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* Merge branch 'master' of ↵Linus Torvalds2010-04-121-5/+15
|\ | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: make sure the chunk allocator doesn't create zero length chunks Btrfs: fix data enospc check overflow
| * Btrfs: fix data enospc check overflowJosef Bacik2010-04-051-5/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because we account for reserved space we get from the allocator before we actually account for allocating delalloc space, we can have a small window where the amount of "used" space in a space_info is more than the total amount of space in the space_info. This will cause a overflow in our check, so it will seem like we have _tons_ of free space, and we'll allow reservations to occur that will end up larger than the amount of space we have. I've seen users report ENOSPC panic's in cow_file_range a few times recently, so I tried to reproduce this problem and found I could reproduce it if I ran one of my tests in a loop for like 20 minutes. With this patch my test ran all night without issues. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstableLinus Torvalds2010-04-051-9/+14
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: add check for changed leaves in setup_leaf_for_split Btrfs: create snapshot references in same commit as snapshot Btrfs: fix small race with delalloc flushing waitqueue's Btrfs: use add_to_page_cache_lru, use __page_cache_alloc Btrfs: fix chunk allocate size calculation Btrfs: kill max_extent mount option Btrfs: fail to mount if we have problems reading the block groups Btrfs: check btrfs_get_extent return for IS_ERR() Btrfs: handle kmalloc() failure in inode lookup ioctl Btrfs: dereferencing freed memory Btrfs: Simplify num_stripes's calculation logical for __btrfs_alloc_chunk() Btrfs: Add error handle for btrfs_search_slot() in btrfs_read_chunk_tree() Btrfs: Remove unnecessary finish_wait() in wait_current_trans() Btrfs: add NULL check for do_walk_down() Btrfs: remove duplicate include in ioctl.c Fix trivial conflict in fs/btrfs/compression.c due to slab.h include cleanups.
| * Btrfs: fix small race with delalloc flushing waitqueue'sJosef Bacik2010-04-051-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Everytime we start a new flushing thread, we init the waitqueue if there isn't a flushing thread running. The problem with this is we check space_info->flushing, which we clear right before doing a wake_up on the flushing waitqueue, which causes problems if we init the waitqueue in the middle of clearing the flushing flagh and calling wake_up. This is hard to hit, but the code is wrong anyway, so init the flushing/allocating waitqueue when creating the space info and let it be. I haven't seen the panic since I've been using this patch. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: kill max_extent mount optionJosef Bacik2010-03-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | As Yan pointed out, theres not much reason for all this complicated math to account for file extents being split up into max_extent chunks, since they are likely to all end up in the same leaf anyway. Since there isn't much reason to use max_extent, just remove the option altogether so we have one less thing we need to test. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: fail to mount if we have problems reading the block groupsJosef Bacik2010-03-301-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't actually check the return value of btrfs_read_block_groups, so we can possibly succeed to mount, but then fail to say read the superblock xattr for selinux which will cause the vfs code to deactivate the super. This is a problem because in find_free_extent we just assume that we will find the right space_info for the allocation we want. But if we failed to read the block groups, we won't have setup any space_info's, and we'll hit a NULL pointer deref in find_free_extent. This patch fixes that problem by checking the return value of btrfs_read_block_groups, and failing out properly. I've also added a check in find_free_extent so if for some reason we don't find an appropriate space_info, we just return -ENOSPC. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: add NULL check for do_walk_down()Miao Xie2010-03-301-1/+4
| | | | | | | | | | | | | | | | btrfs_find_create_tree_block() may return NULL, so we must check the returned value, or we will access a NULL pointer. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* Btrfs: cache the extent state everywhere we possibly can V2Josef Bacik2010-03-151-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch just goes through and fixes everybody that does lock_extent() blah unlock_extent() to use lock_extent_bits() blah unlock_extent_cached() and pass around a extent_state so we only have to do the searches once per function. This gives me about a 3 mb/s boots on my random write test. I have not converted some things, like the relocation and ioctl's, since they aren't heavily used and the relocation stuff is in the middle of being re-written. I also changed the clear_extent_bit() to only unset the cached state if we are clearing EXTENT_LOCKED and related stuff, so we can do things like this lock_extent_bits() clear delalloc bits unlock_extent_cached() without losing our cached state. I tested this thoroughly and turned on LEAK_DEBUG to make sure we weren't leaking extent states, everything worked out fine. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: Fix oopsen when dropping empty tree.Yan, Zheng2010-02-041-4/+4
| | | | | | | | | When dropping a empty tree, walk_down_tree() skips checking extent information for the tree root. This will triggers a BUG_ON in walk_up_proc(). Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: fix possible panic on unmountJosef Bacik2010-01-171-13/+19
