Checkpatch.pl warns there are 2 locations of smp_mb() and smp_wmb()
without code comment. This patch adds the missing code comments for
these memory barrier calls.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This is warned by checkpatch.pl, this patch removes the extra space.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The SPDX header is missing fro closure.c, super.c and util.c, this
patch adds SPDX header for GPL-2.0 into these files.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This is not a preferred style to place open brace '{' at the end of
function definition, checkpatch.pl reports error for such coding
style. This patch moves them into the start of the next new line.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch declares char * array with const prefix in sysfs.c,
which is suggested by checkpatch.pl.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch fixes 3 style issues warned by checkpatch.pl,
- Comment lines are not aligned
- Comments use "/*" on subsequent lines
- Comment lines use a trailing "*/"
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

kmem_cache_destroy() is safe for NULL pointer as input, the NULL pointer
checking is unncessary. This patch just removes the NULL pointer checking
to make code simpler.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Current bcache Kconfig uses '---help---' as header of help information,
for now 'help' is prefered. This patch fixes this style by replacing
'---help---' by 'help' in bcache Kconfig file.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch fixes typo 'succesfully' to correct 'successfully', which is
suggested by checkpatch.pl.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

'%pF' and '%pf' are deprecated vsprintf pointer extensions, this patch
replace them by '%pS', which is suggested by checkpatch.pl.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

bch_btree_insert_check_key() has unaligned indent, or indent by blank
characters. This patch makes the indent aligned and replace blank by
tabs.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

There are still many places in bcache use printk to display kernel
message, which are suggested to be preplaced by pr_*() routines like
pr_err(), pr_info(), or pr_notice().

This patch replaces all printk() with a proper pr_*() routine for
bcache code.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Symbolic permission names are used in bcache, for now octal permission
numbers are encouraged to use for readability. This patch replaces
all symbolic permissions by octal permission numbers.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch fixes the lines over 80 characters into more lines, to minimize
warnings by checkpatch.pl. There are still some lines exceed 80 characters,
but it is better to be a single line and I don't change them.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

There are many function definitions do not have identifier argument names,
scripts/checkpatch.pl complains warnings like this,

 WARNING: function definition argument 'struct bcache_device *' should
  also have an identifier name
  #16735: FILE: writeback.h:120:
  +void bch_sectors_dirty_init(struct bcache_device *);

This patch adds identifier argument names to all bcache function
definitions to fix such warnings.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed: Shenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch fixes warning reported by checkpatch.pl by replacing 'unsigned'
with 'unsigned int'.
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Commit ea8c5356 ("bcache: set max writeback rate when I/O request
is idle") changes struct bch_ratelimit member rate from uint32_t to
atomic_long_t and uses atomic_long_set() in drivers/md/bcache/sysfs.c
to set new writeback rate, after the input is converted from memory
buf to long int by sysfs_strtoul_clamp().

The above change has a problem because there is an implicit return
inside sysfs_strtoul_clamp() so the following atomic_long_set()
won't be called. This error is detected by 0day system with following
snipped smatch warnings:

drivers/md/bcache/sysfs.c:271 __cached_dev_store() error: uninitialized
symbol 'v'.
270  sysfs_strtoul_clamp(writeback_rate, v, 1, INT_MAX);
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@271 atomic_long_set(&dc->writeback_rate.rate, v);

This patch fixes the above error by using strtoul_safe_clamp() to
convert the input buffer into a long int type result.

Fixes: ea8c5356 ("bcache: set max writeback rate when I/O request is idle")
Cc: Kai Krakow <kai@kaishome.de>
Cc: Stefan Priebe <s.priebe@profihost.ag>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

sparse complains:

drivers/block/null_blk_main.c:816:24: sparse: context imbalance in 'null_insert_page' - unexpected unlock

Fix it by adding the necessary annotations to the function.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 1056543 ("Missing break in switch")
Addresses-Coverity-ID: 1056544 ("Missing break in switch")
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Remove the tailing backslash in macro BTREE_FLAG in btree.h
Signed-off-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The pr_err statement in the code for sysfs_attatch section would run
for various error codes, which maybe confusing.

E.g,

Run the command twice:
   echo 796b5c05-b03c-4bc7-9cbd-a8df5e8be891 > \
				/sys/block/bcache0/bcache/attach
   [the backing dev got attached on the first run]
   echo 796b5c05-b03c-4bc7-9cbd-a8df5e8be891 > \
				/sys/block/bcache0/bcache/attach

In dmesg, after the command run twice, we can get:
	bcache: bch_cached_dev_attach() Can't attach sda6: already attached
	bcache: __cached_dev_store() Can't attach 796b5c05-b03c-4bc7-9cbd-\
a8df5e8be891
               : cache set not found
The first statement in the message was right, but the second was
confusing.

bch_cached_dev_attach has various pr_ statements for various error
codes, except ENOENT.

After the change, rerun above command twice:
	echo 796b5c05-b03c-4bc7-9cbd-a8df5e8be891 > \
			/sys/block/bcache0/bcache/attach
	echo 796b5c05-b03c-4bc7-9cbd-a8df5e8be891 > \
			/sys/block/bcache0/bcache/attach

In dmesg we only got:
	bcache: bch_cached_dev_attach() Can't attach sda6: already attached
No confusing "cache set not found" message anymore.

And for some not exist SET-UUID:
	echo 796b5c05-b03c-4bc7-9cbd-a8df5e8be898 > \
			/sys/block/bcache0/bcache/attach
In dmesg we can get:
	bcache: __cached_dev_store() Can't attach 796b5c05-b03c-4bc7-9cbd-\
a8df5e8be898
	               : cache set not found
Signed-off-by: NShenghui Wang <shhuiw@foxmail.com>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Commit b1092c9a ("bcache: allow quick writeback when backing idle")
allows the writeback rate to be faster if there is no I/O request on a
bcache device. It works well if there is only one bcache device attached
to the cache set. If there are many bcache devices attached to a cache
set, it may introduce performance regression because multiple faster
writeback threads of the idle bcache devices will compete the btree level
locks with the bcache device who have I/O requests coming.

This patch fixes the above issue by only permitting fast writebac when
all bcache devices attached on the cache set are idle. And if one of the
bcache devices has new I/O request coming, minimized all writeback
throughput immediately and let PI controller __update_writeback_rate()
to decide the upcoming writeback rate for each bcache device.

Also when all bcache devices are idle, limited wrieback rate to a small
number is wast of thoughput, especially when backing devices are slower
non-rotation devices (e.g. SATA SSD). This patch sets a max writeback
rate for each backing device if the whole cache set is idle. A faster
writeback rate in idle time means new I/Os may have more available space
for dirty data, and people may observe a better write performance then.

Please note bcache may change its cache mode in run time, and this patch
still works if the cache mode is switched from writeback mode and there
is still dirty data on cache.

Fixes: Commit b1092c9a ("bcache: allow quick writeback when backing idle")
Cc: stable@vger.kernel.org #4.16+
Signed-off-by: NColy Li <colyli@suse.de>
Tested-by: NKai Krakow <kai@kaishome.de>
Tested-by: NStefan Priebe <s.priebe@profihost.ag>
Cc: Michael Lyle <mlyle@lyle.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch tries to add code comments in bset.c, to make some
tricky code and designment to be more comprehensible. Most information
of this patch comes from the discussion between Kent and I, he
offers very informative details. If there is any mistake
of the idea behind the code, no doubt that's from me misrepresentation.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch updates code comment in bch_keylist_realloc() by fixing
incorrected function names, to make the code to be more comprehennsible.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch updates the code comment in struct cache with correct array
names, to make the code to be more comprehensible.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch adds a line of code comment in super.c:register_bdev(), to
make code to be more comprehensible.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

In bch_btree_node_get() the read-in btree node will be partially
prefetched into L1 cache for following bset iteration (if there is).
But if the btree node read is failed, the perfetch operations will
waste L1 cache space. This patch checkes whether read operation and
only does cache prefetch when read I/O succeeded.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

When writeback is not running, writeback rate should be 0, other value is
misleading. And the following dyanmic writeback rate debug parameters
should be 0 too,
	rate, proportional, integral, change
otherwise they are misleading when writeback is not running.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Greg KH suggests that normal code should not care about debugfs. Therefore
no matter successful or failed of debugfs_create_dir() execution, it is
unncessary to check its return value.

There are two functions called debugfs_create_dir() and check the return
value, which are bch_debug_init() and closure_debug_init(). This patch
changes these two functions from int to void type, and ignore return values
of debugfs_create_dir().

This patch does not fix exact bug, just makes things work as they should.
Signed-off-by: NColy Li <colyli@suse.de>
Suggested-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Cc: Kai Krakow <kai@kaishome.de>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

kmem_cache_destroy has taken null pointer into account. So it is
safe to drop the null check before calling the function.
Signed-off-by: Nzhong jiang <zhongjiang@huawei.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

mempool_destroy has taken the null pointer into account. So it is safe
to remove the null check.
Signed-off-by: Nzhong jiang <zhongjiang@huawei.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

debugfs_remove_recursive has taken null pointer into account. So it is
safe to drop the null check before calling the function.
Signed-off-by: Nzhong jiang <zhongjiang@huawei.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

When the user supplies a ctrl_loss_tmo < 0, we warn them that this will
cause the fabrics layer to attempt reconnection forever.  However, in
reality the fabrics layer never attempts to reconnect because the
condition to test whether we should reconnect is backwards in this case.
Signed-off-by: NTal Shorer <tal.shorer@gmail.com>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch implements the Namespace Write Protect feature described in
"NVMe TP 4005a Namespace Write Protect". In this version, we implement
No Write Protect and Write Protect states for target ns which can be
toggled by set-features commands from the host side.

For write-protect state transition, we need to flush the ns specified
as a part of command so we also add helpers for carrying out synchronous
flush operations.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[hch: fixed an incorrect endianess conversion, minor cleanups]
Signed-off-by: NChristoph Hellwig <hch@lst.de>

NVMe 1.3 TP 4005 introduces new filed (NSATTR). This field indicates
whether given namespace is write protected or not. This patch sets the
gendisk associated with the namespace to read only based on the identify
namespace nsattr field.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The target loopback driver is a low-level driver for the SCSI subsystem,
and as such needs to depend on it.

Fixes: 8a39a047 ("target: don't depend on SCSI")
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

When the initial discovery fails the subsystem hasn't been setup yet
in nvme_mpath_stop, and we can't dereference ctrl->subsys.

Fixes: 0d0b660f ("nvme: add ANA support")
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Return statements in functions returning bool should use true or false
instead of an integer value.

This code was detected with the help of Coccinelle.
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

A minor version number increase should not break backwards
compatibility.

Fixes: 3cb98f84 ("lightnvm: add minor version to generic geometry")
Reviewed-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <mb@lightnvm.io>
Signed-off-by: NJens Axboe <axboe@kernel.dk>