procfs: use simple_read_from_buffer()

Cleanup using simple_read_from_buffer() in procfs.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index ff9c131e6b3062d2d1f4fd800557023a0936bf36..3c41149dea8875ba1431d25acb969ec75f197770 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -660,7 +660,6 @@ static ssize_t oom_adjust_read(struct file *file, char __user *buf,
        char buffer[PROC_NUMBUF];
        size_t len;
        int oom_adjust;
-       loff_t __ppos = *ppos;
 
        if (!task)
                return -ESRCH;
@@ -668,14 +667,8 @@ static ssize_t oom_adjust_read(struct file *file, char __user *buf,
        put_task_struct(task);
 
        len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
-       if (__ppos >= len)
-               return 0;
-       if (count > len-__ppos)
-               count = len-__ppos;
-       if (copy_to_user(buf, buffer + __ppos, count))
-               return -EFAULT;
-       *ppos = __ppos + count;
-       return count;
+
+       return simple_read_from_buffer(buf, count, ppos, buffer, len);
 }
 
 static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
@@ -823,7 +816,6 @@ static ssize_t seccomp_read(struct file *file, char __user *buf,
 {
        struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode);
        char __buf[20];
-       loff_t __ppos = *ppos;
        size_t len;
 
        if (!tsk)
@@ -831,14 +823,8 @@ static ssize_t seccomp_read(struct file *file, char __user *buf,
        /* no need to print the trailing zero, so use only len */
        len = sprintf(__buf, "%u\n", tsk->seccomp.mode);
        put_task_struct(tsk);
-       if (__ppos >= len)
-               return 0;
-       if (count > len - __ppos)
-               count = len - __ppos;
-       if (copy_to_user(buf, __buf + __ppos, count))
-               return -EFAULT;
-       *ppos = __ppos + count;
-       return count;
+
+       return simple_read_from_buffer(buf, count, ppos, __buf, len);
 }
 
 static ssize_t seccomp_write(struct file *file, const char __user *buf,
@@ -897,7 +883,6 @@ static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
        char buffer[PROC_NUMBUF];
        size_t len;
        int make_it_fail;
-       loff_t __ppos = *ppos;
 
        if (!task)
                return -ESRCH;
@@ -905,14 +890,8 @@ static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
        put_task_struct(task);
 
        len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
-       if (__ppos >= len)
-               return 0;
-       if (count > len-__ppos)
-               count = len-__ppos;
-       if (copy_to_user(buf, buffer + __ppos, count))
-               return -EFAULT;
-       *ppos = __ppos + count;
-       return count;
+
+       return simple_read_from_buffer(buf, count, ppos, buffer, len);
 }
 
 static ssize_t proc_fault_inject_write(struct file * file,
@@ -975,7 +954,7 @@ static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt,
 
        if (!tmp)
                return -ENOMEM;
-               
+
        inode = dentry->d_inode;
        path = d_path(dentry, mnt, tmp, PAGE_SIZE);
        len = PTR_ERR(path);