Commit Graph

41 Commits

Author SHA1 Message Date
Ryusuke Konishi
1cb0c924fa nilfs2: wait for discard to finish
nilfs_discard_segment() doesn't wait for completion of discard
requests.  This specifies BLKDEV_IFL_WAIT flag when calling
blkdev_issue_discard() in order to fix the sync failure.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Christoph Hellwig <hch@lst.de>
2010-08-19 00:11:06 +09:00
Ryusuke Konishi
ea1a16f716 nilfs2: fix false warning saying one of two super blocks is broken
After applying commit b2ac86e1, the following message got appeared
after unclean shutdown:

> NILFS warning: broken superblock. using spare superblock.

This turns out to be a false message due to the change which updates
two super blocks alternately.  The secondary super block now can be
selected if it's newer than the primary one.

This kills the false warning by suppressing it if another super block
is not actually broken.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-08-16 11:08:36 +09:00
Ryusuke Konishi
89c0fd014d nilfs2: reject filesystem with unsupported block size
This inserts sanity check that refuses to mount a filesystem with
unsupported block size.

Previously, kernel code of nilfs was looking only limitation of
devices though mkfs.nilfs2 limits the range of block sizes; there was
no check that prevents rec_len overflow with larger block sizes.

With this change, block sizes larger than 64KB or smaller than 1KB
will get rejected explicitly by kernel.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-25 23:29:21 +09:00
Ryusuke Konishi
c5ca48aabe nilfs2: reject incompatible filesystem
This forces nilfs to check compatibility of feature flags so as to
reject a filesystem with unknown features when it mounts or remounts
the filesystem.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:16 +09:00
Ryusuke Konishi
325020477a nilfs2: do not update log cursor for small change
Super blocks of nilfs are periodically overwritten in order to record
the recent log position.  This shortens recovery time after unclean
unmount, but the current implementation performs the update even for a
few blocks of change.  If the filesystem gets small changes slowly and
continually, super blocks may be updated excessively.

This moderates the issue by skipping update of log cursor if it does
not cross a segment boundary.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:11 +09:00
Ryusuke Konishi
6c12516083 nilfs2: implement fallback for super root search
Although nilfs redundantly uses two super blocks and each may point to
different position on log, the current version of nilfs does not try
fallback to the spare super block when it doesn't find any valid log
at the position that the primary super block points to.

This has been a cause of mount failures due to write order reversals
on barrier less block devices.

This inserts fallback code in error path of nilfs_search_super_root
routine to resolve the mount failure problem.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:11 +09:00
Ryusuke Konishi
843d63baa5 nilfs2: separate setup of log cursor from init_nilfs
This separates a setup routine of log cursor from init_nilfs().  The
routine, nilfs_store_log_cursor, reads the last position of the log
containing a super root, and initializes relevant state on the nilfs
object.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:11 +09:00
Jiro SEKIBA
b2ac86e1a8 nilfs2: sync super blocks in turns
This will sync super blocks in turns instead of syncing duplicate
super blocks at the time.  This will help searching valid super root
when super block is written into disk before log is written, which is
happen when barrier-less block devices are unmounted uncleanly.  In
the situation, old super block likely points to valid log.

This patch introduces ns_sbwcount member to the nilfs object and adds
nilfs_sb_will_flip() function; ns_sbwcount counts how many times super
blocks write back to the disk.  And, nilfs_sb_will_flip() decides
whether flipping required or not based on the count of ns_sbwcount to
sync super blocks asymmetrically.

The following functions are also changed:

 - nilfs_prepare_super(): flips super blocks according to the
   argument.  The argument is calculated by nilfs_sb_will_flip()
   function.

 - nilfs_cleanup_super(): sets "clean" flag to both super blocks if
   they point to the same checkpoint.

To update both of super block information, caller of
nilfs_commit_super must set the information on both super blocks.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:11 +09:00
Ryusuke Konishi
7ecaa46cfe nilfs2: add nilfs_cleanup_super
This function write out filesystem state to super blocks in order to
share the same cleanup work.  This is a preparation for making super
block writeback alternately.

