[ Upstream commit 6c4ca1e36c ]
register_shrinker is now __must_check, so check it to kill a warning.
Caller of bch_btree_cache_alloc in super.c appropriately checks return
value so this is fully plumbed through.
This V2 fixes checkpatch warnings and improves the commit description,
as I was too hasty getting the previous version out.
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Vojtech Pavlik <vojtech@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit c157313791 ]
Currently, Cache missed IOs are identified by s->cache_miss, but actually,
there are many situations that missed IOs are not assigned a value for
s->cache_miss in cached_dev_cache_miss(), for example, a bypassed IO
(s->iop.bypass = 1), or the cache_bio allocate failed. In these situations,
it will go to out_put or out_submit, and s->cache_miss is null, which leads
bch_mark_cache_accounting() to treat this IO as a hit IO.
[ML: applied by 3-way merge]
Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 330a4db89d ]
mutex_destroy does nothing most of time, but it's better to call
it to make the code future proof and it also has some meaning
for like mutex debug.
As Coly pointed out in a previous review, bcache_exit() may not be
able to handle all the references properly if userspace registers
cache and backing devices right before bch_debug_init runs and
bch_debug_init failes later. So not exposing userspace interface
until everything is ready to avoid that issue.
Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Coly Li <colyli@suse.de>
Reviewed-by: Eric Wheeler <bcache@linux.ewheeler.net>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e393aa2446 upstream.
When we send a read request and hit the clean data in cache device, there
is a situation called cache read race in bcache(see the commit in the tail
of cache_look_up(), the following explaination just copy from there):
The bucket we're reading from might be reused while our bio is in flight,
and we could then end up reading the wrong data. We guard against this
by checking (in bch_cache_read_endio()) if the pointer is stale again;
if so, we treat it as an error (s->iop.error = -EINTR) and reread from
the backing device (but we don't pass that error up anywhere)
It should be noted that cache read race happened under normal
circumstances, not the circumstance when SSD failed, it was counted
and shown in /sys/fs/bcache/XXX/internal/cache_read_races.
Without this patch, when we use writeback mode, we will never reread from
the backing device when cache read race happened, until the whole cache
device is clean, because the condition
(s->recoverable && (dc && !atomic_read(&dc->has_dirty))) is false in
cached_dev_read_error(). In this situation, the s->iop.error(= -EINTR)
will be passed up, at last, user will receive -EINTR when it's bio end,
this is not suitable, and wield to up-application.
In this patch, we use s->read_dirty_data to judge whether the read
request hit dirty data in cache device, it is safe to reread data from
the backing device when the read request hit clean data. This can not
only handle cache read race, but also recover data when failed read
request from cache device.
[edited by mlyle to fix up whitespace, commit log title, comment
spelling]
Fixes: d59b237959 ("bcache: only permit to recovery read error when cache device is clean")
Signed-off-by: Hua Rui <huarui.dev@gmail.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d59b237959 upstream.
When bcache does read I/Os, for example in writeback or writethrough mode,
if a read request on cache device is failed, bcache will try to recovery
the request by reading from cached device. If the data on cached device is
not synced with cache device, then requester will get a stale data.
For critical storage system like database, providing stale data from
recovery may result an application level data corruption, which is
unacceptible.
With this patch, for a failed read request in writeback or writethrough
mode, recovery a recoverable read request only happens when cache device
is clean. That is to say, all data on cached device is up to update.
For other cache modes in bcache, read request will never hit
cached_dev_read_error(), they don't need this patch.
Please note, because cache mode can be switched arbitrarily in run time, a
writethrough mode might be switched from a writeback mode. Therefore
checking dc->has_data in writethrough mode still makes sense.
Changelog:
V4: Fix parens error pointed by Michael Lyle.
v3: By response from Kent Oversteet, he thinks recovering stale data is a
bug to fix, and option to permit it is unnecessary. So this version
the sysfs file is removed.
v2: rename sysfs entry from allow_stale_data_on_failure to
allow_stale_data_on_failure, and fix the confusing commit log.
v1: initial patch posted.
[small change to patch comment spelling by mlyle]
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Reported-by: Arne Wolf <awolf@lenovo.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Nix <nix@esperi.org.uk>
Cc: Kai Krakow <hurikhan77@gmail.com>
Cc: Eric Wheeler <bcache@lists.ewheeler.net>
Cc: Junhui Tang <tang.junhui@zte.com.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cf33c1ee52 upstream.
This patch try to fix the building error on MIPS. The reason is MIPS
has already defined the PTR macro, which conflicts with the PTR macro
in include/uapi/linux/bcache.h.
[fixed by mlyle: corrected a line-length issue]
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 91af8300d9 upstream.
In bcache code, sysfs entries are created before all resources get
allocated, e.g. allocation thread of a cache set.
There is posibility for NULL pointer deference if a resource is accessed
but which is not initialized yet. Indeed Jorg Bornschein catches one on
cache set allocation thread and gets a kernel oops.
The reason for this bug is, when bch_bucket_alloc() is called during
cache set registration and attaching, ca->alloc_thread is not properly
allocated and initialized yet, call wake_up_process() on ca->alloc_thread
triggers NULL pointer deference failure. A simple and fast fix is, before
waking up ca->alloc_thread, checking whether it is allocated, and only
wake up ca->alloc_thread when it is not NULL.
Signed-off-by: Coly Li <colyli@suse.de>
Reported-by: Jorg Bornschein <jb@capsec.org>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9276717b9e upstream.
Most importantly, solve a crash where %llu was used to format signed
numbers. This would cause a buffer overflow when reading sysfs
writeback_rate_debug, as only 20 bytes were allocated for this and
%llu writes 20 characters plus a null.
Always use the units mechanism rather than having different output
paths for simplicity.
Also, correct problems with display output where 1.10 was a larger
number than 1.09, by multiplying by 10 and then dividing by 1024 instead
of dividing by 100. (Remainders of >= 1000 would print as .10).
Minor changes: Always display the decimal point instead of trying to
omit it based on number of digits shown. Decide what units to use
based on 1000 as a threshold, not 1024 (in other words, always print
at most 3 digits before the decimal point).
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Reported-by: Dmitry Yu Okunev <dyokunev@ut.mephi.ru>
Acked-by: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 77fa100f27 upstream.
If you encounter any errors in bch_cached_dev_attach it will return
a negative error code. The variable 'v' which stores the result is
unsigned, thus user space sees a very large value returned for bytes
written which can cause incorrect user space behavior. Utilize 1
signed variable to use throughout the function to preserve error return
capability.
Signed-off-by: Tony Asleson <tasleson@redhat.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a8394090a9 upstream.
__update_write_rate() uses a Proportion-Differentiation Controller
algorithm to control writeback rate. A dirty target number is used in
this PD controller to control writeback rate. A larger target number
will make the writeback rate smaller, on the versus, a smaller target
number will make the writeback rate larger.
bcache uses the following steps to calculate the target number,
1) cache_sectors = all-buckets-of-cache-set * buckets-size
2) cache_dirty_target = cache_sectors * cached-device-writeback_percent
3) target = cache_dirty_target *
(sectors-of-cached-device/sectors-of-all-cached-devices-of-this-cache-set)
The calculation at step 1) for cache_sectors is incorrect, which does
not consider dirty blocks occupied by flash only volume.
A flash only volume can be took as a bcache device without cached
device. All data sectors allocated for it are persistent on cache device
and marked dirty, they are not touched by bcache writeback and garbage
collection code. So data blocks of flash only volume should be ignore
when calculating cache_sectors of cache set.
Current code does not subtract dirty sectors of flash only volume, which
results a larger target number from the above 3 steps. And in sequence
the cache device's writeback rate is smaller then a correct value,
writeback speed is slower on all cached devices.
