linux-dev/drivers/block/null_blk, branch linus/master

block: null_blk: Fix null_zone_write()

2022-06-02T13:11:28Z

The bio and rq fields of struct nullb_cmd are now overlapping in a union. So we cannot use a test on ->bio being non-NULL to detect the NULL_Q_BIO queue mode. null_zone_write() use such broken test to set the sector position of a zone append write in the command bio or request. When the null_blk device uses the NULL_Q_MQ queue mode, null_zone_write() wrongly end up setting the bio sector position, resulting in the command request to be broken and random crashes following. Fix this by testing the device queue mode directly. Fixes: 8ba816b23abd ("null-blk: save memory footprint for struct nullb_cmd") Signed-off-by: Damien Le Moal Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20220602120344.1365329-1-damien.lemoal@opensource.wdc.com Signed-off-by: Jens Axboe

block: null_blk: Improve device creation with configfs

2022-05-04T11:24:58Z

Currently, the directory name used to create a nullb device through sysfs is not used as the device name, potentially causing headaches for users if devices are already created through the modprobe operation withe the nr_device module parameter not set to 0. E.g. a user can do "mkdir /sys/kernel/config/nullb/nullb0" to create a nullb device even though /dev/nullb0 was already created by modprobe. In this case, the configfs nullb device will be named nullb1, causing confusion for the user. Simplify this by using the configfs directory name as the nullb device name, always, unless another nullb device is already using the same name. E.g. if modprobe created nullb0, then: $ mkdir /sys/kernel/config/nullb/nullb0 mkdir: cannot create directory '/sys/kernel/config/nullb/nullb0': File exists will be reported to the user. To implement this, the function null_find_dev_by_name() is added to check for the existence of a nullb device with the name used for a new configfs device directory. nullb_group_make_item() uses this new function to check if the directory name can be used as the disk name. Finally, null_add_dev() is modified to use the device config item name as the disk name for a new nullb device created using configfs. The naming of devices created though modprobe remains unchanged. Of note is that it is possible for a user to create through configfs a nullb device with the same name as an existing device. E.g. $ mkdir /sys/kernel/config/nullb/null will successfully create the nullb device named "null" but this block device will however not appear under /dev/ since /dev/null already exists. Suggested-by: Joseph Bacik Signed-off-by: Damien Le Moal Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20220420005718.3780004-5-damien.lemoal@opensource.wdc.com Signed-off-by: Jens Axboe

block: null_blk: Cleanup messages

2022-05-04T11:24:58Z

Use the pr_fmt() macro to prefix all null_blk pr_xxx() messages with "null_blk:" to clarify which module is printing the messages. Also add a pr_info() message in null_add_dev() to print the name of a newly created disk. Signed-off-by: Damien Le Moal Reviewed-by: Chaitanya Kulkarni Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20220420005718.3780004-4-damien.lemoal@opensource.wdc.com Signed-off-by: Jens Axboe

block: null_blk: Cleanup device creation and deletion

2022-05-04T11:24:58Z

Introduce the null_create_dev() and null_destroy_dev() helper functions to respectivel create nullb devices on modprobe and destroy them on rmmod. The null_destroy_dev() helper avoids duplicated code in the null_init() and null_exit() functions for deleting devices. Signed-off-by: Damien Le Moal Reviewed-by: Chaitanya Kulkarni Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20220420005718.3780004-3-damien.lemoal@opensource.wdc.com Signed-off-by: Jens Axboe

block: null_blk: Fix code style issues

2022-05-04T11:24:58Z

Fix message grammar and code style issues (brackets and indentation) in null_init(). Signed-off-by: Damien Le Moal Reviewed-by: Chaitanya Kulkarni Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20220420005718.3780004-2-damien.lemoal@opensource.wdc.com Signed-off-by: Jens Axboe

null_blk: don't set the discard_alignment queue limit

2022-05-03T16:38:50Z

The discard_alignment queue limit is named a bit misleading means the offset into the block device at which the discard granularity starts. Setting it to the discard granularity as done by null_blk is mostly harmless but also useless. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Reviewed-by: Chaitanya Kulkarni Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20220418045314.360785-4-hch@lst.de Signed-off-by: Jens Axboe

null-blk: save memory footprint for struct nullb_cmd

2022-04-26T02:31:20Z

Total 16 bytes can be saved in two ways: 1) The field 'bio' will only be used in bio based mode, and the field 'rq' will only be used in mq mode. Since they won't be used in the same time, declare a union for them. 2) The field 'bool fake_timeout' can be placed in the hole after the field 'error'. Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20220426022133.3999006-1-yukuai3@huawei.com Signed-off-by: Jens Axboe

block: remove QUEUE_FLAG_DISCARD

2022-04-18T01:49:59Z

Just use a non-zero max_discard_sectors as an indicator for discard support, similar to what is done for write zeroes. The only places where needs special attention is the RAID5 driver, which must clear discard support for security reasons by default, even if the default stacking rules would allow for it. Signed-off-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Acked-by: Christoph Böhmwalder [drbd] Acked-by: Jan Höppner [s390] Acked-by: Coly Li [bcache] Acked-by: David Sterba [btrfs] Reviewed-by: Chaitanya Kulkarni Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de Signed-off-by: Jens Axboe

block: null_blk: end timed out poll request

2022-04-14T16:16:33Z

When poll request is timed out, it is removed from the poll list, but not completed, so the request is leaked, and never get chance to complete. Fix the issue by ending it in timeout handler. Fixes: 0a593fbbc245 ("null_blk: poll queue support") Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20220413084836.1571995-1-ming.lei@redhat.com Signed-off-by: Jens Axboe

null_blk: null_alloc_page() cleanup

2022-02-27T21:49:49Z

Remove goto labels and use direct returns as error unwinding code only needs to free t_page variable if we alloc_pages() call fails as having two labels for one kfree() can be avoided easily. Signed-off-by: Chaitanya Kulkarni Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20220222152852.26043-3-kch@nvidia.com Signed-off-by: Jens Axboe