davidlt/kernel-ark
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
946880fa27
kernel-ark/fs/nilfs2/the_nilfs.h

334 lines
10 KiB
C
Raw Normal View History

nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
/*
* the_nilfs.h - the_nilfs shared structure.
*
* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Written by Ryusuke Konishi <ryusuke@osrg.net>
*
*/
#ifndef _THE_NILFS_H
#define _THE_NILFS_H
#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
#include "sb.h"
/* the_nilfs struct */
enum {
THE_NILFS_INIT = 0, /* Information from super_block is set */
THE_NILFS_LOADED, /* Roll-back/roll-forward has done and
the latest checkpoint was loaded */
THE_NILFS_DISCONTINUED, /* 'next' pointer chain has broken */
nilfs2: shorten freeze period due to GC in write operation v3 This is a re-revised patch to shorten freeze period. This version include a fix of the bug Konishi-san mentioned last time. When GC is runnning, GC moves live block to difference segments. Copying live blocks into memory is done in a transaction, however it is not necessarily to be in the transaction. This patch will get the nilfs_ioctl_move_blocks() out from transaction lock and put it before the transaction. I ran sysbench fileio test against nilfs partition. I copied some DVD/CD images and created snapshot to create live blocks before starting the benchmark. Followings are summary of rc8 and rc8 w/ the patch of per-request statistics, which is min/max and avg. I ran each test three times and bellow is average of those numers. According to this benchmark result, average time is slightly degrated. However, worstcase (max) result is significantly improved. This can address a few seconds write freeze. - random write per-request performance of rc8 min 0.843ms max 680.406ms avg 3.050ms - random write per-request performance of rc8 w/ this patch min 0.843ms -> 100.00% max 380.490ms -> 55.90% avg 3.233ms -> 106.00% - sequential write per-request performance of rc8 min 0.736ms max 774.343ms avg 2.883ms - sequential write per-request performance of rc8 w/ this patch min 0.720ms -> 97.80% max 644.280ms-> 83.20% avg 3.130ms -> 108.50% -----8<-----8<-----nilfs_cleanerd.conf-----8<-----8<----- protection_period 150 selection_policy timestamp # timestamp in ascend order nsegments_per_clean 2 cleaning_interval 2 retry_interval 60 use_mmap log_priority info -----8<-----8<-----nilfs_cleanerd.conf-----8<-----8<----- Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-03 13:24:17 +00:00
THE_NILFS_GC_RUNNING, /* gc process is running */
nilfs2: get rid of s_dirt flag use This replaces s_dirt flag use in nilfs with a new flag added on the nilfs object. The s_dirt flag was used to indicate if sop->write_super() should be called, however the current version of nilfs does not use the callback. Thus, it can be replaced with the own flag. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Jiro SEKIBA <jir@unicus.jp>
2009-12-08 15:57:52 +00:00
THE_NILFS_SB_DIRTY, /* super block is dirty */
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
};
/**
* struct the_nilfs - struct to supervise multiple nilfs mount points
* @ns_flags: flags
* @ns_count: reference count
nilfs2: get rid of sget use for acquiring nilfs object This will change the way to obtain nilfs object in nilfs_get_sb() function. Previously, a preliminary sget() call was performed, and the nilfs object was acquired from a super block instance found by the sget() call. This patch, instead, instroduces a new dedicated function find_or_create_nilfs(); as the name implies, the function finds an existent nilfs object from a global list or creates a new one if no object is found on the device. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:29 +00:00
* @ns_list: list head for nilfs_list
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
* @ns_bdev: block device
* @ns_bdi: backing dev info
* @ns_writer: back pointer to writable nilfs_sb_info
* @ns_sem: semaphore for shared states
nilfs2: correct exclusion control in nilfs_remount function nilfs_remount() changes mount state of a superblock instance. Even though nilfs accesses other superblock instances during mount or remount, the mount state was not properly protected in nilfs_remount(). Moreover, nilfs_remount() has a lock order reversal problem; nilfs_get_sb() holds: 1. bdev->bd_mount_sem 2. sb->s_umount (sget acquires) and nilfs_remount() holds: 1. sb->s_umount (locked by the caller in vfs) 2. bdev->bd_mount_sem To avoid these problems, this patch divides a semaphore protecting super block instances from nilfs->ns_sem, and applies it to the mount state protection in nilfs_remount(). With this change, bd_mount_sem use is removed from nilfs_remount() and the lock order reversal will be resolved. And the new rw-semaphore, nilfs->ns_super_sem will properly protect the mount state except the modification from nilfs_error function. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:32 +00:00
* @ns_super_sem: semaphore for global operations across super block instances
nilfs2: get rid of bd_mount_sem use from nilfs This will remove every bd_mount_sem use in nilfs. The intended exclusion control was replaced by the previous patch ("nilfs2: correct exclusion control in nilfs_remount function") for nilfs_remount(), and this patch will replace remains with a new mutex that this inserts in nilfs object. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:33 +00:00
* @ns_mount_mutex: mutex protecting mount process of nilfs
nilfs2: use semaphore to protect pointer to a writable FS-instance will get rid of nilfs_get_writer() and nilfs_put_writer() pair used to retain a writable FS-instance for a period. The pair functions were making up some kind of recursive lock with a mutex, but they became overkill since the commit 201913ed746c7724a40d33ee5a0b6a1fd2ef3193. Furthermore, they caused the following lockdep warning because the mutex can be released by a task which didn't lock it: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- kswapd0/422 is trying to release lock (&nilfs->ns_writer_mutex) at: [<c1359ff5>] mutex_unlock+0x8/0xa but there are no more locks to release! other info that might help us debug this: no locks held by kswapd0/422. stack backtrace: Pid: 422, comm: kswapd0 Not tainted 2.6.31-rc4-nilfs #51 Call Trace: [<c1358f97>] ? printk+0xf/0x18 [<c104fea7>] print_unlock_inbalance_bug+0xcc/0xd7 [<c11578de>] ? prop_put_global+0x3/0x35 [<c1050195>] lock_release+0xed/0x1dc [<c1359ff5>] ? mutex_unlock+0x8/0xa [<c1359f83>] __mutex_unlock_slowpath+0xaf/0x119 [<c1359ff5>] mutex_unlock+0x8/0xa [<d1284add>] nilfs_mdt_write_page+0xd8/0xe1 [nilfs2] [<c1092653>] shrink_page_list+0x379/0x68d [<c109171b>] ? isolate_pages_global+0xb4/0x18c [<c1092bd2>] shrink_list+0x26b/0x54b [<c10930be>] shrink_zone+0x20c/0x2a2 [<c10936b7>] kswapd+0x407/0x591 [<c1091667>] ? isolate_pages_global+0x0/0x18c [<c1040603>] ? autoremove_wake_function+0x0/0x33 [<c10932b0>] ? kswapd+0x0/0x591 [<c104033b>] kthread+0x69/0x6e [<c10402d2>] ? kthread+0x0/0x6e [<c1003e33>] kernel_thread_helper+0x7/0x1a This patch uses a reader/writer semaphore instead of the own lock and kills this warning. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-02 13:45:33 +00:00
