Commit Graph

233 Commits

Author SHA1 Message Date
Kent Overstreet
72a44517f3 bcache: Convert gc to a kthread
We needed a dedicated rescuer workqueue for gc anyways... and gc was
conceptually a dedicated thread, just one that wasn't running all the
time. Switch it to a dedicated thread to make the code a bit more
straightforward.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:04 -08:00
Kent Overstreet
35fcd848d7 bcache: Convert bucket_wait to wait_queue_head_t
At one point we did do fancy asynchronous waiting stuff with
bucket_wait, but that's all gone (and bucket_wait is used a lot less
than it used to be). So use the standard primitives.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:04 -08:00
Kent Overstreet
e8e1d4682c bcache: Convert try_wait to wait_queue_head_t
We never waited on c->try_wait asynchronously, so just use the standard
primitives.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:03 -08:00
Kent Overstreet
0b93207abb bcache: Move keylist out of btree_op
Slowly working on pruning struct btree_op - the aim is for it to only
contain things that are actually necessary for traversing the btree.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:02 -08:00
Kent Overstreet
a34a8bfd4e bcache: Refactor journalling flow control
Making things less asynchronous that don't need to be - bch_journal()
only has to block when the journal or journal entry is full, which is
emphatically not a fast path. So make it a normal function that just
returns when it finishes, to make the code and control flow easier to
follow.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:02 -08:00
Kent Overstreet
cdd972b164 bcache: Refactor read request code a bit
More refactoring, and renaming.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:01 -08:00
Kent Overstreet
84f0db03ea bcache: Refactor request_write()
Try to improve some of the naming a bit to be more consistent, and also
improve the flow of control in request_write() a bit.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:00 -08:00
Kent Overstreet
c2f95ae2eb bcache: Clean up keylist code
More random refactoring.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:00 -08:00
Kent Overstreet
4f3d40147b bcache: Add explicit keylist arg to btree_insert()
Some refactoring - better to explicitly pass stuff around instead of
having it all in the "big bag of state", struct btree_op. Going to prune
struct btree_op quite a bit over time.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:59 -08:00
Kent Overstreet
e7c590eb63 bcache: Convert btree_insert_check_key() to btree_insert_node()
This was the main point of all this refactoring - now,
btree_insert_check_key() won't fail just because the leaf node happened
to be full.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:59 -08:00
Kent Overstreet
403b6cdeb1 bcache: Insert multiple keys at a time
We'll often end up with a list of adjacent keys to insert -
because bch_data_insert() may have to fragment the data it writes.

Originally, to simplify things and avoid having to deal with corner
cases bch_btree_insert() would pass keys from this list one at a time to
btree_insert_recurse() - mainly because the list of keys might span leaf
nodes, so it was easier this way.

With the btree_insert_node() refactoring, it's now a lot easier to just
pass down the whole list and have btree_insert_recurse() iterate over
leaf nodes until it's done.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:58 -08:00
Kent Overstreet
26c949f806 bcache: Add btree_insert_node()
The flow of control in the old btree insertion code was rather -
backwards; we'd recurse down the btree (in btree_insert_recurse()), and
then if we needed to split the keys to be inserted into the parent node
would be effectively returned up to btree_insert_recurse(), which would
notice there was more work to do and finish the insertion.

The main problem with this was that the full logic for btree insertion
could only be used by calling btree_insert_recurse; if you'd gotten to a
btree leaf some other way and had a key to insert, if it turned out that
node needed to be split you were SOL.

This inverts the flow of control so btree_insert_node() does _full_
btree insertion, including splitting - and takes a (leaf) btree node to
insert into as a parameter.

This means we can now _correctly_ handle cache misses - for cache
misses, we need to insert a fake "check" key into the btree when we
discover we have a cache miss - while we still have the btree locked.
Previously, if the btree node was full inserting a cache miss would just
fail.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:57 -08:00
Kent Overstreet
d6fd3b11ce bcache: Explicitly track btree node's parent
This is prep work for the reworked btree insertion code.

The way we set b->parent is ugly and hacky... the problem is, when
btree_split() or garbage collection splits or rewrites a btree node, the
parent changes for all its (potentially already cached) children.

I may change this later and add some code to look through the btree node
cache and find all our cached child nodes and change the parent pointer
then...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:57 -08:00
Kent Overstreet
8304ad4dc8 bcache: Remove unnecessary check in should_split()
Checking i->seq was redundant, because since ages ago we always
initialize the new bset when advancing b->written

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:56 -08:00
Kent Overstreet
2d679fc756 bcache: Stripe size isn't necessarily a power of two
Originally I got this right... except that the divides didn't use
do_div(), which broke 32 bit kernels. When I went to fix that, I forgot
that the raid stripe size usually isn't a power of two... doh

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:55 -08:00
Kent Overstreet
77c320eb46 bcache: Add on error panic/unregister setting
Works kind of like the ext4 setting, to panic or remount read only on
errors.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:55 -08:00
Kent Overstreet
49b1212dfa bcache: Use blkdev_issue_discard()
The old asynchronous discard code was really a relic from when all the
allocation code was asynchronous - now that allocation runs out of a
dedicated thread there's no point in keeping around all that complicated
machinery.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:54 -08:00
Kent Overstreet
dd9ec84da5 bcache: Fix a lockdep splat
bch_keybuf_del() takes a spinlock that can't be taken in interrupt context -
whoops. Fortunately, this code isn't enabled by default (you have to toggle a
sysfs thing).

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:54 -08:00
Kent Overstreet
7857d5d470 bcache: Fix a journalling performance bug 2013-11-10 21:55:53 -08:00
Kent Overstreet
1fa8455deb bcache: Fix dirty_data accounting
Dirty data accounting wasn't quite right - firstly, we were adding the key we're
inserting after it could have merged with another dirty key already in the
btree, and secondly we could sometimes pass the wrong offset to
bcache_dev_sectors_dirty_add() for dirty data we were overwriting - which is
important when tracking dirty data by stripe.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-11-10 21:55:27 -08:00
Kent Overstreet
d4eddd42f5 bcache: Fixed incorrect order of arguments to bio_alloc_bioset()
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-23 07:55:36 +01:00
Kent Overstreet
2fe80d3bbf bcache: Fix a null ptr deref regression
Commit c0f04d88e4 ("bcache: Fix flushes in writeback mode") was fixing
a reported data corruption bug, but it seems some last minute
refactoring or rebasing introduced a null pointer deref.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Reported-by: Gabriel de Perthuis <g2p.code@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-10 18:17:39 -07:00
Kent Overstreet
c0f04d88e4 bcache: Fix flushes in writeback mode
In writeback mode, when we get a cache flush we need to make sure we
issue a flush to the backing device.

The code for sending down an extra flush was wrong - by cloning the bio
we were probably getting flags that didn't make sense for a bare flush,
and also the old code was firing for FUA bios, for which we don't need
to send a flush to the backing device.

This was causing data corruption somehow - the mechanism was never
determined, but this patch fixes it for the users that were seeing it.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet
84786438ed bcache: Fix for handling overlapping extents when reading in a btree node
btree_sort_fixup() was overly clever, because it was trying to avoid
pulling a key off the btree iterator in more than one place.

This led to a really obscure bug where we'd break early from the loop in
btree_sort_fixup() if the current key overlapped with keys in more than
one older set, and the next key it overlapped with was zero size.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet
a698e08c82 bcache: Fix a shrinker deadlock
GFP_NOIO means we could be getting called recursively - mca_alloc() ->
mca_data_alloc() - definitely can't use mutex_lock(bucket_lock) then.
Whoops.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet
79e3dab90d bcache: Fix a dumb CPU spinning bug in writeback
schedule_timeout() != schedule_timeout_uninterruptible()

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet
1394d6761b bcache: Fix a flush/fua performance bug
bch_journal_meta() was missing the flush to make the journal write
actually go down (instead of waiting up to journal_delay_ms)...

Whoops

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet
c2a4f3183a bcache: Fix a writeback performance regression
Background writeback works by scanning the btree for dirty data and
adding those keys into a fixed size buffer, then for each dirty key in
the keybuf writing it to the backing device.

