This patch introduces lifetime IO write statistics exposed to the sysfs interface.
The write IO amount is obtained from block layer, accumulated in the file system and
stored in the hot node summary of checkpoint.
Signed-off-by: Shuoran Liu <liushuoran@huawei.com>
Signed-off-by: Pengyang Hou <houpengyang@huawei.com>
[Jaegeuk Kim: add sysfs documentation]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
On the worst case, we need to scan the whole radix tree and every rb-tree to
free the victimed extent_nodes when shrinking.
Pengyang initially introduced a victim_list to record the victimed extent_nodes,
and free these extent_nodes by just scanning a list.
Later, Chao Yu enhances the original patch to improve memory footprint by
removing victim list.
The policy of lru list shrinking becomes:
1) lock lru list's lock
2) trylock extent tree's lock
3) remove extent node from lru list
4) unlock lru list's lock
5) do shrink
6) repeat 1) to 5)
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
There are three steps to free an extent node:
1) list_del_init, 2)__detach_extent_node, 3) kmem_cache_free
In path f2fs_destroy_extent_tree, 1->2->3 to free a node,
But in path f2fs_update_extent_tree_range, it is 2->1->3.
This patch makes all the order to be: 1->2->3
It makes sense, since in the next patch, we import a victim list in the
path shrink_extent_tree, we could check if the extent_node is in the victim
list by checking the list_empty(). So it is necessary to put 1) first.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
variable nsearched in get_victim_by_default() indicates the number of
dirty segments we already checked. There are 2 problems about the way
it updates:
1. When p.ofs_unit is greater than 1, the victim we find consists
of multiple segments, possibly more than 1 dirty segment.
But nsearched always increases by 1.
2. If segments have been found but not been chosen, nsearched won't
increase. So even we have checked all dirty segments, nsearched
may still less than p.max_search.
All these problems could cause unnecessary search after all dirty
segments have already been checked.
Signed-off-by: Fan li <fanofcode.li@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
no need to wait inline file page writeback for no one
use it, so this patch delete unnecessary wait.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In write_begin, if storage supports stable_page, we don't need to wait for
writeback to update its contents.
This patch introduces to use wait_for_stable_page instead of
wait_on_page_writeback.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If we configure section consist of multiple segments, foreground GC will
do the garbage collection with following approach:
for each segment in victim section
blk_start_plug
for each valid block in segment
write out by OPU method
submit bio cache <---
blk_finish_plug <---
There are two issue:
1) for most of the time, 'submit bio cache' will break the merging in
current bio buffer from writes of next segments, making a smaller bio
submitting.
2) block plug only cover IO submitting in one segment, which reduce
opportunity of merging IOs in plug with multiple segments.
So refactor the code as below structure to strive for biggest
opportunity of merging IOs:
blk_start_plug
for each segment in victim section
for each valid block in segment
write out by OPU method
submit bio cache
blk_finish_plug
Test method:
1. mkfs.f2fs -s 8 /dev/sdX
2. touch 32 files
3. write 2M data into each file
4. punch 1.5M data from offset 0 for each file
5. trigger foreground gc through ioctl
Before patch, there are totoally 40 bios submitted.
f2fs_submit_write_bio: dev = (8,32), WRITE_SYNC, DATA, sector = 65536, size = 122880
f2fs_submit_write_bio: dev = (8,32), WRITE_SYNC, DATA, sector = 65776, size = 122880
f2fs_submit_write_bio: dev = (8,32), WRITE_SYNC, DATA, sector = 66016, size = 122880
f2fs_submit_write_bio: dev = (8,32), WRITE_SYNC, DATA, sector = 66256, size = 122880
f2fs_submit_write_bio: dev = (8,32), WRITE_SYNC, DATA, sector = 66496, size = 32768
----repeat for 8 times
After patch, there are totally 35 bios submitted.
f2fs_submit_write_bio: dev = (8,32), WRITE_SYNC, DATA, sector = 65536, size = 122880
----repeat 34 times
f2fs_submit_write_bio: dev = (8,32), WRITE_SYNC, DATA, sector = 73696, size = 16384
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If end_io gets an error, we don't need to set the page as dirty, since we
already set f2fs_stop_checkpoint which will not flush any data.
This will resolve the following warning.
======================================================
[ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]
4.4.0+ #9 Tainted: G O
------------------------------------------------------
xfs_io/26773 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
(&(&sbi->inode_lock[i])->rlock){+.+...}, at: [<ffffffffc025483f>] update_dirty_page+0x6f/0xd0 [f2fs]
and this task is already holding:
(&(&q->__queue_lock)->rlock){-.-.-.}, at: [<ffffffff81396ea2>] blk_queue_bio+0x422/0x490
which would create a new lock dependency:
(&(&q->__queue_lock)->rlock){-.-.-.} -> (&(&sbi->inode_lock[i])->rlock){+.+...}
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In write_begin, if there is an inline_data, f2fs loads it into 0'th data page.
Since it's the read path, we don't need to sync its inode page.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In write_end, we don't need to sync inode page at every time.
Instead, we can expect f2fs_write_inode will update later.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The sceanrio is:
1. create fully node blocks
2. flush node blocks
3. write inline_data for all the node blocks again
4. flush node blocks redundantly
So, this patch tries to flush inline_data when flushing node blocks.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The scenario is:
1. create lots of node blocks
2. sync
3. write lots of inline_data
-> got panic due to no free space
In that case, we should flush node blocks when writing inline_data in #3,
and trigger gc as well.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If there are many writepages calls by multiple threads in background, we don't
need to serialize to merge all the bios, since it's background.
In such the case, it'd better to run writepages concurrently.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
get_new_segment starts from current segment position, tries to search a
free segment among its right neighbors locate in same section.
But previously our search area was set as [current segment, max segment],
which means we have to search to more bits in free_segmap bitmap for some
worse cases. So here we correct the search area to [current segment, last
segment in section] to avoid unnecessary searching.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch exports a new sysfs entry 'dirty_nat_ratio' to control threshold
of dirty nat entries, if current ratio exceeds configured threshold,
checkpoint will be triggered in f2fs_balance_fs_bg for flushing dirty nats.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When testing f2fs with xfstest, generic/251 is stuck for long time,
the case uses below serials to obtain fresh released space in device,
in order to prepare for following fstrim test.
1. rm -rf /mnt/dir
2. mkdir /mnt/dir/
3. cp -axT `pwd`/ /mnt/dir/
4. goto 1
During preparing step, all nat entries will be cached in nat cache,
most of them are dirty entries with invalid blkaddr, which means
nodes related to these entries have been truncated, and they could
be reused after the dirty entries been checkpointed.
However, there was no checkpoint been triggered, so nid allocators
(e.g. mkdir, creat) will run into long journey of iterating all NAT
pages, looking for free nids in alloc_nid->build_free_nids.
Here, in f2fs_balance_fs_bg we give another chance to do checkpoint
to flush nat entries for reusing them in free nid cache when dirty
entry count exceeds 10% of max count.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Operations in is_merged_page is related to inner bio cache, move it to
data.c.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Currently we maintain perfect LRU list by moving entry to the tail of
the list when it gets used. However these operations on cache-global
list are relatively expensive.
In this patch we switch to lazy updates of LRU list. Whenever entry gets
used, we set a referenced bit in it. When reclaiming entries, we give
referenced entries another round in the LRU. Since the list is not a
real LRU anymore, rename it to just 'list'.
In my testing this logic gives about 30% boost to workloads with mostly
unique xattr blocks (e.g. xattr-bench with 10 files and 10000 unique
xattr values).
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* multipath:
NFS add callback_ops to nfs4_proc_bind_conn_to_session_callback
pnfs/NFSv4.1: Add multipath capabilities to pNFS flexfiles servers over NFSv3
SUNRPC: Allow addition of new transports to a struct rpc_clnt
NFSv4.1: nfs4_proc_bind_conn_to_session must iterate over all connections
SUNRPC: Make NFS swap work with multipath
SUNRPC: Add a helper to apply a function to all the rpc_clnt's transports
SUNRPC: Allow caller to specify the transport to use
SUNRPC: Use the multipath iterator to assign a transport to each task
SUNRPC: Make rpc_clnt store the multipath iterators
SUNRPC: Add a structure to track multiple transports
SUNRPC: Make freeing of struct xprt rcu-safe
SUNRPC: Uninline xprt_get(); It isn't performance critical.
SUNRPC: Reorder rpc_task to put waitqueue related info in same cachelines
SUNRPC: Remove unused function rpc_task_reset_client
* nfsv41_cb:
NFSv4.x: Fix NFS4ERR_RETRY_UNCACHED_REP in nfs4_callback_sequence
NFSv4.x: Allow multiple callbacks in flight
NFSv4.x: Fix wraparound issues when validing the callback sequence id
NFSv4.x: Enforce the ca_maxresponsesize_cached on the back channel
NFSv4.x: CB_SEQUENCE should return NFS4ERR_DELAY if still executing
NFSv4.x: Remove hard coded slotids in callback channel
Replace another case where the layout 'plh_block_lgets' can trigger
infinite loops in send_layoutget().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the server reboots while there is a layoutget outstanding, then
the call to pnfs_choose_layoutget_stateid() will fail with an EAGAIN
error, which causes an infinite loop in send_layoutget(). The reason
why we never break out of the loop is that the layout 'plh_block_lgets'
field is never cleared.
Fix is to replace plh_block_lgets with NFS_LAYOUT_INVALID_STID, which
can be reset after a new layoutget.
Fixes: ab7d763e47 ("pNFS: Ensure nfs4_layoutget_prepare returns...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This patch fixes the problems with patch b3a5bbfd7.
1. It removes a return statement from lowcomms_error_report
because it needs to call the original error report in all paths
through the function.
2. All socket callbacks are saved and restored, not just the
sk_error_report, and that's done so with proper locking like
sunrpc does.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch replaces the call to nodeid_to_addr with a call to
kernel_getpeername. This avoids taking a spinlock because it may
potentially be called from a softirq context.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
So far number of entries in mbcache is limited only by the pressure from
the shrinker. Since too many entries degrade the hash table and
generally we expect that caching more entries has diminishing returns,
limit number of entries the same way as in the old mbcache to 16 * hash
table size.
Once we exceed the desired maximum number of entries, we schedule a
backround work to reclaim entries. If the background work cannot keep up
and the number of entries exceeds two times the desired maximum, we
reclaim some entries directly when allocating a new entry.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Both ext2 and ext4 are now converted to mbcache2. Remove the old mbcache
code.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The conversion is generally straightforward. We convert filesystem from
a global cache to per-fs one. Similarly to ext4 the tricky part is that
xattr block corresponding to found mbcache entry can get freed before we
get buffer lock for that block. So we have to check whether the entry is
still valid after getting the buffer lock.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The conversion is generally straightforward. The only tricky part is
that xattr block corresponding to found mbcache entry can get freed
before we get buffer lock for that block. So we have to check whether
the entry is still valid after getting buffer lock.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Original mbcache was designed to have more features than what ext?
filesystems ended up using. It supported entry being in more hashes, it
had a home-grown rwlocking of each entry, and one cache could cache
entries from multiple filesystems. This genericity also resulted in more
complex locking, larger cache entries, and generally more code
complexity.
This is reimplementation of the mbcache functionality to exactly fit the
purpose ext? filesystems use it for. Cache entries are now considerably
smaller (7 instead of 13 longs), the code is considerably smaller as
well (414 vs 913 lines of code), and IMO also simpler. The new code is
also much more lightweight.
I have measured the speed using artificial xattr-bench benchmark, which
spawns P processes, each process sets xattr for F different files, and
the value of xattr is randomly chosen from a pool of V values. Averages
of runtimes for 5 runs for various combinations of parameters are below.
The first value in each cell is old mbache, the second value is the new
mbcache.
V=10
F\P 1 2 4 8 16 32 64
10 0.158,0.157 0.208,0.196 0.500,0.277 0.798,0.400 3.258,0.584 13.807,1.047 61.339,2.803
100 0.172,0.167 0.279,0.222 0.520,0.275 0.825,0.341 2.981,0.505 12.022,1.202 44.641,2.943
1000 0.185,0.174 0.297,0.239 0.445,0.283 0.767,0.340 2.329,0.480 6.342,1.198 16.440,3.888
V=100
F\P 1 2 4 8 16 32 64
10 0.162,0.153 0.200,0.186 0.362,0.257 0.671,0.496 1.433,0.943 3.801,1.345 7.938,2.501
100 0.153,0.160 0.221,0.199 0.404,0.264 0.945,0.379 1.556,0.485 3.761,1.156 7.901,2.484
1000 0.215,0.191 0.303,0.246 0.471,0.288 0.960,0.347 1.647,0.479 3.916,1.176 8.058,3.160
V=1000
F\P 1 2 4 8 16 32 64
10 0.151,0.129 0.210,0.163 0.326,0.245 0.685,0.521 1.284,0.859 3.087,2.251 6.451,4.801
100 0.154,0.153 0.211,0.191 0.276,0.282 0.687,0.506 1.202,0.877 3.259,1.954 8.738,2.887
1000 0.145,0.179 0.202,0.222 0.449,0.319 0.899,0.333 1.577,0.524 4.221,1.240 9.782,3.579
V=10000
F\P 1 2 4 8 16 32 64
10 0.161,0.154 0.198,0.190 0.296,0.256 0.662,0.480 1.192,0.818 2.989,2.200 6.362,4.746
100 0.176,0.174 0.236,0.203 0.326,0.255 0.696,0.511 1.183,0.855 4.205,3.444 19.510,17.760
1000 0.199,0.183 0.240,0.227 1.159,1.014 2.286,2.154 6.023,6.039 ---,10.933 ---,36.620
V=100000
F\P 1 2 4 8 16 32 64
10 0.171,0.162 0.204,0.198 0.285,0.230 0.692,0.500 1.225,0.881 2.990,2.243 6.379,4.771
100 0.151,0.171 0.220,0.210 0.295,0.255 0.720,0.518 1.226,0.844 3.423,2.831 19.234,17.544
1000 0.192,0.189 0.249,0.225 1.162,1.043 2.257,2.093 5.853,4.997 ---,10.399 ---,32.198
We see that the new code is faster in pretty much all the cases and
starting from 4 processes there are significant gains with the new code
resulting in upto 20-times shorter runtimes. Also for large numbers of
cached entries all values for the old code could not be measured as the
kernel started hitting softlockups and died before the test completed.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In commit bcff24887d ("ext4: don't read blocks from disk after extents
being swapped") bh is not updated correctly in the for loop and wrong
data has been written to disk. generic/324 catches this on sub-page
block size ext4.
Fixes: bcff24887d ("ext4: don't read blocks from disk after extentsbeing swapped")
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Now, ext4_free_blocks() doesn't revoke data blocks of per-file data
journalled inode and it can cause file data inconsistency problems.
Even though data blocks of per-file data journalled inode are already
forgotten by jbd2_journal_invalidatepage() in advance of invoking
ext4_free_blocks(), we still need to revoke the data blocks here.
Moreover some of the metadata blocks, which are not found by
sb_find_get_block(), are still needed to be revoked, but this is also
missing here.
Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
This patch defines kernel_read_file_from_path(), a wrapper for the VFS
common kernel_read_file().
Changelog:
- revert error msg regression - reported by Sergey Senozhatsky
- Separated from the IMA patch
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Pull x86 fixes from Ingo Molnar:
"This is unusually large, partly due to the EFI fixes that prevent
accidental deletion of EFI variables through efivarfs that may brick
machines. These fixes are somewhat involved to maintain compatibility
with existing install methods and other usage modes, while trying to
turn off the 'rm -rf' bricking vector.
