There is a possible deadlock between two processes on the same node, where one
process is deleting an inode, and another process is looking for allocated but
unused inodes to delete in order to create more space.
process A does an iput() on inode X, and it's i_count drops to 0. This causes
iput_final() to be called, which puts an inode into state I_FREEING at
generic_delete_inode(). There no point between when iput_final() is called, and
when I_FREEING is set where GFS2 could acquire any glocks. Once I_FREEING is
set, no other process on that node can successfully look up that inode until
the delete finishes.
process B locks the the resource group for the same inode in get_local_rgrp(),
which is called by gfs2_inplace_reserve_i()
process A tries to lock the resource group for the inode in
gfs2_dinode_dealloc(), but it's already locked by process B
process B waits in find_inode for the inode to have the I_FREEING state cleared.
Deadlock.
This patch solves the problem by adding an alternative to gfs2_iget(),
gfs2_iget_skip(), that simply skips any inodes that are in the I_FREEING
state.o The alternate test function is just like the original one, except that
it fails if the inode is being freed, and sets a skipped flag. The alternate
set function is just like the original, except that it fails if the skipped
flag is set. Only try_rgrp_unlink() calls gfs2_iget_skip() instead of
gfs2_iget().
Signed-off-by: Benjamin E. Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
GFS2 has been passing i_mode within NFS File Handle. Other than the
wrong assumption that there is always room for this extra 16 bit value,
the current gfs2_get_dentry doesn't really need the i_mode to work
correctly. Note that GFS2 NFS code does go thru the same lookup code
path as direct file access route (where the mode is obtained from name
lookup) but gfs2_get_dentry() is coded for different purpose. It is not
used during lookup time. It is part of the file access procedure call.
When the call is invoked, if on-disk inode is not in-memory, it has to
be read-in. This makes i_mode passing a useless overhead.
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
GFS2 lookup code doesn't ask for inode shared glock. This implies during
in-memory inode creation for existing file, GFS2 will not disk-read in
the inode contents. This leaves no_formal_ino un-initialized during
lookup time. The un-initialized no_formal_ino is subsequently encoded
into file handle. Clients will get ESTALE error whenever it tries to
access these files.
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes some sign issues which were accidentally introduced
into the quota & statfs code during the endianess annotation process.
Also included is a general clean up which moves all of the _host
structures out of gfs2_ondisk.h (where they should not have been to
start with) and into the places where they are actually used (often only
one place). Also those _host structures which are not required any more
are removed entirely (which is the eventual plan for all of them).
The conversion routines from ondisk.c are also moved into the places
where they are actually used, which for almost every one, was just one
single place, so all those are now static functions. This also cleans up
the end of gfs2_ondisk.h which no longer needs the #ifdef __KERNEL__.
The net result is a reduction of about 100 lines of code, many functions
now marked static plus the bug fixes as mentioned above. For good
measure I ran the code through sparse after making these changes to
check that there are no warnings generated.
This fixes Red Hat bz #239686
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch cleans up the inode number handling code. The main difference
is that instead of looking up the inodes using a struct gfs2_inum_host
we now use just the no_addr member of this structure. The tests relating
to no_formal_ino can then be done by the calling code. This has
advantages in that we want to do different things in different code
paths if the no_formal_ino doesn't match. In the NFS patch we want to
return -ESTALE, but in the ->lookup() path, its a bug in the fs if the
no_formal_ino doesn't match and thus we can withdraw in this case.
In order to later fix bz #201012, we need to be able to look up an inode
without knowing no_formal_ino, as the only information that is known to
us is the on-disk location of the inode in question.
This patch will also help us to fix bz #236099 at a later date by
cleaning up a lot of the code in that area.
There are no user visible changes as a result of this patch and there
are no changes to the on-disk format either.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
On Thu, Jan 11, 2007 at 10:26:27PM -0800, Andrew Morton wrote:
>...
> Changes since 2.6.20-rc3-mm1:
>...
> git-gfs2-nmw.patch
>...
> git trees
>...
This patch makes the needlessly globlal gfs2_change_nlink_i() static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Second round of gfs2_rename lock re-ordering to allow Anaconda adding
root partition on top of gfs2. Previous to this patch the recursive
lock detector in glock.c can be triggered due to attempting to lock
the rgrp twice. This fixes it by checking to see whether the rgrp
is already locked.
This fixes Red Hat bugzilla #221237
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Bugzilla 215088
Fix deadlock in gfs2_change_nlink() while installing RHEL5 into GFS2
partition. The gfs2_rename() apparently needs block allocation for the
new name (into the directory) where it requires rg locks. At the same
time, while updating the nlink count for the replaced file,
gfs2_change_nlink() tries to return the inode meta-data back to resource
group where it needs rg locks too. Our logic doesn't allow process to
acquire these locks recursively by the same process (RHEL installer)
that results a BUG call. This only happens within rename code path and
only if the destination file exists before the rename operation.
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The gfs2_glock_nq_m_atime function is unused in so far as its only
ever called with num_gh = 1, and this falls through to the
gfs2_glock_nq_atime function, so we might as well call that directly.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This function wasn't really doing the right thing. There was no need
to update the inode size at this point and the updating of the
i_blocks field has now been moved to the places where di_blocks is
updated. A result of this patch and some those preceeding it is that
unlocking a glock is now a much more efficient process, since there
is no longer any requirement to copy data from the gfs2 inode into
the vfs inode at this point.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Remove the di_[amc]time fields and use inode->i_[amc]time
fields instead. This saves 24 bytes from the gfs2_inode.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This removes the duplicate di_mode field in favour of using the
inode->i_mode field. This saves 4 bytes.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This removes the device numbers from this structure by using
inode->i_rdev instead. It also cleans up the code in gfs2_mknod.
