libion: Adapt to new ION interface

4.12+ kernels have substantially different ION interface. Adapt
libion to the new one.

In doing so, for sake of clarity, rename ION_IOC_ALLOC to
ION_IOC_NEW_ALLOC the to denote new mechanism.

An ion_is_legacy() is provided to check whether the kernel supports old
ION interface or new. Userspace has the responsibility to use it
accordingly.

Devices using kernels without the 4.12 ION updates, can continue to use libion
as before, and will have no impact.

Only devices using libion with 4.12+ kernels (or kernels with backported ION
updates) will need to update their users of libion, including gralloc.

Test: validated with hikey gralloc, with both old and new kernels

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
  [sumits: keep old abi compatibility]

Change-Id: I7899af9e812d0cf5e73b443a3f0248118b42a382

2 files changed, 109 insertions, 58 deletions

diff --git a/libion/include/ion/ion.h b/libion/include/ion/ion.h
index f47793d27..a60d24eaf 100644
--- a/libion/include/ion/ion.h
+++ b/libion/include/ion/ion.h
@@ -41,6 +41,15 @@ int ion_map(int fd, ion_user_handle_t handle, size_t length, int prot,
 int ion_share(int fd, ion_user_handle_t handle, int *share_fd);
 int ion_import(int fd, int share_fd, ion_user_handle_t *handle);
 
+/**
+  * Add 4.12+ kernel ION interfaces here for forward compatibility
+  * This should be needed till the pre-4.12+ ION interfaces are backported.
+  */
+int ion_query_heap_cnt(int fd, int* cnt);
+int ion_query_get_heaps(int fd, int cnt, void* buffers);
+
+int ion_is_legacy(int fd);
+
 __END_DECLS
 
 #endif /* __SYS_CORE_ION_H */
diff --git a/libion/ion.c b/libion/ion.c
index 9aaa6f28e..583612854 100644
--- a/libion/ion.c
+++ b/libion/ion.c
@@ -22,6 +22,7 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <linux/ion.h>
+#include <stdatomic.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/ioctl.h>
@@ -30,81 +31,89 @@
 #include <unistd.h>
 
 #include <ion/ion.h>
+#include "ion_4.12.h"
+
 #include <log/log.h>
 
-int ion_open()
-{
+enum ion_version { ION_VERSION_UNKNOWN, ION_VERSION_MODERN, ION_VERSION_LEGACY };
+
+static atomic_int g_ion_version = ATOMIC_VAR_INIT(ION_VERSION_UNKNOWN);
+
+int ion_is_legacy(int fd) {
+    int version = atomic_load_explicit(&g_ion_version, memory_order_acquire);
+    if (version == ION_VERSION_UNKNOWN) {
+        /**
+          * Check for FREE IOCTL here; it is available only in the old
+          * kernels, not the new ones.
+          */
+        int err = ion_free(fd, (ion_user_handle_t)NULL);
+        version = (err == -ENOTTY) ? ION_VERSION_MODERN : ION_VERSION_LEGACY;
+        atomic_store_explicit(&g_ion_version, version, memory_order_release);
+    }
+    return version == ION_VERSION_LEGACY;
+}
+
+int ion_open() {
     int fd = open("/dev/ion", O_RDONLY | O_CLOEXEC);
-    if (fd < 0)
-        ALOGE("open /dev/ion failed!\n");
+    if (fd < 0) ALOGE("open /dev/ion failed!\n");
+
     return fd;
 }
 
-int ion_close(int fd)
-{
+int ion_close(int fd) {
     int ret = close(fd);
-    if (ret < 0)
-        return -errno;
+    if (ret < 0) return -errno;
     return ret;
 }
 
-static int ion_ioctl(int fd, int req, void *arg)
-{
+static int ion_ioctl(int fd, int req, void* arg) {
     int ret = ioctl(fd, req, arg);
     if (ret < 0) {
-        ALOGE("ioctl %x failed with code %d: %s\n", req,
-              ret, strerror(errno));
+        ALOGE("ioctl %x failed with code %d: %s\n", req, ret, strerror(errno));
         return -errno;
     }
     return ret;
 }
 
-int ion_alloc(int fd, size_t len, size_t align, unsigned int heap_mask,
-              unsigned int flags, ion_user_handle_t *handle)
-{
-    int ret;
+int ion_alloc(int fd, size_t len, size_t align, unsigned int heap_mask, unsigned int flags,
+              ion_user_handle_t* handle) {
+    int ret = 0;
+
+    if ((handle == NULL) || (!ion_is_legacy(fd))) return -EINVAL;
+
     struct ion_allocation_data data = {
-        .len = len,
-        .align = align,
-        .heap_id_mask = heap_mask,
-        .flags = flags,
+        .len = len, .align = align, .heap_id_mask = heap_mask, .flags = flags,
     };
 
-    if (handle == NULL)
-        return -EINVAL;
-
     ret = ion_ioctl(fd, ION_IOC_ALLOC, &data);
-    if (ret < 0)
-        return ret;
+    if (ret < 0) return ret;
+
     *handle = data.handle;
+
     return ret;
 }
 
-int ion_free(int fd, ion_user_handle_t handle)
-{
+int ion_free(int fd, ion_user_handle_t handle) {
     struct ion_handle_data data = {
         .handle = handle,
     };
     return ion_ioctl(fd, ION_IOC_FREE, &data);
 }
 
-int ion_map(int fd, ion_user_handle_t handle, size_t length, int prot,
-            int flags, off_t offset, unsigned char **ptr, int *map_fd)
-{
+int ion_map(int fd, ion_user_handle_t handle, size_t length, int prot, int flags, off_t offset,
+            unsigned char** ptr, int* map_fd) {
+    if (!ion_is_legacy(fd)) return -EINVAL;
     int ret;
-    unsigned char *tmp_ptr;
+    unsigned char* tmp_ptr;
     struct ion_fd_data data = {
         .handle = handle,
     };
 
-    if (map_fd == NULL)
-        return -EINVAL;
-    if (ptr == NULL)
-        return -EINVAL;
+    if (map_fd == NULL) return -EINVAL;
+    if (ptr == NULL) return -EINVAL;
 
     ret = ion_ioctl(fd, ION_IOC_MAP, &data);
-    if (ret < 0)
-        return ret;
+    if (ret < 0) return ret;
     if (data.fd < 0) {
         ALOGE("map ioctl returned negative fd\n");
         return -EINVAL;
@@ -119,19 +128,17 @@ int ion_map(int fd, ion_user_handle_t handle, size_t length, int prot,
     return ret;
 }
 
-int ion_share(int fd, ion_user_handle_t handle, int *share_fd)
-{
+int ion_share(int fd, ion_user_handle_t handle, int* share_fd) {
     int ret;
     struct ion_fd_data data = {
         .handle = handle,
     };
 
-    if (share_fd == NULL)
-        return -EINVAL;
+    if (!ion_is_legacy(fd)) return -EINVAL;
+    if (share_fd == NULL) return -EINVAL;
 
     ret = ion_ioctl(fd, ION_IOC_SHARE, &data);
-    if (ret < 0)
-        return ret;
+    if (ret < 0) return ret;
     if (data.fd < 0) {
         ALOGE("share ioctl returned negative fd\n");
         return -EINVAL;
@@ -140,40 +147,75 @@ int ion_share(int fd, ion_user_handle_t handle, int *share_fd)
     return ret;
 }
 
-int ion_alloc_fd(int fd, size_t len, size_t align, unsigned int heap_mask,
-                 unsigned int flags, int *handle_fd) {
+int ion_alloc_fd(int fd, size_t len, size_t align, unsigned int heap_mask, unsigned int flags,
+                 int* handle_fd) {
     ion_user_handle_t handle;
     int ret;
 
-    ret = ion_alloc(fd, len, align, heap_mask, flags, &handle);
-    if (ret < 0)
-        return ret;
-    ret = ion_share(fd, handle, handle_fd);
-    ion_free(fd, handle);
+    if (!ion_is_legacy(fd)) {
+        struct ion_new_allocation_data data = {
+            .len = len,
+            .heap_id_mask = heap_mask,
+            .flags = flags,
+        };
+
+        ret = ion_ioctl(fd, ION_IOC_NEW_ALLOC, &data);
+        if (ret < 0) return ret;
+        *handle_fd = data.fd;
+    } else {
+        ret = ion_alloc(fd, len, align, heap_mask, flags, &handle);
+        if (ret < 0) return ret;
+        ret = ion_share(fd, handle, handle_fd);
+        ion_free(fd, handle);
+    }
     return ret;
 }
 
-int ion_import(int fd, int share_fd, ion_user_handle_t *handle)
-{
+int ion_import(int fd, int share_fd, ion_user_handle_t* handle) {
     int ret;
     struct ion_fd_data data = {
         .fd = share_fd,
     };
 
-    if (handle == NULL)
-        return -EINVAL;
+    if (!ion_is_legacy(fd)) return -EINVAL;
+
+    if (handle == NULL) return -EINVAL;
 
     ret = ion_ioctl(fd, ION_IOC_IMPORT, &data);
-    if (ret < 0)
-        return ret;
+    if (ret < 0) return ret;
     *handle = data.handle;
     return ret;
 }
 
-int ion_sync_fd(int fd, int handle_fd)
-{
+int ion_sync_fd(int fd, int handle_fd) {
     struct ion_fd_data data = {
         .fd = handle_fd,
     };
+
+    if (!ion_is_legacy(fd)) return -EINVAL;
+
     return ion_ioctl(fd, ION_IOC_SYNC, &data);
 }
+
+int ion_query_heap_cnt(int fd, int* cnt) {
+    int ret;
+    struct ion_heap_query query;
+
+    memset(&query, 0, sizeof(query));
+
+    ret = ion_ioctl(fd, ION_IOC_HEAP_QUERY, &query);
+    if (ret < 0) return ret;
+
+    *cnt = query.cnt;
+    return ret;
+}
+
+int ion_query_get_heaps(int fd, int cnt, void* buffers) {
+    int ret;
+    struct ion_heap_query query = {
+        .cnt = cnt, .heaps = (uintptr_t)buffers,
+    };
+
+    ret = ion_ioctl(fd, ION_IOC_HEAP_QUERY, &query);
+    return ret;
+}