The problem of long mount time caused by block group item search is
already known for some time, and the solution of block group tree has
been proposed.
There is really no need to bound this feature into extent tree v2, just
introduce compat RO flag, BLOCK_GROUP_TREE, to correctly solve the
problem.
All the code handling block group root is already in the upstream
kernel, thus this patch really only needs to introduce the new compat RO
flag.
This patch introduces one extra artificial limitation on block group
tree feature, that free space cache v2 and no-holes feature must be
enabled to use this new compat RO feature.
This artificial requirement is mostly to reduce the test combinations,
and can be a guideline for future features, to mostly rely on the latest
default features.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs updates from David Sterba:
"This brings some long awaited changes, the send protocol bump,
otherwise lots of small improvements and fixes. The main core part is
reworking bio handling, cleaning up the submission and endio and
improving error handling.
There are some changes outside of btrfs adding helpers or updating
API, listed at the end of the changelog.
Features:
- sysfs:
- export chunk size, in debug mode add tunable for setting its size
- show zoned among features (was only in debug mode)
- show commit stats (number, last/max/total duration)
- send protocol updated to 2
- new commands:
- ability write larger data chunks than 64K
- send raw compressed extents (uses the encoded data ioctls),
ie. no decompression on send side, no compression needed on
receive side if supported
- send 'otime' (inode creation time) among other timestamps
- send file attributes (a.k.a file flags and xflags)
- this is first version bump, backward compatibility on send and
receive side is provided
- there are still some known and wanted commands that will be
implemented in the near future, another version bump will be
needed, however we want to minimize that to avoid causing
usability issues
- print checksum type and implementation at mount time
- don't print some messages at mount (mentioned as people asked about
it), we want to print messages namely for new features so let's
make some space for that
- big metadata - this has been supported for a long time and is
not a feature that's worth mentioning
- skinny metadata - same reason, set by default by mkfs
Performance improvements:
- reduced amount of reserved metadata for delayed items
- when inserted items can be batched into one leaf
- when deleting batched directory index items
- when deleting delayed items used for deletion
- overall improved count of files/sec, decreased subvolume lock
contention
- metadata item access bounds checker micro-optimized, with a few
percent of improved runtime for metadata-heavy operations
- increase direct io limit for read to 256 sectors, improved
throughput by 3x on sample workload
Notable fixes:
- raid56
- reduce parity writes, skip sectors of stripe when there are no
data updates
- restore reading from on-disk data instead of using stripe cache,
this reduces chances to damage correct data due to RMW cycle
- refuse to replay log with unknown incompat read-only feature bit
set
- zoned
- fix page locking when COW fails in the middle of allocation
- improved tracking of active zones, ZNS drives may limit the
number and there are ENOSPC errors due to that limit and not
actual lack of space
- adjust maximum extent size for zone append so it does not cause
late ENOSPC due to underreservation
- mirror reading error messages show the mirror number
- don't fallback to buffered IO for NOWAIT direct IO writes, we don't
have the NOWAIT semantics for buffered io yet
- send, fix sending link commands for existing file paths when there
are deleted and created hardlinks for same files
- repair all mirrors for profiles with more than 1 copy (raid1c34)
- fix repair of compressed extents, unify where error detection and
repair happen
Core changes:
- bio completion cleanups
- don't double defer compression bios
- simplify endio workqueues
- add more data to btrfs_bio to avoid allocation for read requests
- rework bio error handling so it's same what block layer does,
the submission works and errors are consumed in endio
- when asynchronous bio offload fails fall back to synchronous
checksum calculation to avoid errors under writeback or memory
pressure
- new trace points
- raid56 events
- ordered extent operations
- super block log_root_transid deprecated (never used)
- mixed_backref and big_metadata sysfs feature files removed, they've
been default for sufficiently long time, there are no known users
and mixed_backref could be confused with mixed_groups
Non-btrfs changes, API updates:
- minor highmem API update to cover const arguments
- switch all kmap/kmap_atomic to kmap_local
- remove redundant flush_dcache_page()
- address_space_operations::writepage callback removed
- add bdev_max_segments() helper"
* tag 'for-5.20-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (163 commits)
btrfs: don't call btrfs_page_set_checked in finish_compressed_bio_read
btrfs: fix repair of compressed extents
btrfs: remove the start argument to check_data_csum and export
btrfs: pass a btrfs_bio to btrfs_repair_one_sector
btrfs: simplify the pending I/O counting in struct compressed_bio
btrfs: repair all known bad mirrors
btrfs: merge btrfs_dev_stat_print_on_error with its only caller
btrfs: join running log transaction when logging new name
btrfs: simplify error handling in btrfs_lookup_dentry
btrfs: send: always use the rbtree based inode ref management infrastructure
btrfs: send: fix sending link commands for existing file paths
btrfs: send: introduce recorded_ref_alloc and recorded_ref_free
btrfs: zoned: wait until zone is finished when allocation didn't progress
btrfs: zoned: write out partially allocated region
btrfs: zoned: activate necessary block group
btrfs: zoned: activate metadata block group on flush_space
btrfs: zoned: disable metadata overcommit for zoned
btrfs: zoned: introduce space_info->active_total_bytes
btrfs: zoned: finish least available block group on data bg allocation
btrfs: let can_allocate_chunk return error
...
