When shrinking the filesystem, segments to be truncated must be test
if they are busy or not, and unneeded sufile block should be deleted.
This adds routines for the truncation.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
After resizing the filesystem, the secondary super block must be moved
to a new location. This adds a helper function for this.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This adds a new ioctl command which limits range of segment to be
allocated. This is intended to gather data whithin a range of the
partition before shrinking the filesystem, or to control new log
location for some purpose.
If a range is specified by the ioctl, segment allocator of nilfs tries
to allocate new segments from the range unless no free segments are
available there.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The super root block is newly-allocated each time it is written back
to disk, so unused portion of the block should be cleared.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The size of super root structure depends on inode size, so
NILFS_SR_BYTES macro should be a function of the inode size. This
fixes the issue.
Even though a different size value will be written for a possible
future filesystem with extended inode, but fortunately this does not
break disk format compatibility.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Previously, nilfs was cloning pages for mmapped region to freeze their
data and ensure consistency of checksum during writeback cycles. A
private page allocator was used for this page cloning. But, we no
longer need to do that since clear_page_dirty_for_io function sets up
pte so that vm_ops->page_mkwrite function is called right before the
mmapped pages are modified and nilfs_page_mkwrite function can safely
wait for the pages to be written back to disk.
So, this stops making a copy of mmapped pages during writeback, and
eliminates the private page allocation and deallocation functions from
nilfs.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Merge list_del() + list_add_tail() to list_move_tail().
Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
After having applied commit 9954e7af14 ("nilfs2: add free
entries count only if clear bit operation succeeded"), a free routine
of nilfs came to fall into an infinite loop, outputting the same
message endlessly:
nilfs_palloc_freev: entry number 29497 already freed
nilfs_palloc_freev: entry number 29497 already freed
nilfs_palloc_freev: entry number 29497 already freed
nilfs_palloc_freev: entry number 29497 already freed
nilfs_palloc_freev: entry number 29497 already freed ...
That patch broke the routine so that a loop counter is never updated
in an abnormal state. This fixes the regression.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
With the ->sync_page() hook gone, we have a few users that
add their own static address_space_operations without any
functions defined.
fs/inode.c already has an empty_aops that it uses for init
purposes. Lets export that and use it in the places where
an otherwise empty aops was defined.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
From the result of a function test of mmap, mmap write to shared pages
turned out to be broken for hole blocks. It doesn't write out filled
blocks and the data will be lost after umount. This is due to a bug
that the target file is not queued for log writer when filling hole
blocks.
Also, nilfs_page_mkwrite function exits normal code path even after
successfully filled hole blocks due to a change of block_page_mkwrite
function; just after nilfs was merged into the mainline,
block_page_mkwrite() started to return VM_FAULT_LOCKED instead of zero
by the patch "mm: close page_mkwrite races" (commit:
b827e496c8). The current nilfs_page_mkwrite() is not handling
this value properly.
This corrects nilfs_page_mkwrite() and will resolve the data loss
problem in mmap write.
[This should be applied to every kernel since 2.6.30 but a fix is
needed for 2.6.37 and prior kernels]
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: stable <stable@kernel.org> [2.6.38]
* 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits)
Documentation/iostats.txt: bit-size reference etc.
cfq-iosched: removing unnecessary think time checking
cfq-iosched: Don't clear queue stats when preempt.
blk-throttle: Reset group slice when limits are changed
blk-cgroup: Only give unaccounted_time under debug
cfq-iosched: Don't set active queue in preempt
block: fix non-atomic access to genhd inflight structures
block: attempt to merge with existing requests on plug flush
block: NULL dereference on error path in __blkdev_get()
cfq-iosched: Don't update group weights when on service tree
fs: assign sb->s_bdi to default_backing_dev_info if the bdi is going away
block: Require subsystems to explicitly allocate bio_set integrity mempool
jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
fs: make fsync_buffers_list() plug
mm: make generic_writepages() use plugging
blk-cgroup: Add unaccounted time to timeslice_used.
block: fixup plugging stubs for !CONFIG_BLOCK
block: remove obsolete comments for blkdev_issue_zeroout.
blktrace: Use rq->cmd_flags directly in blk_add_trace_rq.
...
Fix up conflicts in fs/{aio.c,super.c}
And give it a kernel-doc comment.
[akpm@linux-foundation.org: btrfs changed in linux-next]
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As a preparation for removing ext2 non-atomic bit operations from
asm/bitops.h. This converts ext2 non-atomic bit operations to
little-endian bit operations.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the plugging now being explicitly controlled by the
submitter, callers need not pass down unplugging hints
to the block layer. If they want to unplug, it's because they
manually plugged on their own - in which case, they should just
unplug at will.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This directly uses sb->s_fs_info to keep a nilfs filesystem object and
fully removes the intermediate nilfs_sb_info structure. With this
change, the hierarchy of on-memory structures of nilfs will be
simplified as follows:
Before:
super_block
-> nilfs_sb_info
-> the_nilfs
-> cptree --+-> nilfs_root (current file system)
+-> nilfs_root (snapshot A)
+-> nilfs_root (snapshot B)
:
-> nilfs_sc_info (log writer structure)
After:
super_block
-> the_nilfs
-> cptree --+-> nilfs_root (current file system)
+-> nilfs_root (snapshot A)
+-> nilfs_root (snapshot B)
:
-> nilfs_sc_info (log writer structure)
The reason why we didn't design so from the beginning is because the
initial shape also differed from the above. The early hierachy was
composed of "per-mount-point" super_block -> nilfs_sb_info pairs and a
shared nilfs object. On the kernel 2.6.37, it was changed to the
current shape in order to unify super block instances into one per
device, and this cleanup became applicable as the result.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Removes sci->sc_sbi which is a back pointer to nilfs_sb_info struct
from log writer object (nilfs_sc_info).
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Log writer is held by the nilfs_sb_info structure. This moves it into
nilfs object and replaces all uses of NILFS_SC() accessor.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Moves s_next_generation counter and a spinlock protecting it to nilfs
object from nilfs_sb_info structure.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Moves s_inode_lock spinlock and s_dirty_files list to nilfs object
from nilfs_sb_info structure.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This moves four parameter variables on nilfs_sb_info s_resuid,
s_resgid, s_interval and s_watermark to the nilfs object.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This records the number of used blocks per checkpoint in each
checkpoint entry of cpfile. Even though userland tools can get the
block count via nilfs_get_cpinfo ioctl, it was not updated by the
nilfs2 kernel code. This fixes the issue and makes it available for
userland tools to calculate used amount per checkpoint.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Jiro SEKIBA <jir@unicus.jp>
This is a similar change to those in ext2/ext3 codebase (commit
40a063f669 and a4ae309486, respectively).
The addition of 64k block capability in the rec_len_from_disk and
rec_len_to_disk functions added a bit of math overhead which slows
down file create workloads needlessly when the architecture cannot
even support 64k blocks. This will cut the corner.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
At present, the same warning message can be output twice when nilfs
detected a problem on super blocks:
NILFS warning: broken superblock. using spare superblock.
NILFS warning: broken superblock. using spare superblock.
...
This is because these super blocks are reloaded with the block size
written in a super block if it differs from the first block size, but
this repetition looks somewhat confusing. So, we hint at what is
going on by appending block size information to those messages.
Reported-by: Wakko Warner <wakko@animx.eu.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The current FS_IOC_GETFLAGS/SETFLAGS/GETVERSION will fail if
application is 32 bit and kernel is 64 bit.
This issue is avoidable by adding compat_ioctl method.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Add support for the standard attributes set via chattr and read via
lsattr. These attributes are already in the flags value in the nilfs2
inode, but currently we don't have any ioctl commands that expose them
to the userland.
Collaterally, this adds the FS_IOC_GETVERSION ioctl for getting
i_generation, which allows users to list the file's generation number
with "lsattr -v".
