Commit graph

219 commits

Author SHA1 Message Date
Theodore Ts'o
3661d28615 ext4: Fix include/trace/events/ext4.h to work with Systemtap
Using relative pathnames in #include statements interacts badly with
SystemTap, since the fs/ext4/*.h header files are not packaged up as
part of a distribution kernel's header files.  Since systemtap doesn't
use TP_fast_assign(), we can use a blind structure definition and then
make sure the needed header files are defined before the ext4 source
files #include the trace/events/ext4.h header file.

https://bugzilla.redhat.com/show_bug.cgi?id=512478

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-14 22:59:50 -04:00
Theodore Ts'o
7ad9bb651f ext4: Fix initalization of s_flex_groups
The s_flex_groups array should have been initialized using atomic_add
to sum up the free counts from the block groups that make up a
flex_bg.  By using atomic_set, the value of the s_flex_groups array
was set to the values of the last block group in the flex_bg.  

The impact of this bug is that the block and inode allocation
algorithms might not pick the best flex_bg for new allocation.

Thanks to Damien Guibouret for pointing out this problem!

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-11 16:51:28 -04:00
Theodore Ts'o
71290b368a ext4: Don't update superblock write time when filesystem is read-only
This avoids updating the superblock write time when we are mounting
the root file system read/only but we need to replay the journal; at
that point, for people who are east of GMT and who make their clock
tick in localtime for Windows bug-for-bug compatibility, and this will
cause e2fsck to complain and force a full file system check.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-10 17:31:04 -04:00
Theodore Ts'o
d0646f7b63 ext4: Remove journal_checksum mount option and enable it by default
There's no real cost for the journal checksum feature, and we should
make sure it is enabled all the time.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-05 12:50:43 -04:00
Eric Sandeen
a13fb1a453 ext4: Add feature set check helper for mount & remount paths
A user reported that although his root ext4 filesystem was mounting
fine, other filesystems would not mount, with the:

"Filesystem with huge files cannot be mounted RDWR without CONFIG_LBDAF"

error on his 32-bit box built without CONFIG_LBDAF.  This is because
the test at mount time for this situation was not being re-checked
on remount, and the normal boot process makes an ro->rw transition,
so this was being missed.

Refactor to make a common helper function to test the filesystem
features against the type of mount request (RO vs. RW) so that we 
stay consistent.

Addresses Red-Hat-Bugzilla: #517650

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-08-18 00:20:23 -04:00
Eric Sandeen
bf43d84b18 ext4: reject too-large filesystems on 32-bit kernels
ext4 will happily mount a > 16T filesystem on a 32-bit box, but
this is not safe; writes to the block device will wrap past 16T
and the page cache can't index past 16T (232 index * 4k pages).

Adding another test to the existing "too many sectors" test
should do the trick.

Add a comment, a relevant return value, and fix the reference
to the CONFIG_LBD(AF) option as well.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-08-17 23:48:51 -04:00
Theodore Ts'o
78f1ddbb49 ext4: Avoid null pointer dereference when decoding EROFS w/o a journal
We need to check to make sure a journal is present before checking the
journal flags in ext4_decode_error().

Signed-off-by: Eric Sesterhenn <eric.sesterhenn@lsexperts.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-07-27 23:09:47 -04:00
Al Viro
d4bfe2f76d switch ext4 to inode->i_acl
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-24 08:17:04 -04:00
Linus Torvalds
31583d6acf Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  Fix kernel-doc parameter name typo in blk-settings.c:
  block: rename CONFIG_LBD to CONFIG_LBDAF
  block: Fix bounce_pfn setting
  hd: stop defining MAJOR_NR
2009-06-19 17:43:04 -07:00
Bartlomiej Zolnierkiewicz
90c699a9ee block: rename CONFIG_LBD to CONFIG_LBDAF
Follow-up to "block: enable by default support for large devices
and files on 32-bit archs".

Rename CONFIG_LBD to CONFIG_LBDAF to:
- allow update of existing [def]configs for "default y" change
- reflect that it is used also for large files support nowadays

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-06-19 08:08:50 +02:00
Andreas Dilger
11013911da ext4: teach the inode allocator to use a goal inode number
Enhance the inode allocator to take a goal inode number as a
paremeter; if it is specified, it takes precedence over Orlov or
parent directory inode allocation algorithms.

The extents migration function uses the goal inode number so that the
extent trees allocated the migration function use the correct flex_bg.
In the future, the goal inode functionality will also be used to
allocate an adjacent inode for the extended attributes.

Also, for testing purposes the goal inode number can be specified via
/sys/fs/{dev}/inode_goal.  This can be useful for testing inode
allocation beyond 2^32 blocks on very large filesystems.

Signed-off-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-06-13 11:45:35 -04:00
Theodore Ts'o
4ab2f15b7f ext4: move the abort flag from s_mount_opts to s_mount_flags
We're running out of space in the mount options word, and
EXT4_MOUNT_ABORT isn't really a mount option, but a run-time flag.  So
move it to become EXT4_MF_FS_ABORTED in s_mount_flags.

Also remove bogus ext2_fs.h / ext4.h simultaneous #include protection,
which can never happen.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-06-13 10:09:36 -04:00
Theodore Ts'o
7f4520cc62 ext4: change s_mount_opt to be an unsigned int
We can only fit 32 options in s_mount_opt because an unsigned long is
32-bits on a x86 machine.  So use an unsigned int to save space on
64-bit platforms.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-06-13 10:09:41 -04:00
Alessio Igor Bogani
337eb00a2c Push BKL down into ->remount_fs()
[xfs, btrfs, capifs, shmem don't need BKL, exempt]

Signed-off-by: Alessio Igor Bogani <abogani@texware.it>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:11 -04:00
Christoph Hellwig
ebc1ac1645 ->write_super lock_super pushdown
Push down lock_super into ->write_super instances and remove it from the
caller.

Following filesystem don't need ->s_lock in ->write_super and are skipped:

 * bfs, nilfs2 - no other uses of s_lock and have internal locks in
	->write_super
 * ext2 - uses BKL in ext2_write_super and has internal calls without s_lock
 * reiserfs - no other uses of s_lock as has reiserfs_write_lock (BKL) in
 	->write_super
 * xfs - no other uses of s_lock and uses internal lock (buffer lock on
	superblock buffer) to serialize ->write_super.  Also xfs_fs_write_super
	is superflous and will go away in the next merge window

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:09 -04:00
Al Viro
bbd6851a32 Push lock_super() into the ->remount_fs() of filesystems that care about it
Note that since we can't run into contention between remount_fs and write_super
(due to exclusion on s_umount), we have to care only about filesystems that
touch lock_super() on their own.  Out of those ext3, ext4, hpfs, sysv and ufs
do need it; fat doesn't since its ->remount_fs() only accesses assign-once
data (basically, it's "we have no atime on directories and only have atime on
files for vfat; force nodiratime and possibly noatime into *flags").

[folded a build fix from hch]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:08 -04:00
Christoph Hellwig
6cfd014842 push BKL down into ->put_super
Move BKL into ->put_super from the only caller.  A couple of
filesystems had trivial enough ->put_super (only kfree and NULLing of
s_fs_info + stuff in there) to not get any locking: coda, cramfs, efs,
hugetlbfs, omfs, qnx4, shmem, all others got the full treatment.  Most
of them probably don't need it, but I'd rather sort that out individually.
Preferably after all the other BKL pushdowns in that area.

[AV: original used to move lock_super() down as well; these changes are
removed since we don't do lock_super() at all in generic_shutdown_super()
now]
[AV: fuse, btrfs and xfs are known to need no damn BKL, exempt]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:07 -04:00
Al Viro
a9e220f832 No need to do lock_super() for exclusion in generic_shutdown_super()
We can't run into contention on it.  All other callers of lock_super()
either hold s_umount (and we have it exclusive) or hold an active
reference to superblock in question, which prevents the call of
generic_shutdown_super() while the reference is held.  So we can
replace lock_super(s) with get_fs_excl() in generic_shutdown_super()
(and corresponding change for unlock_super(), of course).

Since ext4 expects s_lock held for its put_super, take lock_super()
into it.  The rest of filesystems do not care at all.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:07 -04:00
Christoph Hellwig
8c85e12512 remove ->write_super call in generic_shutdown_super
We just did a full fs writeout using sync_filesystem before, and if
that's not enough for the filesystem it can perform it's own writeout
in ->put_super, which many filesystems already do.

Move a call to foofs_write_super into every foofs_put_super for now to
guarantee identical behaviour until it's cleaned up by the individual
filesystem maintainers.

Exceptions:

 - affs already has identical copy & pasted code at the beginning of
   affs_put_super so no need to do it twice.
 - xfs does the right thing without it and I have changes pending for
   the xfs tree touching this are so I don't really need conflicts
   here..

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:06 -04:00
Linus Torvalds
c9059598ea Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block: (153 commits)
  block: add request clone interface (v2)
  floppy: fix hibernation
  ramdisk: remove long-deprecated "ramdisk=" boot-time parameter
  fs/bio.c: add missing __user annotation
  block: prevent possible io_context->refcount overflow
  Add serial number support for virtio_blk, V4a
  block: Add missing bounce_pfn stacking and fix comments
  Revert "block: Fix bounce limit setting in DM"
  cciss: decode unit attention in SCSI error handling code
  cciss: Remove no longer needed sendcmd reject processing code
  cciss: change SCSI error handling routines to work with interrupts enabled.
  cciss: separate error processing and command retrying code in sendcmd_withirq_core()
  cciss: factor out fix target status processing code from sendcmd functions
  cciss: simplify interface of sendcmd() and sendcmd_withirq()
  cciss: factor out core of sendcmd_withirq() for use by SCSI error handling code
  cciss: Use schedule_timeout_uninterruptible in SCSI error handling code
  block: needs to set the residual length of a bidi request
  Revert "block: implement blkdev_readpages"
  block: Fix bounce limit setting in DM
  Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt
  ...

Manually fix conflicts with tracing updates in:
	block/blk-sysfs.c
	drivers/ide/ide-atapi.c
	drivers/ide/ide-cd.c
	drivers/ide/ide-floppy.c
	drivers/ide/ide-tape.c
	include/trace/events/block.h
	kernel/trace/blktrace.c
2009-06-11 11:10:35 -07:00
Eric Sandeen
b31e15527a ext4: Change all super.c messages to print the device
This patch changes ext4 super.c to include the device name with all 
warning/error messages, by using a new utility function ext4_msg. 
It's a rather large patch, but very mechanic. I left debug printks
alone.

This is a straightforward port of a patch which Andi Kleen did for
ext3.

Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-06-04 17:36:36 -04:00
Andreas Dilger
0b8e58a140 ext4: super.c whitespace cleanup
Cleanup of whitespace and formatting.  Initially driven by confusing indents
for the ext4_{block,inode}_bitmap() et. al. helper routines, but figured I'd
cleanup some other 80-column wrapping and other indenting problems at the
same time.

Signed-off-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-06-03 17:59:28 -04:00
Theodore Ts'o
88b6edd17c ext4: Clean up calls to ext4_get_group_desc()
If the caller isn't planning on modifying the block group descriptors,
there's no need to pass in a pointer to a struct buffer_head.  Nuking
this saves a tiny amount of CPU time and stack space usage.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-25 11:50:39 -04:00
Martin K. Petersen
e1defc4ff0 block: Do away with the notion of hardsect_size
Until now we have had a 1:1 mapping between storage device physical
block size and the logical block sized used when addressing the device.
With SATA 4KB drives coming out that will no longer be the case.  The
sector size will be 4KB but the logical block size will remain
512-bytes.  Hence we need to distinguish between the physical block size
and the logical ditto.

This patch renames hardsect_size to logical_block_size.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:54 +02:00
Manish Katiyar
f68301656b ext4: Fix memory leak in ext4_fill_super() in case of a failed mount
Signed-off-by: Manish Katiyar <mkatiyar@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-17 23:52:44 -04:00
Theodore Ts'o
6fd058f779 ext4: Add a comprehensive block validity check to ext4_get_blocks()
To catch filesystem bugs or corruption which could lead to the
filesystem getting severly damaged, this patch adds a facility for
tracking all of the filesystem metadata blocks by contiguous regions
in a red-black tree.  This allows quick searching of the tree to
locate extents which might overlap with filesystem metadata blocks.

This facility is also used by the multi-block allocator to assure that
it is not allocating blocks out of the system zone, as well as by the
routines used when reading indirect blocks and extents information
from disk to make sure their contents are valid.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-17 15:38:01 -04:00
Aneesh Kumar K.V
955ce5f5be ext4: Convert ext4_lock_group to use sb_bgl_lock
We have sb_bgl_lock() and ext4_group_info.bb_state
bit spinlock to protech group information. The later is only
used within mballoc code. Consolidate them to use sb_bgl_lock().
This makes the mballoc.c code much simpler and also avoid
confusion with two locks protecting same info.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-02 20:35:09 -04:00
Curt Wohlgemuth
f40339031b ext4: Make the length of the mb_history file tunable
In memory-constrained systems with many partitions, the ~68K for each
partition for the mb_history buffer can be excessive.

This patch adds a new mount option, mb_history_length, as well as a
way of setting the default via a module parameter (or via a sysfs
parameter in /sys/module/ext4/parameter/default_mb_history_length).
If the mb_history_length is set to zero, the mb_history facility is
disabled entirely.

Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 20:27:20 -04:00
Theodore Ts'o
bb23c20a85 ext4: Move fs/ext4/group.h into ext4.h
Move the function prototypes in group.h into ext4.h so they are all
defined in one place.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 19:44:44 -04:00
Theodore Ts'o
596397b77c ext4: Move fs/ext4/namei.h into ext4.h
The fs/ext4/namei.h header file had only a single function
declaration, and should have never been a standalone file.  Move it
into ext4.h, where should have been from the beginning.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 13:49:15 -04:00
Theodore Ts'o
9bffad1ed2 ext4: convert instrumentation from markers to tracepoints
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-06-17 11:48:11 -04:00
Theodore Ts'o
32ed5058ce ext4: Replace lock/unlock_super() with an explicit lock for resizing
Use a separate lock to protect s_groups_count and the other block
group descriptors which get changed via an on-line resize operation,
so we can stop overloading the use of lock_super().
    
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-25 22:53:39 -04:00
Theodore Ts'o
3b9d4ed266 ext4: Replace lock/unlock_super() with an explicit lock for the orphan list
Use a separate lock to protect the orphan list, so we can stop
overloading the use of lock_super().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-25 22:54:04 -04:00
Theodore Ts'o
a63c9eb2ce ext4: ext4_mark_recovery_complete() doesn't need to use lock_super
The function ext4_mark_recovery_complete() is called from two call
paths: either (a) while mounting the filesystem, in which case there's
no danger of any other CPU calling write_super() until the mount is
completed, and (b) while remounting the filesystem read-write, in
which case the fs core has already locked the superblock.  This also
allows us to take out a very vile unlock_super()/lock_super() pair in
ext4_remount().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 01:59:42 -04:00
Theodore Ts'o
114e9fc907 ext4: Remove outdated comment about lock_super()
ext4_fill_super() is no longer called by read_super(), and it is no
longer called with the superblock locked.  The
unlock_super()/lock_super() is no longer present, so this comment is
entirely superfluous.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-25 15:48:07 -04:00
Theodore Ts'o
8df9675f8b ext4: Avoid races caused by on-line resizing and SMP memory reordering
Ext4's on-line resizing adds a new block group and then, only at the
last step adjusts s_groups_count.  However, it's possible on SMP
systems that another CPU could see the updated the s_group_count and
not see the newly initialized data structures for the just-added block
group.  For this reason, it's important to insert a SMP read barrier
after reading s_groups_count and before reading any (for example) the
new block group descriptors allowed by the increased value of
s_groups_count.

Unfortunately, we rather blatently violate this locking protocol
documented in fs/ext4/resize.c.  Fortunately, (1) on-line resizes
happen relatively rarely, and (2) it seems rare that the filesystem
code will immediately try to use just-added block group before any
memory ordering issues resolve themselves.  So apparently problems
here are relatively hard to hit, since ext3 has been vulnerable to the
same issue for years with no one apparently complaining.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 08:50:38 -04:00
Theodore Ts'o
9ca92389c5 ext4: Use separate super_operations structure for no_journal filesystems
By using a separate super_operations structure for filesystems that
have and don't have journals, we can simply ext4_write_super() ---
which is only needed when no journal is present --- and ext4_freeze(),
ext4_unfreeze(), and ext4_sync_fs(), which are only needed when the
journal is present.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 12:52:25 -04:00
Theodore Ts'o
7234ab2a55 ext4: Fix and simplify s_dirt handling
The s_dirt flag wasn't completely handled correctly, but it didn't
really matter when journalling was enabled.  It turns out that when
ext4 runs without a journal, we don't clear s_dirt in places where we
should have, with the result that the high-level write_super()
function was writing the superblock when it wasn't necessary.

So we fix this by making ext4_commit_super() clear the s_dirt flag,
and removing many of the other places where s_dirt is manipulated.
When journalling is enabled, the s_dirt flag might be left set more
often, but s_dirt really doesn't matter when journalling is enabled.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-30 21:24:04 -04:00
Theodore Ts'o
e2d670523c ext4: Simplify ext4_commit_super()'s function signature
The ext4_commit_super() function took both a struct super_block * and
a struct ext4_super_block *, but the struct ext4_super_block can be
derived from the struct super_block.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 00:33:44 -04:00
Theodore Ts'o
f7c439504c ext4: Use is_power_of_2() for clarity
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-24 23:31:59 -04:00
Theodore Ts'o
c5ca7c7636 ext4: Fallback to vmalloc if kmalloc can't allocate s_flex_groups array
For very large filesystems, the s_flex_groups array can get quite big.
For example, a filesystem that can be resized up to 16TB will have
8192 flex groups (assuming the default flex_bg size of 16), so the
array is 96k, which is *very* marginal for kmalloc().  On the other
hand, a 160GB filesystem without the resize_inode feature will only
require 960 bytes.  So we try to allocate the array first using
kmalloc(), and if that fails, we'll try to use vmalloc() instead.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-27 22:48:48 -04:00
From: Thiemo Nagel
0f2ddca66d ext4: check block device size on mount
Signed-off-by: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-07 14:07:47 -04:00
Theodore Ts'o
06705bff91 ext4: Regularize mount options
Add support for using the mount options "barrier" and "nobarrier", and
"auto_da_alloc" and "noauto_da_alloc", which is more consistent than
"barrier=<0|1>" or "auto_da_alloc=<0|1>".  Most other ext3/ext4 mount
options use the foo/nofoo naming convention.  We allow the old forms
of these mount options for backwards compatibility.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-28 10:59:57 -04:00
Theodore Ts'o
afd4672dc7 ext4: Add auto_da_alloc mount option
Add a mount option which allows the user to disable automatic
allocation of blocks whose allocation by delayed allocation when the
file was originally truncated or when the file is renamed over an
existing file.  This feature is intended to save users from the
effects of naive application writers, but it reduces the effectiveness
of the delayed allocation code.  This mount option disables this
safety feature, which may be desirable for prodcutions systems where
the risk of unclean shutdowns or unexpected system crashes is low.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-16 23:12:23 -04:00
Theodore Ts'o
7d39db14a4 ext4: Use struct flex_groups to calculate get_orlov_stats()
Instead of looping over all of the block groups in a flex group
summing their summary statistics, start tracking used_dirs in struct
flex_groups, and use struct flex_groups instead.  This should save a
bit of CPU for mkdir-heavy workloads.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-04 19:31:53 -05:00
Theodore Ts'o
9f24e4208f ext4: Use atomic_t's in struct flex_groups
Reduce pressure on the sb_bgl_lock family of locks by using atomic_t's
to track the number of free blocks and inodes in each flex_group.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-04 19:09:10 -05:00
Theodore Ts'o
b713a5ec55 ext4: remove /proc tuning knobs
Remove tuning knobs in /proc/fs/ext4/<dev/* since they have been
replaced by knobs in sysfs at /sys/fs/ext4/<dev>/*.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-31 09:11:14 -04:00
Theodore Ts'o
3197ebdb13 ext4: Add sysfs support
Add basic sysfs support so that information about the mounted
filesystem and various tuning parameters can be accessed via
/sys/fs/ext4/<dev>/*.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-31 09:10:09 -04:00
Theodore Ts'o
afc32f7ee9 ext4: Track lifetime disk writes
Add a new superblock value which tracks the lifetime amount of writes
to the filesystem.  This is useful in estimating the amount of wear on
solid state drives (SSD's) caused by writes to the filesystem.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-28 19:39:58 -05:00
Pekka Enberg
705895b611 ext4: allocate ->s_blockgroup_lock separately
As spotted by kmemtrace, struct ext4_sb_info is 17664 bytes on 64-bit
which makes it a very bad fit for SLAB allocators.  The culprit of the
wasted memory is ->s_blockgroup_lock which can be as big as 16 KB when
NR_CPUS >= 32.

To fix that, allocate ->s_blockgroup_lock, which fits nicely in a order 2
page in the worst case, separately.  This shinks down struct ext4_sb_info
enough to fit a 2 KB slab cache so now we allocate 16 KB + 2 KB instead of
32 KB saving 14 KB of memory.

Acked-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-15 18:07:52 -05:00