kernel/include/trace/events/afs.h, branch linux-5.1.y

afs: Fix race in async call refcounting

2019-01-17T15:17:28Z

There's a race between afs_make_call() and afs_wake_up_async_call() in the case that an error is returned from rxrpc_kernel_send_data() after it has queued the final packet. afs_make_call() will try and clean up the mess, but the call state may have been moved on thereby causing afs_process_async_call() to also try and to delete the call. Fix this by: (1) Getting an extra ref for an asynchronous call for the call itself to hold. This makes sure the call doesn't evaporate on us accidentally and will allow the call to be retained by the caller in a future patch. The ref is released on leaving afs_make_call() or afs_wait_for_call_to_complete(). (2) In the event of an error from rxrpc_kernel_send_data(): (a) Don't set the call state to AFS_CALL_COMPLETE until *after* the call has been aborted and ended. This prevents afs_deliver_to_call() from doing anything with any notifications it gets. (b) Explicitly end the call immediately to prevent further callbacks. (c) Cancel any queued async_work and wait for the work if it's executing. This allows us to be sure the race won't recur when we change the state. We put the work queue's ref on the call if we managed to cancel it. (d) Put the call's ref that we got in (1). This belongs to us as long as the call is in state AFS_CALL_CL_REQUESTING. Fixes: 341f741f04be ("afs: Refcount the afs_call struct") Signed-off-by: David Howells

afs: Probe multiple fileservers simultaneously

2018-10-23T23:41:09Z

Send probes to all the unprobed fileservers in a fileserver list on all addresses simultaneously in an attempt to find out the fastest route whilst not getting stuck for 20s on any server or address that we don't get a reply from. This alleviates the problem whereby attempting to access a new server can take a long time because the rotation algorithm ends up rotating through all servers and addresses until it finds one that responds. Signed-off-by: David Howells

afs: Implement YFS support in the fs client

2018-10-23T23:41:08Z

Implement support for talking to YFS-variant fileservers in the cache manager and the filesystem client. These implement upgraded services on the same port as their AFS services. YFS fileservers provide expanded capabilities over AFS. Signed-off-by: David Howells

afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS

2018-10-23T23:41:08Z

Increase the sizes of the volume ID to 64 bits and the vnode ID (inode number equivalent) to 96 bits to allow the support of YFS. This requires the iget comparator to check the vnode->fid rather than i_ino and i_generation as i_ino is not sufficiently capacious. It also requires this data to be placed into the vnode cache key for fscache. For the moment, just discard the top 32 bits of the vnode ID when returning it though stat. Signed-off-by: David Howells

afs: Add a couple of tracepoints to log I/O errors

2018-10-23T23:41:07Z

Add a couple of tracepoints to log the production of I/O errors within the AFS filesystem. Signed-off-by: David Howells

afs: Set up the iov_iter before calling afs_extract_data()

2018-10-23T23:41:07Z

afs_extract_data sets up a temporary iov_iter and passes it to AF_RXRPC each time it is called to describe the remaining buffer to be filled. Instead: (1) Put an iterator in the afs_call struct. (2) Set the iterator for each marshalling stage to load data into the appropriate places. A number of convenience functions are provided to this end (eg. afs_extract_to_buf()). This iterator is then passed to afs_extract_data(). (3) Use the new ITER_DISCARD iterator to discard any excess data provided by FetchData. Signed-off-by: David Howells

afs: Better tracing of protocol errors

2018-10-23T23:41:07Z

Include the site of detection of AFS protocol errors in trace lines to better be able to determine what went wrong. Signed-off-by: David Howells

afs: Add a tracepoint to record callbacks from unlisted servers

2018-05-14T14:15:18Z

Add a tracepoint to record callbacks from servers for which we don't have a record. Signed-off-by: David Howells

afs: Trace protocol errors

2018-04-09T20:54:48Z

Trace protocol errors detected in afs. Signed-off-by: David Howells

afs: Locally edit directory data for mkdir/create/unlink/...

2018-04-09T20:54:48Z

Locally edit the contents of an AFS directory upon a successful inode operation that modifies that directory (such as mkdir, create and unlink) so that we can avoid the current practice of re-downloading the directory after each change. This is viable provided that the directory version number we get back from the modifying RPC op is exactly incremented by 1 from what we had previously. The data in the directory contents is in a defined format that we have to parse locally to perform lookups and readdir, so modifying isn't a problem. If the edit fails, we just clear the VALID flag on the directory and it will be reloaded next time it is needed. Signed-off-by: David Howells