The value of item_size of struct btrfs_clone_extent_info is always set to
the size of a non-inline file extent item, and in fact the infrastructure
that uses this structure (btrfs_punch_hole_range()) does not work with
inline file extents at all (and it is not supposed to).
So just remove that field from the structure and use directly
sizeof(struct btrfs_file_extent_item) instead. Also assert that the
file extent type is not inline at btrfs_insert_clone_extent().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When doing an fallocate(), specially a zero range operation, we assume
that reserving 3 units of metadata space is enough, that at most we touch
one leaf in subvolume/fs tree for removing existing file extent items and
inserting a new file extent item. This assumption is generally true for
most common use cases. However when we end up needing to remove file extent
items from multiple leaves, we can end up failing with -ENOSPC and abort
the current transaction, turning the filesystem to RO mode. When this
happens a stack trace like the following is dumped in dmesg/syslog:
[ 1500.620934] ------------[ cut here ]------------
[ 1500.620938] BTRFS: Transaction aborted (error -28)
[ 1500.620973] WARNING: CPU: 2 PID: 30807 at fs/btrfs/inode.c:9724 __btrfs_prealloc_file_range+0x512/0x570 [btrfs]
[ 1500.620974] Modules linked in: btrfs intel_rapl_msr intel_rapl_common kvm_intel (...)
[ 1500.621010] CPU: 2 PID: 30807 Comm: xfs_io Tainted: G W 5.9.0-rc3-btrfs-next-67 #1
[ 1500.621012] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[ 1500.621023] RIP: 0010:__btrfs_prealloc_file_range+0x512/0x570 [btrfs]
[ 1500.621026] Code: 8b 40 50 f0 48 (...)
[ 1500.621028] RSP: 0018:ffffb05fc8803ca0 EFLAGS: 00010286
[ 1500.621030] RAX: 0000000000000000 RBX: ffff9608af276488 RCX: 0000000000000000
[ 1500.621032] RDX: 0000000000000001 RSI: 0000000000000027 RDI: 00000000ffffffff
[ 1500.621033] RBP: ffffb05fc8803d90 R08: 0000000000000001 R09: 0000000000000001
[ 1500.621035] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000003200000
[ 1500.621037] R13: 00000000ffffffe4 R14: ffff9608af275fe8 R15: ffff9608af275f60
[ 1500.621039] FS: 00007fb5b2368ec0(0000) GS:ffff9608b6600000(0000) knlGS:0000000000000000
[ 1500.621041] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1500.621043] CR2: 00007fb5b2366fb8 CR3: 0000000202d38005 CR4: 00000000003706e0
[ 1500.621046] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1500.621047] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1500.621049] Call Trace:
[ 1500.621076] btrfs_prealloc_file_range+0x10/0x20 [btrfs]
[ 1500.621087] btrfs_fallocate+0xccd/0x1280 [btrfs]
[ 1500.621108] vfs_fallocate+0x14d/0x290
[ 1500.621112] ksys_fallocate+0x3a/0x70
[ 1500.621117] __x64_sys_fallocate+0x1a/0x20
[ 1500.621120] do_syscall_64+0x33/0x80
[ 1500.621123] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 1500.621126] RIP: 0033:0x7fb5b248c477
[ 1500.621128] Code: 89 7c 24 08 (...)
[ 1500.621130] RSP: 002b:00007ffc7bee9060 EFLAGS: 00000293 ORIG_RAX: 000000000000011d
[ 1500.621132] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fb5b248c477
[ 1500.621134] RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000003
[ 1500.621136] RBP: 0000557718faafd0 R08: 0000000000000000 R09: 0000000000000000
[ 1500.621137] R10: 0000000003200000 R11: 0000000000000293 R12: 0000000000000010
[ 1500.621139] R13: 0000557718faafb0 R14: 0000557718faa480 R15: 0000000000000003
[ 1500.621151] irq event stamp: 1026217
[ 1500.621154] hardirqs last enabled at (1026223): [<ffffffffba965570>] console_unlock+0x500/0x5c0
[ 1500.621156] hardirqs last disabled at (1026228): [<ffffffffba9654c7>] console_unlock+0x457/0x5c0
[ 1500.621159] softirqs last enabled at (1022486): [<ffffffffbb6003dc>] __do_softirq+0x3dc/0x606
[ 1500.621161] softirqs last disabled at (1022477): [<ffffffffbb4010b2>] asm_call_on_stack+0x12/0x20
[ 1500.621162] ---[ end trace 2955b08408d8b9d4 ]---
[ 1500.621167] BTRFS: error (device sdj) in __btrfs_prealloc_file_range:9724: errno=-28 No space left
When we use fallocate() internally, for reserving an extent for a space
cache, inode cache or relocation, we can't hit this problem since either
there aren't any file extent items to remove from the subvolume tree or
there is at most one.
When using plain fallocate() it's very unlikely, since that would require
having many file extent items representing holes for the target range and
crossing multiple leafs - we attempt to increase the range (merge) of such
file extent items when punching holes, so at most we end up with 2 file
extent items for holes at leaf boundaries.
However when using the zero range operation of fallocate() for a large
range (100+ MiB for example) that's fairly easy to trigger. The following
example reproducer triggers the issue:
$ cat reproducer.sh
#!/bin/bash
umount /dev/sdj &> /dev/null
mkfs.btrfs -f -n 16384 -O ^no-holes /dev/sdj > /dev/null
mount /dev/sdj /mnt/sdj
# Create a 100M file with many file extent items. Punch a hole every 8K
# just to speedup the file creation - we could do 4K sequential writes
# followed by fsync (or O_SYNC) as well, but that takes a lot of time.
file_size=$((100 * 1024 * 1024))
xfs_io -f -c "pwrite -S 0xab -b 10M 0 $file_size" /mnt/sdj/foobar
for ((i = 0; i < $file_size; i += 8192)); do
xfs_io -c "fpunch $i 4096" /mnt/sdj/foobar
done
# Force a transaction commit, so the zero range operation will be forced
# to COW all metadata extents it need to touch.
sync
xfs_io -c "fzero 0 $file_size" /mnt/sdj/foobar
umount /mnt/sdj
$ ./reproducer.sh
wrote 104857600/104857600 bytes at offset 0
100 MiB, 10 ops; 0.0669 sec (1.458 GiB/sec and 149.3117 ops/sec)
fallocate: No space left on device
$ dmesg
<shows the same stack trace pasted before>
To fix this use the existing infrastructure that hole punching and
extent cloning use for replacing a file range with another extent. This
deals with doing the removal of file extent items and inserting the new
one using an incremental approach, reserving more space when needed and
always ensuring we don't leave an implicit hole in the range in case
we need to do multiple iterations and a crash happens between iterations.
A test case for fstests will follow up soon.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It is not used since commit 0096420adb ("btrfs: do not
account global reserve in can_overcommit").
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function is short and simple, we can get rid of the declaration as
it's not necessary for a static function. Move it before its first
caller. No functional changes.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function does not have a common exit block and returns immediatelly
so there's no point having the goto. Remove the two cases.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We can check the argument value directly, no need for the temporary
variable.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the function btrfs_init_dev_replace_tgtdev(), the local variable
devices is used only once, we can remove it.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
On a mounted sprout filesystem, all threads now are using the
sprout::device_list_mutex, and this is the only code using the
seed::device_list_mutex. This patch converts to use the sprouts
fs_info->fs_devices->device_list_mutex.
The same reasoning holds true here, that device delete is holding
the sprout::device_list_mutex.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
On an fs mounted using a sprout device, the seed fs_devices are
maintained in a linked list under fs_info->fs_devices. Each seeds
fs_devices also has device_list_mutex initialized to protect against the
potential race with delete threads. But the delete thread (at
btrfs_rm_device()) is holding the fs_info::fs_devices::device_list_mutex
mutex which belongs to sprout device_list_mutex instead of seed
device_list_mutex. Moreover, there aren't any significient benefits in
using the seed::device_list_mutex instead of sprout::device_list_mutex.
So this patch converts them of using the seed::device_list_mutex to
sprout::device_list_mutex.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_sysfs_add_fs_devices() is called by btrfs_sysfs_add_mounted().
btrfs_sysfs_add_mounted() assumes that btrfs_sysfs_add_fs_devices() will
either add sysfs entries for all the devices or none. So this patch keeps up
to its caller expecatation and cleans up the created sysfs entries if it
has to fail at some device in the list.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We don't initialize the sysfs devid kobject and device-link yet for the
seed devices in an sprouted filesystem.
So this patch initializes the seed device devid kobject and the device
link in the sysfs.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Similar to btrfs_sysfs_add_devices_dir()'s refactoring, split
btrfs_sysfs_remove_devices_dir() so that we don't have to use the device
argument to indicate whether to free all devices or just one device.
Export btrfs_sysfs_remove_device() as device operations outside of
sysfs.c now calls this instead of btrfs_sysfs_remove_devices_dir().
btrfs_sysfs_remove_devices_dir() is renamed to
btrfs_sysfs_remove_fs_devices() to suite its new role.
Now, no one outside of sysfs.c calls btrfs_sysfs_remove_fs_devices()
so it is redeclared s static. And the same function had to be moved
before its first caller.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we add a device we need to add it to sysfs, so instead of using the
btrfs_sysfs_add_devices_dir() fs_devices argument to specify whether to
add a device or all of fs_devices, call the helper function directly
btrfs_sysfs_add_device() and thus make it non-static.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_sysfs_remove_devices_dir() return value is unused declare it as
void.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_sysfs_remove_devices_dir() removes device link and devid kobject
(sysfs entries) for a device or all the devices in the btrfs_fs_devices.
In preparation to remove these sysfs entries for the seed as well, add
a btrfs_sysfs_remove_device() helper function and avoid code
duplication.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_sysfs_add_devices_dir() adds device link and devid kobject
(sysfs entries) for a device or all the devices in the btrfs_fs_devices.
In preparation to add these sysfs entries for the seed as well, add
a btrfs_sysfs_add_device() helper function and avoid code duplication.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If you replace a seed device in a sprouted fs, it appears to have
successfully replaced the seed device, but if you look closely, it
didn't. Here is an example.
$ mkfs.btrfs /dev/sda
$ btrfstune -S1 /dev/sda
$ mount /dev/sda /btrfs
$ btrfs device add /dev/sdb /btrfs
$ umount /btrfs
$ btrfs device scan --forget
$ mount -o device=/dev/sda /dev/sdb /btrfs
$ btrfs replace start -f /dev/sda /dev/sdc /btrfs
$ echo $?
0
BTRFS info (device sdb): dev_replace from /dev/sda (devid 1) to /dev/sdc started
BTRFS info (device sdb): dev_replace from /dev/sda (devid 1) to /dev/sdc finished
$ btrfs fi show
Label: none uuid: ab2c88b7-be81-4a7e-9849-c3666e7f9f4f
Total devices 2 FS bytes used 256.00KiB
devid 1 size 3.00GiB used 520.00MiB path /dev/sdc
devid 2 size 3.00GiB used 896.00MiB path /dev/sdb
Label: none uuid: 10bd3202-0415-43af-96a8-d5409f310a7e
Total devices 1 FS bytes used 128.00KiB
devid 1 size 3.00GiB used 536.00MiB path /dev/sda
So as per the replace start command and kernel log replace was successful.
Now let's try to clean mount.
$ umount /btrfs
$ btrfs device scan --forget
$ mount -o device=/dev/sdc /dev/sdb /btrfs
mount: /btrfs: wrong fs type, bad option, bad superblock on /dev/sdb, missing codepage or helper program, or other error.
[ 636.157517] BTRFS error (device sdc): failed to read chunk tree: -2
[ 636.180177] BTRFS error (device sdc): open_ctree failed
That's because per dev items it is still looking for the original seed
device.
$ btrfs inspect-internal dump-tree -d /dev/sdb
item 0 key (DEV_ITEMS DEV_ITEM 1) itemoff 16185 itemsize 98
devid 1 total_bytes 3221225472 bytes_used 545259520
io_align 4096 io_width 4096 sector_size 4096 type 0
generation 6 start_offset 0 dev_group 0
seek_speed 0 bandwidth 0
uuid 59368f50-9af2-4b17-91da-8a783cc418d4 <--- seed uuid
fsid 10bd3202-0415-43af-96a8-d5409f310a7e <--- seed fsid
item 1 key (DEV_ITEMS DEV_ITEM 2) itemoff 16087 itemsize 98
devid 2 total_bytes 3221225472 bytes_used 939524096
io_align 4096 io_width 4096 sector_size 4096 type 0
generation 0 start_offset 0 dev_group 0
seek_speed 0 bandwidth 0
uuid 56a0a6bc-4630-4998-8daf-3c3030c4256a <- sprout uuid
fsid ab2c88b7-be81-4a7e-9849-c3666e7f9f4f <- sprout fsid
But the replaced target has the following uuid+fsid in its superblock
which doesn't match with the expected uuid+fsid in its devitem.
$ btrfs in dump-super /dev/sdc | egrep '^generation|dev_item.uuid|dev_item.fsid|devid'
generation 20
dev_item.uuid 59368f50-9af2-4b17-91da-8a783cc418d4
dev_item.fsid ab2c88b7-be81-4a7e-9849-c3666e7f9f4f [match]
dev_item.devid 1
So if you provide the original seed device the mount shall be
successful. Which so long happening in the test case btrfs/163.
$ btrfs device scan --forget
$ mount -o device=/dev/sda /dev/sdb /btrfs
Fix in this patch:
If a seed is not sprouted then there is no replacement of it, because of
its read-only filesystem with a read-only device. Similarly, in the case
of a sprouted filesystem, the seed device is still read only. So, mark
it as you can't replace a seed device, you can only add a new device and
then delete the seed device. If replace is attempted then returns
-EINVAL.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Systems booting without the initramfs seems to scan an unusual kind
of device path (/dev/root). And at a later time, the device is updated
to the correct path. We generally print the process name and PID of the
process scanning the device but we don't capture the same information if
the device path is rescanned with a different pathname.
The current message is too long, so drop the unnecessary UUID and add
process name and PID.
While at this also update the duplicate device warning to include the
process name and PID so the messages are consistent
CC: stable@vger.kernel.org # 4.19+
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=89721
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
I'm a actual human being so am incapable of converting u64 to s64 in my
head, so add a helper to get the pretty name of a root objectid and use
that helper to spit out the name for any special roots for leaked roots,
so I don't have to scratch my head and figure out which root I messed up
the refs for.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
/sys/fs/<fsid>/exclusive_operation contains the currently executing
exclusive operation. Add a sysfs_notify() when operation end, so
userspace can be notified of exclusive operation is finished.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of using a flag bit for exclusive operation, use a variable to
store which exclusive operation is being performed. Introduce an API
to start and finish an exclusive operation.
This would enable another way for tools to check which operation is
running on why starting an exclusive operation failed. The followup
patch adds a sysfs_notify() to alert userspace when the state changes, so
userspace can perform select() on it to get notified of the change.
This would enable us to enqueue a command which will wait for current
exclusive operation to complete before issuing the next exclusive
operation. This has been done synchronously as opposed to a background
process, or else error collection (if any) will become difficult.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's counterintuitive to have a function named btrfs_inode_xxx which
takes a generic inode. Also move the function to btrfs_inode.h so that
it has access to the definition of struct btrfs_inode.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
I've made this change separate since it requires both of the newly added
NESTED flags and I didn't want to slip it into one of those changes.
If we do a double split of a node we can end up doing a
BTRFS_NESTED_SPLIT on level 0, which throws lockdep off because it
appears as a double lock. Since we're maxed out on subclasses, use
BTRFS_NESTED_NEW_ROOT if we had to do a double split. This is OK
because we won't have to do a double split if we had to insert a new
root, and the new root would be at a higher level anyway.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The way we add new roots is confusing from a locking perspective for
lockdep. We generally have the rule that we lock things in order from
highest level to lowest, but in the case of adding a new level to the
tree we actually allocate a new block for the root, which makes the
locking go in reverse. A similar issue exists for snapshotting, we cow
the original root for the root of a new tree, however they're at the
same level. Address this by using BTRFS_NESTING_NEW_ROOT for these
operations.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If we are splitting a leaf/node, we could do something like the
following
lock(leaf) BTRFS_NESTING_NORMAL
lock(left) BTRFS_NESTING_LEFT + BTRFS_NESTING_COW
push from leaf -> left
reset path to point to left
split left
allocate new block, lock block BTRFS_NESTING_SPLIT
at the new block point we need to have a different nesting level,
because we have already used either BTRFS_NESTING_LEFT or
BTRFS_NESTING_RIGHT when pushing items from the original leaf into the
adjacent leaves.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For similar reasons as BTRFS_NESTING_COW, we need
BTRFS_NESTING_LEFT/RIGHT_COW. The pattern is this
lock leaf -> BTRFS_NESTING_NORMAL
cow leaf -> BTRFS_NESTING_COW
split leaf
lock left -> BTRFS_NESTING_LEFT
cow left -> BTRFS_NESTING_LEFT_COW
We need this in order to indicate to lockdep that these locks are
discrete and are being taken in a safe order.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Our lockdep maps are based on rootid+level, however in some cases we
will lock adjacent blocks on the same level, namely in searching forward
or in split/balance. Because of this lockdep will complain, so we need
a separate subclass to indicate to lockdep that these are different
locks.
lock leaf -> BTRFS_NESTING_NORMAL
cow leaf -> BTRFS_NESTING_COW
split leaf
lock left -> BTRFS_NESTING_LEFT
lock right -> BTRFS_NESTING_RIGHT
The above graph illustrates the need for this new nesting subclass.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we COW a block we are holding a lock on the original block, and
then we lock the new COW block. Because our lockdep maps are based on
root + level, this will make lockdep complain. We need a way to
indicate a subclass for locking the COW'ed block, so plumb through our
btrfs_lock_nesting from btrfs_cow_block down to the btrfs_init_buffer,
and then introduce BTRFS_NESTING_COW to be used for cow'ing blocks.
The reason I've added all this extra infrastructure is because there
will be need of different nesting classes in follow up patches.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We will need these when we switch to an rwsem, so plumb in the
infrastructure here to use later on. I violate the 80 character limit
some here because it'll be cleaned up later.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Our current tree locking stuff allows us to recurse with read locks if
we're already holding the write lock. This is necessary for the space
cache inode, as we could be holding a lock on the root_tree root when we
need to cache a block group, and thus need to be able to read down the
root_tree to read in the inode cache.
We can get away with this in our current locking, but we won't be able
to with a rwsem. Handle this by purposefully annotating the places
where we require recursion, so that in the future we can maybe come up
with a way to avoid the recursion. In the case of the free space inode,
this will be superseded by the free space tree.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Nested locking with lockdep and everything else refers to lock hierarchy
within the same lock map. This is how we indicate the same locks for
different objects are ok to take in a specific order, for our use case
that would be to take the lock on a leaf and then take a lock on an
adjacent leaf.
What ->lock_nested _actually_ refers to is if we happen to already be
holding the write lock on the extent buffer and we're allowing a read
lock to be taken on that extent buffer, which is recursion. Rename this
so we don't get confused when we switch to a rwsem and have to start
using the _nested helpers.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of opencoding filemap_write_and_wait simply call syncblockdev as
it makes it abundantly clear what's going on and why this is used. No
semantics changes.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Following the refactor of btrfs_free_stale_devices in
7bcb8164ad ("btrfs: use device_list_mutex when removing stale devices")
fs_devices are freed after they have been iterated by the inner
list_for_each so the use-after-free fixed by introducing the break in
fd649f10c3 ("btrfs: Fix use-after-free when cleaning up fs_devs with
a single stale device") is no longer necessary. Just remove it
altogether. No functional changes.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Invert unlocked to locked and exploit the fact it can only ever be
modified if we are adding a new device to a seed filesystem. This allows
to simplify the check in error: label. No semantics changes.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When adding a new device there's a mandatory check to see if a device is
being duplicated to the filesystem it's added to. Since this is a
read-only operations not necessary to take device_list_mutex and can simply
make do with an rcu-readlock.
Using just RCU is safe because there won't be another device add delete
running in parallel as btrfs_init_new_device is called only from
btrfs_ioctl_add_dev.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
With a crafted image, btrfs can panic at btrfs_del_csums():
kernel BUG at fs/btrfs/ctree.c:3188!
invalid opcode: 0000 [#1] SMP PTI
CPU: 0 PID: 1156 Comm: btrfs-transacti Not tainted 5.0.0-rc8+ #9
RIP: 0010:btrfs_set_item_key_safe+0x16c/0x180
RSP: 0018:ffff976141257ab8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff898a6b890930 RCX: 0000000004b70000
RDX: 0000000000000000 RSI: ffff976141257bae RDI: ffff976141257acf
RBP: ffff976141257b10 R08: 0000000000001000 R09: ffff9761412579a8
R10: 0000000000000000 R11: 0000000000000000 R12: ffff976141257abe
R13: 0000000000000003 R14: ffff898a6a8be578 R15: ffff976141257bae
FS: 0000000000000000(0000) GS:ffff898a77a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f779d9cd624 CR3: 000000022b2b4006 CR4: 00000000000206f0
Call Trace:
truncate_one_csum+0xac/0xf0
btrfs_del_csums+0x24f/0x3a0
__btrfs_free_extent.isra.72+0x5a7/0xbe0
__btrfs_run_delayed_refs+0x539/0x1120
btrfs_run_delayed_refs+0xdb/0x1b0
btrfs_commit_transaction+0x52/0x950
? start_transaction+0x94/0x450
transaction_kthread+0x163/0x190
kthread+0x105/0x140
? btrfs_cleanup_transaction+0x560/0x560
? kthread_destroy_worker+0x50/0x50
ret_from_fork+0x35/0x40
Modules linked in:
---[ end trace 93bf9db00e6c374e ]---
[CAUSE]
This crafted image has a tricky key order corruption:
checksum tree key (CSUM_TREE ROOT_ITEM 0)
node 29741056 level 1 items 14 free 107 generation 19 owner CSUM_TREE
...
key (EXTENT_CSUM EXTENT_CSUM 73785344) block 29757440 gen 19
key (EXTENT_CSUM EXTENT_CSUM 77594624) block 29753344 gen 19
...
leaf 29757440 items 5 free space 150 generation 19 owner CSUM_TREE
item 0 key (EXTENT_CSUM EXTENT_CSUM 73785344) itemoff 2323 itemsize 1672
range start 73785344 end 75497472 length 1712128
item 1 key (EXTENT_CSUM EXTENT_CSUM 75497472) itemoff 2319 itemsize 4
range start 75497472 end 75501568 length 4096
item 2 key (EXTENT_CSUM EXTENT_CSUM 75501568) itemoff 579 itemsize 1740
range start 75501568 end 77283328 length 1781760
item 3 key (EXTENT_CSUM EXTENT_CSUM 77283328) itemoff 575 itemsize 4
range start 77283328 end 77287424 length 4096
item 4 key (EXTENT_CSUM EXTENT_CSUM 4120596480) itemoff 275 itemsize 300 <<<
range start 4120596480 end 4120903680 length 307200
leaf 29753344 items 3 free space 1936 generation 19 owner CSUM_TREE
item 0 key (18446744073457893366 EXTENT_CSUM 77594624) itemoff 2323 itemsize 1672
range start 77594624 end 79306752 length 1712128
...
Note the item 4 key of leaf 29757440, which is obviously too large, and
even larger than the first key of the next leaf.
However it still follows the key order in that tree block, thus tree
checker is unable to detect it at read time, since tree checker can only
work inside one leaf, thus such complex corruption can't be detected in
advance.
[FIX]
The next time to detect such problem is at tree block merge time,
which is in push_node_left(), balance_node_right(), push_leaf_left() or
push_leaf_right().
Now we check if the key order of the right-most key of the left node is
larger than the left-most key of the right node.
By this we don't need to call the full tree-checker, while still keeping
the key order correct as key order in each node is already checked by
tree checker thus we only need to check the above two slots.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202833
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
With a crafted image, btrfs can panic at insert_inline_extent_backref():
kernel BUG at fs/btrfs/extent-tree.c:1857!
invalid opcode: 0000 [#1] SMP PTI
CPU: 0 PID: 1117 Comm: btrfs-transacti Not tainted 5.0.0-rc8+ #9
RIP: 0010:insert_inline_extent_backref+0xcc/0xe0
RSP: 0018:ffffac4dc1287be8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000000001
RDX: 0000000000001000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffac4dc1287c28 R08: ffffac4dc1287ab8 R09: ffffac4dc1287ac0
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8febef88a540 R14: ffff8febeaa7bc30 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8febf7a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f663ace94c0 CR3: 0000000235698006 CR4: 00000000000206f0
Call Trace:
? _cond_resched+0x1a/0x50
__btrfs_inc_extent_ref.isra.64+0x7e/0x240
? btrfs_merge_delayed_refs+0xa5/0x330
__btrfs_run_delayed_refs+0x653/0x1120
btrfs_run_delayed_refs+0xdb/0x1b0
btrfs_commit_transaction+0x52/0x950
? start_transaction+0x94/0x450
transaction_kthread+0x163/0x190
kthread+0x105/0x140
? btrfs_cleanup_transaction+0x560/0x560
? kthread_destroy_worker+0x50/0x50
ret_from_fork+0x35/0x40
Modules linked in:
---[ end trace 2ad8b3de903cf825 ]---
[CAUSE]
Due to extent tree corruption (still valid by itself, but bad cross
ref), we can allocate an extent which is still in extent tree. The
offending tree block of that case is from csum tree. The newly
allocated tree block is also for csum tree.
Then we will try to insert a tree block ref for the existing tree block
ref.
For a tree extent item, tree block can never be shared directly by the
same tree twice. We have such BUG_ON() to prevent such problem, but
this is not a proper error handling.
[FIX]
Replace that BUG_ON() with proper error message and leaf dump for debug
build.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202829
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
__btrfs_free_extent() is doing two things:
1. Reduce the refs number of an extent backref
Either it's an inline extent backref (inside EXTENT/METADATA item) or
a keyed extent backref (SHARED_* item).
We only need to locate that backref line, either reduce the number or
remove the backref line completely.
2. Update the refs count in EXTENT/METADATA_ITEM
During step 1), we will try to locate the EXTENT/METADATA_ITEM without
triggering another btrfs_search_slot() as fast path.
Only when we fail to locate that item, we will trigger another
btrfs_search_slot() to get that EXTENT/METADATA_ITEM after we
updated/deleted the backref line.
And we have a lot of strict checks on things like refs_to_drop against
extent refs and special case checks for single ref extents.
There are 7 BUG_ON()s, although they're doing correct checks, they can
be triggered by crafted images.
This patch improves the function:
- Introduce two examples to show what __btrfs_free_extent() is doing
One inline backref case and one keyed case. Should cover most cases.
- Kill all BUG_ON()s with proper error message and optional leaf dump
- Add comment to show the overall flow
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202819
[ The report triggers one BUG_ON() in __btrfs_free_extent() ]
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
