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>

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 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>

-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>

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>

This patch adds an entry in f2fs/status to show # of available nids.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch flushes dirty nats in order to acquire available nids by writing
checkpoint. Otherwise, we can have no chance to get freed nids.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Introduce CP_TRIMMED_FLAG to indicate all invalid block were trimmed
before umount, so once we do mount with image which contain the flag,
we don't record invalid blocks as undiscard one, when fstrim is being
triggered, we can avoid issuing redundant discard commands.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Change to use different bits of cpc->reason to indicate different status,
so cpc->reason can indicate more than one reason.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We don't need to rewrite the page under cp_rwsem and dnode locks.
Signed-off-by: NHou Pengyang <houpengyang@huawei.com>
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In order to shrink size of struct discard_cmd, change variable type of
@state in struct discard_cmd from int to unsigned char.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Previously, with protection of cmd_lock, we will wait for end io of
discard command which potentially may lead long latency, making worse
concurrency.

So, in this patch, we try to add reference into discard entry to prevent
the entry being released by other thread, then we can avoid holding
global cmd_lock during waiting discard to finish.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This makes sure each write request has nullified encrypted_page pointer.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

F2FS uses 4 bytes to represent block address. As a result, supported
size of disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
Signed-off-by: NJin Qian <jinqian@google.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces valid_ipu_blkaddr to clean up checking block address for
inplace-update.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If a page is cold, NOT atomit written and need_ipu now, there is
a high probability that IPU should be adapted. For IPU, we try to
check extent tree to get the block index first, instead of reading
the dnode page, where may lead to an useless dnode IO, since no need to
update the dnode index for IPU.
Signed-off-by: NHou Pengyang <houpengyang@huawei.com>
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces encrypt_one_page which encrypts one data page before
submit_bio, and change the use of need_inplace_update.
Signed-off-by: NHou Pengyang <houpengyang@huawei.com>
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Just cleanup, no logic change.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Just cleanup, no logic change.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch start to enable 4K granularity small discard by default
when realtime discard is on, so, in seriously fragmented space,
small size discard can be issued in time to avoid useless storage
space occupying of invalid filesystem's data, then performance of
flash storage can be recovered.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

It's better to delay awaking discard thread while queuing discard commands
in checkpoint, it will help to give more chances for merging big and small
discard.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch seperate nat page read io from nat_tree_lock.

-lock_page
	-get_node_info()
		-current_nat_addr

			......           	->       write_checkpoint

			-get_meta_page

Because we lock node page, we can make sure no other threads
modify this nid concurrently. So we just obtain current_nat_addr
under nat_tree_lock, node info is always same in both nat pack.
Signed-off-by: NYunlei He <heyunlei@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Commit 88c5c13a (f2fs: fix multiple f2fs_add_link() calls having
same name) does not cover the scenario where inline dentry is enabled.
In that case, F2FS_I(dir)->task will be NULL, and __f2fs_add_link will
lookup dentries one more time.

This patch fixes it by moving the assigment of current task to a upper
level to cover both normal and inline dentry.

Cc: <stable@vger.kernel.org>
Fixes: 88c5c13a (f2fs: fix multiple f2fs_add_link() calls having same name)
Signed-off-by: NSheng Yong <shengyong1@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Async request may be throttled in block layer, so page for async may keep WRITE_BACK
for a long time.

For encrytped inode, we need wait on page writeback no matter if the device supports
BDI_CAP_STABLE_WRITES. This may result in a higher waiting page writeback time for
async encrypted inode page.

This patch skips IPU for encrypted inode's updating write.
Signed-off-by: NHou Pengyang <houpengyang@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch also reverts d0db7703 ("f2fs: do SSR in higher priority").

This patch fixes out of free segments caused by many small file creation by
1) mkfs -s 1 2G
2) mount
3) untar
 - preoduce 60000 small files burstly
4) sync
 - flush node pages
 - flush imeta

Here, when we do f2fs_balance_fs, we missed # of imeta blocks, resulting in
skipping to check has_not_enough_free_secs.

Another test is done by
1) mkfs -s 12 2G
2) mount
3) untar
 - preoduce 60000 small files burstly
4) sync
 - flush node pages
 - flush imeta

In this case, this patch also fixes wrong block allocation under large section
size.
Reported-by: NWilliam Brana <wbrana@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

With a recent addition of f2fs_lookup_extent_tree(), we get a warning about
the use of empty macros:

fs/f2fs/extent_cache.c: In function 'f2fs_lookup_extent_tree':
fs/f2fs/extent_cache.c:358:32: error: suggest braces around empty body in an 'else' statement [-Werror=empty-body]
   stat_inc_rbtree_node_hit(sbi);

A good way to avoid the warning and make the code more robust is to define
all no-op macros as 'do { } while (0)'.

Fixes: 54c2258c ("f2fs: extract rb-tree operation infrastructure")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reivewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch gives slower device region to warm/cold data area more eagerly.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fixes wrong _IOW usage.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds an ioctl to flush data in faster device to cold area. User can
give device number and number of segments to move. It doesn't move it if there
is only one device.

The parameter looks like:

struct f2fs_flush_device {
	u32 dev_num;		/* device number to flush */
	u32 segments;		/* # of segments to flush */
};
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces an ASYNC IPU policy.

Under senario of large # of async updating(e.g. log writing in Android),
disk would be seriously fragmented, and higher frequent gc would be triggered.

This patch uses IPU to rewrite the async update writting, since async is
NOT sensitive to io latency.
Signed-off-by: NHou Pengyang <houpengyang@huawei.com>

This patch adds to account undiscard blocks.
Signed-off-by: NChao Yu <yuchao0@huawei.com>

For IPU writes, there won't be any udpates in dnode page since we
will reuse old block address instead of allocating new one, so we
don't need to lock cp_rwsem during IPU IO submitting.
Signed-off-by: NChao Yu <yuchao0@huawei.com>

Introduce __check_rb_tree_consistence to check consistence of rb-tree
based discard cache in runtime.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Add an even class f2fs_discard for introducing f2fs_queue_discard, then
use f2fs_{queue,issue}_discard to trace __{queue,submit}_discard_cmd.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Keep issuing big size discard in prior instead of the one with random
size, so that we expect that it will help to:
- be quick to recycle unused large space in flash storage device.
- give a chance for
  a) wait to merge small piece discards into bigger one, or
  b) avoid issuing discards while they have being reallocated by SSR.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Avoid long variable name in discard_cmd_control structure, no logic
change.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Introduce rb-tree based discard cache infrastructure to speed up lookup and
merge operation of discard entry.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: initialize dc to avoid build warning]
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In the check_only mode, we should not make any dirty node pages. Otherwise,
we can get this panic:

F2FS-fs (nvme0n1p1): Need to recover fsync data
------------[ cut here ]------------
kernel BUG at fs/f2fs/node.c:2204!
CPU: 7 PID: 19923 Comm: mount Tainted: G           OE   4.9.8 #2
RIP: 0010:[<ffffffffc0979c0b>]  [<ffffffffc0979c0b>] flush_nat_entries+0x43b/0x7d0 [f2fs]
Call Trace:
 [<ffffffffc096ddaa>] ? __f2fs_submit_merged_bio+0x5a/0xd0 [f2fs]
 [<ffffffffc096ddaa>] ? __f2fs_submit_merged_bio+0x5a/0xd0 [f2fs]
 [<ffffffffc096dddb>] ? __f2fs_submit_merged_bio+0x8b/0xd0 [f2fs]
 [<ffffffff860e450f>] ? up_write+0x1f/0x40
 [<ffffffffc096dddb>] ? __f2fs_submit_merged_bio+0x8b/0xd0 [f2fs]
 [<ffffffffc0969f04>] write_checkpoint+0x2f4/0xf20 [f2fs]
 [<ffffffff860e938d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffffc0960bc9>] ? f2fs_sync_fs+0x79/0x190 [f2fs]
 [<ffffffffc0960bc9>] ? f2fs_sync_fs+0x79/0x190 [f2fs]
 [<ffffffffc0960bd5>] f2fs_sync_fs+0x85/0x190 [f2fs]
 [<ffffffffc097b6de>] f2fs_balance_fs_bg+0x7e/0x1c0 [f2fs]
 [<ffffffffc0977b64>] f2fs_write_node_pages+0x34/0x350 [f2fs]
 [<ffffffff860e5f42>] ? __lock_is_held+0x52/0x70
 [<ffffffff861d9b31>] do_writepages+0x21/0x30
 [<ffffffff86298ce1>] __writeback_single_inode+0x61/0x760
 [<ffffffff86909127>] ? _raw_spin_unlock+0x27/0x40
 [<ffffffff8629a735>] writeback_single_inode+0xd5/0x190
 [<ffffffff8629a889>] write_inode_now+0x99/0xc0
 [<ffffffff86283876>] iput+0x1f6/0x2c0
 [<ffffffffc0964b52>] f2fs_fill_super+0xc32/0x10c0 [f2fs]
 [<ffffffff86266462>] mount_bdev+0x182/0x1b0
 [<ffffffffc0963f20>] ? f2fs_commit_super+0x100/0x100 [f2fs]
 [<ffffffffc0960da5>] f2fs_mount+0x15/0x20 [f2fs]
 [<ffffffff86266e08>] mount_fs+0x38/0x170
 [<ffffffff86288bab>] vfs_kern_mount+0x6b/0x160
 [<ffffffff8628bcfe>] do_mount+0x1be/0xd60
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>