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path: root/fs/nilfs2/nilfs.h
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2012-12-20nilfs2: drop vmtruncateMarco Stornelli
Removed vmtruncate Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-31nilfs2: add omitted comments for different structures in driver implementationVyacheslav Dubeyko
Add omitted comments for different structures in driver implementation. Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.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>
2012-01-04nilfs: propagate umode_tAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-11-01treewide: use __printf not __attribute__((format(printf,...)))Joe Perches
Standardize the style for compiler based printf format verification. Standardized the location of __printf too. Done via script and a little typing. $ grep -rPl --include=*.[ch] -w "__attribute__" * | \ grep -vP "^(tools|scripts|include/linux/compiler-gcc.h)" | \ xargs perl -n -i -e 'local $/; while (<>) { s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf\s*,\s*(.+)\s*,\s*(.+)\s*\)\s*\)\s*\)/__printf($1, $2)/g ; print; }' [akpm@linux-foundation.org: revert arch bits] Signed-off-by: Joe Perches <joe@perches.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-21fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlersJosef Bacik
Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20->permission() sanitizing: don't pass flags to ->permission()Al Viro
not used by the instances anymore. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-27fs: pass exact type of data dirties to ->dirty_inodeChristoph Hellwig
Tell the filesystem if we just updated timestamp (I_DIRTY_SYNC) or anything else, so that the filesystem can track internally if it needs to push out a transaction for fdatasync or not. This is just the prototype change with no user for it yet. I plan to push large XFS changes for the next merge window, and getting this trivial infrastructure in this window would help a lot to avoid tree interdependencies. Also remove incorrect comments that ->dirty_inode can't block. That has been changed a long time ago, and many implementations rely on it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-10nilfs2: always set back pointer to host inode in mapping->hostRyusuke Konishi
In the current nilfs, page cache for btree nodes and meta data files do not set a valid back pointer to the host inode in mapping->host. This will change it so that every address space in nilfs uses mapping->host to hold its host inode. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-05-10nilfs2: implement resize ioctlRyusuke Konishi
This adds resize ioctl which makes online resize possible. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-03-30nilfs2: fix whitespace coding style issuesNicolas Kaiser
Fixes whitespace coding style issues. Signed-off-by: Nicolas Kaiser <nikai@nikai.net> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-03-09nilfs2: get rid of nilfs_sb_info structureRyusuke Konishi
This directly uses sb->s_fs_info to keep a nilfs filesystem object and fully removes the intermediate nilfs_sb_info structure. With this change, the hierarchy of on-memory structures of nilfs will be simplified as follows: Before: super_block -> nilfs_sb_info -> the_nilfs -> cptree --+-> nilfs_root (current file system) +-> nilfs_root (snapshot A) +-> nilfs_root (snapshot B) : -> nilfs_sc_info (log writer structure) After: super_block -> the_nilfs -> cptree --+-> nilfs_root (current file system) +-> nilfs_root (snapshot A) +-> nilfs_root (snapshot B) : -> nilfs_sc_info (log writer structure) The reason why we didn't design so from the beginning is because the initial shape also differed from the above. The early hierachy was composed of "per-mount-point" super_block -> nilfs_sb_info pairs and a shared nilfs object. On the kernel 2.6.37, it was changed to the current shape in order to unify super block instances into one per device, and this cleanup became applicable as the result. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-03-09nilfs2: use sb instance instead of nilfs_sb_info structRyusuke Konishi
This replaces sbi uses with direct reference to sb instance. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-03-08nilfs2: record used amount of each checkpoint in checkpoint listRyusuke Konishi
This records the number of used blocks per checkpoint in each checkpoint entry of cpfile. Even though userland tools can get the block count via nilfs_get_cpinfo ioctl, it was not updated by the nilfs2 kernel code. This fixes the issue and makes it available for userland tools to calculate used amount per checkpoint. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Jiro SEKIBA <jir@unicus.jp>
2011-03-08nilfs2: add compat ioctlRyusuke Konishi
The current FS_IOC_GETFLAGS/SETFLAGS/GETVERSION will fail if application is 32 bit and kernel is 64 bit. This issue is avoidable by adding compat_ioctl method. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-03-08nilfs2: tighten restrictions on inode flagsRyusuke Konishi
Nilfs has few rectrictions on which flags may be set on which inodes like ext2/3/4 filesystems used to be. Specifically DIRSYNC may only be set on directories and IMMUTABLE and APPEND may not be set on links. Tighten that to disallow TOPDIR being set on non-directories and only NODUMP and NOATIME to be set on non-regular file, non-directories. This introduces a flags masking function like those of extN and uses it during inode creation. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-01-10nilfs2: unfold nilfs_dat_inode functionRyusuke Konishi
nilfs_dat_inode function was a wrapper to switch between normal dat inode and gcdat, a clone of the dat inode for garbage collection. This function got obsolete when the gcdat inode was removed, and now we can access the dat inode directly from a nilfs object. So, we will unfold the wrapper and remove it. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-01-10nilfs2: do not pass sbi to functions which can get it from inodeRyusuke Konishi
This removes argument for passing nilfs_sb_info structure from nilfs_set_file_dirty and nilfs_load_inode_block functions. We can get a pointer to the structure from inodes. [Stephen Rothwell <sfr@canb.auug.org.au>: fix conflict with commit b74c79e99389cd79b31fcc08f82c24e492e63c7e] Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-01-10nilfs2: fiemap supportRyusuke Konishi
This adds fiemap to nilfs. Two new functions, nilfs_fiemap and nilfs_find_uncommitted_extent are added. nilfs_fiemap() implements the fiemap inode operation, and nilfs_find_uncommitted_extent() helps to get a range of data blocks whose physical location has not been determined. nilfs_fiemap() collects extent information by looping through nilfs_bmap_lookup_contig and nilfs_find_uncommitted_extent routines. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-01-07fs: provide rcu-walk aware permission i_opsNick Piggin
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2010-10-23nilfs2: remove own inode allocator and destructor for metadata filesRyusuke Konishi
This finally removes own inode allocator and destructor functions for metadata files. Several routines, nilfs_mdt_new(), nilfs_mdt_new_common(), nilfs_mdt_clear(), nilfs_mdt_destroy(), and nilfs_alloc_inode_common() will be gone. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: see state of root dentry for mount check of snapshotsRyusuke Konishi
After applied the patch that unified sb instances, root dentry of snapshots can be left in dcache even after their trees are unmounted. The orphan root dentry/inode keeps a root object, and this causes false positive of nilfs_checkpoint_is_mounted function. This resolves the issue by having nilfs_checkpoint_is_mounted test whether the root dentry is busy or not. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: use iget for all metadata filesRyusuke Konishi
This makes use of iget5_locked to allocate or get inode for metadata files to stop using own inode allocator. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: get rid of GCDAT inodeRyusuke Konishi
This applies prepared rollback function and redirect function of metadata file to DAT file, and eliminates GCDAT inode. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: deny write access to inodes in snapshotsRyusuke Konishi
Snapshots of nilfs are read-only. After super block instances (sb) will be unified, nilfs will need to check write access by a way other than implicit test with IS_RDONLY(inode). This is because IS_RDONLY() refers to MS_RDONLY bit of inode->i_sb->s_flags and it will become inaccurate after the unification of sb. To prepare for the issue, this uses i_op->permission to deny write access to inodes in snapshots. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-10-23nilfs2: use root object to get ifileRyusuke Konishi
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 Konishi
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 Konishi
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: remove own inode hash used for GCRyusuke Konishi
This uses inode hash function that vfs provides instead of the own hash table for caching gc inodes. This finally removes the own inode hash from nilfs. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-08-10Merge branch 'for-linus' of ↵Linus Torvalds
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
2010-08-09convert nilfs2 to ->evict_inode()Al Viro
[folded build fix from sfr] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-07-23nilfs2: reject incompatible filesystemRyusuke Konishi
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 Konishi
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: sync super blocks in turnsJiro SEKIBA
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 SEKIBA
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 Konishi
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_cleanup_superRyusuke Konishi
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>
2010-05-28drop unused dentry argument to ->fsyncChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03nilfs really shouldn't slap struct dentry on stack...Al Viro
... especially when it only needs (and initializes) .d_name of it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-10-01const: constify remaining file_operationsAlexey Dobriyan
[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>
2009-09-22const: mark remaining inode_operations as constAlexey Dobriyan
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>
2009-09-22const: mark remaining address_space_operations constAlexey Dobriyan
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>
2009-06-24switch nilfs2 to inode->i_aclAl Viro
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>
2009-06-10nilfs2: use device's backing_dev_info for btree node cachesRyusuke Konishi
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>
2009-05-11nilfs2: fix lock order reversal in nilfs_clean_segments ioctlRyusuke Konishi
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>
2009-04-13nilfs2: remove module versionRyusuke Konishi
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>
2009-04-07nilfs2: support nanosecond timestampRyusuke Konishi
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>
2009-04-07nilfs2: introduce secondary super blockRyusuke Konishi
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>
2009-04-07nilfs2: replace BUG_ON and BUG calls triggerable from ioctlRyusuke Konishi
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>
2009-04-07nilfs2: use unlocked_ioctlRyusuke Konishi
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>
2009-04-07nilfs2: remove compat ioctl codeRyusuke Konishi
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>