#include <linux/err.h>
#include <linux/kfifo.h>
#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);
/**
- * kfifo_in - puts some data into the FIFO
+ * kfifo_skip - skip output data
* @fifo: the fifo to be used.
- * @from: the data to be added.
- * @len: the length of the data to be added.
- *
- * This function copies at most @len bytes from the @from buffer into
- * the FIFO depending on the free space, and returns the number of
- * bytes copied.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these functions.
+ * @len: number of bytes to skip
*/
-unsigned int kfifo_in(struct kfifo *fifo,
- const unsigned char *from, unsigned int len)
+void kfifo_skip(struct kfifo *fifo, unsigned int len)
{
- unsigned int l;
+ if (len < kfifo_len(fifo)) {
+ __kfifo_add_out(fifo, len);
+ return;
+ }
+ kfifo_reset_out(fifo);
+}
+EXPORT_SYMBOL(kfifo_skip);
- len = min(len, fifo->size - fifo->in + fifo->out);
+static inline void __kfifo_in_data(struct kfifo *fifo,
+ const void *from, unsigned int len, unsigned int off)
+{
+ unsigned int l;
/*
* Ensure that we sample the fifo->out index -before- we
smp_mb();
+ off = __kfifo_off(fifo, fifo->in + off);
+
/* first put the data starting from fifo->in to buffer end */
- l = min(len, fifo->size - (fifo->in & (fifo->size - 1)));
- memcpy(fifo->buffer + (fifo->in & (fifo->size - 1)), from, l);
+ l = min(len, fifo->size - off);
+ memcpy(fifo->buffer + off, from, l);
/* then put the rest (if any) at the beginning of the buffer */
memcpy(fifo->buffer, from + l, len - l);
+}
+
+static inline void __kfifo_out_data(struct kfifo *fifo,
+ void *to, unsigned int len, unsigned int off)
+{
+ unsigned int l;
+
+ /*
+ * Ensure that we sample the fifo->in index -before- we
+ * start removing bytes from the kfifo.
+ */
+
+ smp_rmb();
+
+ off = __kfifo_off(fifo, fifo->out + off);
+
+ /* first get the data from fifo->out until the end of the buffer */
+ l = min(len, fifo->size - off);
+ memcpy(to, fifo->buffer + off, l);
+
+ /* then get the rest (if any) from the beginning of the buffer */
+ memcpy(to + l, fifo->buffer, len - l);
+}
+
+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;
+
+ /*
+ * Ensure that we sample the fifo->out index -before- we
+ * start putting bytes into the kfifo.
+ */
+
+ smp_mb();
+
+ off = __kfifo_off(fifo, fifo->in + off);
+
+ /* 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)) {
+ *lenout = ret;
+ return -EFAULT;
+ }
+ *lenout = l;
+
+ /* then put the rest (if any) at the beginning of the buffer */
+ ret = copy_from_user(fifo->buffer, from + l, len - l);
+ *lenout += ret ? ret : len - l;
+ return ret ? -EFAULT : 0;
+}
+
+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;
/*
- * Ensure that we add the bytes to the kfifo -before-
- * we update the fifo->in index.
+ * Ensure that we sample the fifo->in index -before- we
+ * start removing bytes from the kfifo.
*/
- smp_wmb();
+ smp_rmb();
+
+ off = __kfifo_off(fifo, fifo->out + off);
+
+ /* 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);
+ *lenout = l;
+ if (unlikely(ret)) {
+ *lenout -= ret;
+ return -EFAULT;
+ }
+
+ /* then get the rest (if any) from the beginning of the buffer */
+ 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,
+ const void *from, unsigned int len, unsigned int recsize)
+{
+ if (kfifo_avail(fifo) < len + recsize)
+ return len + 1;
- fifo->in += len;
+ __kfifo_in_data(fifo, from, len, recsize);
+ return 0;
+}
+EXPORT_SYMBOL(__kfifo_in_n);
+/**
+ * kfifo_in - puts some data into the FIFO
+ * @fifo: the fifo to be used.
+ * @from: the data to be added.
+ * @len: the length of the data to be added.
+ *
+ * This function copies at most @len bytes from the @from buffer into
+ * the FIFO depending on the free space, and returns the number of
+ * bytes copied.
+ *
+ * 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 void *from,
+ unsigned int len)
+{
+ len = min(kfifo_avail(fifo), len);
+
+ __kfifo_in_data(fifo, from, len, 0);
+ __kfifo_add_in(fifo, len);
return len;
}
EXPORT_SYMBOL(kfifo_in);
+unsigned int __kfifo_in_generic(struct kfifo *fifo,
+ const void *from, unsigned int len, unsigned int recsize)
+{
+ return __kfifo_in_rec(fifo, from, len, recsize);
+}
+EXPORT_SYMBOL(__kfifo_in_generic);
+
+unsigned int __kfifo_out_n(struct kfifo *fifo,
+ void *to, unsigned int len, unsigned int recsize)
+{
+ if (kfifo_len(fifo) < len + recsize)
+ return len;
+
+ __kfifo_out_data(fifo, to, len, recsize);
+ __kfifo_add_out(fifo, len + recsize);
+ return 0;
+}
+EXPORT_SYMBOL(__kfifo_out_n);
+
/**
* kfifo_out - gets some data from the FIFO
* @fifo: the fifo to be used.
* 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)
{
- unsigned int l;
+ len = min(kfifo_len(fifo), len);
- len = min(len, fifo->in - fifo->out);
+ __kfifo_out_data(fifo, to, len, 0);
+ __kfifo_add_out(fifo, len);
- /*
- * Ensure that we sample the fifo->in index -before- we
- * start removing bytes from the kfifo.
- */
+ return len;
+}
+EXPORT_SYMBOL(kfifo_out);
- smp_rmb();
+/**
+ * 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);
- /* first get the data from fifo->out until the end of the buffer */
- l = min(len, fifo->size - (fifo->out & (fifo->size - 1)));
- memcpy(to, fifo->buffer + (fifo->out & (fifo->size - 1)), l);
+ __kfifo_out_data(fifo, to, len, offset);
+ return len;
+}
+EXPORT_SYMBOL(kfifo_out_peek);
- /* then get the rest (if any) from the beginning of the buffer */
- memcpy(to + l, fifo->buffer, len - l);
+unsigned int __kfifo_out_generic(struct kfifo *fifo,
+ void *to, unsigned int len, unsigned int recsize,
+ unsigned int *total)
+{
+ return __kfifo_out_rec(fifo, to, len, recsize, total);
+}
+EXPORT_SYMBOL(__kfifo_out_generic);
- /*
- * Ensure that we remove the bytes from the kfifo -before-
- * we update the fifo->out index.
- */
+unsigned int __kfifo_from_user_n(struct kfifo *fifo,
+ const void __user *from, unsigned int len, unsigned int recsize)
+{
+ unsigned total;
- smp_mb();
+ if (kfifo_avail(fifo) < len + recsize)
+ return len + 1;
- fifo->out += len;
+ __kfifo_from_user_data(fifo, from, len, recsize, &total);
+ return total;
+}
+EXPORT_SYMBOL(__kfifo_from_user_n);
- return len;
+/**
+ * kfifo_from_user - puts some data from user space into the FIFO
+ * @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 -EFAULT/0.
+ *
+ * Note that with only one concurrent reader and one concurrent
+ * writer, you don't need extra locking to use these functions.
+ */
+int kfifo_from_user(struct kfifo *fifo,
+ const void __user *from, unsigned int len, unsigned *total)
+{
+ int ret;
+ len = min(kfifo_avail(fifo), len);
+ ret = __kfifo_from_user_data(fifo, from, len, 0, total);
+ if (ret)
+ return ret;
+ __kfifo_add_in(fifo, len);
+ return 0;
}
-EXPORT_SYMBOL(kfifo_out);
+EXPORT_SYMBOL(kfifo_from_user);
+
+unsigned int __kfifo_from_user_generic(struct kfifo *fifo,
+ const void __user *from, unsigned int len, unsigned int recsize)
+{
+ return __kfifo_from_user_rec(fifo, from, len, recsize);
+}
+EXPORT_SYMBOL(__kfifo_from_user_generic);
+
+unsigned int __kfifo_to_user_n(struct kfifo *fifo,
+ void __user *to, unsigned int len, unsigned int reclen,
+ unsigned int recsize)
+{
+ unsigned int ret, total;
+
+ if (kfifo_len(fifo) < reclen + recsize)
+ return len;
+
+ ret = __kfifo_to_user_data(fifo, to, reclen, recsize, &total);
+
+ if (likely(ret == 0))
+ __kfifo_add_out(fifo, reclen + recsize);
+
+ return total;
+}
+EXPORT_SYMBOL(__kfifo_to_user_n);
+
+/**
+ * kfifo_to_user - gets data from the FIFO and write it to user space
+ * @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 0 or -EFAULT.
+ *
+ * Note that with only one concurrent reader and one concurrent
+ * writer, you don't need extra locking to use these functions.
+ */
+int kfifo_to_user(struct kfifo *fifo,
+ void __user *to, unsigned int len, unsigned *lenout)
+{
+ int ret;
+ len = min(kfifo_len(fifo), len);
+ ret = __kfifo_to_user_data(fifo, to, len, 0, lenout);
+ __kfifo_add_out(fifo, *lenout);
+ return ret;
+}
+EXPORT_SYMBOL(kfifo_to_user);
+
+unsigned int __kfifo_to_user_generic(struct kfifo *fifo,
+ void __user *to, unsigned int len, unsigned int recsize,
+ unsigned int *total)
+{
+ return __kfifo_to_user_rec(fifo, to, len, recsize, total);
+}
+EXPORT_SYMBOL(__kfifo_to_user_generic);
+
+unsigned int __kfifo_peek_generic(struct kfifo *fifo, unsigned int recsize)
+{
+ if (recsize == 0)
+ return kfifo_avail(fifo);
+
+ return __kfifo_peek_n(fifo, recsize);
+}
+EXPORT_SYMBOL(__kfifo_peek_generic);
+
+void __kfifo_skip_generic(struct kfifo *fifo, unsigned int recsize)
+{
+ __kfifo_skip_rec(fifo, recsize);
+}
+EXPORT_SYMBOL(__kfifo_skip_generic);
+
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff