We need to make sure we update the inode bitmap and clear
EXT4_BG_INODE_UNINIT flag with sb_bgl_lock held, since
ext4_read_inode_bitmap() looks at EXT4_BG_INODE_UNINIT to decide
whether to initialize the inode bitmap each time it is called.
(introduced by commit c806e68f.)
ext4_read_inode_bitmap does:
spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
ext4_init_inode_bitmap(sb, bh, block_group, desc);
and ext4_new_inode does
if (!ext4_set_bit_atomic(sb_bgl_lock(sbi, group),
ino, inode_bitmap_bh->b_data))
......
...
spin_lock(sb_bgl_lock(sbi, group));
gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
i.e., on allocation we update the bitmap then we take the sb_bgl_lock
and clear the EXT4_BG_INODE_UNINIT flag. What can happen is a
parallel ext4_read_inode_bitmap can zero out the bitmap in between
the above ext4_set_bit_atomic and spin_lock(sb_bg_lock..)
The race results in below user visible errors
EXT4-fs error (device sdb1): ext4_free_inode: bit already cleared for inode 168449
EXT4-fs warning (device sdb1): ext4_unlink: Deleting nonexistent file ...
EXT4-fs warning (device sdb1): ext4_rmdir: empty directory has too many links ...
# ls -al /mnt/tmp/f/p369/d3/d6/d39/db2/dee/d10f/d3f/l71
ls: /mnt/tmp/f/p369/d3/d6/d39/db2/dee/d10f/d3f/l71: Stale NFS file handle
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
Rename some variables. We also unlock locks in the reverse order we
acquired as a part of cleanup.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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>
We need to make sure we update the block bitmap and clear
EXT4_BG_BLOCK_UNINIT flag with sb_bgl_lock held, since
ext4_read_block_bitmap() looks at EXT4_BG_BLOCK_UNINIT to decide
whether to initialize the block bitmap each time it is called
(introduced by commit c806e68f), and this can race with block
allocations in ext4_mb_mark_diskspace_used().
ext4_read_block_bitmap does:
spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
ext4_init_block_bitmap(sb, bh, block_group, desc);
Now on the block allocation side we do
mb_set_bits(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group), bitmap_bh->b_data,
ac->ac_b_ex.fe_start, ac->ac_b_ex.fe_len);
....
spin_lock(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group));
if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
ie on allocation we update the bitmap then we take the sb_bgl_lock
and clear the EXT4_BG_BLOCK_UNINIT flag. What can happen is a
parallel ext4_read_block_bitmap can zero out the bitmap in between
the above mb_set_bits and spin_lock(sb_bg_lock..)
The race results in below user visible errors
EXT4-fs error (device sdb1): ext4_mb_release_inode_pa: free 100, pa_free 105
EXT4-fs error (device sdb1): mb_free_blocks: double-free of inode 0's block ..
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
The mballoc code likes to call ext4_error while it is holding locked
block groups. This can causes a scheduling in atomic context BUG. We
can't just unlock the block group and relock it after/if ext4_error
returns since that might result in race conditions in the case where
the filesystem is set to continue after finding errors.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_mb_init_group(), if the filesystem block size is less than
PAGE_SIZE/2, the code tries to grab alloc_sem for multiple block
groups in a loop. We need to allow for this by using
down_write_nested() and passing in the loop index as a lock subclass
number. This works because no other code path needs to take multiple
alloc_sem's. Note that lockdep will fail for filesystem blocksize
smaller than to PAGE_SIZE/16k. (e.g., a 1k filesystem blocksize with
a 32k page size, or a 2k filesystem blocksize with a 64k blocksize,
etc.)
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When we generate buddy cache (especially during resize) we need to
make sure we don't use the blocks freed but not yet comitted. This
makes sure we have the right value of free blocks count in the group
info and also in the bitmap. This also ensures the ordered mode
consistency
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
Move some of the forward declaration of the static functions
to mballoc.c where they are used. This enables us to include
mballoc.h in other .c files. Also correct the buddy cache
documentation.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The new groups added during resize are flagged as
need_init group. Make sure we properly initialize these
groups. When we have block size < page size and we are adding
new groups the page may still be marked uptodate even though
we haven't initialized the group. While forcing the init
of buddy cache we need to make sure other groups part of the
same page of buddy cache is not using the cache.
group_info->alloc_sem is added to ensure the same.
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
With this change new blocks added during resize
are marked as free in the block bitmap and the
group is flagged with EXT4_GROUP_INFO_NEED_INIT_BIT
flag. This makes sure when mballoc tries to allocate
blocks from the new group we would reload the
buddy information using the bitmap present in the disk.
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
* 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>
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>
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>
The i_ext_generation was incremented, but never used. Remove it to
slim down the ext4_inode_info structure.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add new mount options, min_batch_time and max_batch_time, which
controls how long the jbd2 layer should wait for additional filesystem
operations to get batched with a synchronous write transaction.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We can call ext4_mb_check_limits even after successfully allocating
the requested blocks. In that case, make sure we don't overwrite
ac_status if it already has the status AC_STATUS_FOUND. This fixes
the lockdep warning:
=============================================
[ INFO: possible recursive locking detected ]
2.6.28-rc6-autokern1 #1
---------------------------------------------
fsstress/11948 is trying to acquire lock:
(&meta_group_info[i]->alloc_sem){----}, at: [<c04d9a49>] ext4_mb_load_buddy+0x9f/0x278
.....
stack backtrace:
.....
[<c04db974>] ext4_mb_regular_allocator+0xbb5/0xd44
.....
but task is already holding lock:
(&meta_group_info[i]->alloc_sem){----}, at: [<c04d9a49>] ext4_mb_load_buddy+0x9f/0x278
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
This removes annoying blank syslog entries emitted by ext4_error() or
ext4_warning(), since these functions add their own newline.
Signed-off-by: Nick Warne <nick@ukfsn.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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>
I chased the cause of following ext4 oops report which is tested on
ia64 box.
http://bugzilla.kernel.org/show_bug.cgi?id=12018
The cause is the size of s_mb_maxs array that is defined as "unsigned
short" in ext4_sb_info structure. If the file system's block size is
8k or greater, an unsigned short is not wide enough to contain the
value fs->blocksize << 3.
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: stable@kernel.org
The inode table has been zeroed in setup_new_group_blocks(). Mark it as
such in ext4_group_add(). Since we are currently clearing inode table
for the new block group, we should set the EXT4_BG_INODE_ZEROED flag.
If at some point in the future we don't immediately zero out the inode
table as part of the resize operation, then obviously we shouldn't do
this.
Signed-off-by: Solofo.Ramangalahy@bull.net
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Remove some completely unneeded code which which caused an ext4_error
to be generated when mounting a file system with only a single block
group.
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
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
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>
The convenience function do_blk_alloc() is a static function with only
one caller, so fold it into ext4_new_meta_blocks() to simplify the
code and to make it easier to understand.
To save more stack space, if count is a null pointer in
ext4_new_meta_blocks() assume that caller wanted a single block (and
if there is an error, no blocks were allocated).
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
There were only two one callers of the function ext4_new_meta_block(),
which just a very simpler wrapper function around
ext4_new_meta_blocks(). Change those two functions to call
ext4_new_meta_blocks() directly, to save code and stack space usage.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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>
This fixes a gcc warning but it doesn't appear able to result in a
failure, since the primary way the loop is exited is the first
conditional in the for loop, and at least for a consistent filesystem,
the signed/unsigned should in practice never be exposed.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The original ext3 hash algorithms assumed that variables of type char
were signed, as God and K&R intended. Unfortunately, this assumption
is not true on some architectures. Userspace support for marking
filesystems with non-native signed/unsigned chars was added two years
ago, but the kernel-side support was never added (until now).
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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>
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>
As suggested by Andreas Dilger, introduce a bgl_lock_ptr() helper in
<linux/blockgroup_lock.h> and add separate sb_bgl_lock() helpers to
filesystem specific header files to break the hidden dependency to
struct ext[234]_sb_info.
Also, while at it, convert the macros to static inlines to try make up
for all the times I broke Andrew Morton's tree.
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: Linus Torvalds <torvalds@linux-foundation.org>
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>
We have two seperate config entries for large devices/files. One
is CONFIG_LBD that guards just the devices, the other is CONFIG_LSF
that handles large files. This doesn't make a lot of sense, you typically
want both or none. So get rid of CONFIG_LSF and change CONFIG_LBD wording
to indicate that it covers both.
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Revert
commit e8ced39d5e
Author: Mingming Cao <cmm@us.ibm.com>
Date: Fri Jul 11 19:27:31 2008 -0400
percpu_counter: new function percpu_counter_sum_and_set
As described in
revert "percpu counter: clean up percpu_counter_sum_and_set()"
the new percpu_counter_sum_and_set() is racy against updates to the
cpu-local accumulators on other CPUs. Revert that change.
This means that ext4 will be slow again. But correct.
Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: <stable@kernel.org> [2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert
commit 1f7c14c62c
Author: Mingming Cao <cmm@us.ibm.com>
Date: Thu Oct 9 12:50:59 2008 -0400
percpu counter: clean up percpu_counter_sum_and_set()
Before this patch we had the following:
percpu_counter_sum(): return the percpu_counter's value
percpu_counter_sum_and_set(): return the percpu_counter's value, copying
that value into the central value and zeroing the per-cpu counters before
returning.
After this patch, percpu_counter_sum_and_set() has gone, and
percpu_counter_sum() gets the old percpu_counter_sum_and_set()
functionality.
Problem is, as Eric points out, the old percpu_counter_sum_and_set()
functionality was racy and wrong. It zeroes out counters on "other" cpus,
without holding any locks which will prevent races agaist updates from
those other CPUS.
This patch reverts 1f7c14c62c. This means
that percpu_counter_sum_and_set() still has the race, but
percpu_counter_sum() does not.
Note that this is not a simple revert - ext4 has since started using
percpu_counter_sum() for its dirty_blocks counter as well.
Note that this revert patch changes percpu_counter_sum() semantics.
Before the patch, a call to percpu_counter_sum() will bring the counter's
central counter mostly up-to-date, so a following percpu_counter_read()
will return a close value.
After this patch, a call to percpu_counter_sum() will leave the counter's
central accumulator unaltered, so a subsequent call to
percpu_counter_read() can now return a significantly inaccurate result.
If there is any code in the tree which was introduced after
e8ced39d5e was merged, and which depends
upon the new percpu_counter_sum() semantics, that code will break.
Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Conflicts:
security/keys/internal.h
security/keys/process_keys.c
security/keys/request_key.c
Fixed conflicts above by using the non 'tsk' versions.
Signed-off-by: James Morris <jmorris@namei.org>
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.
Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: adilger@sun.com
Cc: linux-ext4@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
When initializing an uninitialized block group in ext4_new_inode(),
its block group checksum must be re-calculated. This fixes a race
when several threads try to allocate a new inode in an UNINIT'd group.
There is some question whether we need to be initializing the block
bitmap in ext4_new_inode() at all, but for now, if we are going to
init the block group, let's eliminate the race.
Signed-off-by: Frederic Bohe <frederic.bohe@bull.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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>
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>
In ext4_sync_fs, we only wait for a commit to finish if we started it,
but there may be one already in progress which will not be synced.
In the case of a data=ordered umount with pending long symlinks which
are delayed due to a long list of other I/O on the backing block
device, this causes the buffer associated with the long symlinks to
not be moved to the inode dirty list in the second phase of
fsync_super. Then, before they can be dirtied again, kjournald exits,
seeing the UMOUNT flag and the dirty pages are never written to the
backing block device, causing long symlink corruption and exposing new
or previously freed block data to userspace.
To ensure all commits are synced, we flush all journal commits now
when sync_fs'ing ext4.
Signed-off-by: Arthur Jones <ajones@riverbed.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Eric Sandeen <sandeen@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Use le16_to_cpu to read the s_reserved_gdt_blocks values
from super block.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If we try to free a block which is already freed, the code was
returning without first unlocking the group.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
As reported by Eric Paris, the capable() check in ext4_has_free_blocks()
sometimes causes SELinux denials.
We can rearrange the logic so that we only try to use the root-reserved
blocks when necessary, and even then we can move the capable() test
to last, to avoid the check most of the time.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Mingming pointed out that ext4_claim_free_blocks & ext4_has_free_blocks
are largely cut & pasted; they can be collapsed/merged as follows.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Vegard Nossum reported a bug which accesses freed memory (found via
kmemcheck). When journal has been aborted, ext4_put_super() calls
ext4_abort() after freeing the journal_t object, and then ext4_abort()
accesses it. This patch fix it.
Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Aneesh Kumar K.V