X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=os%2Fos-android.h;h=f371116f8f6a9a45a37372b3044f71c77f88f368;hp=6c3e0985b22fc5896e21d42458f02ff4b2be444c;hb=d87674757a6afddc059e5bbfae3fcf267236a44e;hpb=4641daa9b2e33bc63197dfec48584eaf05890a01

diff --git a/os/os-android.h b/os/os-android.h
index 6c3e0985..f371116f 100644
--- a/os/os-android.h
+++ b/os/os-android.h
@@ -98,7 +98,8 @@ static inline int shmget (key_t __key, size_t __size, int __shmflg)
 	if (ret < 0)
 		goto error;
 
-	ret = ioctl(fd, ASHMEM_SET_SIZE, __size);
+	/* Stores size in first 8 bytes, allocate extra space */
+	ret = ioctl(fd, ASHMEM_SET_SIZE, __size + sizeof(uint64_t));
 	if (ret < 0)
 		goto error;
 
@@ -111,19 +112,20 @@ error:
 
 static inline void *shmat (int __shmid, const void *__shmaddr, int __shmflg)
 {
-	size_t *ptr, size = ioctl(__shmid, ASHMEM_GET_SIZE, NULL);
-	ptr = mmap(NULL, size + sizeof(size_t), PROT_READ | PROT_WRITE, MAP_SHARED, __shmid, 0);
-	*ptr = size;    //save size at beginning of buffer, for use with munmap
-	return &ptr[1];
+	size_t size = ioctl(__shmid, ASHMEM_GET_SIZE, NULL);
+	/* Needs to be 8-byte aligned to prevent SIGBUS on 32-bit ARM */
+	uint64_t *ptr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, __shmid, 0);
+	/* Save size at beginning of buffer, for use with munmap */
+	*ptr = size;
+	return ptr + 1;
 }
 
 static inline int shmdt (const void *__shmaddr)
 {
-	size_t *ptr, size;
-	ptr = (size_t *)__shmaddr;
-	ptr--;
-	size = *ptr;    //find mmap size which we stored at the beginning of the buffer
-	return munmap((void *)ptr, size + sizeof(size_t));
+	/* Find mmap size which we stored at the beginning of the buffer */
+	uint64_t *ptr = (uint64_t *)__shmaddr - 1;
+	size_t size = *ptr;
+	return munmap(ptr, size);
 }
 #endif