->xlo_flags & XLO_FLAGS_READ_ONLY) && file->f_op->fsync)
-		blk_queue_write_cache(xlo->xlo_queue, true, false);
-
-	if (config->block_size)
-		bsize = config->block_size;
-	else if ((xlo->xlo_backing_file->f_flags & O_DIRECT) && inode->i_sb->s_bdev)
-		/* In case of direct I/O, match underlying block size */
-		bsize = bdev_logical_block_size(inode->i_sb->s_bdev);
-	else
-		bsize = 512;
-
-	blk_queue_logical_block_size(xlo->xlo_queue, bsize);
-	blk_queue_physical_block_size(xlo->xlo_queue, bsize);
-	blk_queue_io_min(xlo->xlo_queue, bsize);
-
-	xloop_update_rotational(xlo);
-	xloop_update_dio(xlo);
-	xloop_sysfs_init(xlo);
-
-	size = get_xloop_size(xlo, file);
-	xloop_set_size(xlo, size);
-
-	set_blocksize(bdev, S_ISBLK(inode->i_mode) ?
-		      block_size(inode->i_bdev) : PAGE_SIZE);
-
-	xlo->xlo_state = Xlo_bound;
-	if (part_shift)
-		xlo->xlo_flags |= XLO_FLAGS_PARTSCAN;
-	partscan = xlo->xlo_flags & XLO_FLAGS_PARTSCAN;
-	if (partscan)
-		xlo->xlo_disk->flags &= ~GENHD_FL_NO_PART_SCAN;
-
-	/* Grab the block_device to prevent its destruction after we
-	 * put /dev/xloopXX inode. Later in __xloop_clr_fd() we bdput(bdev).
-	 */
-	bdgrab(bdev);
-	mutex_unlock(&xloop_ctl_mutex);
-	if (partscan)
-		xloop_reread_partitions(xlo, bdev);
-	if (claimed_bdev)
-		bd_abort_claiming(bdev, claimed_bdev, xloop_configure);
-	return 0;
-
-out_unlock:
-	mutex_unlock(&xloop_ctl_mutex);
-out_bdev:
-	if (claimed_bdev)
-		bd_abort_claiming(bdev, claimed_bdev, xloop_configure);
-out_putf:
-	fput(file);
-out:
-	/* This is safe: open() is still holding a reference. */
-	module_put(THIS_MODULE);
-	return error;
-}
-
-static int __xloop_clr_fd(struct xloop_device *xlo, bool release)
-{
-	struct file *filp = NULL;
-	gfp_t gfp = xlo->old_gfp_mask;
-	struct block_device *bdev = xlo->xlo_device;
-	int err = 0;
-	bool partscan = false;
-	int xlo_number;
-
-	mutex_lock(&xloop_ctl_mutex);
-	if (WARN_ON_ONCE(xlo->xlo_state != Xlo_rundown)) {
-		err = -ENXIO;
-		goto out_unlock;
-	}
-
-	filp = xlo->xlo_backing_file;
-	if (filp == NULL) {
-		err = -EINVAL;
-		goto out_unlock;
-	}
-
-	/* freeze request queue during the transition */
-	blk_mq_freeze_queue(xlo->xlo_queue);
-
-	xloop_file_fmt_exit(xlo->xlo_fmt);
-
-	spin_lock_irq(&xlo->xlo_lock);
-	xlo->xlo_backing_file = NULL;
-	spin_unlock_irq(&xlo->xlo_lock);
-
-	xloop_release_xfer(xlo);
-	xlo->transfer = NULL;
-	xlo->ioctl = NULL;
-	xlo->xlo_device = NULL;
-	xlo->xlo_encryption = NULL;
-	xlo->xlo_offset = 0;
-	xlo->xlo_sizelimit = 0;
-	xlo->xlo_encrypt_key_size = 0;
-	memset(xlo->xlo_encrypt_key, 0, XLO_KEY_SIZE);
-	memset(xlo->xlo_crypt_name, 0, XLO_NAME_SIZE);
-	memset(xlo->xlo_file_name, 0, XLO_NAME_SIZE);
-	blk_queue_logical_block_size(xlo->xlo_queue, 512);
-	blk_queue_physical_block_size(xlo->xlo_queue, 512);
-	blk_queue_io_min(xlo->xlo_queue, 512);
-	if (bdev) {
-		bdput(bdev);
-		invalidate_bdev(bdev);
-		bdev->bd_inode->i_mapping->wb_err = 0;
-	}
-	set_capacity(xlo->xlo_disk, 0);
-	xloop_sysfs_exit(xlo);
-	if (bdev) {
-		bd_set_size(bdev, 0);
-		/* let user-space know about this change */
-		kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
-	}
-	mapping_set_gfp_mask(filp->f_mapping, gfp);
-	/* This is safe: open() is still holding a reference. */
-	module_put(THIS_MODULE);
-	blk_mq_unfreeze_queue(xlo->xlo_queue);
-
-	partscan = xlo->xlo_flags & XLO_FLAGS_PARTSCAN && bdev;
-	xlo_number = xlo->xlo_number;
-	xloop_unprepare_queue(xlo);
-out_unlock:
-	mutex_unlock(&xloop_ctl_mutex);
-	if (partscan) {
-		/*
-		 * bd_mutex has been held already in release path, so don't
-		 * acquire it if this function is called in such case.
-		 *
-		 * If the reread partition isn't from release path, xlo_refcnt
-		 * must be at least one and it can only become zero when the
-		 * current holder is released.
-		 */
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 5, 0)
-		if (!release)
-			mutex_lock(&bdev->bd_mutex);
-		err = bdev_disk_changed(bdev, false);
-#else
-		err = blkdev_reread_part(bdev);
-#endif
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 5, 0)
-		if (!release)
-			mutex_unlock(&bdev->bd_mutex);
-#endif
-		if (err)
-			dev_warn(xloop_device_to_dev(xlo), "partition scan failed "
-				"(rc=%d)\n", err);
-		/* Device is gone, no point in returning error */
-		err = 0;
-	}
-
-	/*
-	 * xlo->xlo_state is set to Xlo_unbound here after above partscan has
-	 * finished.
-	 *
-	 * There cannot be anybody else entering __xloop_clr_fd() as
-	 * xlo->xlo_backing_file is already cleared and Xlo_rundown state
-	 * protects us from all the other places trying to change the 'xlo'
-	 * device.
-	 */
-	mutex_lock(&xloop_ctl_mutex);
-	xlo->xlo_flags = 0;
-	if (!part_shift)
-		xlo->xlo_disk->flags |= GENHD_FL_NO_PART_SCAN;
-	xlo->xlo_state = Xlo_unbound;
-	mutex_unlock(&xloop_ctl_mutex);
-
-	/*
-	 * Need not hold xloop_ctl_mutex to fput backing file.
-	 * Calling fput holding xloop_ctl_mutex triggers a circular
-	 * lock dependency possibility warning as fput can take
-	 * bd_mutex which is usually taken before xloop_ctl_mutex.
-	 */
-	if (filp)
-		fput(filp);
-	return err;
-}
-
-static int xloop_clr_fd(struct xloop_device *xlo)
-{
-	int err;
-
-	err = mutex_lock_killable(&xloop_ctl_mutex);
-	if (err)
-		return err;
-	if (xlo->xlo_state != Xlo_bound) {
-		mutex_unlock(&xloop_ctl_mutex);
-		return -ENXIO;
-	}
-	/*
-	 * If we've explicitly asked to tear down the xloop device,
-	 * and it has an elevated reference count, set it for auto-teardown when
-	 * the last reference goes away. This stops $!~#$@ udev from
-	 * preventing teardown because it decided that it needs to run blkid on
-	 * the xloopback device whenever they appear. xfstests is notorious for
-	 * failing tests because blkid via udev races with a losetup
-	 * <dev>/do something like mkfs/losetup -d <dev> causing the losetup -d
-	 * command to fail with EBUSY.
-	 */
-	if (atomic_read(&xlo->xlo_refcnt) > 1) {
-		xlo->xlo_flags |= XLO_FLAGS_AUTOCLEAR;
-		mutex_unlock(&xloop_ctl_mutex);
-		return 0;
-	}
-	xlo->xlo_state = Xlo_rundown;
-	mutex_unlock(&xloop_ctl_mutex);
-
-	return __xloop_clr_fd(xlo, false);
-}
-
-static int
-xloop_set_status(struct xloop_device *xlo, const struct xloop_info64 *info)
-{
-	int err;
-	struct block_device *bdev;
-	kuid_t uid = current_uid();
-	int prev_xlo_flags;
-	bool partscan = false;
-	bool size_changed = false;
-
-	err = mutex_lock_killable(&xloop_ctl_mutex);
-	if (err)
-		return err;
-	if (xlo->xlo_encrypt_key_size &&
-	    !uid_eq(xlo->xlo_key_owner, uid) &&
-	    !capable(CAP_SYS_ADMIN)) {
-		err = -EPERM;
-		goto out_unlock;
-	}
-	if (xlo->xlo_state != Xlo_bound) {
-		err = -ENXIO;
-		goto out_unlock;
-	}
-
-	if (xlo->xlo_offset != info->xlo_offset ||
-	    xlo->xlo_sizelimit != info->xlo_sizelimit) {
-		size_changed = true;
-		sync_blockdev(xlo->xlo_device);
-		invalidate_bdev(xlo->xlo_device);
-	}
-
-	/* I/O need to be drained during transfer transition */
-	blk_mq_freeze_queue(xlo->xlo_queue);
-
-	if (size_changed && xlo->xlo_device->bd_inode->i_mapping->nrpages) {
-		/* If any pages were dirtied after invalidate_bdev(), try again */
-		err = -EAGAIN;
-		dev_warn(xloop_device_to_dev(xlo), "xloop device has still dirty "
-			"pages (nrpages=%lu)\n",
-			xlo->xlo_device->bd_inode->i_mapping->nrpages);
-		goto out_unfreeze;
-	}
-
-	prev_xlo_flags = xlo->xlo_flags;
-
-	err = xloop_set_status_from_info(xlo, info);
-	if (err)
-		goto out_unfreeze;
-
-	/* Mask out flags that can't be set using XLOOP_SET_STATUS. */
-	xlo->xlo_flags &= XLOOP_SET_STATUS_SETTABLE_FLAGS;
-	/* For those flags, use the previous values instead */
-	xlo->xlo_flags |= prev_xlo_flags & ~XLOOP_SET_STATUS_SETTABLE_FLAGS;
-	/* For flags that can't be cleared, use previous values too */
-	xlo->xlo_flags |= prev_xlo_flags & ~XLOOP_SET_STATUS_CLEARABLE_FLAGS;
-
-	if (xlo->xlo_fmt->file_fmt_type != info->xlo_file_fmt_type) {
-		/* xloop file format has changed, so change file format driver */
-		err = xloop_file_fmt_change(xlo->xlo_fmt, info->xlo_file_fmt_type);
-		if (err)
-			goto out_unfreeze;
-
-		/* After change of the file format, recalculate the capacity of
-		 * the loop device. */
-		size_changed = true;
-	}
-
-	if (size_changed) {
-		loff_t new_size = get_xloop_size(xlo, xlo->xlo_backing_file);
-		xloop_set_size(xlo, new_size);
-	}
-
-	xloop_config_discard(xlo);
-
-	/* update dio if xlo_offset or transfer is changed */
-	__xloop_update_dio(xlo, xlo->use_dio);
-
-out_unfreeze:
-	blk_mq_unfreeze_queue(xlo->xlo_queue);
-
-	if (!err && (xlo->xlo_flags & XLO_FLAGS_PARTSCAN) &&
-	     !(prev_xlo_flags & XLO_FLAGS_PARTSCAN)) {
-		xlo->xlo_disk->flags &= ~GENHD_FL_NO_PART_SCAN;
-		bdev = xlo->xlo_device;
-		partscan = true;
-	}
-out_unlock:
-	mutex_unlock(&xloop_ctl_mutex);
-	if (partscan)
-		xloop_reread_partitions(xlo, bdev);
-
-	return err;
-}
-
-static int
-xloop_get_status(struct xloop_device *xlo, struct xloop_info64 *info)
-{
-	struct path path;
-	struct kstat stat;
-	int ret;
-
-	ret = mutex_lock_killable(&xloop_ctl_mutex);
-	if (ret)
-		return ret;
-	if (xlo->xlo_state != Xlo_bound) {
-		mutex_unlock(&xloop_ctl_mutex);
-		return -ENXIO;
-	}
-
-	memset(info, 0, sizeof(*info));
-	info->xlo_number = xlo->xlo_number;
-	info->xlo_offset = xlo->xlo_offset;
-	info->xlo_sizelimit = xlo->xlo_sizelimit;
-	info->xlo_flags = xlo->xlo_flags;
-	memcpy(info->xlo_file_name, xlo->xlo_file_name, XLO_NAME_SIZE);
-	memcpy(info->xlo_crypt_name, xlo->xlo_crypt_name, XLO_NAME_SIZE);
-	info->xlo_encrypt_type =
-		xlo->xlo_encryption ? xlo->xlo_encryption->number : 0;
-	if (xlo->xlo_encrypt_key_size && capable(CAP_SYS_ADMIN)) {
-		info->xlo_encrypt_key_size = xlo->xlo_encrypt_key_size;
-		memcpy(info->xlo_encrypt_key, xlo->xlo_encrypt_key,
-		       xlo->xlo_encrypt_key_size);
-	}
-
-	/* Drop xloop_ctl_mutex while we call into the filesystem. */
-	path = xlo->xlo_backing_file->f_path;
-	path_get(&path);
-	mutex_unlock(&xloop_ctl_mutex);
-	ret = vfs_getattr(&path, &stat, STATX_INO, AT_STATX_SYNC_AS_STAT);
-	if (!ret) {
-		info->xlo_device = huge_encode_dev(stat.dev);
-		info->xlo_inode = stat.ino;
-		info->xlo_rdevice = huge_encode_dev(stat.rdev);
-	}
-	path_put(&path);
-	return ret;
-}
-
-static void
-xloop_info64_from_old(const struct xloop_info *info, struct xloop_info64 *info64)
-{
-	memset(info64, 0, sizeof(*info64));
-	info64->xlo_number = info->xlo_number;
-	info64->xlo_device = info->xlo_device;
-	info64->xlo_inode = info->xlo_inode;
-	info64->xlo_rdevice = info->xlo_rdevice;
-	info64->xlo_offset = info->xlo_offset;
-	info64->xlo_sizelimit = 0;
-	info64->xlo_encrypt_type = info->xlo_encrypt_type;
-	info64->xlo_encrypt_key_size = info->xlo_encrypt_key_size;
-	info64->xlo_flags = info->xlo_flags;
-	info64->xlo_init[0] = info->xlo_init[0];
-	info64->xlo_init[1] = info->xlo_init[1];
-	info64->xlo_file_fmt_type = info->xlo_file_fmt_type;
-	if (info->xlo_encrypt_type == XLO_CRYPT_CRYPTOAPI)
-		memcpy(info64->xlo_crypt_name, info->xlo_name, XLO_NAME_SIZE);
-	else
-		memcpy(info64->xlo_file_name, info->xlo_name, XLO_NAME_SIZE);
-	memcpy(info64->xlo_encrypt_key, info->xlo_encrypt_key, XLO_KEY_SIZE);
-}
-
-static int
-xloop_info64_to_old(const struct xloop_info64 *info64, struct xloop_info *info)
-{
-	memset(info, 0, sizeof(*info));
-	info->xlo_number = info64->xlo_number;
-	info->xlo_device = info64->xlo_device;
-	info->xlo_inode = info64->xlo_inode;
-	info->xlo_rdevice = info64->xlo_rdevice;
-	info->xlo_offset = info64->xlo_offset;
-	info->xlo_encrypt_type = info64->xlo_encrypt_type;
-	info->xlo_encrypt_key_size = info64->xlo_encrypt_key_size;
-	info->xlo_flags = info64->xlo_flags;
-	info->xlo_init[0] = info64->xlo_init[0];
-	info->xlo_init[1] = info64->xlo_init[1];
-	info->xlo_file_fmt_type = info64->xlo_file_fmt_type;
-	if (info->xlo_encrypt_type == XLO_CRYPT_CRYPTOAPI)
-		memcpy(info->xlo_name, info64->xlo_crypt_name, XLO_NAME_SIZE);
-	else
-		memcpy(info->xlo_name, info64->xlo_file_name, XLO_NAME_SIZE);
-	memcpy(info->xlo_encrypt_key, info64->xlo_encrypt_key, XLO_KEY_SIZE);
-
-	/* error in case values were truncated */
-	if (info->xlo_device != info64->xlo_device ||
-	    info->xlo_rdevice != info64->xlo_rdevice ||
-	    info->xlo_inode != info64->xlo_inode ||
-	    info->xlo_offset != info64->xlo_offset)
-		return -EOVERFLOW;
-
-	return 0;
-}
-
-static int
-xloop_set_status_old(struct xloop_device *xlo, const struct xloop_info __user *arg)
-{
-	struct xloop_info info;
-	struct xloop_info64 info64;
-
-	if (copy_from_user(&info, arg, sizeof (struct xloop_info)))
-		return -EFAULT;
-	xloop_info64_from_old(&info, &info64);
-	return xloop_set_status(xlo, &info64);
-}
-
-static int
-xloop_set_status64(struct xloop_device *xlo, const struct xloop_info64 __user *arg)
-{
-	struct xloop_info64 info64;
-
-	if (copy_from_user(&info64, arg, sizeof (struct xloop_info64)))
-		return -EFAULT;
-	return xloop_set_status(xlo, &info64);
-}
-
-static int
-xloop_get_status_old(struct xloop_device *xlo, struct xloop_info __user *arg) {
-	struct xloop_info info;
-	struct xloop_info64 info64;
-	int err;
-
-	if (!arg)
-		return -EINVAL;
-	err = xloop_get_status(xlo, &info64);
-	if (!err)
-		err = xloop_info64_to_old(&info64, &info);
-	if (!err && copy_to_user(arg, &info, sizeof(info)))
-		err = -EFAULT;
-
-	return err;
-}
-
-static int
-xloop_get_status64(struct xloop_device *xlo, struct xloop_info64 __user *arg) {
-	struct xloop_info64 info64;
-	int err;
-
-	if (!arg)
-		return -EINVAL;
-	err = xloop_get_status(xlo, &info64);
-	if (!err && copy_to_user(arg, &info64, sizeof(info64)))
-		err = -EFAULT;
-
-	return err;
-}
-
-static int xloop_set_capacity(struct xloop_device *xlo)
-{
-	loff_t size;
-
-	if (unlikely(xlo->xlo_state != Xlo_bound))
-		return -ENXIO;
-
-	size = get_xloop_size(xlo, xlo->xlo_backing_file);
-	xloop_set_size(xlo, size);
-
-	return 0;
-}
-
-static int xloop_set_dio(struct xloop_device *xlo, unsigned long arg)
-{
-	int error = -ENXIO;
-	if (xlo->xlo_state != Xlo_bound)
-		goto out;
-
-	__xloop_update_dio(xlo, !!arg);
-	if (xlo->use_dio == !!arg)
-		return 0;
-	error = -EINVAL;
- out:
-	return error;
-}
-
-static int xloop_set_block_size(struct xloop_device *xlo, unsigned long arg)
-{
-	int err = 0;
-
-	if (xlo->xlo_state != Xlo_bound)
-		return -ENXIO;
-
-	err = xloop_validate_block_size(arg);
-	if (err)
-		return err;
-
-	if (xlo->xlo_queue->limits.logical_block_size == arg)
-		return 0;
-
-	sync_blockdev(xlo->xlo_device);
-	invalidate_bdev(xlo->xlo_device);
-
-	blk_mq_freeze_queue(xlo->xlo_queue);
-
-	/* invalidate_bdev should have truncated all the pages */
-	if (xlo->xlo_device->bd_inode->i_mapping->nrpages) {
-		err = -EAGAIN;
-		dev_warn(xloop_device_to_dev(xlo), "xloop device has still dirty "
-			"pages (nrpages=%lu)\n",
-			xlo->xlo_device->bd_inode->i_mapping->nrpages);
-		goto out_unfreeze;
-	}
-
-	blk_queue_logical_block_size(xlo->xlo_queue, arg);
-	blk_queue_physical_block_size(xlo->xlo_queue, arg);
-	blk_queue_io_min(xlo->xlo_queue, arg);
-	xloop_update_dio(xlo);
-out_unfreeze:
-	blk_mq_unfreeze_queue(xlo->xlo_queue);
-
-	return err;
-}
-
-static int xlo_simple_ioctl(struct xloop_device *xlo, unsigned int cmd,
-			   unsigned long arg)
-{
-	int err;
-
-	err = mutex_lock_killable(&xloop_ctl_mutex);
-	if (err)
-		return err;
-	switch (cmd) {
-	case XLOOP_SET_CAPACITY:
-		err = xloop_set_capacity(xlo);
-		break;
-	case XLOOP_SET_DIRECT_IO:
-		err = xloop_set_dio(xlo, arg);
-		break;
-	case XLOOP_SET_BLOCK_SIZE:
-		err = xloop_set_block_size(xlo, arg);
-		break;
-	default:
-		err = xlo->ioctl ? xlo->ioctl(xlo, cmd, arg) : -EINVAL;
-	}
-	mutex_unlock(&xloop_ctl_mutex);
-	return err;
-}
-
-static int xlo_ioctl(struct block_device *bdev, fmode_t mode,
-	unsigned int cmd, unsigned long arg)
-{
-	struct xloop_device *xlo = bdev->bd_disk->private_data;
-	void __user *argp = (void __user *) arg;
-	int err;
-
-	switch (cmd) {
-	case XLOOP_SET_FD: {
-		/*
-		 * Legacy case - pass in a zeroed out struct xloop_config with
-		 * only the file descriptor set , which corresponds with the
-		 * default parameters we'd have used otherwise.
-		 */
-		struct xloop_config config;
-
-		memset(&config, 0, sizeof(config));
-		config.fd = arg;
-
-		return xloop_configure(xlo, mode, bdev, &config);
-	}
-	case XLOOP_CONFIGURE: {
-		struct xloop_config config;
-
-		if (copy_from_user(&config, argp, sizeof(config)))
-			return -EFAULT;
-
-		return xloop_configure(xlo, mode, bdev, &config);
-	}
-	case XLOOP_CHANGE_FD:
-		return xloop_change_fd(xlo, bdev, arg);
-	case XLOOP_CLR_FD:
-		return xloop_clr_fd(xlo);
-	case XLOOP_SET_STATUS:
-		err = -EPERM;
-		if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) {
-			err = xloop_set_status_old(xlo, argp);
-		}
-		break;
-	case XLOOP_GET_STATUS:
-		return xloop_get_status_old(xlo, argp);
-	case XLOOP_SET_STATUS64:
-		err = -EPERM;
-		if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) {
-			err = xloop_set_status64(xlo, argp);
-		}
-		break;
-	case XLOOP_GET_STATUS64:
-		return xloop_get_status64(xlo, argp);
-	case XLOOP_SET_CAPACITY:
-	case XLOOP_SET_DIRECT_IO:
-	case XLOOP_SET_BLOCK_SIZE:
-		if (!(mode & FMODE_WRITE) && !capable(CAP_SYS_ADMIN))
-			return -EPERM;
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 4, 0)
-		fallthrough;
-#else
-		/* fall through */
-#endif
-	default:
-		err = xlo_simple_ioctl(xlo, cmd, arg);
-		break;
-	}
-
-	return err;
-}
-
-#ifdef CONFIG_COMPAT
-struct compat_xloop_info {
-	compat_int_t	xlo_number;      /* ioctl r/o */
-	compat_dev_t	xlo_device;      /* ioctl r/o */
-	compat_ulong_t	xlo_inode;       /* ioctl r/o */
-	compat_dev_t	xlo_rdevice;     /* ioctl r/o */
-	compat_int_t	xlo_offset;
-	compat_int_t	xlo_encrypt_type;
-	compat_int_t	xlo_encrypt_key_size;    /* ioctl w/o */
-	compat_int_t	xlo_flags;       /* ioctl r/o */
-	char		xlo_name[XLO_NAME_SIZE];
-	unsigned char	xlo_encrypt_key[XLO_KEY_SIZE]; /* ioctl w/o */
-	compat_ulong_t	xlo_init[2];
-	char		reserved[4];
-	compat_int_t	xlo_file_fmt_type;
-};
-
-/*
- * Transfer 32-bit compatibility structure in userspace to 64-bit xloop info
- * - noinlined to reduce stack space usage in main part of driver
- */
-static noinline int
-xloop_info64_from_compat(const struct compat_xloop_info __user *arg,
-			struct xloop_info64 *info64)
-{
-	struct compat_xloop_info info;
-
-	if (copy_from_user(&info, arg, sizeof(info)))
-		return -EFAULT;
-
-	memset(info64, 0, sizeof(*info64));
-	info64->xlo_number = info.xlo_number;
-	info64->xlo_device = info.xlo_device;
-	info64->xlo_inode = info.xlo_inode;
-	info64->xlo_rdevice = info.xlo_rdevice;
-	info64->xlo_offset = info.xlo_offset;
-	info64->xlo_sizelimit = 0;
-	info64->xlo_encrypt_type = info.xlo_encrypt_type;
-	info64->xlo_encrypt_key_size = info.xlo_encrypt_key_size;
-	info64->xlo_flags = info.xlo_flags;
-	info64->xlo_init[0] = info.xlo_init[0];
-	info64->xlo_init[1] = info.xlo_init[1];
-	info64->xlo_file_fmt_type = info.xlo_file_fmt_type;
-	if (info.xlo_encrypt_type == XLO_CRYPT_CRYPTOAPI)
-		memcpy(info64->xlo_crypt_name, info.xlo_name, XLO_NAME_SIZE);
-	else
-		memcpy(info64->xlo_file_name, info.xlo_name, XLO_NAME_SIZE);
-	memcpy(info64->xlo_encrypt_key, info.xlo_encrypt_key, XLO_KEY_SIZE);
-	return 0;
-}
-
-/*
- * Transfer 64-bit xloop info to 32-bit compatibility structure in userspace
- * - noinlined to reduce stack space usage in main part of driver
- */
-static noinline int
-xloop_info64_to_compat(const struct xloop_info64 *info64,
-		      struct compat_xloop_info __user *arg)
-{
-	struct compat_xloop_info info;
-
-	memset(&info, 0, sizeof(info));
-	info.xlo_number = info64->xlo_number;
-	info.xlo_device = info64->xlo_device;
-	info.xlo_inode = info64->xlo_inode;
-	info.xlo_rdevice = info64->xlo_rdevice;
-	info.xlo_offset = info64->xlo_offset;
-	info.xlo_encrypt_type = info64->xlo_encrypt_type;
-	info.xlo_encrypt_key_size = info64->xlo_encrypt_key_size;
-	info.xlo_flags = info64->xlo_flags;
-	info.xlo_init[0] = info64->xlo_init[0];
-	info.xlo_init[1] = info64->xlo_init[1];
-	info.xlo_file_fmt_type = info64->xlo_file_fmt_type;
-	if (info.xlo_encrypt_type == XLO_CRYPT_CRYPTOAPI)
-		memcpy(info.xlo_name, info64->xlo_crypt_name, XLO_NAME_SIZE);
-	else
-		memcpy(info.xlo_name, info64->xlo_file_name, XLO_NAME_SIZE);
-	memcpy(info.xlo_encrypt_key, info64->xlo_encrypt_key, XLO_KEY_SIZE);
-
-	/* error in case values were truncated */
-	if (info.xlo_device != info64->xlo_device ||
-	    info.xlo_rdevice != info64->xlo_rdevice ||
-	    info.xlo_inode != info64->xlo_inode ||
-	    info.xlo_offset != info64->xlo_offset ||
-	    info.xlo_init[0] != info64->xlo_init[0] ||
-	    info.xlo_init[1] != info64->xlo_init[1] ||
-		info.xlo_file_fmt_type != info64->xlo_file_fmt_type)
-		return -EOVERFLOW;
-
-	if (copy_to_user(arg, &info, sizeof(info)))
-		return -EFAULT;
-	return 0;
-}
-
-static int
-xloop_set_status_compat(struct xloop_device *xlo,
-		       const struct compat_xloop_info __user *arg)
-{
-	struct xloop_info64 info64;
-	int ret;
-
-	ret = xloop_info64_from_compat(arg, &info64);
-	if (ret < 0)
-		return ret;
-	return xloop_set_status(xlo, &info64);
-}
-
-static int
-xloop_get_status_compat(struct xloop_device *xlo,
-		       struct compat_xloop_info __user *arg)
-{
-	struct xloop_info64 info64;
-	int err;
-
-	if (!arg)
-		return -EINVAL;
-	err = xloop_get_status(xlo, &info64);
-	if (!err)
-		err = xloop_info64_to_compat(&info64, arg);
-	return err;
-}
-
-static int xlo_compat_ioctl(struct block_device *bdev, fmode_t mode,
-			   unsigned int cmd, unsigned long arg)
-{
-	struct xloop_device *xlo = bdev->bd_disk->private_data;
-	int err;
-
-	switch(cmd) {
-	case XLOOP_SET_STATUS:
-		err = xloop_set_status_compat(xlo,
-			     (const struct compat_xloop_info __user *)arg);
-		break;
-	case XLOOP_GET_STATUS:
-		err = xloop_get_status_compat(xlo,
-				     (struct compat_xloop_info __user *)arg);
-		break;
-	case XLOOP_SET_CAPACITY:
-	case XLOOP_CLR_FD:
-	case XLOOP_GET_STATUS64:
-	case XLOOP_SET_STATUS64:
-	case XLOOP_CONFIGURE:
-		arg = (unsigned long) compat_ptr(arg);
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 4, 0)
-		fallthrough;
-#else
-		/* fall through */
-#endif
-	case XLOOP_SET_FD:
-	case XLOOP_CHANGE_FD:
-	case XLOOP_SET_BLOCK_SIZE:
-	case XLOOP_SET_DIRECT_IO:
-		err = xlo_ioctl(bdev, mode, cmd, arg);
-		break;
-	default:
-		err = -ENOIOCTLCMD;
-		break;
-	}
-	return err;
-}
-#endif
-
-static int xlo_open(struct block_device *bdev, fmode_t mode)
-{
-	struct xloop_device *xlo;
-	int err;
-
-	err = mutex_lock_killable(&xloop_ctl_mutex);
-	if (err)
-		return err;
-	xlo = bdev->bd_disk->private_data;
-	if (!xlo) {
-		err = -ENXIO;
-		goto out;
-	}
-
-	atomic_inc(&xlo->xlo_refcnt);
-out:
-	mutex_unlock(&xloop_ctl_mutex);
-	return err;
-}
-
-static void xlo_release(struct gendisk *disk, fmode_t mode)
-{
-	struct xloop_device *xlo;
-
-	mutex_lock(&xloop_ctl_mutex);
-	xlo = disk->private_data;
-	if (atomic_dec_return(&xlo->xlo_refcnt))
-		goto out_unlock;
-
-	if (xlo->xlo_flags & XLO_FLAGS_AUTOCLEAR) {
-		if (xlo->xlo_state != Xlo_bound)
-			goto out_unlock;
-		xlo->xlo_state = Xlo_rundown;
-		mutex_unlock(&xloop_ctl_mutex);
-		/*
-		 * In autoclear mode, stop the xloop thread
-		 * and remove configuration after last close.
