tracing: Clean up trace_seq.c

For using trace_seq_*() functions in NMI context, I posted a patch to move
it to the lib/ directory. This caused Andrew Morton to take a look at the code.
He went through and gave a lot of comments about missing kernel doc,
inconsistent types for the save variable, mix match of EXPORT_SYMBOL_GPL()
and EXPORT_SYMBOL() as well as missing EXPORT_SYMBOL*()s. There were
a few comments about the way variables were being compared (int vs uint).

All these were good review comments and should be implemented regardless of
if trace_seq.c should be moved to lib/ or not.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

include/linux/trace_seq.h

@@ -38,14 +38,14 @@ int trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args);
 extern int
 trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary);
 extern int trace_print_seq(struct seq_file *m, struct trace_seq *s);
-extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
-				 size_t cnt);
+extern int trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
+			     int cnt);
 extern int trace_seq_puts(struct trace_seq *s, const char *str);
 extern int trace_seq_putc(struct trace_seq *s, unsigned char c);
-extern int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len);
+extern int trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len);
 extern int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
-				size_t len);
-extern void *trace_seq_reserve(struct trace_seq *s, size_t len);
+				unsigned int len);
+extern void *trace_seq_reserve(struct trace_seq *s, unsigned int len);
 extern int trace_seq_path(struct trace_seq *s, const struct path *path);
 
 extern int trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
@@ -73,8 +73,8 @@ static inline int trace_print_seq(struct seq_file *m, struct trace_seq *s)
 {
 	return 0;
 }
-static inline ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
-				 size_t cnt)
+static inline int trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
+				    int cnt)
 {
 	return 0;
 }
@@ -87,16 +87,16 @@ static inline int trace_seq_putc(struct trace_seq *s, unsigned char c)
 	return 0;
 }
 static inline int
-trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
+trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len)
 {
 	return 0;
 }
 static inline int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
-				       size_t len)
+				       unsigned int len)
 {
 	return 0;
 }
-static inline void *trace_seq_reserve(struct trace_seq *s, size_t len)
+static inline void *trace_seq_reserve(struct trace_seq *s, unsigned int len)
 {
 	return NULL;
 }