Commit Graph

221 Commits

Author SHA1 Message Date
Chris Mason d397712bcc Btrfs: Fix checkpatch.pl warnings
There were many, most are fixed now.  struct-funcs.c generates some warnings
but these are bogus.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-01-05 21:25:51 -05:00
Yan Zheng 52c2617990 Btrfs: update directory's size when creating subvol/snapshot
Make sure directory's size properly updated when creating
subvol/snapshot.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2009-01-05 15:43:43 -05:00
Yan Zheng d2fb3437e4 Btrfs: fix leaking block group on balance
The block group structs are referenced in many different
places, and it's not safe to free while balancing.  So, those block
group structs were simply leaked instead.

This patch replaces the block group pointer in the inode with the starting byte
offset of the block group and adds reference counting to the block group
struct.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2008-12-11 16:30:39 -05:00
Yan Zheng a512bbf855 Btrfs: superblock duplication
This patch implements superblock duplication. Superblocks
are stored at offset 16K, 64M and 256G on every devices.
Spaces used by superblocks are preserved by the allocator,
which uses a reverse mapping function to find the logical
addresses that correspond to superblocks. Thank you,

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2008-12-08 16:46:26 -05:00
Sage Weil 6e3ad88729 Btrfs: remove unneeded total_trans
Remove unneeded debugging sanity check.  It gets corrupted anyway when
multiple btrfs file systems are mounted, throwing bad warnings along the
way.

Signed-off-by: Sage Weil <sage@newdream.net>
2008-12-02 06:36:10 -05:00
Chris Mason 105d931d48 Btrfs: switch back to wait_on_page_writeback to wait on metadata writes
The extent based waiting was using more CPU, and other fixes have helped
with the unplug storm problems.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-11-18 12:13:12 -05:00
Chris Mason 0660b5af3f Btrfs: Add backrefs and forward refs for subvols and snapshots
Subvols and snapshots can now be referenced from any point in the directory
tree.  We need to maintain back refs for them so we can find lost
subvols.

Forward refs are added so that we know all of the subvols and
snapshots referenced anywhere in the directory tree of a single subvol.  This
can be used to do recursive snapshotting (but they aren't yet) and it is
also used to detect and prevent directory loops when creating new snapshots.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-11-17 20:37:39 -05:00
Chris Mason 3394e1607e Btrfs: Give each subvol and snapshot their own anonymous devid
Each subvolume has its own private inode number space, and so we need
to fill in different device numbers for each subvolume to avoid confusing
applications.

This commit puts a struct super_block into struct btrfs_root so it can
call set_anon_super() and get a different device number generated for
each root.

btrfs_rename is changed to prevent renames across subvols.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-11-17 20:42:26 -05:00
Chris Mason 3de4586c52 Btrfs: Allow subvolumes and snapshots anywhere in the directory tree
Before, all snapshots and subvolumes lived in a single flat directory.  This
was awkward and confusing because the single flat directory was only writable
with the ioctls.

This commit changes the ioctls to create subvols and snapshots at any
point in the directory tree.  This requires making separate ioctls for
snapshot and subvol creation instead of a combining them into one.

The subvol ioctl does:

btrfsctl -S subvol_name parent_dir

After the ioctl is done subvol_name lives inside parent_dir.

The snapshot ioctl does:

btrfsctl -s path_for_snapshot root_to_snapshot

path_for_snapshot can be an absolute or relative path.  btrfsctl breaks it up
into directory and basename components.

root_to_snapshot can be any file or directory in the FS.  The snapshot
is taken of the entire root where that file lives.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-11-17 21:02:50 -05:00
Chris Mason 5f2cc086cc Btrfs: Avoid unplug storms during commit
While doing a commit, btrfs makes sure all the metadata blocks
were properly written to disk, calling wait_on_page_writeback for
each page.  This writeback happens after allowing another transaction
to start, so it competes for the disk with other processes in the FS.

If the page writeback bit is still set, each wait_on_page_writeback might
trigger an unplug, even though the page might be waiting for checksumming
to finish or might be waiting for the async work queue to submit the
bio.

This trades wait_on_page_writeback for waiting on the extent writeback
bits.  It won't trigger any unplugs and substantially improves performance
in a number of workloads.

This also changes the async bio submission to avoid requeueing if there
is only one device.  The requeue just wastes CPU time because there are
no other devices to service.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-11-07 18:22:45 -05:00
Yan Zheng 80ff385665 Btrfs: update nodatacow code v2
This patch simplifies the nodatacow checker. If all references
were created after the latest snapshot, then we can avoid COW
safely. This patch also updates run_delalloc_nocow to do more
fine-grained checking.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2008-10-30 14:20:02 -04:00
Chris Mason 87ef2bb46b Btrfs: prevent looping forever in finish_current_insert and del_pending_extents
finish_current_insert and del_pending_extents process extent tree modifications
that build up while we are changing the extent tree.  It is a confusing
bit of code that prevents recursion.

Both functions run through a list of pending operations and both funcs
add to the list of pending operations.  If you have two procs in either
one of them, they can end up looping forever making more work for each other.

This patch makes them walk forward through the list of pending changes instead
of always trying to process the entire list.  At transaction commit
time, we catch any changes that were left over.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-10-30 11:23:27 -04:00
Yan Zheng 84234f3a1f Btrfs: Add root tree pointer transaction ids
This patch adds transaction IDs to root tree pointers.
Transaction IDs in tree pointers are compared with the
generation numbers in block headers when reading root
blocks of trees. This can detect some types of IO errors.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2008-10-29 14:49:05 -04:00
Josef Bacik 2517920135 Btrfs: nuke fs wide allocation mutex V2
This patch removes the giant fs_info->alloc_mutex and replaces it with a bunch
of little locks.

There is now a pinned_mutex, which is used when messing with the pinned_extents
extent io tree, and the extent_ins_mutex which is used with the pending_del and
extent_ins extent io trees.

The locking for the extent tree stuff was inspired by a patch that Yan Zheng
wrote to fix a race condition, I cleaned it up some and changed the locking
around a little bit, but the idea remains the same.  Basically instead of
holding the extent_ins_mutex throughout the processing of an extent on the
extent_ins or pending_del trees, we just hold it while we're searching and when
we clear the bits on those trees, and lock the extent for the duration of the
operations on the extent.

Also to keep from getting hung up waiting to lock an extent, I've added a
try_lock_extent so if we cannot lock the extent, move on to the next one in the
tree and we'll come back to that one.  I have tested this heavily and it does
not appear to break anything.  This has to be applied on top of my
find_free_extent redo patch.

I tested this patch on top of Yan's space reblancing code and it worked fine.
The only thing that has changed since the last version is I pulled out all my
debugging stuff, apparently I forgot to run guilt refresh before I sent the
last patch out.  Thank you,

Signed-off-by: Josef Bacik <jbacik@redhat.com>
2008-10-29 14:49:05 -04:00
Yan Zheng f82d02d9d8 Btrfs: Improve space balancing code
This patch improves the space balancing code to keep more sharing
of tree blocks. The only case that breaks sharing of tree blocks is
data extents get fragmented during balancing. The main changes in
this patch are:

Add a 'drop sub-tree' function. This solves the problem in old code
that BTRFS_HEADER_FLAG_WRITTEN check breaks sharing of tree block.

Remove relocation mapping tree. Relocation mappings are stored in
struct btrfs_ref_path and updated dynamically during walking up/down
the reference path. This reduces CPU usage and simplifies code.

This patch also fixes a bug. Root items for reloc trees should be
updated in btrfs_free_reloc_root.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2008-10-29 14:49:05 -04:00
Chris Mason 30c43e2444 Btrfs: remove last_log_alloc allocator optimization
The tree logging code was trying to separate tree log allocations
from normal metadata allocations to improve writeback patterns during
an fsync.

But, the code was not effective and ended up just mixing tree log
blocks with regular metadata.  That seems to be working fairly well,
so the last_log_alloc code can be removed.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-10-03 12:24:01 -04:00
Chris Mason d352ac6814 Btrfs: add and improve comments
This improves the comments at the top of many functions.  It didn't
dive into the guts of functions because I was trying to
avoid merging problems with the new allocator and back reference work.

extent-tree.c and volumes.c were both skipped, and there is definitely
more work todo in cleaning and commenting the code.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-29 15:18:18 -04:00
Zheng Yan 1a40e23b95 Btrfs: update space balancing code
This patch updates the space balancing code to utilize the new
backref format.  Before, btrfs-vol -b would break any COW links
on data blocks or metadata.  This was slow and caused the amount
of space used to explode if a large number of snapshots were present.

The new code can keeps the sharing of all data extents and
most of the tree blocks.

To maintain the sharing of data extents, the space balance code uses
a seperate inode hold data extent pointers, then updates the references
to point to the new location.

To maintain the sharing of tree blocks, the space balance code uses
reloc trees to relocate tree blocks in reference counted roots.
There is one reloc tree for each subvol, and all reloc trees share
same root key objectid. Reloc trees are snapshots of the latest
committed roots of subvols (root->commit_root).

To relocate a tree block referenced by a subvol, there are two steps.
COW the block through subvol's reloc tree, then update block pointer in
the subvol to point to the new block. Since all reloc trees share
same root key objectid, doing special handing for tree blocks
owned by them is easy. Once a tree block has been COWed in one
reloc tree, we can use the resulting new block directly when the
same block is required to COW again through other reloc trees.
In this way, relocated tree blocks are shared between reloc trees,
so they are also shared between subvols.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-26 10:09:34 -04:00
Zheng Yan 5b21f2ed3f Btrfs: extent_map and data=ordered fixes for space balancing
* Add an EXTENT_BOUNDARY state bit to keep the writepage code
from merging data extents that are in the process of being
relocated.  This allows us to do accounting for them properly.

* The balancing code relocates data extents indepdent of the underlying
inode.  The extent_map code was modified to properly account for
things moving around (invalidating extent_map caches in the inode).

* Don't take the drop_mutex in the create_subvol ioctl.  It isn't
required.

* Fix walking of the ordered extent list to avoid races with sys_unlink

* Change the lock ordering rules.  Transaction start goes outside
the drop_mutex.  This allows btrfs_commit_transaction to directly
drop the relocation trees.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-26 10:05:38 -04:00
Zheng Yan e465768938 Btrfs: Add shared reference cache
Btrfs has a cache of reference counts in leaves, allowing it to
avoid reading tree leaves while deleting snapshots.  To reduce
contention with multiple subvolumes, this cache is private to each
subvolume.

This patch adds shared reference cache support. The new space
balancing code plays with multiple subvols at the same time, So
the old per-subvol reference cache is not well suited.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-26 10:04:53 -04:00
Chris Mason d0c803c404 Btrfs: Record dirty pages tree-log pages in an extent_io tree
This is the same way the transaction code makes sure that all the
other tree blocks are safely on disk.  There's an extent_io tree
for each root, and any blocks allocated to the tree logs are
recorded in that tree.

At tree-log sync, the extent_io tree is walked to flush down the
dirty pages and wait for them.

The main benefit is less time spent walking the tree log and skipping
clean pages, and getting sequential IO down to the drive.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:07 -04:00
Chris Mason 4bef084857 Btrfs: Tree logging fixes
* Pin down data blocks to prevent them from being reallocated like so:

trans 1: allocate file extent
trans 2: free file extent
trans 3: free file extent during old snapshot deletion
trans 3: allocate file extent to new file
trans 3: fsync new file

Before the tree logging code, this was legal because the fsync
would commit the transation that did the final data extent free
and the transaction that allocated the extent to the new file
at the same time.

With the tree logging code, the tree log subtransaction can commit
before the transaction that freed the extent.  If we crash,
we're left with two different files using the extent.

* Don't wait in start_transaction if log replay is going on.  This
avoids deadlocks from iput while we're cleaning up link counts in the
replay code.

* Don't deadlock in replay_one_name by trying to read an inode off
the disk while holding paths for the directory

* Hold the buffer lock while we mark a buffer as written.  This
closes a race where someone is changing a buffer while we write it.
They are supposed to mark it dirty again after they change it, but
this violates the cow rules.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:07 -04:00
Chris Mason e02119d5a7 Btrfs: Add a write ahead tree log to optimize synchronous operations
File syncs and directory syncs are optimized by copying their
items into a special (copy-on-write) log tree.  There is one log tree per
subvolume and the btrfs super block points to a tree of log tree roots.

After a crash, items are copied out of the log tree and back into the
subvolume.  See tree-log.c for all the details.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:07 -04:00
Chris Mason b64a2851ba Btrfs: Wait for async bio submissions to make some progress at queue time
Before, the btrfs bdi congestion function was used to test for too many
async bios.  This keeps that check to throttle pdflush, but also
adds a check while queuing bios.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:06 -04:00
Chris Mason 777e6bd706 Btrfs: Transaction commit: don't use filemap_fdatawait
After writing out all the remaining btree blocks in the transaction,
the commit code would use filemap_fdatawait to make sure it was all
on disk.  This means it would wait for blocks written by other procs
as well.

The new code walks the list of blocks for this transaction again
and waits only for those required by this transaction.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:06 -04:00
Yan Zheng 7ea394f119 Btrfs: Fix nodatacow for the new data=ordered mode
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:06 -04:00
Yan Zheng b48652c101 Btrfs: Various small fixes.
This trivial patch contains two locking fixes and a off by one fix.

---

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:06 -04:00
Sage Weil 9ca9ee09c1 Btrfs: fix ioctl-initiated transactions vs wait_current_trans()
Commit 597:466b27332893 (btrfs_start_transaction: wait for commits in
progress) breaks the transaction start/stop ioctls by making
btrfs_start_transaction conditionally wait for the next transaction to
start.  If an application artificially is holding a transaction open,
things deadlock.

This workaround maintains a count of open ioctl-initiated transactions in
fs_info, and avoids wait_current_trans() if any are currently open (in
start_transaction() and btrfs_throttle()).  The start transaction ioctl
uses a new btrfs_start_ioctl_transaction() that _does_ call
wait_current_trans(), effectively pushing the join/wait decision to the
outer ioctl-initiated transaction.

This more or less neuters btrfs_throttle() when ioctl-initiated
transactions are in use, but that seems like a pretty fundamental
consequence of wrapping lots of write()'s in a transaction.  Btrfs has no
way to tell if the application considers a given operation as part of it's
transaction.

Obviously, if the transaction start/stop ioctls aren't being used, there
is no effect on current behavior.

Signed-off-by: Sage Weil <sage@newdream.net>
---
 ctree.h       |    1 +
 ioctl.c       |   12 +++++++++++-
 transaction.c |   18 +++++++++++++-----
 transaction.h |    2 ++
 4 files changed, 27 insertions(+), 6 deletions(-)

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:06 -04:00
Chris Mason 2dd3e67b1e Btrfs: More throttle tuning
* Make walk_down_tree wake up throttled tasks more often
* Make walk_down_tree call cond_resched during long loops
* As the size of the ref cache grows, wait longer in throttle
* Get rid of the reada code in walk_down_tree, the leaves don't get
  read anymore, thanks to the ref cache.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:06 -04:00
Chris Mason 65b51a009e btrfs_search_slot: reduce lock contention by cowing in two stages
A btree block cow has two parts, the first is to allocate a destination
block and the second is to copy the old bock over.

The first part needs locks in the extent allocation tree, and may need to
do IO.  This changeset splits that into a separate function that can be
called without any tree locks held.

btrfs_search_slot is changed to drop its path and start over if it has
to COW a contended block.  This often means that many writers will
pre-alloc a new destination for a the same contended block, but they
cache their prealloc for later use on lower levels in the tree.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:06 -04:00
Chris Mason 18e35e0ab3 Btrfs: Throttle less often waiting for snapshots to delete
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:06 -04:00
Chris Mason 37d1aeee39 Btrfs: Throttle tuning
This avoids waiting for transactions with pages locked by breaking out
the code to wait for the current transaction to close into a function
called by btrfs_throttle.

It also lowers the limits for where we start throttling.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Yan bcc63abbf3 Btrfs: implement memory reclaim for leaf reference cache
The memory reclaiming issue happens when snapshot exists. In that
case, some cache entries may not be used during old snapshot dropping,
so they will remain in the cache until umount.

The patch adds a field to struct btrfs_leaf_ref to record create time. Besides,
the patch makes all dead roots of a given snapshot linked together in order of
create time. After a old snapshot was completely dropped, we check the dead
root list and remove all cache entries created before the oldest dead root in
the list.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Yan Zheng f321e49103 Btrfs: Update and fix mount -o nodatacow
To check whether a given file extent is referenced by multiple snapshots, the
checker walks down the fs tree through dead root and checks all tree blocks in
the path.

We can easily detect whether a given tree block is directly referenced by other
snapshot. We can also detect any indirect reference from other snapshot by
checking reference's generation. The checker can always detect multiple
references, but can't reliably detect cases of single reference. So btrfs may
do file data cow even there is only one reference.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Chris Mason ab78c84de1 Btrfs: Throttle operations if the reference cache gets too large
A large reference cache is directly related to a lot of work pending
for the cleaner thread.  This throttles back new operations based on
the size of the reference cache so the cleaner thread will be able to keep
up.

Overall, this actually makes the FS faster because the cleaner thread will
be more likely to find things in cache.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Chris Mason 017e5369eb Btrfs: Leaf reference cache update
This changes the reference cache to make a single cache per root
instead of one cache per transaction, and to key by the byte number
of the disk block instead of the keys inside.

This makes it much less likely to have cache misses if a snapshot
or something has an extra reference on a higher node or a leaf while
the first transaction that added the leaf into the cache is dropping.

Some throttling is added to functions that free blocks heavily so they
wait for old transactions to drop.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Yan Zheng 31153d8128 Btrfs: Add a leaf reference cache
Much of the IO done while dropping snapshots is done looking up
leaves in the filesystem trees to see if they point to any extents and
to drop the references on any extents found.

This creates a cache so that IO isn't required.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Josef Bacik aec7477b3b Btrfs: Implement new dir index format
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Chris Mason ed98b56a63 Btrfs: Take the csum mutex while reading checksums
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Chris Mason f421950f86 Btrfs: Fix some data=ordered related data corruptions
Stress testing was showing data checksum errors, most of which were caused
by a lookup bug in the extent_map tree.  The tree was caching the last
pointer returned, and searches would check the last pointer first.

But, search callers also expect the search to return the very first
matching extent in the range, which wasn't always true with the last
pointer usage.

For now, the code to cache the last return value is just removed.  It is
easy to fix, but I think lookups are rare enough that it isn't required anymore.

This commit also replaces do_sync_mapping_range with a local copy of the
related functions.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:05 -04:00
Chris Mason f929574938 btrfs_start_transaction: wait for commits in progress to finish
btrfs_commit_transaction has to loop waiting for any writers in the
transaction to finish before it can proceed.  btrfs_start_transaction
should be polite and not join a transaction that is in the process
of being finished off.

There are a few places that can't wait, basically the ones doing IO that
might be needed to finish the transaction.  For them, btrfs_join_transaction
is added.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:04 -04:00
Chris Mason e6dcd2dc9c Btrfs: New data=ordered implementation
The old data=ordered code would force commit to wait until
all the data extents from the transaction were fully on disk.  This
introduced large latencies into the commit and stalled new writers
in the transaction for a long time.

The new code changes the way data allocations and extents work:

* When delayed allocation is filled, data extents are reserved, and
  the extent bit EXTENT_ORDERED is set on the entire range of the extent.
  A struct btrfs_ordered_extent is allocated an inserted into a per-inode
  rbtree to track the pending extents.

* As each page is written EXTENT_ORDERED is cleared on the bytes corresponding
  to that page.

* When all of the bytes corresponding to a single struct btrfs_ordered_extent
  are written, The previously reserved extent is inserted into the FS
  btree and into the extent allocation trees.  The checksums for the file
  data are also updated.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:04 -04:00
Chris Mason 77a41afb7d Btrfs: Drop some verbose printks
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:04 -04:00
Chris Mason 3f157a2fd2 Btrfs: Online btree defragmentation fixes
The btree defragger wasn't making forward progress because the new key wasn't
being saved by the btrfs_search_forward function.

This also disables the automatic btree defrag, it wasn't scaling well to
huge filesystems.  The auto-defrag needs to be done differently.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:04 -04:00
Chris Mason 1b1e2135dc Btrfs: Add a per-inode csum mutex to avoid races creating csum items
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:04 -04:00
Chris Mason a74a4b97b6 Btrfs: Replace the transaction work queue with kthreads
This creates one kthread for commits and one kthread for
deleting old snapshots.  All the work queues are removed.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:03 -04:00
Chris Mason 89ce8a63d0 Add btrfs_end_transaction_throttle to force writers to wait for pending commits
The existing throttle mechanism was often not sufficient to prevent
new writers from coming in and making a given transaction run forever.
This adds an explicit wait at the end of most operations so they will
allow the current transaction to close.

There is no wait inside file_write, inode updates, or cow filling, all which
have different deadlock possibilities.

This is a temporary measure until better asynchronous commit support is
added.  This code leads to stalls as it waits for data=ordered
writeback, and it really needs to be fixed.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:03 -04:00
Chris Mason a213501153 Btrfs: Replace the big fs_mutex with a collection of other locks
Extent alloctions are still protected by a large alloc_mutex.
Objectid allocations are covered by a objectid mutex
Other btree operations are protected by a lock on individual btree nodes

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:03 -04:00
Chris Mason 925baeddc5 Btrfs: Start btree concurrency work.
The allocation trees and the chunk trees are serialized via their own
dedicated mutexes.  This means allocation location is still not very
fine grained.

The main FS btree is protected by locks on each block in the btree.  Locks
are taken top / down, and as processing finishes on a given level of the
tree, the lock is released after locking the lower level.

The end result of a search is now a path where only the lowest level
is locked.  Releasing or freeing the path drops any locks held.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:03 -04:00
Sven Wegener 3b96362cc8 Btrfs: Invalidate dcache entry after creating snapshot and
We need to invalidate an existing dcache entry after creating a new
snapshot or subvolume, because a negative dache entry will stop us from
accessing the new snapshot or subvolume.

---
  ctree.h       |   23 +++++++++++++++++++++++
  inode.c       |    4 ++++
  transaction.c |    4 ++++
  3 files changed, 31 insertions(+)

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:03 -04:00
Chris Mason 48ec2cf873 Btrfs: Fix race in running_transaction checks
When a new transaction was started, the code would incorrectly
set the pointer in fs_info before all the data structures were setup.
fsync heavy workloads hit races on the setup of the ordered inode spinlock

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:03 -04:00
Chris Mason a061fc8da7 Btrfs: Add support for online device removal
This required a few structural changes to the code that manages bdev pointers:

The VFS super block now gets an anon-bdev instead of a pointer to the
lowest bdev.  This allows us to avoid swapping the super block bdev pointer
around at run time.

The code to read in the super block no longer goes through the extent
buffer interface.  Things got ugly keeping the mapping constant.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:02 -04:00
Chris Mason d6bfde8765 Btrfs: Fixes for 2.6.18 enterprise kernels
2.6.18 seems to get caught in an infinite loop when
cancel_rearming_delayed_workqueue is called more than once, so this switches
to cancel_delayed_work, which is arguably more correct.

Also, balance_dirty_pages can run into problems with 2.6.18 based kernels
because it doesn't have the per-bdi dirty limits.  This avoids calling
balance_dirty_pages on the btree inode unless there is actually something
to balance, which is a good optimization in general.

Finally there's a compile fix for ordered-data.h

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:02 -04:00
Chris Mason 81d7ed29ff Btrfs: Throttle file_write when data=ordered is flushing the inode
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:02 -04:00
Chris Mason ce9adaa5a7 Btrfs: Do metadata checksums for reads via a workqueue
Before, metadata checksumming was done by the callers of read_tree_block,
which would set EXTENT_CSUM bits in the extent tree to show that a given
range of pages was already checksummed and didn't need to be verified
again.

But, those bits could go away via try_to_releasepage, and the end
result was bogus checksum failures on pages that never left the cache.

The new code validates checksums when the page is read.  It is a little
tricky because metadata blocks can span pages and a single read may
end up going via multiple bios.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:01 -04:00
Chris Mason 0b86a832a1 Btrfs: Add support for multiple devices per filesystem
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:00 -04:00
Chris Mason 80b6794d11 Btrfs: Lower stack usage in transaction.c
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:00 -04:00
Chris Mason 4529ba495c Btrfs: Add data block hints to SSD mode too
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:00 -04:00
Chris Mason d1310b2e0c Btrfs: Split the extent_map code into two parts
There is now extent_map for mapping offsets in the file to disk and
extent_io for state tracking, IO submission and extent_bufers.

The new extent_map code shifts from [start,end] pairs to [start,len], and
pushes the locking out into the caller.  This allows a few performance
optimizations and is easier to use.

A number of extent_map usage bugs were fixed, mostly with failing
to remove extent_map entries when changing the file.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:59 -04:00
Chris Mason e18e4809b1 Btrfs: Add mount -o ssd, which includes optimizations for seek free storage
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:59 -04:00
Chris Mason 4d5e74bc0a Btrfs: Fix data=ordered vs wait_on_inode deadlock on older kernels
Using ilookup5 during data=ordered writeback could deadlock on I_LOCK.  This
saves a pointer to the inode instead.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:59 -04:00
Chris Mason 2da98f003f Btrfs: Run igrab on data=ordered inodes to prevent deadlocks during writeout
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:59 -04:00
Chris Mason cee36a03e8 Rework btrfs_drop_inode to avoid scheduling
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:59 -04:00
Chris Mason e2008b6140 Btrfs: Add some simple throttling to wait for data=ordered and snapshot deletion
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:59 -04:00
Chris Mason 3063d29f2a Btrfs: Move snapshot creation to commit time
It is very difficult to create a consistent snapshot of the btree when
other writers may update the btree before the commit is done.

This changes the snapshot creation to happen during the commit, while
no other updates are possible.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:59 -04:00
Chris Mason dc17ff8f11 Btrfs: Add data=ordered support
This forces file data extents down the disk along with the metadata that
references them.  The current implementation is fairly simple, and just
writes out all of the dirty pages in an inode before the commit.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:59 -04:00
Chris Mason 4313b3994d Btrfs: Reduce stack usage in the resizer, fix 32 bit compiles
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:58 -04:00
Chris Mason 6da6abae02 Btrfs: Back port to 2.6.18-el kernels
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:58 -04:00
Christian Hesse 17636e03f4 Btrfs: section mismatch warnings
--Boundary-00=_CcOWHFYK4T+JwSj
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

Hello everybody,

compiling btrfs into the kernel results in section mismatch warnings. __exit
functions are called where they are not allowed to. The attached patch fixes
this for me. Not sure if it is correct though.

Signed-off-by: Christian Hesse <mail@earthworm.de>
--
Regards,
Chris

--Boundary-00=_CcOWHFYK4T+JwSj
Content-Type: text/x-diff; charset="iso-8859-1";
	name="btrfs-section_mismatches.patch"
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment;
	filename="btrfs-section_mismatches.patch"

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:58 -04:00
Chris Mason 35ebb934bd Btrfs: Fix PAGE_CACHE_SHIFT shifts on 32 bit machines
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:57 -04:00
Chris Mason a6b6e75e09 Btrfs: Defrag only leaves, and only when the parent node has a single objectid
This allows us to defrag huge directories, but skip the expensive defrag
case in more common usage, where it does not help as much.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:57 -04:00
Chris Mason 4dc119046d Btrfs: Add an extent buffer LRU to reduce radix tree hits
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:56 -04:00
Chris Mason 6b80053d02 Btrfs: Add back the online defragging code
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:56 -04:00
Chris Mason db94535db7 Btrfs: Allow tree blocks larger than the page size
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:56 -04:00
Chris Mason 1a5bc167f6 Btrfs: Change the remaining radix trees used by extent-tree.c to extent_map trees
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:56 -04:00
Chris Mason f510cfecfc Btrfs: Fix extent_buffer and extent_state leaks
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:56 -04:00
Chris Mason 5f39d397df Btrfs: Create extent_buffer interface for large blocksizes
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:56 -04:00
Chris Mason d3c2fdcf7b Btrfs: Use balance_dirty_pages_nr on btree blocks
btrfs_btree_balance_dirty is changed to pass the number of pages dirtied
for more accurate dirty throttling.  This lets the VM make better decisions
about when to force some writeback.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:00:48 -04:00
Chris Mason 5ce14bbcdd Btrfs: Find and remove dead roots the first time a root is loaded.
Dead roots are trees left over after a crash, and they were either in the
process of being removed or were waiting to be removed when the box crashed.
Before, a search of the entire tree of root pointers was done on mount
looking for dead roots.  Now, the search is done the first time we load
a root.

This makes mount faster when there are a large number of snapshots, and it
enables the block accounting code to properly update the block counts on
the latest root as old versions of the root are reaped after a crash.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-09-11 11:15:39 -04:00
Josef Bacik 58176a9604 Btrfs: Add per-root block accounting and sysfs entries
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-29 15:47:34 -04:00
Josef Bacik 15ee9bc7ed Btrfs: delay commits during fsync to allow more writers
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-10 16:22:09 -04:00
Chris Mason e9d0b13b5b Btrfs: Btree defrag on the extent-mapping tree as well
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-10 14:06:19 -04:00
Chris Mason 409eb95d7f Btrfs: Further reduce the concurrency penalty of defrag and drop_snapshot
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-08 20:17:12 -04:00
Chris Mason 26b8003f10 Btrfs: Replace extent tree preallocation code with some bit radix magic.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-08 20:17:12 -04:00
Chris Mason f4468e94c8 Btrfs: Let some locks go during defrag and snapshot dropping
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-08 10:08:58 -04:00
Chris Mason 6702ed490c Btrfs: Add run time btree defrag, and an ioctl to force btree defrag
This adds two types of btree defrag, a run time form that tries to
defrag recently allocated blocks in the btree when they are still in ram,
and an ioctl that forces defrag of all btree blocks.

File data blocks are not defragged yet, but this can make a huge difference
in sequential btree reads.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-07 16:15:09 -04:00
Chris Mason 9f3a742736 Btrfs: Do snapshot deletion in smaller chunks.
Before, snapshot deletion was a single atomic unit.  This caused considerable
lock contention and required an unbounded amount of space.  Now,
the drop_progress field in the root item is used to indicate how far along
snapshot deletion is, and to resume where it left off.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-07 15:52:19 -04:00
Zach Brown ec6b910fb3 Btrfs: trivial include fixups
Almost none of the files including module.h need to do so,
remove them.

Include sched.h in extent-tree.c to silence a warning about cond_resched()
being undeclared.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-07-11 10:00:37 -04:00
Chris Mason ccd467d60e Btrfs: crash recovery fixes
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-28 15:57:36 -04:00
Chris Mason 4b52dff6d3 Btrfs: Fix super block updates during transaction commit
The super block written during commit was not consistent with the state of
the trees.  This change adds an in-memory copy of the super so that we can
make sure to write out consistent data during a commit.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-26 10:06:50 -04:00
Chris Mason 22bb92f376 Btrfs: Documentation update
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-22 14:49:31 -04:00
Chris Mason 5eda7b5e9b Btrfs: Add the ability to find and remove dead roots after a crash.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-22 14:16:25 -04:00
Chris Mason 54aa1f4dfd Btrfs: Audit callers and return codes to make sure -ENOSPC gets up the stack
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-22 14:16:25 -04:00
Chris Mason 8c2383c3dd Subject: Rework btrfs_file_write to only allocate while page locks are held
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-18 09:57:58 -04:00
Chris Mason 340887809d Btrfs: i386 fixes from axboe
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-12 11:36:58 -04:00
Chris Mason 6cbd557078 Btrfs: add GPLv2
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-12 09:07:21 -04:00
Chris Mason 0cf6c62017 Btrfs: remove device tree
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-09 09:22:25 -04:00
Chris Mason ad693af684 Btrfs: reap dead roots right after commit
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-09 08:19:57 -04:00
Chris Mason facda1e787 Btrfs: get forced transaction commits via workqueue
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-08 18:11:48 -04:00
Chris Mason 08607c1b18 Btrfs: add compat ioctl
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-08 15:33:54 -04:00
Chris Mason e37c9e6921 Btrfs: many allocator fixes, pretty solid
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-05-09 20:13:14 -04:00
Chris Mason 35b7e47610 Btrfs: fix page cache memory leak
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-05-02 15:53:43 -04:00
Chris Mason 31f3c99b73 Btrfs: allocator improvements, inode block groups
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-30 15:25:45 -04:00
Chris Mason 7c4452b9a6 Btrfs: smarter transaction writeback
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-28 09:29:35 -04:00
Chris Mason 9078a3e1e4 Btrfs: start of block group code
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-26 16:46:15 -04:00
Chris Mason 8fd17795b2 Btrfs: early fsync support
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-19 21:01:03 -04:00
Chris Mason 8352d8a473 Btrfs: add disk ioctl, mostly working
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-12 10:43:05 -04:00
Chris Mason 7eccb903a8 Btrfs: create a logical->phsyical block number mapping scheme
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-11 15:53:25 -04:00
Chris Mason 2619ba1f0f Btrfs: subvolumes
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-10 16:58:11 -04:00
Chris Mason d0dbc6245c Btrfs: drop owner and parentid
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-10 12:36:36 -04:00
Chris Mason 1b05da2ee6 Btrfs: drop the inode map tree
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-10 12:13:09 -04:00
Chris Mason 0f7d52f443 Btrfs: groundwork for subvolume and snapshot roots
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-09 10:42:37 -04:00
Chris Mason d6e4a428eb Btrfs: start of support for many FS volumes
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-06 15:37:36 -04:00
Chris Mason 7cfcc17e7f Btrfs: corruptions fixed
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-02 14:53:59 -04:00
Chris Mason 2c90e5d658 Btrfs: still corruption hunting
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-02 10:50:19 -04:00
Chris Mason d602557953 Btrfs: corruption hunt continues
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-03-30 14:27:56 -04:00
Chris Mason 22b0ebda6c Btrfs: hunting slab corruption
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-03-30 08:47:31 -04:00
Chris Mason d98237b3ed Btrfs: use a btree inode instead of sb_getblk
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-03-28 13:57:48 -04:00
Chris Mason 78fae27ebf Btrfs: leak fixes, pinning fixes
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-03-25 11:35:08 -04:00
Chris Mason d571976292 btrfs_create, btrfs_write_super, btrfs_sync_fs
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-03-23 10:01:08 -04:00
Chris Mason 79154b1b5b Btrfs: transaction rework
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-03-22 15:59:16 -04:00