This patch introduces FITRIM in f2fs_ioctl.
In this case, f2fs will issue small discards and prefree discards as many as
possible for the given area.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch add a new data structure to control checkpoint parameters.
Currently, it presents the reason of checkpoint such as is_umount and normal
sync.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously, f2fs activates SSR if the # of free segments reaches to the # of
overprovisioned segments.
In this case, SSR starts to use dirty segments only, so that the overprovisoned
space cannot be selected for new data.
This means that we have no chance to utilizae the overprovisioned space at all.
This patch fixes that by allowing LFS allocations until the # of free segments
reaches to the last threshold, reserved space.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch changes the ipu_policy setting to use any combination of orthogonal policies.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In ->get_victim we get max_search value from dirty_i->nr_dirty without
protection of seglist_lock, after that, nr_dirty can be increased/decreased
before we hold seglist_lock lock.
Then in main loop we attempt to traverse all dirty section one time to find
victim section, but it's not accurate to use max_search as the total loop count,
because we might lose checking several sections or check sections redundantly
for the case of nr_dirty are increased or decreased previously.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In manual of mount, we descript remount as below:
"mount -o remount,rw /dev/foo /dir
After this call all old mount options are replaced and arbitrary stuff from
fstab is ignored, except the loop= option which is internally generated and
maintained by the mount command."
Previously f2fs do not clear up old mount options when remount_fs, so we have no
chance of disabling previous option (e.g. flush_merge). Fix it.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Now punching hole in directory is not supported in f2fs, so let's limit file
type in punch_hole().
In addition, in punch_hole if offset is exceed file size, we should skip
punching hole.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Block size in f2fs is 4096 bytes, so theoretically, f2fs can support 4096 bytes
sector device at maximum. But now f2fs only support 512 bytes size sector, so
block device such as zRAM which uses page cache as its block storage space will
not be mounted successfully as mismatch between sector size of zRAM and sector
size of f2fs supported.
In this patch we support large sector size in f2fs, so block device with sector
size of 512/1024/2048/4096 bytes can be supported in f2fs.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
By using FALLOC_FL_KEEP_SIZE in ->fallocate of f2fs, we can fallocate block past
EOF without changing i_size of inode. These blocks past EOF will not be
truncated in ->setattr as we truncate them only when change the file size.
We should give a chance to truncate blocks out of filesize in setattr().
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The f2fs_direct_IO uses __allocate_data_block, but inside the allocation path,
we should update i_size at the changed time to update its inode page.
Otherwise, we can get wrong i_size after roll-forward recovery.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If same data is updated multiple times, we don't need to redo whole the
operations.
Let's just update the lastest one.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In f2fs_sync_file, if there is no written appended writes, it skips
to write its node blocks.
But, if there is up-to-date inode page, we should write it to update
its metadata during the roll-forward recovery.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We can summarize the roll forward recovery scenarios as follows.
[Term] F: fsync_mark, D: dentry_mark
1. inode(x) | CP | inode(x) | dnode(F)
-> Update the latest inode(x).
2. inode(x) | CP | inode(F) | dnode(F)
-> No problem.
3. inode(x) | CP | dnode(F) | inode(x)
-> Recover to the latest dnode(F), and drop the last inode(x)
4. inode(x) | CP | dnode(F) | inode(F)
-> No problem.
5. CP | inode(x) | dnode(F)
-> The inode(DF) was missing. Should drop this dnode(F).
6. CP | inode(DF) | dnode(F)
-> No problem.
7. CP | dnode(F) | inode(DF)
-> If f2fs_iget fails, then goto next to find inode(DF).
8. CP | dnode(F) | inode(x)
-> If f2fs_iget fails, then goto next to find inode(DF).
But it will fail due to no inode(DF).
So, this patch adds some missing points such as #1, #5, #7, and #8.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch revisited whole the recovery information during the f2fs_sync_file.
In this patch, there are three information to make a decision.
a) IS_CHECKPOINTED, /* is it checkpointed before? */
b) HAS_FSYNCED_INODE, /* is the inode fsynced before? */
c) HAS_LAST_FSYNC, /* has the latest node fsync mark? */
And, the scenarios for our rule are based on:
[Term] F: fsync_mark, D: dentry_mark
1. inode(x) | CP | inode(x) | dnode(F)
2. inode(x) | CP | inode(F) | dnode(F)
3. inode(x) | CP | dnode(F) | inode(x) | inode(F)
4. inode(x) | CP | dnode(F) | inode(F)
5. CP | inode(x) | dnode(F) | inode(DF)
6. CP | inode(DF) | dnode(F)
7. CP | dnode(F) | inode(DF)
8. CP | dnode(F) | inode(x) | inode(DF)
For example, #3, the three conditions should be changed as follows.
inode(x) | CP | dnode(F) | inode(x) | inode(F)
a) x o o o o
b) x x x x o
c) x o o x o
If f2fs_sync_file stops ------^,
it should write inode(F) --------------^
So, the need_inode_block_update should return true, since
c) get_nat_flag(e, HAS_LAST_FSYNC), is false.