When read_dirty() finishes and it's time to scan for more dirty data, we
need to wait for the outstanding writeback IO to finish - they still
take up slots in the keybuf (so that foreground writes can check for
them to avoid races) - without that wait, we'll continually rescan when
we'll be able to add at most a key or two to the keybuf, and that takes
locks that starves foreground IO.  Doh.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Geert Uytterhoeven
61cbd250f8 bcache: Correct printf()-style format length modifier
Fix

  drivers/md/bcache/btree.c: In function ‘bch_btree_node_read’:
  drivers/md/bcache/btree.c:259: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 3 has type ‘size_t’

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet
c426c4fd46 bcache: Fix for when no journal entries are found
The journal replay code didn't handle this case, causing it to go into
an infinite loop...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Gabriel de Perthuis
aee6f1cfff bcache: Strip endline when writing the label through sysfs
sysfs attributes with unusual characters have crappy failure modes
in Squeeze (udev 164); later versions of udev are unaffected.

This should make these characters more unusual.

Signed-off-by: Gabriel de Perthuis <g2p.code@gmail.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet
6d9d21e35f bcache: Fix a dumb journal discard bug
That switch statement was obviously wrong, leading to some sort of weird
spinning on rare occasion with discards enabled...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Dave Chinner
7dc19d5aff drivers: convert shrinkers to new count/scan API
Convert the driver shrinkers to the new API.  Most changes are compile
tested only because I either don't have the hardware or it's staging
stuff.

FWIW, the md and android code is pretty good, but the rest of it makes me
want to claw my eyes out.  The amount of broken code I just encountered is
mind boggling.  I've added comments explaining what is broken, but I fear
that some of the code would be best dealt with by being dragged behind the
bike shed, burying in mud up to it's neck and then run over repeatedly
with a blunt lawn mower.

Special mention goes to the zcache/zcache2 drivers.  They can't co-exist
in the build at the same time, they are under different menu options in
menuconfig, they only show up when you've got the right set of mm
subsystem options configured and so even compile testing is an exercise in
pulling teeth.  And that doesn't even take into account the horrible,
broken code...

[glommer@openvz.org: fixes for i915, android lowmem, zcache, bcache]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@openvz.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10 18:56:32 -04:00
Linus Torvalds
d4c90b1b9f Merge branch 'for-3.11/drivers' of git://git.kernel.dk/linux-block
Pull block IO driver bits from Jens Axboe:
 "As I mentioned in the core block pull request, due to real life
  circumstances the driver pull request would be late.  Now it looks
  like -rc2 late...  On the plus side, apart form the rsxx update, these
  are all things that I could argue could go in later in the cycle as
  they are fixes and not features.  So even though things are late, it's
  not ALL bad.

  The pull request contains:

   - Updates to bcache, all bug fixes, from Kent.

   - A pile of drbd bug fixes (no big features this time!).

   - xen blk front/back fixes.

   - rsxx driver updates, some of them deferred form 3.10.  So should be
     well cooked by now"

* 'for-3.11/drivers' of git://git.kernel.dk/linux-block: (63 commits)
  bcache: Allocation kthread fixes
  bcache: Fix GC_SECTORS_USED() calculation
  bcache: Journal replay fix
  bcache: Shutdown fix
  bcache: Fix a sysfs splat on shutdown
  bcache: Advertise that flushes are supported
  bcache: check for allocation failures
  bcache: Fix a dumb race
  bcache: Use standard utility code
  bcache: Update email address
  bcache: Delete fuzz tester
  bcache: Document shrinker reserve better
  bcache: FUA fixes
  drbd: Allow online change of al-stripes and al-stripe-size
  drbd: Constants should be UPPERCASE
  drbd: Ignore the exit code of a fence-peer handler if it returns too late
  drbd: Fix rcu_read_lock balance on error path
  drbd: fix error return code in drbd_init()
  drbd: Do not sleep inside rcu
  bcache: Refresh usage docs
  ...
2013-07-22 19:02:52 -07:00
Kent Overstreet
79826c35eb bcache: Allocation kthread fixes
The alloc kthread should've been using try_to_freeze() - and also there
was the potential for the alloc kthread to get woken up after it had
shut down, which would have been bad.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-07-12 00:22:49 -07:00
Kent Overstreet
29ebf465b9 bcache: Fix GC_SECTORS_USED() calculation
Part of the job of garbage collection is to add up however many sectors
of live data it finds in each bucket, but that doesn't work very well if
it doesn't reset GC_SECTORS_USED() when it starts. Whoops.

