Commit Graph

123 Commits

Author SHA1 Message Date
Eric Sandeen 8f64b32eb7 ext4: don't call jbd2_journal_force_commit_nested without journal
Running without a journal, I oopsed when I ran out of space,
because we called jbd2_journal_force_commit_nested() from
ext4_should_retry_alloc() without a journal.

This should take care of it, I think.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-26 00:57:35 -05:00
Jan Kara ebd3610b11 ext4: Fix deadlock in ext4_write_begin() and ext4_da_write_begin()
Functions ext4_write_begin() and ext4_da_write_begin() call
grab_cache_page_write_begin() without AOP_FLAG_NOFS. Thus it
can happen that page reclaim is triggered in that function
and it recurses back into the filesystem (or some other filesystem).
But this can lead to various problems as a transaction is already
started at that point. Add the necessary flag.

http://bugzilla.kernel.org/show_bug.cgi?id=11688

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-22 21:09:59 -05:00
Aneesh Kumar K.V 2acf2c261b ext4: Implement range_cyclic in ext4_da_writepages instead of write_cache_pages
With delayed allocation we lock the page in write_cache_pages() and
try to build an in memory extent of contiguous blocks.  This is needed
so that we can get large contiguous blocks request.  If range_cyclic
mode is enabled, write_cache_pages() will loop back to the 0 index if
no I/O has been done yet, and try to start writing from the beginning
of the range.  That causes an attempt to take the page lock of lower
index page while holding the page lock of higher index page, which can
cause a dead lock with another writeback thread.

The solution is to implement the range_cyclic behavior in
ext4_da_writepages() instead.

http://bugzilla.kernel.org/show_bug.cgi?id=12579

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-14 10:42:58 -05:00
Jan Kara 7f5aa21508 jbd2: Avoid possible NULL dereference in jbd2_journal_begin_ordered_truncate()
If we race with commit code setting i_transaction to NULL, we could
possibly dereference it.  Proper locking requires the journal pointer
(to access journal->j_list_lock), which we don't have.  So we have to
change the prototype of the function so that filesystem passes us the
journal pointer.  Also add a more detailed comment about why the
function jbd2_journal_begin_ordered_truncate() does what it does and
how it should be used.

Thanks to Dan Carpenter <error27@gmail.com> for pointing to the
suspitious code.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Joel Becker <joel.becker@oracle.com>
CC: linux-ext4@vger.kernel.org
CC: ocfs2-devel@oss.oracle.com
CC: mfasheh@suse.de
CC: Dan Carpenter <error27@gmail.com>
2009-02-10 11:15:34 -05:00
Theodore Ts'o b9ec63f78b ext4: Remove bogus BUG() check in ext4_bmap()
The code to support journal-less ext4 operation added a BUG to
ext4_bmap() which fired if there was no journal and the
EXT4_STATE_JDATA bit was set in the i_state field.  This caused
running the filefrag program (which uses the FIMBAP ioctl) to trigger
a BUG().

The EXT4_STATE_JDATA bit is only used for ext4_bmap(), and it's
harmless for the bit to be set.  We could add a check in
__ext4_journalled_writepage() and ext4_journalled_write_end() to only
set the EXT4_STATE_JDATA bit if the journal is present, but that adds
an extra test and jump instruction.  It's easier to simply remove the
BUG check.

http://bugzilla.kernel.org/show_bug.cgi?id=12568

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2009-01-30 00:00:24 -05:00
Theodore Ts'o e7f07968c1 ext4: Fix ext4_free_blocks() w/o a journal when files have indirect blocks
When trying to unlink a file with indirect blocks on a filesystem
without a journal, the "circular indirect block" sanity test was
getting falsely triggered.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-20 09:50:19 -05:00
Theodore Ts'o 06a279d636 ext4: only use i_size_high for regular files
Directories are not allowed to be bigger than 2GB, so don't use
i_size_high for anything other than regular files.  E2fsck should
complain about these inodes, but the simplest thing to do for the
kernel is to only use i_size_high for regular files.

