From: Russell King rmk+kernel@arm.linux.org.uk
Ensure that the ring buffer wraps when we fill the buffer.
Signed-off-by: Russell King rmk+kernel@arm.linux.org.uk --- drivers/staging/etnaviv/etnaviv_buffer.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/etnaviv/etnaviv_buffer.c b/drivers/staging/etnaviv/etnaviv_buffer.c index a93d5091828e..a8b42a1ec7db 100644 --- a/drivers/staging/etnaviv/etnaviv_buffer.c +++ b/drivers/staging/etnaviv/etnaviv_buffer.c @@ -30,7 +30,7 @@ static inline void OUT(struct etnaviv_gem_object *buffer, uint32_t data) { u32 *vaddr = (u32 *)buffer->vaddr; - BUG_ON(buffer->offset * sizeof(*vaddr) >= buffer->base.size); + BUG_ON(buffer->offset >= buffer->base.size / sizeof(*vaddr));
vaddr[buffer->offset++] = data; } @@ -154,6 +154,12 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, unsigned int event, struct et if (drm_debug & DRM_UT_DRIVER) etnaviv_buffer_dump(gpu, buffer, 0, 0x50);
+ /* + * if we are going to completely overflow the buffer, we need to wrap. + */ + if (buffer->offset + 6 > buffer->base.size / sizeof(uint32_t)) + buffer->offset = 0; + /* save offset back into main buffer */ back = buffer->offset; link_target = buffer->paddr + buffer->offset * 4;