This patch fixes the incorrect slower writeback rate by subtracting
dirty sectors of flash only volumes in __update_writeback_rate().
(Commit log composed by Coly Li to pass checkpatch.pl checking)
Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4b758df21e upstream.
If blkdev_get_by_path() in register_bcache() fails, we try to lookup the
block device using lookup_bdev() to detect which situation we are in to
properly report error. However we never drop the reference returned to
us from lookup_bdev(). Fix that.
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 175206cf9a upstream.
bcache uses a Proportion-Differentiation Controller algorithm to control
writeback rate to cached devices. In the PD controller algorithm, dirty
stripes of thin flash device should not be counted in, because flash only
volumes never write back dirty data.
Currently dirty stripe counter for thin flash device is not initialized
when the thin flash device starts. Which means the following calculation
in PD controller will reference an undefined dirty stripes number, and
all cached devices attached to the same cache set where the thin flash
device lies on may have an inaccurate writeback rate.
This patch calles bch_sectors_dirty_init() in flash_dev_run(), to
correctly initialize dirty stripe counter when the thin flash device
starts to run. This patch also does following parameter data type change,
-void bch_sectors_dirty_init(struct cached_dev *dc);
+void bch_sectors_dirty_init(struct bcache_device *);
to call this function conveniently in flash_dev_run().
(Commit log is composed by Coly Li)
Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit acc9cf8c66 upstream.
This patch fixes a cachedev registration-time allocation deadlock.
This can deadlock on boot if your initrd auto-registeres bcache devices:
Allocator thread:
[ 720.727614] INFO: task bcache_allocato:3833 blocked for more than 120 seconds.
[ 720.732361] [<ffffffff816eeac7>] schedule+0x37/0x90
[ 720.732963] [<ffffffffa05192b8>] bch_bucket_alloc+0x188/0x360 [bcache]
[ 720.733538] [<ffffffff810e6950>] ? prepare_to_wait_event+0xf0/0xf0
[ 720.734137] [<ffffffffa05302bd>] bch_prio_write+0x19d/0x340 [bcache]
[ 720.734715] [<ffffffffa05190bf>] bch_allocator_thread+0x3ff/0x470 [bcache]
[ 720.735311] [<ffffffff816ee41c>] ? __schedule+0x2dc/0x950
[ 720.735884] [<ffffffffa0518cc0>] ? invalidate_buckets+0x980/0x980 [bcache]
Registration thread:
[ 720.710403] INFO: task bash:3531 blocked for more than 120 seconds.
[ 720.715226] [<ffffffff816eeac7>] schedule+0x37/0x90
[ 720.715805] [<ffffffffa05235cd>] __bch_btree_map_nodes+0x12d/0x150 [bcache]
[ 720.716409] [<ffffffffa0522d30>] ? bch_btree_insert_check_key+0x1c0/0x1c0 [bcache]
[ 720.717008] [<ffffffffa05236e4>] bch_btree_insert+0xf4/0x170 [bcache]
[ 720.717586] [<ffffffff810e6950>] ? prepare_to_wait_event+0xf0/0xf0
[ 720.718191] [<ffffffffa0527d9a>] bch_journal_replay+0x14a/0x290 [bcache]
[ 720.718766] [<ffffffff810cc90d>] ? ttwu_do_activate.constprop.94+0x5d/0x70
[ 720.719369] [<ffffffff810cf684>] ? try_to_wake_up+0x1d4/0x350
[ 720.719968] [<ffffffffa05317d0>] run_cache_set+0x580/0x8e0 [bcache]
[ 720.720553] [<ffffffffa053302e>] register_bcache+0xe2e/0x13b0 [bcache]
[ 720.721153] [<ffffffff81354cef>] kobj_attr_store+0xf/0x20
[ 720.721730] [<ffffffff812a2dad>] sysfs_kf_write+0x3d/0x50
[ 720.722327] [<ffffffff812a225a>] kernfs_fop_write+0x12a/0x180
[ 720.722904] [<ffffffff81225177>] __vfs_write+0x37/0x110
[ 720.723503] [<ffffffff81228048>] ? __sb_start_write+0x58/0x110
[ 720.724100] [<ffffffff812cedb3>] ? security_file_permission+0x23/0xa0
[ 720.724675] [<ffffffff812258a9>] vfs_write+0xa9/0x1b0
[ 720.725275] [<ffffffff8102479c>] ? do_audit_syscall_entry+0x6c/0x70
[ 720.725849] [<ffffffff81226755>] SyS_write+0x55/0xd0
[ 720.726451] [<ffffffff8106a390>] ? do_page_fault+0x30/0x80
[ 720.727045] [<ffffffff816f2cae>] system_call_fastpath+0x12/0x71
The fifo code in upstream bcache can't use the last element in the buffer,
which was the cause of the bug: if you asked for a power of two size,
it'd give you a fifo that could hold one less than what you asked for
rather than allocating a buffer twice as big.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f8b11260a4 upstream.
