This adds chunk_objectid and flags, with flags we can recognize whether
the block group is about data or metadata.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We commit transaction in order to reclaim space from pinned bytes because
it could process delayed refs, and in may_commit_transaction(), we check
first if pinned bytes are enough for the required space, we then check if
that plus bytes reserved for delayed insert are enough for the required
space.
This changes the code to the above logic.
Fixes: b150a4f10d ("Btrfs: use a percpu to keep track of possibly pinned bytes")
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reported-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We don't need to take the mutex and zero out wr_cur_bio, as this is
called after the scrub finished.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The helper scrub_free_wr_ctx is used only once and fits into
scrub_free_ctx as it continues sctx shutdown, no need to keep it
separate.
Signed-off-by: David Sterba <dsterba@suse.com>
The helper scrub_setup_wr_ctx is used only once and fits into
scrub_setup_ctx as it continues intialization, no need to keep it
separate.
Signed-off-by: David Sterba <dsterba@suse.com>
can_overcommit using the root to determine the allocation profile
is the only use of a root in the call graph below reserve_metadata_bytes.
It turns out that we only need to know whether the allocation is for
the chunk root or not -- and we can pass that around as a bool instead.
This allows us to pull root usage out of the reservation path all the
way up to reserve_metadata_bytes itself, which uses it only to compare
against fs_info->chunk_root to set the bool. In turn, this eliminates
a bunch of races where we use a particular root too early in the mount
process.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are two places where we don't already know what kind of alloc
profile we need before calling btrfs_get_alloc_profile, but we need
access to a root everywhere we call it.
This patch adds helpers for btrfs_{data,metadata,system}_alloc_profile()
and relegates btrfs_system_alloc_profile to a static for use in those
two cases. The next patch will eliminate one of those.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The end io work queue items have been tracked by the work queues since
"Btrfs: Add async worker threads for pre and post IO checksumming"
(8b71284292) (2008).
Signed-off-by: David Sterba <dsterba@suse.com>
The list used to track checksums in the early version (2.6.29), but I
was able not pinpoint the commit that stopped using it. Everything
apparently works without it for a long time.
Signed-off-by: David Sterba <dsterba@suse.com>
Seems to be unused since the initial commit, we ignore readahead errors
anyway, the full read will handle that if necessary.
Signed-off-by: David Sterba <dsterba@suse.com>
Both btrfs_create_free_space_tree and btrfs_clear_free_space_tree
contain:
if (ret)
return ret;
return 0;
The if statement is only false when ret equals zero, and since we return
zero in such cases, we can safely remove the branching.
Signed-off-by: Sahil Kang <sahil.kang@asilaycomputing.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We only pass GFP_NOFS to btrfs_bio_clone_partial, so lets hardcode it.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
A rewrite of btrfs_submit_direct_hook appears to have introduced a warning:
fs/btrfs/inode.c: In function 'btrfs_submit_direct_hook':
fs/btrfs/inode.c:8467:14: error: 'bio' may be used uninitialized in this function [-Werror=maybe-uninitialized]
Where the 'bio' variable was previously initialized unconditionally, it
is now set in the "while (submit_len > 0)" loop that would never execute
if submit_len is zero.
Assuming this cannot happen in practice, we can avoid the warning
by simply replacing the while{} loop with a do{}while() loop so
the compiler knows that it will always be entered at least once.
Fixes changes introduced in "Btrfs: use bio_clone_bioset_partial to
simplify DIO submit".
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Sterba <dsterba@suse.com>
All dio endio functions are using io_bio for struct btrfs_io_bio, this
makes btrfs_submit_direct to follow this convention.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Some check-integrity code depends on bio->bi_vcnt, this changes it to use
bio segments because some bios passing here may not have a reliable
bi_vcnt.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the nocsum case of dio read endio, it returns immediately if an error
gets returned when repairing, which leaves the rest blocks unrepaired. The
behavior is different from how buffered read endio works in the same case.
This changes it to record error only and go on repairing the rest blocks.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since dio submit has used bio_clone_fast, the submitted bio may not have a
reliable bi_vcnt, for the bio vector iterations in checksum related
functions, bio->bi_iter is not modified yet and it's safe to use
bio_for_each_segment, while for those bio vector iterations in dio read's
endio, we now save a copy of bvec_iter in struct btrfs_io_bio when cloning
bios and use the helper __bio_for_each_segment with the saved bvec_iter to
access each bvec.
Also for dio reads which don't get split, we also need to save a copy of
bio iterator in btrfs_bio_clone to let __bio_for_each_segments to access
each bvec in dio read's endio. Note that it doesn't affect other calls of
btrfs_bio_clone() because they don't need to use this iterator.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently when mapping bio to limit bio to a single stripe length, we
split bio by adding page to bio one by one, but later we don't modify
the vector of bio at all, thus we can use bio_clone_fast to use the
original bio vector directly.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds a new helper btrfs_bio_clone_partial, it'll allocate a cloned
bio that only owns a part of the original bio's data.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For raid1 and raid10, we clone the original bio to the bios which are then
sent to different disks.
