linux-stable.git/fs/logfs/dir.c, branch linux-3.3.y

Merge tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream

2012-01-31T17:23:59+00:00

There are few important bug fixes for LogFS

* tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream:
  Logfs: Allow NULL block_isbad() methods
  logfs: Grow inode in delete path
  logfs: Free areas before calling generic_shutdown_super()
  logfs: remove useless BUG_ON
  MAINTAINERS: Add Prasad Joshi in LogFS maintiners
  logfs: Propagate page parameter to __logfs_write_inode
  logfs: set superblock shutdown flag after generic sb shutdown
  logfs: take write mutex lock during fsync and sync
  logfs: Prevent memory corruption
  logfs: update page reference count for pined pages

Fix up conflict in fs/logfs/dev_mtd.c due to semantic change in what
"mtd->block_isbad" means in commit f2933e86ad93: "Logfs: Allow NULL
block_isbad() methods" clashing with the abstraction changes in the
commits 7086c19d0742: "mtd: introduce mtd_block_isbad interface" and
d58b27ed58a3: "logfs: do not use 'mtd->block_isbad' directly".

This resolution takes the semantics from commit f2933e86ad93, and just
makes mtd_block_isbad() return zero (false) if the 'block_isbad'
function is NULL.  But that also means that now "mtd_can_have_bb()"
always returns 0.

Now, "mtd_block_markbad()" will obviously return an error if the
low-level driver doesn't support bad blocks, so this is somewhat
non-symmetric, but it actually makes sense if a NULL "block_isbad"
function is considered to mean "I assume that all my blocks are always
good".

logfs: Propagate page parameter to __logfs_write_inode

2012-01-28T06:08:25+00:00

During GC LogFS has to rewrite each valid block to a separate segment.
Rewrite operation reads data from an old segment and writes it to a
newly allocated segment. Since every write operation changes data
block pointers maintained in inode, inode should also be rewritten.

In GC path to avoid AB-BA deadlock LogFS marks a page with
PG_pre_locked in addition to locking the page (PG_locked). The page
lock is ignored iff the page is pre-locked.

LogFS uses a special file called segment file. The segment file
maintains an 8 bytes entry for every segment. It keeps track of erase
count, level etc. for every segment.

Bad things happen with a segment belonging to the segment file is GCed

 ------------[ cut here ]------------
kernel BUG at /home/prasad/logfs/readwrite.c:297!
invalid opcode: 0000 [#1] SMP
Modules linked in: logfs joydev usbhid hid psmouse e1000 i2c_piix4
		serio_raw [last unloaded: logfs]
Pid: 20161, comm: mount Not tainted 3.1.0-rc3+ #3 innotek GmbH
		VirtualBox
EIP: 0060:[] EFLAGS: 00010292 CPU: 0
EIP is at logfs_lock_write_page+0x6a/0x70 [logfs]
EAX: 00000027 EBX: f73f5b20 ECX: c16007c8 EDX: 00000094
ESI: 00000000 EDI: e59be6e4 EBP: c7337b28 ESP: c7337b18
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process mount (pid: 20161, ti=c7336000 task=eb323f70 task.ti=c7336000)
Stack:
f8099a3d c7337b24 f73f5b20 00001002 c7337b50 f8091f6d f8099a4d f80994e4
00000003 00000000 c7337b68 00000000 c67e4400 00001000 c7337b80 f80935e5
00000000 00000000 00000000 00000000 e1fcf000 0000000f e59be618 c70bf900
Call Trace:
[] logfs_get_write_page.clone.16+0xdd/0x100 [logfs]
[] logfs_mod_segment_entry+0x55/0x110 [logfs]
[] logfs_get_segment_entry+0x1d/0x20 [logfs]
[] ? logfs_cleanup_journal+0x50/0x50 [logfs]
[] ostore_get_erase_count+0x1b/0x40 [logfs]
[] logfs_open_area+0xc8/0x150 [logfs]
[] ? kmemleak_alloc+0x2c/0x60
[] __logfs_segment_write.clone.16+0x4e/0x1b0 [logfs]
[] ? mempool_kmalloc+0x13/0x20
[] ? mempool_kmalloc+0x13/0x20
[] logfs_segment_write+0x17f/0x1d0 [logfs]
[] logfs_write_i0+0x11c/0x180 [logfs]
[] logfs_write_direct+0x45/0x90 [logfs]
[] __logfs_write_buf+0xbd/0xf0 [logfs]
[] ? kmap_atomic_prot+0x4e/0xe0
[] logfs_write_buf+0x3b/0x60 [logfs]
[] __logfs_write_inode+0xa9/0x110 [logfs]
[] logfs_rewrite_block+0xc0/0x110 [logfs]
[] ? get_mapping_page+0x10/0x60 [logfs]
[] ? logfs_load_object_aliases+0x2e0/0x2f0 [logfs]
[] logfs_gc_segment+0x2ad/0x310 [logfs]
[] __logfs_gc_once+0x4a/0x80 [logfs]
[] logfs_gc_pass+0x683/0x6a0 [logfs]
[] logfs_mount+0x5a9/0x680 [logfs]
[] mount_fs+0x21/0xd0
[] ? __alloc_percpu+0xf/0x20
[] ? alloc_vfsmnt+0xb1/0x130
[] vfs_kern_mount+0x4b/0xa0
[] do_kern_mount+0x3e/0xe0
[] do_mount+0x34d/0x670
[] ? strndup_user+0x49/0x70
[] sys_mount+0x6b/0xa0
[] syscall_call+0x7/0xb
Code: f8 e8 8b 93 39 c9 8b 45 f8 3e 0f ba 28 00 19 d2 85 d2 74 ca eb d0 0f 0b 8d 45 fc 89 44 24 04 c7 04 24 3d 9a 09 f8 e8 09 92 39 c9 <0f> 0b 8d 74 26 00 55 89 e5 3e 8d 74 26 00 8b 10 80 e6 01 74 09
EIP: [] logfs_lock_write_page+0x6a/0x70 [logfs] SS:ESP 0068:c7337b18
---[ end trace 96e67d5b3aa3d6ca ]---

The patch passes locked page to __logfs_write_inode. It calls function
logfs_get_wblocks() to pre-lock the page. This ensures any further
attempts to lock the page are ignored (esp from get_erase_count).

Acked-by: Joern Engel 
Signed-off-by: Prasad Joshi

switch ->mknod() to umode_t

2012-01-04T03:54:54+00:00

Signed-off-by: Al Viro

switch ->create() to umode_t

2012-01-04T03:54:53+00:00

vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method

Signed-off-by: Al Viro

switch vfs_mkdir() and ->mkdir() to umode_t

2012-01-04T03:54:53+00:00

vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...

Signed-off-by: Al Viro

filesystems: add missing nlink wrappers

2011-11-02T11:53:43+00:00

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

make d_splice_alias(ERR_PTR(err), dentry) = ERR_PTR(err)

2011-07-20T05:44:26+00:00

... and simplify the living hell out of callers

Signed-off-by: Al Viro

logfs doesn't need ->permission() at all

2011-06-20T14:44:26+00:00

... and never did, what with its ->permission() being what we do by default
when ->permission is NULL...

Signed-off-by: Al Viro

logfs: remove unnecessary dentry_unhash from rmdir, dir rename

2011-05-28T05:02:51+00:00

logfs does not have problems with references to unlinked directories.

CC: Joern Engel 
CC: logfs@logfs.org
Signed-off-by: Sage Weil 
Signed-off-by: Al Viro

vfs: push dentry_unhash on rename_dir into file systems

2011-05-26T11:26:48+00:00

Only a few file systems need this.  Start by pushing it down into each
rename method (except gfs2 and xfs) so that it can be dealt with on a
per-fs basis.

Acked-by: Christoph Hellwig 
Signed-off-by: Sage Weil 
Signed-off-by: Al Viro