The readahead framework is not on the critical writeback path we don't
need to use GFP_NOFS for allocations. All error paths are handled and
the readahead failures are not fatal. The actual users (scrub,
dev-replace) will trigger reads if the blocks are not found in cache.
Signed-off-by: David Sterba <dsterba@suse.com>
The send operation is not on the critical writeback path we don't need
to use GFP_NOFS for allocations. All error paths are handled and the
whole operation is restartable.
Signed-off-by: David Sterba <dsterba@suse.com>
Not needed after the previous patch named
"Btrfs: fix page reading in extent_same ioctl leading to csum errors".
Signed-off-by: Filipe Manana <fdmanana@suse.com>
In the extent_same ioctl, we were grabbing the pages (locked) and
attempting to read them without bothering about any concurrent IO
against them. That is, we were not checking for any ongoing ordered
extents nor waiting for them to complete, which leads to a race where
the extent_same() code gets a checksum verification error when it
reads the pages, producing a message like the following in dmesg
and making the operation fail to user space with -ENOMEM:
[18990.161265] BTRFS warning (device sdc): csum failed ino 259 off 495616 csum 685204116 expected csum 1515870868
Fix this by using btrfs_readpage() for reading the pages instead of
extent_read_full_page_nolock(), which waits for any concurrent ordered
extents to complete and locks the io range. Also do better error handling
and don't treat all failures as -ENOMEM, as that's clearly misleasing,
becoming identical to the checks and operation of prepare_uptodate_page().
The use of extent_read_full_page_nolock() was required before
commit f441460202 ("btrfs: fix deadlock with extent-same and readpage"),
as we had the range locked in an inode's io tree before attempting to
read the pages.
Fixes: f441460202 ("btrfs: fix deadlock with extent-same and readpage")
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
In the extent_same ioctl we are getting the pages for the source and
target ranges and unlocking them immediately after, which is incorrect
because later we attempt to map them (with kmap_atomic) and access their
contents at btrfs_cmp_data(). When we do such access the pages might have
been relocated or removed from memory, which leads to an invalid memory
access. This issue is detected on a kernel with CONFIG_DEBUG_PAGEALLOC=y
which produces a trace like the following:
186736.677437] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[186736.680382] Modules linked in: btrfs dm_flakey dm_mod ppdev xor raid6_pq sha256_generic hmac drbg ansi_cprng acpi_cpufreq evdev sg aesni_intel aes_x86_64
parport_pc ablk_helper tpm_tis psmouse parport i2c_piix4 tpm cryptd i2c_core lrw processor button serio_raw pcspkr gf128mul glue_helper loop autofs4 ext4
crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last
unloaded: btrfs]
[186736.681319] CPU: 13 PID: 10222 Comm: duperemove Tainted: G W 4.4.0-rc6-btrfs-next-18+ #1
[186736.681319] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[186736.681319] task: ffff880132600400 ti: ffff880362284000 task.ti: ffff880362284000
[186736.681319] RIP: 0010:[<ffffffff81264d00>] [<ffffffff81264d00>] memcmp+0xb/0x22
[186736.681319] RSP: 0018:ffff880362287d70 EFLAGS: 00010287
[186736.681319] RAX: 000002c002468acf RBX: 0000000012345678 RCX: 0000000000000000
[186736.681319] RDX: 0000000000001000 RSI: 0005d129c5cf9000 RDI: 0005d129c5cf9000
[186736.681319] RBP: ffff880362287d70 R08: 0000000000000000 R09: 0000000000001000
[186736.681319] R10: ffff880000000000 R11: 0000000000000476 R12: 0000000000001000
[186736.681319] R13: ffff8802f91d4c88 R14: ffff8801f2a77830 R15: ffff880352e83e40
[186736.681319] FS: 00007f27b37fe700(0000) GS:ffff88043dda0000(0000) knlGS:0000000000000000
[186736.681319] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[186736.681319] CR2: 00007f27a406a000 CR3: 0000000217421000 CR4: 00000000001406e0
[186736.681319] Stack:
[186736.681319] ffff880362287ea0 ffffffffa048d0bd 000000000009f000 0000000000001000
[186736.681319] 0100000000000000 ffff8801f2a77850 ffff8802f91d49b0 ffff880132600400
[186736.681319] 00000000000004f8 ffff8801c1efbe41 0000000000000000 0000000000000038
[186736.681319] Call Trace:
[186736.681319] [<ffffffffa048d0bd>] btrfs_ioctl+0x24cb/0x2731 [btrfs]
[186736.681319] [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[186736.681319] [<ffffffff8118b3d4>] ? rcu_read_unlock+0x3e/0x5d
[186736.681319] [<ffffffff811822f8>] do_vfs_ioctl+0x42b/0x4ea
[186736.681319] [<ffffffff8118b4f3>] ? __fget_light+0x62/0x71
[186736.681319] [<ffffffff8118240e>] SyS_ioctl+0x57/0x79
[186736.681319] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[186736.681319] Code: 0a 3c 6e 74 0d 3c 79 74 04 3c 59 75 0c c6 06 01 eb 03 c6 06 00 31 c0 eb 05 b8 ea ff ff ff 5d c3 55 31 c9 48 89 e5 48 39 d1 74 13 <0f> b6
04 0f 44 0f b6 04 0e 48 ff c1 44 29 c0 74 ea eb 02 31 c0
(gdb) list *(btrfs_ioctl+0x24cb)
0x5e0e1 is in btrfs_ioctl (fs/btrfs/ioctl.c:2972).
2967 dst_addr = kmap_atomic(dst_page);
2968
2969 flush_dcache_page(src_page);
2970 flush_dcache_page(dst_page);
2971
2972 if (memcmp(addr, dst_addr, cmp_len))
2973 ret = BTRFS_SAME_DATA_DIFFERS;
2974
2975 kunmap_atomic(addr);
2976 kunmap_atomic(dst_addr);
So fix this by making sure we keep the pages locked and respect the same
locking order as everywhere else: get and lock the pages first and then
lock the range in the inode's io tree (like for example at
__btrfs_buffered_write() and extent_readpages()). If an ordered extent
is found after locking the range in the io tree, unlock the range,
unlock the pages, wait for the ordered extent to complete and repeat the
entire locking process until no overlapping ordered extents are found.
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
In subpagesize-blocksize scenario, the "destination offset" argument passed to
the btrfs_ioctl_clone() can be aligned to sectorsize but may not be
necessarily aligned to the machine's page size. In such cases,
truncate_inode_pages_range() ends up zeroing out the partial page and future
read operations will return incorrect data. Hence this commit explicitly
rounds down the "destination offset" to the machine's page size.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When extending a file by either "truncate up" or by writing beyond i_size, the
page which had i_size needs to be marked "read only" so that future writes to
the page via mmap interface causes btrfs_page_mkwrite() to be invoked. If not,
a write performed after extending the file via the mmap interface will find
the page to be writaeable and continue writing to the page without invoking
btrfs_page_mkwrite() i.e. we end up writing to a file without reserving disk
space.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_getattr() returns PAGE_CACHE_SIZE as the block size. Since
generic_fillattr() already does the right thing (by obtaining block size
from inode->i_blkbits), just remove the statement from btrfs_getattr.
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
cow_file_range_inline() limits the size of an inline extent to
PAGE_CACHE_SIZE. This breaks in subpagesize-blocksize scenarios. Fix this by
comparing against root->sectorsize.
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In subpagesize-blocksize scenario, map_length can be less than the length of a
bio vector. Such a condition may cause btrfs_submit_direct_hook() to submit a
zero length bio. Fix this by comparing map_length against block size rather
than with bv_len.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In subpagesize-blocksize a page can map multiple extent buffers and hence
using (page index, seq) as the search key is incorrect. For example, searching
through tree modification log tree can return an entry associated with the
first extent buffer mapped by the page (if such an entry exists), when we are
actually searching for entries associated with extent buffers that are mapped
at position 2 or more in the page.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In subpagesize-blocksize scenario it is not sufficient to search using the
first byte of the page to make sure that there are no ordered extents
present across the page. Fix this.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In subpagesize-blocksize scenario, if i_size occurs in a block which is not
the last block in the page, then the space to be reserved should be calculated
appropriately.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
While at it, this commit changes btrfs_truncate_page() to truncate sectorsized
blocks instead of pages. Hence the function has been renamed to
btrfs_truncate_block().
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The direct I/O read's endio and corresponding repair functions work on
page sized blocks. This commit adds the ability for direct I/O read to work on
subpagesized blocks.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Checksums are applicable to sectorsize units. The current code uses
bio->bv_len units to compute and look up checksums. This works on machines
where sectorsize == PAGE_SIZE. This patch makes the checksum computation and
look up code to work with sectorsize units.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently, the code reserves/releases extents in multiples of PAGE_CACHE_SIZE
units. Fix this by doing reservation/releases in block size units.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
So the old one didn't work properly before alternatives had run.
And it was supposed to provide an optimized JMP because the
assumption was that the offset it is jumping to is within a
signed byte and thus a two-byte JMP.
