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>
This change addresses a race in xfs_write() where, for direct I/O, the
flags need_i_mutex and need_flush are setup before the iolock is acquired.
The logic used to setup the flags may change between setting the flags and
acquiring the iolock resulting in these flags having incorrect values. For
example, if a file is not currently cached then need_i_mutex is set to
zero and then if the file is cached before the iolock is acquired we will
fail to do the flushinval before the direct write.
The flush (and also the call to xfs_zero_eof()) need to be done with the
iolock held exclusive so we need to acquire the iolock before checking for
cached data (or if the write begins after eof) to prevent this state from
changing. For direct I/O I've chosen to always acquire the iolock in
shared mode initially and if there is a need to promote it then drop it
and reacquire it.
There's also some other tidy-ups including removing the O_APPEND offset
adjustment since that work is done in generic_write_checks() (and we don't
use offset as an input parameter anywhere).
SGI-PV: 962170
SGI-Modid: xfs-linux-melb:xfs-kern:28319a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
This patch handles error return values in fs_flush_pages and
fs_flushinval_pages. It changes the prototype of fs_flushinval_pages so we
can propogate the errors and handle them at higher layers. I also modified
xfs_itruncate_start so that it could propogate the error further.
SGI-PV: 961990
SGI-Modid: xfs-linux-melb:xfs-kern:28231a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Stewart Smith <stewart@flamingspork.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
kmap() is inefficient and does not scale well. kmap_atomic() is a better
choice. Use the generic wrapper function instead of open coding the
kmap-memset-dcache flush-kunmap stuff.
SGI-PV: 960904
SGI-Modid: xfs-linux-melb:xfs-kern:28041a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tim Shimmin <tes@sgi.com>
xfs_mac.h and xfs_cap.h provide definitions and macros that aren't used
anywhere in XFS at all. They are left-overs from "to be implement at some
point in the future" functionality that Irix XFS has. If this
functionality ever goes into Linux, it will be provided at a different
layer, most likely through the security hooks in the kernel so we will
never need this functionality in XFS.
Patch provided by Eric Sandeen (sandeen@sandeen.net).
SGI-PV: 960895
SGI-Modid: xfs-linux-melb:xfs-kern:28036a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
The problem is the two callers of xfs_iozero() are rounding out the range
to be zeroed to the end of a fsb and in some cases this extends past the
new eof. The call to commit_write() in xfs_iozero() will cause the Linux
inode's file size to be set too high.
SGI-PV: 960788
SGI-Modid: xfs-linux-melb:xfs-kern:28013a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in the xfs
filesystem.
Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch cleans up generic_file_*_read/write() interfaces. Christoph
Hellwig gave me the idea for this clean ups.
In a nutshell, all filesystems should set .aio_read/.aio_write methods and use
do_sync_read/ do_sync_write() as their .read/.write methods. This allows us
to cleanup all variants of generic_file_* routines.
Final available interfaces:
generic_file_aio_read() - read handler
generic_file_aio_write() - write handler
generic_file_aio_write_nolock() - no lock write handler
__generic_file_aio_write_nolock() - internal worker routine
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
xfs_splice_write() failed to update the on disk inode size when extending
the so when the file was closed the range extended by splice was truncated
off. Hence any region of a file written to by splice would end up as a
hole full of zeros.
SGI-PV: 955939
SGI-Modid: xfs-linux-melb:xfs-kern:26920a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: David Chatterton <chatz@sgi.com>
__blockdev_direct_IO for the DIO_OWN_LOCKING case for direct I/O reads
since it drops and reacquires the i_mutex while holding the iolock and
this violates the locking order.
SGI-PV: 955696
SGI-Modid: xfs-linux-melb:xfs-kern:26898a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chatterton <chatz@sgi.com>
the range spanned by modifications to the in-core extent map. Add
XFS_BUNMAPI() and XFS_SWAP_EXTENTS() macros that call xfs_bunmapi() and
xfs_swap_extents() via the ioops vector. Change all calls that may modify
the in-core extent map for the data fork to go through the ioops vector.
This allows a cache of extent map data to be kept in sync.
SGI-PV: 947615
SGI-Modid: xfs-linux-melb:xfs-kern:209226a
Signed-off-by: Olaf Weber <olaf@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
We need not use ->f_pos as the offset for the file input/output. If the
user passed an offset pointer in through sys_splice(), just use that and
leave ->f_pos alone.
Signed-off-by: Jens Axboe <axboe@suse.de>
separate out the 'internal pipe object' abstraction, and make it
usable to splice. This cleans up and fixes several aspects of the
internal splice APIs and the pipe code:
- pipes: the allocation and freeing of pipe_inode_info is now more symmetric
and more streamlined with existing kernel practices.
- splice: small micro-optimization: less pointer dereferencing in splice
methods
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Update XFS for the ->splice_read/->splice_write changes.
Signed-off-by: Jens Axboe <axboe@suse.de>
the trace.
SGI-PV: 948300
SGI-Modid: xfs-linux-melb:xfs-kern:208069a
Signed-off-by: Yingping Lu <yingping@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
else we can hit a delalloc-extents-via-direct-io BUG.
SGI-PV: 949916
SGI-Modid: xfs-linux-melb:xfs-kern:25483a
Signed-off-by: Nathan Scott <nathans@sgi.com>
was caused by ENOSPC but not Rreclaimed by xfs_release or xfs_inactive.
The fix changed the condition in xfs_release and xfs_inactive to invoke
xfs_inactive_free_eofblocks for this special case, changed
xfs_inactive_free_eofblocks to clean the delayed blks after eof. It also
changed xfs_write to set correct eof when ENOSPC occurs.
SGI-PV: 946267
SGI-Modid: xfs-linux-melb:xfs-kern:203788a
Signed-off-by: Yingping Lu <yingping@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
updates and only sync back to the xfs inode when nessecary
SGI-PV: 946679
SGI-Modid: xfs-linux-melb:xfs-kern:203362a
Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
To allow various options to work per-mount instead of per-sb we need a
struct vfsmount when updating ctime and mtime. This preparation patch
replaces the inode_update_time routine with a file_update_atime routine so
we can easily get at the vfsmount. (and the file makes more sense in this
context anyway). Also get rid of the unused second argument - we always
want to update the ctime when calling this routine.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.
Modified-by: Ingo Molnar <mingo@elte.hu>
(finished the conversion)
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
because aio+dio completions may happen from irq context but we need
process context for converting unwritten extents. We also queue regular
direct I/O completions to workqueue for regularity, there's only one
queue_work call per syscall.
SGI-PV: 934766
SGI-Modid: xfs-linux:xfs-kern:196857a
Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
direct I/O locking changes it is just a wrapper around
VOP_FLUSHINVAL_PAGES, so it's not nessecary anymore. Keep a simplified
version for kernels < 2.4.22, as these don't have the changed direct I/O
locking.
SGI-PV: 938064
SGI-Modid: xfs-linux:xfs-kern:194420a
Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
handling for unwritten extents can be moved out of interrupt context.
SGI Modid: xfs-linux:xfs-kern:22343a
Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Christoph Hellwig <hch@sgi.com>
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!
