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2012-07-22fs/ufs: get rid of write_superArtem Bityutskiy
This patch makes UFS stop using the VFS '->write_super()' method along with the 's_dirt' superblock flag, because they are on their way out. The way we implement this is that we schedule a delay job instead relying on 's_dirt' and '->write_super()'. The whole "superblock write-out" VFS infrastructure is served by the 'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and writes out all dirty superblocks using the '->write_super()' call-back. But the problem with this thread is that it wastes power by waking up the system every 5 seconds, even if there are no diry superblocks, or there are no client file-systems which would need this (e.g., btrfs does not use '->write_super()'). So we want to kill it completely and thus, we need to make file-systems to stop using the '->write_super()' VFS service, and then remove it together with the kernel thread. Tested using fsstress from the LTP project. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-22fs/ufs: re-arrange the code a bitArtem Bityutskiy
This patch does not do any functional changes. It only moves 3 functions in fs/ufs/super.c a little bit up in order to prepare for further changes where I'll need this new arrangement to avoid forward declarations. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-22fs/ufs: remove extra superblock write on unmountArtem Bityutskiy
UFS calls 'ufs_write_super()' from 'ufs_put_super()' in order to write the superblocks to the media. However, it is not needed because VFS calls '->sync_fs()' before calling '->put_super()' - so by the time we are in 'ufs_write_super()', the superblocks are already synchronized. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14don't pass nameidata to ->create()Al Viro
boolean "does it have to be exclusive?" flag is passed instead; Local filesystem should just ignore it - the object is guaranteed not to be there yet. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14stop passing nameidata to ->lookup()Al Viro
Just the flags; only NFS cares even about that, but there are legitimate uses for such argument. And getting rid of that completely would require splitting ->lookup() into a couple of methods (at least), so let's leave that alone for now... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-28Merge tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linuxLinus Torvalds
Pull writeback tree from Wu Fengguang: "Mainly from Jan Kara to avoid iput() in the flusher threads." * tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Avoid iput() from flusher thread vfs: Rename end_writeback() to clear_inode() vfs: Move waiting for inode writeback from end_writeback() to evict_inode() writeback: Refactor writeback_single_inode() writeback: Remove wb->list_lock from writeback_single_inode() writeback: Separate inode requeueing after writeback writeback: Move I_DIRTY_PAGES handling writeback: Move requeueing when I_SYNC set to writeback_sb_inodes() writeback: Move clearing of I_SYNC into inode_sync_complete() writeback: initialize global_dirty_limit fs: remove 8 bytes of padding from struct writeback_control on 64 bit builds mm: page-writeback.c: local functions should not be exposed globally
2012-05-10vfs: make it possible to access the dentry hash/len as one 64-bit entryLinus Torvalds
This allows comparing hash and len in one operation on 64-bit architectures. Right now only __d_lookup_rcu() takes advantage of this, since that is the case we care most about. The use of anonymous struct/unions hides the alternate 64-bit approach from most users, the exception being a few cases where we initialize a 'struct qstr' with a static initializer. This makes the problematic cases use a new QSTR_INIT() helper function for that (but initializing just the name pointer with a "{ .name = xyzzy }" initializer remains valid, as does just copying another qstr structure). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-06vfs: Rename end_writeback() to clear_inode()Jan Kara
After we moved inode_sync_wait() from end_writeback() it doesn't make sense to call the function end_writeback() anymore. Rename it to clear_inode() which well says what the function really does - set I_CLEAR flag. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
2012-03-28Remove all #inclusions of asm/system.hDavid Howells
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-20switch open-coded instances of d_make_root() to new helperAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20vfs: check i_nlink limits in vfs_{mkdir,rename_dir,link}Al Viro
New field of struct super_block - ->s_max_links. Maximal allowed value of ->i_nlink or 0; in the latter case all checks still need to be done in ->link/->mkdir/->rename instances. Note that this limit applies both to directoris and to non-directories. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-06vfs: switch ->show_options() to struct dentry *Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03ufs: propagate umode_tAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03switch ->mknod() to umode_tAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03switch ->create() to umode_tAl Viro
vfs_create() ignores everything outside of 16bit subset of its mode argument; switching it to umode_t is obviously equivalent and it's the only caller of the method Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03switch vfs_mkdir() and ->mkdir() to umode_tAl Viro
vfs_mkdir() gets int, but immediately drops everything that might not fit into umode_t and that's the only caller of ->mkdir()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: fix the stupidity with i_dentry in inode destructorsAl Viro
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once(); the cost of taking it into inode_init_always() will be negligible for pipes and sockets and negative for everything else. Not to mention the removal of boilerplate code from ->destroy_inode() instances... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-11-02filesystems: add set_nlink()Miklos Szeredi
Replace remaining direct i_nlink updates with a new set_nlink() updater function. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-11-02filesystems: add missing nlink wrappersMiklos Szeredi
Replace direct i_nlink updates with the respective updater function (inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-10-31treewide: 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>
2011-07-20make d_splice_alias(ERR_PTR(err), dentry) = ERR_PTR(err)Al Viro
... and simplify the living hell out of callers Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-17ufs should use d_splice_alias()Al Viro
it's NFS-exportable, so... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-28ufs: remove unnecessary dentry_unhash from rmdir, dir renameSage Weil
ufs does not have problems with references to unlinked directories. CC: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-26ufs: fix truncated values handling 64 bit metadataDan Carpenter
Originally i_lastfrag was 32 bits but then we added support for handling 64 bit metadata and it became a 64 bit variable. That was during 2007, in 54fb996ac15c "[PATCH] ufs2 write: block allocation update". Unfortunately these casts got left behind so the value got truncated to 32 bit again. [akpm@linux-foundation.org: remove now-unneeded min_t/max_t casting] Signed-off-by: Dan Carpenter <error27@gmail.com> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26Merge 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: (25 commits) cifs: remove unnecessary dentry_unhash on rmdir/rename_dir ocfs2: remove unnecessary dentry_unhash on rmdir/rename_dir exofs: remove unnecessary dentry_unhash on rmdir/rename_dir nfs: remove unnecessary dentry_unhash on rmdir/rename_dir ext2: remove unnecessary dentry_unhash on rmdir/rename_dir ext3: remove unnecessary dentry_unhash on rmdir/rename_dir ext4: remove unnecessary dentry_unhash on rmdir/rename_dir btrfs: remove unnecessary dentry_unhash in rmdir/rename_dir ceph: remove unnecessary dentry_unhash calls vfs: clean up vfs_rename_other vfs: clean up vfs_rename_dir vfs: clean up vfs_rmdir vfs: fix vfs_rename_dir for FS_RENAME_DOES_D_MOVE filesystems libfs: drop unneeded dentry_unhash vfs: update dentry_unhash() comment vfs: push dentry_unhash on rename_dir into file systems vfs: push dentry_unhash on rmdir into file systems vfs: remove dget() from dentry_unhash() vfs: dentry_unhash immediately prior to rmdir vfs: Block mmapped writes while the fs is frozen ...
2011-05-26vfs: push dentry_unhash on rename_dir into file systemsSage Weil
Only a few file systems need this. Start by pushing it down into each rename method (except gfs2 and xfs) so that it can be dealt with on a per-fs basis. Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-26vfs: push dentry_unhash on rmdir into file systemsSage Weil
Only a few file systems need this. Start by pushing it down into each fs rmdir method (except gfs2 and xfs) so it can be dealt with on a per-fs basis. This does not change behavior for any in-tree file systems. Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-04-26Merge branch 'master' into for-nextJiri Kosina
Fast-forwarded to current state of Linus' tree as there are patches to be applied for files that didn't exist on the old branch.
2011-04-08ufs: Fix a typoAlessio Igor Bogani
Signed-off-by: Alessio Igor Bogani <abogani@kernel.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-04-07Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6Linus Torvalds
* 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6: Fix common misspellings
2011-04-05ufs: remove unessecary blk_flush_plugChristoph Hellwig
We already flush the per-process plugging list when context switching, so a blk_flush_plug call just before a yield() is not needed. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-24Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits) Documentation/iostats.txt: bit-size reference etc. cfq-iosched: removing unnecessary think time checking cfq-iosched: Don't clear queue stats when preempt. blk-throttle: Reset group slice when limits are changed blk-cgroup: Only give unaccounted_time under debug cfq-iosched: Don't set active queue in preempt block: fix non-atomic access to genhd inflight structures block: attempt to merge with existing requests on plug flush block: NULL dereference on error path in __blkdev_get() cfq-iosched: Don't update group weights when on service tree fs: assign sb->s_bdi to default_backing_dev_info if the bdi is going away block: Require subsystems to explicitly allocate bio_set integrity mempool jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging fs: make fsync_buffers_list() plug mm: make generic_writepages() use plugging blk-cgroup: Add unaccounted time to timeslice_used. block: fixup plugging stubs for !CONFIG_BLOCK block: remove obsolete comments for blkdev_issue_zeroout. blktrace: Use rq->cmd_flags directly in blk_add_trace_rq. ... Fix up conflicts in fs/{aio.c,super.c}
2011-03-23ufs: use little-endian bitopsAkinobu Mita
As a preparation for removing ext2 non-atomic bit operations from asm/bitops.h. This converts ext2 non-atomic bit operations to little-endian bit operations. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-16Merge branch 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bklLinus Torvalds
* 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl: BKL: That's all, folks fs/locks.c: Remove stale FIXME left over from BKL conversion ipx: remove the BKL appletalk: remove the BKL x25: remove the BKL ufs: remove the BKL hpfs: remove the BKL drivers: remove extraneous includes of smp_lock.h tracing: don't trace the BKL adfs: remove the big kernel lock
2011-03-10block: remove per-queue pluggingJens Axboe
Code has been converted over to the new explicit on-stack plugging, and delay users have been converted to use the new API for that. So lets kill off the old plugging along with aops->sync_page(). Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-03ufs: i_nlink races in rename()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-02ufs: remove the BKLArnd Bergmann
This introduces a new per-superblock mutex in UFS to replace the big kernel lock. I have been careful to avoid nested calls to lock_ufs and to get the lock order right with respect to other mutexes, in particular lock_super. I did not make any attempt to prove that the big kernel lock is not needed in a particular place in the code, which is very possible. The mutex has a significant performance impact, so it is only used on SMP or PREEMPT configurations. As Nick Piggin noticed, any allocation inside of the lock may end up deadlocking when we get to ufs_getfrag_block in the reclaim task, so we now use GFP_NOFS. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Nick Bowler <nbowler@elliptictech.com> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: Nick Piggin <npiggin@gmail.com>
2011-01-07fs: icache RCU free inodesNick Piggin
RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2010-10-29new helper: mount_bdev()Al Viro
... and switch of the obvious get_sb_bdev() users to ->mount() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25new helper: ihold()Al Viro
Clones an existing reference to inode; caller must already hold one. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-22Merge branch 'vfs' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bklLinus Torvalds
* 'vfs' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl: (30 commits) BKL: remove BKL from freevxfs BKL: remove BKL from qnx4 autofs4: Only declare function when CONFIG_COMPAT is defined autofs: Only declare function when CONFIG_COMPAT is defined ncpfs: Lock socket in ncpfs while setting its callbacks fs/locks.c: prepare for BKL removal BKL: Remove BKL from ncpfs BKL: Remove BKL from OCFS2 BKL: Remove BKL from squashfs BKL: Remove BKL from jffs2 BKL: Remove BKL from ecryptfs BKL: Remove BKL from afs BKL: Remove BKL from USB gadgetfs BKL: Remove BKL from autofs4 BKL: Remove BKL from isofs BKL: Remove BKL from fat BKL: Remove BKL from ext2 filesystem BKL: Remove BKL from do_new_mount() BKL: Remove BKL from cgroup BKL: Remove BKL from NTFS ...
2010-10-21BKL: introduce CONFIG_BKL.Arnd Bergmann
With all the patches we have queued in the BKL removal tree, only a few dozen modules are left that actually rely on the BKL, and even there are lots of low-hanging fruit. We need to decide what to do about them, this patch illustrates one of the options: Every user of the BKL is marked as 'depends on BKL' in Kconfig, and the CONFIG_BKL becomes a user-visible option. If it gets disabled, no BKL using module can be built any more and the BKL code itself is compiled out. The one exception is file locking, which is practically always enabled and does a 'select BKL' instead. This effectively forces CONFIG_BKL to be enabled until we have solved the fs/lockd mess and can apply the patch that removes the BKL from fs/locks.c. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-10-04BKL: Explicitly add BKL around get_sb/fill_superJan Blunck
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>
2010-08-18remove SWRITE* I/O typesChristoph Hellwig
These flags aren't real I/O types, but tell ll_rw_block to always lock the buffer instead of giving up on a failed trylock. Instead add a new write_dirty_buffer helper that implements this semantic and use it from the existing SWRITE* callers. Note that the ll_rw_block code had a bug where it didn't promote WRITE_SYNC_PLUG properly, which this patch fixes. In the ufs code clean up the helper that used to call ll_rw_block to mirror sync_dirty_buffer, which is the function it implements for compound buffers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09switch ufs to ->evict_inode()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09check ATTR_SIZE contraints in inode_change_okChristoph Hellwig
Make sure we check the truncate constraints early on in ->setattr by adding those checks to inode_change_ok. Also clean up and document inode_change_ok to make this obvious. As a fallout we don't have to call inode_newsize_ok from simple_setsize and simplify it down to a truncate_setsize which doesn't return an error. This simplifies a lot of setattr implementations and means we use truncate_setsize almost everywhere. Get rid of fat_setsize now that it's trivial and mark ext2_setsize static to make the calling convention obvious. Keep the inode_newsize_ok in vmtruncate for now as all callers need an audit for its removal anyway. Note: setattr code in ecryptfs doesn't call inode_change_ok at all and needs a deeper audit, but that is left for later. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09remove inode_setattrChristoph Hellwig
Replace inode_setattr with opencoded variants of it in all callers. This moves the remaining call to vmtruncate into the filesystem methods where it can be replaced with the proper truncate sequence. In a few cases it was obvious that we would never end up calling vmtruncate so it was left out in the opencoded variant: spufs: explicitly checks for ATTR_SIZE earlier btrfs,hugetlbfs,logfs,dlmfs: explicitly clears ATTR_SIZE earlier ufs: contains an opencoded simple_seattr + truncate that sets the filesize just above In addition to that ncpfs called inode_setattr with handcrafted iattrs, which allowed to trim down the opencoded variant. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09get rid of block_write_begin_newtruncChristoph Hellwig
Move the call to vmtruncate to get rid of accessive blocks to the callers in preparation of the new truncate sequence and rename the non-truncating version to block_write_begin. While we're at it also remove several unused arguments to block_write_begin. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09introduce __block_write_beginChristoph Hellwig
Split up the block_write_begin implementation - __block_write_begin is a new trivial wrapper for block_prepare_write that always takes an already allocated page and can be either called from block_write_begin or filesystem code that already has a page allocated. Remove the handling of already allocated pages from block_write_begin after switching all callers that do it to __block_write_begin. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>