kernel/git/stable/linux.git/fs/btrfs/sysfs.c, branch linux-5.17.y

btrfs: sysfs: export the balance paused state of exclusive operation

2022-05-12T10:32:20+00:00

commit 3e1ad196385c65c1454aceab1226d9a4baca27d5 upstream. The new state allowing device addition with paused balance is not exported to user space so it can't recognize it and actually start the operation. Fixes: efc0e69c2fea ("btrfs: introduce exclusive operation BALANCE_PAUSED state") CC: stable@vger.kernel.org # 5.17 Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

btrfs: sysfs: add devinfo/fsid to retrieve actual fsid from the device

2022-01-07T13:18:25+00:00

In the case of the seed device, the fsid can be different from the mounted sprout fsid. The userland has to read the device superblock to know the fsid but, that idea fails if the device is missing. So add a sysfs interface devinfo//fsid to show the fsid of the device. For example: $ cd /sys/fs/btrfs/b10b02a5-f9de-4276-b9e8-2bfd09a578a8 $ cat devinfo/1/fsid c44d771f-639d-4df3-99ec-5bc7ad2af93b $ cat devinfo/3/fsid b10b02a5-f9de-4276-b9e8-2bfd09a578a8 Though it's related to seeding, the name of the sysfs file is plain fsid as it matches what blkid says. A path to the device's fsid will aid scripting. Reviewed-by: Josef Bacik Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: sysfs: convert scnprintf and snprintf to sysfs_emit

2021-10-26T17:08:07+00:00

Commit 2efc459d06f1 ("sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs out") merged in 5.10 introduced two new functions sysfs_emit() and sysfs_emit_at() which are aware of the PAGE_SIZE limit of the output buffer. Use the above two new functions instead of scnprintf() and snprintf() in various sysfs show(). Reviewed-by: Josef Bacik Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: sysfs: document structures and their associated files

2021-08-23T11:19:12+00:00

Sysfs file has grown big. It takes some time to locate the correct struct attribute to add new files. Create a table and map the struct attribute to its sysfs path. Also, fix the comment about the debug sysfs path. And add the comments to the attributes instead of attribute group, where sysfs file names are defined. Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: zoned: allow disabling of zone auto reclaim

2021-08-23T11:19:11+00:00

Automatically reclaiming dirty zones might not always be desired for all workloads, especially as there are currently still some rough edges with the relocation code on zoned filesystems. Allow disabling zone auto reclaim on a per filesystem basis by writing 0 as the threshold value. Reviewed-by: Naohiro Aota Signed-off-by: Johannes Thumshirn Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: initial fsverity support

2021-08-23T11:19:09+00:00

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 Co-developed-by: Chris Mason Signed-off-by: Chris Mason Signed-off-by: Boris Burkov Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: allow read-write for 4K sectorsize on 64K page size systems

2021-08-23T11:19:06+00:00

Since now we support data and metadata read-write for subpage, remove the RO requirement for subpage mount. There are some extra limitations though: - For now, subpage RW mount is still considered experimental Thus that mount warning will still be there. - No compression support There are still quite some PAGE_SIZE hard coded and quite some call sites use extent_clear_unlock_delalloc() to unlock locked_page. This will screw up subpage helpers. Now for subpage RW mount, no matter what mount option or inode attr is set, all writes will not be compressed. Although reading compressed data has no problem. - No defrag for subpage case The defrag support for subpage case will come in later patches, which will also rework the defrag workflow. - No inline extent will be created This is mostly due to the fact that filemap_fdatawrite_range() will trigger more write than the range specified. In fallocate calls, this behavior can make us to writeback which can be inlined, before we enlarge the i_size. This is a very special corner case, and even current btrfs check won't report error on such inline extent + regular extent. But considering how much effort has been put to prevent such inline + regular, I'd prefer to cut off inline extent completely until we have a good solution. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba

btrfs: rip out btrfs_space_info::total_bytes_pinned

2021-06-22T12:55:25+00:00

We used this in may_commit_transaction() in order to determine if we needed to commit the transaction. However we no longer have that logic and thus have no use of this counter anymore, so delete it. Reviewed-by: Nikolay Borisov Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: sysfs: export dev stats in devinfo directory

2021-06-22T12:11:57+00:00

The device stats can be read by ioctl, wrapped by command 'btrfs device stats'. Provide another source where to read the information in /sys/fs/btrfs/FSID/devinfo/DEVID/error_stats . The format is a list of 'key value' pairs one per line, which is common in other stat files. The names are the same as used in other device stat outputs. The stats are all in one file as it's the snapshot of all available stats. The 'one value per file' format is not very suitable here. The stats should be valid right after the stats item is read from disk, shortly after initializing the device. In case the stats are not yet valid, print just 'invalid' as the file contents. Reviewed-by: Anand Jain Signed-off-by: David Sterba

btrfs: sysfs: fix format string for some discard stats

2021-06-21T13:19:06+00:00

The type of discard_bitmap_bytes and discard_extent_bytes is u64 so the format should be %llu, though the actual values would hardly ever overflow to negative values. Reviewed-by: Qu Wenruo Reviewed-by: Anand Jain Signed-off-by: David Sterba