This wouldn't have broken anything horribly, but allocation tries to
preferentially reclaim buckets that are mostly empty and that's not
gonna work with an incorrect GC_SECTORS_USED() value.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-07-12 00:22:48 -07:00
Kent Overstreet
faa5673617 bcache: Journal replay fix
The journal replay code starts by finding something that looks like a
valid journal entry, then it does a binary search over the unchecked
region of the journal for the journal entries with the highest sequence
numbers.

Trouble is, the logic was wrong - journal_read_bucket() returns true if
it found journal entries we need, but if the range of journal entries
we're looking for loops around the end of the journal - in that case
journal_read_bucket() could return true when it hadn't found the highest
sequence number we'd seen yet, and in that case the binary search did
the wrong thing. Whoops.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-07-12 00:22:48 -07:00
Kent Overstreet
5caa52afc5 bcache: Shutdown fix
Stopping a cache set is supposed to make it stop attached backing
devices, but somewhere along the way that code got lost. Fixing this
mainly has the effect of fixing our reboot notifier.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-07-12 00:22:47 -07:00
Kent Overstreet
c9502ea442 bcache: Fix a sysfs splat on shutdown
If we stopped a bcache device when we were already detaching (or
something like that), bcache_device_unlink() would try to remove a
symlink from sysfs that was already gone because the bcache dev kobject
had already been removed from sysfs.

So keep track of whether we've removed stuff from sysfs.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-07-12 00:22:47 -07:00
Kent Overstreet
54d12f2b4f bcache: Advertise that flushes are supported
Whoops - bcache's flush/FUA was mostly correct, but flushes get filtered
out unless we say we support them...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-07-12 00:22:46 -07:00
Dan Carpenter
d2a65ce2ac bcache: check for allocation failures
There is a missing NULL check after the kzalloc().

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
2013-07-12 00:22:46 -07:00
Kent Overstreet
6aa8f1a6ca bcache: Fix a dumb race
In the far-too-complicated closure code - closures can have destructors,
for probably dubious reasons; they get run after the closure is no
longer waiting on anything but before dropping the parent ref, intended
just for freeing whatever memory the closure is embedded in.

Trouble is, when remaining goes to 0 and we've got nothing more to run -
we also have to unlock the closure, setting remaining to -1. If there's
a destructor, that unlock isn't doing anything - nobody could be trying
to lock it if we're about to free it - but if the unlock _is needed...
that check for a destructor was racy. Argh.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-07-12 00:22:33 -07:00
Linus Torvalds
80cc38b163 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "The usual stuff from trivial tree"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
  treewide: relase -> release
  Documentation/cgroups/memory.txt: fix stat file documentation
  sysctl/net.txt: delete reference to obsolete 2.4.x kernel
  spinlock_api_smp.h: fix preprocessor comments
  treewide: Fix typo in printk
  doc: device tree: clarify stuff in usage-model.txt.
  open firmware: "/aliasas" -> "/aliases"
  md: bcache: Fixed a typo with the word 'arithmetic'
  irq/generic-chip: fix a few kernel-doc entries
  frv: Convert use of typedef ctl_table to struct ctl_table
  sgi: xpc: Convert use of typedef ctl_table to struct ctl_table
  doc: clk: Fix incorrect wording
  Documentation/arm/IXP4xx fix a typo
  Documentation/networking/ieee802154 fix a typo
  Documentation/DocBook/media/v4l fix a typo
  Documentation/video4linux/si476x.txt fix a typo
  Documentation/virtual/kvm/api.txt fix a typo
  Documentation/early-userspace/README fix a typo
  Documentation/video4linux/soc-camera.txt fix a typo
  lguest: fix CONFIG_PAE -> CONFIG_x86_PAE in comment
  ...
2013-07-04 11:40:58 -07:00
Kent Overstreet
8e51e414a3 bcache: Use standard utility code
Some of bcache's utility code has made it into the rest of the kernel,
so drop the bcache versions.

