kernel.git/fs/nilfs2, branch linux-2.6.37.y

nilfs2: fix regression that i-flag is not set on changeless checkpoints

2011-03-07T23:05:25Z

commit 72746ac643928f6c3113b5aa783d8ea1b13949d2 upstream. According to the report from Jiro SEKIBA titled "regression in 2.6.37?" (Message-Id: <8739n8vs1f.wl%jir@sekiba.com>), on 2.6.37 and later kernels, lscp command no longer displays "i" flag on checkpoints that snapshot operations or garbage collection created. This is a regression of nilfs2 checkpointing function, and it's critical since it broke behavior of a part of nilfs2 applications. For instance, snapshot manager of TimeBrowse gets to create meaningless snapshots continuously; snapshot creation triggers another checkpoint, but applications cannot distinguish whether the new checkpoint contains meaningful changes or not without the i-flag. This patch fixes the regression and brings that application behavior back to normal. Reported-by: Jiro SEKIBA Signed-off-by: Ryusuke Konishi Tested-by: Ryusuke Konishi Tested-by: Jiro SEKIBA Signed-off-by: Greg Kroah-Hartman

mm: prevent concurrent unmap_mapping_range() on the same inode

2011-03-07T23:05:08Z

commit 2aa15890f3c191326678f1bd68af61ec6b8753ec upstream. Michael Leun reported that running parallel opens on a fuse filesystem can trigger a "kernel BUG at mm/truncate.c:475" Gurudas Pai reported the same bug on NFS. The reason is, unmap_mapping_range() is not prepared for more than one concurrent invocation per inode. For example: thread1: going through a big range, stops in the middle of a vma and stores the restart address in vm_truncate_count. thread2: comes in with a small (e.g. single page) unmap request on the same vma, somewhere before restart_address, finds that the vma was already unmapped up to the restart address and happily returns without doing anything. Another scenario would be two big unmap requests, both having to restart the unmapping and each one setting vm_truncate_count to its own value. This could go on forever without any of them being able to finish. Truncate and hole punching already serialize with i_mutex. Other callers of unmap_mapping_range() do not, and it's difficult to get i_mutex protection for all callers. In particular ->d_revalidate(), which calls invalidate_inode_pages2_range() in fuse, may be called with or without i_mutex. This patch adds a new mutex to 'struct address_space' to prevent running multiple concurrent unmap_mapping_range() on the same mapping. [ We'll hopefully get rid of all this with the upcoming mm preemptibility series by Peter Zijlstra, the "mm: Remove i_mmap_mutex lockbreak" patch in particular. But that is for 2.6.39 ] Signed-off-by: Miklos Szeredi Reported-by: Michael Leun Reported-by: Gurudas Pai Tested-by: Gurudas Pai Acked-by: Hugh Dickins Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

nilfs2: fix crash after one superblock became unavailable

2011-02-17T23:14:59Z

commit 0ca7a5b9ac5d301845dd6382ff25a699b6263a81 upstream. Fixes the following kernel oops in nilfs_setup_super() which could arise if one of two super-blocks is unavailable. > BUG: unable to handle kernel NULL pointer dereference at (null) > Pid: 3529, comm: mount.nilfs2 Not tainted 2.6.37 #1 / > EIP: 0060:[] EFLAGS: 00010202 CPU: 3 > EIP is at memcpy+0xc/0x1b > Call Trace: > [] ? nilfs_setup_super+0x6c/0xa5 [nilfs2] > [] ? nilfs_get_root_dentry+0x81/0xcb [nilfs2] > [] ? nilfs_mount+0x4f9/0x62c [nilfs2] > [] ? kstrdup+0x36/0x3f > [] ? nilfs_mount+0x0/0x62c [nilfs2] > [] ? vfs_kern_mount+0x4d/0x12c > [] ? get_fs_type+0x76/0x8f > [] ? do_kern_mount+0x33/0xbf > [] ? do_mount+0x2ed/0x714 > [] ? copy_mount_options+0x28/0xfc > [] ? sys_mount+0x72/0xaf > [] ? syscall_call+0x7/0xb Reported-by: Wakko Warner Signed-off-by: Ryusuke Konishi Tested-by: Wakko Warner LKML-Reference: <20110121024918.GA29598@animx.eu.org> Signed-off-by: Greg Kroah-Hartman

nilfs2: fix regression of garbage collection ioctl

2010-12-16T05:35:18Z

On 2.6.37-rc1, garbage collection ioctl of nilfs was broken due to the commit 263d90cefc7d82a0 ("nilfs2: remove own inode hash used for GC"), and leading to filesystem corruption. The patch doesn't queue gc-inodes for log writer if they are reused through the vfs inode cache. Here, gc-inode is the inode which buffers blocks to be relocated on GC. That patch queues gc-inodes in nilfs_init_gcinode() function, but this function is not called when they don't have I_NEW flag. Thus, some of live blocks are wrongly overrode without being moved to new logs. This resolves the problem by moving the gc-inode queueing to an outer function to ensure it's done right. Signed-off-by: Ryusuke Konishi

nilfs2: fix typo in comment of nilfs_dat_move function

2010-11-24T03:51:48Z

Fixes a typo: "uncommited" -> "uncommitted". Signed-off-by: Ryusuke Konishi

nilfs2: nilfs_iget_for_gc() returns ERR_PTR

2010-11-23T07:32:19Z

nilfs_iget_for_gc() returns an ERR_PTR() on failure and doesn't return NULL. Signed-off-by: Dan Carpenter Signed-off-by: Ryusuke Konishi

convert nilfs

2010-10-29T08:16:53Z

Signed-off-by: Al Viro

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2010-10-27T00:58:44Z

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits) split invalidate_inodes() fs: skip I_FREEING inodes in writeback_sb_inodes fs: fold invalidate_list into invalidate_inodes fs: do not drop inode_lock in dispose_list fs: inode split IO and LRU lists fs: switch bdev inode bdi's correctly fs: fix buffer invalidation in invalidate_list fsnotify: use dget_parent smbfs: use dget_parent exportfs: use dget_parent fs: use RCU read side protection in d_validate fs: clean up dentry lru modification fs: split __shrink_dcache_sb fs: improve DCACHE_REFERENCED usage fs: use percpu counter for nr_dentry and nr_dentry_unused fs: simplify __d_free fs: take dcache_lock inside __d_path fs: do not assign default i_ino in new_inode fs: introduce a per-cpu last_ino allocator new helper: ihold() ...

mm: add account_page_writeback()

2010-10-26T23:52:06Z

To help developers and applications gain visibility into writeback behaviour this patch adds two counters to /proc/vmstat. # grep nr_dirtied /proc/vmstat nr_dirtied 3747 # grep nr_written /proc/vmstat nr_written 3618 These entries allow user apps to understand writeback behaviour over time and learn how it is impacting their performance. Currently there is no way to inspect dirty and writeback speed over time. It's not possible for nr_dirty/nr_writeback. These entries are necessary to give visibility into writeback behaviour. We have /proc/diskstats which lets us understand the io in the block layer. We have blktrace for more in depth understanding. We have e2fsprogs and debugsfs to give insight into the file systems behaviour, but we don't offer our users the ability understand what writeback is doing. There is no way to know how active it is over the whole system, if it's falling behind or to quantify it's efforts. With these values exported users can easily see how much data applications are sending through writeback and also at what rates writeback is processing this data. Comparing the rates of change between the two allow developers to see when writeback is not able to keep up with incoming traffic and the rate of dirty memory being sent to the IO back end. This allows folks to understand their io workloads and track kernel issues. Non kernel engineers at Google often use these counters to solve puzzling performance problems. Patch #4 adds a pernode vmstat file with nr_dirtied and nr_written Patch #5 add writeback thresholds to /proc/vmstat Currently these values are in debugfs. But they should be promoted to /proc since they are useful for developers who are writing databases and file servers and are not debugging the kernel. The output is as below: # grep threshold /proc/vmstat nr_pages_dirty_threshold 409111 nr_pages_dirty_background_threshold 818223 This patch: This allows code outside of the mm core to safely manipulate page writeback state and not worry about the other accounting. Not using these routines means that some code will lose track of the accounting and we get bugs. Modify nilfs2 to use interface. Signed-off-by: Michael Rubin Reviewed-by: KOSAKI Motohiro Reviewed-by: Wu Fengguang Cc: KONISHI Ryusuke Cc: Jiro SEKIBA Cc: Dave Chinner Cc: Jens Axboe Cc: KOSAKI Motohiro Cc: Nick Piggin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

new helper: ihold()

2010-10-26T01:26:11Z

Clones an existing reference to inode; caller must already hold one. Signed-off-by: Al Viro