Often no exact match is wanted but just the next lower or
higher item. There's a lot of duplicated code throughout
btrfs to deal with the corner cases. This patch adds a
helper function that can facilitate searching.
Signed-off-by: Arne Jansen <sensille@gmx.net>
We've got two mechanisms both required for reliable backref resolving (tree
mod log and holding back delayed refs). You cannot make use of one without
the other. So instead of requiring the user of this mechanism to setup both
correctly, we join them into a single interface.
Additionally, we stop inserting non-blockers into fs_info->tree_mod_seq_list
as we did before, which was of no value.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
We introduce btrfs_next_old_item that uses btrfs_next_old_leaf instead
of btrfs_next_leaf.
btrfs_next_item is also changed to simply call btrfs_next_old_item with
time_seq being 0.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
To make sense of the tree mod log, the backref walker not only needs
btrfs_search_old_slot, but it also called btrfs_next_leaf, which in turn was
calling btrfs_search_slot. This obviously didn't give the correct result.
This commit adds btrfs_next_old_leaf, a drop-in replacement for
btrfs_next_leaf with a time_seq parameter. If it is zero, it behaves exactly
like btrfs_next_leaf. If it is non-zero, it will use btrfs_search_old_slot
with this time_seq parameter.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
The sequence number for delayed refs is needed to postpone certain delayed
refs for a very short period while walking backrefs. Before the tree
modification log, we thought we'd only have to hold back those references
that don't have a counter operation.
While now we've the tree mod log, we're rewinding fs tree blocks to a
defined consistent state. We cannot know in advance for which tree block
we'll be doing rewind operations later. Therefore, we must postpone all the
delayed refs for fs-tree blocks, even those having a counter operation.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Reduce ioprio class of scrub readahead threads to idle priority.
This setting is fixed. This priority has shown the best performance
during all measurements.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
The device statistics are written into the device tree with each
transaction commit. Only modified statistics are written.
When a filesystem is mounted, the device statistics for each involved
device are read from the device tree and used to initialize the
counters.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Ceph was hitting this race where we would remove an inode from the per-root
orphan list before we would release the space we had reserved for the inode.
We actually don't need a list or anything, we just need to make sure the
root doesn't try to free up the orphan reserve until after the inodes have
released their reservations. So use an atomic counter instead of a list on
the root and only decrement the counter after we've released our
reservation. I've tested this as well as several others and we no longer
see the warnings that you would see while running ceph. Thanks,
Btrfs: fix how we deal with the orphan block rsv
Ceph was hitting this race where we would remove an inode from the per-root
orphan list before we would release the space we had reserved for the inode.
We actually don't need a list or anything, we just need to make sure the
root doesn't try to free up the orphan reserve until after the inodes have
released their reservations. So use an atomic counter instead of a list on
the root and only decrement the counter after we've released our
reservation. I've tested this as well as several others and we no longer
see the warnings that you would see while running ceph. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
The tree modification log together with the current state of the tree gives
a consistent, old version of the tree. btrfs_search_old_slot is used to
search through this old version and return old (dummy!) extent buffers.
Naturally, this function cannot do any tree modifications.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
The tree mod log will log modifications made fs-tree nodes. Most
modifications are done by autobalance of the tree. Such changes are recorded
as long as a block entry exists. When released, the log is cleaned.
With the tree modification log, it's possible to reconstruct a consistent
old state of the tree. This is required to do backref walking on a busy
file system.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Three callers of btrfs_free_tree_block or btrfs_alloc_tree_block passed
parameter for_cow = 1. In fact, these two functions should never mark
their tree modification operations as for_cow, because they can change
the number of blocks referenced by a tree.
Hence, we remove the extra for_cow parameter from these functions and
make them pass a zero down.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Pull btrfs fixes from Chris Mason:
"This has our collection of bug fixes. I missed the last rc because I
thought our patches were making NFS crash during my xfs test runs.
Turns out it was an NFS client bug fixed by someone else while I tried
to bisect it.
All of these fixes are small, but some are fairly high impact. The
biggest are fixes for our mount -o remount handling, a deadlock due to
GFP_KERNEL allocations in readdir, and a RAID10 error handling bug.
This was tested against both 3.3 and Linus' master as of this morning."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (26 commits)
Btrfs: reduce lock contention during extent insertion
Btrfs: avoid deadlocks from GFP_KERNEL allocations during btrfs_real_readdir
Btrfs: Fix space checking during fs resize
Btrfs: fix block_rsv and space_info lock ordering
Btrfs: Prevent root_list corruption
Btrfs: fix repair code for RAID10
Btrfs: do not start delalloc inodes during sync
Btrfs: fix that check_int_data mount option was ignored
Btrfs: don't count CRC or header errors twice while scrubbing
Btrfs: fix btrfs_ioctl_dev_info() crash on missing device
btrfs: don't return EINTR
Btrfs: double unlock bug in error handling
Btrfs: always store the mirror we read the eb from
fs/btrfs/volumes.c: add missing free_fs_devices
btrfs: fix early abort in 'remount'
Btrfs: fix max chunk size check in chunk allocator
Btrfs: add missing read locks in backref.c
Btrfs: don't call free_extent_buffer twice in iterate_irefs
Btrfs: Make free_ipath() deal gracefully with NULL pointers
Btrfs: avoid possible use-after-free in clear_extent_bit()
...
The bitfield member mount_opt was too small by one bit to hold the mount
option that enabled to include data extents in the integrity checker.
Since the same issue happened when the BTRFS_MOUNT_PANIC_ON_FATAL_ERROR
option was added (git rebase silently merges so that the increase of the
size of the bitfield member is lost), the bit limit was removed entirely.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
->root_flags is __le64 and all accesses to it go through the helpers
that do proper conversions. Except for btrfs_root_readonly(), which
checks bit 0 as in host-endian...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Readahead already has a define for the max number of mirrors. Scrub
needs such a define now, the rest of the code will need something
like this soon. Therefore the define was added to ctree.h and removed
from the readahead code.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Header file is not a good place to define functions. This also moves a
call to alloc_profile_is_valid() down the stack and removes a redundant
check from __btrfs_alloc_chunk() - alloc_profile_is_valid() takes it
into account.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
"0" is a valid value for an on-disk chunk profile, but it is not a valid
extended profile. (We have a separate bit for single chunks in extended
case)
Also rename it to alloc_profile_is_valid() for clarity.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Add functions to abstract the conversion between chunk and extended
allocation profile formats and switch everybody to use them.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
A few years ago the btrfs code to support blocks lager than
the page size was disabled to fix a few corner cases in the
page cache handling. This fixes the code to properly support
large metadata blocks again.
Since current kernels will crash early and often with larger
metadata blocks, this adds an incompat bit so that older kernels
can't mount it.
This also does away with different blocksizes for nodes and leaves.
You get a single block size for all tree blocks.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We have been passing nothing but (u64)-1 to find_free_extent for search_end in
all of the callers, so it's completely useless, and we've always been passing 0
in as search_start, so just remove them as function arguments and move
search_start into find_free_extent. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
btrfs currently handles most errors with BUG_ON. This patch is a work-in-
progress but aims to handle most errors other than internal logic
errors and ENOMEM more gracefully.
This iteration prevents most crashes but can run into lockups with
the page lock on occasion when the timing "works out."
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Commit cb1b69f4 (Btrfs: forced readonly when btrfs_drop_snapshot() fails)
made btrfs_drop_snapshot return void because there were no callers checking
the return value. That is the wrong order to handle error propogation since
the caller will have no idea that an error has occured and continue on
as if nothing went wrong.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
btrfs_update_root BUG's when it can't alloc a path, yet it can recover
from a search error. This patch returns -ENOMEM instead.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
As part of the effort to eliminate BUG_ON as an error handling
technique, we need to determine which errors are actual logic errors,
which are on-disk corruption, and which are normal runtime errors
e.g. -ENOMEM.
Annotating these error cases is helpful to understand and report them.
This patch adds a btrfs_panic() routine that will either panic
or BUG depending on the new -ofatal_errors={panic,bug} mount option.
Since there are still so many BUG_ONs, it defaults to BUG for now but I
expect that to change once the error handling effort has made
significant progress.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Quoth Chris:
"This is later than I wanted because I got backed up running through
btrfs bugs from the Oracle QA teams. But they are all bug fixes that
we've queued and tested since rc1.
Nothing in particular stands out, this just reflects bug fixing and QA
done in parallel by all the btrfs developers. The most user visible
of these is:
Btrfs: clear the extent uptodate bits during parent transid failures
Because that helps deal with out of date drives (say an iscsi disk
that has gone away and come back). The old code wasn't always
properly retrying the other mirror for this type of failure."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (24 commits)
Btrfs: fix compiler warnings on 32 bit systems
Btrfs: increase the global block reserve estimates
Btrfs: clear the extent uptodate bits during parent transid failures
Btrfs: add extra sanity checks on the path names in btrfs_mksubvol
Btrfs: make sure we update latest_bdev
Btrfs: improve error handling for btrfs_insert_dir_item callers
Btrfs: be less strict on finding next node in clear_extent_bit
Btrfs: fix a bug on overcommit stuff
Btrfs: kick out redundant stuff in convert_extent_bit
Btrfs: skip states when they does not contain bits to clear
Btrfs: check return value of lookup_extent_mapping() correctly
Btrfs: fix deadlock on page lock when doing auto-defragment
Btrfs: fix return value check of extent_io_ops
btrfs: honor umask when creating subvol root
btrfs: silence warning in raid array setup
btrfs: fix structs where bitfields and spinlock/atomic share 8B word
btrfs: delalloc for page dirtied out-of-band in fixup worker
Btrfs: fix memory leak in load_free_space_cache()
btrfs: don't check DUP chunks twice
Btrfs: fix trim 0 bytes after a device delete
...
On ia64, powerpc64 and sparc64 the bitfield is modified through a RMW cycle and current
gcc rewrites the adjacent 4B word, which in case of a spinlock or atomic has
disaterous effect.
https://lkml.org/lkml/2012/2/1/220
Signed-off-by: David Sterba <dsterba@suse.cz>
* 'btrfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
btrfs: take allocation of ->tree_root into open_ctree()
btrfs: let ->s_fs_info point to fs_info, not root...
btrfs: consolidate failure exits in btrfs_mount() a bit
btrfs: make free_fs_info() call ->kill_sb() unconditional
btrfs: merge free_fs_info() calls on fill_super failures
btrfs: kill pointless reassignment of ->s_fs_info in btrfs_fill_super()
btrfs: make open_ctree() return int
btrfs: sanitizing ->fs_info, part 5
btrfs: sanitizing ->fs_info, part 4
btrfs: sanitizing ->fs_info, part 3
btrfs: sanitizing ->fs_info, part 2
btrfs: sanitizing ->fs_info, part 1
btrfs: fix a deadlock in btrfs_scan_one_device()
btrfs: fix mount/umount race
btrfs: get ->kill_sb() of its own
btrfs: preparation to fixing mount/umount race
Implement an ioctl for canceling restriper. Currently we wait until
relocation of the current block group is finished, in future this can be
done by triggering a commit. Balance item is deleted and no memory
about the interrupted balance is kept.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Implement an ioctl for pausing restriper. This pauses the relocation,
but balance is still considered to be "in progress": balance item is
not deleted, other volume operations cannot be started, etc. If paused
in the middle of profile changing operation we will continue making
allocations with the target profile.
Add a hook to close_ctree() to pause restriper and free its data
structures on unmount. (It's safe to unmount when restriper is in
"paused" state, we will resume with the same parameters on the next
mount)
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Since restriper kthread starts involuntarily on mount and can suck cpu
and memory bandwidth add a mount option to forcefully skip it. The
restriper in that case hangs around in paused state and can be resumed
from userspace when it's convenient.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Introduce a new btree objectid for storing balance item. The reason is
to be able to resume restriper after a crash with the same parameters.
Balance item has a very high objectid and goes into tree of tree roots.
The key for the new item is as follows:
[ BTRFS_BALANCE_OBJECTID ; BTRFS_BALANCE_ITEM_KEY ; 0 ]
Older kernels simply ignore it so it's safe to mount with an older
kernel and then go back to the newer one.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Every caller of do_chunk_alloc() feeds it the reduced allocation
profile, so stop trying to reduce it one more time. Instead check the
validity of the passed profile.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Add basic restriper infrastructure: extended balancing ioctl and all
related ioctl data structures, add data structure for tracking
restriper's state to fs_info, etc. The semantics of the old balancing
ioctl are fully preserved.
Explicitly disallow any volume operations when balance is in progress.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Right now on-disk BTRFS_BLOCK_GROUP_* profile bits are used for
avail_{data,metadata,system}_alloc_bits fields, which gather info about
available allocation profiles in the FS. When chunk is created or read
from disk, its profile is OR'ed with the corresponding avail_alloc_bits
field. Since SINGLE is denoted by 0 in the on-disk format, currently
there is no way to tell when such chunks become avaialble. Restriper
needs that information, so add a separate bit for SINGLE profile.
This bit is going to be in-memory only, it should never be written out
to disk, so it's not a disk format change. However to avoid remappings
in future, reserve corresponding on-disk bit.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Chunk's type and profile are encoded in u64 flags field. Introduce
masks to easily access them. Also fix the type of BTRFS_BLOCK_GROUP_*
constants, it should be ULL.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
the latter can be obtained from the former (by looking as ->tree_root)
just as cheaply as we currently are doing the other way round.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add a for_cow parameter to add_delayed_*_ref and pass the appropriate value
from every call site. The for_cow parameter will later on be used to
determine if a ref will change anything with respect to qgroups.
Delayed refs coming from relocation are always counted as for_cow, as they
don't change subvol quota.
Also pass in the fs_info for later use.
btrfs_find_all_roots() will use this as an optimization, as changes that are
for_cow will not change anything with respect to which root points to a
certain leaf. Thus, we don't need to add the current sequence number to
those delayed refs.
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
btrfs_next_item() makes the btrfs path point to the next item, crossing leaf
boundaries if needed.
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>