This prevents an intentially corrupted filesystem from causing the
kernel to burn a huge amount of CPU and issuing error messages such
as:

EXT4-fs warning (device loop0): ext4_block_to_path: block 135090028 > max

Thanks to David Maciejak from Fortinet's FortiGuard Global Security
Research Team for reporting this issue.

http://bugzilla.kernel.org/show_bug.cgi?id=12375

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2009-01-17 18:41:37 -05:00
Linus Torvalds 2150edc6c5 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (57 commits)
  jbd2: Fix oops in jbd2_journal_init_inode() on corrupted fs
  ext4: Remove "extents" mount option
  block: Add Kconfig help which notes that ext4 needs CONFIG_LBD
  ext4: Make printk's consistently prefixed with "EXT4-fs: "
  ext4: Add sanity checks for the superblock before mounting the filesystem
  ext4: Add mount option to set kjournald's I/O priority
  jbd2: Submit writes to the journal using WRITE_SYNC
  jbd2: Add pid and journal device name to the "kjournald2 starting" message
  ext4: Add markers for better debuggability
  ext4: Remove code to create the journal inode
  ext4: provide function to release metadata pages under memory pressure
  ext3: provide function to release metadata pages under memory pressure
  add releasepage hooks to block devices which can be used by file systems
  ext4: Fix s_dirty_blocks_counter if block allocation failed with nodelalloc
  ext4: Init the complete page while building buddy cache
  ext4: Don't allow new groups to be added during block allocation
  ext4: mark the blocks/inode bitmap beyond end of group as used
  ext4: Use new buffer_head flag to check uninit group bitmaps initialization
  ext4: Fix the race between read_inode_bitmap() and ext4_new_inode()
  ext4: code cleanup
  ...
2009-01-08 17:14:59 -08:00
Eric Dumazet 179f7ebff6 percpu_counter: FBC_BATCH should be a variable
For NR_CPUS >= 16 values, FBC_BATCH is 2*NR_CPUS

Considering more and more distros are using high NR_CPUS values, it makes
sense to use a more sensible value for FBC_BATCH, and get rid of NR_CPUS.

A sensible value is 2*num_online_cpus(), with a minimum value of 32 (This
minimum value helps branch prediction in __percpu_counter_add())

We already have a hotcpu notifier, so we can adjust FBC_BATCH dynamically.

We rename FBC_BATCH to percpu_counter_batch since its not a constant
anymore.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:13 -08:00
Nick Piggin 54566b2c15 fs: symlink write_begin allocation context fix
With the write_begin/write_end aops, page_symlink was broken because it
could no longer pass a GFP_NOFS type mask into the point where the
allocations happened.  They are done in write_begin, which would always
assume that the filesystem can be entered from reclaim.  This bug could
cause filesystem deadlocks.

The funny thing with having a gfp_t mask there is that it doesn't really
allow the caller to arbitrarily tinker with the context in which it can be
called.  It couldn't ever be GFP_ATOMIC, for example, because it needs to
take the page lock.  The only thing any callers care about is __GFP_FS
anyway, so turn that into a single flag.

Add a new flag for write_begin, AOP_FLAG_NOFS.  Filesystems can now act on
this flag in their write_begin function.  Change __grab_cache_page to
accept a nofs argument as well, to honour that flag (while we're there,
change the name to grab_cache_page_write_begin which is more instructive
and does away with random leading underscores).

This is really a more flexible way to go in the end anyway -- if a
filesystem happens to want any extra allocations aside from the pagecache
ones in ints write_begin function, it may now use GFP_KERNEL (rather than
GFP_NOFS) for common case allocations (eg.  ocfs2_alloc_write_ctxt, for a
random example).

[kosaki.motohiro@jp.fujitsu.com: fix ubifs]
[kosaki.motohiro@jp.fujitsu.com: fix fuse]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Cleaned up the calling convention: just pass in the AOP flags
  untouched to the grab_cache_page_write_begin() function.  That
  just simplifies everybody, and may even allow future expansion of the
  logic.   - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-04 13:33:20 -08:00
Theodore Ts'o ba80b1019a ext4: Add markers for better debuggability
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-03 20:03:21 -05:00
Aneesh Kumar K.V 560671a0d3 ext4: Use high 16 bits of the block group descriptor's free counts fields
Rename the lower bits with suffix _lo and add helper
to access the values. Also rename bg_itable_unused_hi
to bg_pad as in e2fsprogs.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-05 22:20:24 -05:00
Duane Griffin e83c1397ca ext4: ensure fast symlinks are NUL-terminated
Ensure fast symlink targets are NUL-terminated, even if corrupted
on-disk.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: adilger@sun.com
Cc: linux-ext4@vger.kernel.org
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:39 -05:00
Aneesh Kumar K.V ed9b3e3379 ext4: Mark the buffer_heads as dirty and uptodate after prepare_write
We need to make sure we mark the buffer_heads as dirty and uptodate
so that block_write_full_page write them correctly.

This fixes mmap corruptions that can occur in low memory situations.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-11-07 09:06:45 -05:00
Aneesh Kumar K.V 3a06d778df ext4: sparse fixes
* Change EXT4_HAS_*_FEATURE to return a boolean
* Add a function prototype for ext4_fiemap() in ext4.h
* Make ext4_ext_fiemap_cb() and ext4_xattr_fiemap() be static functions
* Add lock annotations to mb_free_blocks()

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-11-22 15:04:59 -05:00
Theodore Ts'o ac51d83705 ext4: calculate journal credits correctly
This fixes a 2.6.27 regression which was introduced in commit a02908f1.

We weren't passing the chunk parameter down to the two subections,
ext4_indirect_trans_blocks() and ext4_ext_index_trans_blocks(), with
the result that massively overestimate the amount of credits needed by
ext4_da_writepages, especially in the non-extents case.  This causes
failures especially on /boot partitions, which tend to be small and
non-extent using since GRUB doesn't handle extents.

This patch fixes the bug reported by Joseph Fannin at:
http://bugzilla.kernel.org/show_bug.cgi?id=11964

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-11-06 16:49:36 -05:00
Theodore Ts'o 498e5f2415 ext4: Change unsigned long to unsigned int
Convert the unsigned longs that are most responsible for bloating the
stack usage on 64-bit systems.

Nearly all places in the ext3/4 code which uses "unsigned long" is
probably a bug, since on 32-bit systems a ulong a 32-bits, which means
we are wasting stack space on 64-bit systems.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-11-05 00:14:04 -05:00
Frank Mayhar 0390131ba8 ext4: Allow ext4 to run without a journal
A few weeks ago I posted a patch for discussion that allowed ext4 to run
without a journal.  Since that time I've integrated the excellent
comments from Andreas and fixed several serious bugs.  We're currently
running with this patch and generating some performance numbers against
both ext2 (with backported reservations code) and ext4 with and without
a journal.  It just so happens that running without a journal is
slightly faster for most everything.

We did
	iozone -T -t 4 s 2g -r 256k -T -I -i0 -i1 -i2

which creates 4 threads, each of which create and do reads and writes on
a 2G file, with a buffer size of 256K, using O_DIRECT for all file opens
to bypass the page cache.  Results:

                     ext2        ext4, default   ext4, no journal
  initial writes   13.0 MB/s        15.4 MB/s          15.7 MB/s
  rewrites         13.1 MB/s        15.6 MB/s          15.9 MB/s
  reads            15.2 MB/s        16.9 MB/s          17.2 MB/s
  re-reads         15.3 MB/s        16.9 MB/s          17.2 MB/s
  random readers    5.6 MB/s         5.6 MB/s           5.7 MB/s
  random writers    5.1 MB/s         5.3 MB/s           5.4 MB/s 

So it seems that, so far, this was a useful exercise.

Signed-off-by: Frank Mayhar <fmayhar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-07 00:06:22 -05:00
Aneesh Kumar K.V 791b7f0895 ext4: Fix the delalloc writepages to allocate blocks at the right offset.
When iterating through the pages which have mapped buffer_heads, we
failed to update the b_state value. This results in allocating blocks
at logical offset 0.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2009-01-05 21:50:43 -05:00
Theodore Ts'o 2a21e37e48 ext4: tone down ext4_da_writepages warnings
If the filesystem has errors, ext4_da_writepages() will return a *lot*
of errors, including lots and lots of stack dumps.  While it's true
that we are dropping user data on the floor, which is unfortunate, the
stack dumps aren't helpful, and they tend to obscure the true original
root cause of the problem.  So in the case where the filesystem has
aborted, return an EROFS right away.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-11-05 09:22:24 -05:00
Theodore Ts'o 815a113068 ext4: remove ext4_new_blocks() and call ext4_mb_new_blocks() directly
There was only one caller of the compatibility function
ext4_new_blocks(), in balloc.c's ext4_alloc_blocks().  Change it to
call ext4_mb_new_blocks() directly, and remove ext4_new_blocks()
altogether.  This cleans up the code, by removing two extra functions
from the call chain, and hopefully saving some stack usage.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-01 23:59:43 -05:00
Alexander Beregalov 8f72fbdf0d ext4: fix printk format warning
fs/ext4/balloc.c:607: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64'
fs/ext4/inode.c:1822: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64'
fs/ext4/inode.c:1824: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64'

Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2008-10-29 17:13:08 -04:00
Theodore Ts'o f287a1a561 ext4: Remove automatic enabling of the HUGE_FILE feature flag
If the HUGE_FILE feature flag is not set, don't allow the creation of
large files, instead of automatically enabling the feature flag.
Recent versions of mke2fs will set the HUGE_FILE flag automatically
anyway for ext4 filesystems.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-16 22:50:48 -04:00
Aneesh Kumar K.V 22208dedbd ext4: Fix file fragmentation during large file write.
The range_cyclic writeback mode uses the address_space writeback_index
as the start index for writeback.  With delayed allocation we were
updating writeback_index wrongly resulting in highly fragmented file.
This patch reduces the number of extents reduced from 4000 to 27 for a
3GB file.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2008-10-16 10:10:36 -04:00
Aneesh Kumar K.V af6f029d38 ext4: Use tag dirty lookup during mpage_da_submit_io
This enables us to drop the range_cont writeback mode
use from ext4_da_writepages.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2008-10-14 09:20:19 -04:00
Theodore Ts'o 03010a3350 ext4: Rename ext4dev to ext4
The ext4 filesystem is getting stable enough that it's time to drop
the "dev" prefix.  Also remove the requirement for the TEST_FILESYS
flag.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-10 20:02:48 -04:00
Eric Sandeen 6873fa0de1 Hook ext4 to the vfs fiemap interface.
ext4_ext_walk_space() was reinstated to be used for iterating over file
extents with a callback; it is used by the ext4 fiemap implementation.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-ext4@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
2008-10-07 00:46:36 -04:00
Theodore Ts'o c2ea3fde61 ext4: Remove old legacy block allocator
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-10 09:40:52 -04:00
Theodore Ts'o 240799cdf2 ext4: Use readahead when reading an inode from the inode table
With modern hard drives, reading 64k takes roughly the same time as
reading a 4k block.  So request readahead for adjacent inode table
blocks to reduce the time it takes when iterating over directories
(especially when doing this in htree sort order) in a cold cache case.
With this patch, the time it takes to run "git status" on a kernel
tree after flushing the caches via "echo 3 > /proc/sys/vm/drop_caches"
is reduced by 21%.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-09 23:53:47 -04:00
Aneesh Kumar K.V cf17fea657 ext4: Properly update i_disksize.
With delayed allocation we use i_data_sem to update i_disksize.  We need
to update i_disksize only if the new size specified is greater than the
current value and we need to make sure we don't race with other
i_disksize update.  With delayed allocation we will switch to the
write_begin function for non-delayed allocation if we are low on free
blocks.  This means the write_begin function for non-delayed allocation
also needs to use the same locking.

