From 0c3796c244598122a5d59d56f30d19390096817f Mon Sep 17 00:00:00 2001 From: Martijn Coenen Date: Wed, 13 May 2020 15:38:41 +0200 Subject: loop: Factor out configuring loop from status Factor out this code into a separate function, so it can be reused by other code more easily. Signed-off-by: Martijn Coenen Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/block/loop.c | 117 +++++++++++++++++++++++++++++---------------------- 1 file changed, 67 insertions(+), 50 deletions(-) (limited to 'drivers/block') diff --git a/drivers/block/loop.c b/drivers/block/loop.c index e281a9f03d96..6a4c0ba225ca 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1251,75 +1251,43 @@ static int loop_clr_fd(struct loop_device *lo) return __loop_clr_fd(lo, false); } +/** + * loop_set_status_from_info - configure device from loop_info + * @lo: struct loop_device to configure + * @info: struct loop_info64 to configure the device with + * + * Configures the loop device parameters according to the passed + * in loop_info64 configuration. + */ static int -loop_set_status(struct loop_device *lo, const struct loop_info64 *info) +loop_set_status_from_info(struct loop_device *lo, + const struct loop_info64 *info) { int err; struct loop_func_table *xfer; kuid_t uid = current_uid(); - struct block_device *bdev; - bool partscan = false; - bool size_changed = false; - - err = mutex_lock_killable(&loop_ctl_mutex); - if (err) - return err; - if (lo->lo_encrypt_key_size && - !uid_eq(lo->lo_key_owner, uid) && - !capable(CAP_SYS_ADMIN)) { - err = -EPERM; - goto out_unlock; - } - if (lo->lo_state != Lo_bound) { - err = -ENXIO; - goto out_unlock; - } - if ((unsigned int) info->lo_encrypt_key_size > LO_KEY_SIZE) { - err = -EINVAL; - goto out_unlock; - } - - if (lo->lo_offset != info->lo_offset || - lo->lo_sizelimit != info->lo_sizelimit) { - size_changed = true; - sync_blockdev(lo->lo_device); - kill_bdev(lo->lo_device); - } - /* I/O need to be drained during transfer transition */ - blk_mq_freeze_queue(lo->lo_queue); - - if (size_changed && lo->lo_device->bd_inode->i_mapping->nrpages) { - /* If any pages were dirtied after kill_bdev(), try again */ - err = -EAGAIN; - pr_warn("%s: loop%d (%s) has still dirty pages (nrpages=%lu)\n", - __func__, lo->lo_number, lo->lo_file_name, - lo->lo_device->bd_inode->i_mapping->nrpages); - goto out_unfreeze; - } + if ((unsigned int) info->lo_encrypt_key_size > LO_KEY_SIZE) + return -EINVAL; err = loop_release_xfer(lo); if (err) - goto out_unfreeze; + return err; if (info->lo_encrypt_type) { unsigned int type = info->lo_encrypt_type; - if (type >= MAX_LO_CRYPT) { - err = -EINVAL; - goto out_unfreeze; - } + if (type >= MAX_LO_CRYPT) + return -EINVAL; xfer = xfer_funcs[type]; - if (xfer == NULL) { - err = -EINVAL; - goto out_unfreeze; - } + if (xfer == NULL) + return -EINVAL; } else xfer = NULL; err = loop_init_xfer(lo, xfer, info); if (err) - goto out_unfreeze; + return err; lo->lo_offset = info->lo_offset; lo->lo_sizelimit = info->lo_sizelimit; @@ -1346,6 +1314,55 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) lo->lo_key_owner = uid; } + return 0; +} + +static int +loop_set_status(struct loop_device *lo, const struct loop_info64 *info) +{ + int err; + struct block_device *bdev; + kuid_t uid = current_uid(); + bool partscan = false; + bool size_changed = false; + + err = mutex_lock_killable(&loop_ctl_mutex); + if (err) + return err; + if (lo->lo_encrypt_key_size && + !uid_eq(lo->lo_key_owner, uid) && + !capable(CAP_SYS_ADMIN)) { + err = -EPERM; + goto out_unlock; + } + if (lo->lo_state != Lo_bound) { + err = -ENXIO; + goto out_unlock; + } + + if (lo->lo_offset != info->lo_offset || + lo->lo_sizelimit != info->lo_sizelimit) { + size_changed = true; + sync_blockdev(lo->lo_device); + kill_bdev(lo->lo_device); + } + + /* I/O need to be drained during transfer transition */ + blk_mq_freeze_queue(lo->lo_queue); + + if (size_changed && lo->lo_device->bd_inode->i_mapping->nrpages) { + /* If any pages were dirtied after kill_bdev(), try again */ + err = -EAGAIN; + pr_warn("%s: loop%d (%s) has still dirty pages (nrpages=%lu)\n", + __func__, lo->lo_number, lo->lo_file_name, + lo->lo_device->bd_inode->i_mapping->nrpages); + goto out_unfreeze; + } + + err = loop_set_status_from_info(lo, info); + if (err) + goto out_unfreeze; + if (size_changed) { loff_t new_size = get_size(lo->lo_offset, lo->lo_sizelimit, lo->lo_backing_file); -- cgit v1.2.3