#include <linux/log2.h>
#include <linux/uaccess.h>
-static void _kfifo_init(struct kfifo *fifo, unsigned char *buffer,
+static void _kfifo_init(struct kfifo *fifo, void *buffer,
unsigned int size)
{
fifo->buffer = buffer;
* kfifo_init - initialize a FIFO using a preallocated buffer
* @fifo: the fifo to assign the buffer
* @buffer: the preallocated buffer to be used.
- * @size: the size of the internal buffer, this have to be a power of 2.
+ * @size: the size of the internal buffer, this has to be a power of 2.
*
*/
-void kfifo_init(struct kfifo *fifo, unsigned char *buffer, unsigned int size)
+void kfifo_init(struct kfifo *fifo, void *buffer, unsigned int size)
{
/* size must be a power of 2 */
BUG_ON(!is_power_of_2(size));
buffer = kmalloc(size, gfp_mask);
if (!buffer) {
- _kfifo_init(fifo, 0, 0);
+ _kfifo_init(fifo, NULL, 0);
return -ENOMEM;
}
void kfifo_free(struct kfifo *fifo)
{
kfree(fifo->buffer);
+ _kfifo_init(fifo, NULL, 0);
}
EXPORT_SYMBOL(kfifo_free);
memcpy(to + l, fifo->buffer, len - l);
}
-static inline unsigned int __kfifo_from_user_data(struct kfifo *fifo,
- const void __user *from, unsigned int len, unsigned int off)
+static inline int __kfifo_from_user_data(struct kfifo *fifo,
+ const void __user *from, unsigned int len, unsigned int off,
+ unsigned *lenout)
{
unsigned int l;
int ret;
/* first put the data starting from fifo->in to buffer end */
l = min(len, fifo->size - off);
ret = copy_from_user(fifo->buffer + off, from, l);
-
- if (unlikely(ret))
- return ret + len - l;
+ if (unlikely(ret)) {
+ *lenout = ret;
+ return -EFAULT;
+ }
+ *lenout = l;
/* then put the rest (if any) at the beginning of the buffer */
- return copy_from_user(fifo->buffer, from + l, len - l);
+ ret = copy_from_user(fifo->buffer, from + l, len - l);
+ *lenout += ret ? ret : len - l;
+ return ret ? -EFAULT : 0;
}
-static inline unsigned int __kfifo_to_user_data(struct kfifo *fifo,
- void __user *to, unsigned int len, unsigned int off)
+static inline int __kfifo_to_user_data(struct kfifo *fifo,
+ void __user *to, unsigned int len, unsigned int off, unsigned *lenout)
{
unsigned int l;
int ret;
/* first get the data from fifo->out until the end of the buffer */
l = min(len, fifo->size - off);
ret = copy_to_user(to, fifo->buffer + off, l);
-
- if (unlikely(ret))
- return ret + len - l;
+ *lenout = l;
+ if (unlikely(ret)) {
+ *lenout -= ret;
+ return -EFAULT;
+ }
/* then get the rest (if any) from the beginning of the buffer */
- return copy_to_user(to + l, fifo->buffer, len - l);
+ len -= l;
+ ret = copy_to_user(to + l, fifo->buffer, len);
+ if (unlikely(ret)) {
+ *lenout += len - ret;
+ return -EFAULT;
+ }
+ *lenout += len;
+ return 0;
}
unsigned int __kfifo_in_n(struct kfifo *fifo,
* Note that with only one concurrent reader and one concurrent
* writer, you don't need extra locking to use these functions.
*/
-unsigned int kfifo_in(struct kfifo *fifo, const unsigned char *from,
+unsigned int kfifo_in(struct kfifo *fifo, const void *from,
unsigned int len)
{
len = min(kfifo_avail(fifo), len);
* Note that with only one concurrent reader and one concurrent
* writer, you don't need extra locking to use these functions.
*/
-unsigned int kfifo_out(struct kfifo *fifo, unsigned char *to, unsigned int len)
+unsigned int kfifo_out(struct kfifo *fifo, void *to, unsigned int len)
{
len = min(kfifo_len(fifo), len);
}
EXPORT_SYMBOL(kfifo_out);
+/**
+ * kfifo_out_peek - copy some data from the FIFO, but do not remove it
+ * @fifo: the fifo to be used.
