linux.git/drivers/block/null_blk/main.c, branch v6.0

null_blk: fix ida error handling in null_add_dev()

2022-08-02T23:22:41+00:00

There needs to be some error checking if ida_simple_get() fails.
Also call ida_free() if there are errors later.

Fixes: 94bc02e30fb8 ("nullb: use ida to manage index")
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/YtEhXsr6vJeoiYhd@kili
Signed-off-by: Jens Axboe

null_blk: add configfs variables for 2 options

2022-08-02T23:15:02+00:00

Allow setting via configfs these two options:

no_sched
shared_tag_bitmap

Previously these could only be activated as module parameters.

Still missing are:

shared_tags
timeout
requeue
init_hctx

Signed-off-by: Vincent Fu 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20220708174943.87787-3-vincent.fu@samsung.com
[axboe: fold in nullb == NULL fix]
Signed-off-by: Jens Axboe

null_blk: add module parameters for 4 options

2022-08-02T23:14:50+00:00

Add as module parameters these options:

memory_backed
discard
mbps
cache_size

Previously these could only be set via configfs.

Still missing is bad_blocks.

The kernel test robot found a documentation formatting issue in v1 of
this patch.

Reported-by: kernel test robot 
Signed-off-by: Vincent Fu 
Link: https://lore.kernel.org/r/20220708174943.87787-2-vincent.fu@samsung.com
Signed-off-by: Jens Axboe

block: null_blk: Use the bitmap API to allocate bitmaps

2022-08-02T23:14:44+00:00

Use bitmap_zalloc()/bitmap_free() instead of hand-writing them.

It is less verbose and it improves the semantic.

Signed-off-by: Christophe JAILLET 
Link: https://lore.kernel.org/r/7c4d3116ba843fc4a8ae557dd6176352a6cd0985.1656864320.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jens Axboe

treewide: Rename enum req_opf into enum req_op

2022-07-14T18:14:30+00:00

The type name enum req_opf is misleading since it suggests that values of
this type include both an operation type and flags. Since values of this
type represent an operation only, change the type name into enum req_op.

Convert the enum req_op documentation into kernel-doc format. Move a few
definitions such that the enum req_op documentation occurs just above
the enum req_op definition.

The name "req_opf" was introduced by commit ef295ecf090d ("block: better op
and flags encoding").

Cc: Christoph Hellwig 
Cc: Ming Lei 
Cc: Hannes Reinecke 
Cc: Damien Le Moal 
Cc: Johannes Thumshirn 
Signed-off-by: Bart Van Assche 
Link: https://lore.kernel.org/r/20220714180729.1065367-2-bvanassche@acm.org
Signed-off-by: Jens Axboe

blk-mq: Drop blk_mq_ops.timeout 'reserved' arg

2022-07-06T12:33:53+00:00

With new API blk_mq_is_reserved_rq() we can tell if a request is from
the reserved pool, so stop passing 'reserved' arg. There is actually
only a single user of that arg for all the callback implementations, which
can use blk_mq_is_reserved_rq() instead.

This will also allow us to stop passing the same 'reserved' around the
blk-mq iter functions next.

Signed-off-by: John Garry 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Bart Van Assche 
Reviewed-by: Hannes Reinecke 
Acked-by: Ulf Hansson  # For MMC
Reviewed-by: Martin K. Petersen 
Link: https://lore.kernel.org/r/1657109034-206040-4-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe

block: remove blk_cleanup_disk

2022-06-28T12:33:15+00:00

blk_cleanup_disk is nothing but a trivial wrapper for put_disk now,
so remove it.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Hannes Reinecke 
Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de
Signed-off-by: Jens Axboe

block: null_blk: Fix null_zone_write()

2022-06-02T13:11:28+00:00

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

2022-05-04T11:24:58+00:00

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

2022-05-04T11:24:58+00:00

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