This patch is based on an idea from Steve Whitehouse. The idea is
to dump the number of pages for inodes in the glock dumps.
The additional locking required me to drop const from quite a few
places.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Field bd_ops was set but never used, so I removed it, and all
code supporting it.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This field indicates the size of the bitmap in bytes, similar to how the
bi_blocks field indicates the size of the bitmap in blocks.
In count_unlinked, replace an instance of bi_bytes * GFS2_NBBY by
bi_blocks.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Steven Whitehouse <swhiteho@redhat.com>
Move the rs_sizehint and rs_rgd_gh fields from struct gfs2_blkreserv
into the inode: they are more closely related to the inode than to a
particular reservation.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Steven Whitehouse <swhiteho@redhat.com>
When an io error is hit, it calls gfs2_io_error_bh_i for every
journal buffer it can't write. Since we changed gfs2_io_error_bh_i
recently to withdraw later in the cycle, it sends a flood of
errors to the console. This patch checks for the file system already
being withdrawn, and if so, doesn't send more messages. It doesn't
stop the flood of messages, but it slows it down and keeps it more
reasonable.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Function gfs2_testbit is called in three places. Two of those places,
gfs2_alloc_extent and gfs2_unaligned_extlen, should be using the clone
bitmaps, not the "real" bitmaps. Function gfs2_unaligned_extlen is used
by the block reservations scheme to determine the length of an extent of
free blocks. Before this patch, it wasn't using the clone bitmap, which
means recently-freed blocks were treated as free blocks for the purposes
of an allocation.
This patch adds a new parameter to gfs2_testbit to indicate whether or
not the clone bitmaps should be used (if available).
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
GFS2 remembers the last rgrp used for allocations in ip->i_rgd.
However, block allocations are made by way of a reservations structure,
ip->i_res, which keeps the last rgrp in ip->i_res.rs_rgd, and ip->i_res
is kept in sync with ip->i_res.rs_rgd, so it's redundant. Get rid of
ip->i_rgd and just use ip->i_res.rs_rgd in its place.
Based on patches by Robert Peterson.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch, block reservations kept track of the inode
number. At one point, that was a valid thing to do. However, since
we made the reservation a part of the inode (rather than a pointer
to a separate allocated object) the reservation can determine the
inode number by using container_of. This saves us a little memory
in our inode.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_free_extlen calculates the length of an extent of
free blocks that may be reserved. The end pointer was calculated as
end = start + bh->b_size but b_size is incorrect because the
bitmap usually stops prior to the end of the buffer data on
the last bitmap.
What this means is that when you do a write, you can reserve a
chunk of blocks that runs off the end of the last bitmap. For
example, I've got a file system where there is only one bitmap
for each rgrp, so ri_length==1. I saw cases in which iozone
tried to do a big write, grabbed a large block reservation,
chose rgrp 5464152, which has ri_data0 5464153 and ri_data 8188.
So 5464153 + 8188 = 5472341 which is the end of the rgrp.
When it grabbed a reservation it got back: 5470936, length 7229.
But 5470936 + 7229 = 5478165. So the reservation starts inside
the rgrp but runs 5824 blocks past the end of the bitmap.
This patch fixes the calculation so it won't exceed the last
bitmap. It also adds a BUG_ON to guard against overflows in the
future.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
GFS2 keeps two arrarys in the superblock that define the maximum size of
an inode depending on the inode's height: sdp->sd_heightsize defines the
heights in units of sb->s_blocksize; sdp->sd_jheightsize defines them in
units of sb->s_blocksize - sizeof(struct gfs2_meta_header). These
arrays are used to determine when additional layers of indirect blocks
are needed. The second array is used for directories which have an
additional gfs2_meta_header at the beginning of each block.
Distinguishing between these two cases makes no sense: the height
required for representing N blocks will come out the same no matter if
the calculation is done in gross (sb->s_blocksize) or net
(sb->s_blocksize - sizeof(struct gfs2_meta_header)) units.
Stuffed directories don't have an additional gfs2_meta_header, but the
stuffed case is handled separately for both files and directories,
anyway.
Remove the unncessary sdp->sd_jheightsize array.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Instead of zeroing out fallocated blocks in gfs2_iomap_alloc, zero them
out in fallocate_chunk, much higher up the call stack. This gets rid of
gfs2's abuse of the IOMAP_ZERO flag as well as the gfs2 specific zeronew
buffer flag. I can't think of a reason why zeroing out the blocks in
gfs2_iomap_alloc would have any benefits: there is no additional locking
at that level that would add protection to the newly allocated blocks.
While at it, change fallocate over from gs2_block_map to gfs2_iomap_begin.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Get rid of gfs2_log_header_in by integrating it into get_log_header.
Clean up the crc32 computations and use the same functions for encoding
and decoding to make things less confusing. Eliminate lh_hash from
gfs2_log_header_host which is completely useless.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Add a small inline function for computing the maximum size of a stuffed
inode instead of open coding that in several places throughout the code.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Enlarge sd_fsname to be big enough for the longest long lock table name
and an arbitrary journal number. This silences two -Wformat-truncation
warnings with gcc 7.1.1.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch, if GFS2 encountered IO errors while writing to
the journal, it would not report the problem, so they would go
unnoticed, sometimes for many hours. Sometimes this would only be
noticed later, when recovery tried to do journal replay and failed
due to invalid metadata at the blocks that resulted in IO errors.
This patch makes GFS2's log daemon check for IO errors. If it
encounters one, it withdraws from the file system and reports
why in dmesg. A similar action is taken when IO errors occur when
writing to the system statfs file.
These errors are also reported back to any callers of fsync, since
that requires the journal to be flushed. Therefore, any IO errors
that would previously go unnoticed are now noticed and the file
system is withdrawn as early as possible, thus preventing further
file system damage.
Also note that this reintroduces superblock variable sd_log_error,
which Christoph removed with commit f729b66fca.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
On systems with low memory, it is possible for gfs2 to infinitely
loop in balance_dirty_pages() under heavy IO (creating sparse files).
balance_dirty_pages() attempts to write out the dirty pages via
gfs2_writepages() but none are found because these dirty pages are
being used by the journaling code in the ail. Normally, the journal
has an upper threshold which when hit triggers an automatic flush
of the ail. But this threshold can be higher than the number of
allowable dirty pages and result in the ail never being flushed.
This patch forces an ail flush when gfs2_writepages() fails to write
anything. This is a good indication that the ail might be holding
some dirty pages.
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before commit 88ffbf3e03 "GFS2: Use resizable hash table for glocks",
glocks were freed via call_rcu to allow reading the glock hashtable
locklessly using rcu. This was then changed to free glocks immediately,
which made reading the glock hashtable unsafe. Bring back the original
code for freeing glocks via call_rcu.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Cc: stable@vger.kernel.org # 4.3+
1. Andreas Gruenbacher has four patches related to cleaning up the GFS2
inode evict process. This is about half of his patches designed to
fix a long-standing GFS2 hang related to the inode shrinker.
(Shrinker calls gfs2 evict, evict calls DLM, DLM requires memory
and blocks on the shrinker.) These 4 patches have been well tested.
His second set of patches are still being tested, so I plan to hold
them until the next merge window, after we have more weeks of testing.
The first patch eliminates the flush_delayed_work, which can block.
2. Andreas's second patch protects setting of gl_object for rgrps with
a spin_lock to prevent proven races.
3. His third patch introduces a centralized mechanism for queueing glock
work with better reference counting, to prevent more races.
4. His fourth patch retains a reference to inode glocks when an error
occurs while creating an inode. This keeps the subsequent evict from
needing to reacquire the glock, which might call into DLM and block
in low memory conditions.
5. Arvind Yadav has a patch to add const to attribute_group structures.
6. I have a patch to detect directory entry inconsistencies and withdraw
the file system if any are found. Better that than silent corruption.
7. I have a patch to remove a vestigial variable from glock structures,
saving some slab space.
8. I have another patch to remove a vestigial variable from the GFS2
in-core superblock structure.
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Merge tag 'gfs2-4.13.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull GFS2 updates from Bob Peterson:
"We've got eight GFS2 patches for this merge window:
- Andreas Gruenbacher has four patches related to cleaning up the
GFS2 inode evict process. This is about half of his patches
designed to fix a long-standing GFS2 hang related to the inode
shrinker: Shrinker calls gfs2 evict, evict calls DLM, DLM requires
memory and blocks on the shrinker.
These four patches have been well tested. His second set of patches
are still being tested, so I plan to hold them until the next merge
window, after we have more weeks of testing. The first patch
eliminates the flush_delayed_work, which can block.
- Andreas's second patch protects setting of gl_object for rgrps with
a spin_lock to prevent proven races.
- His third patch introduces a centralized mechanism for queueing
glock work with better reference counting, to prevent more races.
-His fourth patch retains a reference to inode glocks when an error
occurs while creating an inode. This keeps the subsequent evict
from needing to reacquire the glock, which might call into DLM and
block in low memory conditions.
- Arvind Yadav has a patch to add const to attribute_group
structures.
- I have a patch to detect directory entry inconsistencies and
withdraw the file system if any are found. Better that than silent
corruption.
- I have a patch to remove a vestigial variable from glock
structures, saving some slab space.
- I have another patch to remove a vestigial variable from the GFS2
in-core superblock structure"
* tag 'gfs2-4.13.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
GFS2: constify attribute_group structures.
gfs2: gfs2_create_inode: Keep glock across iput
gfs2: Clean up glock work enqueuing
gfs2: Protect gl->gl_object by spin lock
gfs2: Get rid of flush_delayed_work in gfs2_evict_inode
GFS2: Eliminate vestigial sd_log_flush_wrapped
GFS2: Remove gl_list from glock structure
GFS2: Withdraw when directory entry inconsistencies are detected
Put all remaining accesses to gl->gl_object under the
gl->gl_lockref.lock spinlock to prevent races.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
So far, gfs2_evict_inode clears gl->gl_object and then flushes the glock
work queue to make sure that inode glops which dereference gl->gl_object
have finished running before the inode is destroyed. However, flushing
the work queue may do more work than needed, and in particular, it may
call into DLM, which we want to avoid here. Use a bit lock
(GIF_GLOP_PENDING) to synchronize between the inode glops and
gfs2_evict_inode instead to get rid of the flushing.
In addition, flush the work queues of existing glocks before reusing
them for new inodes to get those glocks into a known state: the glock
state engine currently doesn't handle glock re-appropriation correctly.
(We may be able to fix the glock state engine instead later.)
Based on a patch by Steven Whitehouse <swhiteho@redhat.com>.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
As per a suggestion by Linus, don't pack struct lm_lockname: we did that
because the struct is used as a rhashtable key, but packing tells the
compiler that the 64-bit fields in the struct may be unaligned, causing
it to generate worse code on some architectures. Instead, rearrange the
fields in the struct so that there is no padding between fields, and
exclude any tail padding from the hash key size.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Commit 88ffbf3e03 switches to using rhashtables for glocks, hashing over
the entire struct lm_lockname instead of its individual fields. On some
architectures, struct lm_lockname contains a hole of uninitialized
memory due to alignment rules, which now leads to incorrect hash values.
Get rid of that hole.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
CC: <stable@vger.kernel.org> #v4.3+
This patch eliminates the int variable tr_touched in favor of a
new flag in the transaction. This is a step toward reducing contention
on the gfs2_log_lock spin_lock.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch, the logd daemon only tried to flush things when
the log blocks pinned exceeded a certain threshold. But when we're
deleting very large files, it may require a huge number of journal
blocks, and that, in turn, may exceed the threshold. This patch
factors that into account.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
This patch tries to prevent delete work (queued via iopen callback)
from executing if the glock is currently being used to create
a new inode.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
gfs2 currently returns 31 bits of filename hash as a cookie that readdir
uses for an offset into the directory. When there are a large number of
directory entries, the likelihood of a collision goes up way too
quickly. GFS2 will now return cookies that are guaranteed unique for a
while, and then fail back to using 30 bits of filename hash.
