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path: root/fs/nilfs2/super.c
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2010-10-23nilfs2: simplify life cycle management of nilfs objectRyusuke Konishi1-45/+22
This stops pre-allocating nilfs object in nilfs_get_sb routine, and stops managing its life cycle by reference counting. nilfs_find_or_create_nilfs() function, nilfs->ns_mount_mutex, nilfs_objects list, and the reference counter will be removed through the simplification. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: do not allocate multiple super block instances for a deviceRyusuke Konishi1-116/+100
This stops allocating multiple super block instances for a device. All snapshots and a current mode mount (i.e. latest tree) will be controlled with nilfs_root objects that are kept within an sb instance. nilfs_get_sb() is rewritten so that it always has a root object for the latest tree and snapshots make additional root objects. The root dentry of the latest tree is binded to sb->s_root even if it isn't attached on a directory. Root dentries of snapshots or the latest tree are binded to mnt->mnt_root on which they are mounted. With this patch, nilfs_find_sbinfo() function, nilfs->ns_supers list, and nilfs->ns_current back pointer, are deleted. In addition, init_nilfs() and load_nilfs() are simplified since they will be called once for a device, not repeatedly called for mount points. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: split out nilfs_attach_snapshotRyusuke Konishi1-28/+45
This splits the code to attach snapshots into a separate routine for convenience sake. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: split out nilfs_get_root_dentryRyusuke Konishi1-19/+35
This splits the code to allocate root dentry into a separate routine for convenience in successive changes. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: move inode count and block count into root objectRyusuke Konishi1-5/+6
This moves sbi->s_inodes_count and sbi->s_blocks_count into nilfs_root object. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: use root object to get ifileRyusuke Konishi1-29/+13
This rewrites functions using ifile so that they get ifile from nilfs_root object, and will remove sbi->s_ifile. Some functions that don't know the root object are extended to receive it from caller. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: make snapshots in checkpoint tree exportableRyusuke Konishi1-51/+1
The previous export operations cannot handle multiple versions of a filesystem if they belong to the same sb instance. This adds a new type of file handle and extends export operations so that they can get the inode specified by a checkpoint number as well as an inode number and a generation number. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: set pointer to root object in inodesRyusuke Konishi1-7/+30
This puts a pointer to nilfs_root object in the private part of on-memory inode, and makes nilfs_iget function pick up the inode with the same root object. Non-root inodes inherit its nilfs_root object from parent inode. That of the root inode is allocated through nilfs_attach_checkpoint() function. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: use iget5_locked to get inodeRyusuke Konishi1-0/+1
This uses iget5_locked instead of iget_locked so that gc cache can look up inodes with an inode number and an optional checkpoint number. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: allow nilfs_destroy_inode to destroy metadata file inodesRyusuke Konishi1-0/+6
The current nilfs_destroy_inode() doesn't handle metadata file inodes including gc inodes (dummy inodes used for garbage collection). This allows nilfs_destroy_inode() to destroy inodes of metadata files. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-04BKL: Remove BKL from NILFS2Jan Blunck1-17/+1
The BKL is only used in put_super, fill_super and remount_fs that are all three protected by the superblocks s_umount rw_semaphore. Therefore it is safe to remove the BKL entirely. Signed-off-by: Jan Blunck <jblunck@infradead.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-10-04BKL: Explicitly add BKL around get_sb/fill_superJan Blunck1-1/+7
This patch is a preparation necessary to remove the BKL from do_new_mount(). It explicitly adds calls to lock_kernel()/unlock_kernel() around get_sb/fill_super operations for filesystems that still uses the BKL. I've read through all the code formerly covered by the BKL inside do_kern_mount() and have satisfied myself that it doesn't need the BKL any more. do_kern_mount() is already called without the BKL when mounting the rootfs and in nfsctl. do_kern_mount() calls vfs_kern_mount(), which is called from various places without BKL: simple_pin_fs(), nfs_do_clone_mount() through nfs_follow_mountpoint(), afs_mntpt_do_automount() through afs_mntpt_follow_link(). Both later functions are actually the filesystems follow_link inode operation. vfs_kern_mount() is calling the specified get_sb function and lets the filesystem do its job by calling the given fill_super function. Therefore I think it is safe to push down the BKL from the VFS to the low-level filesystems get_sb/fill_super operation. [arnd: do not add the BKL to those file systems that already don't use it elsewhere] Signed-off-by: Jan Blunck <jblunck@infradead.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-18Merge branch 'for-linus' of ↵Linus Torvalds1-14/+14
