linux-toradex.git/fs/nilfs2/segment.c, branch v3.2.39

nilfs2: ensure proper cache clearing for gc-inodes

2012-07-04T04:44:10+00:00

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 problem in setting checkpoint interval

2011-06-11T06:51:15+00:00

Checkpoint generation interval of nilfs goes wrong after user has
changed the interval parameter with nilfs-tune tool.

 segctord starting. Construction interval = 5 seconds,
 CP frequency < 30 seconds
 segctord starting. Construction interval = 0 seconds,
 CP frequency < 30 seconds

This turned out to be caused by a trivial bug in initialization code
of log writer.  This will fix it.

Reported-by: Andrea Gelmini 
Signed-off-by: Ryusuke Konishi

nilfs2: use mark_buffer_dirty to mark btnode or meta data dirty

2011-05-10T13:21:57+00:00

This replaces nilfs_mdt_mark_buffer_dirty and nilfs_btnode_mark_dirty
macros with mark_buffer_dirty and gets rid of nilfs_mark_buffer_dirty,
an own mark buffer dirty function.

Signed-off-by: Ryusuke Konishi

nilfs2: always set back pointer to host inode in mapping->host

2011-05-10T13:21:57+00:00

In the current nilfs, page cache for btree nodes and meta data files
do not set a valid back pointer to the host inode in mapping->host.

This will change it so that every address space in nilfs uses
mapping->host to hold its host inode.

Signed-off-by: Ryusuke Konishi

nilfs2: use list_first_entry

2011-05-10T13:21:56+00:00

This uses list_first_entry macro instead of list_entry if it's used to
get the first entry.

Signed-off-by: Ryusuke Konishi

nilfs2: zero fill unused portion of super root block

2011-05-10T13:21:45+00:00

The super root block is newly-allocated each time it is written back
to disk, so unused portion of the block should be cleared.

Signed-off-by: Ryusuke Konishi

nilfs2: super root size should change depending on inode size

2011-05-10T13:21:44+00:00

The size of super root structure depends on inode size, so
NILFS_SR_BYTES macro should be a function of the inode size.  This
fixes the issue.

Even though a different size value will be written for a possible
future filesystem with extended inode, but fortunately this does not
break disk format compatibility.

Signed-off-by: Ryusuke Konishi

nilfs2: get rid of private page allocator

2011-05-10T13:21:44+00:00

Previously, nilfs was cloning pages for mmapped region to freeze their
data and ensure consistency of checksum during writeback cycles.  A
private page allocator was used for this page cloning.  But, we no
longer need to do that since clear_page_dirty_for_io function sets up
pte so that vm_ops->page_mkwrite function is called right before the
mmapped pages are modified and nilfs_page_mkwrite function can safely
wait for the pages to be written back to disk.

So, this stops making a copy of mmapped pages during writeback, and
eliminates the private page allocation and deallocation functions from
nilfs.

Signed-off-by: Ryusuke Konishi

nilfs2: merge list_del()/list_add_tail() to list_move_tail()

2011-05-10T13:21:44+00:00

Merge list_del() + list_add_tail() to list_move_tail().

Signed-off-by: Nicolas Kaiser 
Signed-off-by: Ryusuke Konishi

nilfs2: get rid of nilfs_sb_info structure

2011-03-09T02:54:26+00:00

This directly uses sb->s_fs_info to keep a nilfs filesystem object and
fully removes the intermediate nilfs_sb_info structure.  With this
change, the hierarchy of on-memory structures of nilfs will be
simplified as follows:

Before:
  super_block
       -> nilfs_sb_info
             -> the_nilfs
                   -> cptree --+-> nilfs_root (current file system)
                               +-> nilfs_root (snapshot A)
                               +-> nilfs_root (snapshot B)
                               :
             -> nilfs_sc_info (log writer structure)
After:
  super_block
       -> the_nilfs
             -> cptree --+-> nilfs_root (current file system)
                         +-> nilfs_root (snapshot A)
                         +-> nilfs_root (snapshot B)
                         :
             -> nilfs_sc_info (log writer structure)

The reason why we didn't design so from the beginning is because the
initial shape also differed from the above.  The early hierachy was
composed of "per-mount-point" super_block -> nilfs_sb_info pairs and a
shared nilfs object.  On the kernel 2.6.37, it was changed to the
current shape in order to unify super block instances into one per
device, and this cleanup became applicable as the result.

Signed-off-by: Ryusuke Konishi