* @ns_writer_sem: semaphore protecting ns_writer attach/detach
nilfs2: get rid of sget use for checking if current mount is present This stops using sget() for checking if an r/w-mount or an r/o-mount exists on the device. This elimination uses a back pointer to the current mount added to nilfs object. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:30 +00:00
* @ns_current: back pointer to current mount
nilfs2: introduce secondary super block The former versions didn't have extra super blocks. This improves the weak point by introducing another super block at unused region in tail of the partition. This doesn't break disk format compatibility; older versions just ingore the secondary super block, and new versions just recover it if it doesn't exist. The partition created by an old mkfs may not have unused region, but in that case, the secondary super block will not be added. This doesn't make more redundant copies of the super block; it is a future work. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:59 +00:00
* @ns_sbh: buffer heads of on-disk super blocks
* @ns_sbp: pointers to super block data
nilfs2: sync super blocks in turns This will sync super blocks in turns instead of syncing duplicate super blocks at the time. This will help searching valid super root when super block is written into disk before log is written, which is happen when barrier-less block devices are unmounted uncleanly. In the situation, old super block likely points to valid log. This patch introduces ns_sbwcount member to the nilfs object and adds nilfs_sb_will_flip() function; ns_sbwcount counts how many times super blocks write back to the disk. And, nilfs_sb_will_flip() decides whether flipping required or not based on the count of ns_sbwcount to sync super blocks asymmetrically. The following functions are also changed: - nilfs_prepare_super(): flips super blocks according to the argument. The argument is calculated by nilfs_sb_will_flip() function. - nilfs_cleanup_super(): sets "clean" flag to both super blocks if they point to the same checkpoint. To update both of super block information, caller of nilfs_commit_super must set the information on both super blocks. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-06-28 08:49:33 +00:00
* @ns_sbwtime: previous write time of super block
* @ns_sbwcount: write count of super block
nilfs2: introduce secondary super block The former versions didn't have extra super blocks. This improves the weak point by introducing another super block at unused region in tail of the partition. This doesn't break disk format compatibility; older versions just ingore the secondary super block, and new versions just recover it if it doesn't exist. The partition created by an old mkfs may not have unused region, but in that case, the secondary super block will not be added. This doesn't make more redundant copies of the super block; it is a future work. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:59 +00:00
* @ns_sbsize: size of valid data in super block
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
* @ns_supers: list of nilfs super block structs
* @ns_seg_seq: segment sequence counter
* @ns_segnum: index number of the latest full segment.
* @ns_nextnum: index number of the full segment index to be used next
* @ns_pseg_offset: offset of next partial segment in the current full segment
* @ns_cno: next checkpoint number
* @ns_ctime: write time of the last segment
* @ns_nongc_ctime: write time of the last segment not for cleaner operation
* @ns_ndirtyblks: Number of dirty data blocks
* @ns_last_segment_lock: lock protecting fields for the latest segment
* @ns_last_pseg: start block number of the latest segment
* @ns_last_seq: sequence value of the latest segment
* @ns_last_cno: checkpoint number of the latest segment
nilfs2: extend nilfs_sustat ioctl struct This adds a new argument to the nilfs_sustat structure. The extended field allows to delete volatile active state of segments, which was needed to protect freshly-created segments from garbage collection but has confused code dealing with segments. This extension alleviates the mess and gives room for further simplifications. The volatile active flag is not persistent, so it's eliminable on this occasion without affecting compatibility other than the ioctl change. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:54 +00:00
* @ns_prot_seq: least sequence number of segments which must not be reclaimed
nilfs2: do not update log cursor for small change Super blocks of nilfs are periodically overwritten in order to record the recent log position. This shortens recovery time after unclean unmount, but the current implementation performs the update even for a few blocks of change. If the filesystem gets small changes slowly and continually, super blocks may be updated excessively. This moderates the issue by skipping update of log cursor if it does not cross a segment boundary. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-06-29 05:42:13 +00:00
* @ns_prev_seq: base sequence number used to decide if advance log cursor
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
* @ns_segctor_sem: segment constructor semaphore
* @ns_dat: DAT file inode
* @ns_cpfile: checkpoint file inode
* @ns_sufile: segusage file inode
* @ns_gc_dat: shadow inode of the DAT file inode for GC
* @ns_gc_inodes: dummy inodes to keep live blocks
* @ns_gc_inodes_h: hash list to keep dummy inode holding live blocks
* @ns_blocksize_bits: bit length of block size
nilfs2: add blocksize member to nilfs object This stores blocksize in nilfs objects for the successive refactoring of recovery logic. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-22 15:17:48 +00:00
* @ns_blocksize: block size
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
* @ns_nsegments: number of segments in filesystem
* @ns_blocks_per_segment: number of blocks per segment
* @ns_r_segments_percentage: reserved segments percentage
* @ns_nrsvsegs: number of reserved segments
* @ns_first_data_block: block number of first data block
* @ns_inode_size: size of on-disk inode
* @ns_first_ino: first not-special inode number
* @ns_crc_seed: seed value of CRC32 calculation
*/
struct the_nilfs {
unsigned long ns_flags;
atomic_t ns_count;
nilfs2: get rid of sget use for acquiring nilfs object This will change the way to obtain nilfs object in nilfs_get_sb() function. Previously, a preliminary sget() call was performed, and the nilfs object was acquired from a super block instance found by the sget() call. This patch, instead, instroduces a new dedicated function find_or_create_nilfs(); as the name implies, the function finds an existent nilfs object from a global list or creates a new one if no object is found on the device. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:29 +00:00
struct list_head ns_list;
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
struct block_device *ns_bdev;
struct backing_dev_info *ns_bdi;
struct nilfs_sb_info *ns_writer;
struct rw_semaphore ns_sem;
nilfs2: correct exclusion control in nilfs_remount function nilfs_remount() changes mount state of a superblock instance. Even though nilfs accesses other superblock instances during mount or remount, the mount state was not properly protected in nilfs_remount(). Moreover, nilfs_remount() has a lock order reversal problem; nilfs_get_sb() holds: 1. bdev->bd_mount_sem 2. sb->s_umount (sget acquires) and nilfs_remount() holds: 1. sb->s_umount (locked by the caller in vfs) 2. bdev->bd_mount_sem To avoid these problems, this patch divides a semaphore protecting super block instances from nilfs->ns_sem, and applies it to the mount state protection in nilfs_remount(). With this change, bd_mount_sem use is removed from nilfs_remount() and the lock order reversal will be resolved. And the new rw-semaphore, nilfs->ns_super_sem will properly protect the mount state except the modification from nilfs_error function. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:32 +00:00
struct rw_semaphore ns_super_sem;
nilfs2: get rid of bd_mount_sem use from nilfs This will remove every bd_mount_sem use in nilfs. The intended exclusion control was replaced by the previous patch ("nilfs2: correct exclusion control in nilfs_remount function") for nilfs_remount(), and this patch will replace remains with a new mutex that this inserts in nilfs object. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:33 +00:00
struct mutex ns_mount_mutex;
nilfs2: use semaphore to protect pointer to a writable FS-instance will get rid of nilfs_get_writer() and nilfs_put_writer() pair used to retain a writable FS-instance for a period. The pair functions were making up some kind of recursive lock with a mutex, but they became overkill since the commit 201913ed746c7724a40d33ee5a0b6a1fd2ef3193. Furthermore, they caused the following lockdep warning because the mutex can be released by a task which didn't lock it: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- kswapd0/422 is trying to release lock (&nilfs->ns_writer_mutex) at: [<c1359ff5>] mutex_unlock+0x8/0xa but there are no more locks to release! other info that might help us debug this: no locks held by kswapd0/422. stack backtrace: Pid: 422, comm: kswapd0 Not tainted 2.6.31-rc4-nilfs #51 Call Trace: [<c1358f97>] ? printk+0xf/0x18 [<c104fea7>] print_unlock_inbalance_bug+0xcc/0xd7 [<c11578de>] ? prop_put_global+0x3/0x35 [<c1050195>] lock_release+0xed/0x1dc [<c1359ff5>] ? mutex_unlock+0x8/0xa [<c1359f83>] __mutex_unlock_slowpath+0xaf/0x119 [<c1359ff5>] mutex_unlock+0x8/0xa [<d1284add>] nilfs_mdt_write_page+0xd8/0xe1 [nilfs2] [<c1092653>] shrink_page_list+0x379/0x68d [<c109171b>] ? isolate_pages_global+0xb4/0x18c [<c1092bd2>] shrink_list+0x26b/0x54b [<c10930be>] shrink_zone+0x20c/0x2a2 [<c10936b7>] kswapd+0x407/0x591 [<c1091667>] ? isolate_pages_global+0x0/0x18c [<c1040603>] ? autoremove_wake_function+0x0/0x33 [<c10932b0>] ? kswapd+0x0/0x591 [<c104033b>] kthread+0x69/0x6e [<c10402d2>] ? kthread+0x0/0x6e [<c1003e33>] kernel_thread_helper+0x7/0x1a This patch uses a reader/writer semaphore instead of the own lock and kills this warning. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-02 13:45:33 +00:00
struct rw_semaphore ns_writer_sem;
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
nilfs2: correct exclusion control in nilfs_remount function nilfs_remount() changes mount state of a superblock instance. Even though nilfs accesses other superblock instances during mount or remount, the mount state was not properly protected in nilfs_remount(). Moreover, nilfs_remount() has a lock order reversal problem; nilfs_get_sb() holds: 1. bdev->bd_mount_sem 2. sb->s_umount (sget acquires) and nilfs_remount() holds: 1. sb->s_umount (locked by the caller in vfs) 2. bdev->bd_mount_sem To avoid these problems, this patch divides a semaphore protecting super block instances from nilfs->ns_sem, and applies it to the mount state protection in nilfs_remount(). With this change, bd_mount_sem use is removed from nilfs_remount() and the lock order reversal will be resolved. And the new rw-semaphore, nilfs->ns_super_sem will properly protect the mount state except the modification from nilfs_error function. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:32 +00:00
/*
* components protected by ns_super_sem
*/
nilfs2: get rid of sget use for checking if current mount is present This stops using sget() for checking if an r/w-mount or an r/o-mount exists on the device. This elimination uses a back pointer to the current mount added to nilfs object. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:30 +00:00
struct nilfs_sb_info *ns_current;
nilfs2: correct exclusion control in nilfs_remount function nilfs_remount() changes mount state of a superblock instance. Even though nilfs accesses other superblock instances during mount or remount, the mount state was not properly protected in nilfs_remount(). Moreover, nilfs_remount() has a lock order reversal problem; nilfs_get_sb() holds: 1. bdev->bd_mount_sem 2. sb->s_umount (sget acquires) and nilfs_remount() holds: 1. sb->s_umount (locked by the caller in vfs) 2. bdev->bd_mount_sem To avoid these problems, this patch divides a semaphore protecting super block instances from nilfs->ns_sem, and applies it to the mount state protection in nilfs_remount(). With this change, bd_mount_sem use is removed from nilfs_remount() and the lock order reversal will be resolved. And the new rw-semaphore, nilfs->ns_super_sem will properly protect the mount state except the modification from nilfs_error function. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:32 +00:00
struct list_head ns_supers;
nilfs2: get rid of sget use for checking if current mount is present This stops using sget() for checking if an r/w-mount or an r/o-mount exists on the device. This elimination uses a back pointer to the current mount added to nilfs object. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:30 +00:00
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
/*
* used for
* - loading the latest checkpoint exclusively.
* - allocating a new full segment.
* - protecting s_dirt in the super_block struct
* (see nilfs_write_super) and the following fields.
