layers_extensions.cpp revision 50db9035b034385a27fb557e4da3c48b51a0e3eb 
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    PFN_vkEnumerateDeviceLayerProperties enumerate_device_layers =
135        reinterpret_cast<PFN_vkEnumerateDeviceLayerProperties>(
136            dlsym(dlhandle_, "vkEnumerateDeviceLayerProperties"));
137    PFN_vkEnumerateDeviceExtensionProperties enumerate_device_extensions =
138        reinterpret_cast<PFN_vkEnumerateDeviceExtensionProperties>(
139            dlsym(dlhandle_, "vkEnumerateDeviceExtensionProperties"));
140    if (!((enumerate_instance_layers && enumerate_instance_extensions) ||
141          (enumerate_device_layers && enumerate_device_extensions))) {
142        ALOGV(
143            "layer library '%s' has neither instance nor device enumeraion "
144            "functions",
145            path_.c_str());
146        return false;
147    }
148
149    VkResult result;
150    uint32_t num_instance_layers = 0;
151    uint32_t num_device_layers = 0;
152    if (enumerate_instance_layers) {
153        result = enumerate_instance_layers(&num_instance_layers, nullptr);
154        if (result != VK_SUCCESS) {
155            ALOGW(
156                "vkEnumerateInstanceLayerProperties failed for library '%s': "
157                "%d",
158                path_.c_str(), result);
159            return false;
160        }
161    }
162    if (enumerate_device_layers) {
163        result = enumerate_device_layers(VK_NULL_HANDLE, &num_device_layers,
164                                         nullptr);
165        if (result != VK_SUCCESS) {
166            ALOGW(
167                "vkEnumerateDeviceLayerProperties failed for library '%s': %d",
168                path_.c_str(), result);
169            return false;
170        }
171    }
172    VkLayerProperties* properties = static_cast<VkLayerProperties*>(alloca(
173        (num_instance_layers + num_device_layers) * sizeof(VkLayerProperties)));
174    if (num_instance_layers > 0) {
175        result = enumerate_instance_layers(&num_instance_layers, properties);
176        if (result != VK_SUCCESS) {
177            ALOGW(
178                "vkEnumerateInstanceLayerProperties failed for library '%s': "
179                "%d",
180                path_.c_str(), result);
181            return false;
182        }
183    }
184    if (num_device_layers > 0) {
185        result = enumerate_device_layers(VK_NULL_HANDLE, &num_device_layers,
186                                         properties + num_instance_layers);
187        if (result != VK_SUCCESS) {
188            ALOGW(
189                "vkEnumerateDeviceLayerProperties failed for library '%s': %d",
190                path_.c_str(), result);
191            return false;
192        }
193    }
194
195    size_t prev_num_instance_layers = instance_layers.size();
196    size_t prev_num_device_layers = device_layers.size();
197    instance_layers.reserve(prev_num_instance_layers + num_instance_layers);
198    device_layers.reserve(prev_num_device_layers + num_device_layers);
199    for (size_t i = 0; i < num_instance_layers; i++) {
200        const VkLayerProperties& props = properties[i];
201
202        Layer layer;
203        layer.properties = props;
204        layer.library_idx = library_idx;
205
206        if (enumerate_instance_extensions) {
207            uint32_t count = 0;
208            result =
209                enumerate_instance_extensions(props.layerName, &count, nullptr);
210            if (result != VK_SUCCESS) {
211                ALOGW(
212                    "vkEnumerateInstanceExtensionProperties(%s) failed for "
213                    "library '%s': %d",
214                    props.layerName, path_.c_str(), result);
215                instance_layers.resize(prev_num_instance_layers);
216                return false;
217            }
218            layer.extensions.resize(count);
219            result = enumerate_instance_extensions(props.layerName, &count,
220                                                   layer.extensions.data());
221            if (result != VK_SUCCESS) {
222                ALOGW(
223                    "vkEnumerateInstanceExtensionProperties(%s) failed for "
224                    "library '%s': %d",
225                    props.layerName, path_.c_str(), result);
226                instance_layers.resize(prev_num_instance_layers);
227                return false;
228            }
229        }
230
231        instance_layers.push_back(layer);
232        ALOGV("  added instance layer '%s'", props.layerName);
233    }
234    for (size_t i = 0; i < num_device_layers; i++) {
235        const VkLayerProperties& props = properties[num_instance_layers + i];
236
237        Layer layer;
238        layer.properties = props;
239        layer.library_idx = library_idx;
240
241        if (enumerate_device_extensions) {
242            uint32_t count;
243            result = enumerate_device_extensions(
244                VK_NULL_HANDLE, props.layerName, &count, nullptr);
245            if (result != VK_SUCCESS) {
246                ALOGW(
247                    "vkEnumerateDeviceExtensionProperties(%s) failed for "
248                    "library '%s': %d",
249                    props.layerName, path_.c_str(), result);
250                instance_layers.resize(prev_num_instance_layers);
251                device_layers.resize(prev_num_device_layers);
252                return false;
253            }
254            layer.extensions.resize(count);
255            result =
256                enumerate_device_extensions(VK_NULL_HANDLE, props.layerName,
257                                            &count, layer.extensions.data());
258            if (result != VK_SUCCESS) {
259                ALOGW(
260                    "vkEnumerateDeviceExtensionProperties(%s) failed for "
261                    "library '%s': %d",
262                    props.layerName, path_.c_str(), result);
263                instance_layers.resize(prev_num_instance_layers);
264                device_layers.resize(prev_num_device_layers);
265                return false;
266            }
267        }
268
269        device_layers.push_back(layer);
270        ALOGV("  added device layer '%s'", props.layerName);
271    }
272
273    return true;
274}
275
276void* LayerLibrary::GetGPA(const Layer& layer,
277                           const char* gpa_name,
278                           size_t gpa_name_len) const {
279    void* gpa;
280    size_t layer_name_len =
281        std::max(size_t{2}, strlen(layer.properties.layerName));
282    char* name = static_cast<char*>(alloca(layer_name_len + gpa_name_len + 1));
283    strcpy(name, layer.properties.layerName);
284    strcpy(name + layer_name_len, gpa_name);
285    if (!(gpa = dlsym(dlhandle_, name))) {
286        strcpy(name, "vk");
287        strcpy(name + 2, gpa_name);
288        gpa = dlsym(dlhandle_, name);
289    }
290    return gpa;
291}
292
293std::vector<LayerLibrary> g_layer_libraries;
294std::vector<Layer> g_instance_layers;
295std::vector<Layer> g_device_layers;
296
297void AddLayerLibrary(const std::string& path) {
298    ALOGV("examining layer library '%s'", path.c_str());
299
300    LayerLibrary library(path);
301    if (!library.Open())
302        return;
303
304    if (!library.EnumerateLayers(g_layer_libraries.size(), g_instance_layers,
305                                 g_device_layers)) {
306        library.Close();
307        return;
308    }
309
310    library.Close();
311
312    g_layer_libraries.emplace_back(std::move(library));
313}
314
315void DiscoverLayersInDirectory(const std::string& dir_path) {
316    ALOGV("looking for layers in '%s'", dir_path.c_str());
317
318    DIR* directory = opendir(dir_path.c_str());
319    if (!directory) {
320        int err = errno;
321        ALOGV_IF(err != ENOENT, "failed to open layer directory '%s': %s (%d)",
322                 dir_path.c_str(), strerror(err), err);
323        return;
324    }
325
326    std::string path;
327    path.reserve(dir_path.size() + 20);
328    path.append(dir_path);
329    path.append("/");
330
331    struct dirent* entry;
332    while ((entry = readdir(directory))) {
333        size_t libname_len = strlen(entry->d_name);
334        if (strncmp(entry->d_name, "libVkLayer", 10) != 0 ||
335            strncmp(entry->d_name + libname_len - 3, ".so", 3) != 0)
336            continue;
337        path.append(entry->d_name);
338        AddLayerLibrary(path);
339        path.resize(dir_path.size() + 1);
340    }
341
342    closedir(directory);
343}
344
345const Layer* FindLayer(const std::vector<Layer>& layers, const char* name) {
346    auto layer =
347        std::find_if(layers.cbegin(), layers.cend(), [=](const Layer& entry) {
348            return strcmp(entry.properties.layerName, name) == 0;
349        });
350    return (layer != layers.cend()) ? &*layer : nullptr;
351}
352
353void* GetLayerGetProcAddr(const Layer& layer,
354                          const char* gpa_name,
355                          size_t gpa_name_len) {
356    const LayerLibrary& library = g_layer_libraries[layer.library_idx];
357    return library.GetGPA(layer, gpa_name, gpa_name_len);
358}
359
360uint32_t EnumerateLayers(const std::vector<Layer>& layers,
361                         uint32_t count,
362                         VkLayerProperties* properties) {
363    uint32_t n = std::min(count, static_cast<uint32_t>(layers.size()));
364    for (uint32_t i = 0; i < n; i++) {
365        properties[i] = layers[i].properties;
366    }
367    return static_cast<uint32_t>(layers.size());
368}
369
370void GetLayerExtensions(const std::vector<Layer>& layers,
371                        const char* name,
372                        const VkExtensionProperties** properties,
373                        uint32_t* count) {
374    const Layer* layer = FindLayer(layers, name);
375    if (layer) {
376        *properties = layer->extensions.data();
377        *count = static_cast<uint32_t>(layer->extensions.size());
378    } else {
379        *properties = nullptr;
380        *count = 0;
381    }
382}
383
384LayerRef GetLayerRef(std::vector<Layer>& layers, const char* name) {
385    const Layer* layer = FindLayer(layers, name);
386    if (layer) {
387        LayerLibrary& library = g_layer_libraries[layer->library_idx];
388        if (!library.Open())
389            layer = nullptr;
390    }
391
392    return LayerRef(layer);
393}
394
395}  // anonymous namespace
396
397void DiscoverLayers() {
398    if (prctl(PR_GET_DUMPABLE, 0, 0, 0, 0))
399        DiscoverLayersInDirectory("/data/local/debug/vulkan");
400    if (!LoaderData::GetInstance().layer_path.empty())
401        DiscoverLayersInDirectory(LoaderData::GetInstance().layer_path.c_str());
402}
403
404uint32_t EnumerateInstanceLayers(uint32_t count,
405                                 VkLayerProperties* properties) {
406    return EnumerateLayers(g_instance_layers, count, properties);
407}
408
409uint32_t EnumerateDeviceLayers(uint32_t count, VkLayerProperties* properties) {
410    return EnumerateLayers(g_device_layers, count, properties);
411}
412
413void GetInstanceLayerExtensions(const char* name,
414                                const VkExtensionProperties** properties,
415                                uint32_t* count) {
416    GetLayerExtensions(g_instance_layers, name, properties, count);
417}
418
419void GetDeviceLayerExtensions(const char* name,
420                              const VkExtensionProperties** properties,
421                              uint32_t* count) {
422    GetLayerExtensions(g_device_layers, name, properties, count);
423}
424
425LayerRef GetInstanceLayerRef(const char* name) {
426    return GetLayerRef(g_instance_layers, name);
427}
428
429LayerRef GetDeviceLayerRef(const char* name) {
430    return GetLayerRef(g_device_layers, name);
431}
432
433LayerRef::LayerRef(const Layer* layer) : layer_(layer) {}
434
435LayerRef::~LayerRef() {
436    if (layer_) {
437        LayerLibrary& library = g_layer_libraries[layer_->library_idx];
438        library.Close();
439    }
440}
441
442const char* LayerRef::GetName() const {
443    return layer_->properties.layerName;
444}
445
446uint32_t LayerRef::GetSpecVersion() const {
447    return layer_->properties.specVersion;
448}
449
450LayerRef::LayerRef(LayerRef&& other) : layer_(std::move(other.layer_)) {
451    other.layer_ = nullptr;
452}
453
454PFN_vkGetInstanceProcAddr LayerRef::GetGetInstanceProcAddr() const {
455    return layer_ ? reinterpret_cast<PFN_vkGetInstanceProcAddr>(
456                        GetLayerGetProcAddr(*layer_, "GetInstanceProcAddr", 19))
457                  : nullptr;
458}
459
460PFN_vkGetDeviceProcAddr LayerRef::GetGetDeviceProcAddr() const {
461    return layer_ ? reinterpret_cast<PFN_vkGetDeviceProcAddr>(
462                        GetLayerGetProcAddr(*layer_, "GetDeviceProcAddr", 17))
463                  : nullptr;
464}
465
466bool LayerRef::SupportsExtension(const char* name) const {
467    return std::find_if(layer_->extensions.cbegin(), layer_->extensions.cend(),
468                        [=](const VkExtensionProperties& ext) {
469                            return strcmp(ext.extensionName, name) == 0;
470                        }) != layer_->extensions.cend();
471}
472
473}  // namespace api
474}  // namespace vulkan
475