[PATCH 1/1] NFSD: release read access of nfs4_file when a write delegation is returned

[PATCH 1/1] NFSD: release read access of nfs4_file when a write delegation is returned

[Dai Ngo]

When a write delegation is returned, check if read access was added
to nfs4_file when client opens file with WRONLY, and release it.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
---
 fs/nfsd/nfs4state.c | 9 ++++++++-
 fs/nfsd/state.h     | 1 +
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 2bd63594d8da..5e47d9f85ab5 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1207,14 +1207,19 @@ nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid)
 static void put_deleg_file(struct nfs4_file *fp)
 {
 	struct nfsd_file *nf = NULL;
+	struct nfsd_file *rnf = NULL;
 
 	spin_lock(&fp->fi_lock);
-	if (--fp->fi_delegees == 0)
+	if (--fp->fi_delegees == 0) {
 		swap(nf, fp->fi_deleg_file);
+		swap(rnf, fp->fi_rdeleg_file);
+	}
 	spin_unlock(&fp->fi_lock);
 
 	if (nf)
 		nfsd_file_put(nf);
+	if (rnf)
+		nfs4_file_put_access(fp, NFS4_SHARE_ACCESS_READ);
 }
 
 static void nfs4_unlock_deleg_lease(struct nfs4_delegation *dp)
@@ -4738,6 +4743,7 @@ static void nfsd4_file_init(const struct svc_fh *fh, struct nfs4_file *fp)
 	INIT_LIST_HEAD(&fp->fi_clnt_odstate);
 	fh_copy_shallow(&fp->fi_fhandle, &fh->fh_handle);
 	fp->fi_deleg_file = NULL;
+	fp->fi_rdeleg_file = NULL;
 	fp->fi_had_conflict = false;
 	fp->fi_share_deny = 0;
 	memset(fp->fi_fds, 0, sizeof(fp->fi_fds));
@@ -6171,6 +6177,7 @@ nfsd4_add_rdaccess_to_wrdeleg(struct svc_rqst *rqstp, struct nfsd4_open *open,
 		__nfs4_file_get_access(fp, NFS4_SHARE_ACCESS_READ);
 		fp = stp->st_stid.sc_file;
 		fp->fi_fds[O_RDONLY] = nf;
+		fp->fi_rdeleg_file = nf;
 		spin_unlock(&fp->fi_lock);
 	}
 	return true;
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 1995bca158b8..8adc2550129e 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -665,6 +665,7 @@ struct nfs4_file {
 	atomic_t		fi_access[2];
 	u32			fi_share_deny;
 	struct nfsd_file	*fi_deleg_file;
+	struct nfsd_file	*fi_rdeleg_file;
 	int			fi_delegees;
 	struct knfsd_fh		fi_fhandle;
 	bool			fi_had_conflict;
-- 
2.43.5

Re: [PATCH 1/1] NFSD: release read access of nfs4_file when a write delegation is returned

[Jeff Layton]

On Tue, 2025-05-13 at 09:10 -0700, Dai Ngo wrote:
> When a write delegation is returned, check if read access was added
> to nfs4_file when client opens file with WRONLY, and release it.
> 
> Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
> ---
>  fs/nfsd/nfs4state.c | 9 ++++++++-
>  fs/nfsd/state.h     | 1 +
>  2 files changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 2bd63594d8da..5e47d9f85ab5 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -1207,14 +1207,19 @@ nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid)
>  static void put_deleg_file(struct nfs4_file *fp)
>  {
>  	struct nfsd_file *nf = NULL;
> +	struct nfsd_file *rnf = NULL;
>  
>  	spin_lock(&fp->fi_lock);
> -	if (--fp->fi_delegees == 0)
> +	if (--fp->fi_delegees == 0) {
>  		swap(nf, fp->fi_deleg_file);
> +		swap(rnf, fp->fi_rdeleg_file);
> +	}
>  	spin_unlock(&fp->fi_lock);
>  
>  	if (nf)
>  		nfsd_file_put(nf);
> +	if (rnf)
> +		nfs4_file_put_access(fp, NFS4_SHARE_ACCESS_READ);
>  }
>  
>  static void nfs4_unlock_deleg_lease(struct nfs4_delegation *dp)
> @@ -4738,6 +4743,7 @@ static void nfsd4_file_init(const struct svc_fh *fh, struct nfs4_file *fp)
>  	INIT_LIST_HEAD(&fp->fi_clnt_odstate);
>  	fh_copy_shallow(&fp->fi_fhandle, &fh->fh_handle);
>  	fp->fi_deleg_file = NULL;
> +	fp->fi_rdeleg_file = NULL;
>  	fp->fi_had_conflict = false;
>  	fp->fi_share_deny = 0;
>  	memset(fp->fi_fds, 0, sizeof(fp->fi_fds));
> @@ -6171,6 +6177,7 @@ nfsd4_add_rdaccess_to_wrdeleg(struct svc_rqst *rqstp, struct nfsd4_open *open,
>  		__nfs4_file_get_access(fp, NFS4_SHARE_ACCESS_READ);
>  		fp = stp->st_stid.sc_file;
>  		fp->fi_fds[O_RDONLY] = nf;
> +		fp->fi_rdeleg_file = nf;
>  		spin_unlock(&fp->fi_lock);
>  	}
>  	return true;
> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
> index 1995bca158b8..8adc2550129e 100644
> --- a/fs/nfsd/state.h
> +++ b/fs/nfsd/state.h
> @@ -665,6 +665,7 @@ struct nfs4_file {
>  	atomic_t		fi_access[2];
>  	u32			fi_share_deny;
>  	struct nfsd_file	*fi_deleg_file;
> +	struct nfsd_file	*fi_rdeleg_file;
>  	int			fi_delegees;
>  	struct knfsd_fh		fi_fhandle;
>  	bool			fi_had_conflict;

Reviewed-by: Jeff Layton <jlayton@kernel.org>

Re: [PATCH 1/1] NFSD: release read access of nfs4_file when a write delegation is returned

[Chuck Lever]

On Tue, 13 May 2025 09:10:51 -0700, Dai Ngo wrote:
> When a write delegation is returned, check if read access was added
> to nfs4_file when client opens file with WRONLY, and release it.
> 

Applied to nfsd-testing, thanks!

The extra nfsd_file pointers in struct nfs4_file are confusing, and
have been noted for future clean-up.

[1/1] NFSD: release read access of nfs4_file when a write delegation is returned
      commit: 65de35b2b4b5cff421f48e638010a2f8cecbc62e

--
Chuck Lever <chuck.lever@oracle.com>