Right now we use bio_clone_bioset to create a clone bio with iterating
bi_io_vec to initialize it. This changes it to use bio_clone_fast()
which creates a clone bio but only copies the bi_io_vec pointer
instead of iterating bi_io_vec.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead pass around the failure tree and the io tree.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Once we remove the btree_inode we won't have an inode to pass anymore,
just pass the fs_info directly and the inum since we use that to print
out the repair message.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For extent_io tree's we have carried the address_mapping of the inode
around in the io tree in order to pull the inode back out for calling
into various tree ops hooks. This works fine when everything that has
an extent_io_tree has an inode. But we are going to remove the
btree_inode, so we need to change this. Instead just have a generic
void * for private data that we can initialize with, and have all the
tree ops use that instead. This had a lot of cascading changes but
should be relatively straightforward.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor reordering of the callback prototypes ]
Signed-off-by: David Sterba <dsterba@suse.com>
This patch adds the read-write attribute quota_override into sysfs.
Any process which has CAP_SYS_RESOURCE can set this flag to on, and
once it is set to true, processes with CAP_SYS_RESOURCE can exceed
the quota.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor changelog edits ]
Signed-off-by: David Sterba <dsterba@suse.com>
This patch introduces the quota override flag to btrfs_fs_info, and a
change to quota limit checking code to temporarily allow for quota to be
overridden for processes with CAP_SYS_RESOURCE.
It's useful for administrative programs, such as log rotation, that may
need to temporarily use more disk space in order to free up a greater
amount of overall disk space without yielding more disk space to the
rest of userland.
Eventually, we may want to add the idea of an operator-specific quota,
operator reserved space, or something else to allow for administrative
override, but this is perhaps the simplest solution.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor changelog edits ]
Signed-off-by: David Sterba <dsterba@suse.com>
The ->free_chunk_space variable is used to track the unallocated space
and access to it is protected by a spinlock, which is not used for
anything else. Make the code a bit self-explanatory by switching the
variable to an atomic64_t type and kill the spinlock.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
[ not a performance critical code, use of atomic type is ok ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds comments to the flush error handling part of the code, and
hopes to maintain the same logic with a framework which can be used to
handle the errors at the volume level.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These FIXMEs were already addressed in 2013. All functions check for
qgroup existence:
* btrfs_add_qgroup_relation
* btrfs_ioctl_qgroup_create
* btrfs_limit_qgroup
* btrfs_del_qgroup_relation
Signed-off-by: Daichou <tommy0705c@gmail.com>
[ enhance and reformat changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
Remove NULL test on kmap() as it will always return a valid pointer.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.
This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.
Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.
One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications. For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).
Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.
Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.
Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fixups from Zheng, prompted by the ongoing y2038 work.
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Merge tag 'ceph-for-4.12-rc6' of git://github.com/ceph/ceph-client
Pull ceph fixes from Ilya Dryomov:
"A fix for an old ceph ->fh_to_* bug from Luis and two timestamp fixups
from Zheng, prompted by the ongoing y2038 work"
* tag 'ceph-for-4.12-rc6' of git://github.com/ceph/ceph-client:
ceph: unify inode i_ctime update
ceph: use current_kernel_time() to get request time stamp
ceph: check i_nlink while converting a file handle to dentry
- Fix some bogus ASSERT failures on CONFIG_SMP=n and CONFIG_XFS_DEBUG=y.
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Merge tag 'xfs-4.12-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fix from Darrick Wong:
"One more bugfix for you for 4.12-rc6 to fix something that came up in
an earlier rc:
- Fix some bogus ASSERT failures on CONFIG_SMP=n and CONFIG_XFS_DEBUG=y"
* tag 'xfs-4.12-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix spurious spin_is_locked() assert failures on non-smp kernels
Pull ufs fixes from Al Viro:
"Fix assorted ufs bugs: a couple of deadlocks, fs corruption in
truncate(), oopsen on tail unpacking and truncate when racing with
vmscan, mild fs corruption (free blocks stats summary buggered, *BSD
fsck would complain and fix), several instances of broken logics
around reserved blocks (starting with "check almost never triggers
when it should" and then there are issues with sufficiently large
UFS2)"
[ Note: ufs hasn't gotten any loving in a long time, because nobody
really seems to use it. These ufs fixes are triggered by people
actually caring now, not some sudden influx of new bugs. - Linus ]
* 'ufs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ufs_truncate_blocks(): fix the case when size is in the last direct block
ufs: more deadlock prevention on tail unpacking
ufs: avoid grabbing ->truncate_mutex if possible
ufs_get_locked_page(): make sure we have buffer_heads
ufs: fix s_size/s_dsize users
ufs: fix reserved blocks check
ufs: make ufs_freespace() return signed
ufs: fix logics in "ufs: make fsck -f happy"
Pull vfs fixes from Al Viro:
"A couple of fixes; a leak in mntns_install() caught by Andrei (this
cycle regression) + d_invalidate() softlockup fix - that had been
reported by a bunch of people lately, but the problem is pretty old"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: don't forget to put old mntns in mntns_install
