Commit Graph

615 Commits

Author SHA1 Message Date
Ryusuke Konishi 9ccf56c138 nilfs2: fix function name typos in docbook comments
Fixes the following typos in docbook comments:

 nilfs_detroy_transaction_cache -> nilfs_destroy_transaction_cache
 nilfs_secgtor_start_timer -> nilfs_segctor_start_timer

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-03-14 10:29:50 +09:00
Ryusuke Konishi 6c477d44a7 nilfs2: fix discrepancy in use of static specifier
Two segbuf functions, nilfs_segbuf_write and nilfs_segbuf_wait, are
declared with the static storage class specifier, but their
implementations are not.

This fixes the discrepancy.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-03-14 10:27:27 +09:00
Linus Torvalds 0f2cc4ecd8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits)
  init: Open /dev/console from rootfs
  mqueue: fix typo "failues" -> "failures"
  mqueue: only set error codes if they are really necessary
  mqueue: simplify do_open() error handling
  mqueue: apply mathematics distributivity on mq_bytes calculation
  mqueue: remove unneeded info->messages initialization
  mqueue: fix mq_open() file descriptor leak on user-space processes
  fix race in d_splice_alias()
  set S_DEAD on unlink() and non-directory rename() victims
  vfs: add NOFOLLOW flag to umount(2)
  get rid of ->mnt_parent in tomoyo/realpath
  hppfs can use existing proc_mnt, no need for do_kern_mount() in there
  Mirror MS_KERNMOUNT in ->mnt_flags
  get rid of useless vfsmount_lock use in put_mnt_ns()
  Take vfsmount_lock to fs/internal.h
  get rid of insanity with namespace roots in tomoyo
  take check for new events in namespace (guts of mounts_poll()) to namespace.c
  Don't mess with generic_permission() under ->d_lock in hpfs
  sanitize const/signedness for udf
  nilfs: sanitize const/signedness in dealing with ->d_name.name
  ...

Fix up fairly trivial (famous last words...) conflicts in
drivers/infiniband/core/uverbs_main.c and security/tomoyo/realpath.c
2010-03-04 08:15:33 -08:00
Al Viro 072f98b463 nilfs: sanitize const/signedness in dealing with ->d_name.name
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:07:58 -05:00
Al Viro 0319003d0d nilfs really shouldn't slap struct dentry on stack...
... especially when it only needs (and initializes) .d_name of it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:07:58 -05:00
Jiro SEKIBA 0d561f12b4 nilfs2: add reader's lock for cno in nilfs_ioctl_sync
This adds reader's lock for the_nilfs->cno in nilfs_ioctl_sync,
for the_nilfs->cno should be proctected by segctor_sem when reading.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-20 21:18:19 +09:00
Jiro SEKIBA 03f29365e8 nilfs2: delete unnecessary condition in load_segment_summary
This is a trivial patch to remove unnecessary condition.

load_segment_summary() checks crc of segment_summary OR crc of whole
log data blocks based on boolean argument full_check.  However,
callers of the function pass only 1 as full_check, which means only
whole log data blocks checking code is running all the time.

This patch deletes the condition and full_check argument and also
deletes enum 'NILFS_SEG_FAIL_CHECKSUM_SEGSUM' and corresponding case
clause, for it is nolonger used anymore.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-18 20:09:03 +09:00
Ryusuke Konishi d1c6b72a72 nilfs2: move iterator to write log into segment buffer
This moves iterator to submit write requests for a series of logs into
segbuf.c, and hides nilfs_segbuf_write() and nilfs_segbuf_wait() in
the file.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-13 12:26:03 +09:00
Ryusuke Konishi e605f0a724 nilfs2: get rid of s_dirt flag use
This replaces s_dirt flag use in nilfs with a new flag added on the
nilfs object.  The s_dirt flag was used to indicate if
sop->write_super() should be called, however the current version of
nilfs does not use the callback.  Thus, it can be replaced with the
own flag.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Jiro SEKIBA <jir@unicus.jp>
2010-02-13 12:26:03 +09:00
Ryusuke Konishi dcd7618695 nilfs2: get rid of nilfs_segctor_req struct
This will clean up nilfs_segctor_req struct and the obscure request
argument passed among private methods of segment constructor.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-13 12:26:03 +09:00
Jiro SEKIBA 086d1764b2 nilfs2: delete unnecessary condition in nilfs_dat_translate
This is a trivial patch to delete unnecessary condition in nilfs_dat_translate.

nilfs_dat_translate() will asign translated address to *blocknrp if blocknrp
is not NULL.  However the condition is unneeded, because all callers of
nilfs_dat_translate() pass blocknrp properly.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-13 12:26:03 +09:00
Ryusuke Konishi fe5f171bb2 nilfs2: fix potential hang in nilfs_error on errors=remount-ro
nilfs_error() calls nilfs_detach_segment_constructor() if
errors=remount-ro option is specified, and this may lead to a hang due
to recursive locking of, for instance, nilfs->ns_segctor_sem and
others.

In this case, detaching segment constructor is not necessary because
read-only flag is set to the filesystem and further writes are
blocked.

This fixes the potential hang issue by removing the
nilfs_detach_segment_constructor() call from nilfs_error.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-13 12:26:03 +09:00
Ryusuke Konishi 7512487e6d nilfs2: use mnt_want_write in ioctls where write access is needed
A few nilfs2 ioctls need to ask for and then later release write
access to the mount in order to avoid potential write to read-only
mounts.

This adds the missing mnt_want_write and mnt_drop_write in
nilfs_ioctl_change_cpmode, nilfs_ioctl_delete_checkpoint, and
nilfs_ioctl_clean_segments.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-13 12:26:02 +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 3256a05531 nilfs2: fix potential leak of dirty data on umount
This fixes incorrect usage of nilfs_segctor_confirm() test function in
nilfs_segctor_destroy(); nilfs_segctor_confirm() returns zero if the
filesystem is not clean, so its use in nilfs_segctor_destroy() needs
inversion.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-01-31 14:57:31 +09:00
Tobias Klauser 33e189bd57 nilfs2: Storage class should be before const qualifier
The C99 specification states in section 6.11.5:

The placement of a storage-class specifier other than at the beginning
of the declaration specifiers in a declaration is an obsolescent
feature.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-12-25 13:01:50 +09:00
Jiro SEKIBA 5ee5814832 nilfs2: trivial coding style fix
This is a trivial style fix patch to mend errors/warnings
reported by "checkpatch.pl --file".

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-12-25 13:01:50 +09:00
Linus Torvalds b6e3224fb2 Revert "task_struct: make journal_info conditional"
This reverts commit e4c570c4cb, as
requested by Alexey:

 "I think I gave a good enough arguments to not merge it.
  To iterate:
   * patch makes impossible to start using ext3 on EXT3_FS=n kernels
     without reboot.
   * this is done only for one pointer on task_struct"

  None of config options which define task_struct are tristate directly
  or effectively."

Requested-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-17 13:23:24 -08:00
Al Viro a95161aaa8 switch nilfs2 to deactivate_locked_super()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:42 -05:00
Hiroshi Shimamoto e4c570c4cb task_struct: make journal_info conditional
journal_info in task_struct is used in journaling file system only.  So
introduce CONFIG_FS_JOURNAL_INFO and make it conditional.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:27 -08:00
Ryusuke Konishi a694291a62 nilfs2: separate wait function from nilfs_segctor_write
This separates wait function for submitted logs from the write
function nilfs_segctor_write().  A new list of segment buffers
"sc_write_logs" is added to hold logs under writing, and double
buffering is partially applied to hide io latency.

At this point, the double buffering is disabled for blocksize <
pagesize because page dirty flag is turned off during write and dirty
buffers are not properly collected for pages crossing over segments.

To receive full benefit of the double buffering, further refinement is
needed to move the io wait outside the lock section of log writer.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-30 21:17:52 +09:00
Ryusuke Konishi e29df395bc nilfs2: add iterator for segment buffers
This adds a few iterator functions for segment buffers to make it easy
to handle multiple series of logs.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-30 21:06:35 +09:00
Ryusuke Konishi 9c965bac16 nilfs2: hide nilfs_write_info struct in segment buffer code
Hides nilfs_write_info struct and nilfs_segbuf_prepare_write function
in segbuf.c to simplify the interface of nilfs_segbuf_write function.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-30 21:06:35 +09:00
Ryusuke Konishi 9284ad2a90 nilfs2: relocate io status variables to segment buffer
This moves io status variables in nilfs_write_info struct to
nilfs_segment_buffer struct.

This is a preparation to hide nilfs_write_info in segment buffer code.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-30 21:05:57 +09:00
Ryusuke Konishi 5f1586d0dd nilfs2: do not return io error for bio allocation failure
Previously, log writer had possibility to set an io error flag on
segments even in case of memory allocation failure.

This fixes the issue.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-29 19:59:00 +09:00
Ryusuke Konishi 0935db7477 nilfs2: use list_splice_tail or list_splice_tail_init
This applies list_splice_tail (or list_splice_tail_init) operation
instead of list_splice (or list_splice_init, respectively) to append a
new list to tail of an existing list.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-29 02:50:46 +09:00
Jiro SEKIBA abdb318b79 nilfs2: replace mark_inode_dirty as nilfs_mark_inode_dirty
Replace mark_inode_dirty() as nilfs_mark_inode_dirty()
to reduce deep function calls.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:16 +09:00
Jiro SEKIBA 3534573b58 nilfs2: delete mark_inode_dirty in nilfs_delete_entry
Delete mark_inode_dirty() in nilfs_delete_entry() to reduce duplicate
mark_inode_dirty() calls both in nilfs_rename() and nilfs_delete_entry().

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:16 +09:00
Jiro SEKIBA 58d55471cb nilfs2: delete mark_inode_dirty in nilfs_commit_chunk
Delete mark_inode_dirty() in nilfs_commit_chunk(), for callers of
nilfs_commit_chunk() will call equivalent mark_inode_dirty()
after calling nilfs_commit_chunk().

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:16 +09:00
Jiro SEKIBA 2093abf9cb nilfs2: change return type of nilfs_commit_chunk
change return type of nilfs_commit_chunk() as void from int,
for nilfs_set_file_dirty() usually does not return error.

This is an intermediate patch to reduce mark_inode_dirty() in
nilfs_commit_chunk().

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:15 +09:00
Jiro SEKIBA 4cd76c3c93 nilfs2: split nilfs_unlink as nilfs_do_unlink and nilfs_unlink
Split nilfs_unlink() to reduce nested transaction and duplicate
mark_inode_dirty() calls when calling nilfs_unlink() from nilfs_rmdir().

nilfs_do_unlink() is an actual unlink functionality which is not
in transaction and does not call mark_inode_dirty() for dentry argument.

nilfs_unlink() is a wrapper function for do_nilfs_unlink() with
transaction and mark_inode_dirty() for dentry argument.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:15 +09:00
Jiro SEKIBA 1749147276 nilfs2: delete redundant mark_inode_dirty
delete redundant mark_inode_dirty() calls

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:15 +09:00
Jiro SEKIBA 565de406e7 nilfs2: expand inode_inc_link_count and inode_dec_link_count
This is an intermidiate patch to reduce redandunt mark_inode_dirty() calls
by calling inode_inc_link_count() and inode_dec_link_count() functions.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:15 +09:00
Jiro SEKIBA 43f8bc262f nilfs2: delete mark_inode_dirty from nilfs_set_link
Delete mark_inode_dirty() from nilfs_set_link() to reduce redundant
mark_inode_dirty() calls in caller of nilfs_set_link().

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:15 +09:00
Jiro SEKIBA 9ca941d4b6 nilfs2: delete mark_inode_dirty in nilfs_new_inode
It is redundant to call mark_inode_dirty() in nilfs_new_inode() because
all caller of nilfs_new_inode() will call mark_inode_dirty()
after calling nilfs_new_inode() directly or indirectly in transaction.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-27 20:05:15 +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 050b4142c9 nilfs2: apply readahead for recovery on mount
This inserts readahead in the recovery code.  The readahead request is
issued per segment while searching the latest super root block.

This will shorten mount time after unclean unmount.  A measurement
shows the recovery time was reduced by more than 60 percent:

 e.g. real  0m11.586s -> 0m3.918s  (x 2.96)

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:51 +09:00
Ryusuke Konishi f021759d74 nilfs2: clean up get/put function of a segment usage
This eliminates obsolete nilfs_get_sufile_get_segment_usage() and
nilfs_set_sufile_segment_usage() from sufile.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:51 +09:00
Ryusuke Konishi 071ec54dd7 nilfs2: move routine to set segment usage into sufile
This adds nilfs_sufile_set_segment_usage() function in sufile to
replace direct access to the sufile metadata in log writer code.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:51 +09:00
Ryusuke Konishi 61a189e9c6 nilfs2: move routine marking segment usage dirty into sufile
This adds nilfs_sufile_mark_dirty() function in sufile to replace
nilfs_touch_segusage() function in log writer code.  This is a
preparation for the further cleanup which will move out low level
sufile operations in the log writer.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:51 +09:00
Ryusuke Konishi 70622a2091 nilfs2: insert cache operation in palloc get block routines
This implements cache operation in get block routines of palloc code:
nilfs_palloc_get_desc_block(), nilfs_palloc_get_bitmap_block(), and
nilfs_palloc_get_entry_block().

This will complete the palloc cache.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:51 +09:00
Ryusuke Konishi 49fa7a5902 nilfs2: add palloc cache to ifile
This adds the palloc cache to ifile.  The palloc cache is allocated on
the extended region of nilfs_mdt_info struct.  The struct
nilfs_ifile_info defines the extended on memory structure of ifile.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:50 +09:00
Ryusuke Konishi c3ea56c800 nilfs2: flush palloc cache before manipulating data pages of GC dat
Data pages in gcdat metadata file (i.e. the secondary DAT for GC), are
cleared or even moved back to the normal DAT when a shot of garbage
collection was done.

Buffer heads held by the palloc cache of gcdat must be cleared before
these page cache manipulation.  This adds nilfs_palloc_clear_cache()
to ensure this.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:50 +09:00
Ryusuke Konishi 8908b2f70b nilfs2: add palloc cache to dat
This adds the palloc cache to DAT file.  The palloc cache is allocated
on the extended region of nilfs_mdt_info struct.  The struct
nilfs_dat_info defines the extended on memory structure of DAT.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:50 +09:00
Ryusuke Konishi db38d5ad32 nilfs2: add cache framework for persistent object allocator
This adds setup and cleanup routines of the persistent object
allocator cache.

According to ftrace analyses, accessing buffers of the DAT file
suffers indispensable overhead many times.  To mitigate the overhead,
This introduce cache framework for the persistent object allocator
(palloc) which the DAT file and ifile are using.

struct nilfs_palloc_cache represents the cache object per metadata
file using palloc.

The cache is initialized through nilfs_palloc_setup_cache() and
destroyed by nilfs_palloc_destroy_cache(); callers of the former
function will be added to individual allocators of DAT and ifile on
successive patches.

nilfs_palloc_destroy_cache() will be called from nilfs_mdt_destroy()
if the cache is attached to a metadata file.  A companion function
nilfs_palloc_clear_cache() is provided to allow releasing buffer head
references independently with the cleanup task.  This adjunctive
function will be used before invalidating pages of metadata file with
the cache.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:50 +09:00
Ryusuke Konishi 141bbdba9c nilfs2: unfold nilfs_palloc_block_get_bitmap function
This expands a trivial address calculation in the function into its
every callsite. This expansion improves readability of the callers.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:50 +09:00
Ryusuke Konishi 1376e931b7 nilfs2: eliminate nilfs_btnode_get function
This removes the obsolete nilfs_btnode_get() function and makes
nilfs_btree_get_block() directly call nilfs_btnode_submit_block().

This expansion will provide better opportunity for code optimization.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:50 +09:00
Ryusuke Konishi 75f65edfcc nilfs2: remove newblk argument from nilfs_btnode_submit_block
This removes the obsolete argument from nilfs_btnode_submit_block().
This will complete separating a create function of btree node.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:50 +09:00
Ryusuke Konishi 45f4910bc0 nilfs2: use nilfs_btnode_create_block function
This displaces nilfs_btnode_get() use to create new btree node block
with nilfs_btnode_create_block.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:49 +09:00
Ryusuke Konishi d501d73689 nilfs2: separate function for creating new btree node block
Adds a separate routine for creating a btree node block.  This is a
preparation to reduce the depth of function calls during submitting
btree node buffer.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:49 +09:00
Ryusuke Konishi b34a65069c nilfs2: avoid readahead on metadata file for create mode
This turns off readhead action of metadata file if nilfs_mdt_get_block
function was called with a create flag.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:49 +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 aa474a2201 nilfs2: add local variable to cache the number of clean segments
This makes it possible for sufile to get the number of clean segments
faster.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:49 +09:00
Ryusuke Konishi 7b16c8a211 nilfs2: unfold nilfs_sufile_block_get_header function
This unfolds the nilfs_sufile_block_get_header() function for
simplicity.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:48 +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 3961f0e277 nilfs2: eliminate inlines to directly read/write inode of metadata files
Removes two inline functions: nilfs_mdt_read_inode_direct() and
nilfs_mdt_write_inode_direct().

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
Ryusuke Konishi 9cb4e0d2b9 nilfs2: move out mark_inode_dirty calls from bmap routines
Previously, nilfs_bmap_add_blocks() and nilfs_bmap_sub_blocks() called
mark_inode_dirty() after they changed the number of data blocks.

This moves these calls outside bmap outermost functions like
nilfs_bmap_insert() or nilfs_bmap_truncate().

This will mitigate overhead for truncate or delete operation since
they repeatedly remove set of blocks.  Nearly 10 percent improvement
was observed for removal of a large file:

 # dd if=/dev/zero of=/test/aaa bs=1M count=512
 # time rm /test/aaa

  real  2.968s -> 2.705s

Further optimization may be possible by eliminating these
mark_inode_dirty() uses though I avoid mixing separate changes here.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:47 +09:00
Ryusuke Konishi 09bf4aae0a nilfs2: stop marking metadata inode dirty within btree operations
Since metadata file routines mark the inode dirty after they
successfully changed bmap objects, nilfs_mdt_mark_dirty() calls in
nilfs_bmap_add_blocks() and nilfs_bmap_sub_blocks() are redundant.

This removes these overlapping calls from the bmap routines.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:47 +09:00
Ryusuke Konishi 30db4e6c3d nilfs2: remove buffer locking from btree code
lock_buffer() and unlock_buffer() uses in btree.c are eliminable
because btree functions gain buffer heads through nilfs_btnode_get(),
which never returns an on-the-fly buffer.

Although nilfs_clear_dirty_page() and nilfs_copy_back_pages() in
nilfs_commit_gcdat_inode() juggle btree node buffers of DAT, this is
safe because these operations are protected by a log writer lock or
the metadata file semaphore of DAT.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:47 +09:00
Ryusuke Konishi a49762fd11 nilfs2: remove buffer locking in nilfs_mark_inode_dirty
This lock is eliminable because inodes on the buffer can be updated
independently.  Although a log writer also fills in bmap data on the
on-disk inodes, this update is exclusively done by a log writer lock.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:47 +09:00
Jiro SEKIBA e2073e7857 nilfs2: cleanup unused match_bool function
match_bool function is not used anymore.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:47 +09:00
Jiro SEKIBA 91f1953bf3 nilfs2: Using nobarrier option instead of barrier=off
Since most of fs using nofoobar style option,
modified barrier=off option as nobarrier.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:47 +09:00
Jiro SEKIBA 6600b9dd8e nilfs2: move definition of struct nilfs_btree_node
This is a trivial patch to expose struct nilfs_fs_btree_node.
The struct should be exposed outside of kernel, for it is disk format.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:46 +09:00
Ryusuke Konishi 9b945d537d nilfs2: get rid of BUG_ON use in btree lookup routines
The current btree lookup routines make a kernel oops when detected
inconsistency in btree blocks.  These routines should instead return a
proper error code because the inconsistency usually comes from
corruption of on-disk metadata.

This fixes the issue by converting BUG_ON calls to proper error
handlings.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:46 +09:00
Jiro SEKIBA 18dafac1a4 nilfs2: deleted inconsistent comment in nilfs_load_inode_block()
The comment says, "Caller of this function MUST lock s_inode_lock",
however just above the comment, it locks s_inode_lock in the function.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-15 17:17:46 +09:00
Ryusuke Konishi c1ea985c71 nilfs2: fix lock order reversal in chcp operation
Will fix the following lock order reversal lockdep detected:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.32-rc6 #7
-------------------------------------------------------
chcp/30157 is trying to acquire lock:
 (&nilfs->ns_mount_mutex){+.+.+.}, at: [<fed7cfcc>] nilfs_cpfile_change_cpmode+0x46/0x752 [nilfs2]

but task is already holding lock:
 (&nilfs->ns_segctor_sem){++++.+}, at: [<fed7ca32>] nilfs_transaction_begin+0xba/0x110 [nilfs2]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&nilfs->ns_segctor_sem){++++.+}:
       [<c105799c>] __lock_acquire+0x109c/0x139d
       [<c1057d26>] lock_acquire+0x89/0xa0
       [<c14151e2>] down_read+0x31/0x45
       [<fed6d77b>] nilfs_attach_checkpoint+0x8f/0x16b [nilfs2]
       [<fed6e393>] nilfs_get_sb+0x3e7/0x653 [nilfs2]
       [<c10c0ccb>] vfs_kern_mount+0x8b/0x124
       [<c10c0db2>] do_kern_mount+0x37/0xc3
       [<c10d7517>] do_mount+0x64d/0x69d
       [<c10d75cd>] sys_mount+0x66/0x95
       [<c1002a14>] sysenter_do_call+0x12/0x32

-> #1 (&type->s_umount_key#31/1){+.+.+.}:
       [<c105799c>] __lock_acquire+0x109c/0x139d
       [<c1057d26>] lock_acquire+0x89/0xa0
       [<c104c0f3>] down_write_nested+0x34/0x52
       [<c10c08fe>] sget+0x22e/0x389
       [<fed6e133>] nilfs_get_sb+0x187/0x653 [nilfs2]
       [<c10c0ccb>] vfs_kern_mount+0x8b/0x124
       [<c10c0db2>] do_kern_mount+0x37/0xc3
       [<c10d7517>] do_mount+0x64d/0x69d
       [<c10d75cd>] sys_mount+0x66/0x95
       [<c1002a14>] sysenter_do_call+0x12/0x32

-> #0 (&nilfs->ns_mount_mutex){+.+.+.}:
       [<c1057727>] __lock_acquire+0xe27/0x139d
       [<c1057d26>] lock_acquire+0x89/0xa0
       [<c1414d63>] mutex_lock_nested+0x41/0x23e
       [<fed7cfcc>] nilfs_cpfile_change_cpmode+0x46/0x752 [nilfs2]
       [<fed801b2>] nilfs_ioctl+0x11a/0x7da [nilfs2]
       [<c10cca12>] vfs_ioctl+0x27/0x6e
       [<c10ccf93>] do_vfs_ioctl+0x491/0x4db
       [<c10cd022>] sys_ioctl+0x45/0x5f
       [<c1002a14>] sysenter_do_call+0x12/0x32

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-13 10:33:24 +09:00
Ryusuke Konishi c083234f15 nilfs2: fix missing cleanup of gc cache on error cases
This fixes an -rc1 regression brought by the commit:
1cf58fa840 ("nilfs2: shorten freeze
period due to GC in write operation v3").

Although the patch moved out a function call of
nilfs_ioctl_move_blocks() to nilfs_ioctl_clean_segments() from
nilfs_ioctl_prepare_clean_segments(), it didn't move corresponding
cleanup job needed for the error case.

This will move the missing cleanup job to the destination function.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: Jiro SEKIBA <jir@unicus.jp>
2009-11-08 19:04:25 +09:00
Ryusuke Konishi 5399dd1fc8 nilfs2: fix kernel oops in error case of nilfs_ioctl_move_blocks
This fixes a kernel oops reported by Markus Trippelsdorf in the email
titled "[NILFS users] kernel Oops while running nilfs_cleanerd".