So I did an x86_64 allyesconfig build and dumped all possible
sites where static_cpu_has() was used. The optimization amounted
to all in all 12(!) places where static_cpu_has() had generated
a 2-byte JMP. Which has saved us a whopping 36 bytes!
This clearly is not worth the trouble so we can remove it. The
only place where the optimization might count - in __switch_to()
- we will handle differently. But that's not subject of this
patch.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1453842730-28463-6-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull btrfs fixes from Chris Mason:
"Dave had a small collection of fixes to the new free space tree code,
one of which was keeping our sysfs files more up to date with feature
bits as different things get enabled (lzo, raid5/6, etc).
I should have kept the sysfs stuff for rc3, since we always manage to
trip over something. This time it was GFP_KERNEL from somewhere that
is NOFS only. Instead of rebasing it out I've put a revert in, and
we'll fix it properly for rc3.
Otherwise, Filipe fixed a btrfs DIO race and Qu Wenruo fixed up a
use-after-free in our tracepoints that Dave Jones reported"
* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Revert "btrfs: synchronize incompat feature bits with sysfs files"
btrfs: don't use GFP_HIGHMEM for free-space-tree bitmap kzalloc
btrfs: sysfs: check initialization state before updating features
Revert "btrfs: clear PF_NOFREEZE in cleaner_kthread()"
btrfs: async-thread: Fix a use-after-free error for trace
Btrfs: fix race between fsync and lockless direct IO writes
btrfs: add free space tree to the cow-only list
btrfs: add free space tree to lockdep classes
btrfs: tweak free space tree bitmap allocation
btrfs: tests: switch to GFP_KERNEL
btrfs: synchronize incompat feature bits with sysfs files
btrfs: sysfs: introduce helper for syncing bits with sysfs files
btrfs: sysfs: add free-space-tree bit attribute
btrfs: sysfs: fix typo in compat_ro attribute definition
This reverts commit 14e46e0495.
This ends up doing sysfs operations from deep in balance (where we
should be GFP_NOFS) and under heavy balance load, we're making races
against sysfs internals.
Revert it for now while we figure things out.
Signed-off-by: Chris Mason <clm@fb.com>
If the mount phase is not finished, we can't update the sysfs files.
Reported-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Parameter of trace_btrfs_work_queued() can be freed in its workqueue.
So no one use use that pointer after queue_work().
Fix the user-after-free bug by move the trace line before queue_work().
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
An fsync, using the fast path, can race with a concurrent lockless direct
IO write and end up logging a file extent item that points to an extent
that wasn't written to yet. This is because the fast fsync path collects
ordered extents into a local list and then collects all the new extent
maps to log file extent items based on them, while the direct IO write
path creates the new extent map before it creates the corresponding
ordered extent (and submitting the respective bio(s)).
So fix this by making the direct IO write path create ordered extents
before the extent maps and make the fast fsync path collect any new
ordered extents after it collects the extent maps.
Note that making the fsync handler call inode_dio_wait() (after acquiring
the inode's i_mutex) would not work and lead to a deadlock when doing
AIO, as through AIO we end up in a path where the fsync handler is called
(through dio_aio_complete_work() -> dio_complete() -> vfs_fsync_range())
before the inode's dio counter is decremented (inode_dio_wait() waits
for this counter to have a value of zero).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).
Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull more btrfs updates from Chris Mason:
"These are mostly fixes that we've been testing, but also we grabbed
and tested a few small cleanups that had been on the list for a while.
Zhao Lei's patchset also fixes some early ENOSPC buglets"
* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (21 commits)
btrfs: raid56: Use raid_write_end_io for scrub
btrfs: Remove unnecessary ClearPageUptodate for raid56
btrfs: use rbio->nr_pages to reduce calculation
btrfs: Use unified stripe_page's index calculation
btrfs: Fix calculation of rbio->dbitmap's size calculation
btrfs: Fix no_space in write and rm loop
btrfs: merge functions for wait snapshot creation
btrfs: delete unused argument in btrfs_copy_from_user
btrfs: Use direct way to determine raid56 write/recover mode
btrfs: Small cleanup for get index_srcdev loop
btrfs: Enhance chunk validation check
btrfs: Enhance super validation check
Btrfs: fix deadlock running delayed iputs at transaction commit time
Btrfs: fix typo in log message when starting a balance
btrfs: remove duplicate const specifier
btrfs: initialize the seq counter in struct btrfs_device
Btrfs: clean up an error code in btrfs_init_space_info()
btrfs: fix iterator with update error in backref.c
Btrfs: fix output of compression message in btrfs_parse_options()
Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots
...
The requested bitmap size varies, observed numbers were < 4K up to 16K.
Using vmalloc unconditionally would be too heavy, we'll try contiguous
allocations first and fall back to vmalloc if there's no contig memory.
Signed-off-by: David Sterba <dsterba@suse.com>
There's no reason to do GFP_NOFS in tests, it's not data-heavy and
memory allocation failures would affect only developers or testers.
Signed-off-by: David Sterba <dsterba@suse.com>
The files under /sys/fs/UUID/features get out of sync with the actual
incompat bits set for the filesystem if they change after mount (eg. the
LZO compression).
Synchronize the feature bits with the sysfs files representing them
right after we set/clear them.
Signed-off-by: David Sterba <dsterba@suse.com>
The files under /sys/fs/UUID/features get out of sync with the actual
incompat bits set for the filesystem if they change after mount. We're
going to sync them and need a helper to do that.
Signed-off-by: David Sterba <dsterba@suse.com>
The incompat bit representing the newly added free space tree feature is
missing. Right now it will be listed only among features supported by
the module, not per-fs.
Signed-off-by: David Sterba <dsterba@suse.com>
No need to create additional end_io function for scrub, it increased
code size and introduced some un-unified lines, as:
raid_write_parity_end_io():
int err = bio->bi_error;
if (bio->bi_error)
raid_write_end_io():
int err = bio->bi_error;
if (err)
This patch combines them.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
PageUptodate flag already initialized to 0 for new page,
no need to set it again.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We can use rbio->stripe_npages to reduce unnecessary calculation in
many code place.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We are using different index calculation method for stripe_page in
current code:
1: (rbio->stripe_len / PAGE_CACHE_SIZE) * stripe_index + page_index
2: DIV_ROUND_UP(rbio->stripe_len, PAGE_CACHE_SIZE) * stripe_index + page_index
3: DIV_ROUND_UP(rbio->stripe_len * stripe_index, PAGE_CACHE_SIZE) + page_index
...
They can get same result when stripe_len align to PAGE_CACHE_SIZE,
this is why current code can work, intruduce and use a common function
for calculation is a better choose.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Current code is trying to calculate rbio->dbitmap's size to make it
align to sizeof(long), but implement haven't achived this object,
it is align to sizeof(char) instead.
This patch fixed above calculation, and use sizeof(long) instead of
fixed "8" to increate compatibility.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
I see no_space in v4.4-rc1 again in xfstests generic/102.
It happened randomly in some node only.
(one of 4 phy-node, and a kvm with non-virtio block driver)
By bisect, we can found the first-bad is:
commit bdced438ac ("block: setup bi_phys_segments after splitting")'
But above patch only triggered the bug by making bio operation
faster(or slower).
Main reason is in our space_allocating code, we need to commit
page writeback before wait it complish, this patch fixed above
bug.
BTW, there is another reason for generic/102 fail, caused by
disable default mixed-blockgroup, I'll fix it in xfstests.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
wait_for_snapshot_creation() is in same group with oher two:
btrfs_start_write_no_snapshoting()
btrfs_end_write_no_snapshoting()
Rename wait_for_snapshot_creation() and move it into same place
with other two.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
size_t write_bytes is not necessary for btrfs_copy_from_user(),
delete it.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Old code used bbio->raid_map to determine whether in raid56
write/recover operation, because we didn't't have bbio->map_type.
Now we have direct way for this condition, rid of using
the function-relative data, and make the code more readable.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
1: Adjust condition in loop to make less TAB
2: Move btrfs_put_bbio()'s line for combine, and makes logic clean.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Enhance chunk validation:
1) Num_stripes
We already have such check but it's only in super block sys chunk
array.
Now check all on-disk chunks.
2) Chunk logical
It should be aligned to sector size.
This behavior should be *DOUBLE CHECKED* for 64K sector size like
PPC64 or AArch64.
Maybe we can found some hidden bugs.
3) Chunk length
Same as chunk logical, should be aligned to sector size.
4) Stripe length
It should be power of 2.
5) Chunk type
Any bit out of TYPE_MAS | PROFILE_MASK is invalid.
With all these much restrict rules, several fuzzed image reported in
mail list should no longer cause kernel panic.
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Enhance btrfs_check_super_valid() function by the following points:
1) Restrict sector/node size check
Not the old max/min valid check, but also check if it's a power of 2.
So some bogus number like 12K node size won't pass now.
2) Super flag check
For now, there is still some inconsistency between kernel and
btrfs-progs super flags.
And considering btrfs-progs may add new flags for super block, this
check will only output warning.
3) Better root alignment check
Now root bytenr is checked against sector size.
4) Move some check into btrfs_check_super_valid().
Like node size vs leaf size check, and PAGESIZE vs sectorsize check.
And magic number check.
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