| | | | | | | | | | | | | We can race with the unmount of an fs and the stopping of a kthread where we will free the block group before we're done using it. The reason for this is because we do not hold a reference on the block group while its caching, since the allocator drops its reference once it exits or moves on to the next block group. This patch fixes the problem by taking a reference to the block group before we start caching and dropping it when we're done to make sure all accesses to the block group are safe. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: make metadata chunks smallerJosef Bacik2009-12-171-10/+1
| | | | | | | | | | | | This patch makes us a bit less zealous about making sure we have enough free metadata space by pearing down the size of new metadata chunks to 256mb instead of 1gb. Also, we used to try an allocate metadata chunks when allocating data, but that sort of thing is done elsewhere now so we can just remove it. With my -ENOSPC test I used to have 3gb reserved for metadata out of 75gb, now I have 1.7gb. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: don't add extent 0 to the free space cache v2Yan, Zheng2009-12-171-1/+9
| | | | | | | | If block group 0 is completely free, btrfs_read_block_groups will add extent [0, BTRFS_SUPER_INFO_OFFSET) to the free space cache. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: Fix per root used space accountingYan, Zheng2009-12-171-8/+23
| | | | | | | | | | The bytes_used field in root item was originally planned to trace the amount of used data and tree blocks. But it never worked right since we can't trace freeing of data accurately. This patch changes it to only trace the amount of tree blocks. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: Add delayed iputYan, Zheng2009-12-171-4/+4
| | | | | | | | | | iput() can trigger new transactions if we are dropping the final reference, so calling it in btrfs_commit_transaction may end up deadlock. This patch adds delayed iput to avoid the issue. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: Avoid superfluous tree-log writeoutYan, Zheng2009-12-151-2/+10
| | | | | | | | | | | We allow two log transactions at a time, but use same flag to mark dirty tree-log btree blocks. So we may flush dirty blocks belonging to newer log transaction when committing a log transaction. This patch fixes the issue by using two flags to mark dirty tree-log btree blocks. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstableLinus Torvalds2009-11-111-25/+88
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: fix panic when trying to destroy a newly allocated Btrfs: allow more metadata chunk preallocation Btrfs: fallback on uncompressed io if compressed io fails Btrfs: find ideal block group for caching Btrfs: avoid null deref in unpin_extent_cache() Btrfs: skip btrfs_release_path in btrfs_update_root and btrfs_del_root Btrfs: fix some metadata enospc issues Btrfs: fix how we set max_size for free space clusters Btrfs: cleanup transaction starting and fix journal_info usage Btrfs: fix data allocation hint start
| * Btrfs: allow more metadata chunk preallocationChris Mason2009-11-111-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On an FS where all of the space has not been allocated into chunks yet, the enospc can return enospc just because the existing metadata chunks are full. We get around this by allowing more metadata chunks to be allocated up to a certain limit, and finding the right limit is a little fuzzy. The problem is the reservations for delalloc would preallocate way too much of the FS as metadata. We need to start saying no and just force some IO to happen. But we also need to let a reasonable amount of the FS become metadata. This bumps the hard limit up, later releases will have a better system. Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: find ideal block group for cachingJosef Bacik2009-11-111-23/+86
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch changes a few things. Hopefully the comments are helpfull, but I'll try and be as verbose here. Problem: My fedora box was taking 1 minute and 21 seconds to boot with btrfs as root. Part of this problem was we pick the first block group we can find and start caching it, even if it may not have enough free space. The other problem is we only search for cached block groups the first time around, which we won't find any cached block groups because this is a newly mounted fs, so we end up caching several block groups during bootup, which with alot of fragmentation takes around 30-45 seconds to complete, which bogs down the system. So Solution: 1) Don't cache block groups willy-nilly at first. Instead try and figure out which block group has the most free, and therefore will take the least amount of time to cache. 2) Don't be so picky about cached block groups. The other problem is once we've filled up a cluster, if the block group isn't finished caching the next time we try and do the allocation we'll completely ignore the cluster and start searching from the beginning of the space, which makes us cache more block groups, which slows us down even more. So instead of skipping block groups that are not finished caching when we have a hint, only skip the block group if it hasn't started caching yet. There is one other tweak in here. Before if we allocated a chunk and still couldn't find new space, we'd end up switching the space info to force another chunk allocation. This could make us end up with way too many chunks, so keep track of this particular case. With this patch and my previous cluster fixes my fedora box now boots in 43 seconds, and according to the bootchart is not held up by our block group caching at all. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | Merge branch 'master' of ↵Linus Torvalds2009-10-151-6/+11
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: always pin metadata in discard mode Btrfs: enable discard support Btrfs: add -o discard option Btrfs: properly wait log writers during log sync Btrfs: fix possible ENOSPC problems with truncate Btrfs: fix btrfs acl #ifdef checks Btrfs: streamline tree-log btree block writeout Btrfs: avoid tree log commit when there are no changes Btrfs: only write one super copy during fsync
| * Btrfs: always pin metadata in discard modeChris Mason2009-10-141-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | We have an optimization in btrfs to allow blocks to be immediately freed if they were allocated in this transaction and never written. Otherwise they are pinned and freed when the transaction commits. This isn't optimal for discard mode because immediately freeing them means immediately discarding them. It is better to give the block to the pinning code and letting the (slow) discard happen later. Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: enable discard supportChristoph Hellwig2009-10-141-6/+0
| | | | | | | | | | | | | | | | | | The discard support code in btrfs currently is guarded by ifdefs for BIO_RW_DISCARD, which is never defines as it's the name of an enum memeber. Just remove the useless ifdefs to actually enable the code. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: add -o discard optionChristoph Hellwig2009-10-141-0/+3
| | | | | | | | | | | | | | | | | | | | Enable discard by default is not a good idea given the the trim speed of SSD prototypes we've seen, and the carecteristics for many high-end arrays. Turn of discards by default and require the -o discard option to enable them on. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstableLinus Torvalds2009-10-111-49/+186
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: fix file clone ioctl for bookend extents Btrfs: fix uninit compiler warning in cow_file_range_nocow Btrfs: constify dentry_operations Btrfs: optimize back reference update during btrfs_drop_snapshot Btrfs: remove negative dentry when deleting subvolumne Btrfs: optimize fsync for the single writer case Btrfs: async delalloc flushing under space pressure Btrfs: release delalloc reservations on extent item insertion Btrfs: delay clearing EXTENT_DELALLOC for compressed extents Btrfs: cleanup extent_clear_unlock_delalloc flags Btrfs: fix possible softlockup in the allocator Btrfs: fix deadlock on async thread startup
| * Btrfs: optimize back reference update during btrfs_drop_snapshotYan, Zheng2009-10-091-29/+53
| | | | | | | | | | | | | | This patch reading level 0 tree blocks that already use full backrefs. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: async delalloc flushing under space pressureJosef Bacik2009-10-081-5/+75
| | | | | | | | | | | | | | | | | | | | | | | | This patch moves the delalloc flushing that occurs when we are under space pressure off to a async thread pool. This helps since we only free up metadata space when we actually insert the extent item, which means it takes quite a while for space to be free'ed up if we wait on all ordered extents. However, if space is freed up due to inline extents being inserted, we can wake people who are waiting up early, and they can finish their work. Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: release delalloc reservations on extent item insertionJosef Bacik2009-10-081-11/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes an issue with the delalloc metadata space reservation code. The problem is we used to free the reservation as soon as we allocated the delalloc region. The problem with this is if we are not inserting an inline extent, we don't actually insert the extent item until after the ordered extent is written out. This patch does 3 things, 1) It moves the reservation clearing stuff into the ordered code, so when we remove the ordered extent we remove the reservation. 2) It adds a EXTENT_DO_ACCOUNTING flag that gets passed when we clear delalloc bits in the cases where we want to clear the metadata reservation when we clear the delalloc extent, in the case that we do an inline extent or we invalidate the page. 3) It adds another waitqueue to the space info so that when we start a fs wide delalloc flush, anybody else who also hits that area will simply wait for the flush to finish and then try to make their allocation. This has been tested thoroughly to make sure we did not regress on performance. Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: fix possible softlockup in the allocatorJosef Bacik2009-10-061-6/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Like the cluster allocating stuff, we can lockup the box with the normal allocation path. This happens when we 1) Start to cache a block group that is severely fragmented, but has a decent amount of free space. 2) Start to commit a transaction 3) Have the commit try and empty out some of the delalloc inodes with extents that are relatively large. The inodes will not be able to make the allocations because they will ask for allocations larger than a contiguous area in the free space cache. So we will wait for more progress to be made on the block group, but since we're in a commit the caching kthread won't make any more progress and it already has enough free space that wait_block_group_cache_progress will just return. So, if we wait and fail to make the allocation the next time around, just loop and go to the next block group. This keeps us from getting stuck in a softlockup. Thanks, Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | Merge branch 'master' of ↵Chris Mason2009-10-011-49/+342
|\ \ | |/ | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable into for-linus
| * Btrfs: fix deadlock with free space handling and user transactionsSage Weil2009-09-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | If an ioctl-initiated transaction is open, we can't force a commit during the free space checks in order to free up pinned extents or else we deadlock. Just ENOSPC instead. A more satisfying solution that reserves space for the entire user transaction up front is forthcoming... Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: proper -ENOSPC handlingJosef Bacik2009-09-281-48/+341
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At the start of a transaction we do a btrfs_reserve_metadata_space() and specify how many items we plan on modifying. Then once we've done our modifications and such, just call btrfs_unreserve_metadata_space() for the same number of items we reserved. For keeping track of metadata needed for data I've had to add an extent_io op for when we merge extents. This lets us track space properly when we are doing sequential writes, so we don't end up reserving way more metadata space than what we need. The only place where the metadata space accounting is not done is in the relocation code. This is because Yan is going to be reworking that code in the near future, so running btrfs-vol -b could still possibly result in a ENOSPC related panic. This patch also turns off the metadata_ratio stuff in order to allow users to more efficiently use their disk space. This patch makes it so we track how much metadata we need for an inode's delayed allocation extents by tracking how many extents are currently waiting for allocation. It introduces two new callbacks for the extent_io tree's, merge_extent_hook and split_extent_hook. These help us keep track of when we merge delalloc extents together and split them up. Reservations are handled prior to any actually dirty'ing occurs, and then we unreserve after we dirty. btrfs_unreserve_metadata_for_delalloc() will make the appropriate unreservations as needed based on the number of reservations we currently have and the number of extents we currently have. Doing the reservation outside of doing any of the actual dirty'ing lets us do things like filemap_flush() the inode to try and force delalloc to happen, or as a last resort actually start allocation on all delalloc inodes in the fs. This has survived dbench, fs_mark and an fsx torture test. Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | Merge branch 'master' of ↵Chris Mason2009-09-241-979/+683
|\ \ | |/ | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable into for-linus Conflicts: fs/btrfs/super.c
| * Btrfs: fix early enospc during balancingChris Mason2009-09-221-13/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now do extra checks before a balance to make sure there is room for the balance to take place. One of the checks was testing to see if we were trying to balance away the last block group of a given type. If there is no space available for new chunks, we should not try and balance away the last block group of a give type. But, the code wasn't checking for available chunk space, and so it was exiting too soon. The fix here is to combine some of the checks and make sure we try to allocate new chunks when we're balancing the last block group. Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: deal with NULL space infoChris Mason2009-09-221-2/+16
| | | | | | | | | | | | | | | | | | After a balance it is briefly possible for the space info field in the inode to be NULL. This adds some checks to make sure things properly deal with the NULL value. Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: account for space used by the super mirrorsJosef Bacik2009-09-211-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | As we get closer to proper -ENOSPC handling in btrfs, we need more accurate space accounting for the space info's. Currently we exclude the free space for the super mirrors, but the space they take up isn't accounted for in any of the counters. This patch introduces bytes_super, which keeps track of the amount of bytes used for a super mirror in the block group cache and space info. This makes sure that our free space caclucations will be completely accurate. Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: remove dead codeJosef Bacik2009-09-211-706/+0
| | | | | | | | | | | | | | | | This patch removes a bunch of dead code from the snapshot removal stuff. It was confusing me when doing the metadata ENOSPC stuff so I killed it. Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: don't keep retrying a block group if we fail to allocate a clusterJosef Bacik2009-09-211-8/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The box can get locked up in the allocator if we happen upon a block group under these conditions: 1) During a commit, so caching threads cannot make progress 2) Our block group currently is in the middle of being cached 3) Our block group currently has plenty of free space in it 4) Our block group is so fragmented that it ends up having no free space chunks larger than min_bytes calculated by btrfs_find_space_cluster. What happens is we try and do btrfs_find_space_cluster, which fails because it is unable to find enough free space chunks that are large than min_bytes and are close enough together. Since the block group is not cached we do a wait_block_group_cache_progress, which waits for the number of bytes we need, except the block group already has _plenty_ of free space, its just severely fragmented, so we loop and try again, ad infinitum. This patch keeps us from waiting on the block group to finish caching if we failed to find a free space cluster before. It also makes sure that we don't even try to find a free space cluster if we are on our last loop in the allocator, since we will have tried everything at this point at it is futile. Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: make balance code choose more wisely when relocatingJosef Bacik2009-09-211-0/+87
