linux-dev/fs/fscache, branch master

fscache: add tracepoint when failing cookie

2022-08-09T13:13:59Z

Signed-off-by: Jeff Layton Signed-off-by: David Howells

fscache: don't leak cookie access refs if invalidation is in progress or failed

2022-08-09T13:13:55Z

It's possible for a request to invalidate a fscache_cookie will come in while we're already processing an invalidation. If that happens we currently take an extra access reference that will leak. Only call __fscache_begin_cookie_access if the FSCACHE_COOKIE_DO_INVALIDATE bit was previously clear. Also, ensure that we attempt to clear the bit when the cookie is "FAILED" and put the reference to avoid an access leak. Fixes: 85e4ea1049c7 ("fscache: Fix invalidation/lookup race") Suggested-by: David Howells Signed-off-by: Jeff Layton Signed-off-by: David Howells

fscache: Fix invalidation/lookup race

2022-07-05T15:12:55Z

If an NFS file is opened for writing and closed, fscache_invalidate() will be asked to invalidate the file - however, if the cookie is in the LOOKING_UP state (or the CREATING state), then request to invalidate doesn't get recorded for fscache_cookie_state_machine() to do something with. Fix this by making __fscache_invalidate() set a flag if it sees the cookie is in the LOOKING_UP state to indicate that we need to go to invalidation. Note that this requires a count on the n_accesses counter for the state machine, which that will release when it's done. fscache_cookie_state_machine() then shifts to the INVALIDATING state if it sees the flag. Without this, an nfs file can get corrupted if it gets modified locally and then read locally as the cache contents may not get updated. Fixes: d24af13e2e23 ("fscache: Implement cookie invalidation") Reported-by: Max Kellermann Signed-off-by: David Howells Tested-by: Max Kellermann Link: https://lore.kernel.org/r/YlWWbpW5Foynjllo@rabbit.intern.cm-ag [1]

fscache: Introduce fscache_cookie_is_dropped()

2022-07-05T15:12:20Z

FSCACHE_COOKIE_STATE_DROPPED will be read more than once, so let's add a helper to avoid code duplication. Signed-off-by: Yue Hu Signed-off-by: David Howells Link: https://listman.redhat.com/archives/linux-cachefs/2022-May/006919.html

fscache: Fix if condition in fscache_wait_on_volume_collision()

2022-07-05T15:12:20Z

After waiting for the volume to complete the acquisition with timeout, the if condition under which potential volume collision occurs should be acquire the volume is still pending rather than not pending so that we will continue to wait until the pending flag is cleared. Also, use the existing test pending wrapper directly instead of test_bit(). Fixes: 62ab63352350 ("fscache: Implement volume registration") Signed-off-by: Yue Hu Signed-off-by: David Howells Reviewed-by: Gao Xiang Reviewed-by: Jeffle Xu Reviewed-by: Jeff Layton Link: https://listman.redhat.com/archives/linux-cachefs/2022-May/006918.html

fscache: remove FSCACHE_OLD_API Kconfig option

2022-04-08T22:54:37Z

Commit 01491a756578 ("fscache, cachefiles: Disable configuration") added the FSCACHE_OLD_API configuration when rewritten. Now, it's not used any more. Remove it. Signed-off-by: Yue Hu Signed-off-by: David Howells cc: linux-cachefs@redhat.com Link: https://listman.redhat.com/archives/linux-cachefs/2022-March/006647.html # v1

fscache: Use wrapper fscache_set_cache_state() directly when relinquishing

2022-04-08T22:54:37Z

We already have the wrapper function to set cache state. Signed-off-by: Yue Hu Signed-off-by: David Howells Reviewed-by: Jeffle Xu cc: linux-cachefs@redhat.com Link: https://listman.redhat.com/archives/linux-cachefs/2022-April/006648.html # v1

fscache: Move fscache_cookies_seq_ops specific code under CONFIG_PROC_FS

2022-04-08T22:54:37Z

fscache_cookies_seq_ops is only used in proc.c that is compiled under enabled CONFIG_PROC_FS, so move related code under this config. The same case exsits in internal.h. Also, make fscache_lru_cookie_timeout static due to no user outside of cookie.c. Signed-off-by: Yue Hu Signed-off-by: David Howells cc: linux-cachefs@redhat.com Link: https://listman.redhat.com/archives/linux-cachefs/2022-April/006649.html # v1

fscache: Remove the cookie parameter from fscache_clear_page_bits()