Specifically, the directory leaf blocks are divided up into chunks based
on the minimum size of a gfs2 directory entry (48 bytes). Each entry's
cookie is based off the chunk where it starts, in the linked list of
leaf blocks that it hashes to (there are 131072 hash buckets). Directory
entries will have unique names until they take reach chunk 8192.
Assuming the largest filenames possible, and the least efficient spacing
possible, this new method will still be able to return unique names when
the previous method has statistically more than a 99% chance of a
collision. The non-unique names it fails back to are guaranteed to not
collide with the unique names.
unique cookies will be in this format:
- 1 bit "0" to make sure the the returned cookie is positive
- 17 bits for the hash table index
- 1 bit for the mode "0"
- 13 bits for the offset
non-unique cookies will be in this format:
- 1 bit "0" to make sure the the returned cookie is positive
- 17 bits for the hash table index
- 1 bit for the mode "1"
- 13 more bits of the name hash
Another benefit of location based cookies, is that once a directory's
exhash table is fully extended (so that multiple hash table indexs do
not use the same leaf blocks), gfs2 can skip sorting the directory
entries until it reaches the non-unique ones, and then it only needs to
sort these. This provides a significant speed up for directory reads of
very large directories.
The only issue is that for these cookies to continue to point to the
correct entry as files are added and removed from the directory, gfs2
must keep the entries at the same offset in the leaf block when they are
split (see my previous patch). This means that until all the nodes in a
cluster are running with code that will split the directory leaf blocks
this way, none of the nodes can use the new cookie code. To deal with
this, gfs2 now has the mount option loccookie, which, if set, will make
it return these new location based cookies. This option must not be set
until all nodes in the cluster are at least running this version of the
kernel code, and you have guaranteed that there are no outstanding
cookies required by other software, such as NFS.
gfs2 uses some of the extra space at the end of the gfs2_dirent
structure to store the calculated readdir cookies. This keeps us from
needing to allocate a seperate array to hold these values. gfs2
recomputes the cookie stored in de_cookie for every readdir call. The
time it takes to do so is small, and if gfs2 expected this value to be
saved on disk, the new code wouldn't work correctly on filesystems
created with an earlier version of gfs2.
One issue with adding de_cookie to the union in the gfs2_dirent
structure is that it caused the union to align itself to a 4 byte
boundary, instead of its previous 2 byte boundary. This changed the
offset of de_rahead. To solve that, I pulled de_rahead out of the union,
since it does not need to be there.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
This patch makes no functional changes. Its goal is to reduce the
size of the gfs2 inode in memory by rearranging structures and
changing the size of some variables within the structure.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch, multi-block reservation structures were allocated
from a special slab. This patch folds the structure into the gfs2_inode
structure. The disadvantage is that the gfs2_inode needs more memory,
even when a file is opened read-only. The advantages are: (a) we don't
need the special slab and the extra time it takes to allocate and
deallocate from it. (b) we no longer need to worry that the structure
exists for things like quota management. (c) This also allows us to
remove the calls to get_write_access and put_write_access since we
know the structure will exist.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
This patch basically reverts the majority of patch 5407e24.
That patch eliminated the gfs2_qadata structure in favor of just
using the reservations structure. The problem with doing that is that
it increases the size of the reservations structure. That is not an
issue until it comes time to fold the reservations structure into the
inode in memory so we know it's always there. By separating out the
quota structure again, we aren't punishing the non-quota users by
making all the inodes bigger, requiring more slab space. This patch
creates a new slab area to allocate the quota stuff so it's managed
a little more sanely.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
When gfs2 allocates an inode and its extended attribute block next to
each other at inode create time, the inode's directory entry indicates
that in de_rahead. In that case, we can readahead the extended
attribute block when we read in the inode.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Commit e66cf161 replaced the gl_spin spinlock in struct gfs2_glock with a
gl_lockref lockref and defined gl_spin as gl_lockref.lock (the spinlock in
gl_lockref). Remove that define to make the references to gl_lockref.lock more
obvious.
Signed-off-by: Andreas Gruenbacher <andreas.gruenbacher@gmail.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
None of these statistics can meaningfully be negative, and the
numerator for do_div() must have the type u64. The generic
implementation of do_div() used on some 32-bit architectures asserts
that, resulting in a compiler error in gfs2_rgrp_congested().
Fixes: 0166b197c2 ("GFS2: Average in only non-zero round-trip times ...")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch changes the glock hash table from a normal hash table to
a resizable hash table, which scales better. This also simplifies
a lot of code.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
What uniquely identifies a glock in the glock hash table is not
gl_name, but gl_name and its superblock pointer. This patch makes
the gl_name field correspond to a unique glock identifier. That will
allow us to simplify hashing with a future patch, since the hash
algorithm can then take the gl_name and hash its components in one
operation.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
The glocks used for resource groups often come and go hundreds of
thousands of times per second. Adding them to the lru list just
adds unnecessary contention for the lru_lock spin_lock, especially
considering we're almost certainly going to re-use the glock and
take it back off the lru microseconds later. We never want the
glock shrinker to cull them anyway. This patch adds a new bit in
the glops that determines which glock types get put onto the lru
list and which ones don't.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
This patch makes the quota subsystem only report once that a
particular user/group has exceeded their allotted quota.
Previously, it was possible for a program to continuously try
exceeding quota (despite receiving EDQUOT) and in turn trigger
gfs2 to issue a kernel log message about quota exceed. In theory,
this could get out of hand and flood the log and the filesystem
hosting the log files.
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
struct gfs2_alloc_parms is passed to gfs2_quota_check() and
gfs2_inplace_reserve() with ap->target containing the number of
blocks being requested for allocation in the current operation.
We add a new field to struct gfs2_alloc_parms called 'allowed'.
gfs2_quota_check() and gfs2_inplace_reserve() return the max
blocks allowed by quota and the max blocks allowed by the chosen
rgrp respectively in 'allowed'.
A new field 'min_target', when non-zero, tells gfs2_quota_check()
and gfs2_inplace_reserve() to not return -EDQUOT/-ENOSPC when
there are atleast 'min_target' blocks allowable/available. The
assumption is that the caller is ok with just 'min_target' blocks
and will likely proceed with allocating them.
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Use struct gfs2_alloc_parms as an argument to gfs2_quota_check()
and gfs2_quota_lock_check() to check for quota violations while
accounting for the new blocks requested by the current operation
in ap->target.
Previously, the number of new blocks requested during an operation
were not accounted for during quota_check and would allow these
operations to exceed quota. This was not very apparent since most
operations allocated only 1 block at a time and quotas would get
violated in the next operation. i.e. quota excess would only be by
1 block or so. With fallocate, (where we allocate a bunch of blocks
at once) the quota excess is non-trivial and is addressed by this
patch.
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
The current gfs2 freezing code is considerably more complicated than it
should be because it doesn't use the vfs freezing code on any node except
the one that begins the freeze. This is because it needs to acquire a
cluster glock before calling the vfs code to prevent a deadlock, and
without the new freeze_super and thaw_super hooks, that was impossible. To
deal with the issue, gfs2 had to do some hacky locking tricks to make sure
that a frozen node couldn't be holding on a lock it needed to do the
unfreeze ioctl.
This patch makes use of the new hooks to simply the gfs2 locking code. Now,
all the nodes in the cluster freeze and thaw in exactly the same way. Every
node in the cluster caches the freeze glock in the shared state. The new
freeze_super hook allows the freezing node to grab this freeze glock in
the exclusive state without first calling the vfs freeze_super function.
All the nodes in the cluster see this lock change, and call the vfs
freeze_super function. The vfs locking code guarantees that the nodes can't
get stuck holding the glocks necessary to unfreeze the system. To
unfreeze, the freezing node uses the new thaw_super hook to drop the freeze
glock. Again, all the nodes notice this, reacquire the glock in shared mode
and call the vfs thaw_super function.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch tries to use the journal numbers to evenly distribute
which node prefers which resource group for block allocations. This
is to help performance.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
MAXQUOTAS value defines maximum number of quota types VFS supports.
This isn't necessarily the number of types gfs2 supports and with
addition of project quotas these two numbers stop matching. So make gfs2
use its private definition.
CC: cluster-devel@redhat.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch uses a completion to prevent dlm's recovery process from
referencing and trying to recover a journal before a journal has been
opened.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
GFS2 has a transaction glock, which must be grabbed for every
transaction, whose purpose is to deal with freezing the filesystem.
Aside from this involving a large amount of locking, it is very easy to
make the current fsfreeze code hang on unfreezing.
This patch rewrites how gfs2 handles freezing the filesystem. The
transaction glock is removed. In it's place is a freeze glock, which is
cached (but not held) in a shared state by every node in the cluster
when the filesystem is mounted. This lock only needs to be grabbed on
freezing, and actions which need to be safe from freezing, like
recovery.
When a node wants to freeze the filesystem, it grabs this glock
exclusively. When the freeze glock state changes on the nodes (either
from shared to unlocked, or shared to exclusive), the filesystem does a
special log flush. gfs2_log_flush() does all the work for flushing out
the and shutting down the incore log, and then it tries to grab the
freeze glock in a shared state again. Since the filesystem is stuck in
gfs2_log_flush, no new transaction can start, and nothing can be written
to disk. Unfreezing the filesytem simply involes dropping the freeze
glock, allowing gfs2_log_flush() to grab and then release the shared
lock, so it is cached for next time.
However, in order for the unfreezing ioctl to occur, gfs2 needs to get a
shared lock on the filesystem root directory inode to check permissions.
If that glock has already been grabbed exclusively, fsfreeze will be
unable to get the shared lock and unfreeze the filesystem.
In order to allow the unfreeze, this patch makes gfs2 grab a shared lock
on the filesystem root directory during the freeze, and hold it until it
unfreezes the filesystem. The functions which need to grab a shared
lock in order to allow the unfreeze ioctl to be issued now use the lock
grabbed by the freeze code instead.
The freeze and unfreeze code take care to make sure that this shared
lock will not be dropped while another process is using it.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When gfs2_create_inode() fails due to quota violation, the VFS
inode is not completely uninitialized. This can cause a list
corruption error.
This patch correctly uninitializes the VFS inode when a quota
violation occurs in the gfs2_create_inode codepath.
Resolves: rhbz#1059808
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
If multiple nodes fail and their recovery work runs simultaneously, they
would use the same unprotected variables in the superblock. For example,
they would stomp on each other's revoked blocks lists, which resulted
in file system metadata corruption. This patch moves the necessary
variables so that each journal has its own separate area for tracking
its journal replay.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes a long standing issue in mapping the journal
extents. Most journals will consist of only a single extent,
and although the cache took account of that by merging extents,
it did not actually map large extents, but instead was doing a
block by block mapping. Since the journal was only being mapped
on mount, this was not normally noticeable.
With the updated code, it is now possible to use the same extent
mapping system during journal recovery (which will be added in a
later patch). This will allow checking of the integrity of the
journal before any reply of the journal content is attempted. For
this reason the code is moving to bmap.c, since it will be used
more widely in due course.
An exercise left for the reader is to compare the new function
gfs2_map_journal_extents() with gfs2_write_alloc_required()
Additionally, should there be a failure, the error reporting is
also updated to show more detail about what went wrong.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Now we have a master transaction into which other transactions
are merged, the accounting can be done using this master
transaction. We no longer require the superblock fields which
were being used for this function.
In addition, this allows for a clean up in calc_reserved()
making it rather easier understand. Also, by reducing the
number of variables used to track the buffers being added
and removed from the journal, a number of error checks are
now no longer required.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
