Commit graph

86 commits

Author SHA1 Message Date
Steven Whitehouse
b6397893a5 [GFS2] Use hlist for glock hash chains
This results in smaller list heads, so that we can have more chains
in the same amount of memory (twice as many). I've multiplied the
size of the table by four though - this is because we are saving
memory by not having one lock per chain any more. So we land up
using about the same amount of memory for the hash table as we
did before I started these changes, the difference being that we
now have four times as many hash chains.

The reason that I say "about the same amount of memory" is that the
actual amount now depends upon the NR_CPUS and some of the config
variables, so that its not exact and in some cases we do use more
memory. Eventually we might want to scale the hash table size
according to the size of physical ram as measured on module load.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-12 10:10:01 -04:00
Steven Whitehouse
2426443460 [GFS2] Rewrite of examine_bucket()
The existing implementation of this function in glock.c was not
very efficient as it relied upon keeping a cursor element upon the
hash chain in question and moving it along. This new version improves
upon this by using the current element as a cursor. This is possible
since we only look at the "next" element in the list after we've
taken the read_lock() subsequent to calling the examiner function.
Obviously we have to eventually drop the ref count that we are then
left with and we cannot do that while holding the read_lock, so we
do that next time we drop the lock. That means either just before
we examine another glock, or when the loop has terminated.

The new implementation has several advantages: it uses only a
read_lock() rather than a write_lock(), so it can run simnultaneously
with other code, it doesn't need a "plug" element, so that it removes
a test not only from this list iterator, but from all the other glock
list iterators too. So it makes things faster and smaller.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-11 21:40:30 -04:00
Steven Whitehouse
087efdd391 [GFS2] Make glock hash locks proportional to NR_CPUS
Make the number of locks used for hash chains in glock.c
proportional to NR_CPUS. Also move constants for the number
of hash chains into glock.c from incore.h since they are
not used outside of glock.c.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-09 16:59:11 -04:00
Steven Whitehouse
37b2fa6a24 [GFS2] Move rwlocks in glock.c into their own array
This splits the rwlocks guarding the hash chains of the glock hash
table into their own array. This will reduce memory usage in some
cases due to better alignment, although the real reason for doing it
is to allow the two tables to be different sizes in future (i.e.
the locks will be sized proportionally with the max number of CPUs
and the hash chains sized proportinally with the size of physical memory)

In order to allow this, the gl_bucket member of struct gfs2_glock has
now become gl_hash, so we record the hash rather than a pointer to the
bucket itself.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-08 13:35:56 -04:00
Steven Whitehouse
9b47c11d1c [GFS2] Use void * instead of typedef for locking module interface
As requested by Jan Engelhardt, this removes the typedefs in the
locking module interface and replaces them with void *. Also
since we are changing the interface, I've added a few consts
as well.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Cc: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-08 10:17:58 -04:00
Steven Whitehouse
85d1da67f7 [GFS2] Move glock hash table out of superblock
There are several reasons why we want to do this:
 - Firstly its large and thus we'll scale better with multiple
   GFS2 fs mounted at the same time
 - Secondly its easier to scale its size as required (thats a plan
   for later patches)
 - Thirdly, we can use kzalloc rather than vmalloc when allocating
   the superblock (its now only 4888 bytes)
 - Fourth its all part of my plan to eventually be able to use RCU
   with the glock hash.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-07 14:40:21 -04:00
Steven Whitehouse
f2f7ba5237 [GFS2] Make headers compile on their own
As per Jan Engelhardt's comments, this should make all the headers
compile on their own by including and/or declaring structures
early.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-05 10:39:21 -04:00
Steven Whitehouse
cd915493fc [GFS2] Change all types to uX style
This makes all fixed size types have consistent names.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-04 12:49:07 -04:00
Steven Whitehouse
e9fc2aa091 [GFS2] Update copyright, tidy up incore.h
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>
2006-09-01 11:05:15 -04:00
Steven Whitehouse
5e2b0613ed [GFS2] Remove unused code from glock layer
Remove the unused sync feature from glocks. This is currently done by
calling the required functions to sync pages/blocks directly so this
code isn't needed.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-08-30 09:38:30 -04:00
Steven Whitehouse
8fb4b536e7 [GFS2] Make glock operations const
For all the usual reasons of enforcing correctness and potentially
reducing code size, this patch makes the glock operations const.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-08-30 09:30:00 -04:00
Abhijith Das
8638460540 [GFS2] Allow mounting of gfs2 and gfs2meta at the same time
This patch allows the simultaneous mounting of gfs2meta and gfs2
filesystems. A restriction however is that a gfs2meta fs may only be
mounted if its corresponding gfs2 filesystem is also mounted. Also, a
gfs2 filesystem cannot be unmounted before its gfs2meta filesystem.

