Commit Graph

54 Commits

Author SHA1 Message Date
Jens Axboe b31dc66a54 [PATCH] Kill PF_SYNCWRITE flag
A process flag to indicate whether we are doing sync io is incredibly
ugly. It also causes performance problems when one does a lot of async
io and then proceeds to sync it. Part of the io will go out as async,
and the other part as sync. This causes a disconnect between the
previously submitted io and the synced io. For io schedulers such as CFQ,
this will cause us lost merges and suboptimal behaviour in scheduling.

Remove PF_SYNCWRITE completely from the fsync/msync paths, and let
the O_DIRECT path just directly indicate that the writes are sync
by using WRITE_SYNC instead.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-06-23 17:10:39 +02:00
KAMEZAWA Hiroyuki ec936fc563 [PATCH] for_each_online_pgdat: renaming for_each_pgdat
Replace for_each_pgdat() with for_each_online_pgdat().

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:48 -08:00
Linus Torvalds 9ae21d1bb3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  drivers/char/ftape/lowlevel/fdc-io.c: Correct a comment
  Kconfig help: MTD_JEDECPROBE already supports Intel
  Remove ugly debugging stuff
  do_mounts.c: Minor ROOT_DEV comment cleanup
  BUG_ON() Conversion in drivers/s390/block/dasd_devmap.c
  BUG_ON() Conversion in mm/mempool.c
  BUG_ON() Conversion in mm/memory.c
  BUG_ON() Conversion in kernel/fork.c
  BUG_ON() Conversion in ipc/sem.c
  BUG_ON() Conversion in fs/ext2/
  BUG_ON() Conversion in fs/hfs/
  BUG_ON() Conversion in fs/dcache.c
  BUG_ON() Conversion in fs/buffer.c
  BUG_ON() Conversion in input/serio/hp_sdc_mlc.c
  BUG_ON() Conversion in md/dm-table.c
  BUG_ON() Conversion in md/dm-path-selector.c
  BUG_ON() Conversion in drivers/isdn
  BUG_ON() Conversion in drivers/char
  BUG_ON() Conversion in drivers/mtd/
2006-03-26 09:41:18 -08:00
Badari Pulavarty b0cf2321c6 [PATCH] pass b_size to ->get_block()
Pass amount of disk needs to be mapped to get_block().  This way one can
modify the fs ->get_block() functions to map multiple blocks at the same time.

[akpm@osdl.org: performance tweak]
[akpm@osdl.org: remove unneeded assignments]
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:01 -08:00
Badari Pulavarty 205f87f6b3 [PATCH] change buffer_head.b_size to size_t
Increase the size of the buffer_head b_size field (only) for 64 bit platforms.
Update some old and moldy comments in and around the structure as well.

The b_size increase allows us to perform larger mappings and allocations for
large I/O requests from userspace, which tie in with other changes allowing
the get_block_t() interface to map multiple blocks at once.

Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:01 -08:00
NeilBrown 2ff28e22bd [PATCH] Make address_space_operations->invalidatepage return void
The return value of this function is never used, so let's be honest and
declare it as void.

Some places where invalidatepage returned 0, I have inserted comments
suggesting a BUG_ON.

[akpm@osdl.org: JBD BUG fix]
[akpm@osdl.org: rework for git-nfs]
[akpm@osdl.org: don't go BUG in block_invalidate_page()]
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:55 -08:00
NeilBrown 3978d7179d [PATCH] Make address_space_operations->sync_page return void
The only user ignores the return value, and the only instanace
(block_sync_page) always returns 0...

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:55 -08:00
Eric Sesterhenn e827f92355 BUG_ON() Conversion in fs/buffer.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-26 18:24:46 +02:00
OGAWA Hirofumi d25b9a1ff0 [PATCH] freeze_bdev() cleanup
freeze_bdev() uses a fsync_super() without sync_blockdev().  This patch
makes __fsync_super() and shares it.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:56 -08:00
Andrew Morton 18e79b40ed [PATCH] fsync: extract internal code
Pull the guts out of do_fsync() - we can use it elsewhere.

Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:27 -08:00
Andrew Morton 4741c9fd36 [PATCH] set_page_dirty() return value fixes
We need set_page_dirty() to return true if it actually transitioned the page
from a clean to dirty state.  This wasn't right in a couple of places.  Do a
kernel-wide audit, fix things up.

This leaves open the possibility of returning a negative errno from
set_page_dirty() sometime in the future.  But we don't do that at present.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:26 -08:00
Eric Dumazet 8a14342683 [PATCH] HOTPLUG_CPU: avoid hitting too many cachelines in recalc_bh_state()
Instead of using for_each_cpu(i), we can use for_each_online_cpu(i).

When a CPU goes offline (ie removed from online map), it might have a non
null bh_accounting.nr, so this patch adds a transfer of this counter to an
online CPU counter.

We already have a hotcpu_notifier, (function buffer_cpu_notify()), where we
can do this bh_accounting.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:26 -08:00
Paul Jackson b0196009d8 [PATCH] cpuset memory spread slab cache hooks
Change the kmem_cache_create calls for certain slab caches to support cpuset
memory spreading.

See the previous patches, cpuset_mem_spread, for an explanation of cpuset
memory spreading, and cpuset_mem_spread_slab_cache for the slab cache support
for memory spreading.

The slab caches marked for now are: dentry_cache, inode_cache, some xfs slab
caches, and buffer_head.  This list may change over time.  In particular,
other file system types that are used extensively on large NUMA systems may
want to allow for spreading their directory and inode slab cache entries.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:23 -08:00
Arjan van de Ven c039e3134a [PATCH] sem2mutex: blockdev #2
Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:11 -08:00
Christoph Lameter b20a35035f [PATCH] page migration reorg
Centralize the page migration functions in anticipation of additional
tinkering.  Creates a new file mm/migrate.c

1. Extract buffer_migrate_page() from fs/buffer.c

2. Extract central migration code from vmscan.c

3. Extract some components from mempolicy.c

4. Export pageout() and remove_from_swap() from vmscan.c

5. Make it possible to configure NUMA systems without page migration
   and non-NUMA systems with page migration.

I had to so some #ifdeffing in mempolicy.c that may need a cleanup.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:06 -08:00
Christoph Lameter 4983da07f1 [PATCH] page migration: fail if page is in a vma flagged VM_LOCKED
page migration currently simply retries a couple of times if try_to_unmap()
fails without inspecting the return code.

However, SWAP_FAIL indicates that the page is in a vma that has the
VM_LOCKED flag set (if ignore_refs ==1).  We can check for that return code
and avoid retrying the migration.

migrate_page_remove_references() now needs to return a reason why the
failure occured.  So switch migrate_page_remove_references to use -Exx
style error messages.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-14 21:43:02 -08:00
OGAWA Hirofumi e60e5c50aa [PATCH] Trivial optimization of ll_rw_block()
The ll_rw_block() needs to get ref-count only if it submits a buffer().  This
patch avoids the needless get/put of ref-count.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:32:10 -08:00
Chris Mason fc5cd582e9 [PATCH] reiserfs: zero b_private when allocating buffer heads
The b_private field in buffer heads needs to be zero filled when the
buffers are allocated.  Thanks to Nathan Scott for finding this.  It was
causing problems on systems with both XFS and reiserfs.

Signed-off-by: Chris Mason <mason@suse.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:26 -08:00
Christoph Lameter e965f9630c [PATCH] Direct Migration V9: Avoid writeback / page_migrate() method
Migrate a page with buffers without requiring writeback

This introduces a new address space operation migratepage() that may be used
by a filesystem to implement its own version of page migration.

A version is provided that migrates buffers attached to pages.  Some
filesystems (ext2, ext3, xfs) are modified to utilize this feature.

The swapper address space operation are modified so that a regular
migrate_page() will occur for anonymous pages without writeback (migrate_pages
forces every anonymous page to have a swap entry).

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:17 -08:00
Nathan Scott 01ffe339e3 Make alloc_page_buffers() initialise buffer_heads using init_buffer(),
like other routines here, to ensure buffers are correctly initialised
with respect to b_private/b_end_io.  Fixes an odd interaction between
XFS and reiserfs.

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-01-17 09:02:07 +11:00
Arjan van de Ven 858119e159 [PATCH] Unlinline a bunch of other functions
Remove the "inline" keyword from a bunch of big functions in the kernel with
the goal of shrinking it by 30kb to 40kb

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:06 -08:00
Randy Dunlap 16f7e0fe2e [PATCH] capable/capability.h (fs/)
fs: Use <linux/capability.h> where capable() is used.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:13 -08:00
Jes Sorensen 1b1dcc1b57 [PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-09 15:59:24 -08:00
Andrew Morton 54b21a7992 [PATCH] fix possible PAGE_CACHE_SHIFT overflows
We've had two instances recently of overflows when doing

	64_bit_value = (32_bit_value << PAGE_CACHE_SHIFT)

I did a tree-wide grep of `<<.*PAGE_CACHE_SHIFT' and this is the result.