The oops was caused by a bug of error path in
nilfs_ioctl_move_blocks() function, which was inlined in
nilfs_ioctl_clean_segments().

nilfs_ioctl_move_blocks checks duplication of blocks which will be
moved in garbage collection.  But, the check should have be done
within nilfs_ioctl_move_inode_block() to prevent list corruption among
buffers storing the target blocks.

To fix the kernel oops, this moves forward the duplication check
before the list insertion.

I also tested this for stable trees [2.6.30, 2.6.31].

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: stable <stable@kernel.org>
2009-11-08 19:01:35 +09:00
Ryusuke Konishi 05b4358ad5 nilfs2: add zero-fill for new btree node buffers
Adds missing initialization of newly allocated b-tree node buffers.
This avoids garbage data to be mixed in b-tree node blocks.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-03 12:32:03 +09:00
Ryusuke Konishi aeda7f6343 nilfs2: fix irregular checkpoint creation due to data flush
When nilfs flushes out dirty data to reduce memory pressure, creation
of checkpoints is wrongly postponed.  This bug causes irregular
checkpoint creation especially in small footprint systems.

To correct this issue, a timer for the checkpoint creation has to be
continued if a log writer does not create a checkpoint.

This will do the correction.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-03 12:32:03 +09:00
Ryusuke Konishi b1e19e5601 nilfs2: fix dirty page accounting leak causing hang at write
Bruno Prémont and Dunphy, Bill noticed me that NILFS will certainly
hang on ARM-based targets.

I found this was caused by an underflow of dirty pages counter.  A
b-tree cache routine was marking page dirty without adjusting page
account information.

This fixes the dirty page accounting leak and resolves the hang on
arm-based targets.

Reported-by: Bruno Prémont <bonbons@linux-vserver.org>
Reported-by: Dunphy, Bill <WDunphy@tandbergdata.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Bruno Prémont <bonbons@linux-vserver.org>
Cc: stable <stable@kernel.org>
2009-11-03 12:31:36 +09:00
Alexey Dobriyan 828c09509b const: constify remaining file_operations
[akpm@linux-foundation.org: fix KVM]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:11 -07:00
Ryusuke Konishi 3cc811bffd nilfs2: fix missing initialization of i_dir_start_lookup member
The i_dir_start_lookup field in nilfs_inode_info objects should be
cleared when the objects are allocated, but the the initialization was
missing in case of reading from disk.  This adds the initialization.

Since the variable just gives a start page on directory lookups, the
bug was nonfatal until now.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-29 20:32:13 +09:00
Ryusuke Konishi 1f28fcd925 nilfs2: fix missing zero-fill initialization of btree node cache
This will fix file system corruption which infrequently happens after
mount.  The problem was reported from users with the title "[NILFS
users] Fail to mount NILFS." (Message-ID:
<200908211918.34720.yuri@itinteg.net>), and so forth.  I've also
experienced the corruption multiple times on kernel 2.6.30 and 2.6.31.

The problem turned out to be caused due to discordance between
mapping->nrpages of a btree node cache and the actual number of pages
hung on the cache; if the mapping->nrpages becomes zero even as it has
pages, truncate_inode_pages() returns without doing anything.  Usually
this is harmless except it may cause page leak, but garbage collection
fairly infrequently sees a stale page remained in the btree node cache
of DAT (i.e. disk address translation file of nilfs), and induces the
corruption.

I identified a missing initialization in btree node caches was the
root cause.  This corrects the bug.

I've tested this for kernel 2.6.30 and 2.6.31.

Reported-by: Yuri Chislov <yuri@itinteg.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: stable <stable@kernel.org>
2009-09-29 20:12:56 +09:00
Alexey Dobriyan f0f37e2f77 const: mark struct vm_struct_operations
* mark struct vm_area_struct::vm_ops as const
* mark vm_ops in AGP code

But leave TTM code alone, something is fishy there with global vm_ops
being used.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-27 11:39:25 -07:00
Alexey Dobriyan 6e1d5dcc2b const: mark remaining inode_operations as const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Alexey Dobriyan 7f09410bbc const: mark remaining address_space_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Alexey Dobriyan ac4cfdd6d1 const: mark remaining export_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Alexey Dobriyan b87221de6a const: mark remaining super_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
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 41f4db0f48 fs/Kconfig: move nilfs2 outside misc filesystems
Some people asked me questions like the following:

On Wed, 15 Jul 2009 13:11:21 +0200, Leon Woestenberg wrote:
> just wondering, any reasons why NILFS2 is one of the miscellaneous
> filesystems and, for example, btrfs, is not in Kconfig?

Actually, nilfs is NOT a filesystem came from other operating systems,
but a filesystem created purely for Linux.  Nor is it a flash
filesystem but that for generic block devices.

So, this moves nilfs outside the misc category as I responded in LKML
"Re: Why does NILFS2 hide under Miscellaneous filesystems?"
(Message-Id: <20090716.002526.93465395.ryusuke@osrg.net>).

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:16 +09:00
Ryusuke Konishi 0f3fe33b39 nilfs2: convert nilfs_bmap_lookup to an inline function
The nilfs_bmap_lookup() is now a wrapper function of
nilfs_bmap_lookup_at_level().

This moves the nilfs_bmap_lookup() to a header file converting it to
an inline function and gives an opportunity for optimization.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:16 +09:00
Ryusuke Konishi 2e0c2c7392 nilfs2: allow btree code to directly call dat operations
The current btree code is written so that btree functions call dat
operations via wrapper functions in bmap.c when they allocate, free,
or modify virtual block addresses.

This abstraction requires additional function calls and causes
frequent call of nilfs_bmap_get_dat() function since it is used in the
every wrapper function.

This removes the wrapper functions and makes them available from
btree.c and direct.c, which will increase the opportunity of
compiler optimization.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:16 +09:00
Ryusuke Konishi bd8169efae nilfs2: add update functions of virtual block address to dat
This is a preparation for the successive cleanup ("nilfs2: allow btree
to directly call dat operations").

This adds functions bundling a few operations to change an entry of
virtual block address on the dat file.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:15 +09:00
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 3218929dbd nilfs2: stop zero-fill of btree path just before free it
The btree path object is cleared just before it is freed.

This will remove the code doing the unnecessary clear operation.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:15 +09:00
Ryusuke Konishi 6d28f7ea43 nilfs2: remove unused btree argument from btree functions
Even though many btree functions take a btree object as their first
argument, most of them are not used in their functions.

This sticky use of the btree argument is hurting code readability and
giving the possibility of inefficient code generation.

So, this removes the unnecessary btree arguments.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:15 +09:00
Ryusuke Konishi 9ead986373 nilfs2: remove nilfs_dat_abort_start and nilfs_dat_abort_free
These functions are not called from any functions.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:15 +09:00
Jiro SEKIBA 1cf58fa840 nilfs2: shorten freeze period due to GC in write operation v3
This is a re-revised patch to shorten freeze period.
This version include a fix of the bug Konishi-san mentioned last time.

When GC is runnning, GC moves live block to difference segments.
Copying live blocks into memory is done in a transaction,
however it is not necessarily to be in the transaction.
This patch will get the nilfs_ioctl_move_blocks() out from
transaction lock and put it before the transaction.

I ran sysbench fileio test against nilfs partition.
I copied some DVD/CD images and created snapshot to create live blocks
before starting the benchmark.

Followings are summary of rc8 and rc8 w/ the patch of per-request
statistics, which is min/max and avg.  I ran each test three times and
bellow is average of those numers.

According to this benchmark result, average time is slightly degrated.
However, worstcase (max) result is significantly improved.
This can address a few seconds write freeze.

- random write per-request performance of rc8
 min   0.843ms
 max 680.406ms
 avg   3.050ms
- random write per-request performance of rc8 w/ this patch
 min   0.843ms -> 100.00%
 max 380.490ms ->  55.90%
 avg   3.233ms -> 106.00%

- sequential write per-request performance of rc8
 min   0.736ms
 max 774.343ms
 avg   2.883ms
- sequential write per-request performance of rc8 w/ this patch
 min   0.720ms ->  97.80%
 max  644.280ms->  83.20%
 avg   3.130ms -> 108.50%

-----8<-----8<-----nilfs_cleanerd.conf-----8<-----8<-----
protection_period       150
selection_policy        timestamp       # timestamp in ascend order
nsegments_per_clean     2
cleaning_interval       2
retry_interval          60
use_mmap
log_priority            info
-----8<-----8<-----nilfs_cleanerd.conf-----8<-----8<-----

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:15 +09:00
Zhu Yanhai 43be0ec038 nilfs2: add more check routines in mount process
nilfs2: Add more safeguard routines and protections in mount process,
which also makes nilfs2 report consistency error messages when
checkpoint number is invalid.

Signed-off-by: Zhu Yanhai <zhu.yanhai@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:14 +09:00
Zhang Qiang a4f0b9c5b4 nilfs2: An unassigned variable is assigned to a never used structure member
nilfs2: In procedure 'nilfs_get_sb()', when a nilfs filesysttem is
mounted for the first time, local variable 'nilfs->ns_last_cno' is
used before loading the latest checkpoint number from disk (in
'nilfs_fill_super'). 'nilfs->ns_last_cno' is assigned to 'sd.cno', but
'sd.cno' has never been used in the procedure.

Signed-off-by: Zhang Qiang <zhangqiang.buaa@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:14 +09:00
Ryusuke Konishi c1b353f04a nilfs2: use GFP_NOIO for bio_alloc instead of GFP_NOWAIT
Alberto Bertogli advised me about bio_alloc() use in nilfs:
On Sat, 13 Jun 2009 22:52:40 -0300, Alberto Bertogli wrote:
> By the way, those bio_alloc()s are using GFP_NOWAIT but it looks
> like they could use at least GFP_NOIO or GFP_NOFS, since the caller
> can (and sometimes do) sleep. The only caller is nilfs_submit_bh(),
> which calls nilfs_submit_seg_bio() which can sleep calling
> wait_for_completion().

This takes in the comment and replaces the use of GFP_NOWAIT flag with
GFP_NOIO.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:14 +09:00
Jiro SEKIBA 1dfa27105a nilfs2: stop using periodic write_super callback
This removes nilfs_write_super and commit super block in nilfs
internal thread, instead of periodic write_super callback.

VFS layer calls ->write_super callback periodically.  However,
it looks like that calling back is ommited when disk I/O is busy.
And when cleanerd (nilfs GC) is runnig, disk I/O tend to be busy thus
nilfs superblock is not synchronized as nilfs designed.

To avoid it, syncing superblock by nilfs thread instead of pdflush.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:14 +09:00
Jiro SEKIBA 79efdd9411 nilfs2: clean up nilfs_write_super
Separate conditions that check if syncing super block and alternative
super block are required as inline functions to reuse the conditions.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:14 +09:00
Jiro SEKIBA 6233caa9d5 nilfs2: fix disorder of nilfs_write_super in nilfs_sync_fs
This fixes disorder of nilfs_write_super in nilfs_sync_fs.  Commiting
super block must be the end of the function so that every changes are
reflected.

->sync_fs() is not called frequently so this makes nilfs_sync_fs call
nilfs_commit_super instead of nilfs_write_super.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:14 +09:00
Jiro SEKIBA ec5d66abdb nilfs2: remove redundant super block commit
This removes redundant super block commit.

nilfs_write_super will call nilfs_commit_super to store super block
into block device.  However, nilfs_put_super will call
nilfs_commit_super right after calling nilfs_write_super.  So calling
nilfs_write_super in nilfs_put_super would be redundant.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:13 +09:00
Jiro SEKIBA b58a285ba4 nilfs2: implement nilfs_show_options to display mount options in /proc/mounts
This is a patch to display mount options in procfs.
Mount options will show up in the /proc/mounts as other fs does.

...
/dev/sda6 /mnt nilfs2 ro,relatime,barrier=off,cp=3,order=strict 0 0
...

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:13 +09:00
Ryusuke Konishi 1435110467 nilfs2: always lookup disk block address before reading metadata block
The current metadata file code skips disk address lookup for its data
block if the buffer has a mapped flag.