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: fs: brlock vfsmount_lock fs: scale files_lock lglock: introduce special lglock and brlock spin locks tty: fix fu_list abuse fs: cleanup files_lock locking fs: remove extra lookup in __lookup_hash fs: fs_struct rwlock to spinlock apparmor: use task path helpers fs: dentry allocation consolidation fs: fix do_lookup false negative mbcache: Limit the maximum number of cache entries hostfs ->follow_link() braino hostfs: dumb (and usually harmless) tpyo - strncpy instead of strlcpy remove SWRITE* I/O types kill BH_Ordered flag vfs: update ctime when changing the file's permission by setfacl cramfs: only unlock new inodes fix reiserfs_evict_inode end_writeback second call
2010-08-18kill BH_Ordered flagChristoph Hellwig1-14/+14
Instead of abusing a buffer_head flag just add a variant of sync_dirty_buffer which allows passing the exact type of write flag required. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-16nilfs2: fix list corruption after ifile creation failureRyusuke Konishi1-1/+3
If nilfs_attach_checkpoint() gets a memory allocation failure during creation of ifile, it will return without removing nilfs_sb_info struct from ns_supers list. When a concurrently mounted snapshot is unmounted or another new snapshot is mounted after that, this causes kernel oops as below: > BUG: unable to handle kernel NULL pointer dereference at (null) > IP: [<f83662ff>] nilfs_find_sbinfo+0x74/0xa4 [nilfs2] > *pde = 00000000 > Oops: 0000 [#1] SMP <snip> > Call Trace: > [<f835dc29>] ? nilfs_get_sb+0x165/0x532 [nilfs2] > [<c1173c87>] ? ida_get_new_above+0x16d/0x187 > [<c109a7f8>] ? alloc_vfsmnt+0x7e/0x10a > [<c1070790>] ? kstrdup+0x2c/0x40 > [<c1089041>] ? vfs_kern_mount+0x96/0x14e > [<c108913d>] ? do_kern_mount+0x32/0xbd > [<c109b331>] ? do_mount+0x642/0x6a1 > [<c101a415>] ? do_page_fault+0x0/0x2d1 > [<c1099c00>] ? copy_mount_options+0x80/0xe2 > [<c10705d8>] ? strndup_user+0x48/0x67 > [<c109b3f1>] ? sys_mount+0x61/0x90 > [<c10027cc>] ? sysenter_do_call+0x12/0x22 This fixes the problem. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Tested-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: stable@kernel.org
2010-08-10Merge branch 'for-linus' of ↵Linus Torvalds1-19/+1
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: (96 commits) no need for list_for_each_entry_safe()/resetting with superblock list Fix sget() race with failing mount vfs: don't hold s_umount over close_bdev_exclusive() call sysv: do not mark superblock dirty on remount sysv: do not mark superblock dirty on mount btrfs: remove junk sb_dirt change BFS: clean up the superblock usage AFFS: wait for sb synchronization when needed AFFS: clean up dirty flag usage cifs: truncate fallout mbcache: fix shrinker function return value mbcache: Remove unused features add f_flags to struct statfs(64) pass a struct path to vfs_statfs update VFS documentation for method changes. All filesystems that need invalidate_inode_buffers() are doing that explicitly convert remaining ->clear_inode() to ->evict_inode() Make ->drop_inode() just return whether inode needs to be dropped fs/inode.c:clear_inode() is gone fs/inode.c:evict() doesn't care about delete vs. non-delete paths now ... Fix up trivial conflicts in fs/nilfs2/super.c
2010-08-10convert nilfs2 to ->evict_inode()Al Viro1-19/+1
[folded build fix from sfr] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-07-23nilfs2: reject incompatible filesystemRyusuke Konishi1-0/+39
This forces nilfs to check compatibility of feature flags so as to reject a filesystem with unknown features when it mounts or remounts the filesystem. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: get rid of nilfs_bmap_unionRyusuke Konishi1-1/+3
This removes nilfs_bmap_union and finally unifies three structures and the union in bmap/btree code into one. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: pass remount flag to parse_optionsRyusuke Konishi1-23/+26
This adds is_remount argument to the parse_options() function that obtains mount options from strings. Previously, parse_options did not distinguish context whether it's called for a new mount or remount, so the caller needed additional verifications outside the function. This allows parse_options to verify options and print messages depending on the context. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: use seq_puts to print mount options without argumentRyusuke Konishi1-6/+6
