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path: root/fs/xfs/xfs_fs.h
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2007-10-19[XFS] cleanup fid types messChristoph Hellwig
Currently XFs has three different fid types: struct fid, struct xfs_fid and struct xfs_fid2 with hte latter two beeing identicaly and the first one beeing the same size but an unstructured array with the same size. This patch consolidates all this to alway uuse struct xfs_fid. This patch is required for an upcoming patch series from me that revamps the nfs exporting code and introduces a Linux-wide struct fid. SGI-PV: 970336 SGI-Modid: xfs-linux-melb:xfs-kern:29651a Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-07-14[XFS] Concurrent Multi-File Data StreamsDavid Chinner
In media spaces, video is often stored in a frame-per-file format. When dealing with uncompressed realtime HD video streams in this format, it is crucial that files do not get fragmented and that multiple files a placed contiguously on disk. When multiple streams are being ingested and played out at the same time, it is critical that the filesystem does not cross the streams and interleave them together as this creates seek and readahead cache miss latency and prevents both ingest and playout from meeting frame rate targets. This patch set creates a "stream of files" concept into the allocator to place all the data from a single stream contiguously on disk so that RAID array readahead can be used effectively. Each additional stream gets placed in different allocation groups within the filesystem, thereby ensuring that we don't cross any streams. When an AG fills up, we select a new AG for the stream that is not in use. The core of the functionality is the stream tracking - each inode that we create in a directory needs to be associated with the directories' stream. Hence every time we create a file, we look up the directories' stream object and associate the new file with that object. Once we have a stream object for a file, we use the AG that the stream object point to for allocations. If we can't allocate in that AG (e.g. it is full) we move the entire stream to another AG. Other inodes in the same stream are moved to the new AG on their next allocation (i.e. lazy update). Stream objects are kept in a cache and hold a reference on the inode. Hence the inode cannot be reclaimed while there is an outstanding stream reference. This means that on unlink we need to remove the stream association and we also need to flush all the associations on certain events that want to reclaim all unreferenced inodes (e.g. filesystem freeze). SGI-PV: 964469 SGI-Modid: xfs-linux-melb:xfs-kern:29096a Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Barry Naujok <bnaujok@sgi.com> Signed-off-by: Donald Douwsma <donaldd@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Tim Shimmin <tes@sgi.com> Signed-off-by: Vlad Apostolov <vapo@sgi.com>
2007-07-14[XFS] Lazy Superblock CountersDavid Chinner
When we have a couple of hundred transactions on the fly at once, they all typically modify the on disk superblock in some way. create/unclink/mkdir/rmdir modify inode counts, allocation/freeing modify free block counts. When these counts are modified in a transaction, they must eventually lock the superblock buffer and apply the mods. The buffer then remains locked until the transaction is committed into the incore log buffer. The result of this is that with enough transactions on the fly the incore superblock buffer becomes a bottleneck. The result of contention on the incore superblock buffer is that transaction rates fall - the more pressure that is put on the superblock buffer, the slower things go. The key to removing the contention is to not require the superblock fields in question to be locked. We do that by not marking the superblock dirty in the transaction. IOWs, we modify the incore superblock but do not modify the cached superblock buffer. In short, we do not log superblock modifications to critical fields in the superblock on every transaction. In fact we only do it just before we write the superblock to disk every sync period or just before unmount. This creates an interesting problem - if we don't log or write out the fields in every transaction, then how do the values get recovered after a crash? the answer is simple - we keep enough duplicate, logged information in other structures that we can reconstruct the correct count after log recovery has been performed. It is the AGF and AGI structures that contain the duplicate information; after recovery, we walk every AGI and AGF and sum their individual counters to get the correct value, and we do a transaction into the log to correct them. An optimisation of this is that if we have a clean unmount record, we know the value in the superblock is correct, so we can avoid the summation walk under normal conditions and so mount/recovery times do not change under normal operation. One wrinkle that was discovered during development was that the blocks used in the freespace btrees are never accounted for in the AGF counters. This was once a valid optimisation to make; when the filesystem is full, the free space btrees are empty and consume no space. Hence when it matters, the "accounting" is correct. But that means the when we do the AGF summations, we would not have a correct count and xfs_check would complain. Hence a new counter was added to track the number of blocks used by the free space btrees. This is an *on-disk format change*. As a result of this, lazy superblock counters are a mkfs option and at the moment on linux there is no way to convert an old filesystem. This is possible - xfs_db can be used to twiddle the right bits and then xfs_repair will do the format conversion for you. Similarly, you can convert backwards as well. At some point we'll add functionality to xfs_admin to do the bit twiddling easily.... SGI-PV: 964999 SGI-Modid: xfs-linux-melb:xfs-kern:28652a Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Tim Shimmin <tes@sgi.com>
2006-09-28[XFS] Remove several macros that are no longer used anywhereEric Sandeen
SGI-PV: 955302 SGI-Modid: xfs-linux-melb:xfs-kern:26749a Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Signed-off-by: Nathan Scott <nathans@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2006-06-09[XFS] Add degframentation exclusion supportBarry Naujok
SGI-PV: 953061 SGI-Modid: xfs-linux-melb:xfs-kern:25986a Signed-off-by: Barry Naujok <bnaujok@sgi.com> Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-06-09[XFS] Fix a comment typo, originally noticed by Ming Zhang.Nathan Scott
SGI-PV: 907752 SGI-Modid: xfs-linux-melb:xfs-kern:25921a Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-01-11[XFS] Sort out cosmetic differences between user and kernel copies of someNathan Scott
sources. SGI-PV: 907752 SGI-Modid: xfs-linux-melb:xfs-kern:24659a Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-01-11[XFS] Implement the di_extsize allocator hint for non-realtime files asNathan Scott
well. Also provides a mechanism for inheriting this property from the parent directory for new files. SGI-PV: 945264 SGI-Modid: xfs-linux-melb:xfs-kern:24367a Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02[XFS] Update license/copyright notices to match the prefered SGINathan Scott
boilerplate. SGI-PV: 913862 SGI-Modid: xfs-linux:xfs-kern:23903a Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02[XFS] Ondisk format extension for extended attributes (attr2). Basically,Nathan Scott
the data/attr forks now grow up/down from either end of the literal area, rather than dividing the literal area into two chunks and growing both upward. Means we can now make much more efficient use of the attribute space, incl. fitting DMF attributes inline in 256 byte inodes, and large jumps in dbench3 performance numbers. It is self enabling, but can be forced on/off via the attr2/noattr2 mount options. SGI-PV: 941645 SGI-Modid: xfs-linux:xfs-kern:23835a Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-06-21[XFS] Makes more sense to use the fsxattr interface instead of adding newNathan Scott
ioctls for project IDs. SGI-PV: 938145 SGI-Modid: xfs-linux:xfs-kern:22899a Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-06-21[XFS] Add a get/set interface for XFS project identifiers.Nathan Scott
SGI-PV: 932952 SGI-Modid: xfs-linux:xfs-kern:21938a Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
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!