This has a potential risk to cause read request to be performed
against the stale block address that GC moved, and it may lead to meta
data corruption.  The mapped flag is safe if the buffer has an
uptodate flag, otherwise it may prevent necessary update of disk
address in the next read.

This will avoid the potential problem by ensuring disk address lookup
before reading metadata block even for buffers with the mapped flag.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:13 +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 #51
 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
Heiko Carstens b5696e5e0d nilfs2: fix format string compile warning (ino_t)
Unlike on most other architectures ino_t is an unsigned int on s390.
So add an explicit cast to avoid this compile warning:

fs/nilfs2/recovery.c: In function 'recover_dsync_blocks':
fs/nilfs2/recovery.c:555: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:13 +09:00
Ryusuke Konishi 1b2f5a641b nilfs2: fix ignored error code in __nilfs_read_inode()
The __nilfs_read_inode function is ignoring the error code returned
from nilfs_read_inode_common(), and wrongly delivers a success code
(zero) when it escapes from the function in erroneous cases.

This adds the missing error handling.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-14 18:27:12 +09:00
Ryusuke Konishi b1f1b8ce0a nilfs2: fix preempt count underflow in nilfs_btnode_prepare_change_key
This will fix the following preempt count underflow reported from
users with the title "[NILFS users] segctord problem" (Message-ID:
<949415.6494.qm@web58808.mail.re1.yahoo.com> and Message-ID:
<debc30fc0908270825v747c1734xa59126623cfd5b05@mail.gmail.com>):

 WARNING: at kernel/sched.c:4890 sub_preempt_count+0x95/0xa0()
 Hardware name: HP Compaq 6530b (KR980UT#ABC)
 Modules linked in: bridge stp llc bnep rfcomm l2cap xfs exportfs nilfs2 cowloop loop vboxnetadp vboxnetflt vboxdrv btusb bluetooth uvcvideo videodev v4l1_compat v4l2_compat_ioctl32 arc4 snd_hda_codec_analog ecb iwlagn iwlcore rfkill lib80211 mac80211 snd_hda_intel snd_hda_codec ehci_hcd uhci_hcd usbcore snd_hwdep snd_pcm tg3 cfg80211 psmouse snd_timer joydev libphy ohci1394 snd_page_alloc hp_accel lis3lv02d ieee1394 led_class i915 drm i2c_algo_bit video backlight output i2c_core dm_crypt dm_mod
 Pid: 4197, comm: segctord Not tainted 2.6.30-gentoo-r4-64 #7
 Call Trace:
  [<ffffffff8023fa05>] ? sub_preempt_count+0x95/0xa0
  [<ffffffff802470f8>] warn_slowpath_common+0x78/0xd0
  [<ffffffff8024715f>] warn_slowpath_null+0xf/0x20
  [<ffffffff8023fa05>] sub_preempt_count+0x95/0xa0
  [<ffffffffa04ce4db>] nilfs_btnode_prepare_change_key+0x11b/0x190 [nilfs2]
  [<ffffffffa04d01ad>] nilfs_btree_assign_p+0x19d/0x1e0 [nilfs2]
  [<ffffffffa04d10ad>] nilfs_btree_assign+0xbd/0x130 [nilfs2]
  [<ffffffffa04cead7>] nilfs_bmap_assign+0x47/0x70 [nilfs2]
  [<ffffffffa04d9bc6>] nilfs_segctor_do_construct+0x956/0x20f0 [nilfs2]
  [<ffffffff805ac8e2>] ? _spin_unlock_irqrestore+0x12/0x40
  [<ffffffff803c06e0>] ? __up_write+0xe0/0x150
  [<ffffffff80262959>] ? up_write+0x9/0x10
  [<ffffffffa04ce9f3>] ? nilfs_bmap_test_and_clear_dirty+0x43/0x60 [nilfs2]
  [<ffffffffa04cd627>] ? nilfs_mdt_fetch_dirty+0x27/0x60 [nilfs2]
  [<ffffffffa04db5fc>] nilfs_segctor_construct+0x8c/0xd0 [nilfs2]
  [<ffffffffa04dc3dc>] nilfs_segctor_thread+0x15c/0x3a0 [nilfs2]
  [<ffffffffa04dbe20>] ? nilfs_construction_timeout+0x0/0x10 [nilfs2]
  [<ffffffff80252633>] ? add_timer+0x13/0x20
  [<ffffffff802370da>] ? __wake_up_common+0x5a/0x90
  [<ffffffff8025e960>] ? autoremove_wake_function+0x0/0x40
  [<ffffffffa04dc280>] ? nilfs_segctor_thread+0x0/0x3a0 [nilfs2]
  [<ffffffffa04dc280>] ? nilfs_segctor_thread+0x0/0x3a0 [nilfs2]
  [<ffffffff8025e556>] kthread+0x56/0x90
  [<ffffffff8020cdea>] child_rip+0xa/0x20
  [<ffffffff8025e500>] ? kthread+0x0/0x90
  [<ffffffff8020cde0>] ? child_rip+0x0/0x20

This problem was caused due to a missing radix_tree_preload() call in
the retry path of nilfs_btnode_prepare_change_key() function.

Reported-by: Eric A <eric225125@yahoo.com>
Reported-by: Jerome Poulin <jeromepoulin@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Jerome Poulin <jeromepoulin@gmail.com>
Cc: stable@kernel.org
2009-08-31 12:03:06 +09:00
Ryusuke Konishi a924586036 nilfs2: fix oopses with doubly mounted snapshots
will fix kernel oopses like the following:

 # mount -t nilfs2 -r -o cp=20 /dev/sdb1 /test1
 # mount -t nilfs2 -r -o cp=20 /dev/sdb1 /test2
 # umount /test1
 # umount /test2

BUG: sleeping function called from invalid context at arch/x86/mm/fault.c:1069
in_atomic(): 0, irqs_disabled(): 1, pid: 3886, name: umount.nilfs2
1 lock held by umount.nilfs2/3886:
 #0:  (&type->s_umount_key#31){+.+...}, at: [<c10b398a>] deactivate_super+0x52/0x6c
irq event stamp: 1219
hardirqs last  enabled at (1219): [<c135c774>] __mutex_unlock_slowpath+0xf8/0x119
hardirqs last disabled at (1218): [<c135c6d5>] __mutex_unlock_slowpath+0x59/0x119
softirqs last  enabled at (1214): [<c1033316>] __do_softirq+0x1a5/0x1ad
softirqs last disabled at (1205): [<c1033354>] do_softirq+0x36/0x5a
Pid: 3886, comm: umount.nilfs2 Not tainted 2.6.31-rc6 #55
Call Trace:
 [<c1023549>] __might_sleep+0x107/0x10e
 [<c13603c0>] do_page_fault+0x246/0x397
 [<c136017a>] ? do_page_fault+0x0/0x397
 [<c135e753>] error_code+0x6b/0x70
 [<c136017a>] ? do_page_fault+0x0/0x397
 [<c104f805>] ? __lock_acquire+0x91/0x12fd
 [<c1050a62>] ? __lock_acquire+0x12ee/0x12fd
 [<c1050a62>] ? __lock_acquire+0x12ee/0x12fd
 [<c1050b2b>] lock_acquire+0xba/0xdd
 [<d0d17d3f>] ? nilfs_detach_segment_constructor+0x2f/0x2fa [nilfs2]
 [<c135d4fe>] down_write+0x2a/0x46
 [<d0d17d3f>] ? nilfs_detach_segment_constructor+0x2f/0x2fa [nilfs2]
 [<d0d17d3f>] nilfs_detach_segment_constructor+0x2f/0x2fa [nilfs2]
 [<c104ea2c>] ? mark_held_locks+0x43/0x5b
 [<c104ecb1>] ? trace_hardirqs_on_caller+0x10b/0x133
 [<c104ece4>] ? trace_hardirqs_on+0xb/0xd
 [<d0d09ac1>] nilfs_put_super+0x2f/0xca [nilfs2]
 [<c10b3352>] generic_shutdown_super+0x49/0xb8
 [<c10b33de>] kill_block_super+0x1d/0x31
 [<c10e6599>] ? vfs_quota_off+0x0/0x12
 [<c10b398f>] deactivate_super+0x57/0x6c
 [<c10c4bc3>] mntput_no_expire+0x8c/0xb4
 [<c10c5094>] sys_umount+0x27f/0x2a4
 [<c10c50c6>] sys_oldumount+0xd/0xf
 [<c10031a4>] sysenter_do_call+0x12/0x38
 ...

This turns out to be a bug brought by an -rc1 patch ("nilfs2: simplify
remaining sget() use").

In the patch, a new "put resource" function, nilfs_put_sbinfo()
was introduced to delay freeing nilfs_sb_info struct.

But the nilfs_put_sbinfo() mistakenly used atomic_dec_and_test()
function to check the reference count, and it caused the nilfs_sb_info
was freed when user mounted a snapshot twice.

This bug also suggests there was unseen memory leak in usual mount
/umount operations for nilfs.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-19 02:10:13 +09:00
Zhang Qiang 1154ecbd2f nilfs2: missing a read lock for segment writer in nilfs_attach_checkpoint()
'ns_cno' of structure 'the_nilfs' must be protected from segment
writer, in other words, the caller of nilfs_get_checkpoint should hold
read lock for nilfs->ns_segctor_sem.  This patch adds the lock/unlock
operations in nilfs_attach_checkpoint() when calling
nilfs_cpfile_get_checkpoint().

Signed-off-by: Zhang Qiang <zhangqiang.buaa@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-18 17:32:27 +09:00
Ryusuke Konishi 01a261e09a nilfs2: fix missing unlock in error path of nilfs_mdt_write_page
This adds a missing unlock of nilfs->ns_writer_mutex in
nilfs_mdt_write_page() function.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-02 22:24:15 +09:00
Ryusuke Konishi a97778457f nilfs2: fix oops due to inconsistent state in page with discrete b-tree nodes
Andrea Gelmini gave me a report that a kernel oops hit on a nilfs
filesystem with a 1KB block size when doing rsync.

This turned out to be caused by an inconsistency of dirty state
between a page and its buffers storing b-tree node blocks.

If the page had multiple buffers split over multiple logs, and if the
logs were written at a time, a dirty flag remained in the page even
every dirty flag in the buffers was cleared.

This will fix the failure by dropping the dirty flag properly for
pages with the discrete multiple b-tree nodes.

Reported-by: Andrea Gelmini <andrea.gelmini@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Andrea Gelmini <andrea.gelmini@gmail.com>
Cc: stable@kernel.org
2009-08-01 22:48:32 +09:00
Ryusuke Konishi 4fed598a49 fs/Kconfig: move nilfs2 out
fs/Kconfig file was split into individual fs/*/Kconfig files before
nilfs was merged.  I've found the current config entry of nilfs is
tainting the work.  Sorry, I didn't notice.  This fixes the violation.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
2009-07-14 12:34:17 +09:00
Alexey Dobriyan 405f55712d headers: smp_lock.h redux
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:22:34 -07:00
Jiro SEKIBA d9a0a345ab nilfs2: fix disorder in cp count on error during deleting checkpoints
This fixes a bug that checkpoint count gets wrong on errors when
deleting a series of checkpoints.

The count error is persistent since the checkpoint count is stored on
disk.  Some userland programs refer to the count via ioctl, and this
bugfix is needed to prevent malfunction of such programs.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: stable@kernel.org
2009-07-05 10:44:20 +09:00
Ryusuke Konishi ff54de363a nilfs2: fix lockdep warning between regular file and inode file
This will fix the following false positive of recursive locking which
lockdep has detected:

=============================================
[ INFO: possible recursive locking detected ]
2.6.30-nilfs #42
---------------------------------------------
nilfs_cleanerd/10607 is trying to acquire lock:
 (&bmap->b_sem){++++-.}, at: [<e0d025b7>] nilfs_bmap_lookup_at_level+0x1a/0x74 [nilfs2]

but task is already holding lock:
 (&bmap->b_sem){++++-.}, at: [<e0d024e0>] nilfs_bmap_truncate+0x19/0x6a [nilfs2]
other info that might help us debug this:
2 locks held by nilfs_cleanerd/10607:
 #0:  (&nilfs->ns_segctor_sem){++++.+}, at: [<e0d0d75a>] nilfs_transaction_begin+0xb6/0x10c [nilfs2]
 #1:  (&bmap->b_sem){++++-.}, at: [<e0d024e0>] nilfs_bmap_truncate+0x19/0x6a [nilfs2]

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-07-05 10:44:20 +09:00
Ryusuke Konishi 4a52df7797 nilfs2: fix incorrect KERN_CRIT messages in case of write failures
In case of write-failure retries, the following KERN_CRIT level
messages are mistakenly output by nilfs_dat_commit_start() function:

nilfs_dat_commit_start: vbn = 408463, start = 12506, end = 18446744073709551615, pbn = 530210
nilfs_dat_commit_start: vbn = 408515, start = 12506, end = 18446744073709551615, pbn = 530211
nilfs_dat_commit_start: vbn = 408464, start = 12506, end = 18446744073709551615, pbn = 530212
...

