[PATCH] Remove unnecessary kmalloc/kfree calls in mtdchar

[Linux-MTD Mailing List]

commit b802c0741103aa92251d536c115874d51f802ec8
tree cf2cb539e68b224ad06b4a43350454b847543381
parent cd2866faaa0efd9af18fe4a86d129cbd99240796
author Thago Galesi <thiagogalesi at gmail.com> Mon, 17 Apr 2006 17:38:15 +0100
committer David Woodhouse <dwmw2 at infradead.org> Mon, 17 Apr 2006 17:38:15 +0100

[PATCH] Remove unnecessary kmalloc/kfree calls in mtdchar

This patch removes repeated calls to kmalloc / kfree in mtd_write /
mtd_read functions, replacing them by a single kmalloc / kfree pair.

Signed-off-by: Thiago Galesi <thiagogalesi at gmail.com>
Signed-off-by: David Woodhouse <dwmw2 at infradead.org>

 drivers/mtd/mtdchar.c |   34 +++++++++++++++++++++-------------
 1 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 6f04458..6b83aee 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -170,16 +170,22 @@ static ssize_t mtd_read(struct file *fil
 
 	/* FIXME: Use kiovec in 2.5 to lock down the user's buffers
 	   and pass them directly to the MTD functions */
+
+	if (count > MAX_KMALLOC_SIZE)
+		kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
+	else
+		kbuf=kmalloc(count, GFP_KERNEL);
+
+	if (!kbuf)
+		return -ENOMEM;
+
 	while (count) {
+
 		if (count > MAX_KMALLOC_SIZE)
 			len = MAX_KMALLOC_SIZE;
 		else
 			len = count;
 
-		kbuf=kmalloc(len,GFP_KERNEL);
-		if (!kbuf)
-			return -ENOMEM;
-
 		switch (MTD_MODE(file)) {
 		case MTD_MODE_OTP_FACT:
 			ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
@@ -215,9 +221,9 @@ static ssize_t mtd_read(struct file *fil
 			return ret;
 		}
 
-		kfree(kbuf);
 	}
 
+	kfree(kbuf);
 	return total_retlen;
 } /* mtd_read */
 
@@ -241,18 +247,21 @@ static ssize_t mtd_write(struct file *fi
 	if (!count)
 		return 0;
 
+	if (count > MAX_KMALLOC_SIZE)
+		kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
+	else
+		kbuf=kmalloc(count, GFP_KERNEL);
+
+	if (!kbuf)
+		return -ENOMEM;
+
 	while (count) {
+
 		if (count > MAX_KMALLOC_SIZE)
 			len = MAX_KMALLOC_SIZE;
 		else
 			len = count;
 
-		kbuf=kmalloc(len,GFP_KERNEL);
-		if (!kbuf) {
-			printk("kmalloc is null\n");
-			return -ENOMEM;
-		}
-
 		if (copy_from_user(kbuf, buf, len)) {
 			kfree(kbuf);
 			return -EFAULT;
@@ -282,10 +291,9 @@ static ssize_t mtd_write(struct file *fi
 			kfree(kbuf);
 			return ret;
 		}
-
-		kfree(kbuf);
 	}
 
+	kfree(kbuf);
 	return total_retlen;
 } /* mtd_write */