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we can panic the box if the first block group we go to move is of a type where there is no space left to move those extents. For example, if we fill the disk up with data, and then we try to balance and we have no room to move the data nor room to allocate new chunks, we will panic. Change this by checking to see if we have room to move this chunk around, and if not, return -ENOSPC and move on to the next chunk. This will make sure we remove block groups that are moveable, like if we have alot of empty metadata block groups, and then that way we make room to be able to balance our data chunks as well. Tested this with an fs that would panic on btrfs-vol -b normally, but no longer panics with this patch. V1->V2: -actually search for a free extent on the device to make sure we can allocate a chunk if need be. -fix btrfs_shrink_device to make sure we actually try to relocate all the chunks, and then if we can't return -ENOSPC so if we are doing a btrfs-vol -r we don't remove the device with data still on it. -check to make sure the block group we are going to relocate isn't the last one in that particular space -fix a bug in btrfs_shrink_device where we would change the device's size and not fix it if we fail to do our relocate Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: add snapshot/subvolume destroy ioctlYan, Zheng2009-09-211-3/+18
| | | | | | | | | | | | | | | | This patch adds snapshot/subvolume destroy ioctl. A subvolume that isn't being used and doesn't contains links to other subvolumes can be destroyed. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: speed up snapshot droppingYan, Zheng2009-09-211-48/+205
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch contains two changes to avoid unnecessary tree block reads during snapshot dropping. First, check tree block's reference count and flags before reading the tree block. if reference count > 1 and there is no need to update backrefs, we can avoid reading the tree block. Second, save when snapshot was created in root_key.offset. we can compare block pointer's generation with snapshot's creation generation during updating backrefs. If a given block was created before snapshot was created, the snapshot can't be the tree block's owner. So we can avoid reading the block. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: improve async block group cachingYan Zheng2009-09-171-234/+352
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch gets rid of two limitations of async block group caching. The old code delays handling pinned extents when block group is in caching. To allocate logged file extents, the old code need wait until block group is fully cached. To get rid of the limitations, This patch introduces a data structure to track the progress of caching. Base on the caching progress, we know which extents should be added to the free space cache when handling the pinned extents. The logged file extents are also handled in a similar way. This patch also changes how pinned extents are tracked. The old code uses one tree to track pinned extents, and copy the pinned extents tree at transaction commit time. This patch makes it use two trees to track pinned extents. One tree for extents that are pinned in the running transaction, one tree for extents that can be unpinned. At transaction commit time, we swap the two trees. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: switch extent_map to a rw lockChris Mason2009-09-111-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | There are two main users of the extent_map tree. The first is regular file inodes, where it is evenly spread between readers and writers. The second is the chunk allocation tree, which maps blocks from logical addresses to phyiscal ones, and it is 99.99% reads. The mapping tree is a point of lock contention during heavy IO workloads, so this commit switches things to a rw lock. Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | block: use blkdev_issue_discard in blk_ioctl_discardChristoph Hellwig2009-09-141-1/+2
|/ | | | | | | | | | | | | | | blk_ioctl_discard duplicates large amounts of code from blkdev_issue_discard, the only difference between the two is that blkdev_issue_discard needs to send a barrier discard request and blk_ioctl_discard a non-barrier one, and blk_ioctl_discard needs to wait on the request. To facilitates this add a flags argument to blkdev_issue_discard to control both aspects of the behaviour. This will be very useful later on for using the waiting funcitonality for other callers. Based on an earlier patch from Matthew Wilcox <matthew@wil.cx>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Btrfs: make sure the async caching thread advances the keyChris Mason2009-07-311-4/+17
| | | | | | | | | | | | | | | | | The async caching thread can end up looping forever if a given search puts it at the last key in a leaf. It will end up calling btrfs_next_leaf and then checking if it needs to politely drop the read semaphore. Most of the time this looping isn't noticed because it is able to make progress the next time around. But, during log replay, we wait on the async caching thread to finish, and the async thread is waiting on the commit, and no progress is really made. The fix used here is to copy the key out of the next leaf, that way our search lands there properly. Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: be more polite in the async caching threadsChris Mason2009-07-301-2/+3
| | | | | | | | | The semaphore used by the async caching threads can prevent a transaction commit, which can make the FS appear to stall. This releases the semaphore more often when a transaction commit is in progress. Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: preserve commit_root for async cachingYan Zheng2009-07-301-3/+3
| | | | | | | | | | | | | | | | | | | The async block group caching code uses the commit_root pointer to get a stable version of the extent allocation tree for scanning. This copy of the tree root isn't going to change and it significantly reduces the complexity of the scanning code. During a commit, we have a loop where we update the extent allocation tree root. We need to loop because updating the root pointer in the tree of tree roots may allocate blocks which may change the extent allocation tree. Right now the commit_root pointer is changed inside this loop. It is more correct to change the commit_root pointer only after all the looping is done. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: Fix async caching interaction with unmountYan Zheng2009-07-281-1/+3
| | | | | | | | | | - don't stop the caching thread until btrfs_commit_super return. - if caching is interrupted by umount, set last to (u64)-1. otherwise the un-scanned range of block group will be considered as free extent. Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: change how we unpin extentsJosef Bacik2009-07-271-107/+42
| | | | | | | | | | | | | | | | | | | | | | | We are racy with async block caching and unpinning extents. This patch makes things much less complicated by only unpinning the extent if the block group is cached. We check the block_group->cached var under the block_group->lock spin lock. If it is set to BTRFS_CACHE_FINISHED then we update the pinned counters, and unpin the extent and add the free space back. If it is not set to this, we start the caching of the block group so the next time we unpin extents we can unpin the extent. This keeps us from racing with the async caching threads, lets us kill the fs wide async thread counter, and keeps us from having to set DELALLOC bits for every extent we hit if there are caching kthreads going. One thing that needed to be changed was btrfs_free_super_mirror_extents. Now instead of just looking for LOCKED extents, we also look for DIRTY extents, since we could have left some extents pinned in the previous transaction that will never get freed now that we are unmounting, which would cause us to leak memory. So btrfs_free_super_mirror_extents has been changed to btrfs_free_pinned_extents, and it will clear the extents locked for the super mirror, and any remaining pinned extents that may be present. Thank you, Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: clear all space_info->full after removing a block groupChris Mason2009-07-241-1/+2
| | | | | | | | | | | | | | | | | | | | Btrfs allocates individual extents from block groups, and each block group has a specific type. It may hold metadata, data mirrored or striped etc. When we balance space (btrfs-vol -b) or remove a drive (btrfs-vol -r) we free block groups. Once a block group is freed, the space it was using on the device may be available for use by new block groups. btrfs_remove_block_group was clearing the flag that said 'our devices are full, don't even try to allocate new block groups', but it was only clearing that flag for a specific type of block group. This commit clears the full flag for all of the types of block groups, making it much more likely that we'll be able to balance space when the drive is close to full. Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: async block group cachingJosef Bacik2009-07-241-91/+380
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch moves the caching of the block group off to a kthread in order to allow people to allocate sooner. Instead of blocking up behind the caching mutex, we instead kick of the caching kthread, and then attempt to make an allocation. If we cannot, we wait on the block groups caching waitqueue, which the caching kthread will wake the waiting threads up everytime it finds 2 meg worth of space, and then again when its finished caching. This is how I tested the speedup from this mkfs the disk mount the disk fill the disk up with fs_mark unmount the disk mount the disk time touch /mnt/foo Without my changes this took 11 seconds on my box, with these changes it now takes 1 second. Another change thats been put in place is we lock the super mirror's in the pinned extent map in order to keep us from adding that stuff as free space when caching the block group. This doesn't really change anything else as far as the pinned extent map is concerned, since for actual pinned extents we use EXTENT_DIRTY, but it does mean that when we unmount we have to go in and unlock those extents to keep from leaking memory. I've also added a check where when we are reading block groups from disk, if the amount of space used == the size of the block group, we go ahead and mark the block group as cached. This drastically reduces the amount of time it takes to cache the block groups. Using the same test as above, except doing a dd to a file and then unmounting, it used to take 33 seconds to umount, now it takes 3 seconds. This version uses the commit_root in the caching kthread, and then keeps track of how many async caching threads are running at any given time so if one of the async threads is still running as we cross transactions we can wait until its finished before handling the pinned extents. Thank you, Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
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