linux/fs/nilfs2, branch v3.2.40

nilfs2: fix fix very long mount time issue

2013-02-20T03:15:25Z

commit a9bae189542e71f91e61a4428adf6e5a7dfe8063 upstream. There exists a situation when GC can work in background alone without any other filesystem activity during significant time. The nilfs_clean_segments() method calls nilfs_segctor_construct() that updates superblocks in the case of NILFS_SC_SUPER_ROOT and THE_NILFS_DISCONTINUED flags are set. But when GC is working alone the nilfs_clean_segments() is called with unset THE_NILFS_DISCONTINUED flag. As a result, the update of superblocks doesn't occurred all this time and in the case of SPOR superblocks keep very old values of last super root placement. SYMPTOMS: Trying to mount a NILFS2 volume after SPOR in such environment ends with very long mounting time (it can achieve about several hours in some cases). REPRODUCING PATH: 1. It needs to use external USB HDD, disable automount and doesn't make any additional filesystem activity on the NILFS2 volume. 2. Generate temporary file with size about 100 - 500 GB (for example, dd if=/dev/zero of= bs=1073741824 count=200). The size of file defines duration of GC working. 3. Then it needs to delete file. 4. Start GC manually by means of command "nilfs-clean -p 0". When you start GC by means of such way then, at the end, superblocks is updated by once. So, for simulation of SPOR, it needs to wait sometime (15 - 40 minutes) and simply switch off USB HDD manually. 5. Switch on USB HDD again and try to mount NILFS2 volume. As a result, NILFS2 volume will mount during very long time. REPRODUCIBILITY: 100% FIX: This patch adds checking that superblocks need to update and set THE_NILFS_DISCONTINUED flag before nilfs_clean_segments() call. Reported-by: Sergey Alexandrov Signed-off-by: Vyacheslav Dubeyko Tested-by: Vyacheslav Dubeyko Acked-by: Ryusuke Konishi Tested-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

nilfs2: fix deadlock issue between chcp and thaw ioctls

2012-08-09T23:25:02Z

commit 572d8b3945a31bee7c40d21556803e4807fd9141 upstream. An fs-thaw ioctl causes deadlock with a chcp or mkcp -s command: chcp D ffff88013870f3d0 0 1325 1324 0x00000004 ... Call Trace: nilfs_transaction_begin+0x11c/0x1a0 [nilfs2] wake_up_bit+0x20/0x20 copy_from_user+0x18/0x30 [nilfs2] nilfs_ioctl_change_cpmode+0x7d/0xcf [nilfs2] nilfs_ioctl+0x252/0x61a [nilfs2] do_page_fault+0x311/0x34c get_unmapped_area+0x132/0x14e do_vfs_ioctl+0x44b/0x490 __set_task_blocked+0x5a/0x61 vm_mmap_pgoff+0x76/0x87 __set_current_blocked+0x30/0x4a sys_ioctl+0x4b/0x6f system_call_fastpath+0x16/0x1b thaw D ffff88013870d890 0 1352 1351 0x00000004 ... Call Trace: rwsem_down_failed_common+0xdb/0x10f call_rwsem_down_write_failed+0x13/0x20 down_write+0x25/0x27 thaw_super+0x13/0x9e do_vfs_ioctl+0x1f5/0x490 vm_mmap_pgoff+0x76/0x87 sys_ioctl+0x4b/0x6f filp_close+0x64/0x6c system_call_fastpath+0x16/0x1b where the thaw ioctl deadlocked at thaw_super() when called while chcp was waiting at nilfs_transaction_begin() called from nilfs_ioctl_change_cpmode(). This deadlock is 100% reproducible. This is because nilfs_ioctl_change_cpmode() first locks sb->s_umount in read mode and then waits for unfreezing in nilfs_transaction_begin(), whereas thaw_super() locks sb->s_umount in write mode. The locking of sb->s_umount here was intended to make snapshot mounts and the downgrade of snapshots to checkpoints exclusive. This fixes the deadlock issue by replacing the sb->s_umount usage in nilfs_ioctl_change_cpmode() with a dedicated mutex which protects snapshot mounts. Signed-off-by: Ryusuke Konishi Cc: Fernando Luis Vazquez Cao Tested-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

nilfs2: ensure proper cache clearing for gc-inodes

2012-07-04T04:44:10Z

commit fbb24a3a915f105016f1c828476be11aceac8504 upstream. A gc-inode is a pseudo inode used to buffer the blocks to be moved by garbage collection. Block caches of gc-inodes must be cleared every time a garbage collection function (nilfs_clean_segments) completes. Otherwise, stale blocks buffered in the caches may be wrongly reused in successive calls of the GC function. For user files, this is not a problem because their gc-inodes are distinguished by a checkpoint number as well as an inode number. They never buffer different blocks if either an inode number, a checkpoint number, or a block offset differs. However, gc-inodes of sufile, cpfile and DAT file can store different data for the same block offset. Thus, the nilfs_clean_segments function can move incorrect block for these meta-data files if an old block is cached. I found this is really causing meta-data corruption in nilfs. This fixes the issue by ensuring cache clear of gc-inodes and resolves reported GC problems including checkpoint file corruption, b-tree corruption, and the following warning during GC. nilfs_palloc_freev: entry number 307234 already freed. ... Signed-off-by: Ryusuke Konishi Tested-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

nilfs2: fix NULL pointer dereference in nilfs_load_super_block()

2012-03-23T18:21:21Z

commit d7178c79d9b7c5518f9943188091a75fc6ce0675 upstream. According to the report from Slicky Devil, nilfs caused kernel oops at nilfs_load_super_block function during mount after he shrank the partition without resizing the filesystem: BUG: unable to handle kernel NULL pointer dereference at 00000048 IP: [] nilfs_load_super_block+0x17e/0x280 [nilfs2] *pde = 00000000 Oops: 0000 [#1] PREEMPT SMP ... Call Trace: [] init_nilfs+0x4b/0x2e0 [nilfs2] [] nilfs_mount+0x447/0x5b0 [nilfs2] [] mount_fs+0x36/0x180 [] vfs_kern_mount+0x51/0xa0 [] do_kern_mount+0x3e/0xe0 [] do_mount+0x169/0x700 [] sys_mount+0x6b/0xa0 [] sysenter_do_call+0x12/0x28 Code: 53 18 8b 43 20 89 4b 18 8b 4b 24 89 53 1c 89 43 24 89 4b 20 8b 43 20 c7 43 2c 00 00 00 00 23 75 e8 8b 50 68 89 53 28 8b 54 b3 20 <8b> 72 48 8b 7a 4c 8b 55 08 89 b3 84 00 00 00 89 bb 88 00 00 00 EIP: [] nilfs_load_super_block+0x17e/0x280 [nilfs2] SS:ESP 0068:ca9bbdcc CR2: 0000000000000048 This turned out due to a defect in an error path which runs if the calculated location of the secondary super block was invalid. This patch fixes it and eliminates the reported oops. Reported-by: Slicky Devil Signed-off-by: Ryusuke Konishi Tested-by: Slicky Devil Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

nilfs2: potential integer overflow in nilfs_ioctl_clean_segments()

2011-12-20T18:25:04Z

There is a potential integer overflow in nilfs_ioctl_clean_segments(). When a large argv[n].v_nmembs is passed from the userspace, the subsequent call to vmalloc() will allocate a buffer smaller than expected, which leads to out-of-bound access in nilfs_ioctl_move_blocks() and lfs_clean_segments(). The following check does not prevent the overflow because nsegs is also controlled by the userspace and could be very large. if (argv[n].v_nmembs > nsegs * nilfs->ns_blocks_per_segment) goto out_free; This patch clamps argv[n].v_nmembs to UINT_MAX / argv[n].v_size, and returns -EINVAL when overflow. Signed-off-by: Haogang Chen Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: unbreak compat ioctl

2011-12-20T18:25:04Z

commit 828b1c50ae ("nilfs2: add compat ioctl") incidentally broke all other NILFS compat ioctls. Make them work again. Signed-off-by: Thomas Meyer Signed-off-by: Ryusuke Konishi Tested-by: Ryusuke Konishi Cc: [3.0+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

filesystems: add set_nlink()

2011-11-02T11:53:43Z

Replace remaining direct i_nlink updates with a new set_nlink() updater function. Signed-off-by: Miklos Szeredi Tested-by: Toshiyuki Okajima Signed-off-by: Christoph Hellwig

filesystems: add missing nlink wrappers

2011-11-02T11:53:43Z

Replace direct i_nlink updates with the respective updater function (inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count). Signed-off-by: Miklos Szeredi

treewide: use printf not attribute__((format(printf,...)))

2011-11-01T00:30:54Z

Standardize the style for compiler based printf format verification. Standardized the location of __printf too. Done via script and a little typing. $ grep -rPl --include=*.[ch] -w "__attribute__" * | \ grep -vP "^(tools|scripts|include/linux/compiler-gcc.h)" | \ xargs perl -n -i -e 'local $/; while (<>) { s/\b__attribute__\s*$\s*\(\s*format\s*\(\s*printf\s*,\s*(.+)\s*,\s*(.+)\s*$\s*\)\s*\)/__printf($1, $2)/g ; print; }' [akpm@linux-foundation.org: revert arch bits] Signed-off-by: Joe Perches Cc: "Kirill A. Shutemov" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers

2011-07-21T00:47:59Z

Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara Signed-off-by: Josef Bacik Signed-off-by: Al Viro