+ * @to: where the data must be copied.
+ * @len: the size of the destination buffer.
+ * @offset: offset into the fifo
+ *
+ * This function copies at most @len bytes at @offset from the FIFO
+ * into the @to buffer and returns the number of copied bytes.
+ * The data is not removed from the FIFO.
+ */
+unsigned int kfifo_out_peek(struct kfifo *fifo, void *to, unsigned int len,
+ unsigned offset)
+{
+ len = min(kfifo_len(fifo), len + offset);
+
+ __kfifo_out_data(fifo, to, len, offset);
+ return len;
+}
+EXPORT_SYMBOL(kfifo_out_peek);
+
unsigned int __kfifo_out_generic(struct kfifo *fifo,
void *to, unsigned int len, unsigned int recsize,
unsigned int *total)
unsigned int __kfifo_from_user_n(struct kfifo *fifo,
const void __user *from, unsigned int len, unsigned int recsize)
{
+ unsigned total;
+
if (kfifo_avail(fifo) < len + recsize)
return len + 1;
- return __kfifo_from_user_data(fifo, from, len, recsize);
+ __kfifo_from_user_data(fifo, from, len, recsize, &total);
+ return total;
}
EXPORT_SYMBOL(__kfifo_from_user_n);
* @fifo: the fifo to be used.
* @from: pointer to the data to be added.
* @len: the length of the data to be added.
+ * @total: the actual returned data length.
*
* This function copies at most @len bytes from the @from into the
- * FIFO depending and returns the number of copied bytes.
+ * FIFO depending and returns -EFAULT/0.
*
* Note that with only one concurrent reader and one concurrent
* writer, you don't need extra locking to use these functions.
*/
-unsigned int kfifo_from_user(struct kfifo *fifo,
- const void __user *from, unsigned int len)
+int kfifo_from_user(struct kfifo *fifo,
+ const void __user *from, unsigned int len, unsigned *total)
{
+ int ret;
len = min(kfifo_avail(fifo), len);
- len -= __kfifo_from_user_data(fifo, from, len, 0);
+ ret = __kfifo_from_user_data(fifo, from, len, 0, total);
+ if (ret)
+ return ret;
__kfifo_add_in(fifo, len);
- return len;
+ return 0;
}
EXPORT_SYMBOL(kfifo_from_user);
void __user *to, unsigned int len, unsigned int reclen,
unsigned int recsize)
{
- unsigned int ret;
+ unsigned int ret, total;
if (kfifo_len(fifo) < reclen + recsize)
return len;
- ret = __kfifo_to_user_data(fifo, to, reclen, recsize);
+ ret = __kfifo_to_user_data(fifo, to, reclen, recsize, &total);
if (likely(ret == 0))
__kfifo_add_out(fifo, reclen + recsize);
- return ret;
+ return total;
}
EXPORT_SYMBOL(__kfifo_to_user_n);
* @fifo: the fifo to be used.
* @to: where the data must be copied.
* @len: the size of the destination buffer.
+ * @lenout: pointer to output variable with copied data
*
* This function copies at most @len bytes from the FIFO into the
- * @to buffer and returns the number of copied bytes.
+ * @to buffer and 0 or -EFAULT.
*
* Note that with only one concurrent reader and one concurrent
* writer, you don't need extra locking to use these functions.
*/
-unsigned int kfifo_to_user(struct kfifo *fifo,
- void __user *to, unsigned int len)
+int kfifo_to_user(struct kfifo *fifo,
+ void __user *to, unsigned int len, unsigned *lenout)
{
+ int ret;
len = min(kfifo_len(fifo), len);
- len -= __kfifo_to_user_data(fifo, to, len, 0);
- __kfifo_add_out(fifo, len);
- return len;
+ ret = __kfifo_to_user_data(fifo, to, len, 0, lenout);
+ __kfifo_add_out(fifo, *lenout);
+ return ret;
}
EXPORT_SYMBOL(kfifo_to_user);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff