We do not need to block on ->node_write among different node page writers e.g.
fsync/flush, unless we have a node page writer from write_checkpoint.
So it's better use rw_semaphore instead of mutex type for ->node_write to
promote performance.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
There are redundant lines in allocate_data_block.
In this function, we call refresh_sit_entry with old seg and old curseg.
After that, we call locate_dirty_segment with old curseg.
But, the new address is always allocated from old curseg and
we call locate_dirty_segment with old curseg in refresh_sit_entry.
So, we do not need to call locate_dirty_segment with old curseg again.
We've discussed like below:
Jaegeuk said:
"When considering SSR, we need to take care of the following scenario.
- old segno : X
- new address : Z
- old curseg : Y
This means, a new block is supposed to be written to Z from X.
And Z is newly allocated in the same path from Y.
In that case, we should trigger locate_dirty_segment for Y, since
it was a current_segment and can be dirty owing to SSR.
But that was not included in the dirty list."
Changman said:
"We already choosed old curseg(Y) and then we allocate new address(Z) from old
curseg(Y). After that we call refresh_sit_entry(old address, new address).
In the funcation, we call locate_dirty_segment with old seg and old curseg.
So calling locate_dirty_segment after refresh_sit_entry again is redundant."
Jaegeuk said:
"Right. The new address is always allocated from old_curseg."
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Dongho Sim <dh.sim@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If the bit is already set, we don't need to reset it, and vice versa.
Because we don't need to make the caches dirty for that.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch enforces in-place-updates only when fdatasync is requested.
If we adopt this in-place-updates for the fdatasync, we can skip to write the
recovery information.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch intends to improve the fsync performance by skipping remaining the
recovery information, only when there is no data that we should recover.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a inode number list in which represents inodes having
appended data writes or updated data writes after last checkpoint.
This will be used at fsync to determine whether the recovery information
should be written or not.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
For better ino management, this patch replaces the data structure from list
to radix tree.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch changes the naming of orphan-related data structures to use as
inode numbers managed globally.
Later, we can use this facility for managing any inode number lists.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch punches out the core functions to manage the inode numbers.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds a mount option, nobarrier, in f2fs.
The assumption in here is that file system keeps the IO ordering, but
doesn't care about cache flushes inside the storages.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We should put root inode correctly in error path of fill_super, otherwise we
may encounter a leak case of inode resource.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Now new interface ->rename2() is added to VFS, here are related description:
https://lkml.org/lkml/2014/2/7/873https://lkml.org/lkml/2014/2/7/758
This patch adds function f2fs_rename2() to support ->rename2() including
handling both RENAME_EXCHANGE and RENAME_NOREPLACE flag.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Otherwise, if a large amount of direct IO writes were done, the
segment allocation may be failed because no enough segments are gced.
Changes:
v2: add f2fs_balance_fs into __get_data_block instead of f2fs_direct_IO.
Signed-off-by: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In __set_test_and_free we will check whether all segment are free in one section
When free one segment, in order to set section to free status.
But the searching region of segmap is from start segno to last segno of f2fs,
it's not necessary. So let's just only check all segment bitmap of target
section.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We assume that modification of some special application could result in zeroed
name_len, or it is consciously made by somebody. We will deadloop in
find_in_block when name_len of dir entry is zero.
This patch is added for preventing deadloop in above scenario.
change log from v1:
o use f2fs_bug_on rather than break out from searching dir entry suggested by
Jaegeuk Kim.
Jaegeuk describe:
"Well, IMO, it would be good to add f2fs_bug_on() here with a specific comment.
In the current phase of f2fs, it is more important to investigate the file
system bugs, rather than workarounds for any corrupted images.
And, definitely it needs to stop the kernel if any corrupted image was mounted,
so that we can figure out where the bugs are occurred."
Suggested-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this patch we use below inner macro and function to clean up codes.
1. ADDRS_PER_PAGE
2. SM_I
3. f2fs_readonly
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When we fail in ->write_begin()/->direct_IO(), our allocated node block in disk
and page cache are still kept, despite these may not be used again.
This patch introduce f2fs_write_failed() to handle the error case of these two
interfaces, it will truncate page cache and blocks of this file according to
i_size.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
kernel side(xx_init_acl), the acl is get/cloned from the parent dir's,
which is credible. So remove the redundant validation check of acl
here.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In our rename process, region of f2fs_lock_op covered is too big as some of the
code like f2fs_empty_dir/f2fs_find_entry are not needed to protect by this lock.
So in the extreme case like doing checkpoint when we rename old inode to exist
inode in a large directory could cause lower concurrency.
Let's reduce the region of f2fs_lock_op to fix this.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Although building NAT journal in cursum reduce the read/write work for NAT
block, but previous design leave us lower performance when write checkpoint
frequently for these cases:
1. if journal in cursum has already full, it's a bit of waste that we flush all
nat entries to page for persistence, but not to cache any entries.
2. if journal in cursum is not full, we fill nat entries to journal util
journal is full, then flush the left dirty entries to disk without merge
journaled entries, so these journaled entries may be flushed to disk at next
checkpoint but lost chance to flushed last time.
In this patch we merge dirty entries located in same NAT block to nat entry set,
and linked all set to list, sorted ascending order by entries' count of set.
Later we flush entries in sparse set into journal as many as we can, and then
flush merged entries to disk. In this way we can not only gain in performance,
but also save lifetime of flash device.
In my testing environment, it shows this patch can help to reduce NAT block
writes obviously. In hard disk test case: cost time of fsstress is stablely
reduced by about 5%.
1. virtual machine + hard disk:
fsstress -p 20 -n 200 -l 5
node num cp count nodes/cp
based 4599.6 1803.0 2.551
patched 2714.6 1829.6 1.483
2. virtual machine + 32g micro SD card:
fsstress -p 20 -n 200 -l 1 -w -f chown=0 -f creat=4 -f dwrite=0
-f fdatasync=4 -f fsync=4 -f link=0 -f mkdir=4 -f mknod=4 -f rename=5
-f rmdir=5 -f symlink=0 -f truncate=4 -f unlink=5 -f write=0 -S
node num cp count nodes/cp
based 84.5 43.7 1.933
patched 49.2 40.0 1.23
Our latency of merging op shows not bad when handling extreme case like:
merging a great number of dirty nats:
latency(ns) dirty nat count
3089219 24922
5129423 27422
4000250 24523
change log from v1:
o fix wrong logic in add_nat_entry when grab a new nat entry set.
o swith to create slab cache in create_node_manager_caches.
o use GFP_ATOMIC instead of GFP_NOFS to avoid potential long latency.
change log from v2:
o make comment position more appropriate suggested by Jaegeuk Kim.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds f2fs_do_tmpfile to eliminate the redundant init_inode_metadata
flow.
Throught this, we can provide the consistent lock usage, e.g., fi->i_sem, and
this will enable better debugging stuffs.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Add function f2fs_tmpfile() to support O_TMPFILE file creation, and modify logic
of init_inode_metadata to enable linkat temp file.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
After we call find_data_page in truncate_partial_data_page, we could not
guarantee this page is updated or not as error may occurred in lower layer.
We'd better check status of the page to avoid this no updated page be
writebacked to device.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We have already set page update in ->write_begin, so we should remove redundant
SetPageUptodate in ->write_end.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
o fix normal and recovery path for fallocated regions
o fix error case mishandling
o recover renamed fsync inodes correctly
o fix to get out of infinite loops in balance_dirty_pages
o fix kernel NULL pointer error
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Merge tag 'f2fs-fixes-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs bugfixes from Jaegeuk Kim:
"This includes a couple of bug fixes found by xfstests. In addition,
one critical bug was reported by Brian Chadwick, which is falling into
the infinite loop in balance_dirty_pages. And it turned out due to
the IO merging policy in f2fs, which was newly merged in 3.16.
- fix normal and recovery path for fallocated regions
- fix error case mishandling
- recover renamed fsync inodes correctly
- fix to get out of infinite loops in balance_dirty_pages
- fix kernel NULL pointer error"
* tag 'f2fs-fixes-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
f2fs: avoid to access NULL pointer in issue_flush_thread
f2fs: check bdi->dirty_exceeded when trying to skip data writes
f2fs: do checkpoint for the renamed inode
f2fs: release new entry page correctly in error path of f2fs_rename
f2fs: fix error path in init_inode_metadata
f2fs: check lower bound nid value in check_nid_range
f2fs: remove unused variables in f2fs_sm_info
f2fs: fix not to allocate unnecessary blocks during fallocate
f2fs: recover fallocated data and its i_size together
f2fs: fix to report newly allocate region as extent
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=75861
Denis 2014-05-10 11:28:59 UTC reported:
"F2FS-fs (mmcblk0p28): mounting..
Unable to handle kernel NULL pointer dereference at virtual address 00000018
...
[<c0a2f678>] (_raw_spin_lock+0x3c/0x70) from [<c03a0330>] (issue_flush_thread+0x50/0x17c)
[<c03a0330>] (issue_flush_thread+0x50/0x17c) from [<c01b4064>] (kthread+0x98/0xa4)
[<c01b4064>] (kthread+0x98/0xa4) from [<c0108060>] (kernel_thread_exit+0x0/0x8)"
This patch assign cmd_control_info in sm_info before issue_flush_thread is being
created, so this make sure that issue flush thread will have no chance to access
invalid info in fcc.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If we don't check the current backing device status, balance_dirty_pages can
fall into infinite pausing routine.
This can be occurred when a lot of directories make a small number of dirty
dentry pages including files.
Reported-by: Brian Chadwick <brianchad@westnet.com.au>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If an inode is renamed, it should be registered as file_lost_pino to conduct
checkpoint at f2fs_sync_file.
Otherwise, the inode cannot be recovered due to no dent_mark in the following
scenario.
Note that, this scenario is from xfstests/322.
1. create "a"
2. fsync "a"
3. rename "a" to "b"
4. fsync "b"
5. Sudden power-cut
After recovery is done, "b" should be seen.
However, the result shows "a", since the recovery procedure does not enter
recover_dentry due to no dent_mark.
The reason is like below.
- The nid of "a" is checkpointed during #2, f2fs_sync_file.
- The inode page for "b" produced by #3 is written without dent_mark by
sync_node_pages.
So, this patch fixes this bug by assinging file_lost_pino to the "a"'s inode.
If the pino is lost, f2fs_sync_file conducts checkpoint, and then recovers
the latest pino and its dentry information for further recovery.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch correct releasing code of new_page to avoid BUG_ON in error patch of
f2fs_rename.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If we fail in this path:
->init_inode_metadata
->make_empty_dir
->get_new_data_page
->grab_cache_page return -ENOMEM
We will bug on in error path of init_inode_metadata when call remove_inode_page
because i_block = 2 (one inode block will be released later & one dentry block).
We should release the dentry block in init_inode_metadata to avoid this BUG_ON,
and avoid leak of dentry block resource, because we never have second chance to
release that block in ->evict_inode as in upper error path we make this inode
'bad'.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch add lower bound verification for nid in check_nid_range, so nids
reserved like 0, node, meta passed by caller could be checked there.
And then check_nid_range could be used in f2fs_nfs_get_inode for simplifying
code.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Nothing major, but potentially annoying and worthwhile to fix.
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Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon fixes from Guenter Roeck:
"Fix a number of zero-day bugs, mostly found with module test scripts.
Nothing major, but potentially annoying and worthwhile to fix"
* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (adc128d818) Drop write support on inX_input attributes
hwmon: (emc2103) Clamp limits instead of bailing out
hwmon: (adm1031) Fix writes to limit registers
hwmon: (adm1021) Fix cache problem when writing temperature limits
hwmon: (adm1029) Ensure the fan_div cache is updated in set_fan_div
hwmon: (amc6821) Fix permissions for temp2_input
hwmon: (ntc_thermistor) Correct information printed during probe
Pull thermal fixes from Zhang Rui:
"Specifics:
- update Email address of Thermal subsystem maintainer Eduardo
Valentin.
- fix a problem that unloading thermal module results in kernel crash
because a non-exist device file is removed on thermal unload.
- fix a problem that critical trip point is set wrongly on latest
i.MX6 SOC and results in system critical shutdown.
- a couple of fixes to Tmon tool, of-thermal code and ti thermal
driver"
* 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
tmon: set umask to a reasonable value
tmon: Check log file for common secuirty issues
tools/thermal: tmon: fix compilation errors when building statically
thermal: ti-soc-thermal: ti-bandgap.c: Cleaning up wrong address is checked
Thermal: imx: correct critical trip temperature setting
thermal: Bind cooling devices with the correct arguments
thermal: Add braces around suspect code
thermal: hwmon: Make the check for critical temp valid consistent
MAINTAINERS: Update Eduardo Valentin's email address
Pull HID fixes from Jiri Kosina:
"A few tiny HID subsystem fixes for 3.16"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
HID: use multi input quirk for 22b9:2968
HID: sensor-hub: fix potential memory leak
HID: usbhid: quirk for PM1610 and PM1640 Touchscreen.
HID: rmi: Protect PM-only functions by #ifdef CONFIG_PM
HID: sensor-hub: introduce Kconfig dependency on IOMEM
HID: sensor-hub: make dyn_callback_lock IRQ-safe
the errorpath in probe().
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Merge tag 'pinctrl-v3.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control fixes from Linus Walleij:
"Two fixes for the pin control subsystem, both relating to the error
path in probe()
I'm a bit snowed under by mail but these have boiled in linux-next and
should propagate to you"
* tag 'pinctrl-v3.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: berlin: fix an error code in berlin_pinctrl_probe()
pinctrl: sunxi: Fix potential null pointer dereference
Writes into input registers doesn't make sense, even more so since
the writes actually ended up writing into the maximum limit registers.
Drop it.
Cc: stable@vger.kernel.org
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
It is customary to clamp limits instead of bailing out with an error
if a configured limit is out of the range supported by the driver.
This simplifies limit configuration, since the user will not typically
know chip and/or driver specific limits.
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