For example, #8,
CP | alloc | dnode(F) | inode(x) | inode(DF)
a) o x x x x
b) x x x o
c) o o x o
If f2fs_sync_file stops -------^,
it should write inode(DF) --------------^
Note that, the roll-forward policy should follow this rule, which means,
if there are any missing blocks, we doesn't need to recover that inode.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a flag in the nat entry structure to merge various
information such as checkpointed and fsync_done marks.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously, all the dnode pages should be read during the roll-forward recovery.
Even worsely, whole the chain was traversed twice.
This patch removes that redundant and costly read operations by using page cache
of meta_inode and readahead function as well.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If the inode is same and its data index are needed to truncate, we can fall into
double lock for its inode page via get_dnode_of_data.
Error case is like this.
1. write data 1, 2, 3, 4, 5 in inode #4.
2. write data 100, 102, 103, 104, 105 in dnode #6 of inode #4.
3. sync
4. update data 100->106 in dnode #6.
5. fsync inode #4.
6. power-cut
-> Then,
1. go back to #3's checkpoint
2. in do_recover_data, get_dnode_of_data() gets inode #4.
3. detect 100->106 in dnode #6.
4. check_index_in_prev_nodes tries to truncate 100 in dnode #6.
5. to trigger truncate_hole, get_dnode_of_data should grab inode #4.
6. detect *kernel hang*
This patch should resolve that bug.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The nm_i->fcnt checking is executed before spin_lock, so if another
thread delete the last free_nid from the list, the wrong nid may be
gotten. So fix the race condition by moving the nm_i->fnct checking
into spin_lock.
Signed-off-by: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Now, if there is no free nid in nm_i->free_nid_list, 0 may be saved
into next_free_nid of checkpoint, this may cause useless scanning for
next mount. nm_i->next_scan_nid should be a better default value than
0.
Signed-off-by: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If user wrote F2FS_IPU_FSYNC:4 in /sys/fs/f2fs/ipu_policy, f2fs_sync_file
only starts to try in-place-updates.
And, if the number of dirty pages is over /sys/fs/f2fs/min_fsync_blocks, it
keeps out-of-order manner. Otherwise, it triggers in-place-updates.
This may be used by storage showing very high random write performance.
For example, it can be used when,
Seq. writes (Data) + wait + Seq. writes (Node)
is pretty much slower than,
Rand. writes (Data)
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously f2fs only counts dirty dentry pages, but there is no reason not to
expand the scope.
This patch changes the names on the management of dirty pages and to count
dirty pages in each inode info as well.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If application throws negative value of lseek with SEEK_DATA|SEEK_HOLE,
previous f2fs went into BUG_ON in get_dnode_of_data, which was reported
by Tommi Rantala.
He could make a simple code to detect this having:
lseek(fd, -17595150933902LL, SEEK_DATA);
This patch should resolve that bug.
Reported-by: Tommi Rentala <tt.rantala@gmail.com>
[Jaegeuk Kim: relocate the condition as suggested by Chao]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In gc_node_segment, if node page gc is run concurrently with node page
writeback, and check_valid_map and get_node_page run after page locked
and before cur_valid_map is updated as below, it is possible for the
page to be written twice unnecessarily.
sync_node_pages
try_lock_page
...
check_valid_map f2fs_write_node_page
...
write_node_page
do_write_page
allocate_data_block
...
refresh_sit_entry /* update cur_valid_map */
...
...
unlock_page
get_node_page
...
set_page_dirty
...
f2fs_put_page
unlock_page
This can be solved via calling check_valid_map after get_node_page again.
Signed-off-by: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We use flush cmd control to collect many flush cmds, and flush them
together. In this case, we use two list to manage the flush cmds
(collect and dispatch), and one spin lock is used to protect this.
In fact, the lock-less list(llist) is very suitable to this case,
and we use simplify this routine.
-
v2:
-use llist_for_each_entry_safe to fix possible use-after-free issue.
-remove the unused field from struct flush_cmd.
Thanks for Yu's suggestion.
-
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In commit aec71382c6 ("f2fs: refactor flush_nat_entries codes for reducing NAT
writes"), we descripte the issue as below:
"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."