Cc: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:10 +09:00
Ryusuke Konishi
57a4bfc486 nilfs2: get rid of ns_free_segments_count
This counter is unused.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:09 +09:00
Ryusuke Konishi
aee5ce2f57 nilfs2: rename nilfs_recover_logical_segments function
The function name of nilfs_recover_logical_segments makes no sense.
This changes the name into nilfs_salvage_orphan_logs to clarify the
role of the function.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:09 +09:00
Ryusuke Konishi
8b94025c00 nilfs2: refactor recovery logic routines
Most functions in recovery code take an argument of a super block
instance or a nilfs_sb_info struct for convenience sake.

This replaces them aggressively with a nilfs object by applying
__bread and __breadahead against routines using sb_bread and
sb_breadahead.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:08 +09:00
Ryusuke Konishi
92c60ccaf3 nilfs2: add blocksize member to nilfs object
This stores blocksize in nilfs objects for the successive refactoring
of recovery logic.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:08 +09:00
Jens Axboe
ee9a3607fb Merge branch 'master' into for-2.6.35
Conflicts:
	fs/ext3/fsync.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-05-21 21:27:26 +02:00
Ryusuke Konishi
25294d8c37 nilfs2: use checkpoint number instead of timestamp to select super block
Nilfs maintains two super blocks, and selects the new one on mount
time if they both have valid checksums and their timestamps differ.

However, this has potential for mis-selection since the system clock
may be rewinded and the resolution of the timestamps is not high.

Usually this doesn't become an issue because both super blocks are
updated at the same time when the file system is unmounted.  Even if
the file system wasn't unmounted cleanly, the roll-forward recovery
will find the proper log which stores the latest super root.  Thus,
the issue can appear only if update of one super block fails and the
clock happens to be rewinded.

This fixes the issue by using checkpoint numbers instead of timestamps
to pick the super block storing the location of the latest log.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10 11:32:32 +09:00
Stephen Rothwell
6a47dc1418 nilfs: fix breakage caused by barrier flag changes
After merging the block tree, today's linux-next build (powerpc ppc64_defconfig)
failed like this:

fs/nilfs2/the_nilfs.c: In function 'nilfs_discard_segments':
fs/nilfs2/the_nilfs.c:673: error: 'DISCARD_FL_BARRIER' undeclared (first use in this function)

Caused by commit fbd9b09a17 ("blkdev:
generalize flags for blkdev_issue_fn functions") interacting with commit
e902ec9906 ("nilfs2: issue discard request
after cleaning segments") (which netered Linus' tree on about March 4 -
before v2.6.34-rc1).

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-29 09:32:00 +02:00
Ryusuke Konishi
c91cea11df nilfs2: remove whitespaces before quoted newlines
This kills the following checkpatch warnings:

 WARNING: unnecessary whitespace before a quoted newline
 : FILE: super.c:869:
 +     	           "remount to a different snapshot. \n",

 WARNING: unnecessary whitespace before a quoted newline
 : FILE: the_nilfs.c:389:
 +     	    printk(KERN_ERR "NILFS: too short segment. \n");

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-03-14 10:29:51 +09:00
Jiro SEKIBA
e902ec9906 nilfs2: issue discard request after cleaning segments
This adds a function to send discard requests for given array of
segment numbers, and calls the function when garbage collection
succeeded.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-13 12:26:02 +09:00
Ryusuke Konishi
0234576d04 nilfs2: add norecovery mount option
This adds "norecovery" mount option which disables temporal write
access to read-only mounts or snapshots during mount/recovery.
Without this option, write access will be even performed for those
types of mounts; the temporal write access is needed to mount root
file system read-only after an unclean shutdown.

This option will be helpful when user wants to prevent any write
access to the device.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Eric Sandeen <sandeen@redhat.com>
2009-11-20 10:05:52 +09:00
Ryusuke Konishi
a057d2c011 nilfs2: add helper to get if volume is in a valid state
This adds a helper function, nilfs_valid_fs() which returns if nilfs
is in a valid state or not.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:52 +09:00
Ryusuke Konishi
f50a4c8149 nilfs2: move recovery completion into load_nilfs function
Although mount recovery of nilfs is integrated in load_nilfs()
procedure, the completion of recovery was isolated from the procedure
and performed at the end of the fill_super routine.

