Revert e92a4d595b.
Dmitry points out
"When we block_prepare_write() failed while ext3_prepare_write() we jump to
"failure" label and call ext3_prepare_failure() witch search last mapped bh
and invoke commit_write untill it. This is wrong!! because some bh from
begining to the last mapped bh may be not uptodate. As a result we commit to
disk not uptodate page content witch contains garbage from previous usage."
and
"Unexpected file size increasing."
Call trace the same as it was in first issue but result is different.
For example we have file with i_size is zero. we want write two blocks ,
but fs has only one free block.
->ext3_prepare_write(...from == 0, to == 2048)
retry:
->block_prepare_write() == -ENOSPC# we failed but allocated one block here.
->ext3_prepare_failure()
->commit_write( from == 0, to == 1024) # after this i_size becomes 1024 :)
if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
goto retry;
Finally when all retries will be spended ext3_prepare_failure return
-ENOSPC, but i_size was increased and later block trimm procedures can't
help here.
We don't appear to have the horsepower to fix these issues, so let's put
things back the way they were for now.
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ken Chen <kenneth.w.chen@intel.com>
Cc: Andrey Savochkin <saw@sw.ru>
Cc: <linux-ext4@vger.kernel.org>
Cc: Dmitriy Monakhov <dmonakhov@openvz.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are race issues around ext[34] xattr block release code.
ext[34]_xattr_release_block() checks the reference count of xattr block
(h_refcount) and frees that xattr block if it is the last one reference it.
Unlike ext2, the check of this counter is unprotected by any lock.
ext[34]_xattr_release_block() will free the mb_cache entry before freeing
that xattr block. There is a small window between the check for the re
h_refcount ==1 and the call to mb_cache_entry_free(). During this small
window another inode might find this xattr block from the mbcache and reuse
it, racing a refcount updates. The xattr block will later be freed by the
first inode without notice other inode is still use it. Later if that
block is reallocated as a datablock for other file, then more serious
problem might happen.
We need put a lock around places checking the refount as well to avoid
racing issue. Another place need this kind of protection is in
ext3_xattr_block_set(), where it will modify the xattr block content in-
the-fly if the refcount is 1 (means it's the only inode reference it).
This will also fix another issue: the xattr block may not get freed at all
if no lock is to protect the refcount check at the release time. It is
possible that the last two inodes could release the shared xattr block at
the same time. But both of them think they are not the last one so only
decreased the h_refcount without freeing xattr block at all.
We need to call lock_buffer() after ext3_journal_get_write_access() to
avoid deadlock (because the later will call lock_buffer()/unlock_buffer
() as well).
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Cc: Andreas Gruenbacher <agruen@suse.de>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there. Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.
To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.
Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm. I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch is inspired by Arjan's "Patch series to mark struct
file_operations and struct inode_operations const".
Compile tested with gcc & sparse.
Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many struct inode_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Naming is confusing, ext3_inc_count manipulates i_nlink not i_count
- handle argument passed in is not used
- ext3 and ext4 already call inc_nlink and dec_nlink directly in other places
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Return -ENOENT from ext[34]_link if we've raced with unlink and i_nlink is
0. Doing otherwise has the potential to corrupt the orphan inode list,
because we'd wind up with an inode with a non-zero link count on the list,
and it will never get properly cleaned up & removed from the orphan list
before it is freed.
[akpm@osdl.org: build fix]
Signed-off-by: Eric Sandeen <sandeen@redhat.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>
Fix insecure default behaviour reported by Tigran Aivazian: if an ext2 or
ext3 or ext4 filesystem is tuned to mount with "acl", but mounted by a
kernel built without ACL support, then umask was ignored when creating
inodes - though root or user has umask 022, touch creates files as 0666,
and mkdir creates directories as 0777.
This appears to have worked right until 2.6.11, when a fix to the default
mode on symlinks (always 0777) assumed VFS applies umask: which it does,
unless the mount is marked for ACLs; but ext[234] set MS_POSIXACL in
s_flags according to s_mount_opt set according to def_mount_opts.
We could revert to the 2.6.10 ext[234]_init_acl (adding an S_ISLNK test);
but other filesystems only set MS_POSIXACL when ACLs are configured. We
could fix this at another level; but it seems most robust to avoid setting
the s_mount_opt flag in the first place (at the expense of more ifdefs).
Likewise don't set the XATTR_USER flag when built without XATTR support.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: <linux-ext4@vger.kernel.org>
Cc: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the rare case where we have skipped orphan inode processing due to a
readonly block device, and the block device subsequently changes back to
read-write, disallow a remount,rw transition of the filesystem when we have an
unprocessed orphan inodes as this would corrupt the list.
Ideally we should process the orphan inode list during the remount, but that's
trickier, and this plugs the hole for now.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: "Stephen C. Tweedie" <sct@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This facility provides three entry points:
ilog2() Log base 2 of unsigned long
ilog2_u32() Log base 2 of u32
ilog2_u64() Log base 2 of u64
These facilities can either be used inside functions on dynamic data:
int do_something(long q)
{
...;
y = ilog2(x)
...;
}
Or can be used to statically initialise global variables with constant values:
unsigned n = ilog2(27);
When performing static initialisation, the compiler will report "error:
initializer element is not constant" if asked to take a log of zero or of
something not reducible to a constant. They treat negative numbers as
unsigned.
When not dealing with a constant, they fall back to using fls() which permits
them to use arch-specific log calculation instructions - such as BSR on
x86/x86_64 or SCAN on FRV - if available.
[akpm@osdl.org: MMC fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Wojtek Kaniewski <wojtekka@toxygen.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in the ext3
filesystem.
Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Port fix to the off-by-one in find_next_usable_block's memscan from ext2 to
ext3; but it didn't cause a serious problem for ext3 because the additional
ext3_test_allocatable check rescued it from the error.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The reservations tree is an rb_tree not a list, so it's less confusing to use
rb_entry() than list_entry() - though they're both just container_of().
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ext3_new_blocks should reset the reservation window size to 0 when squeezing
the last blocks out of an almost full filesystem, so the retry doesn't skip
any groups with less than half that free, reporting ENOSPC too soon.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If you do something like:
# touch foo
# tail -f foo &
# rm foo
# <take snapshot>
# <mount snapshot>
you'll panic, because ext3/4 tries to do orphan list processing on the
readonly snapshot device, and:
kernel: journal commit I/O error
kernel: Assertion failure in journal_flush_Rsmp_e2f189ce() at journal.c:1356: "!journal->j_checkpoint_transactions"
kernel: Kernel panic: Fatal exception
for a truly readonly underlying device, it's reasonable and necessary
to just skip orphan list processing.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Hugh Dickins wrote:
> Not found anything relevant, but I keep noticing these lines
> in ext2_try_to_allocate_with_rsv(), ext3 and ext4 similar:
>
> } else if (grp_goal > 0 &&
> (my_rsv->rsv_end - grp_goal + 1) < *count)
> try_to_extend_reservation(my_rsv, sb,
> *count-my_rsv->rsv_end + grp_goal - 1);
>
> They're wrong, a no-op in most groups, aren't they? rsv_end is an
> absolute block number, whereas grp_goal is group-relative, so the
> calculation ought to bring in group_first_block? Or I'm confused.
>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Cc: "linux-ext4@vger.kernel.org" <linux-ext4@vger.kernel.org>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In journal=ordered or journal=data mode retry in ext3_prepare_write()
breaks the requirements of journaling of data with respect to metadata.
The fix is to call commit_write to commit allocated zero blocks before
retry.
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ken Chen <kenneth.w.chen@intel.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I've been using Steve Grubb's purely evil "fsfuzzer" tool, at
http://people.redhat.com/sgrubb/files/fsfuzzer-0.4.tar.gz
Basically it makes a filesystem, splats some random bits over it, then
tries to mount it and do some simple filesystem actions.
At best, the filesystem catches the corruption gracefully. At worst,
things spin out of control.
As you might guess, we found a couple places in ext3 where things spin out
of control :)
First, we had a corrupted directory that was never checked for
consistency... it was corrupt, and pointed to another bad "entry" of
length 0. The for() loop looped forever, since the length of
ext3_next_entry(de) was 0, and we kept looking at the same pointer over and
over and over and over... I modeled this check and subsequent action on
what is done for other directory types in ext3_readdir...
(adding this check adds some computational expense; I am testing a followup
patch to reduce the number of times we check and re-check these directory
entries, in all cases. Thanks for the idea, Andreas).
Next we had a root directory inode which had a corrupted size, claimed to
be > 200M on a 4M filesystem. There was only really 1 block in the
directory, but because the size was so large, readdir kept coming back for
more, spewing thousands of printk's along the way.
Per Andreas' suggestion, if we're in this read error condition and we're
trying to read an offset which is greater than i_blocks worth of bytes,
stop trying, and break out of the loop.
With these two changes fsfuzz test survives quite well on ext3.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Andrew Morton
Mingming Cao
Aneesh Kumar K.V
Tim Schmielau
Josef 'Jeff' Sipek
Arjan van de Ven
Dmitriy Monakhov
Eric Sandeen
Hugh Dickins
David Howells
Andrey Savochkin
Andrew Morton