When bch_cache_set_alloc() fails to kzalloc the cache_set, the
asyncronous closure handling tries to dereference a cache_set that
hadn't yet been allocated inside of cache_set_flush() which is called
by __cache_set_unregister() during cleanup. This appears to happen only
during an OOM condition on bcache_register.
Signed-off-by: Eric Wheeler <bcache@linux.ewheeler.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 07cc6ef8ed upstream.
The bch_writeback_thread might BUG_ON in read_dirty() if
dc->sb==BDEV_STATE_DIRTY and bch_sectors_dirty_init has not yet completed
its related initialization. This patch downs the dc->writeback_lock until
after initialization is complete, thus preventing bch_writeback_thread
from proceeding prematurely.
See this thread:
http://thread.gmane.org/gmane.linux.kernel.bcache.devel/3453
Signed-off-by: Eric Wheeler <bcache@linux.ewheeler.net>
Tested-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 627ccd20b4 upstream.
Previously, it would only scan the entire disk if it was starting from
the very start of the disk - i.e. if the previous scan got to the end.
This was broken by refill_full_stripes(), which updates last_scanned so
that refill_dirty was never triggering the searched_from_start path.
But if we change refill_dirty() to always scan the entire disk if
necessary, regardless of what last_scanned was, the code gets cleaner
and we fix that bug too.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8d16ce540c upstream.
Added a safeguard in the shutdown case. At least while not being
attached it is also possible to trigger a kernel bug by writing into
writeback_running. This change adds the same check before trying to
wake up the thread for that case.
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2ef9ccbfcb upstream.
Subject : [PATCH v2] bcache: fix a livelock in btree lock
Date : Wed, 25 Feb 2015 20:32:09 +0800 (02/25/2015 04:32:09 AM)
This commit tries to fix a livelock in bcache. This livelock might
happen when we causes a huge number of cache misses simultaneously.
When we get a cache miss, bcache will execute the following path.
->cached_dev_make_request()
->cached_dev_read()
->cached_lookup()
->bch->btree_map_keys()
->btree_root() <------------------------
->bch_btree_map_keys_recurse() |
->cache_lookup_fn() |
->cached_dev_cache_miss() |
->bch_btree_insert_check_key() -|
[If btree->seq is not equal to seq + 1, we should return
EINTR and traverse btree again.]
In bch_btree_insert_check_key() function we first need to check upgrade
flag (op->lock == -1), and when this flag is true we need to release
read btree->lock and try to take write btree->lock. During taking and
releasing this write lock, btree->seq will be monotone increased in
order to prevent other threads modify this in cache miss (see btree.h:74).
But if there are some cache misses caused by some requested, we could
meet a livelock because btree->seq is always changed by others. Thus no
one can make progress.
This commit will try to take write btree->lock if it encounters a race
when we traverse btree. Although it sacrifice the scalability but we
can ensure that only one can modify the btree.
