meta: move photon/libc to root

libc/sys/horizon/heap.c

@@ -0,0 +1,101 @@
+#include <stdint.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <magenta/vmo.h>
+#include <magenta/bootstrap.h>
+#include <magenta/errors.h>
+#include <magenta/misc.h>
+#include <magenta/vmar.h>
+
+/* 1 GiB */
+#define HEAP_REGION_SZ 0x40000000
+
+#define ROUND_UP(x, b) x += (b) - ((x) % (b))
+
+static uintptr_t heap_start = 0;
+static uintptr_t heap_end = 0;
+static uintptr_t heap_alloc_point = 0;
+static size_t heap_sz = 0;
+static mx_handle_t heap_vmo = MX_NULL_HANDLE;
+static mx_handle_t heap_vmar = MX_NULL_HANDLE;
+
+void __crt_heap_init(size_t sz)
+{
+    mx_handle_t root_vmar = mx_bootstrap_handle_get(MX_B_VMAR_ROOT);
+    mx_vaddr_t heap = 0;
+
+    mx_status_t status = mx_vmar_allocate(root_vmar,
+            MX_VM_CAN_MAP_READ | MX_VM_CAN_MAP_WRITE | MX_VM_CAN_MAP_SPECIFIC,
+            0, HEAP_REGION_SZ, &heap_vmar, &heap);
+    if (status != MX_OK) {
+        fprintf(stderr, "fatal: cannot allocate heap virtual region (%s)\n", mx_status_to_string(status));
+        abort();
+    }
+
+    status = mx_vmo_create(
+            sz,
+            MX_VM_CAN_MAP_READ | MX_VM_CAN_MAP_WRITE | MX_VM_CAN_MAP_SPECIFIC,
+            &heap_vmo);
+    if (status != MX_OK) {
+        fprintf(stderr, "fatal: cannot allocate heap (%s)\n", mx_status_to_string(status));
+        abort();
+    }
+
+    status = mx_vmar_map(heap_vmar,
+            MX_VM_PERM_READ | MX_VM_PERM_WRITE | MX_VM_SPECIFIC,
+            0, heap_vmo, 0, sz,
+            &heap);
+    if (status != MX_OK) {
+        fprintf(stderr, "fatal: cannot map heap (%s)\n", mx_status_to_string(status));
+        abort();
+    }
+
+    heap_sz = sz;
+    heap_start = heap;
+    heap_end = heap + heap_sz;
+    heap_alloc_point = heap_start;
+
+    memset((void *)heap, 0x0, heap_sz);
+}
+
+void *__crt_heap_extend(size_t sz)
+{
+    if (sz % MX_PAGE_SIZE) {
+        sz &= (MX_PAGE_SIZE - 1);
+        sz += MX_PAGE_SIZE;
+    }
+
+    if (!sz) {
+        return (void *)heap_end;
+    }
+
+    if (!heap_start) {
+        __crt_heap_init(sz);
+        return (void *)heap_start;
+    }
+
+    mx_vmo_set_size(heap_vmo, heap_sz + sz);
+
+    mx_vaddr_t vmar_base, alloc_base;
+    mx_vmar_bounds(heap_vmar, &vmar_base, NULL);
+    size_t offset = heap_end - vmar_base;
+
+    mx_status_t err = mx_vmar_map(heap_vmar,
+            MX_VM_PERM_READ | MX_VM_PERM_WRITE | MX_VM_SPECIFIC,
+            offset, heap_vmo, heap_sz, sz, &alloc_base);
+
+    if (err != MX_OK) {
+        fprintf(stderr, "fatal: cannot map extended heap (%s)\n", mx_status_to_string(err));
+        abort();
+    }
+
+    heap_sz += sz;
+
+    void *out = (void *)heap_end;
+    memset(out, 0x0, sz);
+    heap_end += sz;
+
+    return out;
+}