This was somewhat confusing since the recovery is needed for the nilfs
object, not for a super block instance.

To resolve the inconsistency, this will integrate the recovery
completion into load_nilfs().

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:52 +09:00
Ryusuke Konishi
ef7d4757a5 nilfs2: simplify nilfs_sufile_get_ncleansegs function
Previously, this function took an status code to return possible error
codes.  The ("nilfs2: add local variable to cache the number of clean
segments") patch removed the possibility to return errors.

So, this simplifies the function definition to make it directly return
the number of clean segments.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:49 +09:00
Ryusuke Konishi
fd66c0d5c3 nilfs2: hide nilfs_mdt_clear calls in nilfs_mdt_destroy
This will hide a function call of nilfs_mdt_clear() in
nilfs_mdt_destroy().

This ensures nilfs_mdt_destroy() to do cleanup jobs included in
nilfs_mdt_clear().

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:48 +09:00
Ryusuke Konishi
8707df3847 nilfs2: separate read method of meta data files on super root block
Will displace nilfs_mdt_read_inode_direct function with an individual
read method: nilfs_dat_read, nilfs_sufile_read, nilfs_cpfile_read.

This provides the opportunity to initialize local variables of each
metadata file after reading the inode.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:48 +09:00
Ryusuke Konishi
79739565e1 nilfs2: separate constructor of metadata files
This will displace nilfs_mdt_new() constructor with individual
metadata file constructors like nilfs_dat_new(), new_sufile_new(),
nilfs_cpfile_new(), and nilfs_ifile_new().

This makes it possible for each metadata file to have own
intialization code.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:48 +09:00
Ryusuke Konishi
5731e191f2 nilfs2: add size option of private object to metadata file allocator
This adds an optional "object size" argument to nilfs_mdt_new_common()
function; the argument specifies the size of private object attached
to a newly allocated metadata file inode.

This will afford space to keep local variables for meta data files.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:48 +09:00
Jens Axboe
2c96ce9f20 fs: remove bdev->bd_inode_backing_dev_info
It has been unused since it was introduced in:

commit 520808bf20e90fdbdb320264ba7dd5cf9d47dcac
Author: Andrew Morton <akpm@osdl.org>
Date:   Fri May 21 00:46:17 2004 -0700

    [PATCH] block device layer: separate backing_dev_info infrastructure

So lets just kill it.

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-16 15:16:18 +02:00
Ryusuke Konishi
7a102b0923 nilfs2: remove individual gfp constants for each metadata file
This gets rid of NILFS_CPFILE_GFP, NILFS_SUFILE_GFP, NILFS_DAT_GFP,
and NILFS_IFILE_GFP.  All of these constants refer to NILFS_MDT_GFP,
and can be removed.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:15 +09:00
Ryusuke Konishi
027d6404eb nilfs2: use semaphore to protect pointer to a writable FS-instance
will get rid of nilfs_get_writer() and nilfs_put_writer() pair used to
retain a writable FS-instance for a period.

The pair functions were making up some kind of recursive lock with a
mutex, but they became overkill since the commit
201913ed74.  Furthermore, they caused
the following lockdep warning because the mutex can be released by a
task which didn't lock it:

 =====================================
 [ BUG: bad unlock balance detected! ]
 -------------------------------------
 kswapd0/422 is trying to release lock (&nilfs->ns_writer_mutex) at:
 [<c1359ff5>] mutex_unlock+0x8/0xa
 but there are no more locks to release!

 other info that might help us debug this:
 no locks held by kswapd0/422.

 stack backtrace:
 Pid: 422, comm: kswapd0 Not tainted 2.6.31-rc4-nilfs 
 Call Trace:
  [<c1358f97>] ? printk+0xf/0x18
  [<c104fea7>] print_unlock_inbalance_bug+0xcc/0xd7
  [<c11578de>] ? prop_put_global+0x3/0x35
  [<c1050195>] lock_release+0xed/0x1dc
  [<c1359ff5>] ? mutex_unlock+0x8/0xa
  [<c1359f83>] __mutex_unlock_slowpath+0xaf/0x119
  [<c1359ff5>] mutex_unlock+0x8/0xa
  [<d1284add>] nilfs_mdt_write_page+0xd8/0xe1 [nilfs2]
  [<c1092653>] shrink_page_list+0x379/0x68d
  [<c109171b>] ? isolate_pages_global+0xb4/0x18c
  [<c1092bd2>] shrink_list+0x26b/0x54b
  [<c10930be>] shrink_zone+0x20c/0x2a2
  [<c10936b7>] kswapd+0x407/0x591
  [<c1091667>] ? isolate_pages_global+0x0/0x18c
  [<c1040603>] ? autoremove_wake_function+0x0/0x33
  [<c10932b0>] ? kswapd+0x0/0x591
  [<c104033b>] kthread+0x69/0x6e
  [<c10402d2>] ? kthread+0x0/0x6e
  [<c1003e33>] kernel_thread_helper+0x7/0x1a

This patch uses a reader/writer semaphore instead of the own lock and
kills this warning.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:13 +09:00
Linus Torvalds
9c7cb99a82 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (22 commits)
  nilfs2: support contiguous lookup of blocks
  nilfs2: add sync_page method to page caches of meta data
  nilfs2: use device's backing_dev_info for btree node caches
  nilfs2: return EBUSY against delete request on snapshot
  nilfs2: modify list of unsupported features in caveats
  nilfs2: enable sync_page method
  nilfs2: set bio unplug flag for the last bio in segment
  nilfs2: allow future expansion of metadata read out via get info ioctl
  NILFS2: Pagecache usage optimization on NILFS2
  nilfs2: remove nilfs_btree_operations from btree mapping
  nilfs2: remove nilfs_direct_operations from direct mapping
  nilfs2: remove bmap pointer operations
  nilfs2: remove useless b_low and b_high fields from nilfs_bmap struct
  nilfs2: remove pointless NULL check of bpop_commit_alloc_ptr function
  nilfs2: move get block functions in bmap.c into btree codes
  nilfs2: remove nilfs_bmap_delete_block
  nilfs2: remove nilfs_bmap_put_block
  nilfs2: remove header file for segment list operations
  nilfs2: eliminate removal list of segments
  nilfs2: add sufile function that can modify multiple segment usages
  ...
2009-06-15 09:13:49 -07:00
Ryusuke Konishi
aa7dfb8954 nilfs2: get rid of bd_mount_sem use from nilfs
This will remove every bd_mount_sem use in nilfs.

The intended exclusion control was replaced by the previous patch
("nilfs2: correct exclusion control in nilfs_remount function") for
nilfs_remount(), and this patch will replace remains with a new mutex
that this inserts in nilfs object.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:18 -04:00
Ryusuke Konishi
e59399d010 nilfs2: correct exclusion control in nilfs_remount function
nilfs_remount() changes mount state of a superblock instance.  Even
though nilfs accesses other superblock instances during mount or
remount, the mount state was not properly protected in
nilfs_remount().

Moreover, nilfs_remount() has a lock order reversal problem;
nilfs_get_sb() holds:

  1. bdev->bd_mount_sem
  2. sb->s_umount  (sget acquires)

and nilfs_remount() holds:

  1. sb->s_umount  (locked by the caller in vfs)
  2. bdev->bd_mount_sem

To avoid these problems, this patch divides a semaphore protecting
super block instances from nilfs->ns_sem, and applies it to the mount
state protection in nilfs_remount().

With this change, bd_mount_sem use is removed from nilfs_remount() and
the lock order reversal will be resolved.  And the new rw-semaphore,
nilfs->ns_super_sem will properly protect the mount state except the
modification from nilfs_error function.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:18 -04:00
Ryusuke Konishi
6dd4740662 nilfs2: simplify remaining sget() use
This simplifies the test function passed on the remaining sget()
callsite in nilfs.

