Merge changes from topic "remove_ashmemd" (f0d17fb5) · Commits · e / os / android_system_core

init/devices.cpp

+21 −0

Original line number	Diff line number	Diff line
		@@ -441,6 +441,23 @@ void DeviceHandler::HandleDevice(const std::string& action, const std::string& d
		}
		}

		void DeviceHandler::HandleAshmemUevent(const Uevent& uevent) {
		if (uevent.device_name == "ashmem") {
		static const std::string boot_id_path = "/proc/sys/kernel/random/boot_id";
		std::string boot_id;
		if (!ReadFileToString(boot_id_path, &boot_id)) {
		PLOG(ERROR) << "Cannot duplicate ashmem device node. Failed to read " << boot_id_path;
		return;
		};
		boot_id = Trim(boot_id);

		Uevent dup_ashmem_uevent = uevent;
		dup_ashmem_uevent.device_name += boot_id;
		dup_ashmem_uevent.path += boot_id;
		HandleUevent(dup_ashmem_uevent);
		}
		}

		void DeviceHandler::HandleUevent(const Uevent& uevent) {
		if (uevent.action == "add" \|\| uevent.action == "change" \|\| uevent.action == "online") {
		FixupSysPermissions(uevent.path, uevent.subsystem);
		@@ -485,6 +502,10 @@ void DeviceHandler::HandleUevent(const Uevent& uevent) {
		mkdir_recursive(Dirname(devpath), 0755);

		HandleDevice(uevent.action, devpath, block, uevent.major, uevent.minor, links);

		// Duplicate /dev/ashmem device and name it /dev/ashmem<boot_id>.
		// TODO(b/111903542): remove once all users of /dev/ashmem are migrated to libcutils API.
		HandleAshmemUevent(uevent);
		}

		void DeviceHandler::ColdbootDone() {

init/devices.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -130,6 +130,7 @@ class DeviceHandler : public UeventHandler {
		void HandleDevice(const std::string& action, const std::string& devpath, bool block, int major,
		int minor, const std::vector<std::string>& links) const;
		void FixupSysPermissions(const std::string& upath, const std::string& subsystem) const;
		void HandleAshmemUevent(const Uevent& uevent);

		std::vector<Permissions> dev_permissions_;
		std::vector<SysfsPermissions> sysfs_permissions_;

libcutils/ashmem-dev.cpp

+19 −50

Original line number	Diff line number	Diff line
		@@ -23,9 +23,6 @@
		*/
		#define LOG_TAG "ashmem"

		#ifndef __ANDROID_VNDK__
		#include <dlfcn.h>
		#endif
		#include <errno.h>
		#include <fcntl.h>
		#include <linux/ashmem.h>
		@@ -42,11 +39,11 @@
		#include <sys/types.h>
		#include <unistd.h>

		#include <android-base/file.h>
		#include <android-base/properties.h>
		#include <android-base/strings.h>
		#include <android-base/unique_fd.h>

		#define ASHMEM_DEVICE "/dev/ashmem"

		/* Will be added to UAPI once upstream change is merged */
		#define F_SEAL_FUTURE_WRITE 0x0010

		@@ -65,32 +62,6 @@ static dev_t __ashmem_rdev;
		*/
		static pthread_mutex_t __ashmem_lock = PTHREAD_MUTEX_INITIALIZER;

		/*
		* We use ashmemd to enforce that apps don't open /dev/ashmem directly. Vendor
		* code can't access system aidl services per Treble requirements. So we limit
		* ashmemd access to the system variant of libcutils.
		*/
		#ifndef __ANDROID_VNDK__
		using openFdType = int (*)();

		static openFdType openFd;

		openFdType initOpenAshmemFd() {
		openFdType openFd = nullptr;
		void* handle = dlopen("libashmemd_client.so", RTLD_NOW);
		if (!handle) {
		ALOGE("Failed to dlopen() libashmemd_client.so: %s", dlerror());
		return openFd;
		}

		openFd = reinterpret_cast<openFdType>(dlsym(handle, "openAshmemdFd"));
		if (!openFd) {
		ALOGE("Failed to dlsym() openAshmemdFd() function: %s", dlerror());
		}
		return openFd;
		}
		#endif

		/*
		* has_memfd_support() determines if the device can use memfd. memfd support
		* has been there for long time, but certain things in it may be missing. We
		@@ -215,25 +186,31 @@ static bool has_memfd_support() {
		return memfd_supported;
		}

		static std::string get_ashmem_device_path() {
		static const std::string boot_id_path = "/proc/sys/kernel/random/boot_id";
		std::string boot_id;
		if (!android::base::ReadFileToString(boot_id_path, &boot_id)) {
		ALOGE("Failed to read %s: %s.\n", boot_id_path.c_str(), strerror(errno));
		return "";
		};
		boot_id = android::base::Trim(boot_id);

		return "/dev/ashmem" + boot_id;
		}

		/* logistics of getting file descriptor for ashmem */
		static int __ashmem_open_locked()
		{
		static const std::string ashmem_device_path = get_ashmem_device_path();

		int ret;
		struct stat st;

		int fd = -1;
		#ifndef __ANDROID_VNDK__
		if (!openFd) {
		openFd = initOpenAshmemFd();
		if (ashmem_device_path.empty()) {
		return -1;
		}

		if (openFd) {
		fd = openFd();
		}
		#endif
		if (fd < 0) {
		fd = TEMP_FAILURE_RETRY(open(ASHMEM_DEVICE, O_RDWR \| O_CLOEXEC));
		}
		int fd = TEMP_FAILURE_RETRY(open(ashmem_device_path.c_str(), O_RDWR \| O_CLOEXEC));
		if (fd < 0) {
		return fd;
		}
		@@ -485,11 +462,3 @@ int ashmem_get_size_region(int fd)

		return __ashmem_check_failure(fd, TEMP_FAILURE_RETRY(ioctl(fd, ASHMEM_GET_SIZE, NULL)));
		}

		void ashmem_init() {
		#ifndef __ANDROID_VNDK__
		pthread_mutex_lock(&__ashmem_lock);
		openFd = initOpenAshmemFd();
		pthread_mutex_unlock(&__ashmem_lock);
		#endif //__ANDROID_VNDK__
		}

libcutils/ashmem-host.cpp

+0 −2

Original line number	Diff line number	Diff line
		@@ -94,5 +94,3 @@ int ashmem_get_size_region(int fd)

		return buf.st_size;
		}

		void ashmem_init() {}

libcutils/include/cutils/ashmem.h

+0 −1

Original line number	Diff line number	Diff line
		@@ -26,7 +26,6 @@ int ashmem_set_prot_region(int fd, int prot);
		int ashmem_pin_region(int fd, size_t offset, size_t len);
		int ashmem_unpin_region(int fd, size_t offset, size_t len);
		int ashmem_get_size_region(int fd);
		void ashmem_init();

		#ifdef __cplusplus
		}