-		 */
-		__xloop_clr_fd(xlo, true);
-		return;
-	} else if (xlo->xlo_state == Xlo_bound) {
-		/*
-		 * Otherwise keep thread (if running) and config,
-		 * but flush possible ongoing bios in thread.
-		 */
-		blk_mq_freeze_queue(xlo->xlo_queue);
-		blk_mq_unfreeze_queue(xlo->xlo_queue);
-	}
-
-out_unlock:
-	mutex_unlock(&xloop_ctl_mutex);
-}
-
-static const struct block_device_operations xlo_fops = {
-	.owner =	THIS_MODULE,
-	.open =		xlo_open,
-	.release =	xlo_release,
-	.ioctl =	xlo_ioctl,
-#ifdef CONFIG_COMPAT
-	.compat_ioctl =	xlo_compat_ioctl,
-#endif
-};
-
-/*
- * And now the modules code and kernel interface.
- */
-static int max_xloop;
-module_param(max_xloop, int, 0444);
-MODULE_PARM_DESC(max_xloop, "Maximum number of xloop devices");
-module_param(max_part, int, 0444);
-MODULE_PARM_DESC(max_part, "Maximum number of partitions per xloop device");
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Manuel Bentele <development@manuel-bentele.de>");
-MODULE_VERSION(__stringify(VERSION));
-MODULE_ALIAS_BLOCKDEV_MAJOR(XLOOP_MAJOR);
-
-int xloop_register_transfer(struct xloop_func_table *funcs)
-{
-	unsigned int n = funcs->number;
-
-	if (n >= MAX_XLO_CRYPT || xfer_funcs[n])
-		return -EINVAL;
-	xfer_funcs[n] = funcs;
-	return 0;
-}
-
-static int unregister_transfer_cb(int id, void *ptr, void *data)
-{
-	struct xloop_device *xlo = ptr;
-	struct xloop_func_table *xfer = data;
-
-	mutex_lock(&xloop_ctl_mutex);
-	if (xlo->xlo_encryption == xfer)
-		xloop_release_xfer(xlo);
-	mutex_unlock(&xloop_ctl_mutex);
-	return 0;
-}
-
-int xloop_unregister_transfer(int number)
-{
-	unsigned int n = number;
-	struct xloop_func_table *xfer;
-
-	if (n == 0 || n >= MAX_XLO_CRYPT || (xfer = xfer_funcs[n]) == NULL)
-		return -EINVAL;
-
-	xfer_funcs[n] = NULL;
-	idr_for_each(&xloop_index_idr, &unregister_transfer_cb, xfer);
-	return 0;
-}
-
-EXPORT_SYMBOL(xloop_register_transfer);
-EXPORT_SYMBOL(xloop_unregister_transfer);
-
-static blk_status_t xloop_queue_rq(struct blk_mq_hw_ctx *hctx,
-		const struct blk_mq_queue_data *bd)
-{
-	struct request *rq = bd->rq;
-	struct xloop_cmd *cmd = blk_mq_rq_to_pdu(rq);
-	struct xloop_device *xlo = rq->q->queuedata;
-
-	blk_mq_start_request(rq);
-
-	if (xlo->xlo_state != Xlo_bound)
-		return BLK_STS_IOERR;
-
-	switch (req_op(rq)) {
-	case REQ_OP_FLUSH:
-	case REQ_OP_DISCARD:
-	case REQ_OP_WRITE_ZEROES:
-		cmd->use_aio = false;
-		break;
-	default:
-		cmd->use_aio = xlo->use_dio;
-		break;
-	}
-
-	/* always use the first bio's css */
-#ifdef CONFIG_BLK_CGROUP
-	if (cmd->use_aio && rq->bio && rq->bio->bi_blkg) {
-		cmd->css = &bio_blkcg(rq->bio)->css;
-		css_get(cmd->css);
-	} else
-#endif
-		cmd->css = NULL;
-	kthread_queue_work(&xlo->worker, &cmd->work);
-
-	return BLK_STS_OK;
-}
-
-static void xloop_handle_cmd(struct xloop_cmd *cmd)
-{
-	struct request *rq = blk_mq_rq_from_pdu(cmd);
-	const bool write = op_is_write(req_op(rq));
-	struct xloop_device *xlo = rq->q->queuedata;
-	int ret = 0;
-
-	if (write && (xlo->xlo_flags & XLO_FLAGS_READ_ONLY)) {
-		ret = -EIO;
-		goto failed;
-	}
-
-	ret = do_req_filebacked(xlo, rq);
- failed:
-	/* complete non-aio request */
-	if (!cmd->use_aio || ret) {
-		if (ret == -EOPNOTSUPP)
-			cmd->ret = ret;
-		else
-			cmd->ret = ret ? -EIO : 0;
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 9, 0)
-		if (likely(!blk_should_fake_timeout(rq->q)))
-			blk_mq_complete_request(rq);
-#else
-		blk_mq_complete_request(rq);
-#endif
-	}
-}
-
-static void xloop_queue_work(struct kthread_work *work)
-{
-	struct xloop_cmd *cmd =
-		container_of(work, struct xloop_cmd, work);
-
-	xloop_handle_cmd(cmd);
-}
-
-static int xloop_init_request(struct blk_mq_tag_set *set, struct request *rq,
-		unsigned int hctx_idx, unsigned int numa_node)
-{
-	struct xloop_cmd *cmd = blk_mq_rq_to_pdu(rq);
-
-	kthread_init_work(&cmd->work, xloop_queue_work);
-	return 0;
-}
-
-static const struct blk_mq_ops xloop_mq_ops = {
-	.queue_rq     = xloop_queue_rq,
-	.init_request = xloop_init_request,
-	.complete     = xlo_complete_rq,
-};
-
-static struct dentry *xloop_dbgfs_dir;
-
-static int xloop_add(struct xloop_device **l, int i)
-{
-	struct xloop_device *xlo;
-	struct gendisk *disk;
-	int err;
-
-	err = -ENOMEM;
-	xlo = kzalloc(sizeof(*xlo), GFP_KERNEL);
-	if (!xlo)
-		goto out;
-
-	xlo->xlo_state = Xlo_unbound;
-
-	/* allocate id, if @id >= 0, we're requesting that specific id */
-	if (i >= 0) {
-		err = idr_alloc(&xloop_index_idr, xlo, i, i + 1, GFP_KERNEL);
-		if (err == -ENOSPC)
-			err = -EEXIST;
-	} else {
-		err = idr_alloc(&xloop_index_idr, xlo, 0, 0, GFP_KERNEL);
-	}
-	if (err < 0)
-		goto out_free_dev;
-	i = err;
-
-	err = -ENOMEM;
-	xlo->tag_set.ops = &xloop_mq_ops;
-	xlo->tag_set.nr_hw_queues = 1;
-	xlo->tag_set.queue_depth = 128;
-	xlo->tag_set.numa_node = NUMA_NO_NODE;
-	xlo->tag_set.cmd_size = sizeof(struct xloop_cmd);
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
-	xlo->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_STACKING;
-#else
-	xlo->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
-#endif
-	xlo->tag_set.driver_data = xlo;
-
-	err = blk_mq_alloc_tag_set(&xlo->tag_set);
-	if (err)
-		goto out_free_idr;
-
-	xlo->xlo_queue = blk_mq_init_queue(&xlo->tag_set);
-	if (IS_ERR(xlo->xlo_queue)) {
-		err = PTR_ERR(xlo->xlo_queue);
-		goto out_cleanup_tags;
-	}
-	xlo->xlo_queue->queuedata = xlo;
-
-	blk_queue_max_hw_sectors(xlo->xlo_queue, BLK_DEF_MAX_SECTORS);
-
-	/*
-	 * By default, we do buffer IO, so it doesn't make sense to enable
-	 * merge because the I/O submitted to backing file is handled page by
-	 * page. For directio mode, merge does help to dispatch bigger request
-	 * to underlayer disk. We will enable merge once directio is enabled.
