NFS: Allow NFSROOT debugging messages to be enabled dynamically

As a convenience, introduce a kernel command line option to enable NFSROOT debugging messages. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Allow NFSROOT debugging messages to be enabled dynamically
As a convenience, introduce a kernel command line option to enable NFSROOT debugging messages. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Chuck Lever · Trond Myklebust
1 parent 8d23210378
Showing 3 changed files with 39 additions and 7 deletions Side-by-side Diff
Documentation/filesystems/nfs/nfsroot.txt
Documentation/kernel-parameters.txt
fs/nfs/nfsroot.c
@@ -159,6 +159,28 @@
                 Default: any
  
  
+nfsrootdebug
+
+  This parameter enables debugging messages to appear in the kernel
+  log at boot time so that administrators can verify that the correct
+  NFS mount options, server address, and root path are passed to the
+  NFS client.
+
+
+rdinit=<executable file>
+
+  To specify which file contains the program that starts system
+  initialization, administrators can use this command line parameter.
+  The default value of this parameter is "/init".  If the specified
+  file exists and the kernel can execute it, root filesystem related
+  kernel command line parameters, including `nfsroot=', are ignored.
+
+  A description of the process of mounting the root file system can be
+  found in:
+
+    Documentation/early-userspace/README
+
+
  
  
 3.) Boot Loader
@@ -1532,10 +1532,13 @@
 			1 to enable accounting
 			Default value is 0.
  
-	nfsaddrs=	[NFS]
+	nfsaddrs=	[NFS] Deprecated.  Use ip= instead.
 			See Documentation/filesystems/nfs/nfsroot.txt.
  
 	nfsroot=	[NFS] nfs root filesystem for disk-less boxes.
+			See Documentation/filesystems/nfs/nfsroot.txt.
+
+	nfsrootdebug	[NFS] enable nfsroot debugging messages.
 			See Documentation/filesystems/nfs/nfsroot.txt.
  
 	nfs.callback_tcpport=
@@ -67,6 +67,7 @@
  *				NFS over TCP.
  *	Fabian Frederick:	Option parser rebuilt (using parser lib)
  *	Chuck Lever	:	Use super.c's text-based mount option parsing
+ *	Chuck Lever	:	Add "nfsrootdebug".
  */
  
 #include <linux/types.h>
@@ -80,8 +81,6 @@
  
 #include "internal.h"
  
-/* Define this to allow debugging output */
-#undef NFSROOT_DEBUG
 #define NFSDBG_FACILITY NFSDBG_ROOT
  
 /* Default path we try to mount. "%s" gets replaced by our IP address */
@@ -103,6 +102,18 @@
 static char nfs_root_device[NFS_MAXPATHLEN + 1] __initdata = "";
  
 /*
+ * When the "nfsrootdebug" kernel command line option is specified,
+ * enable debugging messages for NFSROOT.
+ */
+static int __init nfs_root_debug(char *__unused)
+{
+	nfs_debug |= NFSDBG_ROOT | NFSDBG_MOUNT;
+	return 1;
+}
+
+__setup("nfsrootdebug", nfs_root_debug);
+
+/*
  *  Parse NFS server and directory information passed on the kernel
  *  command line.
  *
@@ -282,10 +293,6 @@
  */
 int __init nfs_root_data(char **root_device, char **root_data)
 {
-#ifdef NFSROOT_DEBUG
-	nfs_debug |= NFSDBG_ROOT | NFSDBG_MOUNT;
-#endif	/* NFSROOT_DEBUG */
-
 	servaddr = root_server_addr;
 	if (servaddr == htonl(INADDR_NONE)) {
 		printk(KERN_ERR "Root-NFS: no NFS server address\n");
...	...	@@ -159,6 +159,28 @@
159	159	Default: any
160	160
161	161
	162	+nfsrootdebug
	163	+
	164	+ This parameter enables debugging messages to appear in the kernel
	165	+ log at boot time so that administrators can verify that the correct
	166	+ NFS mount options, server address, and root path are passed to the
	167	+ NFS client.
	168	+
	169	+
	170	+rdinit=<executable file>
	171	+
	172	+ To specify which file contains the program that starts system
	173	+ initialization, administrators can use this command line parameter.
	174	+ The default value of this parameter is "/init". If the specified
	175	+ file exists and the kernel can execute it, root filesystem related
	176	+ kernel command line parameters, including `nfsroot=', are ignored.
	177	+
	178	+ A description of the process of mounting the root file system can be
	179	+ found in:
	180	+
	181	+ Documentation/early-userspace/README
	182	+
	183	+
162	184
163	185
164	186	3.) Boot Loader
...	...	@@ -1532,10 +1532,13 @@
1532	1532	1 to enable accounting
1533	1533	Default value is 0.
1534	1534
1535		- nfsaddrs= [NFS]
	1535	+ nfsaddrs= [NFS] Deprecated. Use ip= instead.
1536	1536	See Documentation/filesystems/nfs/nfsroot.txt.
1537	1537
1538	1538	nfsroot= [NFS] nfs root filesystem for disk-less boxes.
	1539	+ See Documentation/filesystems/nfs/nfsroot.txt.
	1540	+
	1541	+ nfsrootdebug [NFS] enable nfsroot debugging messages.
1539	1542	See Documentation/filesystems/nfs/nfsroot.txt.
1540	1543
1541	1544	nfs.callback_tcpport=
...	...	@@ -67,6 +67,7 @@
67	67	* NFS over TCP.
68	68	* Fabian Frederick: Option parser rebuilt (using parser lib)
69	69	* Chuck Lever : Use super.c's text-based mount option parsing
	70	+ * Chuck Lever : Add "nfsrootdebug".
70	71	*/
71	72
72	73	#include <linux/types.h>
...	...	@@ -80,8 +81,6 @@
80	81
81	82	#include "internal.h"
82	83
83		-/* Define this to allow debugging output */
84		-#undef NFSROOT_DEBUG
85	84	#define NFSDBG_FACILITY NFSDBG_ROOT
86	85
87	86	/* Default path we try to mount. "%s" gets replaced by our IP address */
...	...	@@ -103,6 +102,18 @@
103	102	static char nfs_root_device[NFS_MAXPATHLEN + 1] __initdata = "";
104	103
105	104	/*
	105	+ * When the "nfsrootdebug" kernel command line option is specified,
	106	+ * enable debugging messages for NFSROOT.
	107	+ */
	108	+static int __init nfs_root_debug(char *__unused)
	109	+{
	110	+ nfs_debug \|= NFSDBG_ROOT \| NFSDBG_MOUNT;
	111	+ return 1;
	112	+}
	113	+
	114	+__setup("nfsrootdebug", nfs_root_debug);
	115	+
	116	+/*
106	117	* Parse NFS server and directory information passed on the kernel
107	118	* command line.
108	119	*
...	...	@@ -282,10 +293,6 @@
282	293	*/
283	294	int __init nfs_root_data(char root_device, char root_data)
284	295	{
285		-#ifdef NFSROOT_DEBUG
286		- nfs_debug \|= NFSDBG_ROOT \| NFSDBG_MOUNT;
287		-#endif /* NFSROOT_DEBUG */
288		-
289	296	servaddr = root_server_addr;
290	297	if (servaddr == htonl(INADDR_NONE)) {
291	298	printk(KERN_ERR "Root-NFS: no NFS server address\n");