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path: root/fs/xfs/xfs_iomap.h
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2007-05-08[XFS] Fix to prevent the notorious 'NULL files' problem after a crash.Lachlan McIlroy
The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2005-11-25[XFS] Fix potential overflow in xfs_iomap_t delta for very large extentsEric Sandeen
SGI-PV: 945311 SGI-Modid: xfs-linux-melb:xfs-kern:201708a Signed-off-by: Eric Sandeen <sandeen@sgi.com> 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>
2005-05-05[XFS] Cleanup use of loff_t vs xfs_off_t in the core code.Nathan Scott
SGI Modid: xfs-linux:xfs-kern:22378a Signed-off-by: Nathan Scott <nathans@sgi.com> Signed-off-by: Christoph Hellwig <hch@sgi.com>
2005-05-05[XFS] Use the right offset when ensuring a delayed allocate conversion has ↵Nathan Scott
covered the offset originally requested. Can cause data corruption when multiple processes are performing writeout on different areas of the same file. Quite difficult to hit though. SGI Modid: xfs-linux:xfs-kern:22377a Signed-off-by: Nathan Scott <nathans@sgi.com> Signed-off-by: Christoph Hellwig <hch@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!