Now that the new support is implemented, allow the ioctl to accept v2
and the compressed flag, and update the version in sysfs.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds the definitions of the new commands for send stream version 2
and their respective attributes: fallocate, FS_IOC_SETFLAGS (a.k.a.
chattr), and encoded writes. It also documents two changes to the send
stream format in v2: the receiver shouldn't assume a maximum command
size, and the DATA attribute is encoded differently to allow for writes
larger than 64k. These will be implemented in subsequent changes, and
then the ioctl will accept the new version and flag.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].
This code was transformed with the help of Coccinelle:
(linux-5.19-rc2$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)
@@
identifier S, member, array;
type T1, T2;
@@
struct S {
...
T1 member;
T2 array[
- 0
];
};
-fstrict-flex-arrays=3 is coming and we need to land these changes
to prevent issues like these in the short future:
../fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0,
but the source string has length 2 (including NUL byte) [-Wfortify-source]
strcpy(de3->name, ".");
^
Since these are all [0] to [] changes, the risk to UAPI is nearly zero. If
this breaks anything, we can use a union with a new member name.
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays
Link: https://github.com/KSPP/linux/issues/78
Build-tested-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/62b675ec.wKX6AOZ6cbE71vtF%25lkp@intel.com/
Acked-by: Dan Williams <dan.j.williams@intel.com> # For ndctl.h
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
In order to allow sending and receiving compressed data without
decompressing it, we need an interface to write pre-compressed data
directly to the filesystem and the matching interface to read compressed
data without decompressing it. This adds the definitions for ioctls to
do that and detailed explanations of how to use them.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds the initial definition of the EXTENT_TREE_V2 incompat feature
flag. This also hides the support behind CONFIG_BTRFS_DEBUG.
THIS IS A IN DEVELOPMENT FORMAT CHANGE, DO NOT USE UNLESS YOU ARE A
DEVELOPER OR A TESTER.
The format is in flux and will be added in stages, any fs will need to
be re-made between updates to the format.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is preparatory work for send protocol update to version 2 and
higher.
We have many pending protocol update requests but still don't have the
basic protocol rev in place, the first thing that must happen is to do
the actual versioning support.
The protocol version is u32 and is a new member in the send ioctl
struct. Validity of the version field is backed by a new flag bit. Old
kernels would fail when a higher version is requested. Version protocol
0 will pick the highest supported version, BTRFS_SEND_STREAM_VERSION,
that's also exported in sysfs.
The version is still unchanged and will be increased once we have new
incompatible commands or stream updates.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add support for fsverity in btrfs. To support the generic interface in
fs/verity, we add two new item types in the fs tree for inodes with
verity enabled. One stores the per-file verity descriptor and btrfs
verity item and the other stores the Merkle tree data itself.
Verity checking is done in end_page_read just before a page is marked
uptodate. This naturally handles a variety of edge cases like holes,
preallocated extents, and inline extents. Some care needs to be taken to
not try to verity pages past the end of the file, which are accessed by
the generic buffered file reading code under some circumstances like
reading to the end of the last page and trying to read again. Direct IO
on a verity file falls back to buffered reads.
Verity relies on PageChecked for the Merkle tree data itself to avoid
re-walking up shared paths in the tree. For this reason, we need to
cache the Merkle tree data. Since the file is immutable after verity is
turned on, we can cache it at an index past EOF.
Use the new inode ro_flags to store verity on the inode item, so that we
can enable verity on a file, then rollback to an older kernel and still
mount the file system and read the file. Since we can't safely write the
file anymore without ruining the invariants of the Merkle tree, we mark
a ro_compat flag on the file system when a file has verity enabled.
Acked-by: Eric Biggers <ebiggers@google.com>
Co-developed-by: Chris Mason <clm@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch introduces the ZONED incompat flag. The flag indicates that
the volume management will satisfy the constraints imposed by
host-managed zoned block devices (aligned chunk allocation, append-only
updates, reset zone after filled).
As the zoned support will happen incrementally due to enhancing some
core infrastructure like super block writes, tree-log, raid support, the
feature will appear in sysfs only on debug builds. It will be enabled
once the support is feature complete and applications can reliably check
whether zoned support is present or not.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add retrieval of the filesystem's metadata UUID to the fsinfo ioctl.
This is driven by setting the BTRFS_FS_INFO_FLAG_METADATA_UUID flag in
btrfs_ioctl_fs_info_args::flags.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add retrieval of the filesystem's generation to the fsinfo ioctl. This is
driven by setting the BTRFS_FS_INFO_FLAG_GENERATION flag in
btrfs_ioctl_fs_info_args::flags.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With the recent addition of filesystem checksum types other than CRC32c,
it is not anymore hard-coded which checksum type a btrfs filesystem uses.
Up to now there is no good way to read the filesystem checksum, apart from
reading the filesystem UUID and then query sysfs for the checksum type.
Add a new csum_type and csum_size fields to the BTRFS_IOC_FS_INFO ioctl
command which usually is used to query filesystem features. Also add a
flags member indicating that the kernel responded with a set csum_type and
csum_size field.
For compatibility reasons, only return the csum_type and csum_size if
the BTRFS_FS_INFO_FLAG_CSUM_INFO flag was passed to the kernel. Also
clear any unknown flags so we don't pass false positives to user-space
newer than the kernel.
To simplify further additions to the ioctl, also switch the padding to a
u8 array. Pahole was used to verify the result of this switch:
The csum members are added before flags, which might look odd, but this
is to keep the alignment requirements and not to introduce holes in the
structure.
$ pahole -C btrfs_ioctl_fs_info_args fs/btrfs/btrfs.ko
struct btrfs_ioctl_fs_info_args {
__u64 max_id; /* 0 8 */
__u64 num_devices; /* 8 8 */
__u8 fsid[16]; /* 16 16 */
__u32 nodesize; /* 32 4 */
__u32 sectorsize; /* 36 4 */
__u32 clone_alignment; /* 40 4 */
__u16 csum_type; /* 44 2 */
__u16 csum_size; /* 46 2 */
__u64 flags; /* 48 8 */
__u8 reserved[968]; /* 56 968 */
/* size: 1024, cachelines: 16, members: 10 */
};
Fixes: 3951e7f050 ("btrfs: add xxhash64 to checksumming algorithms")
Fixes: 3831bf0094 ("btrfs: add sha256 to checksumming algorithm")
CC: stable@vger.kernel.org # 5.5+
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The commit 9c1036fdb1 ("btrfs: Remove BTRFS_SUBVOL_CREATE_ASYNC
support") breaks strace build with the kernel headers from git:
btrfs.c: In function "btrfs_test_subvol_ioctls":
btrfs.c:531:23: error: "BTRFS_SUBVOL_CREATE_ASYNC" undeclared (first use
in this function)
vol_args_v2.flags = BTRFS_SUBVOL_CREATE_ASYNC;
Moreover, it is improper to break UAPI, strace uses the definitions to
decode ioctls that are considered part of public API.
Restore the macro definition and put it under "#ifndef __KERNEL__"
in order to prevent inadvertent in-kernel usage.
Fixes: 9c1036fdb1 ("btrfs: Remove BTRFS_SUBVOL_CREATE_ASYNC support")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This functionality was deprecated in kernel 5.4. Since no one has
complained of the impending removal it's time we did so.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
This ioctl will be responsible for deleting a subvolume using its id.
This can be used when a system has a file system mounted from a
subvolume, rather than the root file system, like below:
/
@subvol1/
@subvol2/
@subvol_default/
If only @subvol_default is mounted, we have no path to reach @subvol1
and @subvol2, thus no way to delete them. Current subvolume delete ioctl
takes a file handle point as argument, and if @subvol_default is
mounted, we can't reach @subvol1 and @subvol2 from the same mount point.
This patch introduces a new ioctl BTRFS_IOC_SNAP_DESTROY_V2 that takes
the extended structure with flags to allow to delete subvolume using
subvolid.
