[libcamera-devel] [RFC PATCH v2 05/10] ipa: rkisp1: Use offset in mapping IPABuffer

[Hirokazu Honda]

IPABuffer is represented by FrameBuffer. FrameBuffer::Plane has
now an offset. This uses the offset variable to map the IPABuffer.

Signed-off-by: Hirokazu Honda <hiroh at chromium.org>
---
 .../libcamera/internal/mapped_framebuffer.h   |  1 +
 src/ipa/rkisp1/rkisp1.cpp                     | 31 +++++++------------
 src/libcamera/mapped_framebuffer.cpp          |  7 +++++
 3 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/include/libcamera/internal/mapped_framebuffer.h b/include/libcamera/internal/mapped_framebuffer.h
index 42479541..ee0583d0 100644
--- a/include/libcamera/internal/mapped_framebuffer.h
+++ b/include/libcamera/internal/mapped_framebuffer.h
@@ -55,6 +55,7 @@ public:
 
 	using MapFlags = Flags<MapFlag>;
 
+	MappedFrameBuffer();
 	MappedFrameBuffer(const FrameBuffer *buffer, MapFlags flags);
 };
 
diff --git a/src/ipa/rkisp1/rkisp1.cpp b/src/ipa/rkisp1/rkisp1.cpp
index 06fb9640..54cf2885 100644
--- a/src/ipa/rkisp1/rkisp1.cpp
+++ b/src/ipa/rkisp1/rkisp1.cpp
@@ -10,7 +10,6 @@
 #include <queue>
 #include <stdint.h>
 #include <string.h>
-#include <sys/mman.h>
 
 #include <linux/rkisp1-config.h>
 #include <linux/v4l2-controls.h>
@@ -24,6 +23,8 @@
 #include <libcamera/ipa/rkisp1_ipa_interface.h>
 #include <libcamera/request.h>
 
+#include <libcamera/internal/mapped_framebuffer.h>
+
 namespace libcamera {
 
 LOG_DEFINE_CATEGORY(IPARkISP1)
@@ -54,7 +55,7 @@ private:
 	void metadataReady(unsigned int frame, unsigned int aeState);
 
 	std::map<unsigned int, FrameBuffer> buffers_;
-	std::map<unsigned int, void *> buffersMemory_;
+	std::map<unsigned int, MappedFrameBuffer> mappedBuffers_;
 
 	ControlInfoMap ctrls_;
 
@@ -160,21 +161,10 @@ void IPARkISP1::mapBuffers(const std::vector<IPABuffer> &buffers)
 					     std::forward_as_tuple(buffer.planes));
 		const FrameBuffer &fb = elem.first->second;
 
-		/*
-		 * \todo Provide a helper to mmap() buffers (possibly exposed
-		 * to applications).
-		 */
-		buffersMemory_[buffer.id] = mmap(NULL,
-						 fb.planes()[0].length,
-						 PROT_READ | PROT_WRITE,
-						 MAP_SHARED,
-						 fb.planes()[0].fd.fd(),
-						 0);
-
-		if (buffersMemory_[buffer.id] == MAP_FAILED) {
-			int ret = -errno;
+		mappedBuffers_[buffer.id] = MappedFrameBuffer(&fb, MappedFrameBuffer::MapFlag::ReadWrite);
+		if (!mappedBuffers_[buffer.id].isValid()) {
 			LOG(IPARkISP1, Fatal) << "Failed to mmap buffer: "
-					      << strerror(-ret);
+					      << strerror(mappedBuffers_[buffer.id].error());
 		}
 	}
 }
@@ -186,8 +176,7 @@ void IPARkISP1::unmapBuffers(const std::vector<unsigned int> &ids)
 		if (fb == buffers_.end())
 			continue;
 
-		munmap(buffersMemory_[id], fb->second.planes()[0].length);
-		buffersMemory_.erase(id);
+		mappedBuffers_.erase(id);
 		buffers_.erase(id);
 	}
 }
@@ -200,7 +189,8 @@ void IPARkISP1::processEvent(const RkISP1Event &event)
 		unsigned int bufferId = event.bufferId;
 
 		const rkisp1_stat_buffer *stats =
-			static_cast<rkisp1_stat_buffer *>(buffersMemory_[bufferId]);
+			reinterpret_cast<rkisp1_stat_buffer *>(
+				mappedBuffers_[bufferId].maps()[0].data());
 
 		updateStatistics(frame, stats);
 		break;
@@ -210,7 +200,8 @@ void IPARkISP1::processEvent(const RkISP1Event &event)
 		unsigned int bufferId = event.bufferId;
 
 		rkisp1_params_cfg *params =
-			static_cast<rkisp1_params_cfg *>(buffersMemory_[bufferId]);
+			reinterpret_cast<rkisp1_params_cfg *>(
+				mappedBuffers_[bufferId].maps()[0].data());
 
 		queueRequest(frame, params, event.controls);
 		break;
diff --git a/src/libcamera/mapped_framebuffer.cpp b/src/libcamera/mapped_framebuffer.cpp
index 03425dea..34d9564d 100644
--- a/src/libcamera/mapped_framebuffer.cpp
+++ b/src/libcamera/mapped_framebuffer.cpp
@@ -168,6 +168,13 @@ MappedBuffer::~MappedBuffer()
  * \brief A bitwise combination of MappedFrameBuffer::MapFlag values
  */
 
+/**
+ * \brief Construct an empty MappedFrameBuffer
+ */
+MappedFrameBuffer::MappedFrameBuffer()
+	: MappedBuffer()
+{
+}
 /**
  * \brief Map all planes of a FrameBuffer
  * \param[in] buffer FrameBuffer to be mapped
-- 
2.33.0.rc2.250.ged5fa647cd-goog