| /* |
| * Copyright (c) 2011-2012, The Linux Foundation. All rights reserved. |
| |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following |
| * disclaimer in the documentation and/or other materials provided |
| * with the distribution. |
| * * Neither the name of The Linux Foundation nor the names of its |
| * contributors may be used to endorse or promote products derived |
| * from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS |
| * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
| * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE |
| * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN |
| * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include <cutils/log.h> |
| #include <cutils/native_handle.h> |
| #include <gralloc_priv.h> |
| #include <linux/genlock.h> |
| #include <fcntl.h> |
| #include <sys/ioctl.h> |
| |
| #include "genlock.h" |
| |
| #define GENLOCK_DEVICE "/dev/genlock" |
| |
| namespace { |
| /* Internal function to map the userspace locks to the kernel lock types */ |
| int get_kernel_lock_type(genlock_lock_type lockType) |
| { |
| int kLockType = 0; |
| #ifdef USE_GENLOCK |
| // If the user sets both a read and write lock, higher preference is |
| // given to the write lock. |
| if (lockType & GENLOCK_WRITE_LOCK) { |
| kLockType = GENLOCK_WRLOCK; |
| } else if (lockType & GENLOCK_READ_LOCK) { |
| kLockType = GENLOCK_RDLOCK; |
| } else { |
| ALOGE("%s: invalid lockType (lockType = %d)", |
| __FUNCTION__, lockType); |
| return -1; |
| } |
| #endif |
| return kLockType; |
| } |
| |
| /* Internal function to perform the actual lock/unlock operations */ |
| genlock_status_t perform_lock_unlock_operation(native_handle_t *buffer_handle, |
| int lockType, int timeout, |
| int flags) |
| { |
| #ifdef USE_GENLOCK |
| if (private_handle_t::validate(buffer_handle)) { |
| ALOGE("%s: handle is invalid", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| private_handle_t *hnd = reinterpret_cast<private_handle_t*> |
| (buffer_handle); |
| if ((hnd->flags & private_handle_t::PRIV_FLAGS_UNSYNCHRONIZED) == 0) { |
| if (hnd->genlockPrivFd < 0) { |
| ALOGE("%s: the lock has not been created," |
| "or has not been attached", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| genlock_lock lock; |
| lock.op = lockType; |
| lock.flags = flags; |
| lock.timeout = timeout; |
| lock.fd = hnd->genlockHandle; |
| |
| #ifdef GENLOCK_IOC_DREADLOCK |
| if (ioctl(hnd->genlockPrivFd, GENLOCK_IOC_DREADLOCK, &lock)) { |
| ALOGE("%s: GENLOCK_IOC_DREADLOCK failed (lockType0x%x," |
| "err=%s fd=%d)", __FUNCTION__, |
| lockType, strerror(errno), hnd->fd); |
| if (ETIMEDOUT == errno) |
| return GENLOCK_TIMEDOUT; |
| |
| return GENLOCK_FAILURE; |
| } |
| #else |
| // depreciated |
| if (ioctl(hnd->genlockPrivFd, GENLOCK_IOC_LOCK, &lock)) { |
| ALOGE("%s: GENLOCK_IOC_LOCK failed (lockType0x%x, err=%s fd=%d)" |
| ,__FUNCTION__, lockType, strerror(errno), hnd->fd); |
| if (ETIMEDOUT == errno) |
| return GENLOCK_TIMEDOUT; |
| |
| return GENLOCK_FAILURE; |
| } |
| #endif |
| } |
| #endif |
| return GENLOCK_NO_ERROR; |
| } |
| |
| /* Internal function to close the fd and release the handle */ |
| void close_genlock_fd_and_handle(int& fd, int& handle) |
| { |
| if (fd >=0 ) { |
| close(fd); |
| fd = -1; |
| } |
| |
| if (handle >= 0) { |
| close(handle); |
| handle = -1; |
| } |
| } |
| } |
| /* |
| * Create a genlock lock. The genlock lock file descriptor and the lock |
| * handle are stored in the buffer_handle. |
| * |
| * @param: handle of the buffer |
| * @return error status. |
| */ |
| genlock_status_t genlock_create_lock(native_handle_t *buffer_handle) |
| { |
| genlock_status_t ret = GENLOCK_NO_ERROR; |
| #ifdef USE_GENLOCK |
| if (private_handle_t::validate(buffer_handle)) { |
| ALOGE("%s: handle is invalid", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| private_handle_t *hnd = reinterpret_cast<private_handle_t*>(buffer_handle); |
| if ((hnd->flags & private_handle_t::PRIV_FLAGS_UNSYNCHRONIZED) == 0) { |
| // Open the genlock device |
| int fd = open(GENLOCK_DEVICE, O_RDWR); |
| if (fd < 0) { |
| ALOGE("%s: open genlock device failed (err=%s)", __FUNCTION__, |
| strerror(errno)); |
| return GENLOCK_FAILURE; |
| } |
| |
| // Create a new lock |
| genlock_lock lock; |
| if (ioctl(fd, GENLOCK_IOC_NEW, NULL)) { |
| ALOGE("%s: GENLOCK_IOC_NEW failed (error=%s)", __FUNCTION__, |
| strerror(errno)); |
| close_genlock_fd_and_handle(fd, lock.fd); |
| ret = GENLOCK_FAILURE; |
| } |
| |
| // Export the lock for other processes to be able to use it. |
| if (GENLOCK_FAILURE != ret) { |
| if (ioctl(fd, GENLOCK_IOC_EXPORT, &lock)) { |
| ALOGE("%s: GENLOCK_IOC_EXPORT failed (error=%s)", __FUNCTION__, |
| strerror(errno)); |
| close_genlock_fd_and_handle(fd, lock.fd); |
| ret = GENLOCK_FAILURE; |
| } |
| } |
| |
| // Store the lock params in the handle. |
| hnd->genlockPrivFd = fd; |
| hnd->genlockHandle = lock.fd; |
| } else { |
| hnd->genlockHandle = 0; |
| } |
| #endif |
| return ret; |
| } |
| |
| |
| /* |
| * Release a genlock lock associated with the handle. |
| * |
| * @param: handle of the buffer |
| * @return error status. |
| */ |
| genlock_status_t genlock_release_lock(native_handle_t *buffer_handle) |
| { |
| genlock_status_t ret = GENLOCK_NO_ERROR; |
| #ifdef USE_GENLOCK |
| if (private_handle_t::validate(buffer_handle)) { |
| ALOGE("%s: handle is invalid", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| private_handle_t *hnd = reinterpret_cast<private_handle_t*>(buffer_handle); |
| if ((hnd->flags & private_handle_t::PRIV_FLAGS_UNSYNCHRONIZED) == 0) { |
| if (hnd->genlockPrivFd < 0) { |
| ALOGE("%s: the lock is invalid", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| // Close the fd and reset the parameters. |
| close_genlock_fd_and_handle(hnd->genlockPrivFd, hnd->genlockHandle); |
| } |
| #endif |
| return ret; |
| } |
| |
| |
| /* |
| * Attach a lock to the buffer handle passed via an IPC. |
| * |
| * @param: handle of the buffer |
| * @return error status. |
| */ |
| genlock_status_t genlock_attach_lock(native_handle_t *buffer_handle) |
| { |
| genlock_status_t ret = GENLOCK_NO_ERROR; |
| #ifdef USE_GENLOCK |
| if (private_handle_t::validate(buffer_handle)) { |
| ALOGE("%s: handle is invalid", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| private_handle_t *hnd = reinterpret_cast<private_handle_t*>(buffer_handle); |
| if ((hnd->flags & private_handle_t::PRIV_FLAGS_UNSYNCHRONIZED) == 0) { |
| // Open the genlock device |
| int fd = open(GENLOCK_DEVICE, O_RDWR); |
| if (fd < 0) { |
| ALOGE("%s: open genlock device failed (err=%s)", __FUNCTION__, |
| strerror(errno)); |
| return GENLOCK_FAILURE; |
| } |
| |
| // Attach the local handle to an existing lock |
| genlock_lock lock; |
| lock.fd = hnd->genlockHandle; |
| if (ioctl(fd, GENLOCK_IOC_ATTACH, &lock)) { |
| ALOGE("%s: GENLOCK_IOC_ATTACH failed (err=%s)", __FUNCTION__, |
| strerror(errno)); |
| close_genlock_fd_and_handle(fd, lock.fd); |
| ret = GENLOCK_FAILURE; |
| } |
| |
| // Store the relavant information in the handle |
| hnd->genlockPrivFd = fd; |
| } |
| #endif |
| return ret; |
| } |
| |
| /* |
| * Lock the buffer specified by the buffer handle. The lock held by the buffer |
| * is specified by the lockType. This function will block if a write lock is |
| * requested on the buffer which has previously been locked for a read or write |
| * operation. A buffer can be locked by multiple clients for read. An optional |
| * timeout value can be specified. By default, there is no timeout. |
| * |
| * @param: handle of the buffer |
| * @param: type of lock to be acquired by the buffer. |
| * @param: timeout value in ms. GENLOCK_MAX_TIMEOUT is the maximum timeout value. |
| * @return error status. |
| */ |
| genlock_status_t genlock_lock_buffer(native_handle_t *buffer_handle, |
| genlock_lock_type_t lockType, |
| int timeout) |
| { |
| genlock_status_t ret = GENLOCK_NO_ERROR; |
| #ifdef USE_GENLOCK |
| // Translate the locktype |
| int kLockType = get_kernel_lock_type(lockType); |
| if (-1 == kLockType) { |
| ALOGE("%s: invalid lockType", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| if (0 == timeout) { |
| ALOGW("%s: trying to lock a buffer with timeout = 0", __FUNCTION__); |
| } |
| // Call the private function to perform the lock operation specified. |
| ret = perform_lock_unlock_operation(buffer_handle, kLockType, timeout, 0); |
| #endif |
| return ret; |
| } |
| |
| |
| /* |
| * Unlocks a buffer that has previously been locked by the client. |
| * |
| * @param: handle of the buffer to be unlocked. |
| * @return: error status. |
| */ |
| genlock_status_t genlock_unlock_buffer(native_handle_t *buffer_handle) |
| { |
| genlock_status_t ret = GENLOCK_NO_ERROR; |
| #ifdef USE_GENLOCK |
| // Do the unlock operation by setting the unlock flag. Timeout is always |
| // 0 in this case. |
| ret = perform_lock_unlock_operation(buffer_handle, GENLOCK_UNLOCK, 0, 0); |
| #endif |
| return ret; |
| } |
| |
| /* |
| * Blocks the calling process until the lock held on the handle is unlocked. |
| * |
| * @param: handle of the buffer |
| * @param: timeout value for the wait. |
| * return: error status. |
| */ |
| genlock_status_t genlock_wait(native_handle_t *buffer_handle, int timeout) { |
| #ifdef USE_GENLOCK |
| if (private_handle_t::validate(buffer_handle)) { |
| ALOGE("%s: handle is invalid", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| private_handle_t *hnd = reinterpret_cast<private_handle_t*>(buffer_handle); |
| if ((hnd->flags & private_handle_t::PRIV_FLAGS_UNSYNCHRONIZED) == 0) { |
| if (hnd->genlockPrivFd < 0) { |
| ALOGE("%s: the lock is invalid", __FUNCTION__); |
| return GENLOCK_FAILURE; |
| } |
| |
| if (0 == timeout) |
| ALOGW("%s: timeout = 0", __FUNCTION__); |
| |
| genlock_lock lock; |
| lock.fd = hnd->genlockHandle; |
| lock.timeout = timeout; |
| if (ioctl(hnd->genlockPrivFd, GENLOCK_IOC_WAIT, &lock)) { |
| ALOGE("%s: GENLOCK_IOC_WAIT failed (err=%s)", __FUNCTION__, |
| strerror(errno)); |
| return GENLOCK_FAILURE; |
| } |
| } |
| #endif |
| return GENLOCK_NO_ERROR; |
| } |
| |
| /* |
| * Convert a write lock that we own to a read lock |
| * |
| * @param: handle of the buffer |
| * @param: timeout value for the wait. |
| * return: error status. |
| */ |
| genlock_status_t genlock_write_to_read(native_handle_t *buffer_handle, |
| int timeout) { |
| genlock_status_t ret = GENLOCK_NO_ERROR; |
| #ifdef USE_GENLOCK |
| if (0 == timeout) { |
| ALOGW("%s: trying to lock a buffer with timeout = 0", __FUNCTION__); |
| } |
| // Call the private function to perform the lock operation specified. |
| #ifdef GENLOCK_IOC_DREADLOCK |
| ret = perform_lock_unlock_operation(buffer_handle, GENLOCK_RDLOCK, timeout, |
| GENLOCK_WRITE_TO_READ); |
| #else |
| // depreciated |
| ret = perform_lock_unlock_operation(buffer_handle, GENLOCK_RDLOCK, |
| timeout, 0); |
| #endif |
| #endif |
| return ret; |
| } |