pm24.git/fs/btrfs/dev-replace.c, branch v5.6

Merge tag 'for-5.6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2020-01-28T22:53:31Z

Pull btrfs updates from David Sterba: "Features, highlights: - async discard - "mount -o discard=async" to enable it - freed extents are not discarded immediatelly, but grouped together and trimmed later, with IO rate limiting - the "sync" mode submits short extents that could have been ignored completely by the device, for SATA prior to 3.1 the requests are unqueued and have a big impact on performance - the actual discard IO requests have been moved out of transaction commit to a worker thread, improving commit latency - IO rate and request size can be tuned by sysfs files, for now enabled only with CONFIG_BTRFS_DEBUG as we might need to add/delete the files and don't have a stable-ish ABI for general use, defaults are conservative - export device state info in sysfs, eg. missing, writeable - no discard of extents known to be untouched on disk (eg. after reservation) - device stats reset is logged with process name and PID that called the ioctl Fixes: - fix missing hole after hole punching and fsync when using NO_HOLES - writeback: range cyclic mode could miss some dirty pages and lead to OOM - two more corner cases for metadata_uuid change after power loss during the change - fix infinite loop during fsync after mix of rename operations Core changes: - qgroup assign returns ENOTCONN when quotas not enabled, used to return EINVAL that was confusing - device closing does not need to allocate memory anymore - snapshot aware code got removed, disabled for years due to performance problems, reimplmentation will allow to select wheter defrag breaks or does not break COW on shared extents - tree-checker: - check leaf chunk item size, cross check against number of stripes - verify location keys for DIR_ITEM, DIR_INDEX and XATTR items - new self test for physical -> logical mapping code, used for super block range exclusion - assertion helpers/macros updated to avoid objtool "unreachable code" reports on older compilers or config option combinations" * tag 'for-5.6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (84 commits) btrfs: free block groups after free'ing fs trees btrfs: Fix split-brain handling when changing FSID to metadata uuid btrfs: Handle another split brain scenario with metadata uuid feature btrfs: Factor out metadata_uuid code from find_fsid. btrfs: Call find_fsid from find_fsid_inprogress Btrfs: fix infinite loop during fsync after rename operations btrfs: set trans->drity in btrfs_commit_transaction btrfs: drop log root for dropped roots btrfs: sysfs, add devid/dev_state kobject and device attributes btrfs: Refactor btrfs_rmap_block to improve readability btrfs: Add self-tests for btrfs_rmap_block btrfs: selftests: Add support for dummy devices btrfs: Move and unexport btrfs_rmap_block btrfs: separate definition of assertion failure handlers btrfs: device stats, log when stats are zeroed btrfs: fix improper setting of scanned for range cyclic write cache pages btrfs: safely advance counter when looking up bio csums btrfs: remove unused member btrfs_device::work btrfs: remove unnecessary wrapper get_alloc_profile btrfs: add correction to handle -1 edge case in async discard ...

btrfs: dev-replace: remove warning for unknown return codes when finished

2020-01-25T11:49:12Z

The fstests btrfs/011 triggered a warning at the end of device replace, [ 1891.998975] BTRFS warning (device vdd): failed setting block group ro: -28 [ 1892.038338] BTRFS error (device vdd): btrfs_scrub_dev(/dev/vdd, 1, /dev/vdb) failed -28 [ 1892.059993] ------------[ cut here ]------------ [ 1892.063032] WARNING: CPU: 2 PID: 2244 at fs/btrfs/dev-replace.c:506 btrfs_dev_replace_start.cold+0xf9/0x140 [btrfs] [ 1892.074346] CPU: 2 PID: 2244 Comm: btrfs Not tainted 5.5.0-rc7-default+ #942 [ 1892.079956] RIP: 0010:btrfs_dev_replace_start.cold+0xf9/0x140 [btrfs] [ 1892.096576] RSP: 0018:ffffbb58c7b3fd10 EFLAGS: 00010286 [ 1892.098311] RAX: 00000000ffffffe4 RBX: 0000000000000001 RCX: 8888888888888889 [ 1892.100342] RDX: 0000000000000001 RSI: ffff9e889645f5d8 RDI: ffffffff92821080 [ 1892.102291] RBP: ffff9e889645c000 R08: 000001b8878fe1f6 R09: 0000000000000000 [ 1892.104239] R10: ffffbb58c7b3fd08 R11: 0000000000000000 R12: ffff9e88a0017000 [ 1892.106434] R13: ffff9e889645f608 R14: ffff9e88794e1000 R15: ffff9e88a07b5200 [ 1892.108642] FS: 00007fcaed3f18c0(0000) GS:ffff9e88bda00000(0000) knlGS:0000000000000000 [ 1892.111558] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1892.113492] CR2: 00007f52509ff420 CR3: 00000000603dd002 CR4: 0000000000160ee0 [ 1892.115814] Call Trace: [ 1892.116896] btrfs_dev_replace_by_ioctl+0x35/0x60 [btrfs] [ 1892.118962] btrfs_ioctl+0x1d62/0x2550 [btrfs] caused by the previous patch ("btrfs: scrub: Require mandatory block group RO for dev-replace"). Hitting ENOSPC is possible and could happen when the block group is set read-only, preventing NOCOW writes to the area that's being accessed by dev-replace. This has happend with scratch devices of size 12G but not with 5G and 20G, so this is depends on timing and other activity on the filesystem. The whole replace operation is restartable, the space state should be examined by the user in any case. The error code is propagated back to the ioctl caller so the kernel warning is causing false alerts. Signed-off-by: David Sterba

btrfs: sysfs, add devid/dev_state kobject and device attributes

2020-01-23T16:24:36Z

New sysfs attributes that track the filesystem status of devices, stored in the per-filesystem directory in /sys/fs/btrfs/FSID/devinfo . There's a directory for each device, with name corresponding to the numerical device id. in_fs_metadata - device is in the list of fs metadata missing - device is missing (no device node or block device) replace_target - device is target of replace writeable - writes from fs are allowed These attributes reflect the state of the device::dev_state and created at mount time. Sample output: $ pwd /sys/fs/btrfs/6e1961f1-5918-4ecc-a22f-948897b409f7/devinfo/1/ $ ls in_fs_metadata missing replace_target writeable $ cat missing 0 The output from these attributes are 0 or 1. 0 indicates unset and 1 indicates set. These attributes are readonly. It is observed that the device delete thread and sysfs read thread will not race because the delete thread calls sysfs kobject_put() which in turn waits for existing sysfs read to complete. Note for device replace devid swap: During the replace the target device temporarily assumes devid 0 before assigning the devid of the soruce device. In btrfs_dev_replace_finishing() we remove source sysfs devid using the function btrfs_sysfs_remove_devices_attr(), so after that call kobject_rename() to update the devid in the sysfs. This adds and calls btrfs_sysfs_update_devid() helper function to update the device id. Signed-off-by: Anand Jain Reviewed-by: David Sterba [ update changelog ] Signed-off-by: David Sterba

btrfs: add __pure attribute to functions

2019-11-18T11:46:52Z

The attribute is more relaxed than const and the functions could dereference pointers, as long as the observable state is not changed. We do have such functions, based on -Wsuggest-attribute=pure . The visible effects of this patch are negligible, there are differences in the assembly but hard to summarize. Reviewed-by: Nikolay Borisov Signed-off-by: David Sterba

btrfs: move cond_wake_up functions out of ctree

2019-09-09T12:59:15Z

The file ctree.h serves as a header for everything and has become quite bloated. Split some helpers that are generic and create a new file that should be the catch-all for code that's not btrfs-specific. Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba

btrfs: replace: BTRFS_DEV_REPLACE_ITEM_STATE_x defines should go

2019-09-09T12:59:11Z

The BTRFS_DEV_REPLACE_ITEM_STATE_x defines, as shown in [1], are unused in both kernel and btrfs-progs (except for one instance of BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED in kernel). [1] btrfs.h:#define BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED 2 btrfs.h:#define BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED 3 btrfs.h:#define BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED 4 Further these define-values are different form its counterpart BTRFS_IOCTL_DEV_REPLACE_STATE_x series as shown in [2]. [2] btrfs_tree.h:#define BTRFS_DEV_REPLACE_ITEM_STATE_SUSPENDED 2 btrfs_tree.h:#define BTRFS_DEV_REPLACE_ITEM_STATE_FINISHED 3 btrfs_tree.h:#define BTRFS_DEV_REPLACE_ITEM_STATE_CANCELED 4 So this patch deletes the BTRFS_DEV_REPLACE_ITEM_STATE_x altogether, and one instance of BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED is replaced with BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED in the kernel. Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: remove mapping tree structures indirection

2019-07-01T11:34:56Z

fs_info::mapping_tree is the physical<->logical mapping tree and uses the same underlying structure as extents, but is embedded to another structure. There are no other members and this indirection is useless. No functional change. Signed-off-by: David Sterba

btrfs: Remove redundant assignment of tgt_device->commit_total_bytes

2019-07-01T11:34:55Z

This is already done in btrfs_init_dev_replace_tgtdev which is the first phase of device replace, called before doing scrub. During that time exclusive lock is held. Additionally btrfs_fs_device::commit_total_bytes is always set based on the size of the underlying block device which shouldn't change once set. This makes the 2nd assignment of the variable in the finishing phase redundant. Reviewed-by: Johannes Thumshirn Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: Explicitly reserve space for devreplace item

2019-07-01T11:34:54Z

Part of device replace involves writing an item to the device root containing information about pending replace operations. Currently space for this item is not being explicitly reserved so this works thanks to presence of global reserve. While not fatal it's not a good practice. Let's be explicit about space requirement of device replace and reserve space when starting the transaction. Reviewed-by: Johannes Thumshirn Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: Streamline replace sem unlock in btrfs_dev_replace_start

2019-07-01T11:34:54Z

There are only 2 branches which goto leave label with need_unlock set to true. Essentially need_unlock is used as a substitute for directly calling up_write. Since the branches needing this are only 2 and their context is not that big it's more clear to just call up_write where required. No functional changes. Reviewed-by: Johannes Thumshirn Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba