mirror of https://gitee.com/openkylin/linux.git
cee54fc944
NFSv4 file state-changing functions such as OPEN, CLOSE, LOCK,... are all labelled with "sequence identifiers" in order to prevent the server from reordering RPC requests, as this could cause its file state to become out of sync with the client. Currently the NFS client code enforces this ordering locally using semaphores to restrict access to structures until the RPC call is done. This, of course, only works with synchronous RPC calls, since the user process must first grab the semaphore. By dropping semaphores, and instead teaching the RPC engine to hold the RPC calls until they are ready to be sent, we can extend this process to work nicely with asynchronous RPC calls too. This patch adds a new list called "rpc_sequence" that defines the order of the RPC calls to be sent. We add one such list for each state_owner. When an RPC call is ready to be sent, it checks if it is top of the rpc_sequence list. If so, it proceeds. If not, it goes back to sleep, and loops until it hits top of the list. Once the RPC call has completed, it can then bump the sequence id counter, and remove itself from the rpc_sequence list, and then wake up the next sleeper. Note that the state_owner sequence ids and lock_owner sequence ids are all indexed to the same rpc_sequence list, so OPEN, LOCK,... requests are all ordered w.r.t. each other. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> |
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| .. | ||
| Makefile | ||
| callback.c | ||
| callback.h | ||
| callback_proc.c | ||
| callback_xdr.c | ||
| delegation.c | ||
| delegation.h | ||
| dir.c | ||
| direct.c | ||
| file.c | ||
| idmap.c | ||
| inode.c | ||
| mount_clnt.c | ||
| nfs2xdr.c | ||
| nfs3acl.c | ||
| nfs3proc.c | ||
| nfs3xdr.c | ||
| nfs4_fs.h | ||
| nfs4proc.c | ||
| nfs4renewd.c | ||
| nfs4state.c | ||
| nfs4xdr.c | ||
| nfsroot.c | ||
| pagelist.c | ||
| proc.c | ||
| read.c | ||
| symlink.c | ||
| unlink.c | ||
| write.c | ||