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."

Documentation/filesystems/debugfs.txt

@@ -140,7 +140,7 @@ file.
 				     struct dentry *parent,
 				     struct debugfs_regset32 *regset);
 
-    int debugfs_print_regs32(struct seq_file *s, struct debugfs_reg32 *regs,
+    void debugfs_print_regs32(struct seq_file *s, struct debugfs_reg32 *regs,
 			 int nregs, void __iomem *base, char *prefix);
 
 The "base" argument may be 0, but you may want to build the reg32 array

Documentation/filesystems/seq_file.txt

@@ -180,23 +180,19 @@ output must be passed to the seq_file code. Some utility functions have
 been defined which make this task easy.
 
 Most code will simply use seq_printf(), which works pretty much like
-printk(), but which requires the seq_file pointer as an argument. It is
-common to ignore the return value from seq_printf(), but a function
-producing complicated output may want to check that value and quit if
-something non-zero is returned; an error return means that the seq_file
-buffer has been filled and further output will be discarded.
+printk(), but which requires the seq_file pointer as an argument.
 
 For straight character output, the following functions may be used:
 
-	int seq_putc(struct seq_file *m, char c);
-	int seq_puts(struct seq_file *m, const char *s);
-	int seq_escape(struct seq_file *m, const char *s, const char *esc);
+	seq_putc(struct seq_file *m, char c);
+	seq_puts(struct seq_file *m, const char *s);
+	seq_escape(struct seq_file *m, const char *s, const char *esc);
 
 The first two output a single character and a string, just like one would
 expect. seq_escape() is like seq_puts(), except that any character in s
 which is in the string esc will be represented in octal form in the output.
 
-There is also a pair of functions for printing filenames:
+There are also a pair of functions for printing filenames:
 
 	int seq_path(struct seq_file *m, struct path *path, char *esc);
 	int seq_path_root(struct seq_file *m, struct path *path,
@@ -209,6 +205,14 @@ root is desired, it can be used with seq_path_root().  Note that, if it
 turns out that path cannot be reached from root, the value of root will be
 changed in seq_file_root() to a root which *does* work.
 
+A function producing complicated output may want to check
+	bool seq_has_overflowed(struct seq_file *m);
+and avoid further seq_<output> calls if true is returned.
+
+A true return from seq_has_overflowed means that the seq_file buffer will
+be discarded and the seq_show function will attempt to allocate a larger
+buffer and retry printing.
+
 
 Making it all work
 

Documentation/filesystems/vfs.txt

@@ -835,7 +835,7 @@ struct file_operations {
 	ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int);
 	int (*setlease)(struct file *, long arg, struct file_lock **, void **);
 	long (*fallocate)(struct 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);
 };
 
 Again, all methods are called without any locks being held, unless

drivers/net/tun.c

@@ -2209,7 +2209,7 @@ static int tun_chr_close(struct inode *inode, struct file *file)
 }
 
 #ifdef CONFIG_PROC_FS
-static int tun_chr_show_fdinfo(struct seq_file *m, struct file *f)
+static void tun_chr_show_fdinfo(struct seq_file *m, struct file *f)
 {
 	struct tun_struct *tun;
 	struct ifreq ifr;
@@ -2225,7 +2225,7 @@ static int tun_chr_show_fdinfo(struct seq_file *m, struct file *f)
 	if (tun)
 		tun_put(tun);
 
-	return seq_printf(m, "iff:\t%s\n", ifr.ifr_name);
+	seq_printf(m, "iff:\t%s\n", ifr.ifr_name);
 }
 #endif
 

fs/debugfs/file.c

@@ -692,18 +692,19 @@ EXPORT_SYMBOL_GPL(debugfs_create_u32_array);
  * because some peripherals have several blocks of identical registers,
  * for example configuration of dma channels
  */
-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)
 {
-	int i, ret = 0;
+	int i;
 
 	for (i = 0; i < nregs; i++, regs++) {
 		if (prefix)
-			ret += seq_printf(s, "%s", prefix);
-		ret += seq_printf(s, "%s = 0x%08x\n", regs->name,
-				  readl(base + regs->offset));
+			seq_printf(s, "%s", prefix);
+		seq_printf(s, "%s = 0x%08x\n", regs->name,
+			   readl(base + regs->offset));
+		if (seq_has_overflowed(s))
+			break;
 	}
-	return ret;
 }
 EXPORT_SYMBOL_GPL(debugfs_print_regs32);
 

fs/dlm/debug_fs.c

@@ -48,8 +48,8 @@ static char *print_lockmode(int mode)
 	}
 }
 
-static int print_format1_lock(struct seq_file *s, struct dlm_lkb *lkb,
-			      struct dlm_rsb *res)
+static void print_format1_lock(struct seq_file *s, struct dlm_lkb *lkb,
+			       struct dlm_rsb *res)
 {
 	seq_printf(s, "%08x %s", lkb->lkb_id, print_lockmode(lkb->lkb_grmode));
 
@@ -68,21 +68,17 @@ static int print_format1_lock(struct seq_file *s, struct dlm_lkb *lkb,
 	if (lkb->lkb_wait_type)
 		seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
 
-	return seq_puts(s, "\n");
+	seq_puts(s, "\n");
 }
 
-static int print_format1(struct dlm_rsb *res, struct seq_file *s)
+static void print_format1(struct dlm_rsb *res, struct seq_file *s)
 {
 	struct dlm_lkb *lkb;
 	int i, lvblen = res->res_ls->ls_lvblen, recover_list, root_list;
-	int rv;
 
 	lock_rsb(res);
 
-	rv = seq_printf(s, "\nResource %p Name (len=%d) \"",
-			res, res->res_length);
-	if (rv)
-		goto out;
+	seq_printf(s, "\nResource %p Name (len=%d) \"", res, res->res_length);
 
 	for (i = 0; i < res->res_length; i++) {
 		if (isprint(res->res_name[i]))
@@ -92,17 +88,16 @@ static int print_format1(struct dlm_rsb *res, struct seq_file *s)
 	}
 
 	if (res->res_nodeid > 0)
-		rv = seq_printf(s, "\"\nLocal Copy, Master is node %d\n",
-				res->res_nodeid);
+		seq_printf(s, "\"\nLocal Copy, Master is node %d\n",
+			   res->res_nodeid);
 	else if (res->res_nodeid == 0)
-		rv = seq_puts(s, "\"\nMaster Copy\n");
+		seq_puts(s, "\"\nMaster Copy\n");
 	else if (res->res_nodeid == -1)
-		rv = seq_printf(s, "\"\nLooking up master (lkid %x)\n",
-			   	res->res_first_lkid);
+		seq_printf(s, "\"\nLooking up master (lkid %x)\n",
+			   res->res_first_lkid);
 	else
-		rv = seq_printf(s, "\"\nInvalid master %d\n",
-				res->res_nodeid);
-	if (rv)
+		seq_printf(s, "\"\nInvalid master %d\n", res->res_nodeid);
+	if (seq_has_overflowed(s))
 		goto out;
 
 	/* Print the LVB: */
@@ -116,8 +111,8 @@ static int print_format1(struct dlm_rsb *res, struct seq_file *s)
 		}
 		if (rsb_flag(res, RSB_VALNOTVALID))
 			seq_puts(s, " (INVALID)");
-		rv = seq_puts(s, "\n");
-		if (rv)
+		seq_puts(s, "\n");
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
@@ -125,32 +120,30 @@ static int print_format1(struct dlm_rsb *res, struct seq_file *s)
 	recover_list = !list_empty(&res->res_recover_list);
 
 	if (root_list || recover_list) {
-		rv = seq_printf(s, "Recovery: root %d recover %d flags %lx "
-				"count %d\n", root_list, recover_list,
-			   	res->res_flags, res->res_recover_locks_count);
-		if (rv)
-			goto out;
+		seq_printf(s, "Recovery: root %d recover %d flags %lx count %d\n",
+			   root_list, recover_list,
+			   res->res_flags, res->res_recover_locks_count);
 	}
 