*/
nilfs2: introduce secondary super block The former versions didn't have extra super blocks. This improves the weak point by introducing another super block at unused region in tail of the partition. This doesn't break disk format compatibility; older versions just ingore the secondary super block, and new versions just recover it if it doesn't exist. The partition created by an old mkfs may not have unused region, but in that case, the secondary super block will not be added. This doesn't make more redundant copies of the super block; it is a future work. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:59 +00:00
struct buffer_head *ns_sbh[2];
struct nilfs_super_block *ns_sbp[2];
nilfs2: sync super blocks in turns This will sync super blocks in turns instead of syncing duplicate super blocks at the time. This will help searching valid super root when super block is written into disk before log is written, which is happen when barrier-less block devices are unmounted uncleanly. In the situation, old super block likely points to valid log. This patch introduces ns_sbwcount member to the nilfs object and adds nilfs_sb_will_flip() function; ns_sbwcount counts how many times super blocks write back to the disk. And, nilfs_sb_will_flip() decides whether flipping required or not based on the count of ns_sbwcount to sync super blocks asymmetrically. The following functions are also changed: - nilfs_prepare_super(): flips super blocks according to the argument. The argument is calculated by nilfs_sb_will_flip() function. - nilfs_cleanup_super(): sets "clean" flag to both super blocks if they point to the same checkpoint. To update both of super block information, caller of nilfs_commit_super must set the information on both super blocks. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-06-28 08:49:33 +00:00
time_t ns_sbwtime;
unsigned ns_sbwcount;
nilfs2: introduce secondary super block The former versions didn't have extra super blocks. This improves the weak point by introducing another super block at unused region in tail of the partition. This doesn't break disk format compatibility; older versions just ingore the secondary super block, and new versions just recover it if it doesn't exist. The partition created by an old mkfs may not have unused region, but in that case, the secondary super block will not be added. This doesn't make more redundant copies of the super block; it is a future work. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:59 +00:00
unsigned ns_sbsize;
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
unsigned ns_mount_state;
/*
* Following fields are dedicated to a writable FS-instance.
* Except for the period seeking checkpoint, code outside the segment
nilfs2: avoid double error caused by nilfs_transaction_end Pekka Enberg pointed out that double error handlings found after nilfs_transaction_end() can be avoided by separating abort operation: OK, I don't understand this. The only way nilfs_transaction_end() can fail is if we have NILFS_TI_SYNC set and we fail to construct the segment. But why do we want to construct a segment if we don't commit? I guess what I'm asking is why don't we have a separate nilfs_transaction_abort() function that can't fail for the erroneous case to avoid this double error value tracking thing? This does the separation and renames nilfs_transaction_end() to nilfs_transaction_commit() for clarification. Since, some calls of these functions were used just for exclusion control against the segment constructor, they are replaced with semaphore operations. Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:45 +00:00
* constructor must lock a segment semaphore while accessing these
* fields.
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
* The writable FS-instance is sole during a lifetime of the_nilfs.
*/
u64 ns_seg_seq;
__u64 ns_segnum;
__u64 ns_nextnum;
unsigned long ns_pseg_offset;
__u64 ns_cno;
time_t ns_ctime;
time_t ns_nongc_ctime;
atomic_t ns_ndirtyblks;
/*
* The following fields hold information on the latest partial segment
* written to disk with a super root. These fields are protected by
* ns_last_segment_lock.
*/
spinlock_t ns_last_segment_lock;
sector_t ns_last_pseg;
u64 ns_last_seq;
__u64 ns_last_cno;
nilfs2: extend nilfs_sustat ioctl struct This adds a new argument to the nilfs_sustat structure. The extended field allows to delete volatile active state of segments, which was needed to protect freshly-created segments from garbage collection but has confused code dealing with segments. This extension alleviates the mess and gives room for further simplifications. The volatile active flag is not persistent, so it's eliminable on this occasion without affecting compatibility other than the ioctl change. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:54 +00:00
u64 ns_prot_seq;
nilfs2: do not update log cursor for small change Super blocks of nilfs are periodically overwritten in order to record the recent log position. This shortens recovery time after unclean unmount, but the current implementation performs the update even for a few blocks of change. If the filesystem gets small changes slowly and continually, super blocks may be updated excessively. This moderates the issue by skipping update of log cursor if it does not cross a segment boundary. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-06-29 05:42:13 +00:00
u64 ns_prev_seq;
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
struct rw_semaphore ns_segctor_sem;
/*
* Following fields are lock free except for the period before
* the_nilfs is initialized.
*/
struct inode *ns_dat;
struct inode *ns_cpfile;
struct inode *ns_sufile;
struct inode *ns_gc_dat;
/* GC inode list and hash table head */
struct list_head ns_gc_inodes;
struct hlist_head *ns_gc_inodes_h;
/* Disk layout information (static) */
unsigned int ns_blocksize_bits;
nilfs2: add blocksize member to nilfs object This stores blocksize in nilfs objects for the successive refactoring of recovery logic. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-22 15:17:48 +00:00
unsigned int ns_blocksize;
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
unsigned long ns_nsegments;
unsigned long ns_blocks_per_segment;
unsigned long ns_r_segments_percentage;
unsigned long ns_nrsvsegs;
unsigned long ns_first_data_block;
int ns_inode_size;
int ns_first_ino;