This suppresses these messages.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: stable@kernel.org
2009-07-05 10:44:20 +09:00
Ryusuke Konishi 8227b29722 nilfs2: fix hang problem of log writer which occurs after write failures
Leandro Lucarella gave me a report that nilfs gets stuck after its
write function fails.

The problem turned out to be caused by bugs which leave writeback flag
on pages.  This fixes the problem by ensuring to clear the writeback
flag in error path.

Reported-by: Leandro Lucarella <llucax@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: stable@kernel.org
2009-07-05 10:44:20 +09:00
Ryusuke Konishi 0cfae3d879 nilfs2: remove unlikely directive causing mis-conversion of error code
The following error code handling in nilfs_segctor_write() function
wrongly converted negative error codes to a truth value (i.e. 1):

   err = unlikely(err) ? : res;

which originaly meant to be

   err = err ? : res;

This mis-conversion caused that write or sync functions receive the
unexpected error code.  This fixes the bug by removing the unlikely
directive.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: stable@kernel.org
2009-07-05 10:44:19 +09:00
Al Viro d441b1c293 switch nilfs2 to inode->i_acl
Actually, get rid of private analog, since nothing in there is
using ACLs at all so far.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-24 08:17:05 -04:00
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 3f82ff5516 nilfs2: get rid of sget use for checking if current mount is present
This stops using sget() for checking if an r/w-mount or an r/o-mount
exists on the device.  This elimination uses a back pointer to the
current mount added to nilfs object.

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 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 81fc20bd0e nilfs2: remove meaningless EBUSY case from nilfs_get_sb function
The following EBUSY case in nilfs_get_sb() is meaningless.  Indeed,
this error code is never returned to the caller.

    if (!s->s_root) {
          ...
    } else if (!(s->s_flags & MS_RDONLY)) {
        err = -EBUSY;
    }

This simply removes the else case.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:17 -04:00
Christoph Hellwig d731e06323 nilfs2: call nilfs2_write_super from nilfs2_sync_fs
The call to ->write_super from __sync_filesystem will go away, so make
sure nilfs2 performs the same actions from inside ->sync_fs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:17 -04:00
Alessio Igor Bogani 337eb00a2c Push BKL down into ->remount_fs()
[xfs, btrfs, capifs, shmem don't need BKL, exempt]

Signed-off-by: Alessio Igor Bogani <abogani@texware.it>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:11 -04:00
Christoph Hellwig 6cfd014842 push BKL down into ->put_super
Move BKL into ->put_super from the only caller.  A couple of
filesystems had trivial enough ->put_super (only kfree and NULLing of
s_fs_info + stuff in there) to not get any locking: coda, cramfs, efs,
hugetlbfs, omfs, qnx4, shmem, all others got the full treatment.  Most
of them probably don't need it, but I'd rather sort that out individually.
Preferably after all the other BKL pushdowns in that area.

[AV: original used to move lock_super() down as well; these changes are
removed since we don't do lock_super() at all in generic_shutdown_super()
now]
[AV: fuse, btrfs and xfs are known to need no damn BKL, exempt]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:07 -04:00
Christoph Hellwig 8c85e12512 remove ->write_super call in generic_shutdown_super
We just did a full fs writeout using sync_filesystem before, and if
that's not enough for the filesystem it can perform it's own writeout
in ->put_super, which many filesystems already do.

Move a call to foofs_write_super into every foofs_put_super for now to
guarantee identical behaviour until it's cleaned up by the individual
filesystem maintainers.

Exceptions:

 - affs already has identical copy & pasted code at the beginning of
   affs_put_super so no need to do it twice.
 - xfs does the right thing without it and I have changes pending for
   the xfs tree touching this are so I don't really need conflicts
   here..

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:06 -04:00
Linus Torvalds c9059598ea Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block: (153 commits)
  block: add request clone interface (v2)
  floppy: fix hibernation
  ramdisk: remove long-deprecated "ramdisk=" boot-time parameter
  fs/bio.c: add missing __user annotation
  block: prevent possible io_context->refcount overflow
  Add serial number support for virtio_blk, V4a
  block: Add missing bounce_pfn stacking and fix comments
  Revert "block: Fix bounce limit setting in DM"
  cciss: decode unit attention in SCSI error handling code
  cciss: Remove no longer needed sendcmd reject processing code
  cciss: change SCSI error handling routines to work with interrupts enabled.
  cciss: separate error processing and command retrying code in sendcmd_withirq_core()
  cciss: factor out fix target status processing code from sendcmd functions
  cciss: simplify interface of sendcmd() and sendcmd_withirq()
  cciss: factor out core of sendcmd_withirq() for use by SCSI error handling code
  cciss: Use schedule_timeout_uninterruptible in SCSI error handling code
  block: needs to set the residual length of a bidi request
  Revert "block: implement blkdev_readpages"
  block: Fix bounce limit setting in DM
  Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt
  ...

Manually fix conflicts with tracing updates in:
	block/blk-sysfs.c
	drivers/ide/ide-atapi.c
	drivers/ide/ide-cd.c
	drivers/ide/ide-floppy.c
	drivers/ide/ide-tape.c
	include/trace/events/block.h
	kernel/trace/blktrace.c
2009-06-11 11:10:35 -07:00
Ryusuke Konishi c3a7abf06c nilfs2: support contiguous lookup of blocks
Although get_block() callback function can return extent of contiguous
blocks with bh->b_size, nilfs_get_block() function did not support
this feature.

This adds contiguous lookup feature to the block mapping codes of
nilfs, and allows the nilfs_get_blocks() function to return the extent
information by applying the feature.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:12 +09:00
Ryusuke Konishi fa032744ad nilfs2: add sync_page method to page caches of meta data
This applies block_sync_page() function to the sync_page method of
page caches for meta data files, gc page caches, and btree node
buffers.  This is a companion patch of ("nilfs2: enable sync_page
mothod") which applied the function for data pages.

This allows lock_page() for those meta data to unplug pending bio
requests.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:12 +09:00
Ryusuke Konishi a53b4751ae nilfs2: use device's backing_dev_info for btree node caches
Previously, default_backing_dev_info was used for the mapping of btree
node caches.  This uses device dependent backing_dev_info to allow
detailed control of the device for the btree node pages.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:12 +09:00
Ryusuke Konishi 30c25be71f nilfs2: return EBUSY against delete request on snapshot
This helps userland programs like the rmcp command to distinguish
error codes returned against a checkpoint removal request.

Previously -EPERM was returned, and not discriminable from real
permission errors.  This also allows removal of the latest checkpoint
because the deletion leads to create a new checkpoint, and thus it's
harmless for the filesystem.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:12 +09:00
Ryusuke Konishi e85dc1d529 nilfs2: enable sync_page method
This adds a missing sync_page method which unplugs bio requests when
waiting for page locks. This will improve read performance of nilfs.

Here is a measurement result using dd command.

Without this patch:

 # mount -t nilfs2 /dev/sde1 /test
 # dd if=/test/aaa of=/dev/null bs=512k
 1024+0 records in
 1024+0 records out
 536870912 bytes (537 MB) copied, 6.00688 seconds, 89.4 MB/s

With this patch:

 # mount -t nilfs2 /dev/sde1 /test
 # dd if=/test/aaa of=/dev/null bs=512k
 1024+0 records in
 1024+0 records out
 536870912 bytes (537 MB) copied, 3.54998 seconds, 151 MB/s

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:11 +09:00
Ryusuke Konishi 30bda0b8ae nilfs2: set bio unplug flag for the last bio in segment
This sets BIO_RW_UNPLUG flag on the last bio of each segment during
write.  The last bio should be unplugged immediately because the
caller waits for the completion after the submission.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:11 +09:00
Ryusuke Konishi 003ff182fd nilfs2: allow future expansion of metadata read out via get info ioctl
Nilfs has some ioctl commands to read out metadata from meta data
files:

 - NILFS_IOCTL_GET_CPINFO for checkpoint file,
 - NILFS_IOCTL_GET_SUINFO for segment usage file, and
 - NILFS_IOCTL_GET_VINFO for Disk Address Transalation (DAT) file,
   respectively.

Every routine on these metadata files is implemented so that it allows
future expansion of on-disk format.  But, the above ioctl commands do
not support expansion even though nilfs_argv structure can handle
arbitrary size for data exchanged via ioctl.

This allows future expansion of the following structures which give
basic format of the "get information" ioctls:

 - struct nilfs_cpinfo
 - struct nilfs_suinfo
 - struct nilfs_vinfo

So, this introduces forward compatility of such ioctl commands.

In this patch, a sanity check in nilfs_ioctl_get_info() function is
changed to accept larger data structure [1], and metadata read
routines are rewritten so that they become compatible for larger
structures; the routines will just ignore the remaining fields which
the current version of nilfs doesn't know.

[1] The ioctl function already has another upper limit (PAGE_SIZE
    against a structure, which appears in nilfs_ioctl_wrap_copy
    function), and this will not cause security problem.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:11 +09:00
Hisashi Hifumi 258ef67e24 NILFS2: Pagecache usage optimization on NILFS2
Hi,

I introduced "is_partially_uptodate" aops for NILFS2.

A page can have multiple buffers and even if a page is not uptodate, some buffers
can be uptodate on pagesize != blocksize environment.
This aops checks that all buffers which correspond to a part of a file
that we want to read are uptodate. If so, we do not have to issue actual
read IO to HDD even if a page is not uptodate because the portion we
want to read are uptodate.
"block_is_partially_uptodate" function is already used by ext2/3/4.
With the following patch random read/write mixed workloads or random read after
random write workloads can be optimized and we can get performance improvement.

I did a performance test using the sysbench.

1 --file-block-size=8K --file-total-size=2G --file-test-mode=rndrw --file-fsync-freq=0 --fil
e-rw-ratio=1 run

-2.6.30-rc5

Test execution summary:
    total time:                          151.2907s
    total number of events:              200000
    total time taken by event execution: 2409.8387
    per-request statistics:
         min:                            0.0000s
         avg:                            0.0120s
         max:                            0.9306s
         approx.  95 percentile:         0.0439s

Threads fairness:
    events (avg/stddev):           12500.0000/238.52
    execution time (avg/stddev):   150.6149/0.01

-2.6.30-rc5-patched

Test execution summary:
    total time:                          140.8828s
    total number of events:              200000
    total time taken by event execution: 2240.8577
    per-request statistics:
         min:                            0.0000s
         avg:                            0.0112s
         max:                            0.8750s
         approx.  95 percentile:         0.0418s

Threads fairness:
    events (avg/stddev):           12500.0000/218.43
    execution time (avg/stddev):   140.0536/0.01

arch: ia64
pagesize: 16k

Thanks.

Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:11 +09:00
Ryusuke Konishi 7cde31d7d6 nilfs2: remove nilfs_btree_operations from btree mapping
will remove indirect function calls using nilfs_btree_operations
table.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:11 +09:00
Ryusuke Konishi 355c6b6103 nilfs2: remove nilfs_direct_operations from direct mapping
will remove indirect function calls using nilfs_direct_operations
table.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:11 +09:00
Ryusuke Konishi d4b961576d nilfs2: remove bmap pointer operations
Previously, the bmap codes of nilfs used three types of function
tables.  The abuse of indirect function calls decreased source
readability and suffered many indirect jumps which would confuse
branch prediction of processors.

