camerad: auto free the buffer when it goes out of scope (#28807)

old-commit-hash: 8076107b4f

system/camerad/cameras/camera_qcom2.cc

@@ -143,7 +143,7 @@ void CameraState::sensors_start() {
 void CameraState::sensors_poke(int request_id) {
   uint32_t cam_packet_handle = 0;
   int size = sizeof(struct cam_packet);
-  struct cam_packet *pkt = (struct cam_packet *)mm.alloc(size, &cam_packet_handle);
+  auto pkt = mm.alloc<struct cam_packet>(size, &cam_packet_handle);
   pkt->num_cmd_buf = 0;
   pkt->kmd_cmd_buf_index = -1;
   pkt->header.size = size;
@@ -156,15 +156,13 @@ void CameraState::sensors_poke(int request_id) {
     enabled = false;
     return;
   }
-
-  mm.free(pkt);
 }
 
 void CameraState::sensors_i2c(struct i2c_random_wr_payload* dat, int len, int op_code, bool data_word) {
   // LOGD("sensors_i2c: %d", len);
   uint32_t cam_packet_handle = 0;
   int size = sizeof(struct cam_packet)+sizeof(struct cam_cmd_buf_desc)*1;
-  struct cam_packet *pkt = (struct cam_packet *)mm.alloc(size, &cam_packet_handle);
+  auto pkt = mm.alloc<struct cam_packet>(size, &cam_packet_handle);
   pkt->num_cmd_buf = 1;
   pkt->kmd_cmd_buf_index = -1;
   pkt->header.size = size;
@@ -174,7 +172,7 @@ void CameraState::sensors_i2c(struct i2c_random_wr_payload* dat, int len, int op
   buf_desc[0].size = buf_desc[0].length = sizeof(struct i2c_rdwr_header) + len*sizeof(struct i2c_random_wr_payload);
   buf_desc[0].type = CAM_CMD_BUF_I2C;
 
-  struct cam_cmd_i2c_random_wr *i2c_random_wr = (struct cam_cmd_i2c_random_wr *)mm.alloc(buf_desc[0].size, (uint32_t*)&buf_desc[0].mem_handle);
+  auto i2c_random_wr = mm.alloc<struct cam_cmd_i2c_random_wr>(buf_desc[0].size, (uint32_t*)&buf_desc[0].mem_handle);
   i2c_random_wr->header.count = len;
   i2c_random_wr->header.op_code = 1;
   i2c_random_wr->header.cmd_type = CAMERA_SENSOR_CMD_TYPE_I2C_RNDM_WR;
@@ -188,9 +186,6 @@ void CameraState::sensors_i2c(struct i2c_random_wr_payload* dat, int len, int op
     enabled = false;
     return;
   }
-
-  mm.free(i2c_random_wr);
-  mm.free(pkt);
 }
 
 static cam_cmd_power *power_set_wait(cam_cmd_power *power, int16_t delay_ms) {
@@ -204,7 +199,7 @@ static cam_cmd_power *power_set_wait(cam_cmd_power *power, int16_t delay_ms) {
 int CameraState::sensors_init() {
   uint32_t cam_packet_handle = 0;
   int size = sizeof(struct cam_packet)+sizeof(struct cam_cmd_buf_desc)*2;
-  struct cam_packet *pkt = (struct cam_packet *)mm.alloc(size, &cam_packet_handle);
+  auto pkt = mm.alloc<struct cam_packet>(size, &cam_packet_handle);
   pkt->num_cmd_buf = 2;
   pkt->kmd_cmd_buf_index = -1;
   pkt->header.op_code = 0x1000000 | CAM_SENSOR_PACKET_OPCODE_SENSOR_PROBE;
@@ -213,8 +208,8 @@ int CameraState::sensors_init() {
 
   buf_desc[0].size = buf_desc[0].length = sizeof(struct cam_cmd_i2c_info) + sizeof(struct cam_cmd_probe);
   buf_desc[0].type = CAM_CMD_BUF_LEGACY;
-  struct cam_cmd_i2c_info *i2c_info = (struct cam_cmd_i2c_info *)mm.alloc(buf_desc[0].size, (uint32_t*)&buf_desc[0].mem_handle);
+  auto i2c_info = mm.alloc<struct cam_cmd_i2c_info>(buf_desc[0].size, (uint32_t*)&buf_desc[0].mem_handle);
-  auto probe = (struct cam_cmd_probe *)(i2c_info + 1);
+  auto probe = (struct cam_cmd_probe *)(i2c_info.get() + 1);
 
   probe->camera_id = camera_num;
   switch (camera_num) {
@@ -255,11 +250,11 @@ int CameraState::sensors_init() {
   //buf_desc[1].size = buf_desc[1].length = 148;
   buf_desc[1].size = buf_desc[1].length = 196;
   buf_desc[1].type = CAM_CMD_BUF_I2C;
-  struct cam_cmd_power *power_settings = (struct cam_cmd_power *)mm.alloc(buf_desc[1].size, (uint32_t*)&buf_desc[1].mem_handle);
+  auto power_settings = mm.alloc<struct cam_cmd_power>(buf_desc[1].size, (uint32_t*)&buf_desc[1].mem_handle);
-  memset(power_settings, 0, buf_desc[1].size);
+  memset(power_settings.get(), 0, buf_desc[1].size);
 
   // power on
-  struct cam_cmd_power *power = power_settings;
+  struct cam_cmd_power *power = power_settings.get();
   power->count = 4;
   power->cmd_type = CAMERA_SENSOR_CMD_TYPE_PWR_UP;
   power->power_settings[0].power_seq_type = 3; // clock??
@@ -315,11 +310,6 @@ int CameraState::sensors_init() {
 
   int ret = do_cam_control(sensor_fd, CAM_SENSOR_PROBE_CMD, (void *)(uintptr_t)cam_packet_handle, 0);
   LOGD("probing the sensor: %d", ret);
-
-  mm.free(i2c_info);
-  mm.free(power_settings);
-  mm.free(pkt);
-
   return ret;
 }
 
@@ -329,7 +319,7 @@ void CameraState::config_isp(int io_mem_handle, int fence, int request_id, int b
   if (io_mem_handle != 0) {
     size += sizeof(struct cam_buf_io_cfg);
   }
-  struct cam_packet *pkt = (struct cam_packet *)mm.alloc(size, &cam_packet_handle);
+  auto pkt = mm.alloc<struct cam_packet>(size, &cam_packet_handle);
   pkt->num_cmd_buf = 2;
   pkt->kmd_cmd_buf_index = 0;
   // YUV has kmd_cmd_buf_offset = 1780
@@ -424,8 +414,8 @@ void CameraState::config_isp(int io_mem_handle, int fence, int request_id, int b
   buf_desc[1].length = buf_desc[1].size - buf_desc[1].offset;
   buf_desc[1].type = CAM_CMD_BUF_GENERIC;
   buf_desc[1].meta_data = CAM_ISP_PACKET_META_GENERIC_BLOB_COMMON;
-  uint32_t *buf2 = (uint32_t *)mm.alloc(buf_desc[1].size, (uint32_t*)&buf_desc[1].mem_handle);
+  auto buf2 = mm.alloc<uint32_t>(buf_desc[1].size, (uint32_t*)&buf_desc[1].mem_handle);
-  memcpy(buf2, &tmp, sizeof(tmp));
+  memcpy(buf2.get(), &tmp, sizeof(tmp));
 
   if (io_mem_handle != 0) {
     io_cfg[0].mem_handle[0] = io_mem_handle;
@@ -459,9 +449,6 @@ void CameraState::config_isp(int io_mem_handle, int fence, int request_id, int b
   if (ret != 0) {
     LOGE("isp config failed");
   }
-
-  mm.free(buf2);
-  mm.free(pkt);
 }
 
 void CameraState::enqueue_buffer(int i, bool dp) {
@@ -746,7 +733,7 @@ void CameraState::camera_open(MultiCameraState *multi_cam_state_, int camera_num
   {
     uint32_t cam_packet_handle = 0;
     int size = sizeof(struct cam_packet)+sizeof(struct cam_cmd_buf_desc)*1;
-    struct cam_packet *pkt = (struct cam_packet *)mm.alloc(size, &cam_packet_handle);
+    auto pkt = mm.alloc<struct cam_packet>(size, &cam_packet_handle);
     pkt->num_cmd_buf = 1;
     pkt->kmd_cmd_buf_index = -1;
     pkt->header.size = size;
@@ -755,7 +742,7 @@ void CameraState::camera_open(MultiCameraState *multi_cam_state_, int camera_num
     buf_desc[0].size = buf_desc[0].length = sizeof(struct cam_csiphy_info);
     buf_desc[0].type = CAM_CMD_BUF_GENERIC;
 
-    struct cam_csiphy_info *csiphy_info = (struct cam_csiphy_info *)mm.alloc(buf_desc[0].size, (uint32_t*)&buf_desc[0].mem_handle);
+    auto csiphy_info = mm.alloc<struct cam_csiphy_info>(buf_desc[0].size, (uint32_t*)&buf_desc[0].mem_handle);
     csiphy_info->lane_mask = 0x1f;
     csiphy_info->lane_assign = 0x3210;// skip clk. How is this 16 bit for 5 channels??
     csiphy_info->csiphy_3phase = 0x0; // no 3 phase, only 2 conductors per lane
@@ -767,9 +754,6 @@ void CameraState::camera_open(MultiCameraState *multi_cam_state_, int camera_num
 
     int ret_ = device_config(csiphy_fd, session_handle, csiphy_dev_handle, cam_packet_handle);
     assert(ret_ == 0);
-
-    mm.free(csiphy_info);
-    mm.free(pkt);
   }
 
   // link devices

system/camerad/cameras/camera_util.cc

@@ -98,7 +98,7 @@ void release_fd(int video0_fd, uint32_t handle) {
   release(video0_fd, handle);
 }
 
-void *MemoryManager::alloc(int size, uint32_t *handle) {
+void *MemoryManager::alloc_buf(int size, uint32_t *handle) {
   lock.lock();
   void *ptr;
   if (!cached_allocations[size].empty()) {

system/camerad/cameras/camera_util.h

@@ -1,6 +1,8 @@
 #pragma once
 
+ #include <functional>
 #include <map>
+#include <memory>
 #include <mutex>
 #include <optional>
 #include <queue>
@@ -18,10 +20,17 @@ void release(int video0_fd, uint32_t handle);
 class MemoryManager {
   public:
     void init(int _video0_fd) { video0_fd = _video0_fd; }
-    void *alloc(int len, uint32_t *handle);
-    void free(void *ptr);
     ~MemoryManager();
+
+    template <class T>
+    auto alloc(int len, uint32_t *handle) {
+      return std::unique_ptr<T, std::function<void(void *)>>((T*)alloc_buf(len, handle), [this](void *ptr) { this->free(ptr); });
+    }
+
   private:
+    void *alloc_buf(int len, uint32_t *handle);
+    void free(void *ptr);
+
     std::mutex lock;
     std::map<void *, uint32_t> handle_lookup;
     std::map<void *, int> size_lookup;