u32 ns_crc_seed;
};
#define NILFS_GCINODE_HASH_BITS 8
#define NILFS_GCINODE_HASH_SIZE (1<<NILFS_GCINODE_HASH_BITS)
#define THE_NILFS_FNS(bit, name) \
static inline void set_nilfs_##name(struct the_nilfs *nilfs) \
{ \
set_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
} \
static inline void clear_nilfs_##name(struct the_nilfs *nilfs) \
{ \
clear_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
} \
static inline int nilfs_##name(struct the_nilfs *nilfs) \
{ \
return test_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
}
THE_NILFS_FNS(INIT, init)
THE_NILFS_FNS(LOADED, loaded)
THE_NILFS_FNS(DISCONTINUED, discontinued)
nilfs2: shorten freeze period due to GC in write operation v3 This is a re-revised patch to shorten freeze period. This version include a fix of the bug Konishi-san mentioned last time. When GC is runnning, GC moves live block to difference segments. Copying live blocks into memory is done in a transaction, however it is not necessarily to be in the transaction. This patch will get the nilfs_ioctl_move_blocks() out from transaction lock and put it before the transaction. I ran sysbench fileio test against nilfs partition. I copied some DVD/CD images and created snapshot to create live blocks before starting the benchmark. Followings are summary of rc8 and rc8 w/ the patch of per-request statistics, which is min/max and avg. I ran each test three times and bellow is average of those numers. According to this benchmark result, average time is slightly degrated. However, worstcase (max) result is significantly improved. This can address a few seconds write freeze. - random write per-request performance of rc8 min 0.843ms max 680.406ms avg 3.050ms - random write per-request performance of rc8 w/ this patch min 0.843ms -> 100.00% max 380.490ms -> 55.90% avg 3.233ms -> 106.00% - sequential write per-request performance of rc8 min 0.736ms max 774.343ms avg 2.883ms - sequential write per-request performance of rc8 w/ this patch min 0.720ms -> 97.80% max 644.280ms-> 83.20% avg 3.130ms -> 108.50% -----8<-----8<-----nilfs_cleanerd.conf-----8<-----8<----- protection_period 150 selection_policy timestamp # timestamp in ascend order nsegments_per_clean 2 cleaning_interval 2 retry_interval 60 use_mmap log_priority info -----8<-----8<-----nilfs_cleanerd.conf-----8<-----8<----- Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-09-03 13:24:17 +00:00
THE_NILFS_FNS(GC_RUNNING, gc_running)
nilfs2: get rid of s_dirt flag use This replaces s_dirt flag use in nilfs with a new flag added on the nilfs object. The s_dirt flag was used to indicate if sop->write_super() should be called, however the current version of nilfs does not use the callback. Thus, it can be replaced with the own flag. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Jiro SEKIBA <jir@unicus.jp>
2009-12-08 15:57:52 +00:00
THE_NILFS_FNS(SB_DIRTY, sb_dirty)
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
nilfs2: introduce secondary super block The former versions didn't have extra super blocks. This improves the weak point by introducing another super block at unused region in tail of the partition. This doesn't break disk format compatibility; older versions just ingore the secondary super block, and new versions just recover it if it doesn't exist. The partition created by an old mkfs may not have unused region, but in that case, the secondary super block will not be added. This doesn't make more redundant copies of the super block; it is a future work. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:59 +00:00
/* Minimum interval of periodical update of superblocks (in seconds) */
#define NILFS_SB_FREQ 10
nilfs2: clean up nilfs_write_super Separate conditions that check if syncing super block and alternative super block are required as inline functions to reuse the conditions. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-07-22 16:26:34 +00:00
static inline int nilfs_sb_need_update(struct the_nilfs *nilfs)
{
u64 t = get_seconds();
nilfs2: sync super blocks in turns This will sync super blocks in turns instead of syncing duplicate super blocks at the time. This will help searching valid super root when super block is written into disk before log is written, which is happen when barrier-less block devices are unmounted uncleanly. In the situation, old super block likely points to valid log. This patch introduces ns_sbwcount member to the nilfs object and adds nilfs_sb_will_flip() function; ns_sbwcount counts how many times super blocks write back to the disk. And, nilfs_sb_will_flip() decides whether flipping required or not based on the count of ns_sbwcount to sync super blocks asymmetrically. The following functions are also changed: - nilfs_prepare_super(): flips super blocks according to the argument. The argument is calculated by nilfs_sb_will_flip() function. - nilfs_cleanup_super(): sets "clean" flag to both super blocks if they point to the same checkpoint. To update both of super block information, caller of nilfs_commit_super must set the information on both super blocks. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-06-28 08:49:33 +00:00
return t < nilfs->ns_sbwtime || t > nilfs->ns_sbwtime + NILFS_SB_FREQ;
nilfs2: clean up nilfs_write_super Separate conditions that check if syncing super block and alternative super block are required as inline functions to reuse the conditions. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-07-22 16:26:34 +00:00
}
nilfs2: sync super blocks in turns This will sync super blocks in turns instead of syncing duplicate super blocks at the time. This will help searching valid super root when super block is written into disk before log is written, which is happen when barrier-less block devices are unmounted uncleanly. In the situation, old super block likely points to valid log. This patch introduces ns_sbwcount member to the nilfs object and adds nilfs_sb_will_flip() function; ns_sbwcount counts how many times super blocks write back to the disk. And, nilfs_sb_will_flip() decides whether flipping required or not based on the count of ns_sbwcount to sync super blocks asymmetrically. The following functions are also changed: - nilfs_prepare_super(): flips super blocks according to the argument. The argument is calculated by nilfs_sb_will_flip() function. - nilfs_cleanup_super(): sets "clean" flag to both super blocks if they point to the same checkpoint. To update both of super block information, caller of nilfs_commit_super must set the information on both super blocks. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-06-28 08:49:33 +00:00