Bcache used to have a workaround for allocating from a bio set under
generic_make_request() (if you allocated more than once, the bios you
already allocated would get stuck on current->bio_list when you
submitted, and you'd risk deadlock) - bcache would mask out __GFP_WAIT
when allocating bios under generic_make_request() so that allocation
could fail and it could retry from workqueue. But bio_alloc_bioset() has
a workaround now, so we can drop this hack and the associated error
handling.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-07-01 14:43:53 -07:00
Kent Overstreet
f3059a5461 bcache: Delete fuzz tester
This code has rotted and it hasn't been used in ages anyways.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-07-01 14:43:48 -07:00
Kent Overstreet
36c9ea9837 bcache: Document shrinker reserve better
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-07-01 14:42:48 -07:00
Kent Overstreet
e49c7c374e bcache: FUA fixes
Journal writes need to be marked FUA, not just REQ_FLUSH. And btree node
writes have... weird ordering requirements.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-07-01 14:42:47 -07:00
Gabriel de Perthuis
ab9e14002e bcache: Send label uevents
Signed-off-by: Gabriel de Perthuis <g2p.code@gmail.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 21:58:06 -07:00
Gabriel de Perthuis
a25c32bede bcache: Send a uevent with a cached device's UUID
Signed-off-by: Gabriel de Perthuis <g2p.code@gmail.com>
2013-06-26 21:58:05 -07:00
Kent Overstreet
72c270612b bcache: Write out full stripes
Now that we're tracking dirty data per stripe, we can add two
optimizations for raid5/6:

 * If a stripe is already dirty, force writes to that stripe to
   writeback mode - to help build up full stripes of dirty data

 * When flushing dirty data, preferentially write out full stripes first
   if there are any.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 21:58:04 -07:00
Kent Overstreet
279afbad4e bcache: Track dirty data by stripe
To make background writeback aware of raid5/6 stripes, we first need to
track the amount of dirty data within each stripe - we do this by
breaking up the existing sectors_dirty into per stripe atomic_ts

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 21:57:23 -07:00
Kent Overstreet
444fc0b6b1 bcache: Initialize sectors_dirty when attaching
Previously, dirty_data wouldn't get initialized until the first garbage
collection... which was a bit of a problem for background writeback (as
the PD controller keys off of it) and also confusing for users.

This is also prep work for making background writeback aware of raid5/6
stripes.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:16 -07:00
Kent Overstreet
6ded34d1a5 bcache: Improve lazy sorting
The old lazy sorting code was kind of hacky - rewrite in a way that
mathematically makes more sense; the idea is that the size of the sets
of keys in a btree node should increase by a more or less fixed ratio
from smallest to biggest.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:16 -07:00
Kent Overstreet
85b1492ee1 bcache: Rip out pkey()/pbtree()
Old gcc doesnt like the struct hack, and it is kind of ugly. So finish
off the work to convert pr_debug() statements to tracepoints, and delete
pkey()/pbtree().

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:15 -07:00
Kent Overstreet
c37511b863 bcache: Fix/revamp tracepoints
The tracepoints were reworked to be more sensible, and fixed a null
pointer deref in one of the tracepoints.

Converted some of the pr_debug()s to tracepoints - this is partly a
performance optimization; it used to be that with DEBUG or
CONFIG_DYNAMIC_DEBUG pr_debug() was an empty macro; but at some point it
was changed to an empty inline function.

Some of the pr_debug() statements had rather expensive function calls as
part of the arguments, so this code was getting run unnecessarily even
on non debug kernels - in some fast paths, too.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:15 -07:00
Kent Overstreet
5794351146 bcache: Refactor btree io
The most significant change is that btree reads are now done
synchronously, instead of asynchronously and doing the post read stuff
from a workqueue.

This was originally done because we can't block on IO under
generic_make_request(). But - we already have a mechanism to punt cache
lookups to workqueue if needed, so if we just use that we don't have to
deal with the complexity of doing things asynchronously.