 	/* Print the locks attached to this resource */
 	seq_puts(s, "Granted Queue\n");
 	list_for_each_entry(lkb, &res->res_grantqueue, lkb_statequeue) {
-		rv = print_format1_lock(s, lkb, res);
-		if (rv)
+		print_format1_lock(s, lkb, res);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	seq_puts(s, "Conversion Queue\n");
 	list_for_each_entry(lkb, &res->res_convertqueue, lkb_statequeue) {
-		rv = print_format1_lock(s, lkb, res);
-		if (rv)
+		print_format1_lock(s, lkb, res);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	seq_puts(s, "Waiting Queue\n");
 	list_for_each_entry(lkb, &res->res_waitqueue, lkb_statequeue) {
-		rv = print_format1_lock(s, lkb, res);
-		if (rv)
+		print_format1_lock(s, lkb, res);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
@@ -159,23 +152,23 @@ static int print_format1(struct dlm_rsb *res, struct seq_file *s)
 
 	seq_puts(s, "Lookup Queue\n");
 	list_for_each_entry(lkb, &res->res_lookup, lkb_rsb_lookup) {
-		rv = seq_printf(s, "%08x %s", lkb->lkb_id,
-				print_lockmode(lkb->lkb_rqmode));
+		seq_printf(s, "%08x %s",
+			   lkb->lkb_id, print_lockmode(lkb->lkb_rqmode));
 		if (lkb->lkb_wait_type)
 			seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
-		rv = seq_puts(s, "\n");
+		seq_puts(s, "\n");
+		if (seq_has_overflowed(s))
+			goto out;
 	}
  out:
 	unlock_rsb(res);
-	return rv;
 }
 
-static int print_format2_lock(struct seq_file *s, struct dlm_lkb *lkb,
-			      struct dlm_rsb *r)
+static void print_format2_lock(struct seq_file *s, struct dlm_lkb *lkb,
+			       struct dlm_rsb *r)
 {
 	u64 xid = 0;
 	u64 us;
-	int rv;
 
 	if (lkb->lkb_flags & DLM_IFL_USER) {
 		if (lkb->lkb_ua)
@@ -188,103 +181,97 @@ static int print_format2_lock(struct seq_file *s, struct dlm_lkb *lkb,
 	/* id nodeid remid pid xid exflags flags sts grmode rqmode time_us
 	   r_nodeid r_len r_name */
 
-	rv = seq_printf(s, "%x %d %x %u %llu %x %x %d %d %d %llu %u %d \"%s\"\n",
-			lkb->lkb_id,
-			lkb->lkb_nodeid,
-			lkb->lkb_remid,
-			lkb->lkb_ownpid,
-			(unsigned long long)xid,
-			lkb->lkb_exflags,
-			lkb->lkb_flags,
-			lkb->lkb_status,
-			lkb->lkb_grmode,
-			lkb->lkb_rqmode,
-			(unsigned long long)us,
-			r->res_nodeid,
-			r->res_length,
-			r->res_name);
-	return rv;
+	seq_printf(s, "%x %d %x %u %llu %x %x %d %d %d %llu %u %d \"%s\"\n",
+		   lkb->lkb_id,
+		   lkb->lkb_nodeid,
+		   lkb->lkb_remid,
+		   lkb->lkb_ownpid,
+		   (unsigned long long)xid,
+		   lkb->lkb_exflags,
+		   lkb->lkb_flags,
+		   lkb->lkb_status,
+		   lkb->lkb_grmode,
+		   lkb->lkb_rqmode,
+		   (unsigned long long)us,
+		   r->res_nodeid,
+		   r->res_length,
+		   r->res_name);
 }
 
-static int print_format2(struct dlm_rsb *r, struct seq_file *s)
+static void print_format2(struct dlm_rsb *r, struct seq_file *s)
 {
 	struct dlm_lkb *lkb;
-	int rv = 0;
 
 	lock_rsb(r);
 
 	list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
-		rv = print_format2_lock(s, lkb, r);
-		if (rv)
+		print_format2_lock(s, lkb, r);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
-		rv = print_format2_lock(s, lkb, r);
-		if (rv)
+		print_format2_lock(s, lkb, r);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) {
-		rv = print_format2_lock(s, lkb, r);
-		if (rv)
+		print_format2_lock(s, lkb, r);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
  out:
 	unlock_rsb(r);
-	return rv;
 }
 
-static int print_format3_lock(struct seq_file *s, struct dlm_lkb *lkb,
+static void print_format3_lock(struct seq_file *s, struct dlm_lkb *lkb,
 			      int rsb_lookup)
 {
 	u64 xid = 0;
-	int rv;
 
 	if (lkb->lkb_flags & DLM_IFL_USER) {
 		if (lkb->lkb_ua)
 			xid = lkb->lkb_ua->xid;
 	}
 
-	rv = seq_printf(s, "lkb %x %d %x %u %llu %x %x %d %d %d %d %d %d %u %llu %llu\n",
-			lkb->lkb_id,
-			lkb->lkb_nodeid,
-			lkb->lkb_remid,
-			lkb->lkb_ownpid,
-			(unsigned long long)xid,
-			lkb->lkb_exflags,
-			lkb->lkb_flags,
-			lkb->lkb_status,
-			lkb->lkb_grmode,
-			lkb->lkb_rqmode,
-			lkb->lkb_last_bast.mode,
-			rsb_lookup,
-			lkb->lkb_wait_type,
-			lkb->lkb_lvbseq,
-			(unsigned long long)ktime_to_ns(lkb->lkb_timestamp),
-			(unsigned long long)ktime_to_ns(lkb->lkb_last_bast_time));
-	return rv;
+	seq_printf(s, "lkb %x %d %x %u %llu %x %x %d %d %d %d %d %d %u %llu %llu\n",
+		   lkb->lkb_id,
+		   lkb->lkb_nodeid,
+		   lkb->lkb_remid,
+		   lkb->lkb_ownpid,
+		   (unsigned long long)xid,
+		   lkb->lkb_exflags,
+		   lkb->lkb_flags,
+		   lkb->lkb_status,
+		   lkb->lkb_grmode,
+		   lkb->lkb_rqmode,
+		   lkb->lkb_last_bast.mode,
+		   rsb_lookup,
+		   lkb->lkb_wait_type,
+		   lkb->lkb_lvbseq,
+		   (unsigned long long)ktime_to_ns(lkb->lkb_timestamp),
+		   (unsigned long long)ktime_to_ns(lkb->lkb_last_bast_time));
 }
 
-static int print_format3(struct dlm_rsb *r, struct seq_file *s)
+static void print_format3(struct dlm_rsb *r, struct seq_file *s)
 {
 	struct dlm_lkb *lkb;
 	int i, lvblen = r->res_ls->ls_lvblen;
 	int print_name = 1;
-	int rv;
 
 	lock_rsb(r);
 
