The inode_page_locked should be a boolean variable.
struct dnode_of_data {
struct inode *inode; /* vfs inode pointer */
struct page *inode_page; /* its inode page, NULL is possible */
struct page *node_page; /* cached direct node page */
nid_t nid; /* node id of the direct node block */
unsigned int ofs_in_node; /* data offset in the node page */
==> bool inode_page_locked; /* inode page is locked or not */
block_t data_blkaddr; /* block address of the node block */
};
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: add description]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Let's send REQ_META or REQ_PRIO when reading meta area such as NAT/SIT
etc.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Change log from v1:
o add mark_page_accessed() not to reclaim the nat pages.
This patch changes the policy of submitting read bios at ra_nat_pages.
Previously, f2fs submits small read bios with block plugging.
But, with this patch, f2fs itself merges read bios first and then submits a
large bio, which can reduce the bio handling overheads.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In wait_on_node_pages_writeback we will test and clear error flag for all
pages in radix tree, but not necessary.
So we only do this for pages belong to the specified inode.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously, f2fs_sync_file() waits for all the node blocks to be written.
But, we don't need to do that, but wait only the inode-related node blocks.
This patch adds wait_on_node_pages_writeback() in which waits inode-related
node blocks that are on writeback.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If you want to remove unnecessary BUG_ONs, you can just turn off F2FS_CHECK_FS
in your kernel config.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch merges some background jobs into this new function.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously, f2fs postpones reclaiming prefree segments into free segments
as much as possible.
However, if user writes and deletes a bunch of data without any sync or fsync
calls, some flash storages can suffer from garbage collections.
So, this patch adds the reclaiming codes to f2fs_write_node_pages and background
GC thread.
If there are a lot of prefree segments, let's do checkpoint so that f2fs
submits discard commands for the prefree regions to the flash storage.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Introduce the unfailed version of kmem_cache_alloc named f2fs_kmem_cache_alloc
to hide the retry routine and make the code a bit cleaner.
v2:
Fix the wrong use of 'retry' tag pointed out by Gao feng.
Use more neat code to remove redundant tag suggested by Haicheng Li.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch enhances the recovery routine not to write any data/node/meta until
its completion.
If any writes are sent to the disk, it could contaminate the written history
that will be used for further recovery.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously, we experience bio traces as follows when running simple sequential
write test.
f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500104928, size = 4K
f2fs_do_submit_bio: type = NODE, io = no sync, sector = 499922208, size = 368K
f2fs_do_submit_bio: type = NODE, io = no sync, sector = 499914752, size = 140K
-> total 512K
The first one is to write an indirect node block, and the others are to write
direct node blocks.
The reason why there are two separate bios for direct node blocks is:
0. initial state
------------------ ------------------
| | |xxxxxxxx |
------------------ ------------------
1. write 368K
------------------ ------------------
| | |xxxxxxxxWWWWWWWW|
------------------ ------------------
2. write 140K
------------------ ------------------
|WWWWWWW | |xxxxxxxxWWWWWWWW|
------------------ ------------------
This is because f2fs_write_node_pages tries to write just 512K totally, so that
we can lose the chance to merge more bios nicely.
After this patch is applied, we can get the following bio traces.
f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500103168, size = 8K
f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500111368, size = 4K
f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500107272, size = 512K
f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500108296, size = 512K
f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500109320, size = 500K
And finally, we can improve the sequential write performance,
from 458.775 MB/s to 479.945 MB/s on SSD.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
0. modified inode structure
--------------------------------------
metadata (e.g., i_mtime, i_ctime, etc)
--------------------------------------
direct pointers [0 ~ 873]
inline xattrs (200 bytes by default)
indirect pointers [0 ~ 4]
--------------------------------------
node footer
--------------------------------------
1. setxattr flow
- read_all_xattrs copies all the xattrs from inline and xattr node block.
- handle xattr entries
- write_all_xattrs copies modified xattrs into inline and xattr node block.
2. getxattr flow
- read_all_xattrs copies all the xattrs from inline and xattr node block.
- check target entries
3. Usage
# mount -t f2fs -o inline_xattr $DEV $MNT
Once mounted with the inline_xattr option, f2fs marks all the newly created
files to reserve an amount of inline xattr space explicitly inside the inode
block. Without the mount option, f2fs will not touch any existing files and
newly created files as well.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch enables the number of direct pointers inside on-disk inode block to
be changed dynamically according to the size of inline xattr space.
The number of direct pointers, ADDRS_PER_INODE, can be changed only if the file
has inline xattr flag.
The number of direct pointers that will be used by inline xattrs is defined as
F2FS_INLINE_XATTR_ADDRS.
Current patch assigns F2FS_INLINE_XATTR_ADDRS to 0 temporarily.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
alloc_page() returns a NULL on failure, it never returns an ERR_PTR.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously, f2fs_setxattr assigns i_xattr_nid in the inode page inconsistently.
The scenario is:
= Thread 1 = = Thread 2 = = fi->i_xattr_nid = = on-disk nid =
f2fs_setxattr 0 0
new_node_page X 0
sync_inode_page X X
checkpoint X X -.
grab_cache_page X X |
--> allocate a new xattr node block or -ENOSPC <----------------'
At this moment, the checkpoint stores inconsistent data where the inode has
i_xattr_nid but actual xattr node block is not allocated yet.
So, we should assign the real i_xattr_nid only after its xattr node block is
allocated.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Introduce help function F2FS_NODE() to simplify the conversion of node_page to
f2fs_node.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
o remount_fs callback function
o restore parent inode number to enhance the fsync performance
o xattr security labels
o reduce the number of redundant lock/unlock data pages
o avoid frequent write_inode calls
The other minor bug fixes are as follows.
o endian conversion bugs
o various bugs in the roll-forward recovery routine
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Merge tag 'for-f2fs-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"This patch-set includes the following major enhancement patches:
- remount_fs callback function
- restore parent inode number to enhance the fsync performance
- xattr security labels
- reduce the number of redundant lock/unlock data pages
- avoid frequent write_inode calls
The other minor bug fixes are as follows.
- endian conversion bugs
- various bugs in the roll-forward recovery routine"
* tag 'for-f2fs-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (56 commits)
f2fs: fix to recover i_size from roll-forward
f2fs: remove the unused argument "sbi" of func destroy_fsync_dnodes()
f2fs: remove reusing any prefree segments
f2fs: code cleanup and simplify in func {find/add}_gc_inode
f2fs: optimize the init_dirty_segmap function
f2fs: fix an endian conversion bug detected by sparse
f2fs: fix crc endian conversion
f2fs: add remount_fs callback support
f2fs: recover wrong pino after checkpoint during fsync
f2fs: optimize do_write_data_page()
f2fs: make locate_dirty_segment() as static
f2fs: remove unnecessary parameter "offset" from __add_sum_entry()
f2fs: avoid freqeunt write_inode calls
f2fs: optimise the truncate_data_blocks_range() range
f2fs: use the F2FS specific flags in f2fs_ioctl()
f2fs: sync dir->i_size with its block allocation
f2fs: fix i_blocks translation on various types of files
f2fs: set sb->s_fs_info before calling parse_options()
f2fs: support xattr security labels
f2fs: fix iget/iput of dir during recovery
...
This patch adds the support of security labels for f2fs, which will be used
by Linus Security Models (LSMs).
Quote from http://en.wikipedia.org/wiki/Linux_Security_Modules:
"Linux Security Modules (LSM) is a framework that allows the Linux kernel to
support a variety of computer security models while avoiding favoritism toward
any single security implementation. The framework is licensed under the terms of
the GNU General Public License and is standard part of the Linux kernel since
Linux 2.6. AppArmor, SELinux, Smack and TOMOYO Linux are the currently accepted
modules in the official kernel.".
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
I found a bug when testing power-off-recovery as follows.
[Bug Scenario]
1. create a file
2. fsync the file
3. reboot w/o any sync
4. try to recover the file
- found its fsync mark
- found its dentry mark
: try to recover its dentry
- get its file name
- get its parent inode number
: here we got zero value
The reason why we get the wrong parent inode number is that we didn't
synchronize the inode page with its newly created inode information perfectly.
Especially, previous f2fs stores fi->i_pino and writes it to the cached
node page in a wrong order, which incurs the zero-valued i_pino during the
recovery.
So, this patch modifies the creation flow to fix the synchronization order of
inode page with its inode.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If get_dnode_of_data gets a locked node page, let's skip redundant
get_node_page calls.
This is for the futher enhancement.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Currently f2fs recovers the dentry of fsynced files.
When power-off-recovery is conducted, this newly recovered inode should increase
node block count as well as inode block count.
This patch resolves this inconsistency that results in:
1. create a file
2. write data
3. fsync
4. reboot without sync
5. mount and recover the file
6. node block count is 1 and inode block count is 2
: fall into the inconsistent state
7. unlink the file
: trigger the following BUG_ON
------------[ cut here ]------------
kernel BUG at /home/zeus/f2fs_test/src/fs/f2fs/f2fs.h:716!
Call Trace:
[<ffffffffa0344100>] ? get_node_page+0x50/0x1a0 [f2fs]
[<ffffffffa0344bfc>] remove_inode_page+0x8c/0x100 [f2fs]
[<ffffffffa03380f0>] ? f2fs_evict_inode+0x180/0x2d0 [f2fs]
[<ffffffffa033812e>] f2fs_evict_inode+0x1be/0x2d0 [f2fs]
[<ffffffff811c7a67>] evict+0xa7/0x1a0
[<ffffffff811c82b5>] iput+0x105/0x190
[<ffffffff811c2b30>] d_kill+0xe0/0x120
[<ffffffff811c2c57>] dput+0xe7/0x1e0
[<ffffffff811acc3d>] __fput+0x19d/0x2d0
[<ffffffff811acd7e>] ____fput+0xe/0x10
[<ffffffff81070645>] task_work_run+0xb5/0xe0
[<ffffffff81002941>] do_notify_resume+0x71/0xb0
[<ffffffff8175f14a>] int_signal+0x12/0x17
Reported-and-Tested-by: Chris Fries <C.Fries@motorola.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Currently there is no way to truncate partial page where the end
truncate point is not at the end of the page. This is because it was not
needed and the functionality was enough for file system truncate
operation to work properly. However more file systems now support punch
hole feature and it can benefit from mm supporting truncating page just
up to the certain point.
Specifically, with this functionality truncate_inode_pages_range() can
be changed so it supports truncating partial page at the end of the
range (currently it will BUG_ON() if 'end' is not at the end of the
page).
This commit changes the invalidatepage() address space operation
prototype to accept range to be invalidated and update all the instances
for it.
We also change the block_invalidatepage() in the same way and actually
make a use of the new length argument implementing range invalidation.
Actual file system implementations will follow except the file systems
where the changes are really simple and should not change the behaviour
in any way .Implementation for truncate_page_range() which will be able
to accept page unaligned ranges will follow as well.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
After build_free_nids() searches free nid candidates from nat pages and
current journal blocks, it checks all the candidates if they are allocated
so that the nat cache has its nid with an allocated block address.
In this procedure, previously we used
list_for_each_entry_safe(fnid, next_fnid, &nm_i->free_nid_list, list).
But, this is not covered by free_nid_list_lock, resulting in null pointer bug.
This patch moves this checking routine inside add_free_nid() in order not to use
the spin_lock.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
When nm_i->fcnt > 2 * MAX_FREE_NIDS, stop scanning other NAT entries.
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
[Jaegeuk Kim: fix handling the return value of add_free_nid()]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch does two cleanups:
1. remove unused variable "fcnt" in build_free_nids().
2. make scan_nat_page() as void type and remove useless variable "fcnt".
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Directly drop the free_nid cache when nm_i->fcnt > 2 * MAX_FREE_NIDS
Since there is NOT nmi->free_nid_list_lock spinlock protection between
a sequential calling of alloc_nid() and alloc_nid_failed(), some other
threads may already add new free_nid to the free_nid_list during this
period.
We need to make sure nmi->fcnt is never > 2 * MAX_FREE_NIDS.
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
[Jaegeuk Kim: fit the coding style]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
When testing f2fs on an SSD, I found some 128 page IOs followed by 1 page IO
were issued by f2fs_write_node_pages.
This means that there were some mishandling flows which degrades performance.
Previous f2fs_write_node_pages determines the number of pages to be written,
nr_to_write, as follows.
1. The bio_get_nr_vecs returns 129 pages.
2. The bio_alloc makes a room for 128 pages.
3. The initial 128 pages go into one bio.
4. The existing bio is submitted, and a new bio is prepared for the last 1 page.
5. Finally, sync_node_pages submits the last 1 page bio.
The problem is from the use of bio_get_nr_vecs, so this patch replace it
with max_hw_blocks using queue_max_sectors.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
try_to_free_nats() is usually called with parameter nr_shrink as
"nm_i->nat_cnt - NM_WOUT_THRESHOLD"
by flush_nat_entries() during checkpointing process.
However, this is inconsistent with the actual threshold check as
"if (nm_i->nat_cnt < 2 * NM_WOUT_THRESHOLD)"
, which will ignore the free_nats requests when
NM_WOUT_THRESHOLD < nm_i->nat_cnt < 2 * NM_WOUT_THRESHOLD
So fix the threshold check condition.
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
We call lock_page when we need to update a page after readpage.
Between grab and lock page, the page can be truncated by other thread.
So, we should check the page after lock_page whether it was truncated or not.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In order to avoid build_free_nid lock contention, let's change the order of
function calls as follows.
At first, check whether there is enough free nids.
- If available, just get a free nid with spin_lock without any overhead.
- Otherwise, conduct build_free_nids.
: scan nat pages, journal nat entries, and nat cache entries.
We should consider carefullly not to serve free nids intermediately made by
build_free_nids.
We can get stable free nids only after build_free_nids is done.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
It is more obvious that add_free_nid checks whether the free nid is zero or not.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
add tracepoints for tracing the truncate operations
like truncate node/data blocks, f2fs_truncate etc.
Tracepoints are added at entry and exit of operation
to trace the success & failure of operation.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In the previous version, f2fs uses global locks according to the usage types,
such as directory operations, block allocation, block write, and so on.
Reference the following lock types in f2fs.h.
enum lock_type {
RENAME, /* for renaming operations */
DENTRY_OPS, /* for directory operations */
DATA_WRITE, /* for data write */
DATA_NEW, /* for data allocation */
DATA_TRUNC, /* for data truncate */
NODE_NEW, /* for node allocation */
NODE_TRUNC, /* for node truncate */
NODE_WRITE, /* for node write */
NR_LOCK_TYPE,
};
In that case, we lose the performance under the multi-threading environment,
since every types of operations must be conducted one at a time.
In order to address the problem, let's share the locks globally with a mutex
array regardless of any types.
So, let users grab a mutex and perform their jobs in parallel as much as
possbile.
For this, I propose a new global lock scheme as follows.
0. Data structure
- f2fs_sb_info -> mutex_lock[NR_GLOBAL_LOCKS]
- f2fs_sb_info -> node_write
1. mutex_lock_op(sbi)
- try to get an avaiable lock from the array.
- returns the index of the gottern lock variable.
2. mutex_unlock_op(sbi, index of the lock)
- unlock the given index of the lock.
3. mutex_lock_all(sbi)
- grab all the locks in the array before the checkpoint.
4. mutex_unlock_all(sbi)
- release all the locks in the array after checkpoint.
5. block_operations()
- call mutex_lock_all()
- sync_dirty_dir_inodes()
- grab node_write
- sync_node_pages()
Note that,
the pairs of mutex_lock_op()/mutex_unlock_op() and
mutex_lock_all()/mutex_unlock_all() should be used together.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch reduces redundant spin_lock operations in alloc_nid_failed().
The alloc_nid_failed() does not need to delete entry and add one again
by triggering spin_lock and spin_unlock redundantly.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In order to do GC more reliably, I'd like to lock the vicitm summary page
until its GC is completed, and also prevent any checkpoint process.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In get_node_page, we do not need to call lock_page all the time.
If the node page is cached as uptodate,
1. grab_cache_page locks the page,
2. read_node_page unlocks the page, and
3. lock_page is called for further process.
Let's avoid this.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Use kmemdup instead of kzalloc and memcpy.
Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Acked-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In the checkpoint flow, the f2fs investigates the total nat cache entries.
Previously, if an entry has NULL_ADDR, f2fs drops the entry and adds the
obsolete nid to the free nid list.
However, this free nid will be reused sooner, resulting in its nat entry miss.
In order to avoid this, we don't need to drop the nat cache entry at this moment.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The build_free_nid should not add free nids over nm_i->max_nid.
But, there was a hole that invalid free nid was added by the following scenario.
Let's suppose nm_i->max_nid = 150 and the last NAT page has 100 ~ 200 nids.
build_free_nids
- get_current_nat_page loads the last NAT page
- scan_nat_page can add 100 ~ 200 nids
-> Bug here!
So, when scanning an NAT page, we should check each candidate whether it is
over max_nid or not.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If the return value of releasepage is equal to zero, the page cannot be reclaimed.
Instead, we should return 1 in order to reclaim clean pages.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
When we build new free nids, let's scan the just next NAT page instead of
skipping a couple of previously scanned pages in order to reuse free nids in
there.
Otherwise, we can use too much wide range of nids even though several nids were
deallocated, and also their node pages can be cached in the node_inode's address
space.
This means that we can retain lots of clean pages in the main memory, which
induces mm's reclaiming overhead.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
