x86, vdso: Make the vdso linker script compatible with Gold

Gold can't parse the script due to:
https://sourceware.org/bugzilla/show_bug.cgi?id=16804

With a workaround in place for that issue, Gold 2.23 crashes due to:
https://sourceware.org/bugzilla/show_bug.cgi?id=15355

This works around the former bug and avoids the second by removing
the unnecessary vvar and hpet sections and segments.  The vdso and
hpet symbols are still there, and nothing needed the sections or
segments.

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/243fa205098d112ec759c9b1b26785c09f399833.1396547532.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
ext4: fix 64-bit number truncation warning

'0x7FDEADBEEF' will be truncated to 32-bit number under unicore32. Need
append 'ULL' for it.

The related warning (with allmodconfig under unicore32):

    CC [M]  fs/ext4/extents_status.o
  fs/ext4/extents_status.c: In function "__es_remove_extent":
  fs/ext4/extents_status.c:813: warning: integer constant is too large for "long" type

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: FIBMAP ioctl causes BUG_ON due to handle EXT_MAX_BLOCKS

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 <k-mio@sx.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
ext4: initialize multi-block allocator before checking block descriptors

With EXT4FS_DEBUG ext4_count_free_clusters() will call
ext4_read_block_bitmap() without s_group_info initialized, so we need to
initialize multi-block allocator before.

And dependencies that must be solved, to allow this:
- multi-block allocator needs in group descriptors
- need to install s_op before initializing multi-block allocator,
  because in ext4_mb_init_backend() new inode is created.
- initialize number of group desc blocks (s_gdb_count) otherwise
  number of clusters returned by ext4_free_clusters_after_init() is not correct.
  (see ext4_bg_num_gdb_nometa())

Here is the stack backtrace:

(gdb) bt
 #0  ext4_get_group_info (group=0, sb=0xffff880079a10000) at ext4.h:2430
 #1  ext4_validate_block_bitmap (sb=sb@entry=0xffff880079a10000,
     desc=desc@entry=0xffff880056510000, block_group=block_group@entry=0,
     bh=bh@entry=0xffff88007bf2b2d8) at balloc.c:358
 #2  0xffffffff81232202 in ext4_wait_block_bitmap (sb=sb@entry=0xffff880079a10000,
     block_group=block_group@entry=0,
     bh=bh@entry=0xffff88007bf2b2d8) at balloc.c:476
 #3  0xffffffff81232eaf in ext4_read_block_bitmap (sb=sb@entry=0xffff880079a10000,
     block_group=block_group@entry=0) at balloc.c:489
 #4  0xffffffff81232fc0 in ext4_count_free_clusters (sb=sb@entry=0xffff880079a10000) at balloc.c:665
 #5  0xffffffff81259ffa in ext4_check_descriptors (first_not_zeroed=<synthetic pointer>,
     sb=0xffff880079a10000) at super.c:2143
 #6  ext4_fill_super (sb=sb@entry=0xffff880079a10000, data=<optimized out>,
     data@entry=0x0 <irq_stack_union>, silent=silent@entry=0) at super.c:3851
     ...

Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: note the error in ext4_end_bio()

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 <matthew.r.wilcox@intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
ext4: fix jbd2 warning under heavy xattr load

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:
 [<ffffffff816311b0>] dump_stack+0x19/0x1b
 [<ffffffff8103fae0>] warn_slowpath_common+0x70/0xa0
 [<ffffffff8103fb2a>] warn_slowpath_null+0x1a/0x20
 [<ffffffff81267c2a>] jbd2_journal_dirty_metadata+0x1ba/0x260
 [<ffffffff81245093>] __ext4_handle_dirty_metadata+0xa3/0x140
 [<ffffffff812561f3>] ext4_xattr_release_block+0x103/0x1f0
 [<ffffffff81256680>] ext4_xattr_block_set+0x1e0/0x910
 [<ffffffff8125795b>] ext4_xattr_set_handle+0x38b/0x4a0
 [<ffffffff810a319d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff81257b32>] ext4_xattr_set+0xc2/0x140
 [<ffffffff81258547>] ext4_xattr_user_set+0x47/0x50
 [<ffffffff811935ce>] generic_setxattr+0x6e/0x90
 [<ffffffff81193ecb>] __vfs_setxattr_noperm+0x7b/0x1c0
 [<ffffffff811940d4>] vfs_setxattr+0xc4/0xd0
 [<ffffffff8119421e>] setxattr+0x13e/0x1e0
 [<ffffffff811719c7>] ? __sb_start_write+0xe7/0x1b0
 [<ffffffff8118f2e8>] ? mnt_want_write_file+0x28/0x60
 [<ffffffff8118c65c>] ? fget_light+0x3c/0x130
 [<ffffffff8118f2e8>] ? mnt_want_write_file+0x28/0x60
 [<ffffffff8118f1f8>] ? __mnt_want_write+0x58/0x70
 [<ffffffff811946be>] SyS_fsetxattr+0xbe/0x100
 [<ffffffff816407c2>] 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 <sage@inktank.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
ext4: update PF_MEMALLOC handling in ext4_write_inode()

The special handling of PF_MEMALLOC callers in ext4_write_inode()
shouldn't be necessary as there shouldn't be any. Warn about it. Also
update comment before the function as it seems somewhat outdated.

(Changes modeled on an ext3 patch posted by Jan Kara to the linux-ext4
mailing list on Februaryt 28, 2014, which apparently never went into
the ext3 tree.)

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
ext4: fix COLLAPSE_RANGE test failure in data journalling mode

When mounting ext4 with data=journal option, xfstest shared/002 and
shared/004 are currently failing as checksum computed for testfile
does not match with the checksum computed in other journal modes.
In case of data=journal mode, a call to filemap_write_and_wait_range
will not flush anything to disk as buffers are not marked dirty in
write_end. In collapse range this call is followed by a call to
truncate_pagecache_range. Due to this, when checksum is computed,
a portion of file is re-read from disk which replace valid data with
NULL bytes and hence the reason for the difference in checksum.

Calling ext4_force_commit before filemap_write_and_wait_range solves
the issue as it will mark the buffers dirty during commit transaction
which can be later synced by a call to filemap_write_and_wait_range.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: return ENOMEM rather than EIO when find_###_page() fails

Return ENOMEM rather than EIO when find_get_page() fails in
ext4_mb_get_buddy_page_lock() and find_or_create_page() fails in
ext4_mb_load_buddy().

Signed-off-by: Younger Liu <younger.liucn@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: move ext4_update_i_disksize() into mpage_map_and_submit_extent()

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" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
ext4: remove unnecessary check for APPEND and IMMUTABLE

All the checks IS_APPEND and IS_IMMUTABLE for the fallocate operation on
the inode are done in vfs. No need to do this again in ext4. Remove it.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
fs: prevent doing FALLOC_FL_ZERO_RANGE on append only file

Currently punch hole and collapse range fallocate operation are not
allowed on append only file. This should be case for zero range as well.
Fix it by allowing only pure fallocate (possibly with keep size set).

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
fs: move falloc collapse range check into the filesystem methods

Currently in do_fallocate in collapse range case we're checking
whether offset + len is not bigger than i_size.  However there is
nothing which would prevent i_size from changing so the check is
pointless.  It should be done in the file system itself and the file
system needs to make sure that i_size is not going to change.  The
i_size check for the other fallocate modes are also done in the
filesystems.

As it is now we can easily crash the kernel by having two processes
doing truncate and fallocate collapse range at the same time.  This
can be reproduced on ext4 and it is theoretically possible on xfs even
though I was not able to trigger it with this simple test.

This commit removes the check from do_fallocate and adds it to the
file system.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
fs: disallow all fallocate operation on active swapfile

Currently some file system have IS_SWAPFILE check in their fallocate
implementations and some do not. However we should really prevent any
fallocate operation on swapfile so move the check to vfs and remove the
redundant checks from the file systems fallocate implementations.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: use i_size_read in ext4_unaligned_aio()

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

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
ext4: fix byte order problems introduced by the COLLAPSE_RANGE patches

This commit tries to fix some byte order issues that is found by sparse
check.

$ make M=fs/ext4 C=2 CF=-D__CHECK_ENDIAN__
...
  CHECK   fs/ext4/extents.c
fs/ext4/extents.c:5232:41: warning: restricted __le32 degrades to integer
fs/ext4/extents.c:5236:52: warning: bad assignment (-=) to restricted __le32
fs/ext4/extents.c:5258:45: warning: bad assignment (-=) to restricted __le32
fs/ext4/extents.c:5303:28: warning: restricted __le32 degrades to integer
fs/ext4/extents.c:5318:18: warning: incorrect type in assignment (different base types)
fs/ext4/extents.c:5318:18:    expected unsigned int [unsigned] [usertype] ex_start
fs/ext4/extents.c:5318:18:    got restricted __le32 [usertype] ee_block
fs/ext4/extents.c:5319:24: warning: restricted __le32 degrades to integer
fs/ext4/extents.c:5334:31: warning: incorrect type in assignment (different base types)
...

Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: COLLAPSE_RANGE only works on extent-based files

Unfortunately, we weren't checking to make sure of this the inode was
extent-based before attempt operate on it.  Hilarity ensues.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
ext4: silence sparse check warning for function ext4_trim_extent

This fixes the following sparse warning:

     CHECK   fs/ext4/mballoc.c
   fs/ext4/mballoc.c:5019:9: warning: context imbalance in
   'ext4_trim_extent' - unexpected unlock

Signed-off-by: "Jon Ernst" <jonernst07@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: fix error handling in ext4_ext_shift_extents

Fix error handling by adding some.  :-)

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: always check ext4_ext_find_extent result

Where are some places where logic guaranties us that extent we are
searching exits, but this may not be true due to on-disk data
corruption. If such corruption happens we must prevent possible
null pointer dereferences.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>