layers_extensions.cpp revision 5f093bf18120a5cbf18d0f3e255b2178f524e438 
1/*
2 * Copyright 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17// #define LOG_NDEBUG 0
18
19#include "layers_extensions.h"
20#include <alloca.h>
21#include <dirent.h>
22#include <dlfcn.h>
23#include <mutex>
24#include <sys/prctl.h>
25#include <string>
26#include <string.h>
27#include <vector>
28#include <log/log.h>
29#include <vulkan/vulkan_loader_data.h>
30
31// TODO(jessehall): The whole way we deal with extensions is pretty hokey, and
32// not a good long-term solution. Having a hard-coded enum of extensions is
33// bad, of course. Representing sets of extensions (requested, supported, etc.)
34// as a bitset isn't necessarily bad, if the mapping from extension to bit were
35// dynamic. Need to rethink this completely when there's a little more time.
36
37// TODO(jessehall): This file currently builds up global data structures as it
38// loads, and never cleans them up. This means we're doing heap allocations
39// without going through an app-provided allocator, but worse, we'll leak those
40// allocations if the loader is unloaded.
41//
42// We should allocate "enough" BSS space, and suballocate from there. Will
43// probably want to intern strings, etc., and will need some custom/manual data
44// structures.
45
46// TODO(jessehall): Currently we have separate lists for instance and device
47// layers. Most layers are both; we should use one entry for each layer name,
48// with a mask saying what kind(s) it is.
49
50namespace vulkan {
51namespace api {
52
53struct Layer {
54    VkLayerProperties properties;
55    size_t library_idx;
56    std::vector<VkExtensionProperties> extensions;
57};
58
59namespace {
60
61class LayerLibrary {
62   public:
63    LayerLibrary(const std::string& path)
64        : path_(path), dlhandle_(nullptr), refcount_(0) {}
65
66    LayerLibrary(LayerLibrary&& other)
67        : path_(std::move(other.path_)),
68          dlhandle_(other.dlhandle_),
69          refcount_(other.refcount_) {
70        other.dlhandle_ = nullptr;
71        other.refcount_ = 0;
72    }
73
74    LayerLibrary(const LayerLibrary&) = delete;
75    LayerLibrary& operator=(const LayerLibrary&) = delete;
76
77    // these are thread-safe
78    bool Open();
79    void Close();
80
81    bool EnumerateLayers(size_t library_idx,
82                         std::vector<Layer>& instance_layers,
83                         std::vector<Layer>& device_layers) const;
84
85    void* GetGPA(const Layer& layer,
86                 const char* gpa_name,
87                 size_t gpa_name_len) const;
88
89   private:
90    const std::string path_;
91
92    std::mutex mutex_;
93    void* dlhandle_;
94    size_t refcount_;
95};
96
97bool LayerLibrary::Open() {
98    std::lock_guard<std::mutex> lock(mutex_);
99
100    if (refcount_++ == 0) {
101        dlhandle_ = dlopen(path_.c_str(), RTLD_NOW | RTLD_LOCAL);
102        ALOGV("Opening library %s", path_.c_str());
103        if (!dlhandle_) {
104            ALOGE("failed to load layer library '%s': %s", path_.c_str(),
105                  dlerror());
106            refcount_ = 0;
107            return false;
108        }
109    }
110    ALOGV("Refcount on activate is %zu", refcount_);
111    return true;
112}
113
114void LayerLibrary::Close() {
115    std::lock_guard<std::mutex> lock(mutex_);
116
117    if (--refcount_ == 0) {
118        ALOGV("Closing library %s", path_.c_str());
119        dlclose(dlhandle_);
120        dlhandle_ = nullptr;
121    }
122    ALOGV("Refcount on destruction is %zu", refcount_);
123}
124
125bool LayerLibrary::EnumerateLayers(size_t library_idx,
126                                   std::vector<Layer>& instance_layers,
127                                   std::vector<Layer>& device_layers) const {
128    PFN_vkEnumerateInstanceLayerProperties enumerate_instance_layers =
129        reinterpret_cast<PFN_vkEnumerateInstanceLayerProperties>(
130            dlsym(dlhandle_, "vkEnumerateInstanceLayerProperties"));
131    PFN_vkEnumerateInstanceExtensionProperties enumerate_instance_extensions =
132        reinterpret_cast<PFN_vkEnumerateInstanceExtensionProperties>(
133            dlsym(dlhandle_, "vkEnumerateInstanceExtensionProperties"));
134    if (!enumerate_instance_layers || !enumerate_instance_extensions) {
