Publish libshare protocols, use enum-based API

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #13165

lib/libshare/libshare.c

@@ -45,77 +45,63 @@
 		.sa_mountpoint = path, \
 		.sa_shareopts = shareopts, \
 	}
-#define	find_proto(pcol) \
-	/* CSTYLED */ \
-	({ \
-		sa_fstype_t prot = { \
-			.protocol = pcol, \
-		}; \
-		avl_find(&fstypes, &prot, NULL); \
-	})
 
-static avl_tree_t fstypes;
+#define	VALIDATE_PROTOCOL(proto, ...) \
+	if ((proto) < 0 || (proto) >= SA_PROTOCOL_COUNT) \
+		return __VA_ARGS__
 
-static int
-fstypes_compar(const void *lhs, const void *rhs)
-{
-	const sa_fstype_t *l = lhs, *r = rhs;
-	int cmp = strcmp(l->protocol, r->protocol);
-	return ((0 < cmp) - (cmp < 0));
-}
+const char *const sa_protocol_names[SA_PROTOCOL_COUNT] = {
+	[SA_PROTOCOL_NFS] = "nfs",
+	[SA_PROTOCOL_SMB] = "smb",
+};
 
-__attribute__((constructor)) static void
-libshare_init(void)
-{
-	avl_create(&fstypes, fstypes_compar,
-	    sizeof (sa_fstype_t), offsetof(sa_fstype_t, node));
-	avl_add(&fstypes, &libshare_nfs_type);
-	avl_add(&fstypes, &libshare_smb_type);
-}
+static const sa_fstype_t *fstypes[SA_PROTOCOL_COUNT] =
+	{&libshare_nfs_type, &libshare_smb_type};
 
 int
 sa_enable_share(const char *zfsname, const char *mountpoint,
-    const char *shareopts, const char *protocol)
+    const char *shareopts, enum sa_protocol protocol)
 {
-	sa_fstype_t *fstype = find_proto(protocol);
-	if (!fstype)
-		return (SA_INVALID_PROTOCOL);
+	VALIDATE_PROTOCOL(protocol, SA_INVALID_PROTOCOL);
 
 	const struct sa_share_impl args =
 	    init_share(zfsname, mountpoint, shareopts);
-	return (fstype->enable_share(&args));
+	return (fstypes[protocol]->enable_share(&args));
 }
 
 int
-sa_disable_share(const char *mountpoint, const char *protocol)
+sa_disable_share(const char *mountpoint, enum sa_protocol protocol)
 {
-	sa_fstype_t *fstype = find_proto(protocol);
-	if (!fstype)
-		return (SA_INVALID_PROTOCOL);
+	VALIDATE_PROTOCOL(protocol, SA_INVALID_PROTOCOL);
 
 	const struct sa_share_impl args = init_share(NULL, mountpoint, NULL);
-	return (fstype->disable_share(&args));
+	return (fstypes[protocol]->disable_share(&args));
 }
 
 boolean_t
-sa_is_shared(const char *mountpoint, const char *protocol)
+sa_is_shared(const char *mountpoint, enum sa_protocol protocol)
 {
-	sa_fstype_t *fstype = find_proto(protocol);
-	if (!fstype)
-		return (B_FALSE);
+	VALIDATE_PROTOCOL(protocol, B_FALSE);
 
 	const struct sa_share_impl args = init_share(NULL, mountpoint, NULL);
-	return (fstype->is_shared(&args));
+	return (fstypes[protocol]->is_shared(&args));
 }
 
 void
-sa_commit_shares(const char *protocol)
+sa_commit_shares(enum sa_protocol protocol)
 {
-	sa_fstype_t *fstype = find_proto(protocol);
-	if (!fstype)
-		return;
+	/* CSTYLED */
+	VALIDATE_PROTOCOL(protocol, );
 
-	fstype->commit_shares();
+	fstypes[protocol]->commit_shares();
+}
+
+int
+sa_validate_shareopts(const char *options, enum sa_protocol protocol)
+{
+	VALIDATE_PROTOCOL(protocol, SA_INVALID_PROTOCOL);
+
+	return (fstypes[protocol]->validate_shareopts(options));
 }
 
 /*
@@ -205,13 +191,3 @@ sa_errorstr(int err)
 		return (errstr);
 	}
 }
-
-int
-sa_validate_shareopts(const char *options, const char *protocol)
-{
-	sa_fstype_t *fstype = find_proto(protocol);
-	if (!fstype)
-		return (SA_INVALID_PROTOCOL);
-
-	return (fstype->validate_shareopts(options));
-}

lib/libshare/libshare_impl.h

@@ -27,8 +27,6 @@
 #ifndef _LIBSPL_LIBSHARE_IMPL_H
 #define	_LIBSPL_LIBSHARE_IMPL_H
 
-#include <sys/avl.h>
-
 typedef const struct sa_share_impl {
 	const char *sa_zfsname;
 	const char *sa_mountpoint;
@@ -36,17 +34,13 @@ typedef const struct sa_share_impl {
 } *sa_share_impl_t;
 
 typedef struct {
-	const char *protocol;
-
 	int (*const enable_share)(sa_share_impl_t share);
 	int (*const disable_share)(sa_share_impl_t share);
 	boolean_t (*const is_shared)(sa_share_impl_t share);
 	int (*const validate_shareopts)(const char *shareopts);
 	int (*const commit_shares)(void);
-
-	avl_node_t node;
 } sa_fstype_t;
 
-extern sa_fstype_t libshare_nfs_type, libshare_smb_type;
+extern const sa_fstype_t libshare_nfs_type, libshare_smb_type;
 
 #endif /* _LIBSPL_LIBSHARE_IMPL_H */

lib/libshare/os/freebsd/nfs.c

@@ -186,9 +186,7 @@ start:
 	return (SA_OK);
 }
 
-sa_fstype_t libshare_nfs_type = {
-	.protocol = "nfs",
-
+const sa_fstype_t libshare_nfs_type = {
 	.enable_share = nfs_enable_share,
 	.disable_share = nfs_disable_share,
 	.is_shared = nfs_is_shared,

lib/libshare/os/freebsd/smb.c

@@ -76,9 +76,7 @@ smb_update_shares(void)
 	return (0);
 }
 
-sa_fstype_t libshare_smb_type = {
-	.protocol = "smb",
-
+const sa_fstype_t libshare_smb_type = {
 	.enable_share = smb_enable_share,
 	.disable_share = smb_disable_share,
 	.is_shared = smb_is_share_active,

lib/libshare/os/linux/nfs.c

@@ -481,9 +481,7 @@ nfs_commit_shares(void)
 	return (libzfs_run_process(argv[0], argv, 0));
 }
 
-sa_fstype_t libshare_nfs_type = {
-	.protocol = "nfs",
-
+const sa_fstype_t libshare_nfs_type = {
 	.enable_share = nfs_enable_share,
 	.disable_share = nfs_disable_share,
 	.is_shared = nfs_is_shared,

lib/libshare/os/linux/smb.c

@@ -363,9 +363,7 @@ smb_update_shares(void)
 	return (0);
 }
 
-sa_fstype_t libshare_smb_type = {
-	.protocol = "smb",
-
+const sa_fstype_t libshare_smb_type = {
 	.enable_share = smb_enable_share,
 	.disable_share = smb_disable_share,
 	.is_shared = smb_is_share_active,