static inline int nilfs_sb_will_flip(struct the_nilfs *nilfs)
nilfs2: clean up nilfs_write_super Separate conditions that check if syncing super block and alternative super block are required as inline functions to reuse the conditions. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-07-22 16:26:34 +00:00
{
nilfs2: sync super blocks in turns This will sync super blocks in turns instead of syncing duplicate super blocks at the time. This will help searching valid super root when super block is written into disk before log is written, which is happen when barrier-less block devices are unmounted uncleanly. In the situation, old super block likely points to valid log. This patch introduces ns_sbwcount member to the nilfs object and adds nilfs_sb_will_flip() function; ns_sbwcount counts how many times super blocks write back to the disk. And, nilfs_sb_will_flip() decides whether flipping required or not based on the count of ns_sbwcount to sync super blocks asymmetrically. The following functions are also changed: - nilfs_prepare_super(): flips super blocks according to the argument. The argument is calculated by nilfs_sb_will_flip() function. - nilfs_cleanup_super(): sets "clean" flag to both super blocks if they point to the same checkpoint. To update both of super block information, caller of nilfs_commit_super must set the information on both super blocks. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-06-28 08:49:33 +00:00
int flip_bits = nilfs->ns_sbwcount & 0x0FL;
return (flip_bits != 0x08 && flip_bits != 0x0F);
nilfs2: clean up nilfs_write_super Separate conditions that check if syncing super block and alternative super block are required as inline functions to reuse the conditions. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-07-22 16:26:34 +00:00
}
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
void nilfs_set_last_segment(struct the_nilfs *, sector_t, u64, __u64);
nilfs2: get rid of sget use for acquiring nilfs object This will change the way to obtain nilfs object in nilfs_get_sb() function. Previously, a preliminary sget() call was performed, and the nilfs object was acquired from a super block instance found by the sget() call. This patch, instead, instroduces a new dedicated function find_or_create_nilfs(); as the name implies, the function finds an existent nilfs object from a global list or creates a new one if no object is found on the device. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:29 +00:00
struct the_nilfs *find_or_create_nilfs(struct block_device *);
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
void put_nilfs(struct the_nilfs *);
int init_nilfs(struct the_nilfs *, struct nilfs_sb_info *, char *);
int load_nilfs(struct the_nilfs *, struct nilfs_sb_info *);
nilfs2: issue discard request after cleaning segments This adds a function to send discard requests for given array of segment numbers, and calls the function when garbage collection succeeded. Signed-off-by: Jiro SEKIBA <jir@unicus.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-01-30 09:06:35 +00:00
int nilfs_discard_segments(struct the_nilfs *, __u64 *, size_t);
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
int nilfs_count_free_blocks(struct the_nilfs *, sector_t *);
nilfs2: simplify remaining sget() use This simplifies the test function passed on the remaining sget() callsite in nilfs. Instead of checking mount type (i.e. ro-mount/rw-mount/snapshot mount) in the test function passed to sget(), this patch first looks up the nilfs_sb_info struct which the given mount type matches, and then acquires the super block instance holding the nilfs_sb_info. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:31 +00:00
struct nilfs_sb_info *nilfs_find_sbinfo(struct the_nilfs *, int, __u64);
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
int nilfs_checkpoint_is_mounted(struct the_nilfs *, __u64, int);
int nilfs_near_disk_full(struct the_nilfs *);
nilfs2: introduce secondary super block The former versions didn't have extra super blocks. This improves the weak point by introducing another super block at unused region in tail of the partition. This doesn't break disk format compatibility; older versions just ingore the secondary super block, and new versions just recover it if it doesn't exist. The partition created by an old mkfs may not have unused region, but in that case, the secondary super block will not be added. This doesn't make more redundant copies of the super block; it is a future work. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:59 +00:00
void nilfs_fall_back_super_block(struct the_nilfs *);
void nilfs_swap_super_block(struct the_nilfs *);
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
static inline void get_nilfs(struct the_nilfs *nilfs)
{
/* Caller must have at least one reference of the_nilfs. */
atomic_inc(&nilfs->ns_count);
}
static inline void
nilfs_attach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi)
{
nilfs2: use semaphore to protect pointer to a writable FS-instance will get rid of nilfs_get_writer() and nilfs_put_writer() pair used to retain a writable FS-instance for a period. The pair functions were making up some kind of recursive lock with a mutex, but they became overkill since the commit 201913ed746c7724a40d33ee5a0b6a1fd2ef3193. Furthermore, they caused the following lockdep warning because the mutex can be released by a task which didn't lock it: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- kswapd0/422 is trying to release lock (&nilfs->ns_writer_mutex) at: [<c1359ff5>] mutex_unlock+0x8/0xa but there are no more locks to release! other info that might help us debug this: no locks held by kswapd0/422. stack backtrace: Pid: 422, comm: kswapd0 Not tainted 2.6.31-rc4-nilfs #51 Call Trace: [<c1358f97>] ? printk+0xf/0x18 [<c104fea7>] print_unlock_inbalance_bug+0xcc/0xd7 [<c11578de>] ? prop_put_global+0x3/0x35 [<c1050195>] lock_release+0xed/0x1dc [<c1359ff5>] ? mutex_unlock+0x8/0xa [<c1359f83>] __mutex_unlock_slowpath+0xaf/0x119 [<c1359ff5>] mutex_unlock+0x8/0xa [<d1284add>] nilfs_mdt_write_page+0xd8/0xe1 [nilfs2] [<c1092653>] shrink_page_list+0x379/0x68d [<c109171b>] ? isolate_pages_global+0xb4/0x18c [<c1092bd2>] shrink_list+0x26b/0x54b [<c10930be>] shrink_zone+0x20c/0x2a2 [<c10936b7>] kswapd+0x407/0x591 [<c1091667>] ? isolate_pages_global+0x0/0x18c [<c1040603>] ? autoremove_wake_function+0x0/0x33 [<c10932b0>] ? kswapd+0x0/0x591 [<c104033b>] kthread+0x69/0x6e [<c10402d2>] ? kthread+0x0/0x6e [<c1003e33>] kernel_thread_helper+0x7/0x1a This patch uses a reader/writer semaphore instead of the own lock and kills this warning. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-02 13:45:33 +00:00
