Add an nfssvc() option to the kernel for the new NFS client

which dumps out the actual options being used by an NFS mount.
This will be used to implement a "-m" option for nfsstat(1).

Reviewed by:	alfred
MFC after:	2 weeks

3 files changed, 128 insertions, 0 deletions

diff --git a/sys/fs/nfs/nfs_var.h b/sys/fs/nfs/nfs_var.h
index e5bacb2..8e68d42 100644
--- a/sys/fs/nfs/nfs_var.h
+++ b/sys/fs/nfs/nfs_var.h
@@ -313,6 +313,7 @@ void nfsd_init(void);
 int nfsd_checkrootexp(struct nfsrv_descript *);
 
 /* nfs_clvfsops.c */
+void nfscl_retopts(struct nfsmount *, char *, size_t);
 
 /* nfs_commonport.c */
 int nfsrv_checksockseqnum(struct socket *, tcp_seq);
diff --git a/sys/fs/nfsclient/nfs_clport.c b/sys/fs/nfsclient/nfs_clport.c
index 1cbf325..fe28975 100644
--- a/sys/fs/nfsclient/nfs_clport.c
+++ b/sys/fs/nfsclient/nfs_clport.c
@@ -1201,6 +1201,9 @@ nfssvc_nfscl(struct thread *td, struct nfssvc_args *uap)
 	struct nfscbd_args nfscbdarg;
 	struct nfsd_nfscbd_args nfscbdarg2;
 	int error;
+	struct nameidata nd;
+	struct nfscl_dumpmntopts dumpmntopts;
+	char *buf;
 
 	if (uap->flag & NFSSVC_CBADDSOCK) {
 		error = copyin(uap->argp, (caddr_t)&nfscbdarg, sizeof(nfscbdarg));
@@ -1233,6 +1236,28 @@ nfssvc_nfscl(struct thread *td, struct nfssvc_args *uap)
 		if (error)
 			return (error);
 		error = nfscbd_nfsd(td, &nfscbdarg2);
+	} else if (uap->flag & NFSSVC_DUMPMNTOPTS) {
+		error = copyin(uap->argp, &dumpmntopts, sizeof(dumpmntopts));
+		if (error == 0 && (dumpmntopts.ndmnt_blen < 256 ||
+		    dumpmntopts.ndmnt_blen > 1024))
+			error = EINVAL;
+		if (error == 0)
+			error = nfsrv_lookupfilename(&nd,
+			    dumpmntopts.ndmnt_fname, td);
+		if (error == 0 && strcmp(nd.ni_vp->v_mount->mnt_vfc->vfc_name,
+		    "nfs") != 0) {
+			vput(nd.ni_vp);
+			error = EINVAL;
+		}
+		if (error == 0) {
+			buf = malloc(dumpmntopts.ndmnt_blen, M_TEMP, M_WAITOK);
+			nfscl_retopts(VFSTONFS(nd.ni_vp->v_mount), buf,
+			    dumpmntopts.ndmnt_blen);
+			vput(nd.ni_vp);
+			error = copyout(buf, dumpmntopts.ndmnt_buf,
+			    dumpmntopts.ndmnt_blen);
+			free(buf, M_TEMP);
+		}
 	} else {
 		error = EINVAL;
 	}
diff --git a/sys/fs/nfsclient/nfs_clvfsops.c b/sys/fs/nfsclient/nfs_clvfsops.c
index 71791fa..41a6b78 100644
--- a/sys/fs/nfsclient/nfs_clvfsops.c
+++ b/sys/fs/nfsclient/nfs_clvfsops.c
@@ -1627,3 +1627,105 @@ nfs_getnlminfo(struct vnode *vp, uint8_t *fhp, size_t *fhlenp,
 	}
 }
 
+/*
+ * This function prints out an option name, based on the conditional
+ * argument.
+ */
+static __inline void nfscl_printopt(struct nfsmount *nmp, int testval,
+    char *opt, char **buf, size_t *blen)
+{
+	int len;
+
+	if (testval != 0 && *blen > strlen(opt)) {
+		len = snprintf(*buf, *blen, "%s", opt);
+		if (len != strlen(opt))
+			printf("EEK!!\n");
+		*buf += len;
+		*blen -= len;
+	}
+}
+
+/*
+ * This function printf out an options integer value.
+ */
+static __inline void nfscl_printoptval(struct nfsmount *nmp, int optval,
+    char *opt, char **buf, size_t *blen)
+{
+	int len;
+
+	if (*blen > strlen(opt) + 1) {
+		/* Could result in truncated output string. */
+		len = snprintf(*buf, *blen, "%s=%d", opt, optval);
+		if (len < *blen) {
+			*buf += len;
+			*blen -= len;
+		}
+	}
+}
+
+/*
+ * Load the option flags and values into the buffer.
+ */
+void nfscl_retopts(struct nfsmount *nmp, char *buffer, size_t buflen)
+{
+	char *buf;
+	size_t blen;
+
+	buf = buffer;
+	blen = buflen;
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_NFSV4) != 0, "nfsv4", &buf,
+	    &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_NFSV3) != 0, "nfsv3", &buf,
+	    &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & (NFSMNT_NFSV3 | NFSMNT_NFSV4)) == 0,
+	    "nfsv2", &buf, &blen);
+	nfscl_printopt(nmp, nmp->nm_sotype == SOCK_STREAM, ",tcp", &buf, &blen);
+	nfscl_printopt(nmp, nmp->nm_sotype != SOCK_STREAM, ",udp", &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_RESVPORT) != 0, ",resvport",
+	    &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_NOCONN) != 0, ",noconn",
+	    &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_SOFT) == 0, ",hard", &buf,
+	    &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_SOFT) != 0, ",soft", &buf,
+	    &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_INT) != 0, ",intr", &buf,
+	    &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_NOCTO) == 0, ",cto", &buf,
+	    &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_NOCTO) != 0, ",nocto", &buf,
+	    &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & (NFSMNT_NOLOCKD | NFSMNT_NFSV4)) ==
+	    0, ",lockd", &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & (NFSMNT_NOLOCKD | NFSMNT_NFSV4)) ==
+	    NFSMNT_NOLOCKD, ",nolockd", &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_RDIRPLUS) != 0, ",rdirplus",
+	    &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & NFSMNT_KERB) == 0, ",sec=sys",
+	    &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & (NFSMNT_KERB | NFSMNT_INTEGRITY |
+	    NFSMNT_PRIVACY)) == NFSMNT_KERB, ",sec=krb5", &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & (NFSMNT_KERB | NFSMNT_INTEGRITY |
+	    NFSMNT_PRIVACY)) == (NFSMNT_KERB | NFSMNT_INTEGRITY), ",sec=krb5i",
+	    &buf, &blen);
+	nfscl_printopt(nmp, (nmp->nm_flag & (NFSMNT_KERB | NFSMNT_INTEGRITY |
+	    NFSMNT_PRIVACY)) == (NFSMNT_KERB | NFSMNT_PRIVACY), ",sec=krb5p",
+	    &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_acdirmin, ",acdirmin", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_acdirmax, ",acdirmax", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_acregmin, ",acregmin", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_acregmax, ",acregmax", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_nametimeo, ",nametimeo", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_negnametimeo, ",negnametimeo", &buf,
+	    &blen);
+	nfscl_printoptval(nmp, nmp->nm_rsize, ",rsize", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_wsize, ",wsize", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_readdirsize, ",readdirsize", &buf,
+	    &blen);
+	nfscl_printoptval(nmp, nmp->nm_readahead, ",readahead", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_wcommitsize, ",wcommitsize", &buf,
+	    &blen);
+	nfscl_printoptval(nmp, nmp->nm_timeo, ",timeout", &buf, &blen);
+	nfscl_printoptval(nmp, nmp->nm_retry, ",retrans", &buf, &blen);
+}
+