From f24f0b495b17df33c03f3b758b1461385e9f0e50 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Fri, 2 Sep 2016 05:58:21 -0700 Subject: [PATCH] Drivers: hv: ring_buffer: use wrap around mappings in hv_copy{from, to}_ringbuffer() With wrap around mappings for ring buffers we can always use a single memcpy() to do the job. Signed-off-by: Vitaly Kuznetsov Signed-off-by: K. Y. Srinivasan Tested-by: Dexuan Cui Signed-off-by: Greg Kroah-Hartman --- drivers/hv/ring_buffer.c | 24 +++--------------------- 1 file changed, 3 insertions(+), 21 deletions(-) diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 7e21c2c82ad1..08043da1a61c 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -172,18 +172,7 @@ static u32 hv_copyfrom_ringbuffer( 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); - + memcpy(dest, ring_buffer + start_read_offset, destlen); start_read_offset += destlen; start_read_offset %= ring_buffer_size; @@ -204,15 +193,8 @@ static u32 hv_copyto_ringbuffer( { 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); + + memcpy(ring_buffer + start_write_offset, src, srclen); start_write_offset += srclen; start_write_offset %= ring_buffer_size; -- 2.39.2