libshare: nfs: commonify nfs_exports_[un]lock(), FILE_HEADER

Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: George Wilson <[email protected]>
Signed-off-by: Ahelenia Ziemiańska <[email protected]>
Closes #11886

1 files changed, 7 insertions, 51 deletions

diff --git a/lib/libshare/os/linux/nfs.c b/lib/libshare/os/linux/nfs.c
index a7bcbd138..08c7db1bc 100644
--- a/lib/libshare/os/linux/nfs.c
+++ b/lib/libshare/os/linux/nfs.c
@@ -42,7 +42,6 @@
 #include "libshare_impl.h"
 #include "nfs.h"
 
-#define	FILE_HEADER		"# !!! DO NOT EDIT THIS FILE MANUALLY !!!\n\n"
 #define	ZFS_EXPORTS_DIR		"/etc/exports.d"
 #define	ZFS_EXPORTS_FILE	ZFS_EXPORTS_DIR"/zfs.exports"
 #define	ZFS_EXPORTS_LOCK	ZFS_EXPORTS_FILE".lock"
@@ -55,49 +54,6 @@ typedef int (*nfs_shareopt_callback_t)(const char *opt, const char *value,
 typedef int (*nfs_host_callback_t)(const char *sharepath, const char *filename,
     const char *host, const char *security, const char *access, void *cookie);
 
-static int nfs_lock_fd = -1;
-
-/*
- * The nfs_exports_[lock|unlock] is used to guard against conconcurrent
- * updates to the exports file. Each protocol is responsible for
- * providing the necessary locking to ensure consistency.
- */
-static int
-nfs_exports_lock(void)
-{
-	int err;
-
-	nfs_lock_fd = open(ZFS_EXPORTS_LOCK,
-	    O_RDWR | O_CREAT | O_CLOEXEC, 0600);
-	if (nfs_lock_fd == -1) {
-		err = errno;
-		fprintf(stderr, "failed to lock %s: %s\n",
-		    ZFS_EXPORTS_LOCK, strerror(err));
-		return (err);
-	}
-	if (flock(nfs_lock_fd, LOCK_EX) != 0) {
-		err = errno;
-		fprintf(stderr, "failed to lock %s: %s\n",
-		    ZFS_EXPORTS_LOCK, strerror(err));
-		(void) close(nfs_lock_fd);
-		return (err);
-	}
-	return (0);
-}
-
-static void
-nfs_exports_unlock(void)
-{
-	verify(nfs_lock_fd > 0);
-
-	if (flock(nfs_lock_fd, LOCK_UN) != 0) {
-		fprintf(stderr, "failed to unlock %s: %s\n",
-		    ZFS_EXPORTS_LOCK, strerror(errno));
-	}
-	close(nfs_lock_fd);
-	nfs_lock_fd = -1;
-}
-
 /*
  * Invokes the specified callback function for each Solaris share option
  * listed in the specified string.
@@ -563,7 +519,7 @@ nfs_enable_share(sa_share_impl_t impl_share)
 	if ((filename = nfs_init_tmpfile()) == NULL)
 		return (SA_SYSTEM_ERR);
 
-	error = nfs_exports_lock();
+	error = nfs_exports_lock(ZFS_EXPORTS_LOCK);
 	if (error != 0) {
 		unlink(filename);
 		free(filename);
@@ -574,7 +530,7 @@ nfs_enable_share(sa_share_impl_t impl_share)
 	if (error != SA_OK) {
 		unlink(filename);
 		free(filename);
-		nfs_exports_unlock();
+		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 		return (error);
 	}
 
@@ -583,7 +539,7 @@ nfs_enable_share(sa_share_impl_t impl_share)
 	if (error != SA_OK) {
 		unlink(filename);
 		free(filename);
-		nfs_exports_unlock();
+		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 		return (error);
 	}
 
@@ -596,7 +552,7 @@ nfs_enable_share(sa_share_impl_t impl_share)
 		unlink(filename);
 		free(filename);
 	}
-	nfs_exports_unlock();
+	nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 	return (error);
 }
 
@@ -612,7 +568,7 @@ nfs_disable_share(sa_share_impl_t impl_share)
 	if ((filename = nfs_init_tmpfile()) == NULL)
 		return (SA_SYSTEM_ERR);
 
-	error = nfs_exports_lock();
+	error = nfs_exports_lock(ZFS_EXPORTS_LOCK);
 	if (error != 0) {
 		unlink(filename);
 		free(filename);
@@ -623,11 +579,11 @@ nfs_disable_share(sa_share_impl_t impl_share)
 	if (error != SA_OK) {
 		unlink(filename);
 		free(filename);
-		nfs_exports_unlock();
+		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 		return (error);
 	}
 	error = nfs_fini_tmpfile(filename);
-	nfs_exports_unlock();
+	nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 	return (error);
 }