-	rv = seq_printf(s, "rsb %p %d %x %lx %d %d %u %d ",
-			r,
-			r->res_nodeid,
-			r->res_first_lkid,
-			r->res_flags,
-			!list_empty(&r->res_root_list),
-			!list_empty(&r->res_recover_list),
-			r->res_recover_locks_count,
-			r->res_length);
-	if (rv)
+	seq_printf(s, "rsb %p %d %x %lx %d %d %u %d ",
+		   r,
+		   r->res_nodeid,
+		   r->res_first_lkid,
+		   r->res_flags,
+		   !list_empty(&r->res_root_list),
+		   !list_empty(&r->res_recover_list),
+		   r->res_recover_locks_count,
+		   r->res_length);
+	if (seq_has_overflowed(s))
 		goto out;
 
 	for (i = 0; i < r->res_length; i++) {
@@ -292,7 +279,7 @@ static int print_format3(struct dlm_rsb *r, struct seq_file *s)
 			print_name = 0;
 	}
 
-	seq_printf(s, "%s", print_name ? "str " : "hex");
+	seq_puts(s, print_name ? "str " : "hex");
 
 	for (i = 0; i < r->res_length; i++) {
 		if (print_name)
@@ -300,8 +287,8 @@ static int print_format3(struct dlm_rsb *r, struct seq_file *s)
 		else
 			seq_printf(s, " %02x", (unsigned char)r->res_name[i]);
 	}
-	rv = seq_puts(s, "\n");
-	if (rv)
+	seq_puts(s, "\n");
+	if (seq_has_overflowed(s))
 		goto out;
 
 	if (!r->res_lvbptr)
@@ -311,65 +298,62 @@ static int print_format3(struct dlm_rsb *r, struct seq_file *s)
 
 	for (i = 0; i < lvblen; i++)
 		seq_printf(s, " %02x", (unsigned char)r->res_lvbptr[i]);
-	rv = seq_puts(s, "\n");
-	if (rv)
+	seq_puts(s, "\n");
+	if (seq_has_overflowed(s))
 		goto out;
 
  do_locks:
 	list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
-		rv = print_format3_lock(s, lkb, 0);
-		if (rv)
+		print_format3_lock(s, lkb, 0);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
-		rv = print_format3_lock(s, lkb, 0);
-		if (rv)
+		print_format3_lock(s, lkb, 0);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) {
-		rv = print_format3_lock(s, lkb, 0);
-		if (rv)
+		print_format3_lock(s, lkb, 0);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup) {
-		rv = print_format3_lock(s, lkb, 1);
-		if (rv)
+		print_format3_lock(s, lkb, 1);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
  out:
 	unlock_rsb(r);
-	return rv;
 }
 
-static int print_format4(struct dlm_rsb *r, struct seq_file *s)
+static void print_format4(struct dlm_rsb *r, struct seq_file *s)
 {
 	int our_nodeid = dlm_our_nodeid();
 	int print_name = 1;
-	int i, rv;
+	int i;
 
 	lock_rsb(r);
 
-	rv = seq_printf(s, "rsb %p %d %d %d %d %lu %lx %d ",
-			r,
-			r->res_nodeid,
-			r->res_master_nodeid,
-			r->res_dir_nodeid,
-			our_nodeid,
-			r->res_toss_time,
-			r->res_flags,
-			r->res_length);
-	if (rv)
-		goto out;
+	seq_printf(s, "rsb %p %d %d %d %d %lu %lx %d ",
+		   r,
+		   r->res_nodeid,
+		   r->res_master_nodeid,
+		   r->res_dir_nodeid,
+		   our_nodeid,
+		   r->res_toss_time,
+		   r->res_flags,
+		   r->res_length);
 
 	for (i = 0; i < r->res_length; i++) {
 		if (!isascii(r->res_name[i]) || !isprint(r->res_name[i]))
 			print_name = 0;
 	}
 
-	seq_printf(s, "%s", print_name ? "str " : "hex");
+	seq_puts(s, print_name ? "str " : "hex");
 
 	for (i = 0; i < r->res_length; i++) {
 		if (print_name)
@@ -377,10 +361,9 @@ static int print_format4(struct dlm_rsb *r, struct seq_file *s)
 		else
 			seq_printf(s, " %02x", (unsigned char)r->res_name[i]);
 	}
-	rv = seq_puts(s, "\n");
- out:
+	seq_puts(s, "\n");
+
 	unlock_rsb(r);
-	return rv;
 }
 
 struct rsbtbl_iter {
@@ -390,47 +373,45 @@ struct rsbtbl_iter {
 	int header;
 };
 
-/* seq_printf returns -1 if the buffer is full, and 0 otherwise.
-   If the buffer is full, seq_printf can be called again, but it
-   does nothing and just returns -1.  So, the these printing routines
-   periodically check the return value to avoid wasting too much time
-   trying to print to a full buffer. */
+/*
+ * If the buffer is full, seq_printf can be called again, but it
+ * does nothing.  So, the these printing routines periodically check
+ * seq_has_overflowed to avoid wasting too much time trying to print to
+ * a full buffer.
+ */
 
 static int table_seq_show(struct seq_file *seq, void *iter_ptr)
 {
 	struct rsbtbl_iter *ri = iter_ptr;
-	int rv = 0;
 
 	switch (ri->format) {
 	case 1:
-		rv = print_format1(ri->rsb, seq);
+		print_format1(ri->rsb, seq);
 		break;
 	case 2:
 		if (ri->header) {
-			seq_printf(seq, "id nodeid remid pid xid exflags "
-					"flags sts grmode rqmode time_ms "
-					"r_nodeid r_len r_name\n");
+			seq_puts(seq, "id nodeid remid pid xid exflags flags sts grmode rqmode time_ms r_nodeid r_len r_name\n");
 			ri->header = 0;
 		}
-		rv = print_format2(ri->rsb, seq);
+		print_format2(ri->rsb, seq);
 		break;
 	case 3:
 		if (ri->header) {
-			seq_printf(seq, "version rsb 1.1 lvb 1.1 lkb 1.1\n");
+			seq_puts(seq, "version rsb 1.1 lvb 1.1 lkb 1.1\n");
 			ri->header = 0;
 		}
-		rv = print_format3(ri->rsb, seq);
+		print_format3(ri->rsb, seq);
 		break;
 	case 4:
 		if (ri->header) {
-			seq_printf(seq, "version 4 rsb 2\n");
+			seq_puts(seq, "version 4 rsb 2\n");
 			ri->header = 0;
 		}
-		rv = print_format4(ri->rsb, seq);
+		print_format4(ri->rsb, seq);
 		break;
 	}
 
-	return rv;
+	return 0;
 }
 
 static const struct seq_operations format1_seq_ops;

fs/eventfd.c

@@ -287,17 +287,14 @@ static ssize_t eventfd_write(struct file *file, const char __user *buf, size_t c
 }
 
 #ifdef CONFIG_PROC_FS
-static int eventfd_show_fdinfo(struct seq_file *m, struct file *f)
+static void eventfd_show_fdinfo(struct seq_file *m, struct file *f)
 {
 	struct eventfd_ctx *ctx = f->private_data;
-	int ret;
 
 	spin_lock_irq(&ctx->wqh.lock);
-	ret = seq_printf(m, "eventfd-count: %16llx\n",
-			 (unsigned long long)ctx->count);
+	seq_printf(m, "eventfd-count: %16llx\n",
+		   (unsigned long long)ctx->count);
 	spin_unlock_irq(&ctx->wqh.lock);
-
-	return ret;
 }
 #endif
 

fs/eventpoll.c

@@ -870,25 +870,22 @@ static unsigned int ep_eventpoll_poll(struct file *file, poll_table *wait)
 }
 
