lwn.git/fs/reiserfs/bitmap.c, branch staging/v2.6.35

Merge branch 'for-next' into for-linus

2010-03-08T15:55:37+00:00

Conflicts: Documentation/filesystems/proc.txt arch/arm/mach-u300/include/mach/debug-macro.S drivers/net/qlge/qlge_ethtool.c drivers/net/qlge/qlge_main.c drivers/net/typhoon.c

dquot: cleanup space allocation / freeing routines

2010-03-04T23:20:28+00:00

Get rid of the alloc_space, free_space, reserve_space, claim_space and release_rsv dquot operations - they are always called from the filesystem and if a filesystem really needs their own (which none currently does) it can just call into it's own routine directly. Move shared logic into the common __dquot_alloc_space, dquot_claim_space_nodirty and __dquot_free_space low-level methods, and rationalize the wrappers around it to move as much as possible code into the common block for CONFIG_QUOTA vs not. Also rename all these helpers to be named dquot_* instead of vfs_dq_*. Signed-off-by: Christoph Hellwig Signed-off-by: Jan Kara

tree-wide: Assorted spelling fixes

2010-02-09T10:13:56+00:00

In particular, several occurances of funny versions of 'success', 'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address', 'beginning', 'desirable', 'separate' and 'necessary' are fixed. Signed-off-by: Daniel Mack Cc: Joe Perches Cc: Junio C Hamano Signed-off-by: Jiri Kosina

reiserfs: Fix possible recursive lock

2009-12-14T10:43:09+00:00

While allocating the bitmap using vmalloc, we hold the reiserfs lock, which makes lockdep later reporting a possible deadlock as we may swap out pages to allocate memory and then take the reiserfs lock recursively: inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage. kswapd0/312 [HC0[0]:SC0[0]:HE1:SE1] takes: (&REISERFS_SB(s)->lock){+.+.?.}, at: [] reiserfs_write_lock+0x28/0x40 {RECLAIM_FS-ON-W} state was registered at: [] mark_held_locks+0x62/0x90 [] lockdep_trace_alloc+0x9a/0xc0 [] kmem_cache_alloc+0x26/0xf0 [] __get_vm_area_node+0x6c/0xf0 [] __vmalloc_node+0x7e/0xa0 [] vmalloc+0x2b/0x30 [] reiserfs_init_bitmap_cache+0x39/0x70 [] reiserfs_fill_super+0x2e8/0xb90 [] get_sb_bdev+0x145/0x180 [] get_super_block+0x21/0x30 [] vfs_kern_mount+0x40/0xd0 [] do_kern_mount+0x39/0xd0 [] do_mount+0x2c7/0x6b0 [] sys_mount+0x66/0xa0 [] mount_block_root+0xc4/0x245 [] mount_root+0x59/0x5f [] prepare_namespace+0x111/0x14b [] kernel_init+0xcf/0xdb [] kernel_thread_helper+0x7/0x1c This is actually fine for two reasons: we call vmalloc at mount time then it's not in the swapping out path. Also the reiserfs lock can be acquired recursively, but since its implementation depends on a mutex, it's hard and not necessary worth it to teach that to lockdep. The lock is useless at mount time anyway, at least until we replay the journal. But let's remove it from this path later as this needs more thinking and is a sensible change. For now we can just relax the lock around vmalloc, Reported-by: Alexander Beregalov Signed-off-by: Frederic Weisbecker Cc: Chris Mason Cc: Ingo Molnar Cc: Thomas Gleixner

kill-the-BKL/reiserfs: release the write lock inside reiserfs_read_bitmap_block()

2009-09-14T05:18:11+00:00

reiserfs_read_bitmap_block() uses sb_bread() to read the bitmap block. This helper might sleep. Then, when the bkl was used, it was released at this point. We can then relax the write lock too here. [ Impact: release the reiserfs write lock when it is not needed ] Cc: Jeff Mahoney Cc: Chris Mason Cc: Alexander Beregalov Signed-off-by: Frederic Weisbecker

reiserfs: kill-the-BKL

2009-09-14T05:17:59+00:00

This patch is an attempt to remove the Bkl based locking scheme from reiserfs and is intended. It is a bit inspired from an old attempt by Peter Zijlstra: http://lkml.indiana.edu/hypermail/linux/kernel/0704.2/2174.html The bkl is heavily used in this filesystem to prevent from concurrent write accesses on the filesystem. Reiserfs makes a deep use of the specific properties of the Bkl: - It can be acqquired recursively by a same task - It is released on the schedule() calls and reacquired when schedule() returns The two properties above are a roadmap for the reiserfs write locking so it's very hard to simply replace it with a common mutex. - We need a recursive-able locking unless we want to restructure several blocks of the code. - We need to identify the sites where the bkl was implictly relaxed (schedule, wait, sync, etc...) so that we can in turn release and reacquire our new lock explicitly. Such implicit releases of the lock are often required to let other resources producer/consumer do their job or we can suffer unexpected starvations or deadlocks. So the new lock that replaces the bkl here is a per superblock mutex with a specific property: it can be acquired recursively by a same task, like the bkl. For such purpose, we integrate a lock owner and a lock depth field on the superblock information structure. The first axis on this patch is to turn reiserfs_write_(un)lock() function into a wrapper to manage this mutex. Also some explicit calls to lock_kernel() have been converted to reiserfs_write_lock() helpers. The second axis is to find the important blocking sites (schedule...(), wait_on_buffer(), sync_dirty_buffer(), etc...) and then apply an explicit release of the write lock on these locations before blocking. Then we can safely wait for those who can give us resources or those who need some. Typically this is a fight between the current writer, the reiserfs workqueue (aka the async commiter) and the pdflush threads. The third axis is a consequence of the second. The write lock is usually on top of a lock dependency chain which can include the journal lock, the flush lock or the commit lock. So it's dangerous to release and trying to reacquire the write lock while we still hold other locks. This is fine with the bkl: T1 T2 lock_kernel() mutex_lock(A) unlock_kernel() // do something lock_kernel() mutex_lock(A) -> already locked by T1 schedule() (and then unlock_kernel()) lock_kernel() mutex_unlock(A) .... This is not fine with a mutex: T1 T2 mutex_lock(write) mutex_lock(A) mutex_unlock(write) // do something mutex_lock(write) mutex_lock(A) -> already locked by T1 schedule() mutex_lock(write) -> already locked by T2 deadlock The solution in this patch is to provide a helper which releases the write lock and sleep a bit if we can't lock a mutex that depend on it. It's another simulation of the bkl behaviour. The last axis is to locate the fs callbacks that are called with the bkl held, according to Documentation/filesystem/Locking. Those are: - reiserfs_remount - reiserfs_fill_super - reiserfs_put_super Reiserfs didn't need to explicitly lock because of the context of these callbacks. But now we must take care of that with the new locking. After this patch, reiserfs suffers from a slight performance regression (for now). On UP, a high volume write with dd reports an average of 27 MB/s instead of 30 MB/s without the patch applied. Signed-off-by: Frederic Weisbecker Reviewed-by: Ingo Molnar Cc: Jeff Mahoney Cc: Peter Zijlstra Cc: Bron Gondwana Cc: Andrew Morton Cc: Linus Torvalds Cc: Alexander Viro LKML-Reference: <1239070789-13354-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar

Merge branch 'reiserfs-updates' from Jeff Mahoney

2009-03-30T19:33:01+00:00

* reiserfs-updates: (35 commits) reiserfs: rename [cn]_* variables reiserfs: rename p_._ variables reiserfs: rename p_s_tb to tb reiserfs: rename p_s_inode to inode reiserfs: rename p_s_bh to bh reiserfs: rename p_s_sb to sb reiserfs: strip trailing whitespace reiserfs: cleanup path functions reiserfs: factor out buffer_info initialization reiserfs: add atomic addition of selinux attributes during inode creation reiserfs: use generic readdir for operations across all xattrs reiserfs: journaled xattrs reiserfs: use generic xattr handlers reiserfs: remove i_has_xattr_dir reiserfs: make per-inode xattr locking more fine grained reiserfs: eliminate per-super xattr lock reiserfs: simplify xattr internal file lookups/opens reiserfs: Clean up xattrs when REISERFS_FS_XATTR is unset reiserfs: remove IS_PRIVATE helpers reiserfs: remove link detection code ... Fixed up conflicts manually due to: - quota name cleanups vs variable naming changes: fs/reiserfs/inode.c fs/reiserfs/namei.c fs/reiserfs/stree.c fs/reiserfs/xattr.c - exported include header cleanups include/linux/reiserfs_fs.h

reiserfs: use reiserfs_error()

2009-03-30T19:16:37+00:00

This patch makes many paths that are currently using warnings to handle the error. Signed-off-by: Jeff Mahoney Signed-off-by: Linus Torvalds

reiserfs: rework reiserfs_warning

2009-03-30T19:16:36+00:00

ReiserFS warnings can be somewhat inconsistent. In some cases: * a unique identifier may be associated with it * the function name may be included * the device may be printed separately This patch aims to make warnings more consistent. reiserfs_warning() prints the device name, so printing it a second time is not required. The function name for a warning is always helpful in debugging, so it is now automatically inserted into the output. Hans has stated that every warning should have a unique identifier. Some cases lack them, others really shouldn't have them. reiserfs_warning() now expects an id associated with each message. In the rare case where one isn't needed, "" will suffice. Signed-off-by: Jeff Mahoney Signed-off-by: Linus Torvalds

reiserfs: make some warnings informational

2009-03-30T19:16:35+00:00

In several places, reiserfs_warning is used when there is no warning, just a notice. This patch changes some of them to indicate that the message is merely informational. Signed-off-by: Jeff Mahoney Signed-off-by: Linus Torvalds