This eliminates one type of the function tables,
nilfs_bmap_ptr_operations, which was used to dispatch low level
pointer operations of the nilfs bmap.

This adds a new integer variable "b_ptr_type" to nilfs_bmap struct,
and uses the value to select the pointer operations.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:10 +09:00
Ryusuke Konishi 3033342a0b nilfs2: remove useless b_low and b_high fields from nilfs_bmap struct
This will cut off 16 bytes from the nilfs_bmap struct which is
embedded in the on-memory inode of nilfs.

The b_high field was never used, and the b_low field stores a constant
value which can be determined by whether the inode uses btree for
block mapping or not.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:10 +09:00
Ryusuke Konishi e473c1f265 nilfs2: remove pointless NULL check of bpop_commit_alloc_ptr function
This indirect function is set to NULL only for gc cache inodes, but
the gc cache inodes never call this function.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:10 +09:00
Ryusuke Konishi f198dbb9cf nilfs2: move get block functions in bmap.c into btree codes
Two get block function for btree nodes, nilfs_bmap_get_block() and
nilfs_bmap_get_new_block(), are called only from the btree codes.
This relocation will increase opportunities of compiler optimization.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:10 +09:00
Ryusuke Konishi 9f098900ad nilfs2: remove nilfs_bmap_delete_block
nilfs_bmap_delete_block() is a wrapper function calling
nilfs_btnode_delete().  This removes it for simplicity.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:10 +09:00
Ryusuke Konishi 087d01b425 nilfs2: remove nilfs_bmap_put_block
nilfs_bmap_put_block() is a wrapper function calling brelse().  This
eliminates the wrapper for simplicity.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:10 +09:00
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
Ryusuke Konishi 071cb4b819 nilfs2: eliminate removal list of segments
This will clean up the removal list of segments and the related
functions from segment.c and ioctl.c, which have hurt code
readability.

This elimination is applied by using nilfs_sufile_updatev() previously
introduced in the patch ("nilfs2: add sufile function that can modify
multiple segment usages").

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:09 +09:00
Ryusuke Konishi dda54f4b87 nilfs2: add sufile function that can modify multiple segment usages
This is a preparation for the later cleanup patch ("nilfs2: remove
list of freeing segments").

This adds nilfs_sufile_updatev() to sufile, which can modify multiple
segment usages at a time.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:09 +09:00
Ryusuke Konishi d97a51a7e3 nilfs2: unify bmap operations starting use of indirect block address
This simplifies some low level functions of bmap.

Three bmap pointer operations, nilfs_bmap_start_v(),
nilfs_bmap_commit_v(), and nilfs_bmap_abort_v(), are unified into one
nilfs_bmap_start_v() function. And the related indirect function calls
are replaced with it.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:09 +09:00
Ryusuke Konishi 6582207064 nilfs2: remove nilfs_dat_prepare_free function
This function is unused.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:09 +09:00
Ryusuke Konishi 62013ab5d5 nilfs2: fix bh leak in nilfs_cpfile_delete_checkpoints function
The nilfs_cpfile_delete_checkpoints() wrongly skips brelse() for the
header block of checkpoint file in case of errors.  This fixes the
leak bug.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-05-30 22:07:50 +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 d504685363 nilfs2: fix memory leak in nilfs_ioctl_clean_segments
This fixes a new memory leak problem in garbage collection.  The
problem was brought by the bugfix patch ("nilfs2: fix lock order
reversal in nilfs_clean_segments ioctl").

Thanks to Kentaro Suzuki for finding this problem.

Reported-by: Kentaro Suzuki <k_suzuki@ms.sylc.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-05-22 20:49:04 +09:00
Ryusuke Konishi 83aca8f480 nilfs2: check size of array structured data exchanged via ioctls
Although some ioctls of nilfs2 exchange data in the form of indirectly
referenced array, some of them lack size check on the array elements.

This inserts the missing checks and rejects requests if data of ioctl
does not have a valid format.

We usually don't have to check size of structures that we associated
with ioctl commands because the size is tested implicitly for
identifying ioctl command; the checks this patch adds are for the
cases where the implicit check is not applied.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-05-12 01:48:54 +09:00
Ryusuke Konishi 4f6b828837 nilfs2: fix lock order reversal in nilfs_clean_segments ioctl
This is a companion patch to ("nilfs2: fix possible circular locking
for get information ioctls").

This corrects lock order reversal between mm->mmap_sem and
nilfs->ns_segctor_sem in nilfs_clean_segments() which was detected by
lockdep check:

 =======================================================
 [ INFO: possible circular locking dependency detected ]
 2.6.30-rc3-nilfs-00003-g360bdc1 #7
 -------------------------------------------------------
 mmap/5294 is trying to acquire lock:
  (&nilfs->ns_segctor_sem){++++.+}, at: [<d0d0e846>] nilfs_transaction_begin+0xb6/0x10c [nilfs2]

 but task is already holding lock:
  (&mm->mmap_sem){++++++}, at: [<c043700a>] do_page_fault+0x1d8/0x30a

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (&mm->mmap_sem){++++++}:
        [<c01470a5>] __lock_acquire+0x1066/0x13b0
        [<c01474a9>] lock_acquire+0xba/0xdd
        [<c01836bc>] might_fault+0x68/0x88
        [<c023c61d>] copy_from_user+0x2a/0x111
        [<d0d120d0>] nilfs_ioctl_prepare_clean_segments+0x1d/0xf1 [nilfs2]
        [<d0d0e2aa>] nilfs_clean_segments+0x6d/0x1b9 [nilfs2]
        [<d0d11f68>] nilfs_ioctl+0x2ad/0x318 [nilfs2]
        [<c01a3be7>] vfs_ioctl+0x22/0x69
        [<c01a408e>] do_vfs_ioctl+0x460/0x499
        [<c01a4107>] sys_ioctl+0x40/0x5a
        [<c01031a4>] sysenter_do_call+0x12/0x38
        [<ffffffff>] 0xffffffff

 -> #0 (&nilfs->ns_segctor_sem){++++.+}:
        [<c0146e0b>] __lock_acquire+0xdcc/0x13b0
        [<c01474a9>] lock_acquire+0xba/0xdd
        [<c0433f1d>] down_read+0x2a/0x3e
        [<d0d0e846>] nilfs_transaction_begin+0xb6/0x10c [nilfs2]
        [<d0cfe0e5>] nilfs_page_mkwrite+0xe7/0x154 [nilfs2]
        [<c0183b0b>] __do_fault+0x165/0x376
        [<c01855cd>] handle_mm_fault+0x287/0x5d1
        [<c043712d>] do_page_fault+0x2fb/0x30a
        [<c0435462>] error_code+0x72/0x78
        [<ffffffff>] 0xffffffff

where nilfs_clean_segments() holds:

  nilfs->ns_segctor_sem -> copy_from_user()
                             --> page fault -> mm->mmap_sem

And, page fault path may hold:

  page fault -> mm->mmap_sem
         --> nilfs_page_mkwrite() -> nilfs->ns_segctor_sem

Even though nilfs_clean_segments() does not perform write access on
given user pages, it may cause deadlock because nilfs->ns_segctor_sem
is shared per device and mm->mmap_sem can be shared with other tasks.

To avoid this problem, this patch moves all calls of copy_from_user()
outside the nilfs->ns_segctor_sem lock in the ioctl.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-05-11 14:54:41 +09:00
Ryusuke Konishi 47eb6b9c8f nilfs2: fix possible circular locking for get information ioctls
This is one of two patches which are to correct possible circular
locking between mm->mmap_sem and nilfs->ns_segctor_sem.

The problem was detected by lockdep check as follows:

 =======================================================
 [ INFO: possible circular locking dependency detected ]
 2.6.30-rc3-nilfs-00002-g3552613 #6
 -------------------------------------------------------
 mmap/5418 is trying to acquire lock:
 (&nilfs->ns_segctor_sem){++++.+}, at: [<d0d0e852>] nilfs_transaction_begin+0xb6/0x10c [nilfs2]

 but task is already holding lock:
 (&mm->mmap_sem){++++++}, at: [<c043700a>] do_page_fault+0x1d8/0x30a

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (&mm->mmap_sem){++++++}:
 [<c01470a5>] __lock_acquire+0x1066/0x13b0
 [<c01474a9>] lock_acquire+0xba/0xdd
 [<c01836bc>] might_fault+0x68/0x88
 [<c023c730>] copy_to_user+0x2c/0xfc
 [<d0d11b4f>] nilfs_ioctl_wrap_copy+0x103/0x160 [nilfs2]
 [<d0d11fa9>] nilfs_ioctl+0x30a/0x3b0 [nilfs2]
 [<c01a3be7>] vfs_ioctl+0x22/0x69
 [<c01a408e>] do_vfs_ioctl+0x460/0x499
 [<c01a4107>] sys_ioctl+0x40/0x5a
 [<c01031a4>] sysenter_do_call+0x12/0x38
 [<ffffffff>] 0xffffffff

 -> #0 (&nilfs->ns_segctor_sem){++++.+}:
 [<c0146e0b>] __lock_acquire+0xdcc/0x13b0
 [<c01474a9>] lock_acquire+0xba/0xdd
 [<c0433f1d>] down_read+0x2a/0x3e
 [<d0d0e852>] nilfs_transaction_begin+0xb6/0x10c [nilfs2]
 [<d0cfe0e5>] nilfs_page_mkwrite+0xe7/0x154 [nilfs2]
 [<c0183b0b>] __do_fault+0x165/0x376
 [<c01855cd>] handle_mm_fault+0x287/0x5d1
 [<c043712d>] do_page_fault+0x2fb/0x30a
 [<c0435462>] error_code+0x72/0x78
 [<ffffffff>] 0xffffffff

 other info that might help us debug this:

 1 lock held by mmap/5418:
 #0:  (&mm->mmap_sem){++++++}, at: [<c043700a>] do_page_fault+0x1d8/0x30a

 stack backtrace:
 Pid: 5418, comm: mmap Not tainted 2.6.30-rc3-nilfs-00002-g3552613 #6
 Call Trace:
 [<c0432145>] ? printk+0xf/0x12
 [<c0145c48>] print_circular_bug_tail+0xaa/0xb5
 [<c0146e0b>] __lock_acquire+0xdcc/0x13b0
 [<d0d10149>] ? nilfs_sufile_get_stat+0x1e/0x105 [nilfs2]
 [<c013b59a>] ? up_read+0x16/0x2c
 [<d0d10225>] ? nilfs_sufile_get_stat+0xfa/0x105 [nilfs2]
 [<c01474a9>] lock_acquire+0xba/0xdd
 [<d0d0e852>] ? nilfs_transaction_begin+0xb6/0x10c [nilfs2]
 [<c0433f1d>] down_read+0x2a/0x3e
 [<d0d0e852>] ? nilfs_transaction_begin+0xb6/0x10c [nilfs2]
 [<d0d0e852>] nilfs_transaction_begin+0xb6/0x10c [nilfs2]
 [<d0cfe0e5>] nilfs_page_mkwrite+0xe7/0x154 [nilfs2]
 [<c0183b0b>] __do_fault+0x165/0x376
 [<c01855cd>] handle_mm_fault+0x287/0x5d1
 [<c043700a>] ? do_page_fault+0x1d8/0x30a
 [<c013b54f>] ? down_read_trylock+0x39/0x43
 [<c043712d>] do_page_fault+0x2fb/0x30a
 [<c0436e32>] ? do_page_fault+0x0/0x30a
 [<c0435462>] error_code+0x72/0x78
 [<c0436e32>] ? do_page_fault+0x0/0x30a

This makes the lock granularity of nilfs->ns_segctor_sem finer than
that of the mmap semaphore for ioctl commands except
nilfs_clean_segments().

The successive patch ("nilfs2: fix lock order reversal in
nilfs_clean_segments ioctl") is required to fully resolve the problem.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-05-11 12:57:46 +09:00
Ryusuke Konishi 843382370e nilfs2: ensure to clear dirty state when deleting metadata file block
This would fix the following failure during GC:

 nilfs_cpfile_delete_checkpoints: cannot delete block
 NILFS: GC failed during preparation: cannot delete checkpoints: err=-2

The problem was caused by a break in state consistency between page
cache and btree; the above block was removed from the btree but the
page buffering the block was remaining in the page cache in dirty
state.