- afs_rxfs_fetch_descriptor.offset is of type off_t, which seems broken.

- jfs and jffs are limited to 4GB anyway.

- reiserfs map_block_for_writepage() takes an unsigned long for the block -
  it should take sector_t.  (It'll fail for huge filesystems with
  blocksize<PAGE_CACHE_SIZE)

- cramfs_read() needs to use sector_t (I think cramsfs is busted on large
  filesystems anyway)

- affs is limited in file size anyway.

- I generally didn't fix 32-bit overflows in directory operations.

- arm's __flush_dcache_page() is peculiar.  What if the page lies beyond 4G?

- gss_wrap_req_priv() needs checking (snd_buf->page_base)

Cc: Oleg Drokin <green@linuxhacker.ru>
Cc: David Howells <dhowells@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: <reiserfs-dev@namesys.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:54 -08:00
OGAWA Hirofumi 28fd129827 [PATCH] Fix and add EXPORT_SYMBOL(filemap_write_and_wait)
This patch add EXPORT_SYMBOL(filemap_write_and_wait) and use it.

See mm/filemap.c:

And changes the filemap_write_and_wait() and filemap_write_and_wait_range().

Current filemap_write_and_wait() doesn't wait if filemap_fdatawrite()
returns error.  However, even if filemap_fdatawrite() returned an
error, it may have submitted the partially data pages to the device.
(e.g. in the case of -ENOSPC)

<quotation>
Andrew Morton writes,

If filemap_fdatawrite() returns an error, this might be due to some
I/O problem: dead disk, unplugged cable, etc.  Given the generally
crappy quality of the kernel's handling of such exceptions, there's a
good chance that the filemap_fdatawait() will get stuck in D state
forever.
</quotation>

So, this patch doesn't wait if filemap_fdatawrite() returns the -EIO.

Trond, could you please review the nfs part?  Especially I'm not sure,
nfs must use the "filemap_fdatawrite(inode->i_mapping) == 0", or not.

Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:47 -08:00
OGAWA Hirofumi 05eb0b51fb [PATCH] fat: support a truncate() for expanding size (generic_cont_expand)
This patch changes generic_cont_expand(), in order to share the code
with fatfs.

  - Use vmtruncate() if ->prepare_write() returns a error.

Even if ->prepare_write() returns an error, it may already have added some
blocks.  So, this truncates blocks outside of ->i_size by vmtruncate().

  - Add generic_cont_expand_simple().

The generic_cont_expand_simple() assumes that ->prepare_write() can handle
the block boundary.  With this, we don't need to care the extra byte.

And for expanding a file size by truncate(), fatfs uses the
added generic_cont_expand_simple().

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:47 -08:00
Coywolf Qi Hunt 385fd4c59d [PATCH] __find_get_block_slow() cleanup
Get rid of the `int unused' parameter of __find_get_block_slow().

Signed-off-by: Coywolf Qi Hunt <qiyong@fc-cn.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:39 -08:00
Andrew Morton a3e713b5fd [PATCH] __bread oops fix
If a filesystem passes an idiotic blocksize into bread(), __getblk_slow() will
warn and will return NULL.  We have a report (from Hubert Tonneau
<hubert.tonneau@fullpliant.org>) of isofs_fill_super() doing this (passing in
a silly block size) against an unplugged CDROM drive.

But a couple of __getblk_slow() callers forgot to check for the NULL bh, hence
oops.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:27 -08:00
Jan Kara aaa4059bc2 [PATCH] ext3: Fix unmapped buffers in transaction's lists
Fix the problem (BUG 4964) with unmapped buffers in transaction's
t_sync_data list.  The problem is we need to call filesystem's own
invalidatepage() from block_write_full_page().

block_write_full_page() must call filesystem's invalidatepage().  Otherwise
following nasty race can happen:

   proc 1                                        proc 2
   ------                                        ------
- write some new data to 'offset'
  => bh gets to the transactions data list
                                              - starts truncate
                                                => i_size set to new size
- mpage_writepages()
  - ext3_ordered_writepage() to 'offset'
    - block_write_full_page()
      - page->index > end_index+1
        - block_invalidatepage()
          - discard_buffer()
            - clear_buffer_mapped()

- commit triggers and finds unmapped buffer - BOOM!

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:17 -08:00
Hugh Dickins 4c21e2f244 [PATCH] mm: split page table lock
Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.