The main benefit is this makes the locking situation saner; we can hold
our write lock on the btree node until we're finished reading it, and we
don't need that btree_node_read_done() flag anymore.

Also, for writes, btree_write() was broken out into btree_node_write()
and btree_leaf_dirty() - the old code with the boolean argument was dumb
and confusing.

The prio_blocked mechanism was improved a bit too, now the only counter
is in struct btree_write, we don't mess with transfering a count from
struct btree anymore.

This required changing garbage collection to block prios at the start
and unblock when it finishes, which is cleaner than what it was doing
anyways (the old code had mostly the same effect, but was doing it in a
convoluted way)

And the btree iter btree_node_read_done() uses was converted to a real
mempool.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:14 -07:00
Kent Overstreet
119ba0f828 bcache: Convert allocator thread to kthread
Using a workqueue when we just want a single thread is a bit silly.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:13 -07:00
Gabriel de Perthuis
a9dd53adbb bcache: Warn when a device is already registered.
Signed-off-by: Gabriel de Perthuis <g2p.code+bcache@gmail.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:08:52 -07:00
Kent Overstreet
bbc77aa7fb bcache: fix a spurious gcc complaint, use scnprintf
An old version of gcc was complaining about using a const int as the
size of a stack allocated array. Which should be fine - but using
ARRAY_SIZE() is better, anyways.

Also, refactor the code to use scnprintf().

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:06:33 -07:00
Kumar Amit Mehta
5c694129c8 md: bcache: io.c: fix a potential NULL pointer dereference
bio_alloc_bioset returns NULL on failure. This fix adds a missing check
for potential NULL pointer dereferencing.

Signed-off-by: Kumar Amit Mehta <gmate.amit@gmail.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:06:19 -07:00
Phil Viana
48a73025cb md: bcache: Fixed a typo with the word 'arithmetic'
The word 'arithmetic' was typed as 'arithmatic'

Signed-off-by: Phil Viana <phillip.l.viana@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-06-18 13:41:16 +02:00
Kent Overstreet
f59fce847f bcache: Fix error handling in init code
This code appears to have rotted... fix various bugs and do some
refactoring.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-05-15 00:48:14 -07:00
Paul Bolle
bbb1c3b5ae bcache: drop "select CLOSURES"
The Kconfig entry for BCACHE selects CLOSURES. But there's no Kconfig
symbol CLOSURES. That symbol was used in development versions of bcache,
but was removed when the closures code was no longer provided as a
kernel library. It can safely be dropped.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
2013-05-15 00:42:51 -07:00
Emil Goode
867e116206 bcache: Fix incompatible pointer type warning
The function pointer release in struct block_device_operations
should point to functions declared as void.

Sparse warnings:

drivers/md/bcache/super.c:656:27: warning:
	incorrect type in initializer (different base types)
	drivers/md/bcache/super.c:656:27:
	expected void ( *release )( ... )
	drivers/md/bcache/super.c:656:27:
	got int ( static [toplevel] *<noident> )( ... )

drivers/md/bcache/super.c:656:2: warning:
	initialization from incompatible pointer type [enabled by default]

drivers/md/bcache/super.c:656:2: warning:
	(near initialization for ‘bcache_ops.release’) [enabled by default]

Signed-off-by: Emil Goode <emilgoode@gmail.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-05-15 00:42:50 -07:00
Kent Overstreet
ee66850642 bcache: Use bd_link_disk_holder()
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-30 19:14:43 -07:00
Kent Overstreet
86b26b824c bcache: Allocator cleanup/fixes
The main fix is that bch_allocator_thread() wasn't waiting on
garbage collection to finish (if invalidate_buckets had set
ca->invalidate_needs_gc); we need that to make sure the allocator
doesn't spin and potentially block gc from finishing.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-30 19:14:40 -07:00
Kent Overstreet
8abb2a5dba bcache: Make sure blocksize isn't smaller than device blocksize
Sanity check to make sure we don't end up doing IO the device doesn't
support.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-24 13:07:39 -07:00
Kent Overstreet
a09ded8edf bcache: Fix merge_bvec_fn usage for when it modifies the bvm
Stacked md devices reuse the bvm for the subordinate device, causing
problems...

