for ext4 encryption which provide better security and performance.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iQEcBAABCAAGBQJVRsVDAAoJEPL5WVaVDYGj/UUIAI6zLGhq3I8uQLZQC22Ew2Ph
TPj6eABDuTrB/7QpAu21Dk59N70MQpsBTES6yLWWLf/eHp0gsH7gCNY/C9185vOh
tQjzw18hRH2IfPftOBrjDlPGbbBD8Gu9jAmpm5kKKOtBuSVbKQ4GeN6BTECkgwlg
U5EJHJJ5Ahl4MalODFreOE5ZrVC7FWGEpc1y/MquQ0qcGSGlNd35leK5FE2bfHWZ
M1IJfXH5RRVPUBp26uNvzEg0TtpqkigmCJUT6gOVLfSYBw+lYEbGl4lCflrJmbgt
8EZh3Q0plsDbNhMzqSvOE4RvsOZ28oMjRNbzxkAaoz/FlatWX2hrfAoI2nqRrKg=
=Unbp
-----END PGP SIGNATURE-----
Merge tag 'for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Some miscellaneous bug fixes and some final on-disk and ABI changes
for ext4 encryption which provide better security and performance"
* tag 'for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix growing of tiny filesystems
ext4: move check under lock scope to close a race.
ext4: fix data corruption caused by unwritten and delayed extents
ext4 crypto: remove duplicated encryption mode definitions
ext4 crypto: do not select from EXT4_FS_ENCRYPTION
ext4 crypto: add padding to filenames before encrypting
ext4 crypto: simplify and speed up filename encryption
This patch removes duplicated encryption modes which were already in
ext4.h. They were duplicated from commit 3edc18d and commit f542fb.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This obscures the length of the filenames, to decrease the amount of
information leakage. By default, we pad the filenames to the next 4
byte boundaries. This costs nothing, since the directory entries are
aligned to 4 byte boundaries anyway. Filenames can also be padded to
8, 16, or 32 bytes, which will consume more directory space.
Change-Id: Ibb7a0fb76d2c48e2061240a709358ff40b14f322
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Avoid using SHA-1 when calculating the user-visible filename when the
encryption key is available, and avoid decrypting lots of filenames
when searching for a directory entry in a directory block.
Change-Id: If4655f144784978ba0305b597bfa1c8d7bb69e63
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull third hunk of vfs changes from Al Viro:
"This contains the ->direct_IO() changes from Omar + saner
generic_write_checks() + dealing with fcntl()/{read,write}() races
(mirroring O_APPEND/O_DIRECT into iocb->ki_flags and instead of
repeatedly looking at ->f_flags, which can be changed by fcntl(2),
check ->ki_flags - which cannot) + infrastructure bits for dhowells'
d_inode annotations + Christophs switch of /dev/loop to
vfs_iter_write()"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (30 commits)
block: loop: switch to VFS ITER_BVEC
configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode
VFS: Make pathwalk use d_is_reg() rather than S_ISREG()
VFS: Fix up debugfs to use d_is_dir() in place of S_ISDIR()
VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
NFS: Don't use d_inode as a variable name
VFS: Impose ordering on accesses of d_inode and d_flags
VFS: Add owner-filesystem positive/negative dentry checks
nfs: generic_write_checks() shouldn't be done on swapout...
ocfs2: use __generic_file_write_iter()
mirror O_APPEND and O_DIRECT into iocb->ki_flags
switch generic_write_checks() to iocb and iter
ocfs2: move generic_write_checks() before the alignment checks
ocfs2_file_write_iter: stop messing with ppos
udf_file_write_iter: reorder and simplify
fuse: ->direct_IO() doesn't need generic_write_checks()
ext4_file_write_iter: move generic_write_checks() up
xfs_file_aio_write_checks: switch to iocb/iov_iter
generic_write_checks(): drop isblk argument
blkdev_write_iter: expand generic_file_checks() call in there
...
Also add the test dummy encryption mode flag so we can more easily
test the encryption patches using xfstests.
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The original dax patchset split the ext2/4_file_operations because of the
two NULL splice_read/splice_write in the dax case.
In the vfs if splice_read/splice_write are NULL we then call
default_splice_read/write.
What we do here is make generic_file_splice_read aware of IS_DAX() so the
original ext2/4_file_operations can be used as is.
For write it appears that iter_file_splice_write is just fine. It uses
the regular f_op->write(file,..) or new_sync_write(file, ...).
Signed-off-by: Boaz Harrosh <boaz@plexistor.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For encrypted directories, we need to pass in a separate parameter for
the decrypted filename, since the directory entry contains the
encrypted filename.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
On encrypt, we will re-assign the buffer_heads to point to a bounce
page rather than the control_page (which is the original page to write
that contains the plaintext). The block I/O occurs against the bounce
page. On write completion, we re-assign the buffer_heads to the
original plaintext page.
On decrypt, we will attach a read completion callback to the bio
struct. This read completion will decrypt the read contents in-place
prior to setting the page up-to-date.
The current encryption mode, AES-256-XTS, lacks cryptographic
integrity. AES-256-GCM is in-plan, but we will need to devise a
mechanism for handling the integrity data.
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The rw parameter to direct_IO is redundant with iov_iter->type, and
treated slightly differently just about everywhere it's used: some users
do rw & WRITE, and others do rw == WRITE where they should be doing a
bitwise check. Simplify this with the new iov_iter_rw() helper, which
always returns either READ or WRITE.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This takes code from fs/mpage.c and optimizes it for ext4. Its
primary reason is to allow us to more easily add encryption to ext4's
read path in an efficient manner.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
and read-only images (for which the implementation is mostly just the
reserved code point for a read-only feature :-)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=PF+t
-----END PGP SIGNATURE-----
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Ext4 bug fixes.
We also reserved code points for encryption and read-only images (for
which the implementation is mostly just the reserved code point for a
read-only feature :-)"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix indirect punch hole corruption
ext4: ignore journal checksum on remount; don't fail
ext4: remove duplicate remount check for JOURNAL_CHECKSUM change
ext4: fix mmap data corruption in nodelalloc mode when blocksize < pagesize
ext4: support read-only images
ext4: change to use setup_timer() instead of init_timer()
ext4: reserve codepoints used by the ext4 encryption feature
jbd2: complain about descriptor block checksum errors
This is a port of the DAX functionality found in the current version of
ext2.
[matthew.r.wilcox@intel.com: heavily tweaked]
[akpm@linux-foundation.org: remap_pages went away]
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a rocompat feature, "readonly" to mark a FS image as read-only.
The feature prevents the kernel and e2fsprogs from changing the image;
the flag can be toggled by tune2fs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fixes, which should improve CPU utilization and potential soft lockups
under heavy memory pressure, and Eric Whitney's bigalloc fixes.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=ZrTc
-----END PGP SIGNATURE-----
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"Lots of bugs fixes, including Zheng and Jan's extent status shrinker
fixes, which should improve CPU utilization and potential soft lockups
under heavy memory pressure, and Eric Whitney's bigalloc fixes"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (26 commits)
ext4: ext4_da_convert_inline_data_to_extent drop locked page after error
ext4: fix suboptimal seek_{data,hole} extents traversial
ext4: ext4_inline_data_fiemap should respect callers argument
ext4: prevent fsreentrance deadlock for inline_data
ext4: forbid journal_async_commit in data=ordered mode
jbd2: remove unnecessary NULL check before iput()
ext4: Remove an unnecessary check for NULL before iput()
ext4: remove unneeded code in ext4_unlink
ext4: don't count external journal blocks as overhead
ext4: remove never taken branch from ext4_ext_shift_path_extents()
ext4: create nojournal_checksum mount option
ext4: update comments regarding ext4_delete_inode()
ext4: cleanup GFP flags inside resize path
ext4: introduce aging to extent status tree
ext4: cleanup flag definitions for extent status tree
ext4: limit number of scanned extents in status tree shrinker
ext4: move handling of list of shrinkable inodes into extent status code
ext4: change LRU to round-robin in extent status tree shrinker
ext4: cache extent hole in extent status tree for ext4_da_map_blocks()
ext4: fix block reservation for bigalloc filesystems
...
Currently ext4_inline_data_fiemap ignores requested arguments (start
and len) which may lead endless loop if start != 0. Also fix incorrect
extent length determination.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently we scan extent status trees of inodes until we reclaim nr_to_scan
extents. This can however require a lot of scanning when there are lots
of delayed extents (as those cannot be reclaimed).
Change shrinker to work as shrinkers are supposed to and *scan* only
nr_to_scan extents regardless of how many extents did we actually
reclaim. We however need to be careful and avoid scanning each status
tree from the beginning - that could lead to a situation where we would
not be able to reclaim anything at all when first nr_to_scan extents in
the tree are always unreclaimable. We remember with each inode offset
where we stopped scanning and continue from there when we next come
across the inode.
Note that we also need to update places calling __es_shrink() manually
to pass reasonable nr_to_scan to have a chance of reclaiming anything and
not just 1.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In this commit we discard the lru algorithm for inodes with extent
status tree because it takes significant effort to maintain a lru list
in extent status tree shrinker and the shrinker can take a long time to
scan this lru list in order to reclaim some objects.
We replace the lru ordering with a simple round-robin. After that we
never need to keep a lru list. That means that the list needn't be
sorted if the shrinker can not reclaim any objects in the first round.
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently extent status tree doesn't cache extent hole when a write
looks up in extent tree to make sure whether a block has been allocated
or not. In this case, we don't put extent hole in extent cache because
later this extent might be removed and a new delayed extent might be
added back. But it will cause a defect when we do a lot of writes. If
we don't put extent hole in extent cache, the following writes also need
to access extent tree to look at whether or not a block has been
allocated. It brings a cache miss. This commit fixes this defect.
Also if the inode doesn't have any extent, this extent hole will be
cached as well.
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
For bigalloc filesystems we have to check whether newly requested inode
block isn't already part of a cluster for which we already have delayed
allocation reservation. This check happens in ext4_ext_map_blocks() and
that function sets EXT4_MAP_FROM_CLUSTER if that's the case. However if
ext4_da_map_blocks() finds in extent cache information about the block,
we don't call into ext4_ext_map_blocks() and thus we always end up
getting new reservation even if the space for cluster is already
reserved. This results in overreservation and premature ENOSPC reports.
Fix the problem by checking for existing cluster reservation already in
ext4_da_map_blocks(). That simplifies the logic and actually allows us
to get rid of the EXT4_MAP_FROM_CLUSTER flag completely.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
CC: linux-ext4@vger.kernel.org
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Convert the ext4_has_group_desc_csum predicate to look for a checksum
driver instead of the metadata_csum flag and change the bg checksum
calculation function to look for GDT_CSUM before taking the crc16
path.
Without this patch, if we mount with ^uninit_bg,^metadata_csum and
later metadata_csum gets turned on by accident, the block group
checksum functions will incorrectly assume that checksumming is
enabled (metadata_csum) but that crc16 should be used
(!s_chksum_driver). This is totally wrong, so fix the predicate
and the checksum formula selection.
(Granted, if the metadata_csum feature bit gets enabled on a live FS
then something underhanded is going on, but we could at least avoid
writing garbage into the on-disk fields.)
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: stable@vger.kernel.org
Besides the fact that this replacement improves code readability
it also protects from errors caused direct EXT4_S(sb)->s_es manipulation
which may result attempt to use uninitialized csum machinery.
#Testcase_BEGIN
IMG=/dev/ram0
MNT=/mnt
mkfs.ext4 $IMG
mount $IMG $MNT
#Enable feature directly on disk, on mounted fs
tune2fs -O metadata_csum $IMG
# Provoke metadata update, likey result in OOPS
touch $MNT/test
umount $MNT
#Testcase_END
# Replacement script
@@
expression E;
@@
- EXT4_HAS_RO_COMPAT_FEATURE(E, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
+ ext4_has_metadata_csum(E)
https://bugzilla.kernel.org/show_bug.cgi?id=82201
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
If there is a corrupted file system which has directory entries that
point at reserved, metadata inodes, prohibit them from being used by
treating them the same way we treat Boot Loader inodes --- that is,
mark them to be bad inodes. This prohibits them from being opened,
deleted, or modified via chmod, chown, utimes, etc.
In particular, this prevents a corrupted file system which has a
directory entry which points at the journal inode from being deleted
and its blocks released, after which point Much Hilarity Ensues.
Reported-by: Sami Liedes <sami.liedes@iki.fi>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
MAXQUOTAS value defines maximum number of quota types VFS supports.
This isn't necessarily the number of types ext4 supports. Although
ext4 will support project quotas, use ext4 private definition for
consistency with other filesystems.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Having done a full regression test, we can now drop the
DELALLOC_RESERVED state flag.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
This commit adds some statictics in extent status tree shrinker. The
purpose to add these is that we want to collect more details when we
encounter a stall caused by extent status tree shrinker. Here we count
the following statictics:
stats:
the number of all objects on all extent status trees
the number of reclaimable objects on lru list
cache hits/misses
the last sorted interval
the number of inodes on lru list
average:
scan time for shrinking some objects
the number of shrunk objects
maximum:
the inode that has max nr. of objects on lru list
the maximum scan time for shrinking some objects
The output looks like below:
$ cat /proc/fs/ext4/sda1/es_shrinker_info
stats:
28228 objects
6341 reclaimable objects
5281/631 cache hits/misses
586 ms last sorted interval
250 inodes on lru list
average:
153 us scan time
128 shrunk objects
maximum:
255 inode (255 objects, 198 reclaimable)
125723 us max scan time
If the lru list has never been sorted, the following line will not be
printed:
586ms last sorted interval
If there is an empty lru list, the following lines also will not be
printed:
250 inodes on lru list
...
maximum:
255 inode (255 objects, 198 reclaimable)
0 us max scan time
Meanwhile in this commit a new trace point is defined to print some
details in __ext4_es_shrink().
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Drop EXT4_EX_NOFREE_ON_ERR from ext4_ext_create_new_leaf(),
ext4_split_extent(), ext4_convert_unwritten_extents_endio().
This requires fixing all of their callers to potentially
ext4_ext_find_extent() to free the struct ext4_ext_path object in case
of an error, and there are interlocking dependencies all the way up to
ext4_ext_map_blocks(), ext4_swap_extents(), and
ext4_ext_remove_space().
Once this is done, we can drop the EXT4_EX_NOFREE_ON_ERR flag since it
is no longer necessary.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Right now, there are a places where it is all to easy to leak memory
on an error path, via a usage like this:
struct ext4_ext_path *path = NULL
while (...) {
...
path = ext4_ext_find_extent(inode, block, path, 0);
if (IS_ERR(path)) {
/* oops, if path was non-NULL before the call to
ext4_ext_find_extent, we've leaked it! :-( */
...
return PTR_ERR(path);
}
...
}
Unfortunately, there some code paths where we are doing the following
instead:
path = ext4_ext_find_extent(inode, block, orig_path, 0);
and where it's important that we _not_ free orig_path in the case
where ext4_ext_find_extent() returns an error.
So change the function signature of ext4_ext_find_extent() so that it
takes a struct ext4_ext_path ** for its third argument, and by
default, on an error, it will free the struct ext4_ext_path, and then
zero out the struct ext4_ext_path * pointer. In order to avoid
causing problems, we add a flag EXT4_EX_NOFREE_ON_ERR which causes
ext4_ext_find_extent() to use the original behavior of forcing the
caller to deal with freeing the original path pointer on the error
case.
The goal is to get rid of EXT4_EX_NOFREE_ON_ERR entirely, but this
allows for a gentle transition and makes the patches easier to verify.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Commit b8a8684502 introduced an accidental flag aliasing between
EXT4_EX_NOCACHE and EXT4_GET_BLOCKS_CONVERT_UNWRITTEN.
Fortunately, this didn't introduce any untorward side effects --- we
got lucky. Nevertheless, fix this and leave a warning to hopefully
avoid this from happening in the future.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_move_extents is too complex for review. It has duplicate almost
each function available in the rest of other codebase. It has useless
artificial restriction orig_offset == donor_offset. But in fact logic
of ext4_move_extents is very simple:
Iterate extents one by one (similar to ext4_fill_fiemap_extents)
->Iterate each page covered extent (similar to generic_perform_write)
->swap extents for covered by page (can be shared with IOC_MOVE_DATA)
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This allows us to make mext_next_extent static and potentially get rid
of it.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If we run into some kind of error, such as ENOMEM, while calling
ext4_getblk() or ext4_dx_find_entry(), we need to make sure this error
gets propagated up to ext4_find_entry() and then to its callers. This
way, transient errors such as ENOMEM can get propagated to the VFS.
This is important so that the system calls return the appropriate
error, and also so that in the case of ext4_lookup(), we return an
error instead of a NULL inode, since that will result in a negative
dentry cache entry that will stick around long past the OOM condition
which caused a transient ENOMEM error.
Google-Bug-Id: #17142205
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Before converting an inline directory to a regular directory, check
the directory entries to make sure they're not obviously broken.
This helps us to avoid a BUG_ON if one of the dirents is trashed.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Now ext4_has_inline_data() is used in wide spread codepaths. So we need
to make it as a inline function to avoid burning some CPU cycles.
Change in text size:
text data bss dec hex filename
before: 326110 19258 5528 350896 55ab0 fs/ext4/ext4.o
after: 326227 19258 5528 351013 55b25 fs/ext4/ext4.o
I use the following script to measure the CPU usage.
#!/bin/bash
shm_base='/dev/shm'
img=${shm_base}/ext4-img
mnt=/mnt/loop
e2fsprgs_base=$HOME/e2fsprogs
mkfs=${e2fsprgs_base}/misc/mke2fs
fsck=${e2fsprgs_base}/e2fsck/e2fsck
sudo umount $mnt
dd if=/dev/zero of=$img bs=4k count=3145728
${mkfs} -t ext4 -O inline_data -F $img
sudo mount -t ext4 -o loop $img $mnt
# start testing...
testdir="${mnt}/testdir"
mkdir $testdir
cd $testdir
echo "start testing..."
for ((cnt=0;cnt<100;cnt++)); do
for ((i=0;i<5;i++)); do
for ((j=0;j<5;j++)); do
for ((k=0;k<5;k++)); do
for ((l=0;l<5;l++)); do
mkdir -p $i/$j/$k/$l
echo "$i-$j-$k-$l" > $i/$j/$k/$l/testfile
done
done
done
done
ls -R $testdir > /dev/null
rm -rf $testdir/*
done
The result of `perf top -G -U` is as below.
vanilla:
13.92% [ext4] [k] ext4_do_update_inode
9.36% [ext4] [k] __ext4_get_inode_loc
4.07% [ext4] [k] ftrace_define_fields_ext4_writepages
3.83% [ext4] [k] __ext4_handle_dirty_metadata
3.42% [ext4] [k] ext4_get_inode_flags
2.71% [ext4] [k] ext4_mark_iloc_dirty
2.46% [ext4] [k] ftrace_define_fields_ext4_direct_IO_enter
2.26% [ext4] [k] ext4_get_inode_loc
2.22% [ext4] [k] ext4_has_inline_data
[...]
After applied the patch, we don't see ext4_has_inline_data() because it
has been inlined and perf couldn't sample it. Although it doesn't mean
that the CPU cycles can be saved but at least the overhead of function
calls can be eliminated. So IMHO we'd better inline this function.
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