This resolves the inconsistency by ensuring to clear dirty state of
the page buffering the deleted block.

Reported-by: David Arendt <admin@prnet.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-05-10 17:04:42 +09:00
Ryusuke Konishi 201913ed74 nilfs2: fix circular locking dependency of writer mutex
This fixes the following circular locking dependency problem:

 =======================================================
 [ INFO: possible circular locking dependency detected ]
 2.6.30-rc3 #5
 -------------------------------------------------------
 segctord/3895 is trying to acquire lock:
  (&nilfs->ns_writer_mutex){+.+...}, at: [<d0d02172>]
   nilfs_mdt_get_block+0x89/0x20f [nilfs2]

 but task is already holding lock:
  (&bmap->b_sem){++++..}, at: [<d0d02d99>]
   nilfs_bmap_propagate+0x14/0x2e [nilfs2]

 which lock already depends on the new lock.

The bugfix is done by replacing call sites of nilfs_get_writer() which
are never called from read-only context with direct dereferencing of
pointer to a writable FS-instance.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-05-09 13:36:57 +09:00
Ryusuke Konishi 85c2a74fab nilfs2: fix possible recovery failure due to block creation without writer
Some function calls in nilfs_prepare_segment_for_recovery() may fail
because they can create blocks on meta data files without configuring
a writable FS-instance.  Concretely, nilfs_mdt_create_block() routine
of meta data files will fail in that case.

This fixes the problem by temporarily attaching a writable FS-instace
during the function is called.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-05-09 13:36:56 +09:00
Ryusuke Konishi c85399c2da nilfs2: fix possible mismatch of sufile counters on recovery
On-disk counters ndirtysegs and ncleansegs of sufile, can go wrong
after roll-forward recovery because
nilfs_prepare_segment_for_recovery() function marks segments dirty
without adjusting value of these counters.

This fixes the problem by adding a function to sufile which does the
operation adjusting the counters, and by letting the recovery function
use it.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-04-13 09:53:52 +09:00
Ryusuke Konishi a703018f7b nilfs2: segment usage file cleanups
This will simplify sufile.c by sharing common code which repeatedly
appears in routines updating a segment usage entry; a wrapper function
nilfs_sufile_update() is introduced for the purpose, and counter
modifications are integrated to a new function
nilfs_sufile_mod_counter().

This is a preparation for the successive bugfix patch ("nilfs2: fix
possible mismatch of sufile counters on recovery").

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-04-13 09:53:51 +09:00
Ryusuke Konishi 88072faf9a nilfs2: fix wrong accounting and duplicate brelse in nilfs_sufile_set_error
The nilfs_sufile_set_error() function wrongly adjusts the number of
dirty segments instead of the number of clean segments.  In addition,
the function calls brelse() twice for the same buffer head.

This fixes these bugs.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-04-13 09:53:51 +09:00
Ryusuke Konishi 3efb55b496 nilfs2: simplify handling of active state of segments fix
This fixes a bug of ("nilfs2: simplify handling of active state of
segments") patch.  The patch did not take account that a base index is
increased in nilfs_sufile_get_suinfo() function if requested entries
go across block boundary on sufile.

Due to this bug, the active flag sometimes appears on wrong segments
and has induced malfunction of garbage collection.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-04-13 09:53:51 +09:00
Ryusuke Konishi e7a7402c0d nilfs2: remove module version
A MODULE_VERSION() macro has been used in out-of-tree nilfs modules,
but it's needless and not updated in tree.  So, this removes it along
with the version declaration.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-04-13 09:53:50 +09:00
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 #26
---------------------------------------------
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 bcb48891b0 nilfs2: fix lockdep recursive locking warning on bmap
The bmap semaphore of DAT file can be held while a bmap of other files
is locked.  This has caused the following false detection of lockdep
check:

mount.nilfs2/4667 is trying to acquire lock:
 (&bmap->b_sem){..--}, at: [<d0c6c4b4>] nilfs_bmap_lookup_at_level+0x1a/0x74 [nilfs2]

but task is already holding lock:
 (&bmap->b_sem){..--}, at: [<d0c6c4b4>] nilfs_bmap_lookup_at_level+0x1a/0x74 [nilfs2]

This will fix the false detection by distinguishing semaphores of the
DAT and other files.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-04-13 09:53:49 +09:00
Ryusuke Konishi c306af23e1 nilfs2: return f_fsid for statfs2
This follows the change of Coly Li's series ("fs: return f_fsid for
statfs(2)"), and make nilfs2 return f_fsid info for statfs(2).

Acked-by: Coly Li <coly.li@suse.de>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-04-13 09:53:49 +09:00
Ryusuke Konishi 612392307c nilfs2: support nanosecond timestamp
After a review of user's feedback for finding out other compatibility
issues, I found nilfs improperly initializes timestamps in inode;
CURRENT_TIME was used there instead of CURRENT_TIME_SEC even though nilfs
didn't have nanosecond timestamps on disk.  A few users gave us the report
that the tar program sometimes failed to expand symbolic links on nilfs,
and it turned out to be the cause.

Instead of applying the above displacement, I've decided to support
nanosecond timestamps on this occation.  Fortunetaly, a needless 64-bit
field was in the nilfs_inode struct, and I found it's available for this
purpose without impact for the users.

So, this will do the enhancement and resolve the tar problem.

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 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 cece552074 nilfs2: simplify handling of active state of segments
will reduce some lines of segment constructor.  Previously, the state was
complexly controlled through a list of segments in order to keep
consistency in meta data of usage state of segments.  Instead, this
presents ``calculated'' active flags to userland cleaner program and stop
maintaining its real flag on disk.

Only by this fake flag, the cleaner cannot exactly know if each segment is
reclaimable or not.  However, the recent extension of nilfs_sustat ioctl
struct (nilfs2-extend-nilfs_sustat-ioctl-struct.patch) can prevent the
cleaner from reclaiming in-use segment wrongly.

So, now I can apply this for simplification.

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 c96fa464a5 nilfs2: mark minor flag for checkpoint created by internal operation
Nilfs creates checkpoints even for garbage collection or metadata updates
such as checkpoint mode change.  So, user often sees checkpoints created
only by such internal operations.

This is inconvenient in some situations.  For example, application that
monitors checkpoints and changes them to snapshots, will fall into an
infinite loop because it cannot distinguish internally created
checkpoints.

This patch solves this sort of problem by adding a flag to checkpoint for
identification.

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 458c5b0822 nilfs2: clean up sketch file
The sketch file is a file to mark checkpoints with user data.  It was
experimentally introduced in the original implementation, and now
obsolete.  The file was handled differently with regular files; the file
size got truncated when a checkpoint was created.

This stops the special treatment and will treat it as a regular file.
Most users are not affected because mkfs.nilfs2 no longer makes this file.

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 e626874685 nilfs2: super block operations fix endian bug
This adds a missing endian conversion of checksum field in the super
block.  This fixes compatibility issue on big endian machines which will
come to surface after supporting recovery of super block.

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 1f5abe7e7d nilfs2: replace BUG_ON and BUG calls triggerable from ioctl
Pekka Enberg advised me:
> It would be nice if BUG(), BUG_ON(), and panic() calls would be
> converted to proper error handling using WARN_ON() calls. The BUG()
> call in nilfs_cpfile_delete_checkpoints(), for example, looks to be
> triggerable from user-space via the ioctl() system call.

This will follow the comment and keep them to a minimum.

Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
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 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 7a9461939a nilfs2: use unlocked_ioctl
Pekka Enberg suggested converting ->ioctl operations to use
->unlocked_ioctl to avoid BKL.

The conversion was verified to be safe, so I will take it on this
occasion.

Cc: Pekka Enberg <penberg@cs.helsinki.fi>
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 8082d36aed nilfs2: remove compat ioctl code
This removes compat code from the nilfs ioctls and applies the same
function for both .ioctl and .compat_ioctl file operations.

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 dc498d09be nilfs2: use fixed sized types for ioctl structures
Nilfs ioctl had structures not having fixed sized types such as:

  struct nilfs_argv {
         void *v_base;
         size_t v_nmembs;
         size_t v_size;
         int v_index;
         int v_flags;
  };

Further, some of them are wrongly aligned:

  e.g.

  struct nilfs_cpmode {
        __u64 cm_cno;
        int cm_mode;
  };

The size of wrongly aligned structures varies depending on
architectures, and it breaks the identity of ioctl commands, which
leads to arch dependent errors.

Previously, these are compensated by using compat_ioctl.

This fixes these problems and allows removal of compat ioctl.

Since this will change sizes of those structures, binary compatibility
for the past utilities will once break; new utilities have to be used
instead.  However, it would be helpful to avoid platform dependent
problems in the long term.

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 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 76068c4ff1 nilfs2: fix buggy behavior seen in enumerating checkpoints
This will fix the weird behavior of lscp command in listing continuously
created checkpoints; the output of lscp is rewinded regularly for the
recent nilfs.  As a result of debugging, a defect was found in
nilfs_cpfile_do_get_cpinfo() function.

Though the function can be repeatedly called to enumerate checkpoints and
it can skip invalid checkpoint entries, the index value was not carried
between successive calls.

The bug has long been present, and came to surface after applying a bugfix
nilfs2-fix-problems-of-memory-allocation-in-ioctl.patch, which increased
frequency of calling the function.  The similar bugfix was already applied
for ``snapshots'' by
nilfs2-fix-gc-failure-on-volumes-keeping-numerous-snapshots.patch.

This fixes the problem by making the index argument bidirectional on the
function.

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
Pekka Enberg 8acfbf0939 nilfs2: clean up indirect function calling conventions
This cleans up the strange indirect function calling convention used in
nilfs to follow the normal kernel coding style.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
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>
2009-04-07 08:31:17 -07:00
Ryusuke Konishi 7fa10d2001 nilfs2: fix improper return values of nilfs_get_cpinfo ioctl
A few tool developers gave me requests for fixing inconvenient return
value of nilfs_get_cpinfo() ioctl; if the requested mode is NILFS_SNAPSHOT
and the specified start entry is not a snapshot, the ioctl unnaturally
returns one as the number of acquired snapshot item.

In addition, the ioctl function returns an ENOENT error for checkpoints
within blocks deleted by garbage collection.

These behaviors require corrections for programs which enumerate
snapshots.  This resolves the inconvenience by changing the return values
to zero for the above cases.

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 08:31:17 -07:00
Ryusuke Konishi b028fcfc4c nilfs2: fix gc failure on volumes keeping numerous snapshots
This resolves the following failure of nilfs2 cleaner daemon:

 nilfs_cleanerd[20670]: cannot clean segments: No such file or directory
 nilfs_cleanerd[20670]: shutdown

When creating thousands of snapshots, the cleaner daemon had rarely died
as above due to an error returned from the kernel code.

After applying the recent patch which fixed memory allocation problems in
ioctl (Message-Id: <20081215.155840.105124170.ryusuke@osrg.net>), the
problem gets more frequent.

It turned out to be a bug of nilfs_ioctl_wrap_copy function and one of its
callback routines to read out information of snapshots; if the
nilfs_ioctl_wrap_copy function divided a large read request into multiple
requests, the second and later requests have failed since a restart
position on snapshot meta data was not properly set forward.

It's a deficiency of the callback interface that cannot pass the restart
position among multiple requests.  This patch fixes the issue by allowing
nilfs_ioctl_wrap_copy and snapshot read functions to exchange a position
argument.

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 08:31:17 -07:00
Ryusuke Konishi 047180f2d7 nilfs2: insert explanations in gcinode file
The file gcinode.c gives buffer cache functions for on-disk blocks
moved in garbage collection.  Joern Engel has suggested inserting its
explanations in the source file (Message-ID:
<20080917144146.GD8750@logfs.org> and
<20080917224953.GB14644@logfs.org>).

This follows the comment.