We also need to check and update i_disksize even if the new size is less
that inode.i_size because of delayed allocation.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-13 13:06:18 -04:00
Aneesh Kumar K.V ae4d537211 ext4: truncate block allocated on a failed ext4_write_begin
For blocksize < pagesize we need to remove blocks that got allocated in
block_write_begin() if we fail with ENOSPC for later blocks.
block_write_begin() internally does this if it allocated pages locally.
This makes sure we don't have blocks outside inode.i_size during ENOSPC.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-13 13:10:25 -04:00
Aneesh Kumar K.V df22291ff0 ext4: Retry block allocation if we have free blocks left
When we truncate files, the meta-data blocks released are not reused
untill we commit the truncate transaction.  That means delayed get_block
request will return ENOSPC even if we have free blocks left.  Force a
journal commit and retry block allocation if we get ENOSPC with free
blocks left.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 23:05:34 -04:00
Aneesh Kumar K.V 166348dd37 ext4: Don't add the inode to journal handle until after the block is allocated
Make sure we don't add the inode to the journal handle until after the
block allocation, so that a journal commit will not include the inode in
case of block allocation failure.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 23:08:40 -04:00
Aneesh Kumar K.V 79f0be8d2e ext4: Switch to non delalloc mode when we are low on free blocks count.
The delayed allocation code allocates blocks during writepages(), which
can not handle block allocation failures.  To deal with this, we switch
away from delayed allocation mode when we are running low on free
blocks.  This also allows us to avoid needing to reserve a large number
of meta-data blocks in case all of the requested blocks are
discontiguous.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-08 23:13:30 -04:00
Aneesh Kumar K.V 6bc6e63fcd ext4: Add percpu dirty block accounting.
This patch adds dirty block accounting using percpu_counters.  Delayed
allocation block reservation is now done by updating dirty block
counter.  In a later patch we switch to non delalloc mode if the
filesystem free blocks is greater than 150% of total filesystem dirty
blocks

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao<cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-10 09:39:00 -04:00
Aneesh Kumar K.V 030ba6bc67 ext4: Retry block reservation
During block reservation if we don't have enough blocks left, retry
block reservation with smaller block counts.  This makes sure we try
fallocate and DIO with smaller request size and don't fail early.  The
delayed allocation reservation cannot try with smaller block count. So
retry block reservation to handle temporary disk full conditions.  Also
print free blocks details if we fail block allocation during writepages.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 23:14:50 -04:00
Aneesh Kumar K.V a30d542a00 ext4: Make sure all the block allocation paths reserve blocks
With delayed allocation we need to make sure block are reserved before
we attempt to allocate them. Otherwise we get block allocation failure
(ENOSPC) during writepages which cannot be handled. This would mean
silent data loss (We do a printk stating data will be lost). This patch
updates the DIO and fallocate code path to do block reservation before
block allocation. This is needed to make sure parallel DIO and fallocate
request doesn't take block out of delayed reserve space.

When free blocks count go below a threshold we switch to a slow patch
which looks at other CPU's accumulated percpu counter values.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-09 10:56:23 -04:00
Aneesh Kumar K.V c4a0c46ec9 ext4: invalidate pages if delalloc block allocation fails.
We are a bit agressive in invalidating all the pages. But
it is ok because we really don't know why the block allocation
failed and it is better to come of the writeback path
so that user can look for more info.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2008-08-19 21:08:18 -04:00
Theodore Ts'o af5bc92dde ext4: Fix whitespace checkpatch warnings/errors
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-09-08 22:25:24 -04:00
Aneesh Kumar K.V 5e745b041f ext4: Fix small file fragmentation
For small file block allocations, mballoc uses per cpu prealloc
space.  Use goal block when searching for the right prealloc
space.  Also make sure ext4_da_writepages tries to write
all the pages for small files in single attempt

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-18 18:00:57 -04:00
Mingming Cao 525f4ed8dc ext4: journal credit fix for the delayed allocation's writepages() function
Previous delalloc writepages implementation started a new transaction
outside of a loop which called get_block() to do the block allocation.
Since we didn't know exactly how many blocks would need to be allocated,
the estimated journal credits required was very conservative and caused
many issues.

With the reworked delayed allocation, a new transaction is created for
each get_block(), thus we don't need to guess how many credits for the
multiple chunk of allocation.  We start every transaction with enough
credits for inserting a single exent.  When estimate the credits for
indirect blocks to allocate a chunk of blocks, we need to know the
number of data blocks to allocate.  We use the total number of reserved
delalloc datablocks; if that is too big, for non-extent files, we need
to limit the number of blocks to EXT4_MAX_TRANS_BLOCKS.

Code cleanup from Aneesh.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Reviewed-off-by:  Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-19 22:15:58 -04:00
Aneesh Kumar K.V a1d6cc563b ext4: Rework the ext4_da_writepages() function
With the below changes we reserve credit needed to insert only one
extent resulting from a call to single get_block.  This makes sure we
don't take too much journal credits during writeout.  We also don't
limit the pages to write.  That means we loop through the dirty pages
building largest possible contiguous block request.  Then we issue a
single get_block request.  We may get less block that we requested.  If
so we would end up not mapping some of the buffer_heads.  That means
those buffer_heads are still marked delay.  Later in the writepage
callback via __mpage_writepage we redirty those pages.