-	 */
-	blk_queue_flag_set(QUEUE_FLAG_NOMERGES, xlo->xlo_queue);
-
-	err = -ENOMEM;
-	xlo->xlo_fmt = xloop_file_fmt_alloc();
-	if (!xlo->xlo_fmt)
-		goto out_free_queue;
-
-	xloop_file_fmt_set_xlo(xlo->xlo_fmt, xlo);
-
-	err = -ENOMEM;
-	disk = xlo->xlo_disk = alloc_disk(1 << part_shift);
-	if (!disk)
-		goto out_free_file_fmt;
-
-	/*
-	 * Disable partition scanning by default. The in-kernel partition
-	 * scanning can be requested individually per-device during its
-	 * setup. Userspace can always add and remove partitions from all
-	 * devices. The needed partition minors are allocated from the
-	 * extended minor space, the main xloop device numbers will continue
-	 * to match the xloop minors, regardless of the number of partitions
-	 * used.
-	 *
-	 * If max_part is given, partition scanning is globally enabled for
-	 * all xloop devices. The minors for the main xloop devices will be
-	 * multiples of max_part.
-	 *
-	 * Note: Global-for-all-devices, set-only-at-init, read-only module
-	 * parameteters like 'max_xloop' and 'max_part' make things needlessly
-	 * complicated, are too static, inflexible and may surprise
-	 * userspace tools. Parameters like this in general should be avoided.
-	 */
-	if (!part_shift)
-		disk->flags |= GENHD_FL_NO_PART_SCAN;
-	disk->flags |= GENHD_FL_EXT_DEVT;
-	atomic_set(&xlo->xlo_refcnt, 0);
-	xlo->xlo_number		= i;
-	spin_lock_init(&xlo->xlo_lock);
-	disk->major		= XLOOP_MAJOR;
-	disk->first_minor	= i << part_shift;
-	disk->fops		= &xlo_fops;
-	disk->private_data	= xlo;
-	disk->queue		= xlo->xlo_queue;
-	sprintf(disk->disk_name, "xloop%d", i);
-	add_disk(disk);
-	*l = xlo;
-
-	/* initialize debugfs entries */
-	/* create for each loop device a debugfs directory under 'loop' if
-	 * the 'block' directory exists, otherwise create the loop directory in
-	 * the root directory */
-#ifdef CONFIG_DEBUG_FS
-	xlo->xlo_dbgfs_dir = debugfs_create_dir(disk->disk_name, xloop_dbgfs_dir);
-
-	if (IS_ERR_OR_NULL(xlo->xlo_dbgfs_dir)) {
-		err = -ENODEV;
-		xlo->xlo_dbgfs_dir = NULL;
-		goto out_free_file_fmt;
-	}
-#endif
-
-	return xlo->xlo_number;
-
-out_free_file_fmt:
-	xloop_file_fmt_free(xlo->xlo_fmt);
-out_free_queue:
-	blk_cleanup_queue(xlo->xlo_queue);
-out_cleanup_tags:
-	blk_mq_free_tag_set(&xlo->tag_set);
-out_free_idr:
-	idr_remove(&xloop_index_idr, i);
-out_free_dev:
-	kfree(xlo);
-out:
-	return err;
-}
-
-static void xloop_remove(struct xloop_device *xlo)
-{
-	xloop_file_fmt_free(xlo->xlo_fmt);
-	debugfs_remove(xlo->xlo_dbgfs_dir);
-	del_gendisk(xlo->xlo_disk);
-	blk_cleanup_queue(xlo->xlo_queue);
-	blk_mq_free_tag_set(&xlo->tag_set);
-	put_disk(xlo->xlo_disk);
-	kfree(xlo);
-}
-
-static int find_free_cb(int id, void *ptr, void *data)
-{
-	struct xloop_device *xlo = ptr;
-	struct xloop_device **l = data;
-
-	if (xlo->xlo_state == Xlo_unbound) {
-		*l = xlo;
-		return 1;
-	}
-	return 0;
-}
-
-static int xloop_lookup(struct xloop_device **l, int i)
-{
-	struct xloop_device *xlo;
-	int ret = -ENODEV;
-
-	if (i < 0) {
-		int err;
-
-		err = idr_for_each(&xloop_index_idr, &find_free_cb, &xlo);
-		if (err == 1) {
-			*l = xlo;
-			ret = xlo->xlo_number;
-		}
-		goto out;
-	}
-
-	/* lookup and return a specific i */
-	xlo = idr_find(&xloop_index_idr, i);
-	if (xlo) {
-		*l = xlo;
-		ret = xlo->xlo_number;
-	}
-out:
-	return ret;
-}
-
-static struct kobject *xloop_probe(dev_t dev, int *part, void *data)
-{
-	struct xloop_device *xlo;
-	struct kobject *kobj;
-	int err;
-
-	mutex_lock(&xloop_ctl_mutex);
-	err = xloop_lookup(&xlo, MINOR(dev) >> part_shift);
-	if (err < 0)
-		err = xloop_add(&xlo, MINOR(dev) >> part_shift);
-	if (err < 0)
-		kobj = NULL;
-	else
-		kobj = get_disk_and_module(xlo->xlo_disk);
-	mutex_unlock(&xloop_ctl_mutex);
-
-	*part = 0;
-	return kobj;
-}
-
-static long xloop_control_ioctl(struct file *file, unsigned int cmd,
-			       unsigned long parm)
-{
-	struct xloop_device *xlo;
-	int ret;
-
-	ret = mutex_lock_killable(&xloop_ctl_mutex);
-	if (ret)
-		return ret;
-
-	ret = -ENOSYS;
-	switch (cmd) {
-	case XLOOP_CTL_ADD:
-		ret = xloop_lookup(&xlo, parm);
-		if (ret >= 0) {
-			ret = -EEXIST;
-			break;
-		}
-		ret = xloop_add(&xlo, parm);
-		break;
-	case XLOOP_CTL_REMOVE:
-		ret = xloop_lookup(&xlo, parm);
-		if (ret < 0)
-			break;
-		if (xlo->xlo_state != Xlo_unbound) {
-			ret = -EBUSY;
-			break;
-		}
-		if (atomic_read(&xlo->xlo_refcnt) > 0) {
-			ret = -EBUSY;
-			break;
-		}
-		xlo->xlo_disk->private_data = NULL;
-		idr_remove(&xloop_index_idr, xlo->xlo_number);
-		xloop_remove(xlo);
-		break;
-	case XLOOP_CTL_GET_FREE:
-		ret = xloop_lookup(&xlo, -1);
-		if (ret >= 0)
-			break;
-		ret = xloop_add(&xlo, -1);
-	}
-	mutex_unlock(&xloop_ctl_mutex);
-
-	return ret;
-}
-
-static const struct file_operations xloop_ctl_fops = {
-	.open		= nonseekable_open,
-	.unlocked_ioctl	= xloop_control_ioctl,
-	.compat_ioctl	= xloop_control_ioctl,
-	.owner		= THIS_MODULE,
-	.llseek		= noop_llseek,
-};
-
-static struct miscdevice xloop_misc = {
-	.minor		= XLOOP_CTRL_MINOR,
-	.name		= "xloop-control",
-	.fops		= &xloop_ctl_fops,
-};
-
-MODULE_ALIAS_MISCDEV(XLOOP_CTRL_MINOR);
-MODULE_ALIAS("devname:xloop-control");
-
-static int __init xloop_init(void)
-{
-	int i, nr;
-	unsigned long range;
-	struct xloop_device *xlo;
-	int err;
-
-	part_shift = 0;
-	if (max_part > 0) {
-		part_shift = fls(max_part);
-
-		/*
-		 * Adjust max_part according to part_shift as it is exported
-		 * to user space so that user can decide correct minor number
-		 * if [s]he want to create more devices.
-		 *
-		 * Note that -1 is required because partition 0 is reserved
-		 * for the whole disk.
-		 */
-		max_part = (1UL << part_shift) - 1;
-	}
-
-	if ((1UL << part_shift) > DISK_MAX_PARTS) {
-		err = -EINVAL;
-		goto err_out;
-	}
-
-	if (max_xloop > 1UL << (MINORBITS - part_shift)) {
-		err = -EINVAL;
-		goto err_out;
-	}
-
-	/*
-	 * If max_xloop is specified, create that many devices upfront.
-	 * This also becomes a hard limit. If max_xloop is not specified,
-	 * create CONFIG_BLK_DEV_XLOOP_MIN_COUNT xloop devices at module
-	 * init time. xloop devices can be requested on-demand with the
-	 * /dev/xloop-control interface, or be instantiated by accessing
-	 * a 'dead' device node.
-	 */
-	if (max_xloop) {
-		nr = CONFIG_BLK_DEV_XLOOP_MIN_COUNT;
-		range = 1UL << MINORBITS;
-	}
-
-	err = misc_register(&xloop_misc);
-	if (err < 0)
-		goto err_out;
-
-
-	if (register_blkdev(XLOOP_MAJOR, "xloop")) {
-		err = -EIO;
-		goto misc_out;
-	}
-
-#ifdef CONFIG_DEBUG_FS
-	xloop_dbgfs_dir = debugfs_create_dir("xloop", NULL);
-	if (IS_ERR_OR_NULL(xloop_dbgfs_dir)) {
-		err = -ENODEV;
-		goto misc_out;
-	}
-#endif
-
-	blk_register_region(MKDEV(XLOOP_MAJOR, 0), range,
-				  THIS_MODULE, xloop_probe, NULL, NULL);
-
-	/* pre-create number of devices given by config or max_xloop */
-	mutex_lock(&xloop_ctl_mutex);
-	for (i = 0; i < nr; i++)
-		xloop_add(&xlo, i);
-	mutex_unlock(&xloop_ctl_mutex);
-
-	pr_info("module in version %s loaded\n", __stringify(VERSION));
-	return 0;
-
-misc_out:
-	misc_deregister(&xloop_misc);
-err_out:
-	return err;
-}
-
-static int xloop_exit_cb(int id, void *ptr, void *data)
-{
-	struct xloop_device *xlo = ptr;
-
-	xloop_remove(xlo);
-	return 0;
-}
-
-static void __exit xloop_exit(void)
-{
-	unsigned long range;
-
-	range = max_xloop ? max_xloop << part_shift : 1UL << MINORBITS;
-
-	mutex_lock(&xloop_ctl_mutex);
-
-	idr_for_each(&xloop_index_idr, &xloop_exit_cb, NULL);
-	idr_destroy(&xloop_index_idr);
-
-	blk_unregister_region(MKDEV(XLOOP_MAJOR, 0), range);
-	unregister_blkdev(XLOOP_MAJOR, "xloop");
-
-#ifdef CONFIG_DEBUG_FS
-	debugfs_remove(xloop_dbgfs_dir);
-#endif
-
-	misc_deregister(&xloop_misc);
-
-	mutex_unlock(&xloop_ctl_mutex);
-
-	pr_info("exit module\n");
-}
-
-module_init(xloop_init);
-module_exit(xloop_exit);
-
-#ifndef MODULE
-static int __init max_xloop_setup(char *str)
-{
-	max_xloop = simple_strtol(str, NULL, 0);
-	return 1;
-}
-
-__setup("max_xloop=", max_xloop_setup);
-#endif