 #ifdef CONFIG_PROC_FS
-static int ep_show_fdinfo(struct seq_file *m, struct file *f)
+static void ep_show_fdinfo(struct seq_file *m, struct file *f)
 {
 	struct eventpoll *ep = f->private_data;
 	struct rb_node *rbp;
-	int ret = 0;
 
 	mutex_lock(&ep->mtx);
 	for (rbp = rb_first(&ep->rbr); rbp; rbp = rb_next(rbp)) {
 		struct epitem *epi = rb_entry(rbp, struct epitem, rbn);
 
-		ret = seq_printf(m, "tfd: %8d events: %8x data: %16llx\n",
-				 epi->ffd.fd, epi->event.events,
-				 (long long)epi->event.data);
-		if (ret)
+		seq_printf(m, "tfd: %8d events: %8x data: %16llx\n",
+			   epi->ffd.fd, epi->event.events,
+			   (long long)epi->event.data);
+		if (seq_has_overflowed(m))
 			break;
 	}
 	mutex_unlock(&ep->mtx);
-
-	return ret;
 }
 #endif
 

fs/notify/fdinfo.c

@@ -20,25 +20,24 @@
 
 #if defined(CONFIG_INOTIFY_USER) || defined(CONFIG_FANOTIFY)
 
-static int show_fdinfo(struct seq_file *m, struct file *f,
-		       int (*show)(struct seq_file *m, struct fsnotify_mark *mark))
+static void show_fdinfo(struct seq_file *m, struct file *f,
+			void (*show)(struct seq_file *m,
+				     struct fsnotify_mark *mark))
 {
 	struct fsnotify_group *group = f->private_data;
 	struct fsnotify_mark *mark;
-	int ret = 0;
 
 	mutex_lock(&group->mark_mutex);
 	list_for_each_entry(mark, &group->marks_list, g_list) {
-		ret = show(m, mark);
-		if (ret)
+		show(m, mark);
+		if (seq_has_overflowed(m))
 			break;
 	}
 	mutex_unlock(&group->mark_mutex);
-	return ret;
 }
 
 #if defined(CONFIG_EXPORTFS)
-static int show_mark_fhandle(struct seq_file *m, struct inode *inode)
+static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
 {
 	struct {
 		struct file_handle handle;
@@ -52,71 +51,62 @@ static int show_mark_fhandle(struct seq_file *m, struct inode *inode)
 	ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, 0);
 	if ((ret == FILEID_INVALID) || (ret < 0)) {
 		WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret);
-		return 0;
+		return;
 	}
 
 	f.handle.handle_type = ret;
 	f.handle.handle_bytes = size * sizeof(u32);
 
-	ret = seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
-			 f.handle.handle_bytes, f.handle.handle_type);
+	seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
+		   f.handle.handle_bytes, f.handle.handle_type);
 
 	for (i = 0; i < f.handle.handle_bytes; i++)
-		ret |= seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
-
-	return ret;
+		seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
 }
 #else
-static int show_mark_fhandle(struct seq_file *m, struct inode *inode)
+static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
 {
-	return 0;
 }
 #endif
 
 #ifdef CONFIG_INOTIFY_USER
 
-static int inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
+static void inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
 {
 	struct inotify_inode_mark *inode_mark;
 	struct inode *inode;
-	int ret = 0;
 
 	if (!(mark->flags & (FSNOTIFY_MARK_FLAG_ALIVE | FSNOTIFY_MARK_FLAG_INODE)))
-		return 0;
+		return;
 
 	inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark);
 	inode = igrab(mark->i.inode);
 	if (inode) {
-		ret = seq_printf(m, "inotify wd:%x ino:%lx sdev:%x "
-				 "mask:%x ignored_mask:%x ",
-				 inode_mark->wd, inode->i_ino,
-				 inode->i_sb->s_dev,
-				 mark->mask, mark->ignored_mask);
-		ret |= show_mark_fhandle(m, inode);
-		ret |= seq_putc(m, '\n');
+		seq_printf(m, "inotify wd:%x ino:%lx sdev:%x mask:%x ignored_mask:%x ",
+			   inode_mark->wd, inode->i_ino, inode->i_sb->s_dev,
+			   mark->mask, mark->ignored_mask);
+		show_mark_fhandle(m, inode);
+		seq_putc(m, '\n');
 		iput(inode);
 	}
-
-	return ret;
 }
 
-int inotify_show_fdinfo(struct seq_file *m, struct file *f)
+void inotify_show_fdinfo(struct seq_file *m, struct file *f)
 {
-	return show_fdinfo(m, f, inotify_fdinfo);
+	show_fdinfo(m, f, inotify_fdinfo);
 }
 
 #endif /* CONFIG_INOTIFY_USER */
 
 #ifdef CONFIG_FANOTIFY
 
-static int fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
+static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
 {
 	unsigned int mflags = 0;
 	struct inode *inode;
-	int ret = 0;
 
 	if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE))
-		return 0;
+		return;
 
 	if (mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)
 		mflags |= FAN_MARK_IGNORED_SURV_MODIFY;
@@ -124,26 +114,22 @@ static int fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
 	if (mark->flags & FSNOTIFY_MARK_FLAG_INODE) {
 		inode = igrab(mark->i.inode);
 		if (!inode)
-			goto out;
-		ret = seq_printf(m, "fanotify ino:%lx sdev:%x "
-				 "mflags:%x mask:%x ignored_mask:%x ",
-				 inode->i_ino, inode->i_sb->s_dev,
-				 mflags, mark->mask, mark->ignored_mask);
-		ret |= show_mark_fhandle(m, inode);
-		ret |= seq_putc(m, '\n');
+			return;
+		seq_printf(m, "fanotify ino:%lx sdev:%x mflags:%x mask:%x ignored_mask:%x ",
+			   inode->i_ino, inode->i_sb->s_dev,
+			   mflags, mark->mask, mark->ignored_mask);
+		show_mark_fhandle(m, inode);
+		seq_putc(m, '\n');
 		iput(inode);
 	} else if (mark->flags & FSNOTIFY_MARK_FLAG_VFSMOUNT) {
 		struct mount *mnt = real_mount(mark->m.mnt);
 
-		ret = seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x "
-				 "ignored_mask:%x\n", mnt->mnt_id, mflags,
-				 mark->mask, mark->ignored_mask);
+		seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n",
+			   mnt->mnt_id, mflags, mark->mask, mark->ignored_mask);
 	}
-out:
-	return ret;
 }
 
-int fanotify_show_fdinfo(struct seq_file *m, struct file *f)
+void fanotify_show_fdinfo(struct seq_file *m, struct file *f)
 {
 	struct fsnotify_group *group = f->private_data;
 	unsigned int flags = 0;
@@ -169,7 +155,7 @@ int fanotify_show_fdinfo(struct seq_file *m, struct file *f)
 	seq_printf(m, "fanotify flags:%x event-flags:%x\n",
 		   flags, group->fanotify_data.f_flags);
 
-	return show_fdinfo(m, f, fanotify_fdinfo);
+	show_fdinfo(m, f, fanotify_fdinfo);
 }
 
 #endif /* CONFIG_FANOTIFY */

fs/notify/fdinfo.h

@@ -10,11 +10,11 @@ struct file;
 #ifdef CONFIG_PROC_FS
 
 #ifdef CONFIG_INOTIFY_USER
-extern int inotify_show_fdinfo(struct seq_file *m, struct file *f);
+void inotify_show_fdinfo(struct seq_file *m, struct file *f);
 #endif
 
 #ifdef CONFIG_FANOTIFY
-extern int fanotify_show_fdinfo(struct seq_file *m, struct file *f);
+void fanotify_show_fdinfo(struct seq_file *m, struct file *f);
 #endif
 
 #else /* CONFIG_PROC_FS */

fs/proc/fd.c

@@ -53,7 +53,8 @@ static int seq_show(struct seq_file *m, void *v)
 			   (long long)file->f_pos, f_flags,
 			   real_mount(file->f_path.mnt)->mnt_id);
 		if (file->f_op->show_fdinfo)
-			ret = file->f_op->show_fdinfo(m, file);
+			file->f_op->show_fdinfo(m, file);
+		ret = seq_has_overflowed(m);
 		fput(file);
 	}
 

fs/seq_file.c

@@ -16,17 +16,6 @@
 #include <asm/uaccess.h>
 #include <asm/page.h>
 
-
-/*
- * seq_files have a buffer which can 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.
- */
-static bool seq_overflow(struct seq_file *m)
-{
-	return m->count == m->size;
-}
-
 static void seq_set_overflow(struct seq_file *m)
 {
 	m->count = m->size;
@@ -124,7 +113,7 @@ static int traverse(struct seq_file *m, loff_t offset)
 			error = 0;
 			m->count = 0;
 		}
-		if (seq_overflow(m))
+		if (seq_has_overflowed(m))
 			goto Eoverflow;
 		if (pos + m->count > offset) {
 			m->from = offset - pos;
@@ -267,7 +256,7 @@ Fill:
 			break;
 		}
 		err = m->op->show(m, p);
-		if (seq_overflow(m) || err) {
+		if (seq_has_overflowed(m) || err) {
 			m->count = offs;
 			if (likely(err <= 0))
 				break;

fs/signalfd.c

@@ -230,7 +230,7 @@ static ssize_t signalfd_read(struct file *file, char __user *buf, size_t count,
 }
 
 #ifdef CONFIG_PROC_FS
-static int signalfd_show_fdinfo(struct seq_file *m, struct file *f)
+static void signalfd_show_fdinfo(struct seq_file *m, struct file *f)
 {
 	struct signalfd_ctx *ctx = f->private_data;
 	sigset_t sigmask;
@@ -238,8 +238,6 @@ static int signalfd_show_fdinfo(struct seq_file *m, struct file *f)
 	sigmask = ctx->sigmask;
 	signotset(&sigmask);
 	render_sigset_t(m, "sigmask:\t", &sigmask);
-
-	return 0;
 }
 #endif
 

fs/timerfd.c

@@ -288,7 +288,7 @@ static ssize_t timerfd_read(struct file *file, char __user *buf, size_t count,
 }
 
 #ifdef CONFIG_PROC_FS
-static int timerfd_show(struct seq_file *m, struct file *file)
+static void timerfd_show(struct seq_file *m, struct file *file)
 {
 	struct timerfd_ctx *ctx = file->private_data;
 	struct itimerspec t;
@@ -298,18 +298,19 @@ static int timerfd_show(struct seq_file *m, struct file *file)
 	t.it_interval = ktime_to_timespec(ctx->tintv);
 	spin_unlock_irq(&ctx->wqh.lock);
 
-	return seq_printf(m,
-			  "clockid: %d\n"
-			  "ticks: %llu\n"
-			  "settime flags: 0%o\n"
-			  "it_value: (%llu, %llu)\n"
-			  "it_interval: (%llu, %llu)\n",
-			  ctx->clockid, (unsigned long long)ctx->ticks,
-			  ctx->settime_flags,
-			  (unsigned long long)t.it_value.tv_sec,
-			  (unsigned long long)t.it_value.tv_nsec,
-			  (unsigned long long)t.it_interval.tv_sec,
-			  (unsigned long long)t.it_interval.tv_nsec);
+	seq_printf(m,
+		   "clockid: %d\n"
+		   "ticks: %llu\n"
+		   "settime flags: 0%o\n"
+		   "it_value: (%llu, %llu)\n"
+		   "it_interval: (%llu, %llu)\n",
+		   ctx->clockid,
+		   (unsigned long long)ctx->ticks,
+		   ctx->settime_flags,
+		   (unsigned long long)t.it_value.tv_sec,
+		   (unsigned long long)t.it_value.tv_nsec,
+		   (unsigned long long)t.it_interval.tv_sec,
+		   (unsigned long long)t.it_interval.tv_nsec);
 }
 #else
 #define timerfd_show NULL

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)

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 {

include/linux/seq_file.h

@@ -42,6 +42,21 @@ 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

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);

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. 

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);

net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c

@@ -56,11 +56,11 @@ static bool ipv4_invert_tuple(struct nf_conntrack_tuple *tuple,
 	return true;
 }
 
-static int ipv4_print_tuple(struct seq_file *s,
+static void ipv4_print_tuple(struct seq_file *s,
 			    const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "src=%pI4 dst=%pI4 ",
-			  &tuple->src.u3.ip, &tuple->dst.u3.ip);
+	seq_printf(s, "src=%pI4 dst=%pI4 ",
+		   &tuple->src.u3.ip, &tuple->dst.u3.ip);
 }
 
 static int ipv4_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,

net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c

@@ -94,7 +94,7 @@ static void ct_seq_stop(struct seq_file *s, void *v)
 }
 
 #ifdef CONFIG_NF_CONNTRACK_SECMARK
-static int ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
+static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 {
 	int ret;
 	u32 len;
@@ -102,17 +102,15 @@ static int ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 
 	ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
 	if (ret)
-		return 0;
+		return;
 
-	ret = seq_printf(s, "secctx=%s ", secctx);
+	seq_printf(s, "secctx=%s ", secctx);
 
 	security_release_secctx(secctx, len);
-	return ret;
 }
 #else
-static inline int ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
+static inline void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 {
-	return 0;
 }
 #endif
 
@@ -141,47 +139,52 @@ static int ct_seq_show(struct seq_file *s, void *v)
 	NF_CT_ASSERT(l4proto);
 
 	ret = -ENOSPC;
-	if (seq_printf(s, "%-8s %u %ld ",
-		      l4proto->name, nf_ct_protonum(ct),
-		      timer_pending(&ct->timeout)
-		      ? (long)(ct->timeout.expires - jiffies)/HZ : 0) != 0)
-		goto release;
+	seq_printf(s, "%-8s %u %ld ",
+		   l4proto->name, nf_ct_protonum(ct),
+		   timer_pending(&ct->timeout)
+		   ? (long)(ct->timeout.expires - jiffies)/HZ : 0);
+
+	if (l4proto->print_conntrack)
+		l4proto->print_conntrack(s, ct);
 
-	if (l4proto->print_conntrack && l4proto->print_conntrack(s, ct))
+	if (seq_has_overflowed(s))
 		goto release;
 
-	if (print_tuple(s, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
-			l3proto, l4proto))
+	print_tuple(s, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
+		    l3proto, l4proto);
+
+	if (seq_has_overflowed(s))
 		goto release;
 
 	if (seq_print_acct(s, ct, IP_CT_DIR_ORIGINAL))
 		goto release;
 
 	if (!(test_bit(IPS_SEEN_REPLY_BIT, &ct->status)))
-		if (seq_printf(s, "[UNREPLIED] "))
-			goto release;
+		seq_printf(s, "[UNREPLIED] ");
 
-	if (print_tuple(s, &ct->tuplehash[IP_CT_DIR_REPLY].tuple,
-			l3proto, l4proto))
+	print_tuple(s, &ct->tuplehash[IP_CT_DIR_REPLY].tuple,
+		    l3proto, l4proto);
+
+	if (seq_has_overflowed(s))
 		goto release;
 
 	if (seq_print_acct(s, ct, IP_CT_DIR_REPLY))
 		goto release;
 
 	if (test_bit(IPS_ASSURED_BIT, &ct->status))
-		if (seq_printf(s, "[ASSURED] "))
-			goto release;
+		seq_printf(s, "[ASSURED] ");
 
 #ifdef CONFIG_NF_CONNTRACK_MARK
-	if (seq_printf(s, "mark=%u ", ct->mark))
-		goto release;
+	seq_printf(s, "mark=%u ", ct->mark);
 #endif
 
-	if (ct_show_secctx(s, ct))
-		goto release;
+	ct_show_secctx(s, ct);
 
-	if (seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use)))
+	seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use));
+
+	if (seq_has_overflowed(s))
 		goto release;
+
 	ret = 0;
 release:
 	nf_ct_put(ct);

net/ipv4/netfilter/nf_conntrack_proto_icmp.c

@@ -72,13 +72,13 @@ static bool icmp_invert_tuple(struct nf_conntrack_tuple *tuple,
 }
 
 /* Print out the per-protocol part of the tuple. */
-static int icmp_print_tuple(struct seq_file *s,
+static void icmp_print_tuple(struct seq_file *s,
 			    const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "type=%u code=%u id=%u ",
-			  tuple->dst.u.icmp.type,
-			  tuple->dst.u.icmp.code,
-			  ntohs(tuple->src.u.icmp.id));
+	seq_printf(s, "type=%u code=%u id=%u ",
+		   tuple->dst.u.icmp.type,
+		   tuple->dst.u.icmp.code,
+		   ntohs(tuple->src.u.icmp.id));
 }
 
 static unsigned int *icmp_get_timeouts(struct net *net)

net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c

@@ -60,11 +60,11 @@ static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
 	return true;
 }
 
-static int ipv6_print_tuple(struct seq_file *s,
+static void ipv6_print_tuple(struct seq_file *s,
 			    const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "src=%pI6 dst=%pI6 ",
-			  tuple->src.u3.ip6, tuple->dst.u3.ip6);
+	seq_printf(s, "src=%pI6 dst=%pI6 ",
+		   tuple->src.u3.ip6, tuple->dst.u3.ip6);
 }
 
 static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,

net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c

@@ -84,13 +84,13 @@ static bool icmpv6_invert_tuple(struct nf_conntrack_tuple *tuple,
 }
 
 /* Print out the per-protocol part of the tuple. */
-static int icmpv6_print_tuple(struct seq_file *s,
+static void icmpv6_print_tuple(struct seq_file *s,
 			      const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "type=%u code=%u id=%u ",
-			  tuple->dst.u.icmp.type,
-			  tuple->dst.u.icmp.code,
-			  ntohs(tuple->src.u.icmp.id));
+	seq_printf(s, "type=%u code=%u id=%u ",
+		   tuple->dst.u.icmp.type,
+		   tuple->dst.u.icmp.code,
+		   ntohs(tuple->src.u.icmp.id));
 }
 
 static unsigned int *icmpv6_get_timeouts(struct net *net)

net/netfilter/nf_conntrack_l3proto_generic.c

@@ -49,10 +49,9 @@ static bool generic_invert_tuple(struct nf_conntrack_tuple *tuple,
 	return true;
 }
 
-static int generic_print_tuple(struct seq_file *s,
-			    const struct nf_conntrack_tuple *tuple)
+static void generic_print_tuple(struct seq_file *s,
+				const struct nf_conntrack_tuple *tuple)
 {
-	return 0;
 }
 
 static int generic_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,

net/netfilter/nf_conntrack_proto_dccp.c

@@ -618,17 +618,17 @@ out_invalid:
 	return -NF_ACCEPT;
 }
 
-static int dccp_print_tuple(struct seq_file *s,
-			    const struct nf_conntrack_tuple *tuple)
+static void dccp_print_tuple(struct seq_file *s,
+			     const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "sport=%hu dport=%hu ",
-			  ntohs(tuple->src.u.dccp.port),
-			  ntohs(tuple->dst.u.dccp.port));
+	seq_printf(s, "sport=%hu dport=%hu ",
+		   ntohs(tuple->src.u.dccp.port),
+		   ntohs(tuple->dst.u.dccp.port));
 }
 
-static int dccp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
+static void dccp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
 {
-	return seq_printf(s, "%s ", dccp_state_names[ct->proto.dccp.state]);
+	seq_printf(s, "%s ", dccp_state_names[ct->proto.dccp.state]);
 }
 
 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)

net/netfilter/nf_conntrack_proto_generic.c

@@ -63,10 +63,9 @@ static bool generic_invert_tuple(struct nf_conntrack_tuple *tuple,
 }
 
 /* Print out the per-protocol part of the tuple. */
-static int generic_print_tuple(struct seq_file *s,
-			       const struct nf_conntrack_tuple *tuple)
+static void generic_print_tuple(struct seq_file *s,
+				const struct nf_conntrack_tuple *tuple)
 {
-	return 0;
 }
 
 static unsigned int *generic_get_timeouts(struct net *net)

net/netfilter/nf_conntrack_proto_gre.c

@@ -226,20 +226,20 @@ static bool gre_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
 }
 
 /* print gre part of tuple */
-static int gre_print_tuple(struct seq_file *s,
-			   const struct nf_conntrack_tuple *tuple)
+static void gre_print_tuple(struct seq_file *s,
+			    const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "srckey=0x%x dstkey=0x%x ",
-			  ntohs(tuple->src.u.gre.key),
-			  ntohs(tuple->dst.u.gre.key));
+	seq_printf(s, "srckey=0x%x dstkey=0x%x ",
+		   ntohs(tuple->src.u.gre.key),
+		   ntohs(tuple->dst.u.gre.key));
 }
 
 /* print private data for conntrack */
-static int gre_print_conntrack(struct seq_file *s, struct nf_conn *ct)
+static void gre_print_conntrack(struct seq_file *s, struct nf_conn *ct)
 {
-	return seq_printf(s, "timeout=%u, stream_timeout=%u ",
-			  (ct->proto.gre.timeout / HZ),
-			  (ct->proto.gre.stream_timeout / HZ));
+	seq_printf(s, "timeout=%u, stream_timeout=%u ",
+		   (ct->proto.gre.timeout / HZ),
+		   (ct->proto.gre.stream_timeout / HZ));
 }
 
 static unsigned int *gre_get_timeouts(struct net *net)

net/netfilter/nf_conntrack_proto_sctp.c

@@ -166,16 +166,16 @@ static bool sctp_invert_tuple(struct nf_conntrack_tuple *tuple,
 }
 
 /* Print out the per-protocol part of the tuple. */
-static int sctp_print_tuple(struct seq_file *s,
-			    const struct nf_conntrack_tuple *tuple)
+static void sctp_print_tuple(struct seq_file *s,
+			     const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "sport=%hu dport=%hu ",
-			  ntohs(tuple->src.u.sctp.port),
-			  ntohs(tuple->dst.u.sctp.port));
+	seq_printf(s, "sport=%hu dport=%hu ",
+		   ntohs(tuple->src.u.sctp.port),
+		   ntohs(tuple->dst.u.sctp.port));
 }
 
 /* Print out the private part of the conntrack. */
-static int sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
+static void sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
 {
 	enum sctp_conntrack state;
 
@@ -183,7 +183,7 @@ static int sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
 	state = ct->proto.sctp.state;
 	spin_unlock_bh(&ct->lock);
 
-	return seq_printf(s, "%s ", sctp_conntrack_names[state]);
+	seq_printf(s, "%s ", sctp_conntrack_names[state]);
 }
 
 #define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count)	\

net/netfilter/nf_conntrack_proto_tcp.c

@@ -302,16 +302,16 @@ static bool tcp_invert_tuple(struct nf_conntrack_tuple *tuple,
 }
 
