From: Ralph Boehme <slow@samba.org>
Date: Thu, 4 Jan 2018 16:02:53 +0000 (+0100)
Subject: vfs_fileid: add fileid:algorithm = fsname_nodirs
X-Git-Tag: talloc-2.1.11~54
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b599cb216815415a63504ec69be3f70f08ea58d5;p=thirdparty%2Fsamba.git

vfs_fileid: add fileid:algorithm = fsname_nodirs

Enabling fileid:algorithm = fsname_nodirs uses the hostname algorithm
for directories and thus breaks cluster lock coherence for directories.

Based-on-a-patch-by: Christian Ambach <ambi@samba.org>

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
---

diff --git a/docs-xml/manpages/vfs_fileid.8.xml b/docs-xml/manpages/vfs_fileid.8.xml
index 6a09f16cf79..9e8becb6b0c 100644
--- a/docs-xml/manpages/vfs_fileid.8.xml
+++ b/docs-xml/manpages/vfs_fileid.8.xml
@@ -61,12 +61,18 @@
 		<term>fileid:algorithm = ALGORITHM</term>
 		<listitem>
 		<para>Available algorithms are <command>fsname</command>,
-		<command>fsid</command> and <command>hostname</command>. The
-		default value is <command>fsname</command>.
+		<command>fsname_nodirs</command>, <command>fsid</command> and
+		<command>hostname</command>. The default value is
+		<command>fsname</command>.
 		</para>
 		<para>The <command>fsname</command> algorithm generates
 		device id by hashing the kernel device name.
 		</para>
+		<para>The <command>fsname_nodirs</command> algorithm generates
+		device id by hashing the kernel device name for files and by hashing
+		the hostname for directories. This can be used to deliberately
+		break lock coherency for directories in a cluster.
+		</para>
 		<para>The <command>fsid</command> algorithm generates
 		the device id from the <command>f_fsid</command> returned
 		from the <command>statfs()</command> syscall.
diff --git a/source3/modules/vfs_fileid.c b/source3/modules/vfs_fileid.c
index 76f08f31a9e..4752bc55286 100644
--- a/source3/modules/vfs_fileid.c
+++ b/source3/modules/vfs_fileid.c
@@ -238,6 +238,18 @@ static uint64_t fileid_device_mapping_hostname(struct fileid_handle_data *data,
 	return id;
 }
 
+/* a device mapping using a fsname for files and hostname for dirs */
+static uint64_t fileid_device_mapping_fsname_nodirs(
+	struct fileid_handle_data *data,
+	const SMB_STRUCT_STAT *sbuf)
+{
+	if (S_ISDIR(sbuf->st_ex_mode)) {
+		return fileid_device_mapping_hostname(data, sbuf);
+	}
+
+	return fileid_device_mapping_fsname(data, sbuf);
+}
+
 /* device mapping functions using a fsid */
 static uint64_t fileid_device_mapping_fsid(struct fileid_handle_data *data,
 					   const SMB_STRUCT_STAT *sbuf)
@@ -302,6 +314,8 @@ static int fileid_connect(struct vfs_handle_struct *handle,
 					 algorithm);
 	if (strcmp("fsname", algorithm) == 0) {
 		data->device_mapping_fn	= fileid_device_mapping_fsname;
+	} else if (strcmp("fsname_nodirs", algorithm) == 0) {
+		data->device_mapping_fn = fileid_device_mapping_fsname_nodirs;
 	} else if (strcmp("fsid", algorithm) == 0) {
 		data->device_mapping_fn	= fileid_device_mapping_fsid;
 	} else if (strcmp("hostname", algorithm) == 0) {