[PATCH RFC v2 10/28] nfsd: allow filecache to hold S_IFDIR files

Jeff Layton
2025-06-02T14:02:43Z

The filecache infrastructure will only handle S_ISREG files at the
moment. Plumb a "type" variable into nfsd_file_do_acquire and have all
of the existing callers set it to S_ISREG. Add a new
nfsd_file_acquire_dir() wrapper that we can then call to request a
nfsd_file that holds a directory open.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
fs/nfsd/filecache.c | 50 ++++++++++++++++++++++++++++++++++++++------------
fs/nfsd/filecache.h | 2 ++
fs/nfsd/vfs.c | 5 +++--
fs/nfsd/vfs.h | 2 +-
4 files changed, 44 insertions(+), 15 deletions(-)

diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index ab85e6a2454f4c783fcb1175ebbeb63a31519c18..3468883146afc080d2b4862e6002b2c6ff7315b9 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -1049,7 +1049,7 @@ nfsd_file_do_acquire(struct svc_rqst *rqstp, struct net *net,
struct auth_domain *client,
struct svc_fh *fhp,
unsigned int may_flags, struct file *file,
- struct nfsd_file **pnf, bool want_gc)
+ umode_t type, bool want_gc, struct nfsd_file **pnf)
{
unsigned char need = may_flags & NFSD_FILE_MAY_MASK;
struct nfsd_file *new, *nf;
@@ -1060,13 +1060,13 @@ nfsd_file_do_acquire(struct svc_rqst *rqstp, struct net *net,
int ret;

retry:
- if (rqstp) {
- status = fh_verify(rqstp, fhp, S_IFREG,
+ if (rqstp)
+ status = fh_verify(rqstp, fhp, type,
may_flags|NFSD_MAY_OWNER_OVERRIDE);
- } else {
- status = fh_verify_local(net, cred, client, fhp, S_IFREG,
+ else
+ status = fh_verify_local(net, cred, client, fhp, type,
may_flags|NFSD_MAY_OWNER_OVERRIDE);
- }
+
if (status != nfs_ok)
return status;
inode = d_inode(fhp->fh_dentry);
@@ -1147,7 +1147,7 @@ nfsd_file_do_acquire(struct svc_rqst *rqstp, struct net *net,
status = nfs_ok;
trace_nfsd_file_opened(nf, status);
} else {
- ret = nfsd_open_verified(fhp, may_flags, &nf->nf_file);
+ ret = nfsd_open_verified(fhp, type, may_flags, &nf->nf_file);
if (ret == -EOPENSTALE && stale_retry) {
stale_retry = false;
nfsd_file_unhash(nf);
@@ -1207,7 +1207,7 @@ nfsd_file_acquire_gc(struct svc_rqst *rqstp, struct svc_fh *fhp,
unsigned int may_flags, struct nfsd_file **pnf)
{
return nfsd_file_do_acquire(rqstp, SVC_NET(rqstp), NULL, NULL,
- fhp, may_flags, NULL, pnf, true);
+ fhp, may_flags, NULL, S_IFREG, true, pnf);
}

/**
@@ -1232,7 +1232,7 @@ nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
unsigned int may_flags, struct nfsd_file **pnf)
{
return nfsd_file_do_acquire(rqstp, SVC_NET(rqstp), NULL, NULL,
- fhp, may_flags, NULL, pnf, false);
+ fhp, may_flags, NULL, S_IFREG, false, pnf);
}

/**
@@ -1275,8 +1275,8 @@ nfsd_file_acquire_local(struct net *net, struct svc_cred *cred,
const struct cred *save_cred = get_current_cred();
__be32 beres;

- beres = nfsd_file_do_acquire(NULL, net, cred, client,
- fhp, may_flags, NULL, pnf, false);
+ beres = nfsd_file_do_acquire(NULL, net, cred, client, fhp, may_flags,
+ NULL, S_IFREG, false, pnf);
put_cred(revert_creds(save_cred));
return beres;
}
@@ -1305,7 +1305,33 @@ nfsd_file_acquire_opened(struct svc_rqst *rqstp, struct svc_fh *fhp,
struct nfsd_file **pnf)
{
return nfsd_file_do_acquire(rqstp, SVC_NET(rqstp), NULL, NULL,
- fhp, may_flags, file, pnf, false);
+ fhp, may_flags, file, S_IFREG, false, pnf);
+}
+
+/**
+ * nfsd_file_acquire_dir - Get a struct nfsd_file with an open directory
+ * @rqstp: the RPC transaction being executed
+ * @fhp: the NFS filehandle of the file to be opened
+ * @pnf: OUT: new or found "struct nfsd_file" object
+ *
+ * The nfsd_file_object returned by this API is reference-counted
+ * but not garbage-collected. The object is unhashed after the
+ * final nfsd_file_put(). This opens directories only, and only
+ * in O_RDONLY mode.
+ *
+ * Return values:
+ * %nfs_ok - @pnf points to an nfsd_file with its reference
+ * count boosted.
+ *
+ * On error, an nfsstat value in network byte order is returned.
+ */
+__be32
+nfsd_file_acquire_dir(struct svc_rqst *rqstp, struct svc_fh *fhp,
+ struct nfsd_file **pnf)
+{
+ return nfsd_file_do_acquire(rqstp, SVC_NET(rqstp), NULL, NULL, fhp,
+ NFSD_MAY_READ|NFSD_MAY_64BIT_COOKIE,
+ NULL, S_IFDIR, false, pnf);
}

/*
diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h
index 5865f9c7271214de7269ab33480689cd61c1c552..3717503f6b75462c7afca6216d9c915e055b117d 100644
--- a/fs/nfsd/filecache.h
+++ b/fs/nfsd/filecache.h
@@ -78,5 +78,7 @@ __be32 nfsd_file_acquire_opened(struct svc_rqst *rqstp, struct svc_fh *fhp,
__be32 nfsd_file_acquire_local(struct net *net, struct svc_cred *cred,
struct auth_domain *client, struct svc_fh *fhp,
unsigned int may_flags, struct nfsd_file **pnf);
+__be32 nfsd_file_acquire_dir(struct svc_rqst *rqstp, struct svc_fh *fhp,
+ struct nfsd_file **pnf);
int nfsd_file_cache_stats_show(struct seq_file *m, void *v);
#endif /* _FS_NFSD_FILECACHE_H */
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index cd689df2ca5d7396cffb5ed9dc14f774a8f3881c..86873662925e2f50823d4ce371f1018b749b4c6d 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -949,15 +949,16 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type,
/**
* nfsd_open_verified - Open a regular file for the filecache
* @fhp: NFS filehandle of the file to open
+ * @type: S_IFMT inode type allowed (0 means any type is allowed)
* @may_flags: internal permission flags
* @filp: OUT: open "struct file *"
*
* Returns zero on success, or a negative errno value.
*/
int
-nfsd_open_verified(struct svc_fh *fhp, int may_flags, struct file **filp)
+nfsd_open_verified(struct svc_fh *fhp, umode_t type, int may_flags, struct file **filp)
{
- return __nfsd_open(fhp, S_IFREG, may_flags, filp);
+ return __nfsd_open(fhp, type, may_flags, filp);
}

/*
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index eff04959606fe55c141ab4a2eed97c7e0716a5f5..9c309cdee6c491d445d56cdc6133f37248ab4b46 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -114,7 +114,7 @@ __be32 nfsd_setxattr(struct svc_rqst *rqstp, struct svc_fh *fhp,
int nfsd_open_break_lease(struct inode *, int);
__be32 nfsd_open(struct svc_rqst *, struct svc_fh *, umode_t,
int, struct file **);
-int nfsd_open_verified(struct svc_fh *fhp, int may_flags,
+int nfsd_open_verified(struct svc_fh *fhp, umode_t type, int may_flags,
struct file **filp);
__be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
struct file *file, loff_t offset,

--
2.49.0