Merge tag 'trace-seq-file-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into for-next

Pull the beginning of seq_file cleanup from Steven:
  "I'm looking to clean up the seq_file code and to eventually merge the
  trace_seq code with seq_file as well, since they basically do the same thing.

  Part of this process is to remove the return code of seq_printf() and friends
  as they are rather inconsistent. It is better to use the new function
  seq_has_overflowed() if you want to stop processing when the buffer
  is full. Note, if the buffer is full, the seq_file code will throw away
  the contents, allocate a bigger buffer, and then call your code again
  to fill in the data. The only thing that breaking out of the function
  early does is to save a little time which is probably never noticed.

  I started with patches from Joe Perches and modified them as well.
  There's many more places that need to be updated before we can convert
  seq_printf() and friends to return void. But this patch set introduces
  the seq_has_overflowed() and does some initial updates."

6 files changed, 25 insertions, 11 deletions

diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
index 4d0b4d1aa132..d84f8c254a87 100644
--- a/include/linux/debugfs.h
+++ b/include/linux/debugfs.h
@@ -92,8 +92,8 @@ struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
 				     struct dentry *parent,
 				     struct debugfs_regset32 *regset);
 
-int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
-			 int nregs, void __iomem *base, char *prefix);
+void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
+			  int nregs, void __iomem *base, char *prefix);
 
 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
 					struct dentry *parent,
@@ -233,10 +233,9 @@ static inline struct dentry *debugfs_create_regset32(const char *name,
 	return ERR_PTR(-ENODEV);
 }
 
-static inline int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
+static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
 			 int nregs, void __iomem *base, char *prefix)
 {
-	return 0;
 }
 
 static inline bool debugfs_initialized(void)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 1a8bb3c023a1..2beddc284bc2 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1515,7 +1515,7 @@ struct file_operations {
 	int (*setlease)(struct file *, long, struct file_lock **, void **);
 	long (*fallocate)(struct file *file, int mode, loff_t offset,
 			  loff_t len);
-	int (*show_fdinfo)(struct seq_file *m, struct file *f);
+	void (*show_fdinfo)(struct seq_file *m, struct file *f);
 };
 
 struct inode_operations {
diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h
index 52e0097f61f0..cf6a9daaaf6d 100644
--- a/include/linux/seq_file.h
+++ b/include/linux/seq_file.h
@@ -43,6 +43,21 @@ struct seq_operations {
 #define SEQ_SKIP 1
 
 /**
+ * seq_has_overflowed - check if the buffer has overflowed
+ * @m: the seq_file handle
+ *
+ * seq_files have a buffer which may overflow. When this happens a larger
+ * buffer is reallocated and all the data will be printed again.
+ * The overflow state is true when m->count == m->size.
+ *
+ * Returns true if the buffer received more than it can hold.
+ */
+static inline bool seq_has_overflowed(struct seq_file *m)
+{
+	return m->count == m->size;
+}
+
+/**
  * seq_get_buf - get buffer to write arbitrary data to
  * @m: the seq_file handle
  * @bufp: the beginning of the buffer is stored here
diff --git a/include/net/netfilter/nf_conntrack_core.h b/include/net/netfilter/nf_conntrack_core.h
index cc0c18827602..f2f0fa3bb150 100644
--- a/include/net/netfilter/nf_conntrack_core.h
+++ b/include/net/netfilter/nf_conntrack_core.h
@@ -72,7 +72,7 @@ static inline int nf_conntrack_confirm(struct sk_buff *skb)
 	return ret;
 }
 
-int
+void
 print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple,
             const struct nf_conntrack_l3proto *l3proto,
             const struct nf_conntrack_l4proto *proto);
diff --git a/include/net/netfilter/nf_conntrack_l3proto.h b/include/net/netfilter/nf_conntrack_l3proto.h
index adc1fa3dd7ab..cdc920b4c4c2 100644
--- a/include/net/netfilter/nf_conntrack_l3proto.h
+++ b/include/net/netfilter/nf_conntrack_l3proto.h
@@ -38,8 +38,8 @@ struct nf_conntrack_l3proto {
 			     const struct nf_conntrack_tuple *orig);
 
 	/* Print out the per-protocol part of the tuple. */
-	int (*print_tuple)(struct seq_file *s,
-			   const struct nf_conntrack_tuple *);
+	void (*print_tuple)(struct seq_file *s,
+			    const struct nf_conntrack_tuple *);
 
 	/*
 	 * Called before tracking. 
diff --git a/include/net/netfilter/nf_conntrack_l4proto.h b/include/net/netfilter/nf_conntrack_l4proto.h
index 4c8d573830b7..1f7061313d54 100644
--- a/include/net/netfilter/nf_conntrack_l4proto.h
+++ b/include/net/netfilter/nf_conntrack_l4proto.h
@@ -56,11 +56,11 @@ struct nf_conntrack_l4proto {
 		     u_int8_t pf, unsigned int hooknum);
 
 	/* Print out the per-protocol part of the tuple. Return like seq_* */
-	int (*print_tuple)(struct seq_file *s,
-			   const struct nf_conntrack_tuple *);
+	void (*print_tuple)(struct seq_file *s,
+			    const struct nf_conntrack_tuple *);
 
 	/* Print out the private part of the conntrack. */
-	int (*print_conntrack)(struct seq_file *s, struct nf_conn *);
+	void (*print_conntrack)(struct seq_file *s, struct nf_conn *);
 
 	/* Return the array of timeouts for this protocol. */
 	unsigned int *(*get_timeouts)(struct net *net);