Actually, we have the same problem in using SIT journal area.
In this patch, firstly we will update sit journal with dirty entries as many as
possible. Secondly if there is no space in sit journal, we will remove all
entries in journal and walk through the whole dirty entry bitmap of sit,
accounting dirty sit entries located in same SIT block to sit entry set. All
entry sets are linked to list sit_entry_set in sm_info, sorted ascending order
by count of entries in set. Later we flush entries in set which have fewest
entries into journal as many as we can, and then flush dense set with merged
entries to disk.
In this way we can use sit journal area more effectively, also we will reduce
SIT update, result in gaining in performance and saving lifetime of flash
device.
In my testing environment, it shows this patch can help to reduce SIT block
update obviously.
virtual machine + hard disk:
fsstress -p 20 -n 400 -l 5
sit page num cp count sit pages/cp
based 2006.50 1349.75 1.486
patched 1566.25 1463.25 1.070
Our latency of merging op is small when handling a great number of dirty SIT
entries in flush_sit_entries:
latency(ns) dirty sit count
36038 2151
49168 2123
37174 2232
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
sit_i in macro SIT_BLOCK_OFFSET/START_SEGNO is not used, remove it.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch replaces BUG cases with f2fs_bug_on to remain fsck.f2fs information.
And it implements some void functions to initiate fsck.f2fs too.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Pull f2fs bug fixes from Jaegeuk Kim:
"This series includes patches to:
- fix recovery routines
- fix bugs related to inline_data/xattr
- fix when casting the dentry names
- handle EIO or ENOMEM correctly
- fix memory leak
- fix lock coverage"
* tag 'for-f2fs-3.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (28 commits)
f2fs: reposition unlock_new_inode to prevent accessing invalid inode
f2fs: fix wrong casting for dentry name
f2fs: simplify by using a literal
f2fs: truncate stale block for inline_data
f2fs: use macro for code readability
f2fs: introduce need_do_checkpoint for readability
f2fs: fix incorrect calculation with total/free inode num
f2fs: remove rename and use rename2
f2fs: skip if inline_data was converted already
f2fs: remove rewrite_node_page
f2fs: avoid double lock in truncate_blocks
f2fs: prevent checkpoint during roll-forward
f2fs: add WARN_ON in f2fs_bug_on
f2fs: handle EIO not to break fs consistency
f2fs: check s_dirty under cp_mutex
f2fs: unlock_page when node page is redirtied out
f2fs: introduce f2fs_cp_error for readability
f2fs: give a chance to mount again when encountering errors
f2fs: trigger release_dirty_inode in f2fs_put_super
f2fs: don't skip checkpoint if there is no dirty node pages
...
Pull key subsystem fixes from James Morris:
"Fixes for the keys subsystem, one of which addresses a use-after-free
bug"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
PEFILE: Relax the check on the length of the PKCS#7 cert
KEYS: Fix use-after-free in assoc_array_gc()
KEYS: Fix public_key asymmetric key subtype name
KEYS: Increase root_maxkeys and root_maxbytes sizes
Another handful of arm64 fixes here:
- A few fixes for real issues found by smatch (after Dan's talk at KS)
- Revert the /proc/cpuinfo changes merged during the merge window.
We've opened a can of worms here, so we need to find out where we
stand before we change this interface.
- Implement KSTK_ESP for compat tasks, otherwise 32-bit Android gets
confused wondering where its [stack] has gone
- Misc fixes (fpsimd context handling, crypto, ...)
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull more arm64 fixes from Will Deacon:
"Another handful of arm64 fixes here. They address some issues found
by running smatch on the arch code (ignoring the false positives) and
also stop 32-bit Android from losing track of its stack.
There's one additional irq migration fix in the pipeline, but it came
in after I'd tagged and tested this set.
- a few fixes for real issues found by smatch (after Dan's talk at KS)
- revert the /proc/cpuinfo changes merged during the merge window.
We've opened a can of worms here, so we need to find out where we
stand before we change this interface.
- implement KSTK_ESP for compat tasks, otherwise 32-bit Android gets
confused wondering where its [stack] has gone
- misc fixes (fpsimd context handling, crypto, ...)"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
Revert "arm64: cpuinfo: print info for all CPUs"
arm64: fix bug for reloading FPSIMD state after cpu power off
arm64: report correct stack pointer in KSTK_ESP for compat tasks
arm64: Add brackets around user_stack_pointer()
arm64: perf: don't rely on layout of pt_regs when grabbing sp or pc
arm64: ptrace: fix compat reg getter/setter return values
arm64: ptrace: fix compat hardware watchpoint reporting
arm64: Remove unused variable in head.S
arm64/crypto: remove redundant update of data
Pull LED fix from Bryan Wu:
"Hugh, Jiri and many other people found a kernel oops due to a LED
change merged recently. Now the right fix might just revert it and
avoid the kernel oops"
* 'leds-fixes-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
Revert "leds: convert blink timer to workqueue"
Relax the check on the length of the PKCS#7 cert as it appears that the PE
file wrapper size gets rounded up to the nearest 8.
The debugging output looks like this:
PEFILE: ==> verify_pefile_signature()
PEFILE: ==> pefile_parse_binary()
PEFILE: checksum @ 110
PEFILE: header size = 200
PEFILE: cert = 968 @547be0 [68 09 00 00 00 02 02 00 30 82 09 56 ]
PEFILE: sig wrapper = { 968, 200, 2 }
PEFILE: Signature data not PKCS#7
The wrapper is the first 8 bytes of the hex dump inside []. This indicates a
length of 0x968 bytes, including the wrapper header - so 0x960 bytes of
payload.
The ASN.1 wrapper begins [ ... 30 82 09 56 ]. That indicates an object of size
0x956 - a four byte discrepency, presumably just padding for alignment
purposes.
So we just check that the ASN.1 container is no bigger than the payload and
reduce the recorded size appropriately.
Whilst we're at it, allow shorter PKCS#7 objects that manage to squeeze within
127 or 255 bytes. It's just about conceivable if no X.509 certs are included
in the PKCS#7 message.
Reported-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Peter Jones <pjones@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
An edit script should be considered inaccessible by a function once it has
called assoc_array_apply_edit() or assoc_array_cancel_edit().
However, assoc_array_gc() is accessing the edit script just after the
gc_complete: label.
Reported-by: Andreea-Cristina Bernat <bernat.ada@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Andreea-Cristina Bernat <bernat.ada@gmail.com>
cc: shemming@brocade.com
cc: paulmck@linux.vnet.ibm.com
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
The length of the name of an asymmetric key subtype must be stored in struct
asymmetric_key_subtype::name_len so that it can be matched by a search for
"<subkey_name>:<partial_fingerprint>". Fix the public_key subtype to have
name_len set.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Now that NFS client uses the kernel key ring facility to store the NFSv4
id/gid mappings, the defaults for root_maxkeys and root_maxbytes need to be
substantially increased.
These values have been soak tested:
https://bugzilla.redhat.com/show_bug.cgi?id=1033708#c73
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
As the race condition on the inode cache, following scenario can appear:
[Thread a] [Thread b]
->f2fs_mkdir
->f2fs_add_link
->__f2fs_add_link
->init_inode_metadata failed here
->gc_thread_func
->f2fs_gc
->do_garbage_collect
->gc_data_segment
->f2fs_iget
->iget_locked
->wait_on_inode
->unlock_new_inode
->move_data_page
->make_bad_inode
->iput
When we fail in create/symlink/mkdir/mknod/tmpfile, the new allocated inode
should be set as bad to avoid being accessed by other thread. But in above
scenario, it allows f2fs to access the invalid inode before this inode was set
as bad.
This patch fix the potential problem, and this issue was found by code review.
change log from v1:
o Add condition judgment in gc_data_segment() suggested by Changman Lee.
o use iget_failed to simplify code.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Pull irq handling fixlet from Thomas Gleixner:
"Just an export for an interrupt flow handler which is now used in gpio
modules"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irq: Export handle_fasteoi_irq
It turns out that vendors are relying on the format of /proc/cpuinfo,
and we've even spotted out-of-tree hacks attempting to make it look
identical to the format used by arch/arm/. That means we can't afford to
churn this interface in mainline, so revert the recent reformatting of
the file for arm64 pending discussions on the list to find out what
people actually want.
This reverts commit d7a49086f2.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Now arm64 defers reloading FPSIMD state, but this optimization also
introduces the bug after cpu resume back from low power mode.
The reason is after the cpu has been powered off, s/w need set the
cpu's fpsimd_last_state to NULL so that it will force to reload
FPSIMD state for the thread, otherwise there has the chance to meet
the condition for both the task's fpsimd_state.cpu field contains the
id of the current cpu, and the cpu's fpsimd_last_state per-cpu variable
points to the task's fpsimd_state, so finally kernel will skip to reload
the context during it return back to userland.
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Leo Yan <leoy@marvell.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Jaegeuk Kim
Chao Yu
Huang Ying
Gu Zheng
Linus Torvalds
Noam Camus
David Howells
Steve Dickson
Jiri Kosina
Will Deacon
Leo Yan