smb: client: reuse file lease key in compound operations
Currently, when a rename, unlink or set path size compound operation is requested on a file that has a lot of dirty pages to be written to the server, we do not send the lease key for these requests. As a result, the server can assume that this request is from a new client, and send a lease break notification to the same client, on the same connection. As a response to the lease break, the client can consume several credits to write the dirty pages to the server. Depending on the server's credit grant implementation, the server can stop granting more credits to this connection, and this can cause a deadlock (which can only be resolved when the lease timer on the server expires). One of the problems here is that the client is sending no lease key, even if it has a lease for the file. This patch fixes the problem by reusing the existing lease key on the file for rename, unlink and set path size compound operations so that the client does not break its own lease. A very trivial example could be a set of commands by a client that maintains open handle (for write) to a file and then tries to copy the contents of that file to another one, eg., tail -f /dev/null > myfile & mv myfile myfile2 Presently, the network capture on the client shows that the move (or rename) would trigger a lease break on the same client, for the same file. With the lease key reused, the lease break request-response overhead is eliminated, thereby reducing the roundtrips performed for this set of operations. The patch fixes the bug described above and also provides perf benefit. Signed-off-by: Meetakshi Setiya <msetiya@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
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