[media] coda: allocate bitstream buffer from REQBUFS, size depends on the format

Allocating the bitstream buffer only when the format is set allows to guarantee
that at least two frames fit into the bitstream buffer. For small frame sizes
a smaller bitstream buffer can be allocated. Since the bitstream buffer size now
depends on the format, replace CODA_MAX_FRAME_SIZE with ctx->bitstream.size
where appropriate and remove the now unused constant.
Since REQBUFS can be called multiple times, but the format can't be changed
unless REQBUFS 0 was called before, we can just keep the allocated context and
bitstream buffers if REQBUFS is called multiple times with a non-zero buffer
count.

[fixed a resource leak preventing repeatedly decoding]
Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/coda/coda-bit.c

@@ -15,6 +15,7 @@
 #include <linux/clk.h>
 #include <linux/irqreturn.h>
 #include <linux/kernel.h>
+#include <linux/log2.h>
 #include <linux/platform_device.h>
 #include <linux/reset.h>
 #include <linux/slab.h>
@@ -36,6 +37,8 @@
 #define CODA_DEFAULT_GAMMA	4096
 #define CODA9_DEFAULT_GAMMA	24576	/* 0.75 * 32768 */
 
+static void coda_free_bitstream_buffer(struct coda_ctx *ctx);
+
 static inline int coda_is_initialized(struct coda_dev *dev)
 {
 	return coda_read(dev, CODA_REG_BIT_CUR_PC) != 0;
@@ -389,21 +392,7 @@ static int coda_alloc_context_buffers(struct coda_ctx *ctx,
 	if (dev->devtype->product == CODA_DX6)
 		return 0;
 
-	if (ctx->psbuf.vaddr) {
-		v4l2_err(&dev->v4l2_dev, "psmembuf still allocated\n");
-		return -EBUSY;
-	}
-	if (ctx->slicebuf.vaddr) {
-		v4l2_err(&dev->v4l2_dev, "slicebuf still allocated\n");
-		return -EBUSY;
-	}
-	if (ctx->workbuf.vaddr) {
-		v4l2_err(&dev->v4l2_dev, "context buffer still allocated\n");
-		ret = -EBUSY;
-		return -ENOMEM;
-	}
-
-	if (q_data->fourcc == V4L2_PIX_FMT_H264) {
+	if (!ctx->slicebuf.vaddr && q_data->fourcc == V4L2_PIX_FMT_H264) {
 		/* worst case slice size */
 		size = (DIV_ROUND_UP(q_data->width, 16) *
 			DIV_ROUND_UP(q_data->height, 16)) * 3200 / 8 + 512;
@@ -417,7 +406,7 @@ static int coda_alloc_context_buffers(struct coda_ctx *ctx,
 		}
 	}
 
-	if (dev->devtype->product == CODA_7541) {
+	if (!ctx->psbuf.vaddr && dev->devtype->product == CODA_7541) {
 		ret = coda_alloc_context_buf(ctx, &ctx->psbuf,
 					     CODA7_PS_BUF_SIZE, "psbuf");
 		if (ret < 0) {
@@ -427,16 +416,19 @@ static int coda_alloc_context_buffers(struct coda_ctx *ctx,
 		}
 	}
 
-	size = dev->devtype->workbuf_size;
-	if (dev->devtype->product == CODA_960 &&
-	    q_data->fourcc == V4L2_PIX_FMT_H264)
-		size += CODA9_PS_SAVE_SIZE;
-	ret = coda_alloc_context_buf(ctx, &ctx->workbuf, size, "workbuf");
-	if (ret < 0) {
-		v4l2_err(&dev->v4l2_dev,
-			 "failed to allocate %d byte context buffer",
-			 ctx->workbuf.size);
-		goto err;
+	if (!ctx->workbuf.vaddr) {
+		size = dev->devtype->workbuf_size;
+		if (dev->devtype->product == CODA_960 &&
+		    q_data->fourcc == V4L2_PIX_FMT_H264)
+			size += CODA9_PS_SAVE_SIZE;
+		ret = coda_alloc_context_buf(ctx, &ctx->workbuf, size,
+					     "workbuf");
+		if (ret < 0) {
+			v4l2_err(&dev->v4l2_dev,
+				 "failed to allocate %d byte context buffer",
+				 ctx->workbuf.size);
+			goto err;
+		}
 	}
 
 	return 0;
@@ -1337,6 +1329,7 @@ static void coda_bit_release(struct coda_ctx *ctx)
 	mutex_lock(&ctx->buffer_mutex);
 	coda_free_framebuffers(ctx);
 	coda_free_context_buffers(ctx);
+	coda_free_bitstream_buffer(ctx);
 	mutex_unlock(&ctx->buffer_mutex);
 }
 
@@ -1354,6 +1347,38 @@ const struct coda_context_ops coda_bit_encode_ops = {
  * Decoder context operations
  */
 
+static int coda_alloc_bitstream_buffer(struct coda_ctx *ctx,
+				       struct coda_q_data *q_data)
+{
+	if (ctx->bitstream.vaddr)
+		return 0;
+
+	ctx->bitstream.size = roundup_pow_of_two(q_data->sizeimage * 2);
+	ctx->bitstream.vaddr = dma_alloc_writecombine(
+			&ctx->dev->plat_dev->dev, ctx->bitstream.size,
+			&ctx->bitstream.paddr, GFP_KERNEL);
+	if (!ctx->bitstream.vaddr) {
+		v4l2_err(&ctx->dev->v4l2_dev,
+			 "failed to allocate bitstream ringbuffer");
+		return -ENOMEM;
+	}
+	kfifo_init(&ctx->bitstream_fifo,
+		   ctx->bitstream.vaddr, ctx->bitstream.size);
+
+	return 0;
+}
+
+static void coda_free_bitstream_buffer(struct coda_ctx *ctx)
+{
+	if (ctx->bitstream.vaddr == NULL)
+		return;
+
+	dma_free_writecombine(&ctx->dev->plat_dev->dev, ctx->bitstream.size,
+			      ctx->bitstream.vaddr, ctx->bitstream.paddr);
+	ctx->bitstream.vaddr = NULL;
+	kfifo_init(&ctx->bitstream_fifo, NULL, 0);
+}
+
 static int coda_decoder_reqbufs(struct coda_ctx *ctx,
 				struct v4l2_requestbuffers *rb)
 {
@@ -1368,7 +1393,13 @@ static int coda_decoder_reqbufs(struct coda_ctx *ctx,
 		ret = coda_alloc_context_buffers(ctx, q_data_src);
 		if (ret < 0)
 			return ret;
+		ret = coda_alloc_bitstream_buffer(ctx, q_data_src);
+		if (ret < 0) {
+			coda_free_context_buffers(ctx);
+			return ret;
+		}
 	} else {
+		coda_free_bitstream_buffer(ctx);
 		coda_free_context_buffers(ctx);
 	}
 
@@ -1736,7 +1767,7 @@ static void coda_finish_decode(struct coda_ctx *ctx)
 	 * by up to 512 bytes
 	 */
 	if (ctx->bit_stream_param & CODA_BIT_STREAM_END_FLAG) {
-		if (coda_get_bitstream_payload(ctx) >= CODA_MAX_FRAME_SIZE - 512)
+		if (coda_get_bitstream_payload(ctx) >= ctx->bitstream.size - 512)
 			kfifo_init(&ctx->bitstream_fifo,
 				ctx->bitstream.vaddr, ctx->bitstream.size);
 	}

drivers/media/platform/coda/coda-common.c

@@ -1723,20 +1723,6 @@ static int coda_open(struct file *file)
 			goto err_dma_alloc;
 		}
 	}
-	if (ctx->use_bit && ctx->inst_type == CODA_INST_DECODER) {
-		ctx->bitstream.size = CODA_MAX_FRAME_SIZE;
-		ctx->bitstream.vaddr = dma_alloc_writecombine(
-				&dev->plat_dev->dev, ctx->bitstream.size,
-				&ctx->bitstream.paddr, GFP_KERNEL);
-		if (!ctx->bitstream.vaddr) {
-			v4l2_err(&dev->v4l2_dev,
-				 "failed to allocate bitstream ringbuffer");
-			ret = -ENOMEM;
-			goto err_dma_writecombine;
-		}
-	}
-	kfifo_init(&ctx->bitstream_fifo,
-		ctx->bitstream.vaddr, ctx->bitstream.size);
 	mutex_init(&ctx->bitstream_mutex);
 	mutex_init(&ctx->buffer_mutex);
 	INIT_LIST_HEAD(&ctx->buffer_meta_list);
@@ -1750,10 +1736,6 @@ static int coda_open(struct file *file)
 
 	return 0;
 
-err_dma_writecombine:
-	if (ctx->dev->devtype->product == CODA_DX6)
-		coda_free_aux_buf(dev, &ctx->workbuf);
-	coda_free_aux_buf(dev, &ctx->parabuf);
 err_dma_alloc:
 	v4l2_ctrl_handler_free(&ctx->ctrls);
 err_ctrls_setup:
@@ -1798,10 +1780,6 @@ static int coda_release(struct file *file)
 	list_del(&ctx->list);
 	coda_unlock(ctx);
 
-	if (ctx->bitstream.vaddr) {
-		dma_free_writecombine(&dev->plat_dev->dev, ctx->bitstream.size,
-			ctx->bitstream.vaddr, ctx->bitstream.paddr);
-	}
 	if (ctx->dev->devtype->product == CODA_DX6)
 		coda_free_aux_buf(dev, &ctx->workbuf);
 

drivers/media/platform/coda/coda.h

@@ -26,7 +26,6 @@
 #include "coda_regs.h"
 
 #define CODA_MAX_FRAMEBUFFERS	8
-#define CODA_MAX_FRAME_SIZE	0x100000
 #define FMO_SLICE_SAVE_BUF_SIZE	(32)
 
 enum {