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Nilfs has few rectrictions on which flags may be set on which inodes
like ext2/3/4 filesystems used to be. Specifically DIRSYNC may only
be set on directories and IMMUTABLE and APPEND may not be set on
links. Tighten that to disallow TOPDIR being set on non-directories
and only NODUMP and NOATIME to be set on non-regular file,
non-directories.
This introduces a flags masking function like those of extN and uses
it during inode creation.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
At present, nilfs marks S_NOATIME flag on all inodes. This restricts
nilfs_set_inode_flags function so that it marks S_NOATIME only if a
given inode has an FS_NOATIME_FL flag.
Although nilfs does not support atime yet, touch_atime() still safely
returns on IS_NOATIME check since MS_NOATIME is always set on sb.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Replaces uses of own inode flags (i.e. NILFS_SECRM_FL, NILFS_UNRM_FL,
NILFS_COMPR_FL, and so forth) with common inode flags, and removes the
own flag declarations.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Three functions of the current persistent object allocator,
nilfs_palloc_commit_free_entry, nilfs_palloc_abort_alloc_entry, and
nilfs_palloc_freev functions unconditionally add a counter after doing
clear bit operation on a bitmap block.
If the clear bit operation overlapped, the counter will not add up.
This fixes the issue by making the counter operations conditional.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This fixes the issue that inodes count will not add up after removal
of raw inodes fails. Hence, this prevents possible under flow of the
inodes count.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
According to the report from Jiro SEKIBA titled "regression in
2.6.37?" (Message-Id: <8739n8vs1f.wl%jir@sekiba.com>), on 2.6.37 and
later kernels, lscp command no longer displays "i" flag on checkpoints
that snapshot operations or garbage collection created.
This is a regression of nilfs2 checkpointing function, and it's
critical since it broke behavior of a part of nilfs2 applications.
For instance, snapshot manager of TimeBrowse gets to create
meaningless snapshots continuously; snapshot creation triggers another
checkpoint, but applications cannot distinguish whether the new
checkpoint contains meaningful changes or not without the i-flag.
This patch fixes the regression and brings that application behavior
back to normal.
Reported-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Jiro SEKIBA <jir@unicus.jp>
Cc: stable <stable@kernel.org> [2.6.37]
Michael Leun reported that running parallel opens on a fuse filesystem
can trigger a "kernel BUG at mm/truncate.c:475"
Gurudas Pai reported the same bug on NFS.
The reason is, unmap_mapping_range() is not prepared for more than
one concurrent invocation per inode. For example:
thread1: going through a big range, stops in the middle of a vma and
stores the restart address in vm_truncate_count.
thread2: comes in with a small (e.g. single page) unmap request on
the same vma, somewhere before restart_address, finds that the
vma was already unmapped up to the restart address and happily
returns without doing anything.
Another scenario would be two big unmap requests, both having to
restart the unmapping and each one setting vm_truncate_count to its
own value. This could go on forever without any of them being able to
finish.
Truncate and hole punching already serialize with i_mutex. Other
callers of unmap_mapping_range() do not, and it's difficult to get
i_mutex protection for all callers. In particular ->d_revalidate(),
which calls invalidate_inode_pages2_range() in fuse, may be called
with or without i_mutex.
This patch adds a new mutex to 'struct address_space' to prevent
running multiple concurrent unmap_mapping_range() on the same mapping.
[ We'll hopefully get rid of all this with the upcoming mm
preemptibility series by Peter Zijlstra, the "mm: Remove i_mmap_mutex
lockbreak" patch in particular. But that is for 2.6.39 ]
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reported-by: Michael Leun <lkml20101129@newton.leun.net>
Reported-by: Gurudas Pai <gurudas.pai@oracle.com>
Tested-by: Gurudas Pai <gurudas.pai@oracle.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
block: ensure that completion error gets properly traced
blktrace: add missing probe argument to block_bio_complete
block cfq: don't use atomic_t for cfq_group
block cfq: don't use atomic_t for cfq_queue
block: trace event block fix unassigned field
block: add internal hd part table references
block: fix accounting bug on cross partition merges
kref: add kref_test_and_get
bio-integrity: mark kintegrityd_wq highpri and CPU intensive
block: make kblockd_workqueue smarter
Revert "sd: implement sd_check_events()"
block: Clean up exit_io_context() source code.
Fix compile warnings due to missing removal of a 'ret' variable
fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
cfq-iosched: don't check cfqg in choose_service_tree()
fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
cdrom: export cdrom_check_events()
sd: implement sd_check_events()
sr: implement sr_check_events()
...
Remove kobject.h from files which don't need it, notably,
sched.h and fs.h.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
nilfs_dat_inode function was a wrapper to switch between normal dat
inode and gcdat, a clone of the dat inode for garbage collection.
This function got obsolete when the gcdat inode was removed, and now
we can access the dat inode directly from a nilfs object. So, we will
unfold the wrapper and remove it.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This removes argument for passing nilfs_sb_info structure from
nilfs_set_file_dirty and nilfs_load_inode_block functions. We can get
a pointer to the structure from inodes.
[Stephen Rothwell <sfr@canb.auug.org.au>: fix conflict with commit
b74c79e993]
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Only mount_opt member is used in the nilfs_mount_options structure,
and we can simplify it.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
nilfs_page_get_nth_block() function used in nilfs_mdt_freeze_buffer()
always returns a valid buffer head, so its validity check can be
removed.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This adds fiemap to nilfs. Two new functions, nilfs_fiemap and
nilfs_find_uncommitted_extent are added.
nilfs_fiemap() implements the fiemap inode operation, and
nilfs_find_uncommitted_extent() helps to get a range of data blocks
whose physical location has not been determined.
nilfs_fiemap() collects extent information by looping through
nilfs_bmap_lookup_contig and nilfs_find_uncommitted_extent routines.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Nilfs does not allocate new blocks on disk until they are actually
written to. To implement fiemap, we need to deal with such blocks.
To allow successive fiemap patch to distinguish mapped but unallocated
regions, this marks buffer heads of those new blocks as delayed and
clears the flag after the blocks are written to disk.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Some functions using nilfs bmap routines can wrongly return invalid
argument error (i.e. -EINVAL) that bmap returns as an internal code
for btree corruption.
This fixes the issue by catching and converting the internal EINVAL to
EIO and calling nilfs_error function inside bmap routines.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Using %pV reduces the number of printk calls and
eliminates any possible message interleaving from
other printk calls.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
RCU free the struct inode. This will allow:
- Subsequent store-free path walking patch. The inode must be consulted for
permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
to take i_lock no longer need to take sb_inode_list_lock to walk the list in
the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
page lock to follow page->mapping.
The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.
In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.
The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Make d_count non-atomic and protect it with d_lock. This allows us to ensure a
0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when
we start protecting many other dentry members with d_lock.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
On 2.6.37-rc1, garbage collection ioctl of nilfs was broken due to the
commit 263d90cefc ("nilfs2: remove own inode hash used for GC"),
and leading to filesystem corruption.
The patch doesn't queue gc-inodes for log writer if they are reused
through the vfs inode cache. Here, gc-inode is the inode which
buffers blocks to be relocated on GC. That patch queues gc-inodes in
nilfs_init_gcinode() function, but this function is not called when
they don't have I_NEW flag. Thus, some of live blocks are wrongly
overrode without being moved to new logs.
This resolves the problem by moving the gc-inode queueing to an outer
function to ensure it's done right.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
nilfs_iget_for_gc() returns an ERR_PTR() on failure and doesn't return
NULL.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
After recent blkdev_get() modifications, open_by_devnum() and
open_bdev_exclusive() are simple wrappers around blkdev_get().
Replace them with blkdev_get_by_dev() and blkdev_get_by_path().
blkdev_get_by_dev() is identical to open_by_devnum().
blkdev_get_by_path() is slightly different in that it doesn't
automatically add %FMODE_EXCL to @mode.
All users are converted. Most conversions are mechanical and don't
introduce any behavior difference. There are several exceptions.
* btrfs now sets FMODE_EXCL in btrfs_device->mode, so there's no
reason to OR it explicitly on blkdev_put().
* gfs2, nilfs2 and the generic mount_bdev() now set FMODE_EXCL in
sb->s_mode.
* With the above changes, sb->s_mode now always should contain
FMODE_EXCL. WARN_ON_ONCE() added to kill_block_super() to detect
errors.
The new blkdev_get_*() functions are with proper docbook comments.
While at it, add function description to blkdev_get() too.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Joern Engel <joern@lazybastard.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: reiserfs-devel@vger.kernel.org
Cc: xfs-masters@oss.sgi.com
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Over time, block layer has accumulated a set of APIs dealing with bdev
open, close, claim and release.
* blkdev_get/put() are the primary open and close functions.
* bd_claim/release() deal with exclusive open.
* open/close_bdev_exclusive() are combination of open and claim and
the other way around, respectively.
* bd_link/unlink_disk_holder() to create and remove holder/slave
symlinks.
* open_by_devnum() wraps bdget() + blkdev_get().
The interface is a bit confusing and the decoupling of open and claim
makes it impossible to properly guarantee exclusive access as
in-kernel open + claim sequence can disturb the existing exclusive
open even before the block layer knows the current open if for another
exclusive access. Reorganize the interface such that,
* blkdev_get() is extended to include exclusive access management.
@holder argument is added and, if is @FMODE_EXCL specified, it will
gain exclusive access atomically w.r.t. other exclusive accesses.
* blkdev_put() is similarly extended. It now takes @mode argument and
if @FMODE_EXCL is set, it releases an exclusive access. Also, when
the last exclusive claim is released, the holder/slave symlinks are
removed automatically.
* bd_claim/release() and close_bdev_exclusive() are no longer
necessary and either made static or removed.
* bd_link_disk_holder() remains the same but bd_unlink_disk_holder()
is no longer necessary and removed.
* open_bdev_exclusive() becomes a simple wrapper around lookup_bdev()
and blkdev_get(). It also has an unexpected extra bdev_read_only()
test which probably should be moved into blkdev_get().
* open_by_devnum() is modified to take @holder argument and pass it to
blkdev_get().
Most of bdev open/close operations are unified into blkdev_get/put()
and most exclusive accesses are tested atomically at the open time (as
it should). This cleans up code and removes some, both valid and
invalid, but unnecessary all the same, corner cases.
open_bdev_exclusive() and open_by_devnum() can use further cleanup -
rename to blkdev_get_by_path() and blkdev_get_by_devt() and drop
special features. Well, let's leave them for another day.
Most conversions are straight-forward. drbd conversion is a bit more
involved as there was some reordering, but the logic should stay the
same.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Brown <neilb@suse.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Alex Elder <aelder@sgi.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: dm-devel@redhat.com
Cc: drbd-dev@lists.linbit.com
Cc: Leo Chen <leochen@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Joern Engel <joern@logfs.org>
Cc: reiserfs-devel@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits)
split invalidate_inodes()
fs: skip I_FREEING inodes in writeback_sb_inodes
fs: fold invalidate_list into invalidate_inodes
fs: do not drop inode_lock in dispose_list
fs: inode split IO and LRU lists
fs: switch bdev inode bdi's correctly
fs: fix buffer invalidation in invalidate_list
fsnotify: use dget_parent
smbfs: use dget_parent
exportfs: use dget_parent
fs: use RCU read side protection in d_validate
fs: clean up dentry lru modification
fs: split __shrink_dcache_sb
fs: improve DCACHE_REFERENCED usage
fs: use percpu counter for nr_dentry and nr_dentry_unused
fs: simplify __d_free
fs: take dcache_lock inside __d_path
fs: do not assign default i_ino in new_inode
fs: introduce a per-cpu last_ino allocator
new helper: ihold()
...
To help developers and applications gain visibility into writeback
behaviour this patch adds two counters to /proc/vmstat.
# grep nr_dirtied /proc/vmstat
nr_dirtied 3747
# grep nr_written /proc/vmstat
nr_written 3618
These entries allow user apps to understand writeback behaviour over time
and learn how it is impacting their performance. Currently there is no
way to inspect dirty and writeback speed over time. It's not possible for
nr_dirty/nr_writeback.
These entries are necessary to give visibility into writeback behaviour.
We have /proc/diskstats which lets us understand the io in the block
layer. We have blktrace for more in depth understanding. We have
e2fsprogs and debugsfs to give insight into the file systems behaviour,
but we don't offer our users the ability understand what writeback is
doing. There is no way to know how active it is over the whole system, if
it's falling behind or to quantify it's efforts. With these values
exported users can easily see how much data applications are sending
through writeback and also at what rates writeback is processing this
data. Comparing the rates of change between the two allow developers to
see when writeback is not able to keep up with incoming traffic and the
rate of dirty memory being sent to the IO back end. This allows folks to
understand their io workloads and track kernel issues. Non kernel
engineers at Google often use these counters to solve puzzling performance
problems.
Patch #4 adds a pernode vmstat file with nr_dirtied and nr_written
Patch #5 add writeback thresholds to /proc/vmstat
Currently these values are in debugfs. But they should be promoted to
/proc since they are useful for developers who are writing databases
and file servers and are not debugging the kernel.
The output is as below:
# grep threshold /proc/vmstat
nr_pages_dirty_threshold 409111
nr_pages_dirty_background_threshold 818223
This patch:
This allows code outside of the mm core to safely manipulate page
writeback state and not worry about the other accounting. Not using these
routines means that some code will lose track of the accounting and we get
bugs.
Modify nilfs2 to use interface.
Signed-off-by: Michael Rubin <mrubin@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Jiro SEKIBA <jir@unicus.jp>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (36 commits)
nilfs2: eliminate sparse warning - "context imbalance"
nilfs2: eliminate sparse warnings - "symbol not declared"
nilfs2: get rid of bdi from nilfs object
nilfs2: change license of exported header file
nilfs2: add bdev freeze/thaw support
nilfs2: accept 64-bit checkpoint numbers in cp mount option
nilfs2: remove own inode allocator and destructor for metadata files
nilfs2: get rid of back pointer to writable sb instance
nilfs2: get rid of mi_nilfs back pointer to nilfs object
nilfs2: see state of root dentry for mount check of snapshots
nilfs2: use iget for all metadata files
nilfs2: get rid of GCDAT inode
nilfs2: add routines to redirect access to buffers of DAT file
nilfs2: add routines to roll back state of DAT file
nilfs2: add routines to save and restore bmap state
nilfs2: do not allocate nilfs_mdt_info structure to gc-inodes
nilfs2: allow nilfs_clear_inode to clear metadata file inodes
nilfs2: get rid of snapshot mount flag
nilfs2: simplify life cycle management of nilfs object
nilfs2: do not allocate multiple super block instances for a device
...
insert sparse annotations to fix following sparse warning.
fs/nilfs2/segment.c:2681:3: warning: context imbalance in 'nilfs_segctor_kill_thread' - unexpected unlock
nilfs_segctor_kill_thread is only called inside sc_state_lock lock.
sparse doesn't detect the context and warn "unexpected unlock".
__acquires/__releases pretend to lock/unlock the sc_state_lock for sparse.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
change nilfs_dat_commit_free and nilfs_inode_cachep static
to fix following warnings
fs/nilfs2/super.c:72:19: warning: symbol 'nilfs_inode_cachep' was not declared. Should it be static?
fs/nilfs2/dat.c:106:6: warning: symbol 'nilfs_dat_commit_free' was not declared. Should it be static?
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Nilfs now can use sb->s_bdi to get backing_dev_info, so we use it
instead of ns_bdi on the nilfs object and remove ns_bdi.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Nilfs hasn't supported the freeze/thaw feature because it didn't work
due to the peculiar design that multiple super block instances could
be allocated for a device. This limitation was removed by the patch
"nilfs2: do not allocate multiple super block instances for a device".
So now this adds the freeze/thaw support to nilfs.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The current implementation doesn't mount snapshots with checkpoint
numbers larger than INT_MAX since it uses match_int() for parsing
"cp=" mount option.
This uses simple_strtoull() for the conversion to resolve the issue.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This finally removes own inode allocator and destructor functions for
metadata files. Several routines, nilfs_mdt_new(),
nilfs_mdt_new_common(), nilfs_mdt_clear(), nilfs_mdt_destroy(), and
nilfs_alloc_inode_common() will be gone.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Nilfs object holds a back pointer to a writable super block instance
in nilfs->ns_writer, and this became eliminable since sb is now made
per device and all inodes have a valid pointer to it.
This deletes the ns_writer pointer and a reader/writer semaphore
protecting it.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This removes a back pointer to nilfs object from nilfs_mdt_info
structure that is attached to metadata files.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
After applied the patch that unified sb instances, root dentry of
snapshots can be left in dcache even after their trees are unmounted.
The orphan root dentry/inode keeps a root object, and this causes
false positive of nilfs_checkpoint_is_mounted function.
This resolves the issue by having nilfs_checkpoint_is_mounted test
whether the root dentry is busy or not.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This makes use of iget5_locked to allocate or get inode for metadata
files to stop using own inode allocator.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This applies prepared rollback function and redirect function of
metadata file to DAT file, and eliminates GCDAT inode.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
During garbage collection (GC), DAT file, which converts virtual block
number to real block number, may return disk block number that is not
yet written to the device.
To avoid access to unwritten blocks, the current implementation stores
changes to the caches of GCDAT during GC and atomically commit the
changes into the DAT file after they are written to the device.
This patch, instead, adds a function that makes a copy of specified
buffer and stores it in nilfs_shadow_map, and a function to get the
backup copy as needed (nilfs_mdt_freeze_buffer and
nilfs_mdt_get_frozen_buffer respectively).
Before DAT changes block number in an entry block, it makes a copy and
redirect access to the buffer so that address conversion function
(i.e. nilfs_dat_translate) refers to the old address saved in the
copy.
This patch gives requisites for such redirection.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This adds optional function to metadata files which makes a copy of
bmap, page caches, and b-tree node cache, and rolls back to the copy
as needed.
This enhancement is intended to displace gcdat inode that provides a
similar function in a different way.
In this patch, nilfs_shadow_map structure is added to store a copy of
the foregoing states. nilfs_mdt_setup_shadow_map relates this
structure to a metadata file. And, nilfs_mdt_save_to_shadow_map() and
nilfs_mdt_restore_from_shadow_map() provides save and restore
functions respectively. Finally, nilfs_mdt_clear_shadow_map() clears
states of nilfs_shadow_map.
The copy of b-tree node cache and page cache is made by duplicating
only dirty pages into corresponding caches in nilfs_shadow_map. Their
restoration is done by clearing dirty pages from original caches and
by copying dirty pages back from nilfs_shadow_map.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This adds routines to save and restore the state of bmap structure.
The bmap state is stored in a given nilfs_bmap_store object.
These routines will be used to roll back the state of dat inode
without using gcdat inode.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
GC-inode now doesn't need the nilfs_mdt_info structure and there is no
reason that it is a sort of metadata files.
This stops the allocation and makes them not dependent on metadata
file routines.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Allows clear inode function (nilfs_clear_inode) to handle metadata
files that uses bitmap-based object alloctor. DAT and ifile
correspond to this.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This stops pre-allocating nilfs object in nilfs_get_sb routine, and
stops managing its life cycle by reference counting.
nilfs_find_or_create_nilfs() function, nilfs->ns_mount_mutex,
nilfs_objects list, and the reference counter will be removed through
the simplification.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This stops allocating multiple super block instances for a device.
All snapshots and a current mode mount (i.e. latest tree) will be
controlled with nilfs_root objects that are kept within an sb
instance.
nilfs_get_sb() is rewritten so that it always has a root object for
the latest tree and snapshots make additional root objects.
The root dentry of the latest tree is binded to sb->s_root even if it
isn't attached on a directory. Root dentries of snapshots or the
latest tree are binded to mnt->mnt_root on which they are mounted.
With this patch, nilfs_find_sbinfo() function, nilfs->ns_supers list,
and nilfs->ns_current back pointer, are deleted. In addition,
init_nilfs() and load_nilfs() are simplified since they will be called
once for a device, not repeatedly called for mount points.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This splits the code to allocate root dentry into a separate routine
for convenience in successive changes.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Snapshots of nilfs are read-only.
After super block instances (sb) will be unified, nilfs will need to
check write access by a way other than implicit test with
IS_RDONLY(inode). This is because IS_RDONLY() refers to MS_RDONLY bit
of inode->i_sb->s_flags and it will become inaccurate after the
unification of sb.
To prepare for the issue, this uses i_op->permission to deny write
access to inodes in snapshots.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This rewrites nilfs_checkpoint_is_mounted() function so that it
decides whether a checkpoint is mounted by whether the corresponding
root object is found in checkpoint tree.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This rewrites functions using ifile so that they get ifile from
nilfs_root object, and will remove sbi->s_ifile. Some functions that
don't know the root object are extended to receive it from caller.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The previous export operations cannot handle multiple versions of
a filesystem if they belong to the same sb instance.
This adds a new type of file handle and extends export operations so
that they can get the inode specified by a checkpoint number as well
as an inode number and a generation number.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This puts a pointer to nilfs_root object in the private part of
on-memory inode, and makes nilfs_iget function pick up the inode with
the same root object.
Non-root inodes inherit its nilfs_root object from parent inode. That
of the root inode is allocated through nilfs_attach_checkpoint()
function.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
To hold multiple versions of a filesystem in one sb instance, a new
on-memory structure is necessary to handle one or more checkpoints.
This adds a red-black tree of checkpoints to nilfs object, and adds
lookup and create functions for them.
Each checkpoint is represented by "nilfs_root" structure, and this
structure has rb_node to configure the rb-tree.
The nilfs_root object is identified with a checkpoint number. For
each snapshot, a nilfs_root object is allocated and the checkpoint
number of snapshot is assigned to it. For a regular mount
(i.e. current mode mount), NILFS_CPTREE_CURRENT_CNO constant is
assigned to the corresponding nilfs_root object.
Each nilfs_root object has an ifile inode and some counters. These
items will displace those of nilfs_sb_info structure in successive
patches.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This uses inode hash function that vfs provides instead of the own
hash table for caching gc inodes. This finally removes the own inode
hash from nilfs.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This separates a part of initialization code of metadata file inode,
and makes it available from the nilfs iget function that a later patch
will add to.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This uses iget5_locked instead of iget_locked so that gc cache can
look up inodes with an inode number and an optional checkpoint number.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
On-memory inode structures of nilfs have a member "i_cno" which stores
a checkpoint number related to the inode. For gc-inodes, this field
indicates version of data each gc-inode caches for GC. Log writer
temporarily uses "i_cno" to transfer the latest checkpoint number.
This stops the latter use and lets only gc-inodes use it.
The purpose of this patch is to allow the successive change use
"i_cno" for inode lookup.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This allows sop->dirty_inode callback function (nilfs_dirty_inode) to
handle metadata file inodes.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The current nilfs_destroy_inode() doesn't handle metadata file inodes
including gc inodes (dummy inodes used for garbage collection).
This allows nilfs_destroy_inode() to destroy inodes of metadata files.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