Other fixes are for large page ioremap()s and for non-temporal
user-memcpy()s"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix vmalloc_fault() to handle large pages properly
hpet: Drop stale URLs
x86/uaccess/64: Handle the caching of 4-byte nocache copies properly in __copy_user_nocache()
x86/uaccess/64: Make the __copy_user_nocache() assembly code more readable
lib/ucs2_string: Correct ucs2 -> utf8 conversion
efi: Add pstore variables to the deletion whitelist
efi: Make efivarfs entries immutable by default
efi: Make our variable validation list include the guid
efi: Do variable name validation tests in utf8
efi: Use ucs2_as_utf8 in efivarfs instead of open coding a bad version
lib/ucs2_string: Add ucs2 -> utf8 helper functions
propagate_one(m) calculates "type" argument for copy_tree() like this:
> if (m->mnt_group_id == last_dest->mnt_group_id) {
> type = CL_MAKE_SHARED;
> } else {
> type = CL_SLAVE;
> if (IS_MNT_SHARED(m))
> type |= CL_MAKE_SHARED;
> }
The "type" argument then governs clone_mnt() behavior with respect to flags
and mnt_master of new mount. When we iterate through a slave group, it is
possible that both current "m" and "last_dest" are not shared (although,
both are slaves, i.e. have non-NULL mnt_master-s). Then the comparison
above erroneously makes new mount shared and sets its mnt_master to
last_source->mnt_master. The patch fixes the problem by handling zero
mnt_group_id-s as though they are unequal.
The similar problem exists in the implementation of "else" clause above
when we have to ascend upward in the master/slave tree by calling:
> last_source = last_source->mnt_master;
> last_dest = last_source->mnt_parent;
proper number of times. The last step is governed by
"n->mnt_group_id != last_dest->mnt_group_id" condition that may lie if
both are zero. The patch fixes this case in the same way as the former one.
[AV: don't open-code an obvious helper...]
Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
It forgets kunmap() on a failure exit, but there's really no point keeping
the page kmapped at all - after all, what we are doing is a bunch of memcpy()
into the parts of page, so kmap_atomic()/kunmap_atomic() just around those
memcpy() is enough.
Spotted-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The code could leak xattrs->lock on error.
Problem introduced with 786534b92f "tmpfs: listxattr should
include POSIX ACL xattrs".
Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The user-visible impact of the issue is for example that without this
patch sensors-detect breaks when trying to seek in /dev/cpu/0/cpuid.
'~0ULL' is a 'unsigned long long' that when converted to a loff_t,
which is signed, gets turned into -1. later in vfs_setpos we have
'if (offset > maxsize)', which makes it always return EINVAL.
Fixes: b25472f9b9 ("new helpers: no_seek_end_llseek{,_size}()")
Signed-off-by: Wouter van Kesteren <woutershep@gmail.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull ext4 bugfixes from Ted Ts'o:
"Miscellaneous ext4 bug fixes for v4.5"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix crashes in dioread_nolock mode
ext4: fix bh->b_state corruption
ext4: fix memleak in ext4_readdir()
ext4: remove unused parameter "newblock" in convert_initialized_extent()
ext4: don't read blocks from disk after extents being swapped
ext4: fix potential integer overflow
ext4: add a line break for proc mb_groups display
ext4: ioctl: fix erroneous return value
ext4: fix scheduling in atomic on group checksum failure
ext4 crypto: move context consistency check to ext4_file_open()
ext4 crypto: revalidate dentry after adding or removing the key
Pull btrfs fix from Chris Mason:
"My for-linus-4.5 branch has a btrfs DIO error passing fix.
I know how much you love DIO, so I'm going to suggest against reading
it. We'll follow up with a patch to drop the error arg from
dio_end_io in the next merge window."
* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix direct IO requests not reporting IO error to user space
Merge fixes from Andrew Morton:
"10 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: slab: free kmem_cache_node after destroy sysfs file
ipc/shm: handle removed segments gracefully in shm_mmap()
MAINTAINERS: update Kselftest Framework mailing list
devm_memremap_release(): fix memremap'd addr handling
mm/hugetlb.c: fix incorrect proc nr_hugepages value
mm, x86: fix pte_page() crash in gup_pte_range()
fsnotify: turn fsnotify reaper thread into a workqueue job
Revert "fsnotify: destroy marks with call_srcu instead of dedicated thread"
mm: fix regression in remap_file_pages() emulation
thp, dax: do not try to withdraw pgtable from non-anon VMA