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Tested-by: Joshua Schmid <jschmid@suse.com>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Joshua Schmid <jschmid@suse.com>
Cc: Zhu Yanhai <zhu.yanhai@gmail.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull block IO poll support from Jens Axboe:
"Various groups have been doing experimentation around IO polling for
(really) fast devices. The code has been reviewed and has been
sitting on the side for a few releases, but this is now good enough
for coordinated benchmarking and further experimentation.
Currently O_DIRECT sync read/write are supported. A framework is in
the works that allows scalable stats tracking so we can auto-tune
this. And we'll add libaio support as well soon. Fow now, it's an
opt-in feature for test purposes"
* 'for-4.4/io-poll' of git://git.kernel.dk/linux-block:
direct-io: be sure to assign dio->bio_bdev for both paths
directio: add block polling support
NVMe: add blk polling support
block: add block polling support
blk-mq: return tag/queue combo in the make_request_fn handlers
block: change ->make_request_fn() and users to return a queue cookie
Pull trivial updates from Jiri Kosina:
"Trivial stuff from trivial tree that can be trivially summed up as:
- treewide drop of spurious unlikely() before IS_ERR() from Viresh
Kumar
- cosmetic fixes (that don't really affect basic functionality of the
driver) for pktcdvd and bcache, from Julia Lawall and Petr Mladek
- various comment / printk fixes and updates all over the place"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
bcache: Really show state of work pending bit
hwmon: applesmc: fix comment typos
Kconfig: remove comment about scsi_wait_scan module
class_find_device: fix reference to argument "match"
debugfs: document that debugfs_remove*() accepts NULL and error values
net: Drop unlikely before IS_ERR(_OR_NULL)
mm: Drop unlikely before IS_ERR(_OR_NULL)
fs: Drop unlikely before IS_ERR(_OR_NULL)
drivers: net: Drop unlikely before IS_ERR(_OR_NULL)
drivers: misc: Drop unlikely before IS_ERR(_OR_NULL)
UBI: Update comments to reflect UBI_METAONLY flag
pktcdvd: drop null test before destroy functions
No functional changes in this patch, but it prepares us for returning
a more useful cookie related to the IO that was queued up.
Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
WORK_STRUCT_PENDING is a mask for testing the pending bit.
test_bit() expects the number of the bit and we need to
use WORK_STRUCT_PENDING_BIT there.
Also work_data_bits() is defined in workqueues.h now.
I have noticed this just by chance when looking how
WORK_STRUCT_PENDING_BIT is used. The change is compile
tested.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The bcache driver has always accepted arbitrarily large bios and split
them internally. Now that every driver must accept arbitrarily large
bios this code isn't nessecary anymore.
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dpark@posteo.net>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently we have two different ways to signal an I/O error on a BIO:
(1) by clearing the BIO_UPTODATE flag
(2) by returning a Linux errno value to the bi_end_io callback
The first one has the drawback of only communicating a single possible
error (-EIO), and the second one has the drawback of not beeing persistent
when bios are queued up, and are not passed along from child to parent
bio in the ever more popular chaining scenario. Having both mechanisms
available has the additional drawback of utterly confusing driver authors
and introducing bugs where various I/O submitters only deal with one of
them, and the others have to add boilerplate code to deal with both kinds
of error returns.
So add a new bi_error field to store an errno value directly in struct
bio and remove the existing mechanisms to clean all this up.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Some drivers use it now, others just set the limits field manually.
But in preparation for splitting this into a hard and soft limit,
ensure that they all call the proper function for setting the hw
limit for discards.
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This is horribly confusing, it breaks the flow of the code without
it being apparent in the caller.
Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.
