nfs: disintegrate UAPI for nfs

This is to complete part of the Userspace API (UAPI) disintegration for which
the preparatory patches were pulled recently.  After these patches, userspace
headers will be segregated into:

        include/uapi/linux/.../foo.h

for the userspace interface stuff, and:

        include/linux/.../foo.h

for the strictly kernel internal stuff.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 27 insertions, 49 deletions

diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index 2340f6978d6..c5ca6ae5a30 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -526,73 +526,51 @@ struct array_data {
 	u32 elements;
 };
 
-static int u32_array_open(struct inode *inode, struct file *file)
-{
-	file->private_data = NULL;
-	return nonseekable_open(inode, file);
-}
-
-static size_t format_array(char *buf, size_t bufsize, const char *fmt,
-			   u32 *array, u32 array_size)
+static size_t u32_format_array(char *buf, size_t bufsize,
+			       u32 *array, int array_size)
 {
 	size_t ret = 0;
-	u32 i;
 
-	for (i = 0; i < array_size; i++) {
+	while (--array_size >= 0) {
 		size_t len;
+		char term = array_size ? ' ' : '\n';
 
-		len = snprintf(buf, bufsize, fmt, array[i]);
-		len++;	/* ' ' or '\n' */
+		len = snprintf(buf, bufsize, "%u%c", *array++, term);
 		ret += len;
 
-		if (buf) {
-			buf += len;
-			bufsize -= len;
-			buf[-1] = (i == array_size-1) ? '\n' : ' ';
-		}
+		buf += len;
+		bufsize -= len;
 	}
-
-	ret++;		/* \0 */
-	if (buf)
-		*buf = '\0';
-
 	return ret;
 }
 
-static char *format_array_alloc(const char *fmt, u32 *array,
-						u32 array_size)
+static int u32_array_open(struct inode *inode, struct file *file)
 {
-	size_t len = format_array(NULL, 0, fmt, array, array_size);
-	char *ret;
-
-	ret = kmalloc(len, GFP_KERNEL);
-	if (ret == NULL)
-		return NULL;
+	struct array_data *data = inode->i_private;
+	int size, elements = data->elements;
+	char *buf;
+
+	/*
+	 * Max size:
+	 *  - 10 digits + ' '/'\n' = 11 bytes per number
+	 *  - terminating NUL character
+	 */
+	size = elements*11;
+	buf = kmalloc(size+1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+	buf[size] = 0;
+
+	file->private_data = buf;
+	u32_format_array(buf, size, data->array, data->elements);
 
-	format_array(ret, len, fmt, array, array_size);
-	return ret;
+	return nonseekable_open(inode, file);
 }
 
 static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
 			      loff_t *ppos)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
-	struct array_data *data = inode->i_private;
-	size_t size;
-
-	if (*ppos == 0) {
-		if (file->private_data) {
-			kfree(file->private_data);
-			file->private_data = NULL;
-		}
-
-		file->private_data = format_array_alloc("%u", data->array,
-							      data->elements);
-	}
-
-	size = 0;
-	if (file->private_data)
-		size = strlen(file->private_data);
+	size_t size = strlen(file->private_data);
 
 	return simple_read_from_buffer(buf, len, ppos,
 					file->private_data, size);