ulib Non-partitioned umalloc implementation

ulib/umalloc/umalloc.c

@@ -9,147 +9,7 @@
 #include <util/util.h>
 #include <assert.h>
 
-#define ARENA_SIZE (1<<20)
-#define BLOCK_MAGIC 0xDEADBEEF
-
-typedef struct UmArena {
-  struct UmArena *next;
-  uintptr_t mem;
-  uintptr_t base;
-  size_t cursor;
-  int64_t balance;
-} __attribute__((aligned(16))) UmArena;
-
-typedef struct {
-  uint32_t magic;
-  size_t size;
-  uint8_t data[];
-} __attribute__((aligned(16))) UmBlock;
-
-static UmArena *ARENAS = NULL;
-
-UmArena *um_newarena(void) {
-  size_t arenasize = ARENA_SIZE;
-
-  uint8_t *mem = NULL;
-  int32_t err = mman_map(NULL, arenasize, MMAN_MAP_PF_RW, 0, &mem);
-  if (mem == NULL || err != E_OK) {
-    return NULL;
-  }
-
-  UmArena *arena = (UmArena *)mem;
-  arena->base = (uintptr_t)mem;
-  arena->mem = ((uintptr_t)mem + sizeof(UmArena) + 15) & ~0xF;
-  arena->cursor = 0;
-  arena->balance = 0;
-  LL_APPEND(ARENAS, arena);
-
-  return arena;
-}
-
 void *umalloc(size_t size) {
-  UmArena *usable = NULL;
-
-  size = (size + 15) & ~(size_t)0xF;
-
-  UmArena *arena, *arenatmp;
-  LL_FOREACH_SAFE(ARENAS, arena, arenatmp) {
-    if (arena->cursor + sizeof(UmBlock) + size <= ARENA_SIZE - ((uintptr_t)arena->mem - arena->base)) {
-      usable = arena;
-      break;
-    }
-  }
-
-  if (usable == NULL) {
-    usable = um_newarena();
-  }
-
-  if (usable == NULL) {
-    return NULL;
-  }
-
-  uintptr_t addr = usable->mem + usable->cursor;
-  UmBlock *block = (UmBlock *)addr;
-  block->size = size;
-  block->magic = BLOCK_MAGIC;
-
-  usable->cursor += sizeof(UmBlock) + size;
-  usable->balance += size;
-
-  string_memset(block->data, 0, size);
-  return block->data;
-}
-
-void ufree(void *ptr_) {
-  if (ptr_ == NULL) {
-    return;
-  }
-
-  uintptr_t ptr = (uintptr_t)ptr_;
-
-  UmArena *freeable = NULL;
-  size_t size = 0;
-
-  UmArena *arena, *arenatmp;
-  LL_FOREACH_SAFE(ARENAS, arena, arenatmp) {
-    if (ptr >= arena->mem && ptr < arena->mem + arena->cursor) {
-      UmBlock *block = (UmBlock *)(ptr - sizeof(UmBlock));
-
-      if (((uintptr_t)block->data != ptr)
-       || (block->magic != BLOCK_MAGIC)
-       || (block->size == 0)
-       || (block->size > ARENA_SIZE)) {
-        return;
-      }
-
-      string_memset(block->data, 0xDD, block->size);
-      block->magic = 0;
-
-      arena->balance -= block->size;
-      ASSERT(arena->balance >= 0, "umalloc: imbalance after free\n");
-
-      if (arena->balance == 0) {
-        LL_REMOVE(ARENAS, arena);
-        mman_unmap((void *)arena->base);
-      }
-
-      return;
-    }
-  }
-}
-
-void *urealloc(void *ptr, size_t newsize) {
-  void *new;
-
-  UmBlock *block = (UmBlock *)(ptr - sizeof(UmBlock));
-  if (block->magic != BLOCK_MAGIC || block->data != ptr) {
-    goto err;
-  }
-
-  if (!ptr) {
-    new = umalloc(newsize);
-    if (!new) {
-      goto err;
-    }
-  } else {
-    if (block->size < newsize) {
-      new = umalloc(newsize);
-      if (!new) {
-        goto err;
-      }
-      string_memcpy(new, ptr, block->size);
-      ufree(ptr);
-    } else {
-      new = ptr;
-    }
-  }
-  return new;
-
-err:
-  return NULL;
-}
-
-void *umallocbig(size_t size) {
   size_t allocsz = ALIGN_UP(size, 4096);
   uint8_t *out;
   int32_t ret = mman_map(NULL, allocsz, MMAN_MAP_PF_RW, 0, &out);
@@ -159,7 +19,18 @@ void *umallocbig(size_t size) {
   return out;
 }
 
-void ufreebig(void *addr) {
+void ufree(void *addr) {
   if (addr != NULL)
     mman_unmap(addr);
 }
+
+void *urealloc(void *addr, size_t oldsize, size_t newsize) {
+  void *tmp = umalloc(newsize);
+  if (tmp == NULL) {
+    return NULL;
+  }
+  string_memset(tmp, 0, newsize);
+  string_memcpy(tmp, addr, oldsize);
+  ufree(addr);
+  return tmp;
+}