This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it. c files
which need access to more backing-dev details now include
backing-dev.h directly. This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.
v2: fs/fat build failure fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
Commit c4cf5261 ("bio: skip atomic inc/dec of ->bi_remaining for
non-chains") regressed all existing callers that followed this pattern:
1) saving a bio's original bi_end_io
2) wiring up an intermediate bi_end_io
3) restoring the original bi_end_io from intermediate bi_end_io
4) calling bio_endio() to execute the restored original bi_end_io
The regression was due to BIO_CHAIN only ever getting set if
bio_inc_remaining() is called. For the above pattern it isn't set until
step 3 above (step 2 would've needed to establish BIO_CHAIN). As such
the first bio_endio(), in step 2 above, never decremented __bi_remaining
before calling the intermediate bi_end_io -- leaving __bi_remaining with
the value 1 instead of 0. When bio_inc_remaining() occurred during step
3 it brought it to a value of 2. When the second bio_endio() was
called, in step 4 above, it should've called the original bi_end_io but
it didn't because there was an extra reference that wasn't dropped (due
to atomic operations being optimized away since BIO_CHAIN wasn't set
upfront).
Fix this issue by removing the __bi_remaining management complexity for
all callers that use the above pattern -- bio_chain() is the only
interface that _needs_ to be concerned with __bi_remaining. For the
above pattern callers just expect the bi_end_io they set to get called!
Remove bio_endio_nodec() and also remove all bio_inc_remaining() calls
that aren't associated with the bio_chain() interface.
Also, the bio_inc_remaining() interface has been moved local to bio.c.
Fixes: c4cf5261 ("bio: skip atomic inc/dec of ->bi_remaining for non-chains")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Struct bio has a reference count that controls when it can be freed.
Most uses cases is allocating the bio, which then returns with a
single reference to it, doing IO, and then dropping that single
reference. We can remove this atomic_dec_and_test() in the completion
path, if nobody else is holding a reference to the bio.
If someone does call bio_get() on the bio, then we flag the bio as
now having valid count and that we must properly honor the reference
count when it's being put.
Tested-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Use generic io stats accounting help functions (generic_{start,end}_io_acct)
to simplify io stat accounting.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Acked-by: Kent Overstreet <kmo@datera.io>
Signed-off-by: Jens Axboe <axboe@fb.com>
Clear QUEUE_FLAG_ADD_RANDOM in all block drivers that set
QUEUE_FLAG_NONROT.
Historically, all block devices have automatically made entropy
contributions. But as previously stated in commit e2e1a148 ("block: add
sysfs knob for turning off disk entropy contributions"):
- On SSD disks, the completion times aren't as random as they
are for rotational drives. So it's questionable whether they
should contribute to the random pool in the first place.
- Calling add_disk_randomness() has a lot of overhead.
There are more reliable sources for randomness than non-rotational block
devices. From a security perspective it is better to err on the side of
caution than to allow entropy contributions from unreliable "random"
sources.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
this is needed for the queue/block device we created (it's done by
blk_cleanup_queue() which we do call) - but calling it for the block devices we
only opened is pointless.
Change-Id: I53dfded14ed15b9581d10ca8399d5e1b3abbf9f2
Since bch_is_open will iterate linked list bch_cache_sets and
uncached_devices, it needs bch_register_lock.
Signed-off-by: Jianjian Huo <samuel.huo@gmail.com>
time_stats::btree_gc_max_duration_mc is not bit shifted by 8
Fixes BUG #138
Change-Id: I44fc6e1d0579674016acc533f1a546b080e5371a
Signed-off-by: Surbhi Palande <sap@daterainc.com>
If register_cache_set() failed, we would touch ca->set after
it had already been freed. Also, fix an assertion to catch
this.
Change-Id: I748e5f5b223e2d9b2602075dec2f997cced2394d
If we goto out_nocoalesce after we free new_nodes[0], we end up freeing
new_nodes[0] again. This was generating a lockdep warning. The fix is
to set new_nodes[0] to NULL, since the out_nocoalesce path safely
ignores NULL entries in the new_nodes array.
This regression was introduced in 2d7f9531.
Change-Id: I76564d7257800583214376b4bacf236cda90c89c