Now, we can use this new ioctl specifying the subvolume id and refer to
the same mount point. It doesn't matter which subvolume was mounted,
since we can reach to the desired one using the subvolume id, and then
delete it.
The full path to the subvolume id is resolved internally and access is
verified as if the subvolume was accessed by path.
The volume args v2 structure is extended to use the existing union for
subvolume id specification, that's valid in case the
BTRFS_SUBVOL_SPEC_BY_ID is set.
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
The ioctl data for devices or subvolumes can be passed via
btrfs_ioctl_vol_args or btrfs_ioctl_vol_args_v2. The latter is more
versatile and needs some caution as some of the flags make sense only
for some ioctls.
As we're going to extend the flags, define support masks for each ioctl
class separately.
Reviewed-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The new raid1c3 and raid1c4 profiles are backward incompatible and the
name shall be 'raid1c34', the status can be found in the global
supported features in /sys/fs/btrfs/features or in the per-filesystem
directory.
Signed-off-by: David Sterba <dsterba@suse.com>
Add new block group profile to store 4 copies in a simliar way that
current RAID1 does. The profile attributes and constraints are defined
in the raid table and used by the same code that already handles the 2-
and 3-copy RAID1.
The minimum number of devices is 4, the maximum number of devices/chunks
that can be lost/damaged is 3. There is no comparable traditional RAID
level, the profile is added for future needs to accompany triple-parity
and beyond.
Signed-off-by: David Sterba <dsterba@suse.com>
Add new block group profile to store 3 copies in a simliar way that
current RAID1 does. The profile attributes and constraints are defined
in the raid table and used by the same code that already handles the
2-copy RAID1.
The minimum number of devices is 3, the maximum number of devices/chunks
that can be lost/damaged is 2. Like RAID6 but with 33% space
utilization.
Signed-off-by: David Sterba <dsterba@suse.com>
In commit c11d2c236c ("Btrfs: add ioctl to get and reset the device
stats") the get_dev_stats ioctl was added.
Shortly thereafter, in commit b27f7c0c15 ("btrfs: join DEV_STATS
ioctls to one") , the flags field was added. However, the calculation
for unused padding space was not updated, which also invalidated the
comment.
Clarify what happened to reduce confusion and wasted time for anyone
implementing this.
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
I lifted the btrfs label get/set ioctls to the vfs some time ago, but
never followed up to use those common definitions directly in btrfs.
This patch does that.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Support for a new command that can be used eg. as a command
$ btrfs device scan --forget [dev]'
(the final name may change though)
to undo the effects of 'btrfs device scan [dev]'. For this purpose
this patch proposes to use ioctl #5 as it was empty and is next to the
SCAN ioctl.
The new ioctl BTRFS_IOC_FORGET_DEV works only on the control device
(/dev/btrfs-control) to unregister one or all devices, devices that are
not mounted.
The argument is struct btrfs_ioctl_vol_args, ::name specifies the device
path. To unregister all device, the path is an empty string.
Again, the devices are removed only if they aren't part of a mounte
filesystem.
This new ioctl provides:
- release of unwanted btrfs_fs_devices and btrfs_devices structures
from memory if the device is not going to be mounted
- ability to mount filesystem in degraded mode, when one devices is
corrupted like in split brain raid1
- running test cases which would require reloading the kernel module
but this is not possible eg. due to mounted filesystem or built-in
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
This field is going to be used when the user wants to change the UUID
of the filesystem without having to rewrite all metadata blocks. This
field adds another level of indirection such that when the FSID is
changed what really happens is the current UUID (the one with which the
fs was created) is copied to the 'metadata_uuid' field in the superblock
as well as a new incompat flag is set METADATA_UUID. When the kernel
detects this flag is set it knows that the superblock in fact has 2
UUIDs:
1. Is the UUID which is user-visible, currently known as FSID.
2. Metadata UUID - this is the UUID which is stamped into all on-disk
datastructures belonging to this file system.
When the new incompat flag is present device scanning checks whether
both fsid/metadata_uuid of the scanned device match any of the
registered filesystems. When the flag is not set then both UUIDs are
equal and only the FSID is retained on disk, metadata_uuid is set only
in-memory during mount.
Additionally a new metadata_uuid field is also added to the fs_info
struct. It's initialised either with the FSID in case METADATA_UUID
incompat flag is not set or with the metdata_uuid of the superblock
otherwise.
This commit introduces the new fields as well as the new incompat flag
and switches all users of the fsid to the new logic.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor updates in comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