Signed-off-by: Abhijith Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-08-25 17:19:55 -04:00
Steven Whitehouse
a2242db090 [GFS2] Speed up scanning of glocks
I noticed the gfs2_scand seemed to be taking a lot of CPU,
so in order to cut that down a bit, here is a patch. Firstly
the type of a glock is a constant during its lifetime, so that
its possible to check this without needing locking. I've moved
the (common) case of testing for an inode glock outside of
the glmutex lock.

Also there was a mutex left over from when the glock cache was
master of the inode cache. That isn't required any more so I've
removed that too.

There is probably scope for further speed ups in the future
in this area.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-08-24 17:03:05 -04:00
Steven Whitehouse
59a1cc6bda [GFS2] Fix lock ordering bug in page fault path
Mmapped files were able to trigger a lock ordering bug. Private
maps do not need to take the glock so early on. Shared maps do
unfortunately, however we can get around that by adding a flag
into the flags for the struct gfs2_file. This only works because
we are taking an exclusive lock at this point, so we know that
nobody else can be racing with us.

Fixes Red Hat bugzilla: #201196

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-08-04 15:41:22 -04:00
Steven Whitehouse
bdd512aeea [GFS2] Remove unused flag
The flag GIF_MIN_INIT is no longer used or required.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-06-22 15:26:33 -04:00
David Woodhouse
695165dfba [GFS2] Fix use of bitops on unsigned int (struct gfs2_holder->gh_iflags)
fs/gfs2/glock.c: In function ‘gfs2_holder_get’:
fs/gfs2/glock.c:439: warning: passing argument 2 of ‘set_bit’ from incompatible pointer type
fs/gfs2/glock.c: In function ‘rq_promote’:
fs/gfs2/glock.c:512: warning: passing argument 2 of ‘set_bit’ from incompatible pointer type
fs/gfs2/glock.c:526: warning: passing argument 2 of ‘set_bit’ from incompatible pointer type
 ...

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-06-20 13:44:27 +01:00
Steven Whitehouse
feaa7bba02 [GFS2] Fix unlinked file handling
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>
2006-06-14 15:32:57 -04:00
Steven Whitehouse
6b61b072a8 [GFS2] Move some fields around to reduce wasted space
We can reclaim some space by moving fields in some structures
in order to allow them to pack better on 64 bit architectures.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-06-06 14:49:39 -04:00
Steven Whitehouse
320dd101e2 [GFS2] glock debugging and inode cache changes
This adds some extra debugging to glock.c and changes
inode.c's deallocation code to call the debugging code
at a suitable moment. I'm chasing down a particular bug
to do with deallocation at the moment and the code can
go again once the bug is fixed.

Also this includes the first part of some changes to unify
the Linux struct inode and GFS2's struct gfs2_inode. This
transformation will happen in small parts over the next short
period.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-18 16:25:27 -04:00
Steven Whitehouse
3a8a9a1034 [GFS2] Update copyright date to 2006
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-18 15:09:15 -04:00
Steven Whitehouse
5965b1f479 [GFS2] Don't do recursive locking in glock layer
This patch changes the last user of recursive locking so that
it no longer needs this feature and removes it from the glock
layer. This makes the glock code a lot simpler and easier to
understand. Its also a prerequsite to adding support for the
AOP_TRUNCATED_PAGE return code (or at least it is if you don't
want your brain to melt in the process)

I've left in a couple of checks just in case there is some place
else in the code which is still using this feature that I didn't
spot yet, but they can probably be removed long term.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-26 13:21:55 -04:00
Steven Whitehouse
fe1bdedc6c [GFS2] Use vmalloc() in dir code
When allocating memory to sort directory entries, use vmalloc()
rather than kmalloc() since for larger directories, the required
size can easily be graeter than the 128k maximum of kmalloc().

Also adding the first steps towards getting the AOP_TRUNCATED_PAGE
return code get in the glock code by flagging all places where we
request a glock and we are holding a page lock.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-18 10:09:15 -04:00
Steven Whitehouse
b09e593d79 [GFS2] Fix a ref count bug and other clean ups
This fixes a ref count bug that sometimes showed up a umount time
(causing it to hang) but it otherwise mostly harmless. At the same
time there are some clean ups including making the log operations
structures const, moving a memory allocation so that its not done
in the fast path of checking to see if there is an outstanding
transaction related to a particular glock.

Removes the sd_log_wrap varaible which was updated, but never actually
used anywhere. Updates the gfs2 ioctl() to run without the kernel lock
(which it never needed anyway). Removes the "invalidate inodes" loop
from GFS2's put_super routine. This is done in kill super anyway so
we don't need to do it here. The loop was also bogus in that if there
are any inodes "stuck" at this point its a bug and we need to know
about it rather than hide it by hanging forever.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-07 11:17:32 -04:00
Steven Whitehouse
55eccc6d00 [GFS2] Finish off ioctl support
This puts the finishing touches to the ioctl support and also
removes a couple of unused fields from GFS2's private per file
structure.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-04 14:29:30 -04:00
Steven Whitehouse
d0dc80dbaf [GFS2] Update debugging code
Update the debugging code in trans.c and at the same time improve
the debugging code for gfs2_holders. The new code should be pretty
fast during the normal case and provide just as much information
in case of errors (or more).

One small function from glock.c has moved to glock.h as a static inline so
that its return address won't get in the way of the debugging.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-03-29 14:36:49 -05:00
Steven Whitehouse
484adff8a0 [GFS2] Update locking in log.c
Replace the lock_for_trans()/lock_for_flush() functions with an rwsem.
In fact the sd_log_flush_lock becomes an rwsem (the write part of it)
and is extended slightly to cover everything that the lock_for_flush()
used to cover. The read part of the lock is instead of lock_for_trans().

This corrects the races in the original code and reduces the code size.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-03-29 09:12:12 -05:00
Steven Whitehouse
71b86f562b [GFS2] Further updates to dir and logging code
This reduces the size of the directory code by about 3k and gets
readdir() to use the functions which were introduced in the previous
directory code update.

Two memory allocations are merged into one. Eliminates zeroing of some
buffers which were never used before they were initialised by
other data.

There is still scope for further improvement in the directory code.

On the logging side, a hand created mutex has been replaced by a
standard Linux mutex in the log allocation code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-03-28 14:14:04 -05:00
Steven Whitehouse
c9fd43078f [GFS2] Tidy up mount code.
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>
2006-03-01 15:31:02 -05:00
Steven Whitehouse
e317ffcb7c [GFS2] Remove uneeded memory allocation
For every filesystem operation where we need a transaction, we
now make one less memory allocation.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-03-01 11:39:37 -05:00
Steven Whitehouse
5c676f6d35 [GFS2] Macros removal in gfs2.h
As suggested by Pekka Enberg <penberg@cs.helsinki.fi>.

The DIV_RU macro is renamed DIV_ROUND_UP and and moved to kernel.h
The other macros are gone from gfs2.h as (although not requested
by Pekka Enberg) are a number of included header file which are now
included individually. The inode number comparison function is
now an inline function.

The DT2IF and IF2DT may be addressed in a future patch.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-27 17:23:27 -05:00
David Teigland
6a6b3d018f [GFS2] Patch to remove stats gathering from GFS2
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-23 10:11:47 +00:00
Steven Whitehouse
f55ab26a8f [GFS2] Use mutices rather than semaphores
As well as a number of minor bug fixes, this patch changes GFS
to use mutices rather than semaphores. This results in better
information in case there are any locking problems.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-21 12:51:39 +00:00
Steven Whitehouse
7359a19cc7 [GFS2] Fix for root inode ref count bug
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>
2006-02-13 12:27:43 +00:00
Steven Whitehouse
f42faf4fa4 [GFS2] Add gfs2_internal_read()
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>
2006-01-30 18:34:10 +00:00
Steven Whitehouse
64fb4eb7d4 [GFS2] Remove gfs2_databuf in favour of gfs2_bufdata structure
Removing the gfs2_databuf structure and using gfs2_bufdata instead
is a step towards allowing journaling of data without requiring the
metadata header on each journaled block. The idea is to merge the
code paths for ordered data with that of journaled data, with the
log operations in lops.c tacking account of the different types of
buffers as they are presented to it. Largely the code path for
metadata will be similar too, but obviously through a different set
of log operations.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-18 13:14:40 +00:00
David Teigland
b3b94faa5f [GFS2] The core of GFS2
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>
2006-01-16 16:50:04 +00:00