down_write(&nilfs->ns_writer_sem);
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
nilfs->ns_writer = sbi;
nilfs2: use semaphore to protect pointer to a writable FS-instance will get rid of nilfs_get_writer() and nilfs_put_writer() pair used to retain a writable FS-instance for a period. The pair functions were making up some kind of recursive lock with a mutex, but they became overkill since the commit 201913ed746c7724a40d33ee5a0b6a1fd2ef3193. Furthermore, they caused the following lockdep warning because the mutex can be released by a task which didn't lock it: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- kswapd0/422 is trying to release lock (&nilfs->ns_writer_mutex) at: [<c1359ff5>] mutex_unlock+0x8/0xa but there are no more locks to release! other info that might help us debug this: no locks held by kswapd0/422. stack backtrace: Pid: 422, comm: kswapd0 Not tainted 2.6.31-rc4-nilfs #51 Call Trace: [<c1358f97>] ? printk+0xf/0x18 [<c104fea7>] print_unlock_inbalance_bug+0xcc/0xd7 [<c11578de>] ? prop_put_global+0x3/0x35 [<c1050195>] lock_release+0xed/0x1dc [<c1359ff5>] ? mutex_unlock+0x8/0xa [<c1359f83>] __mutex_unlock_slowpath+0xaf/0x119 [<c1359ff5>] mutex_unlock+0x8/0xa [<d1284add>] nilfs_mdt_write_page+0xd8/0xe1 [nilfs2] [<c1092653>] shrink_page_list+0x379/0x68d [<c109171b>] ? isolate_pages_global+0xb4/0x18c [<c1092bd2>] shrink_list+0x26b/0x54b [<c10930be>] shrink_zone+0x20c/0x2a2 [<c10936b7>] kswapd+0x407/0x591 [<c1091667>] ? isolate_pages_global+0x0/0x18c [<c1040603>] ? autoremove_wake_function+0x0/0x33 [<c10932b0>] ? kswapd+0x0/0x591 [<c104033b>] kthread+0x69/0x6e [<c10402d2>] ? kthread+0x0/0x6e [<c1003e33>] kernel_thread_helper+0x7/0x1a This patch uses a reader/writer semaphore instead of the own lock and kills this warning. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-02 13:45:33 +00:00
up_write(&nilfs->ns_writer_sem);
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
}
static inline void
nilfs_detach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi)
{
nilfs2: use semaphore to protect pointer to a writable FS-instance will get rid of nilfs_get_writer() and nilfs_put_writer() pair used to retain a writable FS-instance for a period. The pair functions were making up some kind of recursive lock with a mutex, but they became overkill since the commit 201913ed746c7724a40d33ee5a0b6a1fd2ef3193. Furthermore, they caused the following lockdep warning because the mutex can be released by a task which didn't lock it: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- kswapd0/422 is trying to release lock (&nilfs->ns_writer_mutex) at: [<c1359ff5>] mutex_unlock+0x8/0xa but there are no more locks to release! other info that might help us debug this: no locks held by kswapd0/422. stack backtrace: Pid: 422, comm: kswapd0 Not tainted 2.6.31-rc4-nilfs #51 Call Trace: [<c1358f97>] ? printk+0xf/0x18 [<c104fea7>] print_unlock_inbalance_bug+0xcc/0xd7 [<c11578de>] ? prop_put_global+0x3/0x35 [<c1050195>] lock_release+0xed/0x1dc [<c1359ff5>] ? mutex_unlock+0x8/0xa [<c1359f83>] __mutex_unlock_slowpath+0xaf/0x119 [<c1359ff5>] mutex_unlock+0x8/0xa [<d1284add>] nilfs_mdt_write_page+0xd8/0xe1 [nilfs2] [<c1092653>] shrink_page_list+0x379/0x68d [<c109171b>] ? isolate_pages_global+0xb4/0x18c [<c1092bd2>] shrink_list+0x26b/0x54b [<c10930be>] shrink_zone+0x20c/0x2a2 [<c10936b7>] kswapd+0x407/0x591 [<c1091667>] ? isolate_pages_global+0x0/0x18c [<c1040603>] ? autoremove_wake_function+0x0/0x33 [<c10932b0>] ? kswapd+0x0/0x591 [<c104033b>] kthread+0x69/0x6e [<c10402d2>] ? kthread+0x0/0x6e [<c1003e33>] kernel_thread_helper+0x7/0x1a This patch uses a reader/writer semaphore instead of the own lock and kills this warning. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-02 13:45:33 +00:00
down_write(&nilfs->ns_writer_sem);
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
if (sbi == nilfs->ns_writer)
nilfs->ns_writer = NULL;
nilfs2: use semaphore to protect pointer to a writable FS-instance will get rid of nilfs_get_writer() and nilfs_put_writer() pair used to retain a writable FS-instance for a period. The pair functions were making up some kind of recursive lock with a mutex, but they became overkill since the commit 201913ed746c7724a40d33ee5a0b6a1fd2ef3193. Furthermore, they caused the following lockdep warning because the mutex can be released by a task which didn't lock it: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- kswapd0/422 is trying to release lock (&nilfs->ns_writer_mutex) at: [<c1359ff5>] mutex_unlock+0x8/0xa but there are no more locks to release! other info that might help us debug this: no locks held by kswapd0/422. stack backtrace: Pid: 422, comm: kswapd0 Not tainted 2.6.31-rc4-nilfs #51 Call Trace: [<c1358f97>] ? printk+0xf/0x18 [<c104fea7>] print_unlock_inbalance_bug+0xcc/0xd7 [<c11578de>] ? prop_put_global+0x3/0x35 [<c1050195>] lock_release+0xed/0x1dc [<c1359ff5>] ? mutex_unlock+0x8/0xa [<c1359f83>] __mutex_unlock_slowpath+0xaf/0x119 [<c1359ff5>] mutex_unlock+0x8/0xa [<d1284add>] nilfs_mdt_write_page+0xd8/0xe1 [nilfs2] [<c1092653>] shrink_page_list+0x379/0x68d [<c109171b>] ? isolate_pages_global+0xb4/0x18c [<c1092bd2>] shrink_list+0x26b/0x54b [<c10930be>] shrink_zone+0x20c/0x2a2 [<c10936b7>] kswapd+0x407/0x591 [<c1091667>] ? isolate_pages_global+0x0/0x18c [<c1040603>] ? autoremove_wake_function+0x0/0x33 [<c10932b0>] ? kswapd+0x0/0x591 [<c104033b>] kthread+0x69/0x6e [<c10402d2>] ? kthread+0x0/0x6e [<c1003e33>] kernel_thread_helper+0x7/0x1a This patch uses a reader/writer semaphore instead of the own lock and kills this warning. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-02 13:45:33 +00:00
up_write(&nilfs->ns_writer_sem);
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
}
