Commit Graph

634 Commits

Author SHA1 Message Date
Theodore Ts'o 0568c51893 ext4: down i_data_sem only for read when walking tree for fiemap
Not sure why I put this in as down_write originally; all we are
doing is walking the tree, nothing will change under us and
concurrent reads should be no problem.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-17 23:31:23 -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
Theodore Ts'o 2ec0ae3ace ext4: Fix race in ext4_inode_info.i_cached_extent
If two CPU's simultaneously call ext4_ext_get_blocks() at the same
time, there is nothing protecting the i_cached_extent structure from
being used and updated at the same time.  This could potentially cause
the wrong location on disk to be read or written to, including
potentially causing the corruption of the block group descriptors
and/or inode table.

This bug has been in the ext4 code since almost the very beginning of
ext4's development.  Fortunately once the data is stored in the page
cache cache, ext4_get_blocks() doesn't need to be called, so trying to
replicate this problem to the point where we could identify its root
cause was *extremely* difficult.  Many thanks to Kevin Shanahan for
working over several months to be able to reproduce this easily so we
could finally nail down the cause of the corruption.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
2009-05-15 09:07:28 -04:00
Aneesh Kumar K.V 2a8964d63d ext4: Clear the unwritten buffer_head flag after the extent is initialized
The BH_Unwritten flag indicates that the buffer is allocated on disk
but has not been written; that is, the disk was part of a persistent
preallocation area.  That flag should only be set when a get_blocks()
function is looking up a inode's logical to physical block mapping.

When ext4_get_blocks_wrap() is called with create=1, the uninitialized
extent is converted into an initialized one, so the BH_Unwritten flag
is no longer appropriate.  Hence, we need to make sure the
BH_Unwritten is not left set, since the combination of BH_Mapped and
BH_Unwritten is not allowed; among other things, it will result ext4's
get_block() to be called over and over again during the write_begin
phase of write(2).

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-14 17:05:39 -04:00
Theodore Ts'o 2ac3b6e00a ext4: Clean up ext4_get_blocks() so it does not depend on bh_result->b_state
The ext4_get_blocks() function was depending on the value of
bh_result->b_state as an input parameter to decide whether or not
update the delalloc accounting statistics by calling
ext4_da_update_reserve_space().  We now use a separate flag,
EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE, to requests this update, so that
all callers of ext4_get_blocks() can clear map_bh.b_state before
calling ext4_get_blocks() without worrying about any consistency
issues.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-14 13:57:08 -04:00
Theodore Ts'o 2fa3cdfb31 ext4: Merge ext4_da_get_block_write() into mpage_da_map_blocks()
The static function ext4_da_get_block_write() was only used by
mpage_da_map_blocks().  So to simplify the code, merge that function
into mpage_da_map_blocks().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-14 09:29:45 -04:00
Aneesh Kumar K.V 33b9817e2a ext4: Use a fake block number for delayed new buffer_head
Use a very large unsigned number (~0xffff) as as the fake block number
for the delayed new buffer. The VFS should never try to write out this
number, but if it does, this will make it obvious.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-12 14:40:37 -04:00
Aneesh Kumar K.V 9c1ee184a3 ext4: Fix sub-block zeroing for writes into preallocated extents
We need to mark the buffer_head mapping preallocated space as new
during write_begin. Otherwise we don't zero out the page cache content
properly for a partial write. This will cause file corruption with
preallocation.

Now that we mark the buffer_head new we also need to have a valid
buffer_head blocknr so that unmap_underlying_metadata() unmaps the
correct block.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-13 18:36:58 -04:00
Theodore Ts'o a2dc52b5d1 ext4: Add BUG_ON debugging checks to noalloc_get_block_write()
Enforce that noalloc_get_block_write() is only called to map one block
at a time, and that it always is successful in finding a mapping for
given an inode's logical block block number if it is called with
create == 1.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-12 13:51:29 -04:00
Theodore Ts'o b920c75502 ext4: Add documentation to the ext4_*get_block* functions
This adds more documentation to various internal functions in
fs/ext4/inode.c, most notably ext4_ind_get_blocks(),
ext4_da_get_block_write(), ext4_da_get_block_prep(),
ext4_normal_get_block_write().

In addition, the static function ext4_normal_get_block_write() has
been renamed noalloc_get_block_write(), since it is used in many
places far beyond ext4_normal_writepage().

Plenty of warnings have been added to the noalloc_get_block_write()
function, since the way it is used is amazingly fragile.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-14 00:54:29 -04:00
Theodore Ts'o c217705733 ext4: Define a new set of flags for ext4_get_blocks()
The functions ext4_get_blocks(), ext4_ext_get_blocks(), and
ext4_ind_get_blocks() used an ad-hoc set of integer variables used as
boolean flags passed in as arguments.  Use a single flags parameter
and a setandard set of bitfield flags instead.  This saves space on
the call stack, and it also makes the code a bit more understandable.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-14 00:58:52 -04:00
Theodore Ts'o 12b7ac1768 ext4: Rename ext4_get_blocks_wrap() to be ext4_get_blocks()
Another function rename for clarity's sake.  The _wrap prefix simply
confuses people, and didn't add much people trying to follow the code
paths.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-14 00:57:44 -04:00
Theodore Ts'o e4d996ca80 ext4: Rename ext4_get_blocks_handle() to be ext4_ind_get_blocks()
The static function ext4_get_blocks_handle() is badly named.  Of
*course* it takes a handle.  Since its counterpart for extent-based
file is ext4_ext_get_blocks(), rename it to be ext4_ind_get_blocks().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-12 00:25:28 -04:00
Theodore Ts'o f888e652d7 ext4: Simplify function signature for ext4_da_get_block_write()
The function ext4_da_get_block_write() is called in exactly one write,
and the last argument, create, is always 1.  Remove it to simplify the
code slightly.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-12 00:21:29 -04:00
Vincent Minet bc8e67409c ext4: Fix spinlock assertions on UP systems
On UP systems without DEBUG_SPINLOCK, ext4_is_group_locked always fails
which triggers a BUG_ON() call.
This patch fixes it by using assert_spin_locked instead.

Signed-off-by: Vincent Minet <vincent@vincent-minet.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-15 08:33:18 -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
Theodore Ts'o eefd7f03b8 ext4: fix the length returned by fiemap for an unallocated extent
If the file's blocks have not yet been allocated because of delayed
allocation, the length of the extent returned by fiemap is incorrect.
This commit fixes this bug.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-02 19:05:37 -04:00
Eric Sandeen c9877b205f ext4: fix for fiemap last-block test
Carl Henrik Lunde reported and debugged this; the test for the
last allocated block was comparing bytes to blocks in this test:

	if (logical + length - 1 == EXT_MAX_BLOCK ||
	    ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK)
		flags |= FIEMAP_EXTENT_LAST;

so any extent which ended right at 4G was stopping the extent
walk.  Just replacing these values with the extent block &
length should fix it.

Also give blksize_bits a saner type, and reverse the order 
of the tests to make the more likely case tested first.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Tested-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 23:32:06 -04:00
Aneesh Kumar K.V abc8746eb9 ext4: hook fiemap operation for directories
Add fiemap callback for directories

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 22:54:32 -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 ca0faba0e8 ext4: Move the ext4_sb.h header file into ext4.h
There is no longer a reason for a separate ext4_sb.h header file, so
move it into ext4.h just to make life easier for developers to find
the relevant data structures and typedefs.  Should also speed up
compiles slightly, too.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-03 16:33:44 -04:00
Theodore Ts'o d444c3c381 ext4: Move the ext4_i.h header file into ext4.h
There is no longer a reason for a separate ext4_i.h header file, so
move it into ext4.h just to make life easier for developers to find
the relevant data structures and typedefs.  Should also speed up
compiles slightly, too.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01 13:44:33 -04:00
Theodore Ts'o 75507efb13 ext4: Don't avoid using BLOCK_UNINIT block groups in mballoc
By avoiding the use of not-yet-used block groups (i.e., block groups
with the BLOCK_UNINIT flag), mballoc had a tendency to create large
files with large non-contiguous gaps.  In addition avoiding the use of
new block groups had a tendency to push regular file data into the
first block group in a flex_bg group, which slows down the speed of
e2fsck pass 2, since it has a tendency to seek much more.  For
example:

               Before Patch                       After Patch
              Time in seconds                   Time in seconds
            Real /  User/  Sys   MB/s      Real /  User/  Sys    MB/s
Pass 1      8.52 / 2.21 / 0.46  20.43      8.84 / 4.97 / 1.11   19.68
Pass 2     21.16 / 1.02 / 1.86  11.30      6.54 / 1.77 / 1.78   36.39
Pass 3      0.01 / 0.00 / 0.00 139.00      0.01 / 0.01 / 0.00  128.90
Pass 4      0.16 / 0.15 / 0.00   0.00      0.17 / 0.17 / 0.00    0.00
Pass 5      2.52 / 1.99 / 0.09   0.79      2.31 / 1.78 / 0.06    0.86
Total      32.40 / 5.11 / 2.49  12.81     17.99 / 8.75 / 2.98   23.01

This was on a sample 80 gig root filesystem which was approximately
50% full.  Note the improved e2fsck pass 2 performance, by over a
factor of 3, due to a decreased number of seeks.  (The total amount of
I/O in pass 2 was unchanged; the layout of the directory blocks was
simply much better from e2fsck's's perspective.)

Other changes as a result of this patch on this sample filesystem:

                             Before Patch    After Patch
# of non-contig files           762             779
# of non-contig directories     571             570
# of BLOCK_UNINIT bg's          307             293
# of INODE_UNINIT bg's          503             503

Out of 640 block groups, of which 333 were in use, this patch caused
an extra 14 block groups to be utilized.  The number of non-contiguous
files did go up slightly, but when measured against the 99.9% of the
files (603,154) which were contiguously allocated, this is pretty
insignificant.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andreas Dilger <adilger@sun.com>
2009-05-01 12:58:36 -04:00
Theodore Ts'o 8b0f9e8f78 ext4: avoid unnecessary spinlock in critical POSIX ACL path
If a filesystem supports POSIX ACL's, the VFS layer expects the filesystem
to do POSIX ACL checks on any files not owned by the caller, and it does
this for every single pathname component that it looks up.

That obviously can be pretty expensive if the filesystem isn't careful
about it, especially with locking. That's doubly sad, since the common
case tends to be that there are no ACL's associated with the files in
question.

ext4 already caches the ACL data so that it doesn't have to look it up
over and over again, but it does so by taking the inode->i_lock spinlock
on every lookup. Which is a noticeable overhead even if it's a private
lock, especially on CPU's where the serialization is expensive (eg Intel
Netburst aka 'P4').

For the special case of not actually having any ACL's, all that locking is
unnecessary. Even if somebody else were to be changing the ACL's on
another CPU, we simply don't care - if we've seen a NULL ACL, we might as
well use it.

So just load the ACL speculatively without any locking, and if it was
NULL, just use it. If it's non-NULL (either because we had a cached
entry, or because the cache hasn't been filled in at all), it means that
we'll need to get the lock and re-load it properly.

(This commit was ported from a patch originally authored by Linus for
ext3.)

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-27 17:33:23 -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
Aneesh Kumar K.V 29fa89d088 ext4: Mark the unwritten buffer_head as mapped during write_begin
Setting BH_Unwritten buffer_heads as BH_Mapped avoids multiple
(unnecessary) calls to get_block() during the call to the write(2)
system call.  Setting BH_Unwritten buffer heads as BH_Mapped requires
that the writepages() functions can handle BH_Unwritten buffer_heads.

After this commit, things work as follows:

ext4_ext_get_block() returns unmapped, unwritten, buffer head when
called with create = 0 for prealloc space. This makes sure we handle
the read path and non-delayed allocation case correctly.  Even though
the buffer head is marked unmapped we have valid b_blocknr and b_bdev
values in the buffer_head.

ext4_da_get_block_prep() called for block resrevation will now return
mapped, unwritten, new buffer_head for prealloc space. This avoids
multiple calls to get_block() for write to same offset. By making such
buffers as BH_New, we also assure that sub-block zeroing of buffered
writes happens correctly.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-12 16:30:27 -04:00
Aneesh Kumar K.V 79ffab3439 ext4: Properly initialize the buffer_head state
These struct buffer_heads are allocated on the stack (and hence are
initialized with stack garbage).  They are only used to call a
get_blocks() function, so that's mostly OK, but b_state must be
initialized to be 0 so we don't have any unexpected BH_* flags set by
accident, such as BH_Unwritten or BH_Delay.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-13 15:13:42 -04:00
Theodore Ts'o c4b5a61431 ext4: Do not try to validate extents on special files
The EXTENTS_FL flag should never be set on special files, but if it
is, don't bother trying to validate that the extents tree is valid,
since only files, directories, and non-fast symlinks will ever have an
extent data structure.  We perhaps should flag the filesystem as being
corrupted if we see a special file (named pipes, device nodes, Unix
domain sockets, etc.) with the EXTENTS_FL flag, but e2fsck doesn't
currently check this case, so we'll just ignore this for now, since
it's harmless.

Without this fix, a special device with the extents flag is flagged as
an error by the kernel, so it is impossible to access or delete the
inode, but e2fsck doesn't see it as a problem, leading to
confused/frustrated users.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-24 18:45:35 -04:00
Theodore Ts'o a9e817425d ext4: Ignore i_file_acl_high unless EXT4_FEATURE_INCOMPAT_64BIT is present
Don't try to look at i_file_acl_high unless the INCOMPAT_64BIT feature
bit is set.  The field is normally zero, but older versions of e2fsck
didn't automatically check to make sure of this, so in the spirit of
"be liberal in what you accept", don't look at i_file_acl_high unless
we are using a 64-bit filesystem.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-24 16:11:18 -04:00
Theodore Ts'o 485c26ec70 ext4: Fix softlockup caused by illegal i_file_acl value in on-disk inode
If the block containing external extended attributes (which is stored
in i_file_acl and i_file_acl_high) is larger than the on-disk
filesystem, the process which tried to access the extended attributes
will endlessly issue kernel printks complaining that
"__find_get_block_slow() failed", locking up that CPU until the system
is forcibly rebooted.

So when we read in the inode, make sure the i_file_acl value is legal,
and if not, flag the filesystem as being corrupted.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-24 13:43:20 -04:00
Linus Torvalds a4277bf122 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:
  ext4: Fix potential inode allocation soft lockup in Orlov allocator
  ext4: Make the extent validity check more paranoid
  jbd: use SWRITE_SYNC_PLUG when writing synchronous revoke records
  jbd2: use SWRITE_SYNC_PLUG when writing synchronous revoke records
  ext4: really print the find_group_flex fallback warning only once
2009-04-24 08:37:40 -07:00
Theodore Ts'o b5451f7b26 ext4: Fix potential inode allocation soft lockup in Orlov allocator
If the Orlov allocator is having trouble finding an appropriate block
group, the fallback code could loop forever, causing a soft lockup
warning in find_group_orlov():

BUG: soft lockup - CPU#0 stuck for 61s! [cp:11728]
     ...
Pid: 11728, comm: cp Not tainted (2.6.30-rc1-dirty #77) Lenovo          
EIP: 0060:[<c021650e>] EFLAGS: 00000246 CPU: 0
EIP is at ext4_get_group_desc+0x54/0x9d
    ...
Call Trace:
 [<c0218021>] find_group_orlov+0x2ee/0x334
 [<c0120a5f>] ? sched_clock+0x8/0xb
 [<c02188e3>] ext4_new_inode+0x2cf/0xb1a

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-22 21:00:36 -04:00
Theodore Ts'o e84a26ce17 ext4: Make the extent validity check more paranoid
Instead of just checking that the extent block number is greater or
equal than s_first_data_block, make sure it it is not pointing into
the block group descriptors, since that is clearly wrong.  This helps
prevent filesystem from getting very badly corrupted in case an extent
block is corrupted.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-22 20:52:25 -04:00
Nikanth Karthikesan 226e7dabf5 ext4: Remove code handling bio_alloc failure with __GFP_WAIT
Remove code handling bio_alloc failure with __GFP_WAIT.
GFP_NOIO implies __GFP_WAIT.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 12:10:13 +02:00
Chuck Ebbert 6b82f3cb2d ext4: really print the find_group_flex fallback warning only once
Missing braces caused the warning to print more than once.

Signed-Off-By: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-14 07:37:40 -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
Thiemo Nagel e44543b83b ext4: Fix off-by-one-error in ext4_valid_extent_idx()
Signed-off-by: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-04 23:30:44 -04:00
Thiemo Nagel f73953c065 ext4: Fix big-endian problem in __ext4_check_blockref()
Commit fe2c8191 introduced a regression on big-endian system, because
the checks to make sure block references in non-extent inodes are
valid failed to use le32_to_cpu().

Reported-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Tested-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2009-04-07 18:46:47 -04:00
Linus Torvalds 811158b147 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
  trivial: Update my email address
  trivial: NULL noise: drivers/mtd/tests/mtd_*test.c
  trivial: NULL noise: drivers/media/dvb/frontends/drx397xD_fw.h
  trivial: Fix misspelling of "Celsius".
  trivial: remove unused variable 'path' in alloc_file()
  trivial: fix a pdlfush -> pdflush typo in comment
  trivial: jbd header comment typo fix for JBD_PARANOID_IOFAIL
  trivial: wusb: Storage class should be before const qualifier
  trivial: drivers/char/bsr.c: Storage class should be before const qualifier
  trivial: h8300: Storage class should be before const qualifier
  trivial: fix where cgroup documentation is not correctly referred to
  trivial: Give the right path in Documentation example
  trivial: MTD: remove EOL from MODULE_DESCRIPTION
  trivial: Fix typo in bio_split()'s documentation
  trivial: PWM: fix of #endif comment
  trivial: fix typos/grammar errors in Kconfig texts
  trivial: Fix misspelling of firmware
  trivial: cgroups: documentation typo and spelling corrections
  trivial: Update contact info for Jochen Hein
  trivial: fix typo "resgister" -> "register"
  ...
2009-04-03 15:24:35 -07:00
Linus Torvalds 8fe74cf053 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  Remove two unneeded exports and make two symbols static in fs/mpage.c
  Cleanup after commit 585d3bc06f
  Trim includes of fdtable.h
  Don't crap into descriptor table in binfmt_som
  Trim includes in binfmt_elf
  Don't mess with descriptor table in load_elf_binary()
  Get rid of indirect include of fs_struct.h
  New helper - current_umask()
  check_unsafe_exec() doesn't care about signal handlers sharing
  New locking/refcounting for fs_struct
  Take fs_struct handling to new file (fs/fs_struct.c)
  Get rid of bumping fs_struct refcount in pivot_root(2)
  Kill unsharing fs_struct in __set_personality()
2009-04-02 21:09:10 -07:00
Linus Torvalds 395d73413c 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: (33 commits)
  ext4: Regularize mount options
  ext4: fix locking typo in mballoc which could cause soft lockup hangs
  ext4: fix typo which causes a memory leak on error path
  jbd2: Update locking coments
  ext4: Rename pa_linear to pa_type
  ext4: add checks of block references for non-extent inodes
  ext4: Check for an valid i_mode when reading the inode from disk
  ext4: Use WRITE_SYNC for commits which are caused by fsync()
  ext4: Add auto_da_alloc mount option
  ext4: Use struct flex_groups to calculate get_orlov_stats()
  ext4: Use atomic_t's in struct flex_groups
  ext4: remove /proc tuning knobs
  ext4: Add sysfs support
  ext4: Track lifetime disk writes
  ext4: Fix discard of inode prealloc space with delayed allocation.
  ext4: Automatically allocate delay allocated blocks on rename
  ext4: Automatically allocate delay allocated blocks on close
  ext4: add EXT4_IOC_ALLOC_DA_BLKS ioctl
  ext4: Simplify delalloc code by removing mpage_da_writepages()
  ext4: Save stack space by removing fake buffer heads
  ...
2009-04-01 10:57:49 -07:00
Nick Piggin c2ec175c39 mm: page_mkwrite change prototype to match fault
Change the page_mkwrite prototype to take a struct vm_fault, and return
VM_FAULT_xxx flags.  There should be no functional change.