We should also not limit/throttle wbc->nr_to_write in the filesystem
writepages callback. That cause wrong behaviour in
generic_sync_sb_inodes caused by wbc->nr_to_write being <= 0

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-19 21:55:02 -04:00
Mingming Cao f3bd1f3fa8 ext4: journal credits reservation fixes for DIO, fallocate
DIO and fallocate credit calculation is different than writepage, as
they do start a new journal right for each call to ext4_get_blocks_wrap().
This patch uses the helper function in DIO and fallocate case, passing
a flag indicating that the modified data are contigous thus could account
less indirect/index blocks.

This patch also fixed the journal credit reservation for direct I/O
(DIO).  Previously the estimated credits for DIO only was calculated for
non-extent files, which was not enough if the file is extent-based.

Also fixed was fallocate double-counting credits for modifying the the
superblock.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-19 22:16:03 -04:00
Mingming Cao a02908f19c ext4: journal credits calulation cleanup and fix for non-extent writepage
When considering how many journal credits are needed for modifying a
chunk of data, we need to account for the super block, inode block,
quota blocks and xattr block, indirect/index blocks, also, group bitmap
and group descriptor blocks for new allocation (including data and
indirect/index blocks). There are many places in ext4 do the calculation
on their own and often missed one or two meta blocks, and often they
assume single block allocation, and did not considering the multile
chunk of allocation case.

This patch is trying to cleanup current journal credit code, provides
some common helper funtion to calculate the journal credits, to be used
for writepage, writepages, DIO, fallocate, migration, defrag, and for
both nonextent and extent files.

This patch modified the writepage/write_begin credit caculation for
nonextent files, to use the new helper function. It also fixed the
problem that writepage on nonextent files did not consider the case
blocksize <pagesize, thus could possibelly need multiple block
allocation in a single transaction.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-19 22:16:07 -04:00
Mingming Cao cd21322616 ext4: Fix delalloc release block reservation for truncate
Ext4 will release the reserved blocks for delayed allocations when
inode is truncated/unlinked.  If there is no reserved block at all, we
shouldn't need to do so.  But current code still tries to release the
reserved blocks regardless whether the counters's value is 0.
Continue to do that causes the later calculation to go wrong and a
kernel BUG_ON() caught that. This doesn't happen for extent-based
files, as the calculation for 0 reserved blocks was right for extent
based file.

This patch fixed the kernel BUG() due to above reason.  It adds checks
for 0 to avoid unnecessary release and fix calculation for non-extent
files.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-19 22:16:59 -04:00
Theodore Ts'o b4df203085 ext4: Fix potential truncate BUG due to i_prealloc_list being non-empty
We need to call ext4_discard_reservation() earlier in ext4_truncate(),
to avoid a BUG() in ext4_mb_return_to_preallocation(), which is called
(ultimately) by ext4_free_blocks().  So we must ditch the blocks on
i_prealloc_list before we start freeing the data blocks.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-13 21:44:34 -04:00
Aneesh Kumar K.V bf068ee266 ext4: Handle unwritten extent properly with delayed allocation
When using fallocate the buffer_heads are marked unwritten and unmapped.
We need to map them in the writepages after a get_block.  Otherwise we
split the uninit extents, but never write the content to disk.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-19 22:16:43 -04:00
Eric Sandeen 7d55992d60 ext4: remove write-only variables from ext4_ordered_write_end
The variables 'from' and 'to' are not used anywhere.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-08-02 21:22:18 -04:00
Theodore Ts'o 2b2d6d0197 ext4: Cleanup whitespace and other miscellaneous style issues
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-07-26 16:15:44 -04:00
Aneesh Kumar K.V 12219aea6b ext4: Cleanup the block reservation code path
The truncate patch should not use the i_allocated_meta_blocks
value. So add seperate functions to be used in the truncate
and alloc path. We also need to release the meta-data block
that we reserved for the blocks that we are truncating.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2008-07-17 16:12:08 -04:00