file operations ->write(), ->aio_write(), and ->writev() for regular
files. This replaces the old use of generic_file_write(), et al and
the address space operations ->prepare_write and ->commit_write.
This means that both sparse and non-sparse (unencrypted and
uncompressed) files can now be extended using the normal write(2)
code path. There are two limitations at present and these are that
we never create sparse files and that we only have limited support
for highly fragmented files, i.e. ones whose data attribute is split
across multiple extents. When such a case is encountered,
EOPNOTSUPP is returned.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
and cond_resched() in the main loop as we could be dirtying a lot of
pages and this ensures we play nice with the VM and the system as a
whole.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
the initial implementation of file truncation. Now both open(2)ing
a file with the O_TRUNC flag and the {,f}truncate(2) system calls
will resize a file appropriately. The limitations are that only
uncompressed and unencrypted files are supported. Also, there is
only very limited support for highly fragmented files (the ones whose
$DATA attribute is split into multiple attribute extents).
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
extend the allocation of an attributes. Optionally, the data size,
but not the initialized size can be extended, too.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
which is zero for a resident attribute but should no longer be zero
once the attribute is non-resident as it then has real clusters
allocated.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
as an extra parameter. This is needed since we need to know the size
before we can map the mft record and our callers always know it. The
reason we cannot simply read the size from the vfs inode i_size is
that this is not necessarily uptodate. This happens when
ntfs_attr_make_non_resident() is called in the ->truncate call path.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
specifying whether the cluster are being allocated to extend an
attribute or to fill a hole.
- Change ntfs_attr_make_non_resident() to call ntfs_cluster_alloc()
with @is_extension set to TRUE and remove the runlist terminator
fixup code as this is now done by ntfs_cluster_alloc().
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
search context as argument. This allows calling it with the mft
record mapped. Update all callers.
- Fix potential deadlock in ntfs_mft_data_extend_allocation_nolock()
error handling by passing in the active search context when calling
ntfs_cluster_free().
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
search context as argument. This allows calling it with the mft
record mapped. Update all callers.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
restart pages in the journal without multi sector transfer protection
fixups (i.e. the update sequence array is empty and in fact does not
exist).
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
since we otherwise get into a lock reversal deadlock if a read locked
runlist is passed in. In the process also change it to take an ntfs
inode instead of a vfs inode as parameter.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
an octal number to conform to how chmod(1) works, too. Thanks to
Giuseppe Bilotta and Horst von Brand for pointing out the errors of
my ways.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
fs/ntfs/aops.c::ntfs_end_buffer_async_read() to a bit spin lock
in the first buffer head of a page.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
lock protection over the buffer submission for i/o which allows the
removal of the get_bh()/put_bh() pairs for each buffer.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
Also, add BUG() checks to ntfs_attr_make_non_resident() and
ntfs_attr_set() to ensure that these functions are never called
for compressed or encrypted attributes.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
- Fix a bug in ntfs_map_runlist_nolock() where we forgot to protect
access to the allocated size in the ntfs inode with the size lock.
- Fix ntfs_attr_vcn_to_lcn_nolock() and ntfs_attr_find_vcn_nolock() to
return LCN_ENOENT when there is no runlist and the allocated size is
zero.
- Fix load_attribute_list() to handle the case of a NULL runlist.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
index entry is in the index root, we forgot to set the @ir pointer in
the index context. Thanks for Yura Pakhuchiy for finding this bug.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
in the two critical regions. This means we no longer need to
panic() when the allocation fails as it now cannot fail.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
- Modify fs/ntfs/malloc.h::ntfs_malloc_nofs() to do the kmalloc() based
allocations with __GFP_HIGHMEM, analogous to how the vmalloc() based
allocations are done.
- Add fs/ntfs/malloc.h::ntfs_malloc_nofs_nofail() which is analogous to
ntfs_malloc_nofs() but it performs allocations with __GFP_NOFAIL and
hence cannot fail.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
- Support journals ($LogFile) which have been modified by chkdsk. This
means users can boot into Windows after we marked the volume dirty.
The Windows boot will run chkdsk and then reboot. The user can then
immediately boot into Linux rather than having to do a full Windows
boot first before rebooting into Linux and we will recognize such a
journal and empty it as it is clean by definition.
- Support journals ($LogFile) with only one restart page as well as
journals with two different restart pages. We sanity check both and
either use the only sane one or the more recent one of the two in the
case that both are valid.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
the buffers when mapping them after the VM had discarded them.
Thanks to Martin MOKREJŠ for the bug report.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
The situation: VFS inode X on a mounted ntfs volume is dirty. For
same inode X, the ntfs_inode is dirty and thus corresponding on-disk
inode, i.e. mft record, which is in a dirty PAGE_CACHE_PAGE belonging
to the table of inodes, i.e. $MFT, inode 0.
What happens:
Process 1: sys_sync()/umount()/whatever... calls
__sync_single_inode() for $MFT -> do_writepages() -> write_page for
the dirty page containing the on-disk inode X, the page is now locked
-> ntfs_write_mst_block() which clears PageUptodate() on the page to
prevent anyone else getting hold of it whilst it does the write out.
This is necessary as the on-disk inode needs "fixups" applied before
the write to disk which are removed again after the write and
PageUptodate is then set again. It then analyses the page looking
for dirty on-disk inodes and when it finds one it calls
ntfs_may_write_mft_record() to see if it is safe to write this
on-disk inode. This then calls ilookup5() to check if the
corresponding VFS inode is in icache(). This in turn calls ifind()
which waits on the inode lock via wait_on_inode whilst holding the
global inode_lock.
Process 2: pdflush results in a call to __sync_single_inode for the
same VFS inode X on the ntfs volume. This locks the inode (I_LOCK)
then calls write-inode -> ntfs_write_inode -> map_mft_record() ->
read_cache_page() for the page (in page cache of table of inodes
$MFT, inode 0) containing the on-disk inode. This page has
PageUptodate() clear because of Process 1 (see above) so
read_cache_page() blocks when it tries to take the page lock for the
page so it can call ntfs_read_page().
Thus Process 1 is holding the page lock on the page containing the
on-disk inode X and it is waiting on the inode X to be unlocked in
ifind() so it can write the page out and then unlock the page.
And Process 2 is holding the inode lock on inode X and is waiting for
the page to be unlocked so it can call ntfs_readpage() or discover
that Process 1 set PageUptodate() again and use the page.
Thus we have a deadlock due to ifind() waiting on the inode lock.
The solution: The fix is to use the newly introduced
ilookup5_nowait() which does not wait on the inode's lock and hence
avoids the deadlock. This is safe as we do not care about the VFS
inode and only use the fact that it is in the VFS inode cache and the
fact that the vfs and ntfs inodes are one struct in memory to find
the ntfs inode in memory if present. Also, the ntfs inode has its
own locking so it does not matter if the vfs inode is locked.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