2022-04-08T22:54:37Z

The cookie is not used at all, remove it and update the usage in io.c and afs/write.c (which is the only user outside of fscache currently) at the same time. [DH: Amended the documentation also] Signed-off-by: Yue Hu Signed-off-by: David Howells cc: linux-cachefs@redhat.com Link: https://listman.redhat.com/archives/linux-cachefs/2022-April/006659.html

Merge tag 'netfs-prep-20220318' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

2022-03-31T22:49:36Z

Pull netfs updates from David Howells: "Netfs prep for write helpers. Having had a go at implementing write helpers and content encryption support in netfslib, it seems that the netfs_read_{,sub}request structs and the equivalent write request structs were almost the same and so should be merged, thereby requiring only one set of alloc/get/put functions and a common set of tracepoints. Merging the structs also has the advantage that if a bounce buffer is added to the request struct, a read operation can be performed to fill the bounce buffer, the contents of the buffer can be modified and then a write operation can be performed on it to send the data wherever it needs to go using the same request structure all the way through. The I/O handlers would then transparently perform any required crypto. This should make it easier to perform RMW cycles if needed. The potentially common functions and structs, however, by their names all proclaim themselves to be associated with the read side of things. The bulk of these changes alter this in the following ways: - Rename struct netfs_read_{,sub}request to netfs_io_{,sub}request. - Rename some enums, members and flags to make them more appropriate. - Adjust some comments to match. - Drop "read"/"rreq" from the names of common functions. For instance, netfs_get_read_request() becomes netfs_get_request(). - The ->init_rreq() and ->issue_op() methods become ->init_request() and ->issue_read(). I've kept the latter as a read-specific function and in another branch added an ->issue_write() method. The driver source is then reorganised into a number of files: fs/netfs/buffered_read.c Create read reqs to the pagecache fs/netfs/io.c Dispatchers for read and write reqs fs/netfs/main.c Some general miscellaneous bits fs/netfs/objects.c Alloc, get and put functions fs/netfs/stats.c Optional procfs statistics. and future development can be fitted into this scheme, e.g.: fs/netfs/buffered_write.c Modify the pagecache fs/netfs/buffered_flush.c Writeback from the pagecache fs/netfs/direct_read.c DIO read support fs/netfs/direct_write.c DIO write support fs/netfs/unbuffered_write.c Write modifications directly back Beyond the above changes, there are also some changes that affect how things work: - Make fscache_end_operation() generally available. - In the netfs tracing header, generate enums from the symbol -> string mapping tables rather than manually coding them. - Add a struct for filesystems that uses netfslib to put into their inode wrapper structs to hold extra state that netfslib is interested in, such as the fscache cookie. This allows netfslib functions to be set in filesystem operation tables and jumped to directly without having to have a filesystem wrapper. - Add a member to the struct added above to track the remote inode length as that may differ if local modifications are buffered. We may need to supply an appropriate EOF pointer when storing data (in AFS for example). - Pass extra information to netfs_alloc_request() so that the ->init_request() hook can access it and retain information to indicate the origin of the operation. - Make the ->init_request() hook return an error, thereby allowing a filesystem that isn't allowed to cache an inode (ceph or cifs, for example) to skip readahead. - Switch to using refcount_t for subrequests and add tracepoints to log refcount changes for the request and subrequest structs. - Add a function to consolidate dispatching a read request. Similar code is used in three places and another couple are likely to be added in the future" Link: https://lore.kernel.org/all/2639515.1648483225@warthog.procyon.org.uk/ * tag 'netfs-prep-20220318' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: afs: Maintain netfs_i_context::remote_i_size netfs: Keep track of the actual remote file size netfs: Split some core bits out into their own file netfs: Split fs/netfs/read_helper.c netfs: Rename read_helper.c to io.c netfs: Prepare to split read_helper.c netfs: Add a function to consolidate beginning a read netfs: Add a netfs inode context ceph: Make ceph_init_request() check caps on readahead netfs: Change ->init_request() to return an error code netfs: Refactor arguments for netfs_alloc_read_request netfs: Adjust the netfs_failure tracepoint to indicate non-subreq lines netfs: Trace refcounting on the netfs_io_subrequest struct netfs: Trace refcounting on the netfs_io_request struct netfs: Adjust the netfs_rreq tracepoint slightly netfs: Split netfs_io_* object handling out netfs: Finish off rename of netfs_read_request to netfs_io_request netfs: Rename netfs_read_*request to netfs_io_*request netfs: Generate enums from trace symbol mapping lists fscache: export fscache_end_operation()