From: Steve Dickson Date: Wed, 15 May 2013 18:51:49 +0000 (-0400) Subject: NFSD: Don't give out read delegations on creates X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=9a0590aec3ca5e86a64b87e004244abc4dd1faf9;p=deliverable%2Flinux.git NFSD: Don't give out read delegations on creates When an exclusive create is done with the mode bits set (aka open(testfile, O_CREAT | O_EXCL, 0777)) this causes a OPEN op followed by a SETATTR op. When a read delegation is given in the OPEN, it causes the SETATTR to delay with EAGAIN until the delegation is recalled. This patch caused exclusive creates to give out a write delegation (which turn into no delegation) which allows the SETATTR seamlessly succeed. Signed-off-by: Steve Dickson [bfields: do this for any CREATE, not just exclusive; comment] Signed-off-by: J. Bruce Fields --- diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index c4f63399832c..44dcea96bfcb 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -3113,8 +3113,17 @@ nfs4_open_delegation(struct net *net, struct svc_fh *fh, goto out; if (!cb_up || !(oo->oo_flags & NFS4_OO_CONFIRMED)) goto out; + /* + * Also, if the file was opened for write or + * create, there's a good chance the client's + * about to write to it, resulting in an + * immediate recall (since we don't support + * write delegations): + */ if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE) flag = NFS4_OPEN_DELEGATE_WRITE; + else if (open->op_create == NFS4_OPEN_CREATE) + flag = NFS4_OPEN_DELEGATE_WRITE; else flag = NFS4_OPEN_DELEGATE_READ; break;