It results in shrinking the gfs2_inode by 8 bytes.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
As per comments from Jan Engelhardt <jengelh@linux01.gwdg.de> this
updates the copyright message to say "version" in full rather than
"v.2". Also incore.h has been updated to remove forward structure
declarations which are not required.
The gfs2_quota_lvb structure has now had endianess annotations added
to it. Also quota.c has been updated so that we now store the
lvb data locally in endian independant format to avoid needing
a structure in host endianess too. As a result the endianess
conversions are done as required at various points and thus the
conversion routines in lvb.[ch] are no longer required. I've
moved the one remaining constant in lvb.h thats used into lm.h
and removed the unused lvb.[ch].
I have not changed the HIF_ constants. That is left to a later patch
which I hope will unify the gh_flags and gh_iflags fields of the
struct gfs2_holder.
Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
gfs2_repermission is just a wrapper for permission, so remove it and
call permission directly where required.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes the way we have been dealing with unlinked,
but still open files. It removes all limits (other than memory
for inodes, as per every other filesystem) on numbers of these
which we can support on GFS2. It also means that (like other
fs) its the responsibility of the last process to close the file
to deallocate the storage, rather than the person who did the
unlinking. Note that with GFS2, those two events might take place
on different nodes.
Also there are a number of other changes:
o We use the Linux inode subsystem as it was intended to be
used, wrt allocating GFS2 inodes
o The Linux inode cache is now the point which we use for
local enforcement of only holding one copy of the inode in
core at once (previous to this we used the glock layer).
o We no longer use the unlinked "special" file. We just ignore it
completely. This makes unlinking more efficient.
o We now use the 4th block allocation state. The previously unused
state is used to track unlinked but still open inodes.
o gfs2_inoded is no longer needed
o Several fields are now no longer needed (and removed) from the in
core struct gfs2_inode
o Several fields are no longer needed (and removed) from the in core
superblock
There are a number of future possible optimisations and clean ups
which have been made possible by this patch.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Despite my earlier careful search, there was a recursive lock left
in the deallocation code. This removes it. It also should speed up
deallocation be reducing the number of locking operations which take
place by using two "try lock" operations on the two locks involved in
inode deallocation which allows us to grab the locks out of order
(compared with NFS which grabs the inode lock first and the iopen
lock later). It is ok for us to fail while doing this since if it
does fail it means that someone else is still using the inode and
thus it wouldn't be possible to deallocate anyway.
This fixes the bug reported to me by Rob Kenna.
Cc: Rob Kenna <rkenna@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Due to a typo, the dir leaf split operation was (for the first
split in a directory) writing the new hash vaules at the
wrong offset. This is now fixed.
Also some other tidy ups are included:
- We use GFS2's hash function for dentries (see ops_dentry.c) so that
we don't have to keep recalculating the hash values.
- A lot of common code is eliminated between the various directory
lookup routines.
- Better error checking on directory lookup (previously different
routines checked for different errors)
- The leaf split operation has a couple of redundant operations
removed from it, so it should be faster.
There is still further scope for further clean ups in the directory
code, and readdir in particular could do with slimming down a bit.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
We no longer lookup ".gfs2_admin" in the root directory in order to
find it, but instead use the inode number given in the superblock.
Both the root directory and the admin directory are now looked up using
the same routine, so the redundant code is removed.
Also, there is no longer a reference to the root inode in the
GFS2 super block. When required this can be retreived via
sb->s_root->d_inode instead.
Assuming that we introduce a metadata filesystem type for GFS, then
this is a first step towards that goal.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Umount is now working correctly again. The bug was due to
not getting an extra ref count when mounting the fs. We
should have bumped it by two (once for the internal pointer
to the root inode from the super block and once for the
inode hanging off the dcache entry for root).
Also this patch tidys up the code dealing with looking up
and creating inodes. We now pass Linux inodes (with gfs2_inodes
attached) rather than the other way around and this reduces code
duplication in various places.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This is a very large patch, with a few still to be resolved issues
so you might want to check out the previous head of the tree since
this is known to be unstable. Fixes for the various bugs will be
forthcoming shortly.
This patch removes the special data format which has been used
up till now for journaled data files. Directories still retain the
old format so that they will remain on disk compatible with earlier
releases. As a result you can now do the following with journaled
data files:
1) mmap them
2) export them over NFS
3) convert to/from normal files whenever you want to (the zero length
restriction is gone)
In addition the level at which GFS' locking is done has changed for all
files (since they all now use the page cache) such that the locking is
done at the page cache level rather than the level of the fs operations.
This should mean that things like loopback mounts and other things which
touch the page cache directly should now work.
Current known issues:
1. There is a lock mode inversion problem related to the resource
group hold function which needs to be resolved.
2. Any significant amount of I/O causes an oops with an offset of hex 320
(NULL pointer dereference) which appears to be related to a journaled data
buffer appearing on a list where it shouldn't be.
3. Direct I/O writes are disabled for the time being (will reappear later)
4. There is probably a deadlock between the page lock and GFS' locks under
certain combinations of mmap and fs operation I/O.
5. Issue relating to ref counting on internally used inodes causes a hang
on umount (discovered before this patch, and not fixed by it)
6. One part of the directory metadata is different from GFS1 and will need
to be resolved before next release.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Add the new external read function. Its temporarily in jdata.c
even though the protoype is in ops_file.h - this will change
shortly. The current implementation will change to a page cache
one when that happens.
In order to effect the above changes, the various internal inodes
now have Linux inodes attached to them. We keep the references to
the Linux inodes, rather than the gfs2_inodes in the super block.
In order to get everything to work correctly I've had to reorder
the init sequence on mount (which I should probably have done
earlier when .gfs2_admin was made visible).
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch contains all the core files for GFS2.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Benjamin Marzinski