135        ALOGV("layer library '%s' misses some instance enumeraion functions",
136              path_.c_str());
137        return false;
138    }
139
140    // device functions are optional
141    PFN_vkEnumerateDeviceLayerProperties enumerate_device_layers =
142        reinterpret_cast<PFN_vkEnumerateDeviceLayerProperties>(
143            dlsym(dlhandle_, "vkEnumerateDeviceLayerProperties"));
144    PFN_vkEnumerateDeviceExtensionProperties enumerate_device_extensions =
145        reinterpret_cast<PFN_vkEnumerateDeviceExtensionProperties>(
146            dlsym(dlhandle_, "vkEnumerateDeviceExtensionProperties"));
147
148    // get layer counts
149    uint32_t num_instance_layers = 0;
150    uint32_t num_device_layers = 0;
151    VkResult result = enumerate_instance_layers(&num_instance_layers, nullptr);
152    if (result != VK_SUCCESS || !num_instance_layers) {
153        if (result != VK_SUCCESS) {
154            ALOGW(
155                "vkEnumerateInstanceLayerProperties failed for library '%s': "
156                "%d",
157                path_.c_str(), result);
158        }
159        return false;
160    }
161    if (enumerate_device_layers) {
162        result = enumerate_device_layers(VK_NULL_HANDLE, &num_device_layers,
163                                         nullptr);
164        if (result != VK_SUCCESS) {
165            ALOGW(
166                "vkEnumerateDeviceLayerProperties failed for library '%s': %d",
167                path_.c_str(), result);
168            return false;
169        }
170    }
171
172    // get layer properties
173    VkLayerProperties* properties = static_cast<VkLayerProperties*>(alloca(
174        (num_instance_layers + num_device_layers) * sizeof(VkLayerProperties)));
175    result = enumerate_instance_layers(&num_instance_layers, properties);
176    if (result != VK_SUCCESS) {
177        ALOGW("vkEnumerateInstanceLayerProperties failed for library '%s': %d",
178              path_.c_str(), result);
179        return false;
180    }
181    if (num_device_layers > 0) {
182        result = enumerate_device_layers(VK_NULL_HANDLE, &num_device_layers,
183                                         properties + num_instance_layers);
184        if (result != VK_SUCCESS) {
185            ALOGW(
186                "vkEnumerateDeviceLayerProperties failed for library '%s': %d",
187                path_.c_str(), result);
188            return false;
189        }
190    }
191
192    // append layers to instance_layers/device_layers
193    size_t prev_num_instance_layers = instance_layers.size();
194    size_t prev_num_device_layers = device_layers.size();
195    instance_layers.reserve(prev_num_instance_layers + num_instance_layers);
196    device_layers.reserve(prev_num_device_layers + num_device_layers);
197    for (size_t i = 0; i < num_instance_layers; i++) {
198        const VkLayerProperties& props = properties[i];
199
200        Layer layer;
201        layer.properties = props;
202        layer.library_idx = library_idx;
203
204        uint32_t count = 0;
205        result =
206            enumerate_instance_extensions(props.layerName, &count, nullptr);
207        if (result != VK_SUCCESS) {
208            ALOGW(
209                "vkEnumerateInstanceExtensionProperties(%s) failed for library "
210                "'%s': %d",
211                props.layerName, path_.c_str(), result);
212            instance_layers.resize(prev_num_instance_layers);
213            return false;
214        }
215        layer.extensions.resize(count);
216        result = enumerate_instance_extensions(props.layerName, &count,
217                                               layer.extensions.data());
218        if (result != VK_SUCCESS) {
219            ALOGW(
220                "vkEnumerateInstanceExtensionProperties(%s) failed for library "
221                "'%s': %d",
222                props.layerName, path_.c_str(), result);
223            instance_layers.resize(prev_num_instance_layers);
224            return false;
225        }
226
227        instance_layers.push_back(layer);
228        ALOGV("  added instance layer '%s'", props.layerName);
229    }
230    for (size_t i = 0; i < num_device_layers; i++) {
231        const VkLayerProperties& props = properties[num_instance_layers + i];
232
233        Layer layer;
234        layer.properties = props;
235        layer.library_idx = library_idx;
236
237        if (enumerate_device_extensions) {
238            uint32_t count;
239            result = enumerate_device_extensions(
240                VK_NULL_HANDLE, props.layerName, &count, nullptr);
241            if (result != VK_SUCCESS) {
242                ALOGW(
243                    "vkEnumerateDeviceExtensionProperties(%s) failed for "
244                    "library '%s': %d",
245                    props.layerName, path_.c_str(), result);
246                instance_layers.resize(prev_num_instance_layers);
247                device_layers.resize(prev_num_device_layers);
248                return false;
249            }
250            layer.extensions.resize(count);
251            result =
252                enumerate_device_extensions(VK_NULL_HANDLE, props.layerName,
253                                            &count, layer.extensions.data());
254            if (result != VK_SUCCESS) {
255                ALOGW(
256                    "vkEnumerateDeviceExtensionProperties(%s) failed for "
257                    "library '%s': %d",
258                    props.layerName, path_.c_str(), result);
259                instance_layers.resize(prev_num_instance_layers);
260                device_layers.resize(prev_num_device_layers);
261                return false;
262            }
263        }
264
265        device_layers.push_back(layer);
266        ALOGV("  added device layer '%s'", props.layerName);
267    }
268
269    return true;
270}
271
272void* LayerLibrary::GetGPA(const Layer& layer,
273                           const char* gpa_name,
274                           size_t gpa_name_len) const {
275    void* gpa;
276    size_t layer_name_len =
277        std::max(size_t{2}, strlen(layer.properties.layerName));
278    char* name = static_cast<char*>(alloca(layer_name_len + gpa_name_len + 1));
279    strcpy(name, layer.properties.layerName);
280    strcpy(name + layer_name_len, gpa_name);
281    if (!(gpa = dlsym(dlhandle_, name))) {
282        strcpy(name, "vk");
283        strcpy(name + 2, gpa_name);
284        gpa = dlsym(dlhandle_, name);
285    }
286    return gpa;
287}
288
289std::vector<LayerLibrary> g_layer_libraries;
290std::vector<Layer> g_instance_layers;
291std::vector<Layer> g_device_layers;
292
293void AddLayerLibrary(const std::string& path) {
294    ALOGV("examining layer library '%s'", path.c_str());
295
296    LayerLibrary library(path);
297    if (!library.Open())
298        return;
299
300    if (!library.EnumerateLayers(g_layer_libraries.size(), g_instance_layers,
301                                 g_device_layers)) {
302        library.Close();
303        return;
304    }
305
306    library.Close();
307
308    g_layer_libraries.emplace_back(std::move(library));
309}
310
311void DiscoverLayersInDirectory(const std::string& dir_path) {
312    ALOGV("looking for layers in '%s'", dir_path.c_str());
313
314    DIR* directory = opendir(dir_path.c_str());
315    if (!directory) {
316        int err = errno;
317        ALOGV_IF(err != ENOENT, "failed to open layer directory '%s': %s (%d)",
318                 dir_path.c_str(), strerror(err), err);
319        return;
320    }
321
322    std::string path;
323    path.reserve(dir_path.size() + 20);
324    path.append(dir_path);
325    path.append("/");
326
327    struct dirent* entry;
328    while ((entry = readdir(directory))) {
329        size_t libname_len = strlen(entry->d_name);
330        if (strncmp(entry->d_name, "libVkLayer", 10) != 0 ||
331            strncmp(entry->d_name + libname_len - 3, ".so", 3) != 0)
332            continue;
333        path.append(entry->d_name);
334        AddLayerLibrary(path);
335        path.resize(dir_path.size() + 1);
336    }
337
338    closedir(directory);
339}
340
341const Layer* FindLayer(const std::vector<Layer>& layers, const char* name) {
342    auto layer =
343        std::find_if(layers.cbegin(), layers.cend(), [=](const Layer& entry) {
344            return strcmp(entry.properties.layerName, name) == 0;
345        });
346    return (layer != layers.cend()) ? &*layer : nullptr;
347}
348
349void* GetLayerGetProcAddr(const Layer& layer,
350                          const char* gpa_name,
351                          size_t gpa_name_len) {
352    const LayerLibrary& library = g_layer_libraries[layer.library_idx];
353    return library.GetGPA(layer, gpa_name, gpa_name_len);
354}
355
356uint32_t EnumerateLayers(const std::vector<Layer>& layers,
357                         uint32_t count,
358                         VkLayerProperties* properties) {
359    uint32_t n = std::min(count, static_cast<uint32_t>(layers.size()));
360    for (uint32_t i = 0; i < n; i++) {
361        properties[i] = layers[i].properties;
362    }
363    return static_cast<uint32_t>(layers.size());
364}
365
366void GetLayerExtensions(const std::vector<Layer>& layers,
367                        const char* name,
368                        const VkExtensionProperties** properties,
369                        uint32_t* count) {
370    const Layer* layer = FindLayer(layers, name);
371    if (layer) {
372        *properties = layer->extensions.data();
373        *count = static_cast<uint32_t>(layer->extensions.size());
374    } else {
375        *properties = nullptr;
376        *count = 0;
377    }
378}
379
380LayerRef GetLayerRef(std::vector<Layer>& layers, const char* name) {
381    const Layer* layer = FindLayer(layers, name);
382    if (layer) {
383        LayerLibrary& library = g_layer_libraries[layer->library_idx];
384        if (!library.Open())
385            layer = nullptr;
386    }
387
388    return LayerRef(layer);
389}
390
391}  // anonymous namespace
392
393void DiscoverLayers() {
394    if (prctl(PR_GET_DUMPABLE, 0, 0, 0, 0))
395        DiscoverLayersInDirectory("/data/local/debug/vulkan");
396    if (!LoaderData::GetInstance().layer_path.empty())
397        DiscoverLayersInDirectory(LoaderData::GetInstance().layer_path.c_str());
398}
399
400uint32_t EnumerateInstanceLayers(uint32_t count,
401                                 VkLayerProperties* properties) {
402    return EnumerateLayers(g_instance_layers, count, properties);
403}
404
405uint32_t EnumerateDeviceLayers(uint32_t count, VkLayerProperties* properties) {
406    return EnumerateLayers(g_device_layers, count, properties);
407}
408
409void GetInstanceLayerExtensions(const char* name,
410                                const VkExtensionProperties** properties,
411                                uint32_t* count) {
412    GetLayerExtensions(g_instance_layers, name, properties, count);
413}
414
415void GetDeviceLayerExtensions(const char* name,
416                              const VkExtensionProperties** properties,
417                              uint32_t* count) {
418    GetLayerExtensions(g_device_layers, name, properties, count);
419}
420
421LayerRef GetInstanceLayerRef(const char* name) {
422    return GetLayerRef(g_instance_layers, name);
423}
424
425LayerRef GetDeviceLayerRef(const char* name) {
426    return GetLayerRef(g_device_layers, name);
427}
428
429LayerRef::LayerRef(const Layer* layer) : layer_(layer) {}
430
431LayerRef::~LayerRef() {
432    if (layer_) {
433        LayerLibrary& library = g_layer_libraries[layer_->library_idx];
434        library.Close();
435    }
436}
437
438const char* LayerRef::GetName() const {
439    return layer_->properties.layerName;
440}
441
442uint32_t LayerRef::GetSpecVersion() const {
443    return layer_->properties.specVersion;
444}
445
446LayerRef::LayerRef(LayerRef&& other) : layer_(std::move(other.layer_)) {
447    other.layer_ = nullptr;
448}
449
450PFN_vkGetInstanceProcAddr LayerRef::GetGetInstanceProcAddr() const {
451    return layer_ ? reinterpret_cast<PFN_vkGetInstanceProcAddr>(
452                        GetLayerGetProcAddr(*layer_, "GetInstanceProcAddr", 19))
453                  : nullptr;
454}
455
456PFN_vkGetDeviceProcAddr LayerRef::GetGetDeviceProcAddr() const {
457    return layer_ ? reinterpret_cast<PFN_vkGetDeviceProcAddr>(
458                        GetLayerGetProcAddr(*layer_, "GetDeviceProcAddr", 17))
459                  : nullptr;
460}
461
462bool LayerRef::SupportsExtension(const char* name) const {
463    return std::find_if(layer_->extensions.cbegin(), layer_->extensions.cend(),
464                        [=](const VkExtensionProperties& ext) {
465                            return strcmp(ext.extensionName, name) == 0;
466                        }) != layer_->extensions.cend();
467}
468
469}  // namespace api
470}  // namespace vulkan
471