[Yaffs] Re: Squelch mount-time debug messages by default

[John M Cavallo]

> > 
> > On Friday 04 November 2005 14:33, Todd Poynor wrote:
> > > Modify tracing of yaffs_GutsInitialise entry/exit messages from
> > > TRACE_ALWAYS to TRACE_TRACING (assuming this is an intended use of
> > that
> > > trace flag).
> > 
> > Thanx
> > 
> > Will change this. The current flag usage is a bit unruly.
> > 
> > I might concoct a better trace flag layout at some stage.
> > 
> > BTW:
> > 
> > Does anyone have a simple proc_write that could be hacked/patched
> > into 
> > yaffsfs.c to allow the tracemask to be modified dynamically with
> > something 
> > like:
> > 
> > 
> > # echo FFFFFFFF > /proc/yaffs
> > 
> > ?
> > 
> > -- Charles
> > 
> 
> Charles,
> 
> I have two versions of this type of thing, one simple for the user the
> other simple for the programmer. I am attaching the latter. I find it
> easier because I can give it the logical name of the flag rather than
> it's bit position.
> 
> In this one the flags can be set or cleared by echoing the name of the
> flag into /proc/yaffs with a '+' or '-':
> 
> echo +os-write > /proc/yaffs
> 
> It can be set to to all or none using '=', and then flags can be added
> or removed:
> 
> echo =none+os+write > /proc/yaffs
> 
> And you can use numerical values, if you are so inclined (using standard
> c format):
> 
> echo 0xf00001 > /proc/yaffs
> 
> It runs fine on my system, but when I went to add it to the latest
> version of Yaffs on the web (as of 9 Dec) I found some differences in
> other parts of the file that prevented compilation.
> 
> Yeah, I might have gone overboard with this. If you want, I can clean up
> the other version and make it available as well.
> 
> John

Looks like the patch didn't come through as an attachment. Trying again in-line.


--- linux.orig/fs/yaffs2/yaffs_fs.c	2005-12-09 14:53:01.172020203 -0500
+++ linux/fs/yaffs2/yaffs_fs.c	2005-12-09 15:00:21.941586939 -0500
@@ -48,6 +48,7 @@
 #include <linux/mtd/mtd.h>
 #include <linux/interrupt.h>
 #include <linux/string.h>
+#include <linux/ctype.h>
 
 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
 
@@ -1675,6 +1676,120 @@
 	return buf - page < count ? buf - page : count;
 }
 
+/**
+ * Set the verbosity of the warnings and error messages.
+ *
+ */
+
+static struct {
+	char *mask_name;
+	unsigned mask_bitfield;
+} mask_flags[] = {
+	{"allocate", YAFFS_TRACE_ALLOCATE},
+	{"always", YAFFS_TRACE_ALWAYS},
+	{"bad_blocks", YAFFS_TRACE_BAD_BLOCKS},
+	{"buffers", YAFFS_TRACE_BUFFERS},
+	{"bug", YAFFS_TRACE_BUG},
+	{"deletion", YAFFS_TRACE_DELETION},
+	{"erase", YAFFS_TRACE_ERASE},
+	{"error", YAFFS_TRACE_ERROR},
+	{"gc_detail", YAFFS_TRACE_GC_DETAIL},
+	{"gc", YAFFS_TRACE_GC},
+	{"mtd", YAFFS_TRACE_MTD},
+	{"nandaccess", YAFFS_TRACE_NANDACCESS},
+	{"os", YAFFS_TRACE_OS},
+	{"scan_debug", YAFFS_TRACE_SCAN_DEBUG},
+	{"scan", YAFFS_TRACE_SCAN},
+	{"tracing", YAFFS_TRACE_TRACING},
+	{"write", YAFFS_TRACE_WRITE},
+	{"all", 0xffffffff},
+	{"none", 0},
+	{NULL, 0},
+};
+
+static int yaffs_proc_write(struct file *file, const char *buf,
+					 unsigned long count, void *data)
+{
+	unsigned rg = 0, mask_bitfield;
+	char *end, *mask_name;
+	int i;
+	int done = 0;
+	int add, len;
+	int pos = 0;
+
+	rg = yaffs_traceMask;
+	
+	while (!done && (pos < count)) {
+		done = 1;
+		while ((pos < count) && isspace(buf[pos])) {
+			pos++;
+		}
+
+		switch (buf[pos]) {
+		case '+':
+		case '-':
+		case '=':
+			add = buf[pos];
+			pos++;
+			break;
+
+		default:
+			add = ' ';
+			break;
+		}
+		mask_name = NULL;
+		mask_bitfield = simple_strtoul(buf + pos, &end, 0);
+		if (end > buf + pos) {
+			mask_name = "numeral";
+			len = end - (buf + pos);
+			done = 0;
+		} else {
+
+			for (i = 0; mask_flags[i].mask_name != NULL; i++) {
+				len = strlen(mask_flags[i].mask_name);
+				if (strncmp(buf + pos, mask_flags[i].mask_name, len) == 0) {
+					mask_name = mask_flags[i].mask_name;
+					mask_bitfield = mask_flags[i].mask_bitfield;
+					done = 0;
+					break;
+				}
+			}
+		}
+
+		if (mask_name != NULL) {
+				
+			pos += len;
+			done = 0;
+			switch(add) {
+			case '-':
+				rg &= ~mask_bitfield;
+				break;
+			case '+':
+				rg |= mask_bitfield;
+				break;
+			case '=':
+				rg = mask_bitfield;
+				break;
+			default:
+				rg |= mask_bitfield;
+				break;
+			}
+		}
+	}	
+	// rg = simple_strtoul(buf, NULL, 0);
+	yaffs_traceMask = rg;
+	if (rg & YAFFS_TRACE_ALWAYS) {
+		for (i = 0; mask_flags[i].mask_name != NULL; i++) {
+			char flag;
+			flag = ((rg & mask_flags[i].mask_bitfield) == mask_flags[i].mask_bitfield) ? '+' : '-';
+			printk("%c%s\n", flag, mask_flags[i].mask_name);
+		}
+	}
+	// printk("%08x\n", rg);
+
+	return count;
+}
+
 /* Stuff to handle installation of file systems */
 struct file_system_to_install {
 	struct file_system_type *fst;
@@ -1700,11 +1815,15 @@
 	  ("yaffs " __DATE__ " " __TIME__ " Installing. \n"));
 
 	/* Install the proc_fs entry */
-	my_proc_entry = create_proc_read_entry("yaffs",
+	my_proc_entry = create_proc_entry("yaffs",
 					       S_IRUGO | S_IFREG,
-					       &proc_root,
-					       yaffs_proc_read, NULL);
-	if (!my_proc_entry) {
+					       &proc_root);
+
+	if (my_proc_entry) {
+		my_proc_entry->write_proc = yaffs_proc_write;
+		my_proc_entry->read_proc = yaffs_proc_read;
+		my_proc_entry->data = NULL;
+	} else {
 		return -ENOMEM;
 	}