Reported-by: Michael Balser <michael.balser@profitbricks.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-22 14:44:24 -07:00
Kent Overstreet
1545f13730 bcache: Correctly check against BIO_MAX_PAGES
bch_bio_max_sectors() was checking against BIO_MAX_PAGES as if the limit
was for the total bytes in the bio, not the number of segments.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-20 17:57:42 -07:00
Kent Overstreet
bca97adaf5 bcache: Hack around stuff that clones up to bi_max_vecs
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-20 17:57:41 -07:00
Kent Overstreet
4f0fd955cd bcache: Set ra_pages based on backing device's ra_pages
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-20 17:57:26 -07:00
Kent Overstreet
2903381fce bcache: Take data offset from the bdev superblock.
Add a new superblock version, and consolidate related defines.

Signed-off-by: Gabriel de Perthuis <g2p.code+bcache@gmail.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-20 17:56:12 -07:00
Kent Overstreet
cef5279735 bcache: Disable broken btree fuzz tester
Reported-by: <sasha.levin@oracle.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-08 13:33:49 -07:00
Kent Overstreet
91bbcfc361 bcache: Fix a format string overflow
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-08 13:33:49 -07:00
Kent Overstreet
8ef747909c bcache: Fix a minor memory leak on device teardown
Reported-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-08 13:33:48 -07:00
Kent Overstreet
cc0f4eaa61 bcache: Use WARN_ONCE() instead of __WARN()
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-08 13:33:48 -07:00
Geert Uytterhoeven
cd953ed036 bcache: Add missing #include <linux/prefetch.h>
m68k/allmodconfig:

drivers/md/bcache/bset.c: In function ‘bset_search_tree’:
drivers/md/bcache/bset.c:727: error: implicit declaration of function ‘prefetch’

drivers/md/bcache/btree.c: In function ‘bch_btree_node_get’:
drivers/md/bcache/btree.c:933: error: implicit declaration of function ‘prefetch’

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-08 13:33:48 -07:00
Kent Overstreet
c19ed23a0b bcache: Sparse fixes
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-08 13:33:48 -07:00
Kent Overstreet
169ef1cf61 bcache: Don't export utility code, prefix with bch_
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-28 12:50:55 -06:00
Kent Overstreet
29177b8966 bcache: Fix for the build fixes
Commit 82a84eaf7e51ba3da0c36cbc401034a4e943492d left a return 0 in
closure_debug_init(). Whoops.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-25 19:36:39 -06:00
Kent Overstreet
b1a67b0f4c bcache: Style/checkpatch fixes
Took out some nested functions, and fixed some more checkpatch
complaints.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-25 13:06:13 -06:00
Kent Overstreet
07e86ccb54 bcache: Build fixes from test robot
config: make ARCH=i386 allmodconfig

All error/warnings:

   drivers/md/bcache/bset.c: In function 'bch_ptr_bad':
>> drivers/md/bcache/bset.c:164:2: warning: format '%li' expects argument of type 'long int', but argument 4 has type 'size_t' [-Wformat]
--
   drivers/md/bcache/debug.c: In function 'bch_pbtree':
>> drivers/md/bcache/debug.c:86:4: warning: format '%li' expects argument of type 'long int', but argument 4 has type 'size_t' [-Wformat]
--
   drivers/md/bcache/btree.c: In function 'bch_btree_read_done':
>> drivers/md/bcache/btree.c:245:8: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'size_t' [-Wformat]
--
   drivers/md/bcache/closure.o: In function `closure_debug_init':
>> (.init.text+0x0): multiple definition of `init_module'
>> drivers/md/bcache/super.o:super.c:(.init.text+0x0): first defined here

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-25 13:06:13 -06:00
Kent Overstreet
cafe563591 bcache: A block layer cache
Does writethrough and writeback caching, handles unclean shutdown, and
has a bunch of other nifty features motivated by real world usage.

See the wiki at http://bcache.evilpiepirate.org for more.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-03-23 16:11:31 -07:00