This makes it possible to return much more detailed error information to
the VM (and also can provide more information eg.  virtual_address to the
driver, which might be important in some special cases).

This is required for a subsequent fix.  And will also make it easier to
merge page_mkwrite() with fault() in future.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Artem Bityutskiy <dedekind@infradead.org>
Cc: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:14 -07:00
Al Viro ce3b0f8d5c New helper - current_umask()
current->fs->umask is what most of fs_struct users are doing.
Put that into a helper function.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31 23:00:26 -04:00
Matt LaPlante 692105b8ac trivial: fix typos/grammar errors in Kconfig texts
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-03-30 15:22:01 +02:00
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 e7c9e3e99a ext4: fix locking typo in mballoc which could cause soft lockup hangs
Smatch (http://repo.or.cz/w/smatch.git/) complains about the locking in
ext4_mb_add_n_trim() from fs/ext4/mballoc.c

  4438          list_for_each_entry_rcu(tmp_pa, &lg->lg_prealloc_list[order],
  4439                                                  pa_inode_list) {
  4440                  spin_lock(&tmp_pa->pa_lock);
  4441                  if (tmp_pa->pa_deleted) {
  4442                          spin_unlock(&pa->pa_lock);
  4443                          continue;
  4444                  }

Brown paper bag time...

Reported-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2009-03-27 19:43:21 -04:00
Dan Carpenter a7b19448dd ext4: fix typo which causes a memory leak on error path
This was found by smatch (http://repo.or.cz/w/smatch.git/)

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2009-03-27 19:42:54 -04:00
Aneesh Kumar K.V cc0fb9ad7d ext4: Rename pa_linear to pa_type
Impact: code cleanup

This patch rename pa_linear to pa_type and add MB_INODE_PA
and MB_GROUP_PA to indicate inode and group prealloc space.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-27 17:16:58 -04:00
Thiemo Nagel fe2c8191fa ext4: add checks of block references for non-extent inodes
Check block references in the inode and indorect blocks for non-extent
inodes to make sure they are valid, and flag an error if they are
invalid.

Signed-off-by: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-31 08:36:10 -04:00
Theodore Ts'o 563bdd61fe ext4: Check for an valid i_mode when reading the inode from disk
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-26 00:06:19 -04:00
Jan Kara a269eb1829 ext4: Use lowercase names of quota functions
Use lowercase names of quota functions instead of old uppercase ones.

Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Mingming Cao <cmm@us.ibm.com>
CC: linux-ext4@vger.kernel.org
2009-03-26 02:18:36 +01:00
Mingming Cao 60e58e0f30 ext4: quota reservation for delayed allocation
Uses quota reservation/claim/release to handle quota properly for delayed
allocation in the three steps: 1) quotas are reserved when data being copied
to cache when block allocation is defered 2) when new blocks are allocated.
reserved quotas are converted to the real allocated quota, 2) over-booked
quotas for metadata blocks are released back.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
2009-03-26 02:18:34 +01:00
Jan Kara edf7245362 ext4: Remove unnecessary quota functions
ext4_dquot_initialize() and ext4_dquot_drop() is no longer
needed because of modified quota locking.

Signed-off-by: Jan Kara <jack@suse.cz>
2009-03-26 02:18:34 +01:00
Eric Sandeen d33a1976fb ext4: fix bb_prealloc_list corruption due to wrong group locking
This is for Red Hat bug 490026: EXT4 panic, list corruption in
ext4_mb_new_inode_pa

ext4_lock_group(sb, group) is supposed to protect this list for
each group, and a common code flow to remove an album is like
this:

    ext4_get_group_no_and_offset(sb, pa->pa_pstart, &grp, NULL);
    ext4_lock_group(sb, grp);
    list_del(&pa->pa_group_list);
    ext4_unlock_group(sb, grp);

so it's critical that we get the right group number back for
this prealloc context, to lock the right group (the one 
associated with this pa) and prevent concurrent list manipulation.

however, ext4_mb_put_pa() passes in (pa->pa_pstart - 1) with a 
comment, "-1 is to protect from crossing allocation group".

This makes sense for the group_pa, where pa_pstart is advanced
by the length which has been used (in ext4_mb_release_context()),
and when the entire length has been used, pa_pstart has been
advanced to the first block of the next group.

However, for inode_pa, pa_pstart is never advanced; it's just
set once to the first block in the group and not moved after
that.  So in this case, if we subtract one in ext4_mb_put_pa(),
we are actually locking the *previous* group, and opening the
race with the other threads which do not subtract off the extra
block.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-16 23:25:40 -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
Eric Sandeen 8d03c7a0c5 ext4: fix bogus BUG_ONs in in mballoc code
Thiemo Nagel reported that:

# dd if=/dev/zero of=image.ext4 bs=1M count=2
# mkfs.ext4 -v -F -b 1024 -m 0 -g 512 -G 4 -I 128 -N 1 \
  -O large_file,dir_index,flex_bg,extent,sparse_super image.ext4
# mount -o loop image.ext4 mnt/
# dd if=/dev/zero of=mnt/file

oopsed, with a BUG_ON in ext4_mb_normalize_request because
size == EXT4_BLOCKS_PER_GROUP

It appears to me (esp. after talking to Andreas) that the BUG_ON
is bogus; a request of exactly EXT4_BLOCKS_PER_GROUP should
be allowed, though larger sizes do indicate a problem.

Fix that an another (apparently rare) codepath with a similar check.

Reported-by: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-14 11:51:46 -04:00
Theodore Ts'o 2842c3b544 ext4: Print the find_group_flex() warning only once
This is a short-term warning, and even printk_ratelimit() can result
in too much noise in system logs.  So only print it once as a warning.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-12 12:20:01 -04:00
Eric Sandeen 395a87bfef ext4: fix header check in ext4_ext_search_right() for deep extent trees.
The ext4_ext_search_right() function is confusing; it uses a
"depth" variable which is 0 at the root and maximum at the leaves, 
but the on-disk metadata uses a "depth" (actually eh_depth) which
is opposite: maximum at the root, and 0 at the leaves.

The ext4_ext_check_header() function is given a depth and checks
the header agaisnt that depth; it expects the on-disk semantics,
but we are giving it the opposite in the while loop in this 
function.  We should be giving it the on-disk notion of "depth"
which we can get from (p_depth - depth) - and if you look, the last
(more commonly hit) call to ext4_ext_check_header() does just this.

Sending in the wrong depth results in (incorrect) messages
about corruption:

EXT4-fs error (device sdb1): ext4_ext_search_right: bad header
in inode #2621457: unexpected eh_depth - magic f30a, entries 340,
max 340(0), depth 1(2)

http://bugzilla.kernel.org/show_bug.cgi?id=12821

Reported-by: David Dindorp <ddi@dubex.dk>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-10 18:18:47 -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
Eric Sandeen 7ce9d5d1f3 ext4: fix ext4_free_inode() vs. ext4_claim_inode() race
I was seeing fsck errors on inode bitmaps after a 4 thread
dbench run on a 4 cpu machine:

Inode bitmap differences: -50736 -(50752--50753) etc...

I believe that this is because ext4_free_inode() uses atomic
bitops, and although ext4_new_inode() *used* to also use atomic 
bitops for synchronization, commit 
393418676a changed this to use
the sb_bgl_lock, so that we could also synchronize against
read_inode_bitmap and initialization of uninit inode tables.

However, that change left ext4_free_inode using atomic bitops,
which I think leaves no synchronization between setting & 
unsetting bits in the inode table.

The below patch fixes it for me, although I wonder if we're 
getting at all heavy-handed with this spinlock...

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-04 18:38:18 -05:00
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
Aneesh Kumar K.V d6014301b5 ext4: Fix discard of inode prealloc space with delayed allocation.
With delayed allocation we should not/cannot discard inode prealloc
space during file close. We would still have dirty pages for which we
haven't allocated blocks yet. With this fix after each get_blocks
request we check whether we have zero reserved blocks and if yes and
we don't have any writers on the file we discard inode prealloc space.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-27 22:36:43 -04:00
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
Theodore Ts'o 8b1a8ff8b3 ext4: Remove duplicate call to ext4_commit_super() in ext4_freeze()
Commit c4be0c1d added error checking to ext4_freeze() when calling
ext4_commit_super().  Unfortunately the patch failed to remove the
original call to ext4_commit_super(), with the net result that when
freezing the filesystem, the superblock gets written twice, the first
time without error checking.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-28 00:08:53 -05:00
Theodore Ts'o 8750c6d5fc ext4: Automatically allocate delay allocated blocks on rename
When renaming a file such that a link to another inode is overwritten,
force any delay allocated blocks that to be allocated so that if the
filesystem is mounted with data=ordered, the data blocks will be
pushed out to disk along with the journal commit.  Many application
programs expect this, so we do this to avoid zero length files if the
system crashes unexpectedly.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23 23:05:27 -05:00
Theodore Ts'o 7d8f9f7d15 ext4: Automatically allocate delay allocated blocks on close
When closing a file that had been previously truncated, force any
delay allocated blocks that to be allocated so that if the filesystem
is mounted with data=ordered, the data blocks will be pushed out to
disk along with the journal commit.  Many application programs expect
this, so we do this to avoid zero length files if the system crashes
unexpectedly.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-24 08:21:14 -05:00
Theodore Ts'o ccd2506bd4 ext4: add EXT4_IOC_ALLOC_DA_BLKS ioctl
Add an ioctl which forces all of the delay allocated blocks to be
allocated.  This also provides a function ext4_alloc_da_blocks() which
will be used by the following commits to force files to be fully
allocated to preserve application-expected ext3 behaviour.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-26 01:04:07 -05:00
Theodore Ts'o f63e6005bc ext4: Simplify delalloc code by removing mpage_da_writepages()
The mpage_da_writepages() function is only used in one place, so
inline it to simplify the call stack and make the code easier to
understand.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23 16:42:39 -05:00
Theodore Ts'o 8dc207c0e7 ext4: Save stack space by removing fake buffer heads
Struct mpage_da_data and mpage_add_bh_to_extent() use a fake struct
buffer_head which is 104 bytes on an x86_64 system, but only use 24
bytes of the structure.  On systems that use a spinlock for atomic_t,
the stack savings will be even greater.

It turns out that using a fake struct buffer_head doesn't even save
that much code, and it makes the code more confusing since it's not
used as a "real" buffer head.  So just store pass b_size and b_state
in mpage_add_bh_to_extent(), and store b_size, b_state, and b_block_nr
in the mpage_da_data structure.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23 06:46:01 -05:00
Theodore Ts'o ed5bde0bf8 ext4: Simplify delalloc implementation by removing mpd.get_block
This parameter was always set to ext4_da_get_block_write().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23 10:48:07 -05:00
Aneesh Kumar K.V 7a262f7c69 ext4: Validate extent details only when read from the disk
Make sure we validate extent details only when read from the disk.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-27 16:39:58 -04:00
Aneesh Kumar K.V 56b19868ac ext4: Add checks to validate extent entries.
This patch adds checks to validate the extent entries along with extent
headers, to avoid crashes caused by corrupt filesystems.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-12 09:51:20 -04:00
Bryan Donlan e6f009b0b4 ext4: return -EIO not -ESTALE on directory traversal through deleted inode
ext4_iget() returns -ESTALE if invoked on a deleted inode, in order to
report errors to NFS properly.  However, in ext4_lookup(), this
-ESTALE can be propagated to userspace if the filesystem is corrupted
such that a directory entry references a deleted inode.  This leads to
a misleading error message - "Stale NFS file handle" - and confusion
on the part of the admin.

The bug can be easily reproduced by creating a new filesystem, making
a link to an unused inode using debugfs, then mounting and attempting
to ls -l said link.

This patch thus changes ext4_lookup to return -EIO if it receives
-ESTALE from ext4_iget(), as ext4 does for other filesystem metadata
corruption; and also invokes the appropriate ext*_error functions when
this case is detected.

Signed-off-by: Bryan Donlan <bdonlan@gmail.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-22 21:20:25 -05:00
Theodore Ts'o a4912123b6 ext4: New inode/block allocation algorithms for flex_bg filesystems
The find_group_flex() inode allocator is now only used if the
filesystem is mounted using the "oldalloc" mount option.  It is
replaced with the original Orlov allocator that has been updated for
flex_bg filesystems (it should behave the same way if flex_bg is
disabled).  The inode allocator now functions by taking into account
each flex_bg group, instead of each block group, when deciding whether
or not it's time to allocate a new directory into a fresh flex_bg.

The block allocator has also been changed so that the first block
group in each flex_bg is preferred for use for storing directory
blocks.  This keeps directory blocks close together, which is good for
speeding up e2fsck since large directories are more likely to look
like this:

debugfs:  stat /home/tytso/Maildir/cur
Inode: 1844562   Type: directory    Mode:  0700   Flags: 0x81000
Generation: 1132745781    Version: 0x00000000:0000ad71
User: 15806   Group: 15806   Size: 1060864
File ACL: 0    Directory ACL: 0
Links: 2   Blockcount: 2072
Fragment:  Address: 0    Number: 0    Size: 0
 ctime: 0x499c0ff4:164961f4 -- Wed Feb 18 08:41:08 2009
 atime: 0x499c0ff4:00000000 -- Wed Feb 18 08:41:08 2009
 mtime: 0x49957f51:00000000 -- Fri Feb 13 09:10:25 2009
crtime: 0x499c0f57:00d51440 -- Wed Feb 18 08:38:31 2009
Size of extra inode fields: 28
BLOCKS:
(0):7348651, (1-258):7348654-7348911
TOTAL: 259

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-12 12:18:34 -04:00
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
Theodore Ts'o 05bf9e839d ext4: Add fallback for find_group_flex
This is a workaround for find_group_flex() which badly needs to be
replaced.  One of its problems (besides ignoring the Orlov algorithm)
is that it is a bit hyperactive about returning failure under
suspicious circumstances.  This can lead to spurious ENOSPC failures
even when there are inodes still available.

Work around this for now by retrying the search using
find_group_other() if find_group_flex() returns -1.  If
find_group_other() succeeds when find_group_flex() has failed, log a
warning message.

A better block/inode allocator that will fix this problem for real has
been queued up for the next merge window.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-21 12:13:24 -05:00
Dan Carpenter 090542641d ext4: Fix NULL dereference in ext4_ext_migrate()'s error handling
This was found through a code checker (http://repo.or.cz/w/smatch.git/). 
It looks like you might be able to trigger the error by trying to migrate 
a readonly file system.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-15 20:02:19 -05:00
Duane Griffin 2dc6b0d48c ext4: tighten restrictions on inode flags
At the moment there are few restrictions on which flags may be set on
which inodes.  Specifically DIRSYNC may only be set on directories and
IMMUTABLE and APPEND may not be set on links.  Tighten that to disallow
TOPDIR being set on non-directories and only NODUMP and NOATIME to be set
on non-regular file, non-directories.

Introduces a flags masking function which masks flags based on mode and
use it during inode creation and when flags are set via the ioctl to
facilitate future consistency.

Signed-off-by: Duane Griffin <duaneg@dghda.com>
Acked-by: Andreas Dilger <adilger@sun.com>
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 18:09:20 -05:00
Duane Griffin 8fa43a81b9 ext4: don't inherit inappropriate inode flags from parent
At present INDEX and EXTENTS are the only flags that new ext4 inodes do
NOT inherit from their parent.  In addition prevent the flags DIRTY,
ECOMPR, IMAGIC, TOPDIR, HUGE_FILE and EXT_MIGRATE from being inherited. 
List inheritable flags explicitly to prevent future flags from
accidentally being inherited.

This fixes the TOPDIR flag inheritance bug reported at
http://bugzilla.kernel.org/show_bug.cgi?id=9866.

Signed-off-by: Duane Griffin <duaneg@dghda.com>
Acked-by: Andreas Dilger <adilger@sun.com>
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 18:57:26 -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
Wei Yongjun 3d0518f475 ext4: New rec_len encoding for very large blocksizes
The rec_len field in the directory entry is 16 bits, so to encode
blocksizes larger than 64k becomes problematic.  This patch allows us
to supprot block sizes up to 256k, by using the low 2 bits to extend
the range of rec_len to 2**18-1 (since valid rec_len sizes must be a
multiple of 4).  We use the convention that a rec_len of 0 or 65535
means the filesystem block size, for compatibility with older kernels.

It's unlikely we'll see VM pages of up to 256k, but at some point we
might find that the Linux VM has been enhanced to support filesystem
block sizes > than the VM page size, at which point it might be useful
for some applications to allow very large filesystem block sizes.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-14 23:01:36 -05:00
Theodore Ts'o 8bad4597c2 ext4: Use unsigned int for blocksize in dx_make_map() and dx_pack_dirents()
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-14 21:46:54 -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
Aneesh Kumar K.V d794bf8e09 ext4: Initialize preallocation list_head's properly
When creating a new ext4_prealloc_space structure, we have to
initialize its list_head pointers before we add them to any prealloc
lists.  Otherwise, with list debug enabled, we will get list
corruption warnings.

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 10:31:16 -05:00
Aneesh Kumar K.V ba4439165f ext4: Fix lockdep warning
We should not call ext4_mb_add_n_trim while holding alloc_semp.

    =============================================
    [ INFO: possible recursive locking detected ]
    2.6.29-rc4-git1-dirty #124
    ---------------------------------------------
    ffsb/3116 is trying to acquire lock:
     (&meta_group_info[i]->alloc_sem){----}, at: [<ffffffff8035a6e8>]
     ext4_mb_load_buddy+0xd2/0x343

    but task is already holding lock:
     (&meta_group_info[i]->alloc_sem){----}, at: [<ffffffff8035a6e8>]
     ext4_mb_load_buddy+0xd2/0x343

http://bugzilla.kernel.org/show_bug.cgi?id=12672

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-10 11:14:34 -05:00