/*
*
* hv_copyfrom_ringbuffer()
*
* Helper routine to copy to source from ring buffer.
* Assume there is enough room. Handles wrap-around in src case only!!
*
*/
static u32 hv_copyfrom_ringbuffer(
struct hv_ring_buffer_info *ring_info,
void *dest,
u32 destlen,
u32 start_read_offset)
{
void *ring_buffer = hv_get_ring_buffer(ring_info);
u32 ring_buffer_size = hv_get_ring_buffersize(ring_info);
u32 frag_len;
/* wrap-around detected at the src */
if (destlen > ring_buffer_size - start_read_offset) {
frag_len = ring_buffer_size - start_read_offset;
memcpy(dest, ring_buffer + start_read_offset, frag_len);
memcpy(dest + frag_len, ring_buffer, destlen - frag_len);
} else
memcpy(dest, ring_buffer + start_read_offset, destlen);
start_read_offset += destlen;
start_read_offset %= ring_buffer_size;
return start_read_offset;
}
/*
* Helper routine to copy from source to ring buffer.
* Assume there is enough room. Handles wrap-around in dest case only!!
*/
static u32 hv_copyto_ringbuffer(
struct hv_ring_buffer_info *ring_info,
u32 start_write_offset,
void *src,
u32 srclen)
{
void *ring_buffer = hv_get_ring_buffer(ring_info);
u32 ring_buffer_size = hv_get_ring_buffersize(ring_info);
memcpy(ring_buffer + start_write_offset, src, srclen);
start_write_offset += srclen;
start_write_offset %= ring_buffer_size;
return start_write_offset;
}
/*
* Helper routine to copy to source from ring buffer.
* Assume there is enough room. Handles wrap-around in src case only!!
*/
static u32 hv_copyfrom_ringbuffer(
struct hv_ring_buffer_info *ring_info,
void *dest,
u32 destlen,
u32 start_read_offset)
{
void *ring_buffer = hv_get_ring_buffer(ring_info);
u32 ring_buffer_size = hv_get_ring_buffersize(ring_info);
memcpy(dest, ring_buffer + start_read_offset, destlen);
start_read_offset += destlen;
start_read_offset %= ring_buffer_size;
return start_read_offset;
}
/*
*
* hv_copyto_ringbuffer()
*
* Helper routine to copy from source to ring buffer.
* Assume there is enough room. Handles wrap-around in dest case only!!
*
*/
static u32 hv_copyto_ringbuffer(
struct hv_ring_buffer_info *ring_info,
u32 start_write_offset,
void *src,
u32 srclen)
{
void *ring_buffer = hv_get_ring_buffer(ring_info);
u32 ring_buffer_size = hv_get_ring_buffersize(ring_info);
u32 frag_len;
/* wrap-around detected! */
if (srclen > ring_buffer_size - start_write_offset) {
frag_len = ring_buffer_size - start_write_offset;
memcpy(ring_buffer + start_write_offset, src, frag_len);
memcpy(ring_buffer, src + frag_len, srclen - frag_len);
} else
memcpy(ring_buffer + start_write_offset, src, srclen);
start_write_offset += srclen;
start_write_offset %= ring_buffer_size;
return start_write_offset;
}
