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2012-01-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit: (29 commits) audit: no leading space in audit_log_d_path prefix audit: treat s_id as an untrusted string audit: fix signedness bug in audit_log_execve_info() audit: comparison on interprocess fields audit: implement all object interfield comparisons audit: allow interfield comparison between gid and ogid audit: complex interfield comparison helper audit: allow interfield comparison in audit rules Kernel: Audit Support For The ARM Platform audit: do not call audit_getname on error audit: only allow tasks to set their loginuid if it is -1 audit: remove task argument to audit_set_loginuid audit: allow audit matching on inode gid audit: allow matching on obj_uid audit: remove audit_finish_fork as it can't be called audit: reject entry,always rules audit: inline audit_free to simplify the look of generic code audit: drop audit_set_macxattr as it doesn't do anything audit: inline checks for not needing to collect aux records audit: drop some potentially inadvisable likely notations ... Use evil merge to fix up grammar mistakes in Kconfig file. Bad speling and horrible grammar (and copious swearing) is to be expected, but let's keep it to commit messages and comments, rather than expose it to users in config help texts or printouts.
2012-01-17Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfsLinus Torvalds
* 'for-linus' of git://oss.sgi.com/xfs/xfs: xfs: cleanup xfs_file_aio_write xfs: always return with the iolock held from xfs_file_aio_write_checks xfs: remove the i_new_size field in struct xfs_inode xfs: remove the i_size field in struct xfs_inode xfs: replace i_pin_wait with a bit waitqueue xfs: replace i_flock with a sleeping bitlock xfs: make i_flags an unsigned long xfs: remove the if_ext_max field in struct xfs_ifork xfs: remove the unused dm_attrs structure xfs: cleanup xfs_iomap_eof_align_last_fsb xfs: remove xfs_itruncate_data
2012-01-17Merge branch 'btrfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds
* '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
2012-01-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (62 commits) Btrfs: use larger system chunks Btrfs: add a delalloc mutex to inodes for delalloc reservations Btrfs: space leak tracepoints Btrfs: protect orphan block rsv with spin_lock Btrfs: add allocator tracepoints Btrfs: don't call btrfs_throttle in file write Btrfs: release space on error in page_mkwrite Btrfs: fix btrfsck error 400 when truncating a compressed Btrfs: do not use btrfs_end_transaction_throttle everywhere Btrfs: add balance progress reporting Btrfs: allow for resuming restriper after it was paused Btrfs: allow for canceling restriper Btrfs: allow for pausing restriper Btrfs: add skip_balance mount option Btrfs: recover balance on mount Btrfs: save balance parameters to disk Btrfs: soft profile changing mode (aka soft convert) Btrfs: implement online profile changing Btrfs: do not reduce profile in do_chunk_alloc() Btrfs: virtual address space subset filter ... Fix up trivial conflict in fs/btrfs/ioctl.c due to the use of the new mnt_drop_write_file() helper.
2012-01-17proc: clean up and fix /proc/<pid>/mem handlingLinus Torvalds
Jüri Aedla reported that the /proc/<pid>/mem handling really isn't very robust, and it also doesn't match the permission checking of any of the other related files. This changes it to do the permission checks at open time, and instead of tracking the process, it tracks the VM at the time of the open. That simplifies the code a lot, but does mean that if you hold the file descriptor open over an execve(), you'll continue to read from the _old_ VM. That is different from our previous behavior, but much simpler. If somebody actually finds a load where this matters, we'll need to revert this commit. I suspect that nobody will ever notice - because the process mapping addresses will also have changed as part of the execve. So you cannot actually usefully access the fd across a VM change simply because all the offsets for IO would have changed too. Reported-by: Jüri Aedla <asd@ut.ee> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-17audit: do not call audit_getname on errorEric Paris
Just a code cleanup really. We don't need to make a function call just for it to return on error. This also makes the VFS function even easier to follow and removes a conditional on a hot path. Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17audit: only allow tasks to set their loginuid if it is -1Eric Paris
At the moment we allow tasks to set their loginuid if they have CAP_AUDIT_CONTROL. In reality we want tasks to set the loginuid when they log in and it be impossible to ever reset. We had to make it mutable even after it was once set (with the CAP) because on update and admin might have to restart sshd. Now sshd would get his loginuid and the next user which logged in using ssh would not be able to set his loginuid. Systemd has changed how userspace works and allowed us to make the kernel work the way it should. With systemd users (even admins) are not supposed to restart services directly. The system will restart the service for them. Thus since systemd is going to loginuid==-1, sshd would get -1, and sshd would be allowed to set a new loginuid without special permissions. If an admin in this system were to manually start an sshd he is inserting himself into the system chain of trust and thus, logically, it's his loginuid that should be used! Since we have old systems I make this a Kconfig option. Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17audit: remove task argument to audit_set_loginuidEric Paris
The function always deals with current. Don't expose an option pretending one can use it for something. You can't. Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17xfs: cleanup xfs_file_aio_writeChristoph Hellwig
With all the size field updates out of the way xfs_file_aio_write can be further simplified by pushing all iolock handling into xfs_file_dio_aio_write and xfs_file_buffered_aio_write and using the generic generic_write_sync helper for synchronous writes. Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: always return with the iolock held from xfs_file_aio_write_checksChristoph Hellwig
While xfs_iunlock is fine with 0 lockflags the calling conventions are much cleaner if xfs_file_aio_write_checks never returns without the iolock held. Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: remove the i_new_size field in struct xfs_inodeChristoph Hellwig
Now that we use the VFS i_size field throughout XFS there is no need for the i_new_size field any more given that the VFS i_size field gets updated in ->write_end before unlocking the page, and thus is always uptodate when writeback could see a page. Removing i_new_size also has the advantage that we will never have to trim back di_size during a failed buffered write, given that it never gets updated past i_size. Note that currently the generic direct I/O code only updates i_size after calling our end_io handler, which requires a small workaround to make sure di_size actually makes it to disk. I hope to fix this properly in the generic code. A downside is that we lose the support for parallel non-overlapping O_DIRECT appending writes that recently was added. I don't think keeping the complex and fragile i_new_size infrastructure for this is a good tradeoff - if we really care about parallel appending writers we should investigate turning the iolock into a range lock, which would also allow for parallel non-overlapping buffered writers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: remove the i_size field in struct xfs_inodeChristoph Hellwig
There is no fundamental need to keep an in-memory inode size copy in the XFS inode. We already have the on-disk value in the dinode, and the separate in-memory copy that we need for regular files only in the XFS inode. Remove the xfs_inode i_size field and change the XFS_ISIZE macro to use the VFS inode i_size field for regular files. Switch code that was directly accessing the i_size field in the xfs_inode to XFS_ISIZE, or in cases where we are limited to regular files direct access of the VFS inode i_size field. This also allows dropping some fairly complicated code in the write path which dealt with keeping the xfs_inode i_size uptodate with the VFS i_size that is getting updated inside ->write_end. Note that we do not bother resetting the VFS i_size when truncating a file that gets freed to zero as there is no point in doing so because the VFS inode is no longer in use at this point. Just relax the assert in xfs_ifree to only check the on-disk size instead. Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: replace i_pin_wait with a bit waitqueueChristoph Hellwig
Replace i_pin_wait, which is only used during synchronous inode flushing with a bit waitqueue. This trades off a much smaller inode against slightly slower wakeup performance, and saves 12 (32-bit) or 20 (64-bit) bytes in the XFS inode. Reviewed-by: Alex Elder <aelder@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: replace i_flock with a sleeping bitlockChristoph Hellwig
We almost never block on i_flock, the exception is synchronous inode flushing. Instead of bloating the inode with a 16/24-byte completion that we abuse as a semaphore just implement it as a bitlock that uses a bit waitqueue for the rare sleeping path. This primarily is a tradeoff between a much smaller inode and a faster non-blocking path vs faster wakeups, and we are much better off with the former. A small downside is that we will lose lockdep checking for i_flock, but given that it's always taken inside the ilock that should be acceptable. Note that for example the inode writeback locking is implemented in a very similar way. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: make i_flags an unsigned longChristoph Hellwig
To be used for bit wakeup i_flags needs to be an unsigned long or we'll run into trouble on big endian systems. Because of the 1-byte i_update field right after it this actually causes a fairly large size increase on its own (4 or 8 bytes), but that increase will be more than offset by the next two patches. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: remove the if_ext_max field in struct xfs_iforkChristoph Hellwig
We spent a lot of effort to maintain this field, but it always equals to the fork size divided by the constant size of an extent. The prime use of it is to assert that the two stay in sync. Just divide the fork size by the extent size in the few places that we actually use it and remove the overhead of maintaining it. Also introduce a few helpers to consolidate the places where we actually care about the value. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-16Merge tag 'nfs-for-3.3-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
NFS client bugfixes and cleanups for Linux 3.3 (pull 2) * tag 'nfs-for-3.3-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: pnfsblock: alloc short extent before submit bio pnfsblock: remove rpc_call_ops from struct parallel_io pnfsblock: move find lock page logic out of bl_write_pagelist pnfsblock: cleanup bl_mark_sectors_init pnfsblock: limit bio page count pnfsblock: don't spinlock when freeing block_dev pnfsblock: clean up _add_entry pnfsblock: set read/write tk_status to pnfs_error pnfsblock: acquire im_lock in _preload_range NFS4: fix compile warnings in nfs4proc.c nfs: check for integer overflow in decode_devicenotify_args() NFS: cleanup endian type in decode_ds_addr() NFS: add an endian notation
2012-01-16Btrfs: use larger system chunksChris Mason
system chunks by default are very small. This makes them slightly larger and also fixes the conditional checks to make sure we don't allocate a billion of them at once. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-16Btrfs: add a delalloc mutex to inodes for delalloc reservationsJosef Bacik
I was using i_mutex for this, but we're getting bogus lockdep warnings by doing that and theres no real way to get rid of those, so just stop using i_mutex to protect delalloc metadata reservations and use a delalloc mutex instead. This shouldn't be contended often at all, only if you are writing and mmap writing to the file at the same time. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2012-01-16Btrfs: space leak tracepointsJosef Bacik
This in addition to a script in my btrfs-tracing tree will help track down space leaks when we're getting space left over in block groups on umount. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2012-01-16Btrfs: protect orphan block rsv with spin_lockJosef Bacik
We've been seeing warnings coming out of the orphan commit stuff forever from ceph. Turns out it's because we're racing with checking if the orphan block reserve is set, because we clear it outside of the spin_lock. So leave the normal fastpath checks where they are, but take the spin_lock and _recheck_ to make sure we haven't had an orphan block rsv added in the meantime. Then clear the root's orphan block rsv and release the lock. With this patch a user said the warnings went away and they usually showed up pretty soon after he started ceph. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2012-01-16Btrfs: add allocator tracepointsJosef Bacik
I used these tracepoints when figuring out what the cluster stuff was doing, so add them to mainline in case we need to profile this stuff again. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2012-01-16Btrfs: don't call btrfs_throttle in file writeJosef Bacik
Btrfs_throttle will make us wait if there is a currently committing transaction until we can open new transactions, which is ridiculous since we don't actually start any transactions within the file write path anyway, so all this does is introduce big latencies if we have a sync/fsync heavy workload going on while somebody else is trying to do work. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-16Btrfs: release space on error in page_mkwriteJosef Bacik
If updating the inode gave us an ENOSPC we were just returning in page_mkwrite, which is a problem since we make our reservation right before trying to update the inode, so fix the out label so that we actually free our reservation. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-16Btrfs: fix btrfsck error 400 when truncating a compressedMiao Xie
Reproduce steps: # mkfs.btrfs /dev/sdb5 # mount /dev/sdb5 -o compress=lzo /mnt # dd if=/dev/zero of=/mnt/tmpfile bs=128K count=1 # sync # truncate -s 64K /mnt/tmpfile root 5 inode 257 errors 400 This is because of the wrong if condition, which is used to check if we should subtract the bytes of the dropped range from i_blocks/i_bytes of i-node or not. When we truncate a compressed extent, btrfs substracts the bytes of the whole extent, it's wrong. We should substract the real size that we truncate, no matter it is a compressed extent or not. Fix it. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-16Btrfs: do not use btrfs_end_transaction_throttle everywhereJosef Bacik
A user reported a problem where things like open with O_CREAT would take up to 30 seconds when he had nfs activity on the same mount. This is because all of our quick metadata operations, like create, symlink etc all do btrfs_end_transaction_throttle, which if the transaction is blocked will wait for the commit to complete before it returns. This adds a ridiculous amount of latency and isn't really needed. The normal btrfs_end_transaction will mark the transaction as blocked and wake the transaction kthread up if it thinks the transaction needs to end (this being in the running out of global reserve space scenario), and this is all that is really needed since we've already done everything we're going to do, we just need to return. This should help people with the latency they were seeing when using synchronous heavy workloads. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-16Merge branch 'integrity-check-patch-v2' of ↵Chris Mason
git://btrfs.giantdisaster.de/git/btrfs into integration Conflicts: fs/btrfs/ctree.h fs/btrfs/super.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-16Merge branch 'for-chris' of git://git.jan-o-sch.net/btrfs-unstable into ↵Chris Mason
integration
2012-01-16Merge branch 'for-chris' of git://repo.or.cz/linux-btrfs-devel into integrationChris Mason
Conflicts: fs/btrfs/volumes.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-16Merge branch 'restriper' of git://github.com/idryomov/btrfs-unstable into ↵Chris Mason
integration
2012-01-16Merge branch 'allocation-fixes' into integrationChris Mason
2012-01-16Btrfs: add balance progress reportingIlya Dryomov
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: allow for resuming restriper after it was pausedIlya Dryomov
Recognize BTRFS_BALANCE_RESUME flag passed from userspace. We use the same heuristics used when recovering balance after a crash to try to start where we left off last time. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: allow for canceling restriperIlya Dryomov
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>
2012-01-16Btrfs: allow for pausing restriperIlya Dryomov
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>
2012-01-16Btrfs: add skip_balance mount optionIlya Dryomov
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>
2012-01-16Btrfs: recover balance on mountIlya Dryomov
On mount, if balance item is found, resume balance in a separate kernel thread. Try to be smart to continue roughly where previous balance (or convert) was interrupted. For chunk types that were being converted to some profile we turn on soft convert, in case of a simple balance we turn on usage filter and relocate only less-than-90%-full chunks of that type. These are just heuristics but they help quite a bit, and can be improved in future. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: save balance parameters to diskIlya Dryomov
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>
2012-01-16Btrfs: soft profile changing mode (aka soft convert)Ilya Dryomov
When doing convert from one profile to another if soft mode is on restriper won't touch chunks that already have the profile we are converting to. This is useful if e.g. half of the FS was converted earlier. The soft mode switch is (like every other filter) per-type. This means that we can convert for example meta chunks the "hard" way while converting data chunks selectively with soft switch. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: implement online profile changingIlya Dryomov
Profile changing is done by launching a balance with BTRFS_BALANCE_CONVERT bits set and target fields of respective btrfs_balance_args structs initialized. Profile reducing code in this case will pick restriper's target profile if it's available instead of doing a blind reduce. If target profile is not yet available it goes back to a plain reduce. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: do not reduce profile in do_chunk_alloc()Ilya Dryomov
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>
2012-01-16Btrfs: virtual address space subset filterIlya Dryomov
Select chunks which have at least one byte located inside a given [vstart, vend) virtual address space range. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: devid subset filterIlya Dryomov
Select chunks which have at least one byte of at least one stripe located on a device with devid X in a given [pstart,pend) physical address range. This filter only works when devid filter is turned on. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: devid filterIlya Dryomov
Relocate chunks which have at least one stripe located on a device with devid X. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: usage filterIlya Dryomov
Select chunks that are less than X percent full. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: profiles filterIlya Dryomov
Select chunks based on a given profile mask. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: add basic infrastructure for selective balancingIlya Dryomov
This allows to have a separate set of filters for each chunk type (data,meta,sys). The code however is generic and switch on chunk type is only done once. This commit also adds a type filter: it allows to balance for example meta and system chunks w/o touching data ones. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: add basic restriper infrastructureIlya Dryomov
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>
2012-01-16Btrfs: make avail_*_alloc_bits fields dynamicIlya Dryomov
Currently when new chunks are created respective avail_alloc_bits field is updated to reflect profiles of all chunks present in the system. However when chunks are removed profile bits are never cleared. This patch clears profile bit of respective avail_alloc_bits field when the last chunk with that profile is removed. Restriper needs this to properly operate when "downgrading". Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16Btrfs: add BTRFS_AVAIL_ALLOC_BIT_SINGLE bitIlya Dryomov
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>