nilfs2: simplify remaining sget() use This simplifies the test function passed on the remaining sget() callsite in nilfs. Instead of checking mount type (i.e. ro-mount/rw-mount/snapshot mount) in the test function passed to sget(), this patch first looks up the nilfs_sb_info struct which the given mount type matches, and then acquires the super block instance holding the nilfs_sb_info. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:31 +00:00
static inline void nilfs_put_sbinfo(struct nilfs_sb_info *sbi)
{
nilfs2: fix oopses with doubly mounted snapshots will fix kernel oopses like the following: # mount -t nilfs2 -r -o cp=20 /dev/sdb1 /test1 # mount -t nilfs2 -r -o cp=20 /dev/sdb1 /test2 # umount /test1 # umount /test2 BUG: sleeping function called from invalid context at arch/x86/mm/fault.c:1069 in_atomic(): 0, irqs_disabled(): 1, pid: 3886, name: umount.nilfs2 1 lock held by umount.nilfs2/3886: #0: (&type->s_umount_key#31){+.+...}, at: [<c10b398a>] deactivate_super+0x52/0x6c irq event stamp: 1219 hardirqs last enabled at (1219): [<c135c774>] __mutex_unlock_slowpath+0xf8/0x119 hardirqs last disabled at (1218): [<c135c6d5>] __mutex_unlock_slowpath+0x59/0x119 softirqs last enabled at (1214): [<c1033316>] __do_softirq+0x1a5/0x1ad softirqs last disabled at (1205): [<c1033354>] do_softirq+0x36/0x5a Pid: 3886, comm: umount.nilfs2 Not tainted 2.6.31-rc6 #55 Call Trace: [<c1023549>] __might_sleep+0x107/0x10e [<c13603c0>] do_page_fault+0x246/0x397 [<c136017a>] ? do_page_fault+0x0/0x397 [<c135e753>] error_code+0x6b/0x70 [<c136017a>] ? do_page_fault+0x0/0x397 [<c104f805>] ? __lock_acquire+0x91/0x12fd [<c1050a62>] ? __lock_acquire+0x12ee/0x12fd [<c1050a62>] ? __lock_acquire+0x12ee/0x12fd [<c1050b2b>] lock_acquire+0xba/0xdd [<d0d17d3f>] ? nilfs_detach_segment_constructor+0x2f/0x2fa [nilfs2] [<c135d4fe>] down_write+0x2a/0x46 [<d0d17d3f>] ? nilfs_detach_segment_constructor+0x2f/0x2fa [nilfs2] [<d0d17d3f>] nilfs_detach_segment_constructor+0x2f/0x2fa [nilfs2] [<c104ea2c>] ? mark_held_locks+0x43/0x5b [<c104ecb1>] ? trace_hardirqs_on_caller+0x10b/0x133 [<c104ece4>] ? trace_hardirqs_on+0xb/0xd [<d0d09ac1>] nilfs_put_super+0x2f/0xca [nilfs2] [<c10b3352>] generic_shutdown_super+0x49/0xb8 [<c10b33de>] kill_block_super+0x1d/0x31 [<c10e6599>] ? vfs_quota_off+0x0/0x12 [<c10b398f>] deactivate_super+0x57/0x6c [<c10c4bc3>] mntput_no_expire+0x8c/0xb4 [<c10c5094>] sys_umount+0x27f/0x2a4 [<c10c50c6>] sys_oldumount+0xd/0xf [<c10031a4>] sysenter_do_call+0x12/0x38 ... This turns out to be a bug brought by an -rc1 patch ("nilfs2: simplify remaining sget() use"). In the patch, a new "put resource" function, nilfs_put_sbinfo() was introduced to delay freeing nilfs_sb_info struct. But the nilfs_put_sbinfo() mistakenly used atomic_dec_and_test() function to check the reference count, and it caused the nilfs_sb_info was freed when user mounted a snapshot twice. This bug also suggests there was unseen memory leak in usual mount /umount operations for nilfs. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-08-18 15:29:43 +00:00
if (atomic_dec_and_test(&sbi->s_count))
nilfs2: simplify remaining sget() use This simplifies the test function passed on the remaining sget() callsite in nilfs. Instead of checking mount type (i.e. ro-mount/rw-mount/snapshot mount) in the test function passed to sget(), this patch first looks up the nilfs_sb_info struct which the given mount type matches, and then acquires the super block instance holding the nilfs_sb_info. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-07 16:39:31 +00:00
kfree(sbi);
}
nilfs2: add helper to get if volume is in a valid state This adds a helper function, nilfs_valid_fs() which returns if nilfs is in a valid state or not. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-19 10:58:46 +00:00
static inline int nilfs_valid_fs(struct the_nilfs *nilfs)
{
unsigned valid_fs;
down_read(&nilfs->ns_sem);
valid_fs = (nilfs->ns_mount_state & NILFS_VALID_FS);
up_read(&nilfs->ns_sem);
return valid_fs;
}
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
static inline void
nilfs_get_segment_range(struct the_nilfs *nilfs, __u64 segnum,
sector_t *seg_start, sector_t *seg_end)
{
*seg_start = (sector_t)nilfs->ns_blocks_per_segment * segnum;
*seg_end = *seg_start + nilfs->ns_blocks_per_segment - 1;
if (segnum == 0)
*seg_start = nilfs->ns_first_data_block;
}
static inline sector_t
nilfs_get_segment_start_blocknr(struct the_nilfs *nilfs, __u64 segnum)
{
return (segnum == 0) ? nilfs->ns_first_data_block :
(sector_t)nilfs->ns_blocks_per_segment * segnum;
}
static inline __u64
nilfs_get_segnum_of_block(struct the_nilfs *nilfs, sector_t blocknr)
{
sector_t segnum = blocknr;
sector_div(segnum, nilfs->ns_blocks_per_segment);
return segnum;
}
static inline void
nilfs_terminate_segment(struct the_nilfs *nilfs, sector_t seg_start,
sector_t seg_end)
{
/* terminate the current full segment (used in case of I/O-error) */
nilfs->ns_pseg_offset = seg_end - seg_start + 1;
}
static inline void nilfs_shift_to_next_segment(struct the_nilfs *nilfs)
{
/* move forward with a full segment */
nilfs->ns_segnum = nilfs->ns_nextnum;
nilfs->ns_pseg_offset = 0;
nilfs->ns_seg_seq++;
}
static inline __u64 nilfs_last_cno(struct the_nilfs *nilfs)
{
__u64 cno;
spin_lock(&nilfs->ns_last_segment_lock);
cno = nilfs->ns_last_cno;
spin_unlock(&nilfs->ns_last_segment_lock);
return cno;
}
nilfs2: simplify handling of active state of segments will reduce some lines of segment constructor. Previously, the state was complexly controlled through a list of segments in order to keep consistency in meta data of usage state of segments. Instead, this presents ``calculated'' active flags to userland cleaner program and stop maintaining its real flag on disk. Only by this fake flag, the cleaner cannot exactly know if each segment is reclaimable or not. However, the recent extension of nilfs_sustat ioctl struct (nilfs2-extend-nilfs_sustat-ioctl-struct.patch) can prevent the cleaner from reclaiming in-use segment wrongly. So, now I can apply this for simplification. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:58 +00:00
static inline int nilfs_segment_is_active(struct the_nilfs *nilfs, __u64 n)
{
return n == nilfs->ns_segnum || n == nilfs->ns_nextnum;
}
nilfs2: add inode and other major structures This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 02:01:23 +00:00
#endif /* _THE_NILFS_H */
Reference in New Issue Copy Permalink