BMC/Intel-BMC/linux.git/fs/ocfs2/file.h, branch dev

ocfs2: prepare some interfaces used in append direct io

2015-02-17T01:56:04+00:00

Currently in case of append O_DIRECT write (block not allocated yet), ocfs2 will fall back to buffered I/O. This has some disadvantages. Firstly, it is not the behavior as expected. Secondly, it will consume huge page cache, e.g. in mass backup scenario. Thirdly, modern filesystems such as ext4 support this feature. In this patch set, the direct I/O write doesn't fallback to buffer I/O write any more because the allocate blocks are enabled in direct I/O now. This patch (of 9): Prepare some interfaces which will be used in append O_DIRECT write. Signed-off-by: Joseph Qi Cc: Weiwei Wang Cc: Mark Fasheh Cc: Joel Becker Cc: Xuejiufei Cc: Junxiao Bi Cc: alex chen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

->permission() sanitizing: don't pass flags to ->permission()

2011-07-20T05:43:24+00:00

not used by the instances anymore. Signed-off-by: Al Viro

fs: provide rcu-walk aware permission i_ops

2011-01-07T06:50:29+00:00

Signed-off-by: Nick Piggin

ocfs2: Zero the tail cluster when extending past i_size.

2010-07-08T20:25:35+00:00

ocfs2's allocation unit is the cluster. This can be larger than a block or even a memory page. This means that a file may have many blocks in its last extent that are beyond the block containing i_size. There also may be more unwritten extents after that. When ocfs2 grows a file, it zeros the entire cluster in order to ensure future i_size growth will see cleared blocks. Unfortunately, block_write_full_page() drops the pages past i_size. This means that ocfs2 is actually leaking garbage data into the tail end of that last cluster. This is a bug. We adjust ocfs2_write_begin_nolock() and ocfs2_extend_file() to detect when a write or truncate is past i_size. They will use ocfs2_zero_extend() to ensure the data is properly zeroed. Older versions of ocfs2_zero_extend() simply zeroed every block between i_size and the zeroing position. This presumes three things: 1) There is allocation for all of these blocks. 2) The extents are not unwritten. 3) The extents are not refcounted. (1) and (2) hold true for non-sparse filesystems, which used to be the only users of ocfs2_zero_extend(). (3) is another bug. Since we're now using ocfs2_zero_extend() for sparse filesystems as well, we teach ocfs2_zero_extend() to check every extent between i_size and the zeroing position. If the extent is unwritten, it is ignored. If it is refcounted, it is CoWed. Then it is zeroed. Signed-off-by: Joel Becker Cc: stable@kernel.org

ocfs2: Integrate CoW in file write.

2009-09-23T03:09:37+00:00

When we use mmap, we CoW the refcountd clusters in ocfs2_write_begin_nolock. While for normal file io(including directio), we do CoW in ocfs2_prepare_inode_for_write. Signed-off-by: Tao Ma

ocfs2: Implementation of local and global quota file handling

2009-01-05T16:40:23+00:00

For each quota type each node has local quota file. In this file it stores changes users have made to disk usage via this node. Once in a while this information is synced to global file (and thus with other nodes) so that limits enforcement at least aproximately works. Global quota files contain all the information about usage and limits. It's mostly handled by the generic VFS code (which implements a trie of structures inside a quota file). We only have to provide functions to convert structures from on-disk format to in-memory one. We also have to provide wrappers for various quota functions starting transactions and acquiring necessary cluster locks before the actual IO is really started. Signed-off-by: Jan Kara Signed-off-by: Mark Fasheh

ocfs2: Make high level btree extend code generic

2008-10-13T20:57:59+00:00

Factor out the non-inode specifics of ocfs2_do_extend_allocation() into a more generic function, ocfs2_do_cluster_allocation(). ocfs2_do_extend_allocation calls ocfs2_do_cluster_allocation() now, but the latter can be used for other btree types as well. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: Abstract ocfs2_extent_tree in b-tree operations.

2008-10-13T20:57:58+00:00

In the old extent tree operation, we take the hypothesis that we are using the ocfs2_extent_list in ocfs2_dinode as the tree root. As xattr will also use ocfs2_extent_list to store large value for a xattr entry, we refactor the tree operation so that xattr can use it directly. The refactoring includes 4 steps: 1. Abstract set/get of last_eb_blk and update_clusters since they may be stored in different location for dinode and xattr. 2. Add a new structure named ocfs2_extent_tree to indicate the extent tree the operation will work on. 3. Remove all the use of fe_bh and di, use root_bh and root_el in extent tree instead. So now all the fe_bh is replaced with et->root_bh, el with root_el accordingly. 4. Make ocfs2_lock_allocators generic. Now it is limited to be only used in file extend allocation. But the whole function is useful when we want to store large EAs. Note: This patch doesn't touch ocfs2_commit_truncate() since it is not used for anything other than truncate inode data btrees. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: Modify ocfs2_num_free_extents for future xattr usage.

2008-10-13T20:57:58+00:00

ocfs2_num_free_extents() is used to find the number of free extent records in an inode btree. Hence, it takes an "ocfs2_dinode" parameter. We want to use this for extended attribute trees in the future, so genericize the interface the take a buffer head. A future patch will allow that buffer_head to contain any structure rooting an ocfs2 btree. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: POSIX file locks support

2008-10-13T20:57:57+00:00

This is actually pretty easy since fs/dlm already handles the bulk of the work. The Ocfs2 userspace cluster stack module already uses fs/dlm as the underlying lock manager, so I only had to add the right calls. Cluster-aware POSIX locks ("plocks") can be turned off by the same means at UNIX locks - mount with 'noflocks', or create a local-only Ocfs2 volume. Internally, the file system uses two sets of file_operations, depending on whether cluster aware plocks is required. This turns out to be easier than implementing local-only versions of ->lock. Signed-off-by: Mark Fasheh