[sysmem] Introduce basic functionality to sysmem
With this CL, Sysmem can now be used to allocate
basic bufffer collections through the AllocateCollection
function.
BufferUsages are currently ignored, and multiplanar formats
are not supported. This Is really just to test out the basics
of Sysmem.
TEST = CQ
Change-Id: I851c71e41373a577eab59f7872c25856ae409cb9
diff --git a/system/ulib/sysmem/rules.mk b/system/ulib/sysmem/rules.mk
index 8a31bab..4b3383a 100644
--- a/system/ulib/sysmem/rules.mk
+++ b/system/ulib/sysmem/rules.mk
@@ -19,7 +19,10 @@
MODULE_STATIC_LIBS := \
system/ulib/async \
+ system/ulib/ddk \
system/ulib/fidl \
+ system/ulib/fbl \
+ system/ulib/zx \
MODULE_LIBS := \
system/ulib/fdio \
diff --git a/system/ulib/sysmem/sysmem.cpp b/system/ulib/sysmem/sysmem.cpp
index 1981226..f13d2ae 100644
--- a/system/ulib/sysmem/sysmem.cpp
+++ b/system/ulib/sysmem/sysmem.cpp
@@ -4,11 +4,22 @@
#include <lib/sysmem/sysmem.h>
+#include <fbl/algorithm.h>
#include <fuchsia/sysmem/c/fidl.h>
#include <lib/fidl/bind.h>
+#include <ddk/debug.h>
+#include <lib/zx/vmo.h>
#include <string.h>
+#include <zircon/assert.h>
#include <zircon/syscalls.h>
+// This should be called with a fully specified BufferFormat, after the allocator has
+// decided what format to use:
+size_t GetBufferSize(const fuchsia_sysmem_BufferFormat& format) {
+ // Simple GetBufferSize. Only valid for simple formats:
+ return fbl::round_up(format.image.height * format.image.planes[0].bytes_per_row, ZX_PAGE_SIZE);
+}
+
static zx_status_t Allocator_AllocateCollection(void* ctx,
uint32_t buffer_count,
const fuchsia_sysmem_BufferSpec* spec,
@@ -16,7 +27,32 @@
fidl_txn_t* txn) {
fuchsia_sysmem_BufferCollectionInfo info;
memset(&info, 0, sizeof(info));
- return fuchsia_sysmem_AllocatorAllocateCollection_reply(txn, ZX_ERR_NOT_SUPPORTED, &info);
+ // Most basic usage of the allocator: create vmos with no special vendor format:
+ // 1) Pick which format gets used. For the simple case, just use whatever format was given.
+ // We also assume here that the format is an ImageFormat
+ ZX_ASSERT(info.format.tag == fuchsia_sysmem_BufferFormatTagimage);
+ info.format = *format;
+
+ // 2) Determine the size of the buffer from the format.
+ info.vmo_size = GetBufferSize(info.format);
+
+ // 3) Allocate the buffers. This will be specialized for different formats.
+ info.buffer_count = buffer_count;
+ zx_status_t status;
+ for (uint32_t i = 0; i < buffer_count; ++i) {
+ status = zx_vmo_create(info.vmo_size, 0, &info.vmos[i]);
+ if (status != ZX_OK) {
+ // Close the handles we created already. We do not support partial allocations.
+ for (uint32_t j = 0; j < i; ++j) {
+ zx_handle_close(info.vmos[j]);
+ }
+ info.buffer_count = 0;
+ zxlogf(ERROR, "Failed to allocate Buffer Collection\n");
+ return fuchsia_sysmem_AllocatorAllocateCollection_reply(txn, ZX_ERR_NO_MEMORY, &info);
+ }
+ }
+ // If everything is happy and allocated, can give ZX_OK:
+ return fuchsia_sysmem_AllocatorAllocateCollection_reply(txn, ZX_OK, &info);
}
static zx_status_t Allocator_AllocateSharedCollection(void* ctx,
