[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@gmail.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 6f044584bdc6ac3b38c4a20949bfcbabb5f292ae..6b83aee8abb8ee137c51b4d07075a62a5610d87a 100644 (file)
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -170,16 +170,22 @@ static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t
 
        /* 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 *file, char __user *buf, size_t count,loff_t
                        return ret;
                }
 
-               kfree(kbuf);
        }
 
+       kfree(kbuf);
        return total_retlen;
 } /* mtd_read */
 
@@ -241,18 +247,21 @@ static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count
        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 *file, const char __user *buf, size_t count
                        kfree(kbuf);
                        return ret;
                }
-
-               kfree(kbuf);
        }
 
+       kfree(kbuf);
        return total_retlen;
 } /* mtd_write */