 /* Print out the per-protocol part of the tuple. */
-static int tcp_print_tuple(struct seq_file *s,
-			   const struct nf_conntrack_tuple *tuple)
+static void tcp_print_tuple(struct seq_file *s,
+			    const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "sport=%hu dport=%hu ",
-			  ntohs(tuple->src.u.tcp.port),
-			  ntohs(tuple->dst.u.tcp.port));
+	seq_printf(s, "sport=%hu dport=%hu ",
+		   ntohs(tuple->src.u.tcp.port),
+		   ntohs(tuple->dst.u.tcp.port));
 }
 
 /* Print out the private part of the conntrack. */
-static int tcp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
+static void tcp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
 {
 	enum tcp_conntrack state;
 
@@ -319,7 +319,7 @@ static int tcp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
 	state = ct->proto.tcp.state;
 	spin_unlock_bh(&ct->lock);
 
-	return seq_printf(s, "%s ", tcp_conntrack_names[state]);
+	seq_printf(s, "%s ", tcp_conntrack_names[state]);
 }
 
 static unsigned int get_conntrack_index(const struct tcphdr *tcph)

net/netfilter/nf_conntrack_proto_udp.c

@@ -63,12 +63,12 @@ static bool udp_invert_tuple(struct nf_conntrack_tuple *tuple,
 }
 
 /* Print out the per-protocol part of the tuple. */
-static int udp_print_tuple(struct seq_file *s,
-			   const struct nf_conntrack_tuple *tuple)
+static void udp_print_tuple(struct seq_file *s,
+			    const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "sport=%hu dport=%hu ",
-			  ntohs(tuple->src.u.udp.port),
-			  ntohs(tuple->dst.u.udp.port));
+	seq_printf(s, "sport=%hu dport=%hu ",
+		   ntohs(tuple->src.u.udp.port),
+		   ntohs(tuple->dst.u.udp.port));
 }
 
 static unsigned int *udp_get_timeouts(struct net *net)

net/netfilter/nf_conntrack_proto_udplite.c

@@ -71,12 +71,12 @@ static bool udplite_invert_tuple(struct nf_conntrack_tuple *tuple,
 }
 
 /* Print out the per-protocol part of the tuple. */
-static int udplite_print_tuple(struct seq_file *s,
-			       const struct nf_conntrack_tuple *tuple)
+static void udplite_print_tuple(struct seq_file *s,
+				const struct nf_conntrack_tuple *tuple)
 {
-	return seq_printf(s, "sport=%hu dport=%hu ",
-			  ntohs(tuple->src.u.udp.port),
-			  ntohs(tuple->dst.u.udp.port));
+	seq_printf(s, "sport=%hu dport=%hu ",
+		   ntohs(tuple->src.u.udp.port),
+		   ntohs(tuple->dst.u.udp.port));
 }
 
 static unsigned int *udplite_get_timeouts(struct net *net)

net/netfilter/nf_conntrack_standalone.c

@@ -36,12 +36,13 @@
 MODULE_LICENSE("GPL");
 
 #ifdef CONFIG_NF_CONNTRACK_PROCFS
-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 *l4proto)
 {
-	return l3proto->print_tuple(s, tuple) || l4proto->print_tuple(s, tuple);
+	l3proto->print_tuple(s, tuple);
+	l4proto->print_tuple(s, tuple);
 }
 EXPORT_SYMBOL_GPL(print_tuple);
 
@@ -119,7 +120,7 @@ static void ct_seq_stop(struct seq_file *s, void *v)
 }
 
 #ifdef CONFIG_NF_CONNTRACK_SECMARK
-static int ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
+static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 {
 	int ret;
 	u32 len;
@@ -127,22 +128,20 @@ static int ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 
 	ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
 	if (ret)
-		return 0;
+		return;
 
-	ret = seq_printf(s, "secctx=%s ", secctx);
+	seq_printf(s, "secctx=%s ", secctx);
 
 	security_release_secctx(secctx, len);
-	return ret;
 }
 #else
-static inline int ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
+static inline void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 {
-	return 0;
 }
 #endif
 
 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
-static int ct_show_delta_time(struct seq_file *s, const struct nf_conn *ct)
+static void ct_show_delta_time(struct seq_file *s, const struct nf_conn *ct)
 {
 	struct ct_iter_state *st = s->private;
 	struct nf_conn_tstamp *tstamp;
@@ -156,16 +155,15 @@ static int ct_show_delta_time(struct seq_file *s, const struct nf_conn *ct)
 		else
 			delta_time = 0;
 
-		return seq_printf(s, "delta-time=%llu ",
-				  (unsigned long long)delta_time);
+		seq_printf(s, "delta-time=%llu ",
+			   (unsigned long long)delta_time);
 	}
-	return 0;
+	return;
 }
 #else
-static inline int
+static inline void
 ct_show_delta_time(struct seq_file *s, const struct nf_conn *ct)
 {
-	return 0;
 }
 #endif
 
@@ -192,55 +190,54 @@ static int ct_seq_show(struct seq_file *s, void *v)
 	NF_CT_ASSERT(l4proto);
 
 	ret = -ENOSPC;
-	if (seq_printf(s, "%-8s %u %-8s %u %ld ",
-		       l3proto->name, nf_ct_l3num(ct),
-		       l4proto->name, nf_ct_protonum(ct),
-		       timer_pending(&ct->timeout)
-		       ? (long)(ct->timeout.expires - jiffies)/HZ : 0) != 0)
-		goto release;
+	seq_printf(s, "%-8s %u %-8s %u %ld ",
+		   l3proto->name, nf_ct_l3num(ct),
+		   l4proto->name, nf_ct_protonum(ct),
+		   timer_pending(&ct->timeout)
+		   ? (long)(ct->timeout.expires - jiffies)/HZ : 0);
 
-	if (l4proto->print_conntrack && l4proto->print_conntrack(s, ct))
-		goto release;
+	if (l4proto->print_conntrack)
+		l4proto->print_conntrack(s, ct);
+
+	print_tuple(s, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
+		    l3proto, l4proto);
 
-	if (print_tuple(s, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
-			l3proto, l4proto))
+	if (seq_has_overflowed(s))
 		goto release;
 
 	if (seq_print_acct(s, ct, IP_CT_DIR_ORIGINAL))
 		goto release;
 
 	if (!(test_bit(IPS_SEEN_REPLY_BIT, &ct->status)))
-		if (seq_printf(s, "[UNREPLIED] "))
-			goto release;
+		seq_printf(s, "[UNREPLIED] ");
 
-	if (print_tuple(s, &ct->tuplehash[IP_CT_DIR_REPLY].tuple,
-			l3proto, l4proto))
-		goto release;
+	print_tuple(s, &ct->tuplehash[IP_CT_DIR_REPLY].tuple,
+		    l3proto, l4proto);
 
 	if (seq_print_acct(s, ct, IP_CT_DIR_REPLY))
 		goto release;
 
 	if (test_bit(IPS_ASSURED_BIT, &ct->status))
-		if (seq_printf(s, "[ASSURED] "))
-			goto release;
+		seq_printf(s, "[ASSURED] ");
 
-#if defined(CONFIG_NF_CONNTRACK_MARK)
-	if (seq_printf(s, "mark=%u ", ct->mark))
+	if (seq_has_overflowed(s))
 		goto release;
+
+#if defined(CONFIG_NF_CONNTRACK_MARK)
+	seq_printf(s, "mark=%u ", ct->mark);
 #endif
 
-	if (ct_show_secctx(s, ct))
-		goto release;
+	ct_show_secctx(s, ct);
 
 #ifdef CONFIG_NF_CONNTRACK_ZONES
-	if (seq_printf(s, "zone=%u ", nf_ct_zone(ct)))
-		goto release;
+	seq_printf(s, "zone=%u ", nf_ct_zone(ct));
 #endif
 
-	if (ct_show_delta_time(s, ct))
-		goto release;
+	ct_show_delta_time(s, ct);
+
+	seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use));
 
-	if (seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use)))
+	if (seq_has_overflowed(s))
 		goto release;
 
 	ret = 0;

net/netfilter/nf_log.c

@@ -294,19 +294,19 @@ static int seq_show(struct seq_file *s, void *v)
 {
 	loff_t *pos = v;
 	const struct nf_logger *logger;
-	int i, ret;
+	int i;
 	struct net *net = seq_file_net(s);
 
 	logger = rcu_dereference_protected(net->nf.nf_loggers[*pos],
 					   lockdep_is_held(&nf_log_mutex));
 
 	if (!logger)
-		ret = seq_printf(s, "%2lld NONE (", *pos);
+		seq_printf(s, "%2lld NONE (", *pos);
 	else
-		ret = seq_printf(s, "%2lld %s (", *pos, logger->name);
+		seq_printf(s, "%2lld %s (", *pos, logger->name);
 
-	if (ret < 0)
-		return ret;
+	if (seq_has_overflowed(s))
+		return -ENOSPC;
 
 	for (i = 0; i < NF_LOG_TYPE_MAX; i++) {
 		if (loggers[*pos][i] == NULL)
@@ -314,17 +314,19 @@ static int seq_show(struct seq_file *s, void *v)
 
 		logger = rcu_dereference_protected(loggers[*pos][i],
 					   lockdep_is_held(&nf_log_mutex));
-		ret = seq_printf(s, "%s", logger->name);
-		if (ret < 0)
-			return ret;
-		if (i == 0 && loggers[*pos][i + 1] != NULL) {
-			ret = seq_printf(s, ",");
-			if (ret < 0)
-				return ret;
-		}
+		seq_printf(s, "%s", logger->name);
+		if (i == 0 && loggers[*pos][i + 1] != NULL)
+			seq_printf(s, ",");
+
+		if (seq_has_overflowed(s))
+			return -ENOSPC;
 	}
 
-	return seq_printf(s, ")\n");
+	seq_printf(s, ")\n");
+
+	if (seq_has_overflowed(s))
+		return -ENOSPC;
+	return 0;
 }
 
 static const struct seq_operations nflog_seq_ops = {

net/netfilter/nfnetlink_queue_core.c

@@ -1242,12 +1242,13 @@ static int seq_show(struct seq_file *s, void *v)
 {
 	const struct nfqnl_instance *inst = v;
 
-	return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
-			  inst->queue_num,
-			  inst->peer_portid, inst->queue_total,
-			  inst->copy_mode, inst->copy_range,
-			  inst->queue_dropped, inst->queue_user_dropped,
-			  inst->id_sequence, 1);
+	seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
+		   inst->queue_num,
+		   inst->peer_portid, inst->queue_total,
+		   inst->copy_mode, inst->copy_range,
+		   inst->queue_dropped, inst->queue_user_dropped,
+		   inst->id_sequence, 1);
+	return seq_has_overflowed(s);
 }
 
 static const struct seq_operations nfqnl_seq_ops = {

net/netfilter/x_tables.c

@@ -947,9 +947,10 @@ static int xt_table_seq_show(struct seq_file *seq, void *v)
 {
 	struct xt_table *table = list_entry(v, struct xt_table, list);
 
-	if (strlen(table->name))
-		return seq_printf(seq, "%s\n", table->name);
-	else
+	if (strlen(table->name)) {
+		seq_printf(seq, "%s\n", table->name);
+		return seq_has_overflowed(seq);
+	} else
 		return 0;
 }
 
@@ -1086,8 +1087,10 @@ static int xt_match_seq_show(struct seq_file *seq, void *v)
 		if (trav->curr == trav->head)
 			return 0;
 		match = list_entry(trav->curr, struct xt_match, list);
-		return (*match->name == '\0') ? 0 :
-		       seq_printf(seq, "%s\n", match->name);
+		if (*match->name == '\0')
+			return 0;
+		seq_printf(seq, "%s\n", match->name);
+		return seq_has_overflowed(seq);
 	}
 	return 0;
 }
@@ -1139,8 +1142,10 @@ static int xt_target_seq_show(struct seq_file *seq, void *v)
 		if (trav->curr == trav->head)
 			return 0;
 		target = list_entry(trav->curr, struct xt_target, list);
-		return (*target->name == '\0') ? 0 :
-		       seq_printf(seq, "%s\n", target->name);
+		if (*target->name == '\0')
+			return 0;
+		seq_printf(seq, "%s\n", target->name);
+		return seq_has_overflowed(seq);
 	}
 	return 0;
 }

net/netfilter/xt_hashlimit.c

@@ -789,7 +789,6 @@ static void dl_seq_stop(struct seq_file *s, void *v)
 static int dl_seq_real_show(struct dsthash_ent *ent, u_int8_t family,
 				   struct seq_file *s)
 {
-	int res;
 	const struct xt_hashlimit_htable *ht = s->private;
 
 	spin_lock(&ent->lock);
@@ -798,33 +797,32 @@ static int dl_seq_real_show(struct dsthash_ent *ent, u_int8_t family,
 
 	switch (family) {
 	case NFPROTO_IPV4:
-		res = seq_printf(s, "%ld %pI4:%u->%pI4:%u %u %u %u\n",
-				 (long)(ent->expires - jiffies)/HZ,
-				 &ent->dst.ip.src,
-				 ntohs(ent->dst.src_port),
-				 &ent->dst.ip.dst,
-				 ntohs(ent->dst.dst_port),
-				 ent->rateinfo.credit, ent->rateinfo.credit_cap,
-				 ent->rateinfo.cost);
+		seq_printf(s, "%ld %pI4:%u->%pI4:%u %u %u %u\n",
+			   (long)(ent->expires - jiffies)/HZ,
+			   &ent->dst.ip.src,
+			   ntohs(ent->dst.src_port),
+			   &ent->dst.ip.dst,
+			   ntohs(ent->dst.dst_port),
+			   ent->rateinfo.credit, ent->rateinfo.credit_cap,
+			   ent->rateinfo.cost);
 		break;
 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
 	case NFPROTO_IPV6:
-		res = seq_printf(s, "%ld %pI6:%u->%pI6:%u %u %u %u\n",
-				 (long)(ent->expires - jiffies)/HZ,
-				 &ent->dst.ip6.src,
-				 ntohs(ent->dst.src_port),
-				 &ent->dst.ip6.dst,
-				 ntohs(ent->dst.dst_port),
-				 ent->rateinfo.credit, ent->rateinfo.credit_cap,
-				 ent->rateinfo.cost);
+		seq_printf(s, "%ld %pI6:%u->%pI6:%u %u %u %u\n",
+			   (long)(ent->expires - jiffies)/HZ,
+			   &ent->dst.ip6.src,
+			   ntohs(ent->dst.src_port),
+			   &ent->dst.ip6.dst,
+			   ntohs(ent->dst.dst_port),
+			   ent->rateinfo.credit, ent->rateinfo.credit_cap,
+			   ent->rateinfo.cost);
 		break;
 #endif
 	default:
 		BUG();
-		res = 0;
 	}
 	spin_unlock(&ent->lock);
-	return res;
+	return seq_has_overflowed(s);
 }
 
 static int dl_seq_show(struct seq_file *s, void *v)