Instead of checking mount type (i.e. ro-mount/rw-mount/snapshot mount)
in the test function passed to sget(), this patch first looks up the
nilfs_sb_info struct which the given mount type matches, and then
acquires the super block instance holding the nilfs_sb_info.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:18 -04:00
Ryusuke Konishi
33c8e57c86 nilfs2: get rid of sget use for acquiring nilfs object
This will change the way to obtain nilfs object in nilfs_get_sb()
function.

Previously, a preliminary sget() call was performed, and the nilfs
object was acquired from a super block instance found by the sget()
call.

This patch, instead, instroduces a new dedicated function
find_or_create_nilfs(); as the name implies, the function finds an
existent nilfs object from a global list or creates a new one if no
object is found on the device.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:17 -04:00
Ryusuke Konishi
654137dd46 nilfs2: remove header file for segment list operations
This will eliminate obsolete list operations of nilfs_segment_entry
structure which has been used to handle mutiple segment numbers.

The patch ("nilfs2: remove list of freeing segments") removed use of
the structure from the segment constructor code, and this patch
simplifies the remaining code by integrating it into recovery.c.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:09 +09:00
Martin K. Petersen
e1defc4ff0 block: Do away with the notion of hardsect_size
Until now we have had a 1:1 mapping between storage device physical
block size and the logical block sized used when addressing the device.
With SATA 4KB drives coming out that will no longer be the case.  The
sector size will be 4KB but the logical block size will remain
512-bytes.  Hence we need to distinguish between the physical block size
and the logical ditto.

This patch renames hardsect_size to logical_block_size.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:54 +02:00
Ryusuke Konishi
c2698e50e3 nilfs2: fix lockdep recursive locking warning on meta data files
This fixes the following false detection of lockdep against nilfs meta
data files:

=============================================
[ INFO: possible recursive locking detected ]
2.6.29 
---------------------------------------------
mount.nilfs2/4185 is trying to acquire lock:
 (&mi->mi_sem){----}, at: [<d0c7925b>] nilfs_sufile_get_stat+0x1e/0x105 [nilfs2]
 but task is already holding lock:
  (&mi->mi_sem){----}, at: [<d0c72026>] nilfs_count_free_blocks+0x48/0x84 [nilfs2]

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-04-13 09:53:50 +09:00
Ryusuke Konishi
e339ad31f5 nilfs2: introduce secondary super block
The former versions didn't have extra super blocks.  This improves the
weak point by introducing another super block at unused region in tail of
the partition.

This doesn't break disk format compatibility; older versions just ingore
the secondary super block, and new versions just recover it if it doesn't
exist.  The partition created by an old mkfs may not have unused region,
but in that case, the secondary super block will not be added.

This doesn't make more redundant copies of the super block; it is a future
work.

Signed-off-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>
2009-04-07 08:31:20 -07:00
Ryusuke Konishi
2c2e52fc4f nilfs2: extend nilfs_sustat ioctl struct
This adds a new argument to the nilfs_sustat structure.

The extended field allows to delete volatile active state of segments,
which was needed to protect freshly-created segments from garbage
collection but has confused code dealing with segments.  This
extension alleviates the mess and gives room for further
simplifications.

The volatile active flag is not persistent, so it's eliminable on this
occasion without affecting compatibility other than the ioctl change.

Signed-off-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>
2009-04-07 08:31:19 -07:00
Ryusuke Konishi
1088dcf4c3 nilfs2: remove timedwait ioctl command
This removes NILFS_IOCTL_TIMEDWAIT command from ioctl interface along
with the related flags and wait queue.

The command is terrible because it just sleeps in the ioctl.  I prefer
to avoid this by devising means of event polling in userland program.
By reconsidering the userland GC daemon, I found this is possible
without changing behaviour of the daemon and sacrificing efficiency.

Signed-off-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>
2009-04-07 08:31:18 -07:00
Ryusuke Konishi
8a9d2191e9 nilfs2: operations for the_nilfs core object
This adds functions on the_nilfs object, which keeps shared resources and
states among a read/write mount and snapshots mounts going individually.

the_nilfs is allocated per block device; it is created when user first
mount a snapshot or a read/write mount on the device, then it is reused
for successive mounts.  It will be freed when all mount instances on the
device are detached.

Signed-off-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>
2009-04-07 08:31:15 -07:00