This replaces seq_printf() with seq_puts() in nilfs_show_options for mount options which have no argument. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: add nodiscard mount optionRyusuke Konishi1-1/+5
Nilfs has "discard" mount option which issues discard/TRIM commands to underlying block device, but it lacks a complementary option and has no way to disable the feature through remount. This adds "nodiscard" option to resolve this imbalance. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: add barrier mount optionRyusuke Konishi1-1/+5
Nilfs enables write barriers by default and has "nobarrier" mount option to disable this feature. But it lacks the complementary option and has no way to re-enable the feature on remount. This adds "barrier" option to resolve this imbalance. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: sync super blocks in turnsJiro SEKIBA1-30/+65
This will sync super blocks in turns instead of syncing duplicate super blocks at the time. This will help searching valid super root when super block is written into disk before log is written, which is happen when barrier-less block devices are unmounted uncleanly. In the situation, old super block likely points to valid log. This patch introduces ns_sbwcount member to the nilfs object and adds nilfs_sb_will_flip() function; ns_sbwcount counts how many times super blocks write back to the disk. And, nilfs_sb_will_flip() decides whether flipping required or not based on the count of ns_sbwcount to sync super blocks asymmetrically. The following functions are also changed: - nilfs_prepare_super(): flips super blocks according to the argument. The argument is calculated by nilfs_sb_will_flip() function. - nilfs_cleanup_super(): sets "clean" flag to both super blocks if they point to the same checkpoint. To update both of super block information, caller of nilfs_commit_super must set the information on both super blocks. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: introduce nilfs_prepare_superJiro SEKIBA1-22/+51
This function checks validity of super block pointers. If first super block is invalid, it will swap the super blocks. The function should be called before any super block information updates. Caller must obtain nilfs->ns_sem. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: separate function that updates log positionRyusuke Konishi1-13/+17
This moves out section that updates information of the recent log position stored in super blocks from nilfs_commit_super to a new routine named nilfs_set_log_cursor. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: add nilfs_set_errorRyusuke Konishi1-10/+14
This function marks error state and write it on super blocks. This is a preparation for making super block writeback alternately. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: add nilfs_cleanup_superRyusuke Konishi1-8/+20
This function write out filesystem state to super blocks in order to share the same cleanup work. This is a preparation for making super block writeback alternately. Cc: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23nilfs2: do not update mount time on rw->ro remountRyusuke Konishi1-1/+0
Mount time field in super block is wrongly updated when nilfs remounts the partition from read-write to read-only. This fixes the issue. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-31nilfs2: fix style issue in nilfs_destroy_cachepRyusuke Konishi1-4/+4
This gets rid of unwanted space chars in front of conditional sentences of nilfs_destroy_cachep(). Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: disallow remount of snapshot from/to a regular mountRyusuke Konishi1-34/+23
Snapshots and regular ro/rw mounts are essentially-different within the meaning whether the checkpoint is static or not and is marked with a snapshot flag or not. The current implemenation, however, allows to remount a snapshot to a regular rw-mount if the checkpoint number equals the latest one. This transition is actually impossible since changing a checkpoint to a snapshot makes another checkpoint, thus the condition is never satisfied. This fixes the weird state of affairs, and specifically separates snapshots and regular rw/ro-mounts. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: update comment on deactivate_super at nilfs_get_sbRyusuke Konishi1-1/+1
deactivate_super was replaced with deactivate_locked_super, but the comment of nilfs_get_sb remain unchanged. This renews the comment. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: replace MS_VERBOSE with MS_SILENTRyusuke Konishi1-1/+2
MS_VERBOSE is deprecated. This replaces it with MS_SILENT in reference to get_sb_bdev function. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: add missing initialization of s_modeRyusuke Konishi1-0/+1
An fmode_t argument is passed to kill_block_super() through s_mode member of the super_block structure. This is used to release the block device with the same mode, however, nilfs does not set s_mode anywhere. This modifies nilfs_get_sb function to properly initialize the s_mode member. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: fix misuse of open_bdev_exclusive/close_bdev_exclusiveRyusuke Konishi1-3/+7
The second argument of open_bdev_exclusive/close_bdev_exclusive takes fmode_t flags instead of mount flags. This fixes the misuse. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: add missing endian conversion on super block magic numberRyusuke Konishi1-2/+2
This adds missing endian conversions in comparision of the magic number of super blocks. It was coincidence that prior versions didn't incur problems; the upper byte of the magic number happened to be equal to the lower byte. But, semantically it's wrong to depend on this. This won't change anything else nor suffer any compatibility issues. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: add a print message after loading nilfs2Li Hong1-0/+1
Printing a message after loading a file system is a practice. Add this to provide a better user-friendly experience. Signed-off-by: Li Hong <lihong.hi@gmail.com> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: cleanup multi kmem_cache_{create,destroy} codeLi Hong1-60/+74
This cleanup patch gives several improvements: - Moving all kmem_cache_{create_destroy} calls into one place, which removes some small function calls, cleans up error check code and clarify the logic. - Mark all initial code in __init section. - Remove some very obvious comments. - Adjust some declarations. - Fix some space-tab issues. Signed-off-by: Li Hong <lihong.hi@gmail.com> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10nilfs2: change default of 'errors' mount option to 'remount-ro' modeRyusuke Konishi1-3/+3
Like ext3, nilfs has 'errors' mount option to allow specifying desired behavior on severe errors. Currently, the default action is 'errors=continue' and has potential to advance filesystem corruption for severe errors. This will change the action to 'errors=remount-ro' to avoid the issue. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-03nilfs2: fix sync silent failureRyusuke Konishi1-0/+1
As of 32a88aa1, __sync_filesystem() will return 0 if s_bdi is not set. And nilfs does not set s_bdi anywhere. I noticed this problem by the warning introduced by the recent commit 5129a469 ("Catch filesystem lacking s_bdi"). WARNING: at fs/super.c:959 vfs_kern_mount+0xc5/0x14e() Hardware name: PowerEdge 2850 Modules linked in: nilfs2 loop tpm_tis tpm tpm_bios video shpchp pci_hotplug output dcdbas Pid: 3773, comm: mount.nilfs2 Not tainted 2.6.34-rc6-debug #38 Call Trace: [<c1028422>] warn_slowpath_common+0x60/0x90 [<c102845f>] warn_slowpath_null+0xd/0x10 [<c1095936>] vfs_kern_mount+0xc5/0x14e [<c1095a03>] do_kern_mount+0x32/0xbd [<c10a811e>] do_mount+0x671/0x6d0 [<c1073794>] ? __get_free_pages+0x1f/0x21 [<c10a684f>] ? copy_mount_options+0x2b/0xe2 [<c107b634>] ? strndup_user+0x48/0x67 [<c10a81de>] sys_mount+0x61/0x8f [<c100280c>] sysenter_do_call+0x12/0x32 This ensures to set s_bdi for nilfs and fixes the sync silent failure. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Acked-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-14nilfs2: remove whitespaces before quoted newlinesRyusuke Konishi1-1/+1
This kills the following checkpatch warnings: WARNING: unnecessary whitespace before a quoted newline #869: FILE: super.c:869: + "remount to a different snapshot. \n", WARNING: unnecessary whitespace before a quoted newline #389: FILE: the_nilfs.c:389: + printk(KERN_ERR "NILFS: too short segment. \n"); Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-03-14nilfs2: fix various typos in commentsRyusuke Konishi1-1/+1
This fixes various typos I found in comments of nilfs2. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-13nilfs2: get rid of s_dirt flag useRyusuke Konishi1-2/+2
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>
2010-02-13nilfs2: fix potential hang in nilfs_error on errors=remount-roRyusuke Konishi1-3/+0
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>
2010-02-13nilfs2: issue discard request after cleaning segmentsJiro SEKIBA1-1/+7
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>
2009-12-16switch nilfs2 to deactivate_locked_super()Al Viro1-2/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-11-20nilfs2: add norecovery mount optionRyusuke Konishi1-1/+15
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>
2009-11-20nilfs2: move recovery completion into load_nilfs functionRyusuke Konishi1-34/+5
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>
2009-11-20nilfs2: hide nilfs_mdt_clear calls in nilfs_mdt_destroyRyusuke Konishi1-1/+0
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>
2009-11-20nilfs2: separate constructor of metadata filesRyusuke Konishi1-5/+1
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>