Hang/soft lockup in d_invalidate with simultaneous calls
Anon and hugetlbfs handle FOLL_DUMP set by get_dump_page() internally to
__get_user_pages().
shmem as opposed has no special FOLL_DUMP handling there so
handle_mm_fault() is invoked without mmap_sem and ends up calling
handle_userfault() that isn't expecting to be invoked without mmap_sem
held.
This makes handle_userfault() fail immediately if invoked through
shmem_vm_ops->fault during coredumping and solves the problem.
The side effect is a BUG_ON with no lock held triggered by the
coredumping process which exits. Only 4.11 is affected, pre-4.11 anon
memory holes are skipped in __get_user_pages by checking FOLL_DUMP
explicitly against empty pagetables (mm/gup.c:no_page_table()).
It's zero cost as we already had a check for current->flags to prevent
futex to trigger userfaults during exit (PF_EXITING).
Link: http://lkml.kernel.org/r/20170615214838.27429-1-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: <stable@vger.kernel.org> [4.11+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
And while I'm sending you this I'm also sneaking in a trivial new helper
from Bart so that we don't need inter-tree dependencies for the next merge
window.
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Merge tag 'configfs-for-4.12' of git://git.infradead.org/users/hch/configfs
Pull configfs updates from Christoph Hellwig:
"A fix from Nic for a race seen in production (including a stable tag).
And while I'm sending you this I'm also sneaking in a trivial new
helper from Bart so that we don't need inter-tree dependencies for the
next merge window"
* tag 'configfs-for-4.12' of git://git.infradead.org/users/hch/configfs:
configfs: Introduce config_item_get_unless_zero()
configfs: Fix race between create_link and configfs_rmdir
Fixes: 4f757f3cbf ("make sure that mntns_install() doesn't end up with referral for root")
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
It's not hard to trigger a bunch of d_invalidate() on the same
dentry in parallel. They end up fighting each other - any
dentry picked for removal by one will be skipped by the rest
and we'll go for the next iteration through the entire
subtree, even if everything is being skipped. Morevoer, we
immediately go back to scanning the subtree. The only thing
we really need is to dissolve all mounts in the subtree and
as soon as we've nothing left to do, we can just unhash the
dentry and bugger off.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull crypto fix from Herbert Xu:
"This fixes a bug on sparc where we may dereference freed stack memory"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: Work around deallocated stack frame reference gcc bug on sparc.
The logics when deciding whether we need to do anything with direct blocks
is broken when new size is within the last direct block. It's better to
find the path to the last byte _not_ to be removed and use that instead
of the path to the beginning of the first block to be freed...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
tail unpacking is done in a wrong place; the deadlocks galore
is best dealt with by doing that in ->write_iter() (and switching
to iomap, while we are at it), but that's rather painful to
backport. The trouble comes from grabbing pages that cover
the beginning of tail from inside of ufs_new_fragments(); ongoing
pageout of any of those is going to deadlock on ->truncate_mutex
with process that got around to extending the tail holding that
and waiting for page to get unlocked, while ->writepage() on
that page is waiting on ->truncate_mutex.
The thing is, we don't need ->truncate_mutex when the fragment
we are trying to map is within the tail - the damn thing is
allocated (tail can't contain holes).
Let's do a plain lookup and if the fragment is present, we can
just pretend that we'd won the race in almost all cases. The
only exception is a fragment between the end of tail and the
end of block containing tail.
Protect ->i_lastfrag with ->meta_lock - read_seqlock_excl() is
sufficient.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
callers rely upon that, but find_lock_page() racing with attempt of
page eviction by memory pressure might have left us with
* try_to_free_buffers() successfully done
* __remove_mapping() failed, leaving the page in our mapping
* find_lock_page() returning an uptodate page with no
buffer_heads attached.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
For UFS2 we need 64bit variants; we even store them in uspi, but
use 32bit ones instead. One wrinkle is in handling of reserved
space - recalculating it every time had been stupid all along, but
now it would become really ugly. Just calculate it once...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
a) honour ->s_minfree; don't just go with default (5)
b) don't bother with capability checks until we know we'll need them
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Liu Bo