First of all some necessary notes about UFS by it self: To avoid waste of disk
space the tail of file consists not from blocks (which is ordinary big enough,
16K usually), it consists from fragments(which is ordinary 2K).  When file is
growing its tail occupy 1 fragment, 2 fragments...  At some stage decision to
allocate whole block is made and all fragments are moved to one block.

How this situation was handled before:

  ufs_prepare_write
  ->block_prepare_write
    ->ufs_getfrag_block
      ->...
        ->ufs_new_fragments:

	bh = sb_bread
	bh->b_blocknr = result + i;
	mark_buffer_dirty (bh);

This is wrong solution, because:

- it didn't take into consideration that there is another cache: "inode page
  cache"

- because of sb_getblk uses not b_blocknr, (it uses page->index) to find
  certain block, this breaks sb_getblk.

How this situation is handled now: we go though all "page inode cache", if
there are no such page in cache we load it into cache, and change b_blocknr.
Signed-off-by: NEvgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

* After block allocation, we map it on the same "address" as 8 others
  blocks

* We nullify block several times: once in ufs/block.c and once in
  block_*write_full_page, and use different "caches" for this.
Signed-off-by: NEvgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This fixes the code like this:

	bh = sb_find_get_block (sb, tmp + j);
	if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *p)) {
		retry = 1;
		brelse (bh);
		goto next1;
	}
	bforget (bh);

sb_find_get_block() ordinarily returns a buffer_head with b_count>=2, and
this code assume that in case if "b_count>1" buffer is used, so this caused
infinite loop.

(akpm: that is-the-buffer-busy code is incomprehensible.  Good riddance.  Use
of block_truncate_page() seems sane).
Signed-off-by: NEvgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Here is update of ufs cleanup patch, brought on by the recently fixed
ubh_get_usb_second() bug that made some ugly code rather painfully
obvious.  It also includes

 - fix compilation warnings which appears if debug mode turn on
 - remove unnecessary duplication of code to support UFS2

I tested it on ufs1 and ufs2 file-systems.
Signed-off-by: NEvgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Update the file systems in fs/ implementing a delete_inode() callback to
call truncate_inode_pages().  One implementation note: In developing this
patch I put the calls to truncate_inode_pages() at the very top of those
filesystems delete_inode() callbacks in order to retain the previous
behavior.  I'm guessing that some of those could probably be optimized.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>
Acked-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!