Cc: Joern Engel <joern@logfs.org>
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 08:31:17 -07:00
Ryusuke Konishi 47420c7998 nilfs2: avoid double error caused by nilfs_transaction_end
Pekka Enberg pointed out that double error handlings found after
nilfs_transaction_end() can be avoided by separating abort operation:

 OK, I don't understand this. The only way nilfs_transaction_end() can
 fail is if we have NILFS_TI_SYNC set and we fail to construct the
 segment. But why do we want to construct a segment if we don't commit?

 I guess what I'm asking is why don't we have a separate
 nilfs_transaction_abort() function that can't fail for the erroneous
 case to avoid this double error value tracking thing?

This does the separation and renames nilfs_transaction_end() to
nilfs_transaction_commit() for clarification.

Since, some calls of these functions were used just for exclusion control
against the segment constructor, they are replaced with semaphore
operations.

Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
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 08:31:17 -07:00
Ryusuke Konishi a2e7d2df82 nilfs2: cleanup nilfs_clear_inode
This will remove the following unnecessary locks and cleanup code in
nilfs_clear_inode():

- unnecessary protection using nilfs_transaction_begin() and
  nilfs_transaction_end().

- cleanup code of i_dirty list field which is never chained
  when this function is called.

- spinlock used when releasing i_bh field.

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 08:31:17 -07:00
Ryusuke Konishi 3358b4aaa8 nilfs2: fix problems of memory allocation in ioctl
This is another patch for fixing the following problems of a memory
copy function in nilfs2 ioctl:

(1) It tries to allocate 128KB size of memory even for small objects.

(2) Though the function repeatedly tries large memory allocations
    while reducing the size, GFP_NOWAIT flag is not specified.
    This increases the possibility of system memory shortage.

(3) During the retries of (2), verbose warnings are printed
    because _GFP_NOWARN flag is not used for the kmalloc calls.

The first patch was still doing large allocations by kmalloc which are
repeatedly tried while reducing the size.

Andi Kleen told me that using copy_from_user for large memory is not
good from the viewpoint of preempt latency:

 On Fri, 12 Dec 2008 21:24:11 +0100, Andi Kleen <andi@firstfloor.org> wrote:
 > > In the current interface, each data item is copied twice: one is to
 > > the allocated memory from user space (via copy_from_user), and another
 >
 > For such large copies it is better to use multiple smaller (e.g. 4K)
 > copy user, that gives better real time preempt latencies. Each cfu has a
 > cond_resched(), but only one, not multiple times in the inner loop.

He also advised me that:

 On Sun, 14 Dec 2008 16:13:27 +0100, Andi Kleen <andi@firstfloor.org> wrote:
 > Better would be if you could go to PAGE_SIZE. order 0 allocations
 > are typically the fastest / least likely to stall.
 >
 > Also in this case it's a good idea to use __get_free_pages()
 > directly, kmalloc tends to be become less efficient at larger
 > sizes.

For the function in question, the size of buffer memory can be reduced
since the buffer is repeatedly used for a number of small objects.  On
the other hand, it may incur large preempt latencies for larger buffer
because a copy_from_user (and a copy_to_user) was applied only once
each cycle.

With that, this revision uses the order 0 allocations with
__get_free_pages() to fix the original problems.

Cc: Andi Kleen <andi@firstfloor.org>
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 08:31:16 -07:00
Ryusuke Konishi 0c4fb87764 nilfs2: update makefile and Kconfig
This adds a Makefile for the nilfs2 file system, and updates the
makefile and Kconfig file in the file system directory.

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 08:31:16 -07:00
Koji Sato 7942b919f7 nilfs2: ioctl operations
This adds userland interface implemented with ioctl.

Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
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 08:31:16 -07:00
Ryusuke Konishi a3d93f709e nilfs2: block cache for garbage collection
This adds the cache of on-disk blocks to be moved in garbage
collection.  The disk blocks are held with dummy inodes (called
gcinodes), and this file provides lookup function of the dummy inodes,
and their buffer read function.

Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Yoshiji Amagai <amagai.yoshiji@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 08:31:16 -07:00
Ryusuke Konishi 84ef1ecfde nilfs2: another dat for garbage collection
NILFS2 uses another DAT inode during garbage collection to ensure
atomicity and consistency of the DAT in the transient state.  This
twin inode is called GCDAT.

This adds functions to initialize the GCDAT and to switch page caches
and B-tree node caches between these two inodes.

Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Yoshiji Amagai <amagai.yoshiji@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 08:31:16 -07:00
Ryusuke Konishi 0f3e1c7f23 nilfs2: recovery functions
This adds recovery function on mount.

Usually the recovery is achieved by just finding the latest super
root.  When logs without checkpoints were appended for data sync
operations after the latest super root, the recovery function will
perform roll forwarding and reconstruct new log(s) with a super root.

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 08:31:16 -07:00
Ryusuke Konishi f30bf3e40f nilfs2: fix missed-sync issue for do_sync_mapping_range()
Chris Mason pointed out that there is a missed sync issue in
nilfs_writepages():

On Wed, 17 Dec 2008 21:52:55 -0500, Chris Mason wrote:
> It looks like nilfs_writepage ignores WB_SYNC_NONE, which is used by
> do_sync_mapping_range().

where WB_SYNC_NONE in do_sync_mapping_range() was replaced with
WB_SYNC_ALL by Nick's patch (commit:
ee53a891f4).

This fixes the problem by letting nilfs_writepages() write out the log of
file data within the range if sync_mode is WB_SYNC_ALL.

This involves removal of nilfs_file_aio_write() which was previously
needed to ensure O_SYNC sync writes.

Cc: Chris Mason <chris.mason@oracle.com>
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
Ryusuke Konishi 9ff05123e3 nilfs2: segment constructor
This adds the segment constructor (also called log writer).

The segment constructor collects dirty buffers for every dirty inode,
makes summaries of the buffers, assigns disk block addresses to the
buffers, and then submits BIOs for the buffers.

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
Ryusuke Konishi 64b5a32e0b nilfs2: segment buffer
This adds the segment buffer which is used to constuct logs.

[akpm@linux-foundation.org: BIO_RW_SYNC got removed]
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
Ryusuke Konishi 783f61843e nilfs2: super block operations
This adds super block operations for the nilfs2 file system.

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
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
Ryusuke Konishi d25006523d nilfs2: pathname operations
This adds pathname operations, most of which comes from the ext2 file
system.

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
Yoshiji Amagai 2ba466d74e nilfs2: directory entry operations
This adds directory handling functions, most of which comes from the ext2
file system.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Yoshiji Amagai <amagai.yoshiji@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
Ryusuke Konishi f183ff4f05 nilfs2: file operations
This adds primitives for regular file handling.

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 08:31:14 -07:00
Ryusuke Konishi 05fe58fdc1 nilfs2: inode operations
This adds inode level operations of the nilfs2 file system.

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 08:31:14 -07:00
Koji Sato 6c98cd4ecb nilfs2: segment usage file
This adds a meta data file which stores the allocation state of segments.

[konishi.ryusuke@lab.ntt.co.jp: fix wrong counting of checkpoints and dirty segments]
Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
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 08:31:14 -07:00
Koji Sato 2961980972 nilfs2: checkpoint file
This adds a meta data file which holds checkpoint entries in its data
blocks.

Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
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 08:31:14 -07:00
Ryusuke Konishi 43bfb45ed4 nilfs2: inode map file
This adds a meta data file which stores on-disk inodes in its data blocks.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Yoshiji Amagai <amagai.yoshiji@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 08:31:14 -07:00
Koji Sato a17564f58b nilfs2: disk address translator
This adds the disk address translation file (DAT) whose primary function
is to convert virtual disk block numbers to actual disk block numbers.

The virtual block numbers of NILFS are associated with checkpoint
generation numbers, and this file also provides functions to manage the
lifetime information of each virtual block number.

Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
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 08:31:14 -07:00
Ryusuke Konishi 5442680fd2 nilfs2: persistent object allocator
This adds common functions to allocate or deallocate entries with bitmaps
on a meta data file.  This feature is used by the DAT and ifile.

Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Yoshiji Amagai <amagai.yoshiji@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 08:31:13 -07:00
Ryusuke Konishi 5eb563f5f2 nilfs2: meta data file
This adds the meta data file, which serves common buffer functions to the
DAT, sufile, cpfile, ifile, and so forth.

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 08:31:13 -07:00
Ryusuke Konishi 0bd49f9446 nilfs2: buffer and page operations
This adds common routines for buffer/page operations used in B-tree
node caches, meta data files, or segment constructor (log writer).

NILFS uses copy functions for buffers and pages due to the following
reasons:

 1) Relocation required for COW
    Since NILFS changes address of on-disk blocks, moving buffers
    in page cache is needed for the buffers which are not addressed
    by a file offset.  If buffer size is smaller than page size,
    this involves partial copy of pages.

 2) Freezing mmapped pages
    NILFS calculates checksums for each log to ensure its validity.
    If page data changes after the checksum calculation, this validity
    check will not work correctly.  To avoid this failure for mmaped
    pages, NILFS freezes their data by copying.

 3) Copy-on-write for DAT pages
    NILFS makes clones of DAT page caches in a copy-on-write manner
    during GC processes, and this ensures atomicity and consistency
    of the DAT in the transient state.

In addition, NILFS uses two obsolete functions, nilfs_mark_buffer_dirty()
and nilfs_clear_page_dirty() respectively.

* nilfs_mark_buffer_dirty() was required to avoid NULL pointer
  dereference faults:

  Since the page cache of B-tree node pages or data page cache of pseudo
  inodes does not have a valid mapping->host, calling mark_buffer_dirty()
  for their buffers causes the fault; it calls __mark_inode_dirty(NULL)
  through __set_page_dirty().

* nilfs_clear_page_dirty() was needed in the two cases:

 1) For B-tree node pages and data pages of the dat/gcdat, NILFS2 clears
    page dirty flags when it copies back pages from the cloned cache
    (gcdat->{i_mapping,i_btnode_cache}) to its original cache
    (dat->{i_mapping,i_btnode_cache}).

 2) Some B-tree operations like insertion or deletion may dispose buffers
    in dirty state, and this needs to cancel the dirty state of their
    pages.  clear_page_dirty_for_io() caused faults because it does not
    clear the dirty tag on the page cache.

Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp>
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 08:31:13 -07:00
Ryusuke Konishi a60be987d4 nilfs2: B-tree node cache
This adds routines for B-tree node buffers.

Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp>
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 08:31:13 -07:00
Koji Sato 36a580eb48 nilfs2: direct block mapping
This adds block mappings using direct pointers which are stored in the
i_bmap array of inode.

Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
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 08:31:13 -07:00
Koji Sato 17c76b0104 nilfs2: B-tree based block mapping
This adds declarations and functions of NILFS2 B-tree.

Two variants are integrated in the NILFS2 B-tree.  The B-tree for the most
files points to the child nodes or data blocks with virtual block
addresses, whereas the B-tree of the DAT uses actual block addresses.

Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
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 08:31:13 -07:00
Koji Sato bdb265eae0 nilfs2: integrated block mapping
This adds structures and operations for the block mapping (bmap for
short).  NILFS2 uses direct mappings for short files or B-tree based
mappings for longer files.

Every on-disk data block is held with inodes and managed through this
block mapping.  The nilfs_bmap structure and a set of functions here
provide this capability to the NILFS2 inode.

[penberg@cs.helsinki.fi: remove a bunch of bmap wrapper macros]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 08:31:13 -07:00
Ryusuke Konishi 65b4643d3b nilfs2: add inode and other major structures
This adds the following common structures of the NILFS2 file system.

* nilfs_inode_info structure:
  gives on-memory inode.

* nilfs_sb_info structure:
  keeps per-mount state and a special inode for the ifile.
  This structure is attached to the super_block structure.

* the_nilfs structure:
  keeps shared state and locks among a read/write mount and snapshot
  mounts.  This keeps special inodes for the sufile, cpfile, dat, and
  another dat inode used during GC (gcdat).  This also has a hash table
  of dummy inodes to cache disk blocks during GC (gcinodes).

* nilfs_transaction_info structure:
  keeps per task state while nilfs is writing logs or doing indivisible
  inode or namespace operations.  This structure is used to identify
  context during log making and store nest level of the lock which
  ensures atomicity of file system operations.

Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
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 08:31:12 -07:00