This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock.  (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)

In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.

Splitting the lock is not quite for free: another cacheline access.  Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS.  But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.

There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29 21:40:42 -07:00
Al Viro 27496a8c67 [PATCH] gfp_t: fs/*
- ->releasepage() annotated (s/int/gfp_t), instances updated
 - missing gfp_t in fs/* added
 - fixed misannotation from the original sweep caught by bitwise checks:
   XFS used __nocast both for gfp_t and for flags used by XFS allocator.
   The latter left with unsigned int __nocast; we might want to add a
   different type for those but for now let's leave them alone.  That,
   BTW, is a case when __nocast use had been actively confusing - it had
   been used in the same code for two different and similar types, with
   no way to catch misuses.  Switch of gfp_t to bitwise had caught that
   immediately...

One tricky bit is left alone to be dealt with later - mapping->flags is
a mix of gfp_t and error indications.  Left alone for now.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28 08:16:47 -07:00
Al Viro af4ca457ea [PATCH] gfp_t: infrastructure
Beginning of gfp_t annotations:

 - -Wbitwise added to CHECKFLAGS
 - old __bitwise renamed to __bitwise__
 - __bitwise defined to either __bitwise__ or nothing, depending on
   __CHECK_ENDIAN__ being defined
 - gfp_t switched from __nocast to __bitwise__
 - force cast to gfp_t added to __GFP_... constants
 - new helper - gfp_zone(); extracts zone bits out of gfp_t value and casts
   the result to int

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28 08:16:46 -07:00
Al Viro dd0fc66fb3 [PATCH] gfp flags annotations - part 1
- added typedef unsigned int __nocast gfp_t;

 - replaced __nocast uses for gfp flags with gfp_t - it gives exactly
   the same warnings as far as sparse is concerned, doesn't change
   generated code (from gcc point of view we replaced unsigned int with
   typedef) and documents what's going on far better.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-08 15:00:57 -07:00
Ingo Molnar fb1c8f93d8 [PATCH] spinlock consolidation
This patch (written by me and also containing many suggestions of Arjan van
de Ven) does a major cleanup of the spinlock code.  It does the following
things:

 - consolidates and enhances the spinlock/rwlock debugging code

 - simplifies the asm/spinlock.h files

 - encapsulates the raw spinlock type and moves generic spinlock
   features (such as ->break_lock) into the generic code.

 - cleans up the spinlock code hierarchy to get rid of the spaghetti.

Most notably there's now only a single variant of the debugging code,
located in lib/spinlock_debug.c.  (previously we had one SMP debugging
variant per architecture, plus a separate generic one for UP builds)

Also, i've enhanced the rwlock debugging facility, it will now track
write-owners.  There is new spinlock-owner/CPU-tracking on SMP builds too.
All locks have lockup detection now, which will work for both soft and hard
spin/rwlock lockups.

The arch-level include files now only contain the minimally necessary
subset of the spinlock code - all the rest that can be generalized now
lives in the generic headers:

 include/asm-i386/spinlock_types.h       |   16
 include/asm-x86_64/spinlock_types.h     |   16

I have also split up the various spinlock variants into separate files,
making it easier to see which does what. The new layout is:

   SMP                         |  UP
   ----------------------------|-----------------------------------
   asm/spinlock_types_smp.h    |  linux/spinlock_types_up.h
   linux/spinlock_types.h      |  linux/spinlock_types.h
   asm/spinlock_smp.h          |  linux/spinlock_up.h
   linux/spinlock_api_smp.h    |  linux/spinlock_api_up.h
   linux/spinlock.h            |  linux/spinlock.h

/*
 * here's the role of the various spinlock/rwlock related include files:
 *
 * on SMP builds:
 *
 *  asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
 *                        initializers
 *
 *  linux/spinlock_types.h:
 *                        defines the generic type and initializers
 *
 *  asm/spinlock.h:       contains the __raw_spin_*()/etc. lowlevel
 *                        implementations, mostly inline assembly code
 *
 *   (also included on UP-debug builds:)
 *
 *  linux/spinlock_api_smp.h:
 *                        contains the prototypes for the _spin_*() APIs.
 *
 *  linux/spinlock.h:     builds the final spin_*() APIs.
 *
 * on UP builds:
 *
 *  linux/spinlock_type_up.h:
 *                        contains the generic, simplified UP spinlock type.
 *                        (which is an empty structure on non-debug builds)
 *
 *  linux/spinlock_types.h:
 *                        defines the generic type and initializers
 *
 *  linux/spinlock_up.h:
 *                        contains the __raw_spin_*()/etc. version of UP
 *                        builds. (which are NOPs on non-debug, non-preempt
 *                        builds)
 *
 *   (included on UP-non-debug builds:)
 *
 *  linux/spinlock_api_up.h:
 *                        builds the _spin_*() APIs.
 *
 *  linux/spinlock.h:     builds the final spin_*() APIs.
 */

All SMP and UP architectures are converted by this patch.

arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
crosscompilers.  m32r, mips, sh, sparc, have not been tested yet, but should
be mostly fine.

From: Grant Grundler <grundler@parisc-linux.org>

  Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
  Builds 32-bit SMP kernel (not booted or tested).  I did not try to build
  non-SMP kernels.  That should be trivial to fix up later if necessary.

  I converted bit ops atomic_hash lock to raw_spinlock_t.  Doing so avoids
  some ugly nesting of linux/*.h and asm/*.h files.  Those particular locks
  are well tested and contained entirely inside arch specific code.  I do NOT
  expect any new issues to arise with them.

 If someone does ever need to use debug/metrics with them, then they will
  need to unravel this hairball between spinlocks, atomic ops, and bit ops
  that exist only because parisc has exactly one atomic instruction: LDCW
  (load and clear word).

From: "Luck, Tony" <tony.luck@intel.com>

   ia64 fix

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjanv@infradead.org>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 10:06:21 -07:00
Jan Kara a766223625 [PATCH] Make ll_rw_block() wait for buffer lock
Introduce new ll_rw_block() operation SWRITE meaning that block layer should
wait for the buffer lock and write-out afterwards.  Hence data in buffers at
the time of call are guaranteed to be submitted to the disk.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:55 -07:00
Coywolf Qi Hunt 736c7b808f [PATCH] alloc_buffer_head() and free_buffer_head() cleanup
Signed-off-by: Coywolf Qi Hunt <qiyong@fc-cn.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:41 -07:00
Nick Piggin a39722034a [PATCH] page_uptodate locking scalability
Use a bit spin lock in the first buffer of the page to synchronise asynch
IO buffer completions, instead of the global page_uptodate_lock, which is
showing some scalabilty problems.

Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-07 18:23:45 -07:00
Pekka J Enberg 687a21cee1 [PATCH] rename wakeup_bdflush to wakeup_pdflush
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 21:20:31 -07:00
Anton Altaparmakov 152becd26e [PATCH] Bug in error recovery in fs/buffer.c::__block_prepare_write()
fs/buffer.c::__block_prepare_write() has broken error recovery.  It calls
the get_block() callback with "create = 1" and if that succeeds it
immediately clears buffer_new on the just allocated buffer (which has
buffer_new set).

The bug is that if an error occurs and get_block() returns != 0, we break
from this loop and go into recovery code.  This code has this comment:

/* Error case: */
/*
 * Zero out any newly allocated blocks to avoid exposing stale
 * data.  If BH_New is set, we know that the block was newly
 * allocated in the above loop.
 */

So the intent is obviously good in that it wants to clear just allocated
and hence not zeroed buffers.  However the code recognises allocated
buffers by checking for buffer_new being set.

Unfortunately __block_prepare_write() as discussed above already cleared
buffer_new on all allocated buffers thus no buffers will be cleared during
error recovery and old data will be leaked.

The simplest way I can see to fix this is to make the current recovery code
work by _not_ clearing buffer_new after calling get_block() in
__block_prepare_write().

We cannot safely allow buffer_new buffers to "leak out" of
__block_prepare_write(), thus we simply do a quick loop over the buffers
clearing buffer_new on each of them if it is set just before returning
"success" from __block_prepare_write().

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:34 -07:00
Oleg Nesterov dfb388bf8a [PATCH] factor out common code in sys_fsync/sys_fdatasync
This patch consolidates sys_fsync and sys_fdatasync.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:29 -07:00
Darren Hart 1ad539b2bd [PATCH] vm: try_to_free_pages unused argument
try_to_free_pages accepts a third argument, order, but hasn't used it since
before 2.6.0.  The following patch removes the argument and updates all the
calls to try_to_free_pages.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:17 -07:00
Andrew Morton c64610ba58 [PATCH] block_read_full_page() get_block() error handling fix
If block_read_full_page() detects an error when running get_block() it will
run SetPageError(), then it will zero out the block in pagecache and will mark
the buffer_head uptodate.

So at the end of readahead we end up with a non-uptodate pagecache page which
is marked PageError.  But it has uptodate buffers.

The pagefault code will run ClearPageError, will launch readpage a second time
and block_read_full_page() will notice the uptodate buffers and will mark the
page uptodate as well.  We end up with an uptodate, !PageError page full of
zeros and the error is lost.

(It seems a little odd that filemap_nopage() runs ClearPageError().  I guess
all of this adds up to meaning that for each attempted access to the page, the
pagefault handler will retry the I/O.  Which is good and bad.  If the app is
ignoring SIGBUS for some reason we could get a lot of back-to-back I/O
errors.)

Fix it by not marking the pagecache buffer_head as uptodate if the attempt to
map that buffer to a disk block failed.

Credit-to: Qu Fuping <fs@ercist.iscas.ac.cn>

  For reporting the bug and identifying its source.

Signed-off-by: Qu Fuping <fs@ercist.iscas.ac.cn>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-17 07:59:20 -07:00
Adrian Bunk 75c96f8584 [PATCH] make some things static
This patch makes some needlessly global identifiers static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Arjan van de Ven <arjanv@infradead.org>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:47 -07:00
Andrew Morton f0fbd5fc09 [PATCH] __block_write_full_page() simplification
The `last_bh' logic probably isn't worth much.  In those situations where only
the front part of the page is being written out we will save some looping but
in the vastly more common case of an all-page writeout if just adds more code.

Nick Piggin <nickpiggin@yahoo.com.au>

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:41 -07:00
Andrew Morton 05937baae9 [PATCH] __block_write_full_page speedup
Remove all those get_bh()'s and put_bh()'s by extending lock_page() to cover
the troublesome regions.

(get_bh() and put_bh() happen every time whereas contention on a page's lock
in there happens basically never).

Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:41 -07:00
Nick Piggin ad576e63e0 [PATCH] __block_write_full_page race fix
When running
	fsstress -v -d $DIR/tmp -n 1000 -p 1000 -l 2
on an ext2 filesystem with 1024 byte block size, on SMP i386 with 4096 byte
page size over loopback to an image file on a tmpfs filesystem, I would
very quickly hit
	BUG_ON(!buffer_async_write(bh));
in fs/buffer.c:end_buffer_async_write

It seems that more than one request would be submitted for a given bh
at a time.

What would happen is the following:
2 threads doing __mpage_writepages on the same page.
Thread 1 - lock the page first, and enter __block_write_full_page.
Thread 1 - (eg.) mark_buffer_async_write on the first 2 buffers.
Thread 1 - set page writeback, unlock page.
Thread 2 - lock page, wait on page writeback
Thread 1 - submit_bh on the first 2 buffers.
=> both requests complete, none of the page buffers are async_write,
   end_page_writeback is called.
Thread 2 - wakes up. enters __block_write_full_page.
Thread 2 - mark_buffer_async_write on (eg.) the last buffer
Thread 1 - finds the last buffer has async_write set, submit_bh on that.
Thread 2 - submit_bh on the last buffer.
=> oops.

So change __block_write_full_page to explicitly keep track of the last bh
we need to issue, so we don't touch anything after issuing the last
request.

Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:40 -07:00
Nick Piggin f3ddbdc626 [PATCH] fix race in __block_prepare_write
Fix a race where __block_prepare_write can leak out an in-flight read
against a bh if get_block returns an error.  This can lead to the page
becoming unlocked while the buffer is locked and the read still in flight.
__mpage_writepage BUGs on this condition.

BUG sighted on a 2-way Itanium2 system with 16K PAGE_SIZE running

	fsstress -v -d $DIR/tmp -n 1000 -p 1000 -l 2

where $DIR is a new ext2 filesystem with 4K blocks that is quite
small (causing get_block to fail often with -ENOSPC).

Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:40 -07:00
Andrea Arcangeli e422fd2c96 [PATCH] avoid -ENOMEM due reclaimable slab caches
This makes sure that reclaimable buffer headers and reclaimable inodes
are accounted properly during the overcommit checks.

Signed-off-by: Andrea Arcangeli <andrea@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:30 -07:00
Martin Waitz 67be2dd1ba [PATCH] DocBook: fix some descriptions
Some KernelDoc descriptions are updated to match the current code.
No code changes.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:26 -07:00
Matt Mackall cd7619d6bf [PATCH] Exterminate PAGE_BUG
Remove PAGE_BUG - repalce it with BUG and BUG_ON.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:01 -07:00