Last kernel has already support new syscall statx() in commit a528d35e
("statx: Add a system call to make enhanced file info available"), with
this interface we can show more file info including file creation and some
attribute flags to user.

This patch tries to support this functionality.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fixes missing inode flag loaded from disk, reported by Tom.

[tom@localhost ~]$ sudo mount /dev/loop0 /mnt/
[tom@localhost ~]$ sudo chown tom:tom /mnt/
[tom@localhost ~]$ touch /mnt/testfile
[tom@localhost ~]$ sudo chattr +i /mnt/testfile
[tom@localhost ~]$ echo test > /mnt/testfile
bash: /mnt/testfile: Operation not permitted
[tom@localhost ~]$ rm /mnt/testfile
rm: cannot remove '/mnt/testfile': Operation not permitted
[tom@localhost ~]$ sudo umount /mnt/
[tom@localhost ~]$ sudo mount /dev/loop0 /mnt/
[tom@localhost ~]$ lsattr /mnt/testfile
----i-------------- /mnt/testfile
[tom@localhost ~]$ echo test > /mnt/testfile
[tom@localhost ~]$ rm /mnt/testfile
[tom@localhost ~]$ sudo umount /mnt/

Cc: stable@vger.kernel.org
Reported-by: NTom Yan <tom.ty89@outlook.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Make sure segno and blkoff read from raw image are valid.

Cc: stable@vger.kernel.org
Signed-off-by: NJin Qian <jinqian@google.com>
[Jaegeuk Kim: adjust minor coding style]
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This bug fixes a regression introduced by patch 0d1c7ae9.

The intent of the patch was to stop promoting glocks after a
file system is withdrawn due to a variety of errors, because doing
so results in a BUG(). (You should be able to unmount after a
withdraw rather than having the kernel panic.)

Unfortunately, it also stopped demotions, so glocks could not be
unlocked after withdraw, which means the unmount would hang.

This patch allows function do_xmote to demote locks to an
unlocked state after a withdraw, but not promote them.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>

Commit 28b783e4 ("xfs: bufferhead chains are invalid after
end_page_writeback") fixed one use-after-free issue by
pre-calculating the loop conditionals before calling bh->b_end_io()
in the end_io processing loop, but it assigned 'next' pointer before
checking end offset boundary & breaking the loop, at which point the
bh might be freed already, and caused use-after-free.

This is caught by KASAN when running fstests generic/127 on sub-page
block size XFS.

[ 2517.244502] run fstests generic/127 at 2017-04-27 07:30:50
[ 2747.868840] ==================================================================
[ 2747.876949] BUG: KASAN: use-after-free in xfs_destroy_ioend+0x3d3/0x4e0 [xfs] at addr ffff8801395ae698
...
[ 2747.918245] Call Trace:
[ 2747.920975]  dump_stack+0x63/0x84
[ 2747.924673]  kasan_object_err+0x21/0x70
[ 2747.928950]  kasan_report+0x271/0x530
[ 2747.933064]  ? xfs_destroy_ioend+0x3d3/0x4e0 [xfs]
[ 2747.938409]  ? end_page_writeback+0xce/0x110
[ 2747.943171]  __asan_report_load8_noabort+0x19/0x20
[ 2747.948545]  xfs_destroy_ioend+0x3d3/0x4e0 [xfs]
[ 2747.953724]  xfs_end_io+0x1af/0x2b0 [xfs]
[ 2747.958197]  process_one_work+0x5ff/0x1000
[ 2747.962766]  worker_thread+0xe4/0x10e0
[ 2747.966946]  kthread+0x2d3/0x3d0
[ 2747.970546]  ? process_one_work+0x1000/0x1000
[ 2747.975405]  ? kthread_create_on_node+0xc0/0xc0
[ 2747.980457]  ? syscall_return_slowpath+0xe6/0x140
[ 2747.985706]  ? do_page_fault+0x30/0x80
[ 2747.989887]  ret_from_fork+0x2c/0x40
[ 2747.993874] Object at ffff8801395ae690, in cache buffer_head size: 104
[ 2748.001155] Allocated:
[ 2748.003782] PID = 8327
[ 2748.006411]  save_stack_trace+0x1b/0x20
[ 2748.010688]  save_stack+0x46/0xd0
[ 2748.014383]  kasan_kmalloc+0xad/0xe0
[ 2748.018370]  kasan_slab_alloc+0x12/0x20
[ 2748.022648]  kmem_cache_alloc+0xb8/0x1b0
[ 2748.027024]  alloc_buffer_head+0x22/0xc0
[ 2748.031399]  alloc_page_buffers+0xd1/0x250
[ 2748.035968]  create_empty_buffers+0x30/0x410
[ 2748.040730]  create_page_buffers+0x120/0x1b0
[ 2748.045493]  __block_write_begin_int+0x17a/0x1800
[ 2748.050740]  iomap_write_begin+0x100/0x2f0
[ 2748.055308]  iomap_zero_range_actor+0x253/0x5c0
[ 2748.060362]  iomap_apply+0x157/0x270
[ 2748.064347]  iomap_zero_range+0x5a/0x80
[ 2748.068624]  iomap_truncate_page+0x6b/0xa0
[ 2748.073227]  xfs_setattr_size+0x1f7/0xa10 [xfs]
[ 2748.078312]  xfs_vn_setattr_size+0x68/0x140 [xfs]
[ 2748.083589]  xfs_file_fallocate+0x4ac/0x820 [xfs]
[ 2748.088838]  vfs_fallocate+0x2cf/0x780
[ 2748.093021]  SyS_fallocate+0x48/0x80
[ 2748.097006]  do_syscall_64+0x18a/0x430
[ 2748.101186]  return_from_SYSCALL_64+0x0/0x6a
[ 2748.105948] Freed:
[ 2748.108189] PID = 8327
[ 2748.110816]  save_stack_trace+0x1b/0x20
[ 2748.115093]  save_stack+0x46/0xd0
[ 2748.118788]  kasan_slab_free+0x73/0xc0
[ 2748.122969]  kmem_cache_free+0x7a/0x200
[ 2748.127247]  free_buffer_head+0x41/0x80
[ 2748.131524]  try_to_free_buffers+0x178/0x250
[ 2748.136316]  xfs_vm_releasepage+0x2e9/0x3d0 [xfs]
[ 2748.141563]  try_to_release_page+0x100/0x180
[ 2748.146325]  invalidate_inode_pages2_range+0x7da/0xcf0
[ 2748.152087]  xfs_shift_file_space+0x37d/0x6e0 [xfs]
[ 2748.157557]  xfs_collapse_file_space+0x49/0x120 [xfs]
[ 2748.163223]  xfs_file_fallocate+0x2a7/0x820 [xfs]
[ 2748.168462]  vfs_fallocate+0x2cf/0x780
[ 2748.172642]  SyS_fallocate+0x48/0x80
[ 2748.176629]  do_syscall_64+0x18a/0x430
[ 2748.180810]  return_from_SYSCALL_64+0x0/0x6a

Fixed it by checking on offset against end & breaking out first,
dereference bh only if there're still bufferheads to process.
Signed-off-by: NEryu Guan <eguan@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

SFM is mapping doublequote to 0xF020

Without this patch creating files with doublequote fails to Windows/Mac
Signed-off-by: NBjoern Jacke <bjacke@samba.org>
Signed-off-by: NSteve French <smfrench@gmail.com>
CC: stable <stable@vger.kernel.org>

based on commit b3b42c0d
("fs/affs: make export work with cold dcache")

This adds get_parent function so that nfs client can still work after
cache drop (Tested on NFS v4 with echo 3 > /proc/sys/vm/drop_caches)
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NLuis de Bethencourt <luisbg@osg.samsung.com>

A large directory full of differently sized file names triggered this.
Most directories, even very large directories with shorter names, would
be lucky enough to fit in one server response.
Signed-off-by: NMartin Brandenburg <martin@omnibond.com>
Signed-off-by: NMike Marshall <hubcap@omnibond.com>

If an application seeks to a position before the point which has been
read, it must want updates which have been made to the directory.  So
delete the copy stored in the kernel so it will be fetched again.
Signed-off-by: NMartin Brandenburg <martin@omnibond.com>
Signed-off-by: NMike Marshall <hubcap@omnibond.com>

If userspace seeks to a position in the stream which is not correct, it
would have returned EIO because the data in the buffer at that offset
would be incorrect.  This and the userspace daemon returning a corrupt
directory are indistinguishable.

Now if the data does not look right, skip forward to the next chunk and
try again.  The motivation is that if the directory changes, an
application may seek to a position that was valid and no longer is valid.

It is not yet possible for a directory to change.
Signed-off-by: NMartin Brandenburg <martin@omnibond.com>
Signed-off-by: NMike Marshall <hubcap@omnibond.com>

When ext4 encryption was originally merged, we were encrypting the
user-specified filename in ext4_match(), introducing a lot of additional
complexity into ext4_match() and its callers.  This has since been
changed to encrypt the filename earlier, so we can remove the gunk
that's no longer needed.  This more or less reverts ext4_search_dir()
and ext4_find_dest_de() to the way they were in the v4.0 kernel.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Switch f2fs directory searches to use the fscrypt_match_name() helper
function.  There should be no functional change.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Acked-by: NJaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Switch ext4 directory searches to use the fscrypt_match_name() helper
function.  There should be no functional change.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Introduce a helper function fscrypt_match_name() which tests whether a
fscrypt_name matches a directory entry.  Also clean up the magic numbers
and document things properly.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

When accessing an encrypted directory without the key, userspace must
operate on filenames derived from the ciphertext names, which contain
arbitrary bytes.  Since we must support filenames as long as NAME_MAX,
we can't always just base64-encode the ciphertext, since that may make
it too long.  Currently, this is solved by presenting long names in an
abbreviated form containing any needed filesystem-specific hashes (e.g.
to identify a directory block), then the last 16 bytes of ciphertext.
This needs to be sufficient to identify the actual name on lookup.

However, there is a bug.  It seems to have been assumed that due to the
use of a CBC (ciphertext block chaining)-based encryption mode, the last
16 bytes (i.e. the AES block size) of ciphertext would depend on the
full plaintext, preventing collisions.  However, we actually use CBC
with ciphertext stealing (CTS), which handles the last two blocks
specially, causing them to appear "flipped".  Thus, it's actually the
second-to-last block which depends on the full plaintext.

This caused long filenames that differ only near the end of their
plaintexts to, when observed without the key, point to the wrong inode
and be undeletable.  For example, with ext4:

    # echo pass | e4crypt add_key -p 16 edir/
    # seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
    # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
    100000
    # sync
    # echo 3 > /proc/sys/vm/drop_caches
    # keyctl new_session
    # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
    2004
    # rm -rf edir/
    rm: cannot remove 'edir/_A7nNFi3rhkEQlJ6P,hdzluhODKOeWx5V': Structure needs cleaning
    ...

To fix this, when presenting long encrypted filenames, encode the
second-to-last block of ciphertext rather than the last 16 bytes.

Although it would be nice to solve this without depending on a specific
encryption mode, that would mean doing a cryptographic hash like SHA-256
which would be much less efficient.  This way is sufficient for now, and
it's still compatible with encryption modes like HEH which are strong
pseudorandom permutations.  Also, changing the presented names is still
allowed at any time because they are only provided to allow applications
to do things like delete encrypted directories.  They're not designed to
be used to persistently identify files --- which would be hard to do
anyway, given that they're encrypted after all.

For ease of backports, this patch only makes the minimal fix to both
ext4 and f2fs.  It leaves ubifs as-is, since ubifs doesn't compare the
ciphertext block yet.  Follow-on patches will clean things up properly
and make the filesystems use a shared helper function.

Fixes: 5de0b4d0 ("ext4 crypto: simplify and speed up filename encryption")
Reported-by: NGwendal Grignou <gwendal@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

If user has no key under an encrypted dir, fscrypt gives digested dentries.
Previously, when looking up a dentry, f2fs only checks its hash value with
first 4 bytes of the digested dentry, which didn't handle hash collisions fully.
This patch enhances to check entire dentry bytes likewise ext4.

Eric reported how to reproduce this issue by:

 # seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
 # find edir -type f | xargs stat -c %i | sort | uniq | wc -l
100000
 # sync
 # echo 3 > /proc/sys/vm/drop_caches
 # keyctl new_session
 # find edir -type f | xargs stat -c %i | sort | uniq | wc -l
99999

Cc: <stable@vger.kernel.org>
Reported-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
(fixed f2fs_dentry_hash() to work even when the hash is 0)
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

As ext4 and f2fs do, ubifs should check for consistent encryption
contexts during ->lookup() in an encrypted directory.  This protects
certain users of filesystem encryption against certain types of offline
attacks.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

As for ext4, now that fscrypt_has_permitted_context() correctly handles
the case where we have the key for the parent directory but not the
child, f2fs_lookup() no longer has to work around it.  Also add the same
warning message that ext4 uses.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Now that fscrypt_has_permitted_context() correctly handles the case
where we have the key for the parent directory but not the child, we
don't need to try to work around this in ext4_lookup().
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

To mitigate some types of offline attacks, filesystem encryption is
designed to enforce that all files in an encrypted directory tree use
the same encryption policy (i.e. the same encryption context excluding
the nonce).  However, the fscrypt_has_permitted_context() function which
enforces this relies on comparing struct fscrypt_info's, which are only
available when we have the encryption keys.  This can cause two
incorrect behaviors:

1. If we have the parent directory's key but not the child's key, or
   vice versa, then fscrypt_has_permitted_context() returned false,
   causing applications to see EPERM or ENOKEY.  This is incorrect if
   the encryption contexts are in fact consistent.  Although we'd
   normally have either both keys or neither key in that case since the
   master_key_descriptors would be the same, this is not guaranteed
   because keys can be added or removed from keyrings at any time.

2. If we have neither the parent's key nor the child's key, then
   fscrypt_has_permitted_context() returned true, causing applications
   to see no error (or else an error for some other reason).  This is
   incorrect if the encryption contexts are in fact inconsistent, since
   in that case we should deny access.

To fix this, retrieve and compare the fscrypt_contexts if we are unable
to set up both fscrypt_infos.

While this slightly hurts performance when accessing an encrypted
directory tree without the key, this isn't a case we really need to be
optimizing for; access *with* the key is much more important.
Furthermore, the performance hit is barely noticeable given that we are
already retrieving the fscrypt_context and doing two keyring searches in
fscrypt_get_encryption_info().  If we ever actually wanted to optimize
this case we might start by caching the fscrypt_contexts.

Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Currently jbd2_write_superblock() silently adds REQ_SYNC to flags with
which journal superblock is written. Make this explicit by making flags
passed down to jbd2_write_superblock() contain REQ_SYNC.

CC: linux-ext4@vger.kernel.org
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Commit b685d3d6 "block: treat REQ_FUA and REQ_PREFLUSH as
synchronous" removed REQ_SYNC flag from WRITE_FUA implementation.
generic_make_request_checks() however strips REQ_FUA flag from a bio
when the storage doesn't report volatile write cache and thus write
effectively becomes asynchronous which can lead to performance
regressions. This affects superblock writes for ext4. Fix the problem
by marking superblock writes always as synchronous.

Fixes: b685d3d6
CC: linux-ext4@vger.kernel.org
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

In commit 0d3b12584972 "nfs: Convert to separately allocated bdi" I have
wrongly cloned bdi reference in nfs_clone_super(). Further inspection
has shown that originally the code was actually allocating a new bdi (in
->clone_server callback) which was later registered in
nfs_fs_mount_common() and used for sb->s_bdi in nfs_initialise_sb().
This could later result in bdi for the original superblock not getting
unregistered when that superblock got shutdown (as the cloned sb still
held bdi reference) and later when a new superblock was created under
the same anonymous device number, a clash in sysfs has happened on bdi
registration:

------------[ cut here ]------------
WARNING: CPU: 1 PID: 10284 at /linux-next/fs/sysfs/dir.c:31 sysfs_warn_dup+0x64/0x74
sysfs: cannot create duplicate filename '/devices/virtual/bdi/0:32'
Modules linked in: axp20x_usb_power gpio_axp209 nvmem_sunxi_sid sun4i_dma sun4i_ss virt_dma
CPU: 1 PID: 10284 Comm: mount.nfs Not tainted 4.11.0-rc4+ #14
Hardware name: Allwinner sun7i (A20) Family
[<c010f19c>] (unwind_backtrace) from [<c010bc74>] (show_stack+0x10/0x14)
[<c010bc74>] (show_stack) from [<c03c6e24>] (dump_stack+0x78/0x8c)
[<c03c6e24>] (dump_stack) from [<c0122200>] (__warn+0xe8/0x100)
[<c0122200>] (__warn) from [<c0122250>] (warn_slowpath_fmt+0x38/0x48)
[<c0122250>] (warn_slowpath_fmt) from [<c02ac178>] (sysfs_warn_dup+0x64/0x74)
[<c02ac178>] (sysfs_warn_dup) from [<c02ac254>] (sysfs_create_dir_ns+0x84/0x94)
[<c02ac254>] (sysfs_create_dir_ns) from [<c03c8b8c>] (kobject_add_internal+0x9c/0x2ec)
[<c03c8b8c>] (kobject_add_internal) from [<c03c8e24>] (kobject_add+0x48/0x98)
[<c03c8e24>] (kobject_add) from [<c048d75c>] (device_add+0xe4/0x5a0)
[<c048d75c>] (device_add) from [<c048ddb4>] (device_create_groups_vargs+0xac/0xbc)
[<c048ddb4>] (device_create_groups_vargs) from [<c048dde4>] (device_create_vargs+0x20/0x28)
[<c048dde4>] (device_create_vargs) from [<c02075c8>] (bdi_register_va+0x44/0xfc)
[<c02075c8>] (bdi_register_va) from [<c023d378>] (super_setup_bdi_name+0x48/0xa4)
[<c023d378>] (super_setup_bdi_name) from [<c0312ef4>] (nfs_fill_super+0x1a4/0x204)
[<c0312ef4>] (nfs_fill_super) from [<c03133f0>] (nfs_fs_mount_common+0x140/0x1e8)
[<c03133f0>] (nfs_fs_mount_common) from [<c03335cc>] (nfs4_remote_mount+0x50/0x58)
[<c03335cc>] (nfs4_remote_mount) from [<c023ef98>] (mount_fs+0x14/0xa4)
[<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128)
[<c025cba0>] (vfs_kern_mount) from [<c033352c>] (nfs_do_root_mount+0x80/0xa0)
[<c033352c>] (nfs_do_root_mount) from [<c0333818>] (nfs4_try_mount+0x28/0x3c)
[<c0333818>] (nfs4_try_mount) from [<c0313874>] (nfs_fs_mount+0x2cc/0x8c4)
[<c0313874>] (nfs_fs_mount) from [<c023ef98>] (mount_fs+0x14/0xa4)
[<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128)
[<c025cba0>] (vfs_kern_mount) from [<c02600f0>] (do_mount+0x158/0xc7c)
[<c02600f0>] (do_mount) from [<c0260f98>] (SyS_mount+0x8c/0xb4)
[<c0260f98>] (SyS_mount) from [<c0107840>] (ret_fast_syscall+0x0/0x3c)

Fix the problem by always creating new bdi for a superblock as we used
to do.
Reported-and-tested-by: NCorentin Labbe <clabbe.montjoie@gmail.com>
Fixes: 0d3b12584972ce5781179ad3f15cca3cdb5cae05
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@fb.com>

Macs send the maximum buffer size in response on ioctl to validate
negotiate security information, which causes us to fail the mount
as the response buffer is larger than the expected response.

Changed ioctl response processing to allow for padding of validate
negotiate ioctl response and limit the maximum response size to
maximum buffer size.
Signed-off-by: NSteve French <steve.french@primarydata.com>
CC: Stable <stable@vger.kernel.org>

-write_checkpoint
   -do_checkpoint
      -next_free_nid    <--- something wrong with next free nid

-f2fs_fill_super
   -build_node_manager
      -build_free_nids
          -get_current_nat_page
             -__get_meta_page   <--- attempt to access beyond end of device
Signed-off-by: NYunlei He <heyunlei@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

An open directory may have a NULL private_data pointer prior to readdir.

Fixes: 0de1f4c6 ("Add way to query server fs info for smb3")
Cc: stable@vger.kernel.org
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Signed-off-by: NSteve French <smfrench@gmail.com>

- trailing space maps to 0xF028
- trailing period maps to 0xF029

This fix corrects the mapping of file names which have a trailing character
that would otherwise be illegal (period or space) but is allowed by POSIX.
Signed-off-by: NBjoern Jacke <bjacke@samba.org>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <smfrench@gmail.com>

invalidate_bdev() calls cleancache_invalidate_inode() iff ->nrpages != 0
which doen't make any sense.

Make sure that invalidate_bdev() always calls cleancache_invalidate_inode()
regardless of mapping->nrpages value.

Fixes: c515e1fd ("mm/fs: add hooks to support cleancache")
Link: http://lkml.kernel.org/r/20170424164135.22350-3-aryabinin@virtuozzo.comSigned-off-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Alexey Kuznetsov <kuznet@virtuozzo.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "Properly invalidate data in the cleancache", v2.

We've noticed that after direct IO write, buffered read sometimes gets
stale data which is coming from the cleancache.  The reason for this is
that some direct write hooks call call invalidate_inode_pages2[_range]()
conditionally iff mapping->nrpages is not zero, so we may not invalidate
data in the cleancache.

Another odd thing is that we check only for ->nrpages and don't check
for ->nrexceptional, but invalidate_inode_pages2[_range] also
invalidates exceptional entries as well.  So we invalidate exceptional
entries only if ->nrpages != 0? This doesn't feel right.

 - Patch 1 fixes direct IO writes by removing ->nrpages check.
 - Patch 2 fixes similar case in invalidate_bdev().
     Note: I only fixed conditional cleancache_invalidate_inode() here.
       Do we also need to add ->nrexceptional check in into invalidate_bdev()?

 - Patches 3-4: some optimizations.

This patch (of 4):

Some direct IO write fs hooks call invalidate_inode_pages2[_range]()
conditionally iff mapping->nrpages is not zero.  This can't be right,
because invalidate_inode_pages2[_range]() also invalidate data in the
cleancache via cleancache_invalidate_inode() call.  So if page cache is
empty but there is some data in the cleancache, buffered read after
direct IO write would get stale data from the cleancache.

Also it doesn't feel right to check only for ->nrpages because
invalidate_inode_pages2[_range] invalidates exceptional entries as well.

Fix this by calling invalidate_inode_pages2[_range]() regardless of
nrpages state.

Note: nfs,cifs,9p doesn't need similar fix because the never call
cleancache_get_page() (nor directly, nor via mpage_readpage[s]()), so
they are not affected by this bug.

Fixes: c515e1fd ("mm/fs: add hooks to support cleancache")
Link: http://lkml.kernel.org/r/20170424164135.22350-2-aryabinin@virtuozzo.comSigned-off-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Alexey Kuznetsov <kuznet@virtuozzo.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kjournald2 is central to the transaction commit processing.  As such any
potential allocation from this kernel thread has to be GFP_NOFS.  Make
sure to mark the whole kernel thread GFP_NOFS by the memalloc_nofs_save.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20170306131408.9828-8-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Suggested-by: NJan Kara <jack@suse.cz>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

now that we have memalloc_nofs_{save,restore} api we can mark the whole
transaction context as implicitly GFP_NOFS.  All allocations will
automatically inherit GFP_NOFS this way.  This means that we do not have
to mark any of those requests with GFP_NOFS and moreover all the
ext4_kv[mz]alloc(GFP_NOFS) are also safe now because even the hardcoded
GFP_KERNEL allocations deep inside the vmalloc will be NOFS now.

[akpm@linux-foundation.org: tweak comments]
Link: http://lkml.kernel.org/r/20170306131408.9828-7-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kmem_zalloc_large and _xfs_buf_map_pages use memalloc_noio_{save,restore}
API to prevent from reclaim recursion into the fs because vmalloc can
invoke unconditional GFP_KERNEL allocations and these functions might be
called from the NOFS contexts.  The memalloc_noio_save will enforce
GFP_NOIO context which is even weaker than GFP_NOFS and that seems to be
unnecessary.  Let's use memalloc_nofs_{save,restore} instead as it
should provide exactly what we need here - implicit GFP_NOFS context.

Link: http://lkml.kernel.org/r/20170306131408.9828-6-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

GFP_NOFS context is used for the following 5 reasons currently:

 - to prevent from deadlocks when the lock held by the allocation
   context would be needed during the memory reclaim

 - to prevent from stack overflows during the reclaim because the
   allocation is performed from a deep context already

 - to prevent lockups when the allocation context depends on other
   reclaimers to make a forward progress indirectly

 - just in case because this would be safe from the fs POV

 - silence lockdep false positives

Unfortunately overuse of this allocation context brings some problems to
the MM.  Memory reclaim is much weaker (especially during heavy FS
metadata workloads), OOM killer cannot be invoked because the MM layer
doesn't have enough information about how much memory is freeable by the
FS layer.

In many cases it is far from clear why the weaker context is even used
and so it might be used unnecessarily.  We would like to get rid of
those as much as possible.  One way to do that is to use the flag in
scopes rather than isolated cases.  Such a scope is declared when really
necessary, tracked per task and all the allocation requests from within
the context will simply inherit the GFP_NOFS semantic.

Not only this is easier to understand and maintain because there are
much less problematic contexts than specific allocation requests, this
also helps code paths where FS layer interacts with other layers (e.g.
crypto, security modules, MM etc...) and there is no easy way to convey
the allocation context between the layers.

Introduce memalloc_nofs_{save,restore} API to control the scope of
GFP_NOFS allocation context.  This is basically copying
memalloc_noio_{save,restore} API we have for other restricted allocation
context GFP_NOIO.  The PF_MEMALLOC_NOFS flag already exists and it is
just an alias for PF_FSTRANS which has been xfs specific until recently.
There are no more PF_FSTRANS users anymore so let's just drop it.

PF_MEMALLOC_NOFS is now checked in the MM layer and drops __GFP_FS
implicitly same as PF_MEMALLOC_NOIO drops __GFP_IO.  memalloc_noio_flags
is renamed to current_gfp_context because it now cares about both
PF_MEMALLOC_NOFS and PF_MEMALLOC_NOIO contexts.  Xfs code paths preserve
their semantic.  kmem_flags_convert() doesn't need to evaluate the flag
anymore.

This patch shouldn't introduce any functional changes.

Let's hope that filesystems will drop direct GFP_NOFS (resp.  ~__GFP_FS)
usage as much as possible and only use a properly documented
memalloc_nofs_{save,restore} checkpoints where they are appropriate.

[akpm@linux-foundation.org: fix comment typo, reflow comment]
Link: http://lkml.kernel.org/r/20170306131408.9828-5-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

xfs has defined PF_FSTRANS to declare a scope GFP_NOFS semantic quite
some time ago.  We would like to make this concept more generic and use
it for other filesystems as well.  Let's start by giving the flag a more
generic name PF_MEMALLOC_NOFS which is in line with an exiting
PF_MEMALLOC_NOIO already used for the same purpose for GFP_NOIO
contexts.  Replace all PF_FSTRANS usage from the xfs code in the first
step before we introduce a full API for it as xfs uses the flag directly
anyway.

This patch doesn't introduce any functional change.

Link: http://lkml.kernel.org/r/20170306131408.9828-4-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Show MADV_FREE pages info of each vma in smaps.  The interface is for
diganose or monitoring purpose, userspace could use it to understand
what happens in the application.  Since userspace could dirty MADV_FREE
pages without notice from kernel, this interface is the only place we
can get accurate accounting info about MADV_FREE pages.

[mhocko@kernel.org: update Documentation/filesystems/proc.txt]
Link: http://lkml.kernel.org/r/89efde633559de1ec07444f2ef0f4963a97a2ce8.1487965799.git.shli@fb.comSigned-off-by: NShaohua Li <shli@fb.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NMinchan Kim <minchan@kernel.org>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NHillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use offset_in_page() macro instead of open-coding.

Link: http://lkml.kernel.org/r/4dbc77ccaaed98b183cf4dba58a4fa325fd65048.1492758503.git.geliangtang@gmail.comSigned-off-by: NGeliang Tang <geliangtang@gmail.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Configfs is the interface for ocfs2-tools to set configure to kernel and
$configfs_dir/cluster/$clustername/heartbeat/dead_threshold is the one
used to configure heartbeat dead threshold.  Kernel has a default value
of it but user can set O2CB_HEARTBEAT_THRESHOLD in /etc/sysconfig/o2cb
to override it.

Commit 45b99773 ("ocfs2/cluster: use per-attribute show and store
methods") changed heartbeat dead threshold name while ocfs2-tools did
not, so ocfs2-tools won't set this configurable and the default value is
always used.  So revert it.

Fixes: 45b99773 ("ocfs2/cluster: use per-attribute show and store methods")
Link: http://lkml.kernel.org/r/1490665245-15374-1-git-send-email-junxiao.bi@oracle.comSigned-off-by: NJunxiao Bi <junxiao.bi@oracle.com>
Acked-by: NJoseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use setup_timer() instead of init_timer() to simplify the code.

Link: http://lkml.kernel.org/r/5e75bf07beb91e092d5aa36c36769949a480456a.1489060564.git.geliangtang@gmail.comSigned-off-by: NGeliang Tang <geliangtang@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch expands cover region of inode->i_rwsem to keep setting flag
atomically.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Commit b685d3d6 "block: treat REQ_FUA and REQ_PREFLUSH as
synchronous" removed REQ_SYNC flag from WRITE_{FUA|PREFLUSH|...}
definitions.  generic_make_request_checks() however strips REQ_FUA and
REQ_PREFLUSH flags from a bio when the storage doesn't report volatile
write cache and thus write effectively becomes asynchronous which can
lead to performance regressions.

Fix the problem by making sure all bios which are synchronous are
properly marked with REQ_SYNC.

Fixes: b685d3d6
Cc: stable@vger.kernel.org # 4.9+
CC: Jaegeuk Kim <jaegeuk@kernel.org>
CC: linux-f2fs-devel@lists.sourceforge.net
Signed-off-by: NJan Kara <jack@suse.cz>
Acked-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>