linux-toradex.git/fs, branch v3.14.3

ext4: use i_size_read in ext4_unaligned_aio()

2014-05-06T14:59:37+00:00

commit 6e6358fc3c3c862bfe9a5bc029d3f8ce43dc9765 upstream.

We haven't taken i_mutex yet, so we need to use i_size_read().

Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: move ext4_update_i_disksize() into mpage_map_and_submit_extent()

2014-05-06T14:59:37+00:00

commit 622cad1325e404598fe3b148c3fa640dbaabc235 upstream.

The function ext4_update_i_disksize() is used in only one place, in
the function mpage_map_and_submit_extent().  Move its code to simplify
the code paths, and also move the call to ext4_mark_inode_dirty() into
the i_data_sem's critical region, to be consistent with all of the
other places where we update i_disksize.  That way, we also keep the
raw_inode's i_disksize protected, to avoid the following race:

      CPU #1                                 CPU #2

   down_write(&i_data_sem)
   Modify i_disk_size
   up_write(&i_data_sem)
                                        down_write(&i_data_sem)
                                        Modify i_disk_size
                                        Copy i_disk_size to on-disk inode
                                        up_write(&i_data_sem)
   Copy i_disk_size to on-disk inode

Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ext4: fix jbd2 warning under heavy xattr load

2014-05-06T14:59:37+00:00

commit ec4cb1aa2b7bae18dd8164f2e9c7c51abcf61280 upstream.

When heavily exercising xattr code the assertion that
jbd2_journal_dirty_metadata() shouldn't return error was triggered:

WARNING: at /srv/autobuild-ceph/gitbuilder.git/build/fs/jbd2/transaction.c:1237
jbd2_journal_dirty_metadata+0x1ba/0x260()

CPU: 0 PID: 8877 Comm: ceph-osd Tainted: G    W 3.10.0-ceph-00049-g68d04c9 #1
Hardware name: Dell Inc. PowerEdge R410/01V648, BIOS 1.6.3 02/07/2011
 ffffffff81a1d3c8 ffff880214469928 ffffffff816311b0 ffff880214469968
 ffffffff8103fae0 ffff880214469958 ffff880170a9dc30 ffff8802240fbe80
 0000000000000000 ffff88020b366000 ffff8802256e7510 ffff880214469978
Call Trace:
 [] dump_stack+0x19/0x1b
 [] warn_slowpath_common+0x70/0xa0
 [] warn_slowpath_null+0x1a/0x20
 [] jbd2_journal_dirty_metadata+0x1ba/0x260
 [] __ext4_handle_dirty_metadata+0xa3/0x140
 [] ext4_xattr_release_block+0x103/0x1f0
 [] ext4_xattr_block_set+0x1e0/0x910
 [] ext4_xattr_set_handle+0x38b/0x4a0
 [] ? trace_hardirqs_on+0xd/0x10
 [] ext4_xattr_set+0xc2/0x140
 [] ext4_xattr_user_set+0x47/0x50
 [] generic_setxattr+0x6e/0x90
 [] __vfs_setxattr_noperm+0x7b/0x1c0
 [] vfs_setxattr+0xc4/0xd0
 [] setxattr+0x13e/0x1e0
 [] ? __sb_start_write+0xe7/0x1b0
 [] ? mnt_want_write_file+0x28/0x60
 [] ? fget_light+0x3c/0x130
 [] ? mnt_want_write_file+0x28/0x60
 [] ? __mnt_want_write+0x58/0x70
 [] SyS_fsetxattr+0xbe/0x100
 [] system_call_fastpath+0x16/0x1b

The reason for the warning is that buffer_head passed into
jbd2_journal_dirty_metadata() didn't have journal_head attached. This is
caused by the following race of two ext4_xattr_release_block() calls:

CPU1                                CPU2
ext4_xattr_release_block()          ext4_xattr_release_block()
lock_buffer(bh);
/* False */
if (BHDR(bh)->h_refcount == cpu_to_le32(1))
} else {
  le32_add_cpu(&BHDR(bh)->h_refcount, -1);
  unlock_buffer(bh);
                                    lock_buffer(bh);
                                    /* True */
                                    if (BHDR(bh)->h_refcount == cpu_to_le32(1))
                                      get_bh(bh);
                                      ext4_free_blocks()
                                        ...
                                        jbd2_journal_forget()
                                          jbd2_journal_unfile_buffer()
                                          -> JH is gone
  error = ext4_handle_dirty_xattr_block(handle, inode, bh);
  -> triggers the warning

We fix the problem by moving ext4_handle_dirty_xattr_block() under the
buffer lock. Sadly this cannot be done in nojournal mode as that
function can call sync_dirty_buffer() which would deadlock. Luckily in
nojournal mode the race is harmless (we only dirty already freed buffer)
and thus for nojournal mode we leave the dirtying outside of the buffer
lock.

Reported-by: Sage Weil 
Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: note the error in ext4_end_bio()

2014-05-06T14:59:37+00:00

commit 9503c67c93ed0b95ba62d12d1fd09da6245dbdd6 upstream.

ext4_end_bio() currently throws away the error that it receives.  Chances
are this is part of a spate of errors, one of which will end up getting
the error returned to userspace somehow, but we shouldn't take that risk.
Also print out the errno to aid in debug.

Signed-off-by: Matthew Wilcox 
Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ext4: FIBMAP ioctl causes BUG_ON due to handle EXT_MAX_BLOCKS

2014-05-06T14:59:36+00:00

commit 4adb6ab3e0fa71363a5ef229544b2d17de6600d7 upstream.

When we try to get 2^32-1 block of the file which has the extent
(ee_block=2^32-2, ee_len=1) with FIBMAP ioctl, it causes BUG_ON
in ext4_ext_put_gap_in_cache().

To avoid the problem, ext4_map_blocks() needs to check the file logical block
number. ext4_ext_put_gap_in_cache() called via ext4_map_blocks() cannot
handle 2^32-1 because the maximum file logical block number is 2^32-2.

Note that ext4_ind_map_blocks() returns -EIO when the block number is invalid.
So ext4_map_blocks() should also return the same errno.

Signed-off-by: Kazuya Mio 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

smarter propagate_mnt()

2014-05-06T14:59:36+00:00

commit f2ebb3a921c1ca1e2ddd9242e95a1989a50c4c68 upstream.

The current mainline has copies propagated to *all* nodes, then
tears down the copies we made for nodes that do not contain
counterparts of the desired mountpoint.  That sets the right
propagation graph for the copies (at teardown time we move
the slaves of removed node to a surviving peer or directly
to master), but we end up paying a fairly steep price in
useless allocations.  It's fairly easy to create a situation
where N calls of mount(2) create exactly N bindings, with
O(N^2) vfsmounts allocated and freed in process.

Fortunately, it is possible to avoid those allocations/freeings.
The trick is to create copies in the right order and find which
one would've eventually become a master with the current algorithm.
It turns out to be possible in O(nodes getting propagation) time
and with no extra allocations at all.

One part is that we need to make sure that eventual master will be
created before its slaves, so we need to walk the propagation
tree in a different order - by peer groups.  And iterate through
the peers before dealing with the next group.

Another thing is finding the (earlier) copy that will be a master
of one we are about to create; to do that we are (temporary) marking
the masters of mountpoints we are attaching the copies to.

Either we are in a peer of the last mountpoint we'd dealt with,
or we have the following situation: we are attaching to mountpoint M,
the last copy S_0 had been attached to M_0 and there are sequences
S_0...S_n, M_0...M_n such that S_{i+1} is a master of S_{i},
S_{i} mounted on M{i} and we need to create a slave of the first S_{k}
such that M is getting propagation from M_{k}.  It means that the master
of M_{k} will be among the sequence of masters of M.  On the
other hand, the nearest marked node in that sequence will either
be the master of M_{k} or the master of M_{k-1} (the latter -
in the case if M_{k-1} is a slave of something M gets propagation
from, but in a wrong peer group).

So we go through the sequence of masters of M until we find
a marked one (P).  Let N be the one before it.  Then we go through
the sequence of masters of S_0 until we find one (say, S) mounted
on a node D that has P as master and check if D is a peer of N.
If it is, S will be the master of new copy, if not - the master of S
will be.

That's it for the hard part; the rest is fairly simple.  Iterator
is in next_group(), handling of one prospective mountpoint is
propagate_one().

It seems to survive all tests and gives a noticably better performance
than the current mainline for setups that are seriously using shared
subtrees.

Signed-off-by: Al Viro 
Signed-off-by: Greg Kroah-Hartman

ocfs2: fix panic on kfree(xattr->name)

2014-05-06T14:59:36+00:00

commit f81c20158f8d5f7938d5eb86ecc42ecc09273ce6 upstream.

Commit 9548906b2bb7 ('xattr: Constify ->name member of "struct xattr"')
missed that ocfs2 is calling kfree(xattr->name).  As a result, kernel
panic occurs upon calling kfree(xattr->name) because xattr->name refers
static constant names.  This patch removes kfree(xattr->name) from
ocfs2_mknod() and ocfs2_symlink().

Signed-off-by: Tetsuo Handa 
Reported-by: Tariq Saeed 
Tested-by: Tariq Saeed 
Reviewed-by: Srinivas Eeda 
Cc: Joel Becker 
Cc: Mark Fasheh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2: do not put bh when buffer_uptodate failed

2014-05-06T14:59:36+00:00

commit f7cf4f5bfe073ad792ab49c04f247626b3e38db6 upstream.

Do not put bh when buffer_uptodate failed in ocfs2_write_block and
ocfs2_write_super_or_backup, because it will put bh in b_end_io.
Otherwise it will hit a warning "VFS: brelse: Trying to free free
buffer".

Signed-off-by: Alex Chen 
Reviewed-by: Joseph Qi 
Reviewed-by: Srinivas Eeda 
Cc: Mark Fasheh 
Acked-by: Joel Becker 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2: dlm: fix recovery hung

2014-05-06T14:59:36+00:00

commit ded2cf71419b9353060e633b59e446c42a6a2a09 upstream.

There is a race window in dlm_do_recovery() between dlm_remaster_locks()
and dlm_reset_recovery() when the recovery master nearly finish the
recovery process for a dead node.  After the master sends FINALIZE_RECO
message in dlm_remaster_locks(), another node may become the recovery
master for another dead node, and then send the BEGIN_RECO message to
all the nodes included the old master, in the handler of this message
dlm_begin_reco_handler() of old master, dlm->reco.dead_node and
dlm->reco.new_master will be set to the second dead node and the new
master, then in dlm_reset_recovery(), these two variables will be reset
to default value.  This will cause new recovery master can not finish
the recovery process and hung, at last the whole cluster will hung for
recovery.

old recovery master:                                 new recovery master:
dlm_remaster_locks()
                                                  become recovery master for
                                                  another dead node.
                                                  dlm_send_begin_reco_message()
dlm_begin_reco_handler()
{
 if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
  return -EAGAIN;
 }
 dlm_set_reco_master(dlm, br->node_idx);
 dlm_set_reco_dead_node(dlm, br->dead_node);
}
dlm_reset_recovery()
{
 dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
}
                                                  will hang in dlm_remaster_locks() for
                                                  request dlm locks info

Before send FINALIZE_RECO message, recovery master should set
DLM_RECO_STATE_FINALIZE for itself and clear it after the recovery done,
this can break the race windows as the BEGIN_RECO messages will not be
handled before DLM_RECO_STATE_FINALIZE flag is cleared.

A similar race may happen between new recovery master and normal node
which is in dlm_finalize_reco_handler(), also fix it.

Signed-off-by: Junxiao Bi 
Reviewed-by: Srinivas Eeda 
Reviewed-by: Wengang Wang 
Cc: Joel Becker 
Cc: Mark Fasheh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2: dlm: fix lock migration crash

2014-05-06T14:59:35+00:00

commit 34aa8dac482f1358d59110d5e3a12f4351f6acaa upstream.

This issue was introduced by commit 800deef3f6f8 ("ocfs2: use
list_for_each_entry where benefical") in 2007 where it replaced
list_for_each with list_for_each_entry.  The variable "lock" will point
to invalid data if "tmpq" list is empty and a panic will be triggered
due to this.  Sunil advised reverting it back, but the old version was
also not right.  At the end of the outer for loop, that
list_for_each_entry will also set "lock" to an invalid data, then in the
next loop, if the "tmpq" list is empty, "lock" will be an stale invalid
data and cause the panic.  So reverting the list_for_each back and reset
"lock" to NULL to fix this issue.

Another concern is that this seemes can not happen because the "tmpq"
list should not be empty.  Let me describe how.

old lock resource owner(node 1):                                  migratation target(node 2):
image there's lockres with a EX lock from node 2 in
granted list, a NR lock from node x with convert_type
EX in converting list.
dlm_empty_lockres() {
 dlm_pick_migration_target() {
   pick node 2 as target as its lock is the first one
   in granted list.
 }
 dlm_migrate_lockres() {
   dlm_mark_lockres_migrating() {
     res->state |= DLM_LOCK_RES_BLOCK_DIRTY;
     wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res));
	 //after the above code, we can not dirty lockres any more,
     // so dlm_thread shuffle list will not run
                                                                   downconvert lock from EX to NR
                                                                   upconvert lock from NR to EX
<<< migration may schedule out here, then
<<< node 2 send down convert request to convert type from EX to
<<< NR, then send up convert request to convert type from NR to
<<< EX, at this time, lockres granted list is empty, and two locks
<<< in the converting list, node x up convert lock followed by
<<< node 2 up convert lock.

	 // will set lockres RES_MIGRATING flag, the following
	 // lock/unlock can not run
     dlm_lockres_release_ast(dlm, res);
   }

   dlm_send_one_lockres()
                                                                 dlm_process_recovery_data()
                                                                   for (i=0; inum_locks; i++)
                                                                     if (ml->node == dlm->node_num)
                                                                       for (j = DLM_GRANTED_LIST; j <= DLM_BLOCKED_LIST; j++) {
                                                                        list_for_each_entry(lock, tmpq, list)
                                                                        if (lock) break; <<< lock is invalid as grant list is empty.
                                                                       }
                                                                       if (lock->ml.node != ml->node)
                                                                         BUG() >>> crash here
 }

I see the above locks status from a vmcore of our internal bug.

Signed-off-by: Junxiao Bi 
Reviewed-by: Wengang Wang 
Cc: Sunil Mushran 
Reviewed-by: Srinivas Eeda 
Cc: Joel Becker 
Cc: Mark Fasheh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman