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| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2013-02-07 16:54:07 +0100 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2013-02-11 21:33:13 +0100 |
| commit | 65b62a29f719e937b5be1df472287f4c61e53ac6 (patch) | |
| tree | ea6b552a08883d92cfedb891044fa9697cbc5619 /fs/nfs/nfs4proc.c | |
| parent | NFSv4: Fix up the return values of nfs4_open_delegation_recall (diff) | |
| download | linux-65b62a29f719e937b5be1df472287f4c61e53ac6.tar.xz linux-65b62a29f719e937b5be1df472287f4c61e53ac6.zip | |
NFSv4: Ensure delegation recall and byte range lock removal don't conflict
Add a mutex to the struct nfs4_state_owner to ensure that delegation
recall doesn't conflict with byte range lock removal.
Note that we nest the new mutex _outside_ the state manager reclaim
protection (nfsi->rwsem) in order to avoid deadlocks.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/nfs4proc.c')
| -rw-r--r-- | fs/nfs/nfs4proc.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index f7e05ade5572..d51227371c67 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -4485,7 +4485,9 @@ static struct rpc_task *nfs4_do_unlck(struct file_lock *fl, static int nfs4_proc_unlck(struct nfs4_state *state, int cmd, struct file_lock *request) { - struct nfs_inode *nfsi = NFS_I(state->inode); + struct inode *inode = state->inode; + struct nfs4_state_owner *sp = state->owner; + struct nfs_inode *nfsi = NFS_I(inode); struct nfs_seqid *seqid; struct nfs4_lock_state *lsp; struct rpc_task *task; @@ -4495,12 +4497,17 @@ static int nfs4_proc_unlck(struct nfs4_state *state, int cmd, struct file_lock * status = nfs4_set_lock_state(state, request); /* Unlock _before_ we do the RPC call */ request->fl_flags |= FL_EXISTS; + /* Exclude nfs_delegation_claim_locks() */ + mutex_lock(&sp->so_delegreturn_mutex); + /* Exclude nfs4_reclaim_open_stateid() - note nesting! */ down_read(&nfsi->rwsem); if (do_vfs_lock(request->fl_file, request) == -ENOENT) { up_read(&nfsi->rwsem); + mutex_unlock(&sp->so_delegreturn_mutex); goto out; } up_read(&nfsi->rwsem); + mutex_unlock(&sp->so_delegreturn_mutex); if (status != 0) goto out; /* Is this a delegated lock? */ |