kernel/git/stable/linux.git/fs/btrfs/sysfs.c, branch linux-5.18.y

btrfs: make the bg_reclaim_threshold per-space info

2022-08-17T12:42:26+00:00

[ Upstream commit bb5a098d9791f184899499531ff4411089e2a5e0 ] For non-zoned file systems it's useful to have the auto reclaim feature, however there are different use cases for non-zoned, for example we may not want to reclaim metadata chunks ever, only data chunks. Move this sysfs flag to per-space_info. This won't affect current users because this tunable only ever did anything for zoned, and that is currently hidden behind BTRFS_CONFIG_DEBUG. Tested-by: Pankaj Raghav Signed-off-by: Josef Bacik [ jth restore global bg_reclaim_threshold ] Signed-off-by: Johannes Thumshirn Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin

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

2022-05-05T19:05:56+00:00

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

btrfs: replace BUILD_BUG_ON by static_assert

2022-03-14T12:13:49+00:00

The static_assert introduced in 6bab69c65013 ("build_bug.h: add wrapper for _Static_assert") has been supported by compilers for a long time (gcc 4.6, clang 3.0) and can be used in header files. We don't need to put BUILD_BUG_ON to random functions but rather keep it next to the definition. The exception here is the UAPI header btrfs_tree.h that could be potentially included by userspace code and the static assert is not defined (nor used in any other header). Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba

btrfs: add definition for EXTENT_TREE_V2

2022-03-14T12:13:48+00:00

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 Signed-off-by: David Sterba

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