linux-kernel - Applied "regmap: debugfs: Use seq_file for the access map" to the regmap tree

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Tue, 05 Jan 2016 19:06:36 +0000
From:	Mark Brown <broonie@...nel.org>
To:	Mark Brown <broonie@...nel.org>
Cc:	linux-kernel@...r.kernel.org
Subject: Applied "regmap: debugfs: Use seq_file for the access map" to the regmap tree

The patch

   regmap: debugfs: Use seq_file for the access map

has been applied to the regmap tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 8da61f24cc4a4a66ecae69aa9b9aa8fd989a8969 Mon Sep 17 00:00:00 2001
From: Mark Brown <broonie@...nel.org>
Date: Tue, 20 Oct 2015 15:40:59 +0100
Subject: [PATCH] regmap: debugfs: Use seq_file for the access map

Unlike the registers file we don't have any substantial performance
concerns rendering the entire file (it involves no device accesses) so
just use seq_printf() to simplify the code.

Signed-off-by: Mark Brown <broonie@...nel.org>
---
 drivers/base/regmap/regmap-debugfs.c | 69 ++++++++++--------------------------
 1 file changed, 18 insertions(+), 51 deletions(-)

diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
index 3f0a7e262d69..1ee3d40861c7 100644
--- a/drivers/base/regmap/regmap-debugfs.c
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -397,72 +397,39 @@ static const struct file_operations regmap_reg_ranges_fops = {
 	.llseek = default_llseek,
 };
 
-static ssize_t regmap_access_read_file(struct file *file,
-				       char __user *user_buf, size_t count,
-				       loff_t *ppos)
+static int regmap_access_show(struct seq_file *s, void *ignored)
 {
-	int reg_len, tot_len;
-	size_t buf_pos = 0;
-	loff_t p = 0;
-	ssize_t ret;
-	int i;
-	struct regmap *map = file->private_data;
-	char *buf;
-
-	if (*ppos < 0 || !count)
-		return -EINVAL;
+	struct regmap *map = s->private;
+	int i, reg_len;
 
-	buf = kmalloc(count, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	/* Calculate the length of a fixed format  */
 	reg_len = regmap_calc_reg_len(map->max_register);
-	tot_len = reg_len + 10; /* ': R W V P\n' */
 
 	for (i = 0; i <= map->max_register; i += map->reg_stride) {
 		/* Ignore registers which are neither readable nor writable */
 		if (!regmap_readable(map, i) && !regmap_writeable(map, i))
 			continue;
 
-		/* If we're in the region the user is trying to read */
-		if (p >= *ppos) {
-			/* ...but not beyond it */
-			if (buf_pos + tot_len + 1 >= count)
-				break;
-
-			/* Format the register */
-			snprintf(buf + buf_pos, count - buf_pos,
-				 "%.*x: %c %c %c %c\n",
-				 reg_len, i,
-				 regmap_readable(map, i) ? 'y' : 'n',
-				 regmap_writeable(map, i) ? 'y' : 'n',
-				 regmap_volatile(map, i) ? 'y' : 'n',
-				 regmap_precious(map, i) ? 'y' : 'n');
-
-			buf_pos += tot_len;
-		}
-		p += tot_len;
-	}
-
-	ret = buf_pos;
-
-	if (copy_to_user(user_buf, buf, buf_pos)) {
-		ret = -EFAULT;
-		goto out;
+		/* Format the register */
+		seq_printf(s, "%.*x: %c %c %c %c\n", reg_len, i,
+			   regmap_readable(map, i) ? 'y' : 'n',
+			   regmap_writeable(map, i) ? 'y' : 'n',
+			   regmap_volatile(map, i) ? 'y' : 'n',
+			   regmap_precious(map, i) ? 'y' : 'n');
 	}
 
-	*ppos += buf_pos;
+	return 0;
+}
 
-out:
-	kfree(buf);
-	return ret;
+static int access_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, regmap_access_show, inode->i_private);
 }
 
 static const struct file_operations regmap_access_fops = {
-	.open = simple_open,
-	.read = regmap_access_read_file,
-	.llseek = default_llseek,
+	.open		= access_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
 };
 
 static ssize_t regmap_cache_only_write_file(struct file *file,
-- 
2.7.0.rc3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/