3 files changed, 23 insertions, 11 deletions

diff --git a/lib/vita/execmem.c b/lib/vita/execmem.c
index 526b29b..84927d6 100644
--- a/lib/vita/execmem.c
+++ b/lib/vita/execmem.c
@@ -8,12 +8,15 @@
 /** The size of each trampoline allocation. We use it for outro and optional
  * intro. Realistically, we do not use an intro.
  */
-#define SLAB_SIZE (TD_MAX_REWRITTEN_SIZE + 2 * MAX_JUMP_PATCH_SIZE)
-#if (SLAB_SIZE % ARCH_MAX_CODE_ALIGNMENT != 0)
+#define SLAB_ITEM_SIZE (TD_MAX_REWRITTEN_SIZE + 2 * MAX_JUMP_PATCH_SIZE)
+#if (SLAB_ITEM_SIZE % ARCH_MAX_CODE_ALIGNMENT != 0)
 // if not aligned then substitute_hook_functions breaks!
-#error SLAB_SIZE Must be aligned to ARCH_MAX_CODE_ALIGNMENT
+#error SLAB_ITEM_SIZE Must be aligned to ARCH_MAX_CODE_ALIGNMENT
 #endif
 
+/** Allow other files to use this constant. */
+const int g_exe_slab_item_size = SLAB_ITEM_SIZE;
+
 /**
  * @file execmem.c
  *
@@ -34,7 +37,7 @@
  * @param[in]  hint       Unused
  * @param      ptr_p      The writable pointer
  * @param      vma_p      The executable pointer address
- * @param      size_p     The size of the allocation. Always `SLAB_SIZE`.
+ * @param      size_p     The size of the allocation. Always `SLAB_ITEM_SIZE`.
  * @param      opt        A `tai_substitute_args_t` structure
  * @param[in]  hint  Unused
  *
@@ -49,12 +52,11 @@ int execmem_alloc_unsealed(UNUSED uintptr_t hint, void **ptr_p, uintptr_t *vma_p
  * @brief      Flushes icache
  *
  * @param      ptr   Unused
- * @param[in]  vma   Pointer to flush
  * @param      opt   A `tai_substitute_args_t` structure
  *
  * @return     `SUBSTITUTE_OK`
  */
-int execmem_seal(UNUSED void *ptr, uintptr_t vma, void *opt) {
+int execmem_seal(UNUSED void *ptr, void *opt) {
     return SUBSTITUTE_OK;
 }
 
@@ -62,10 +64,9 @@ int execmem_seal(UNUSED void *ptr, uintptr_t vma, void *opt) {
  * @brief      Frees executable memory from slab allocator
  *
  * @param      ptr   The writable pointer
- * @param[in]  vma   The executable address. Must match with ptr.
  * @param      opt   A `tai_substitute_args_t` structure
  */
-void execmem_free(void *ptr, uintptr_t vma, void *opt) {
+void execmem_free(void *ptr, void *opt) {
 }
 
 /**
diff --git a/lib/vita/slab.c b/lib/vita/slab.c
index 0ca3529..91742a6 100755
--- a/lib/vita/slab.c
+++ b/lib/vita/slab.c
@@ -2,7 +2,6 @@
 
 #include "slab.h"
 
-#include <math.h>
 #include <stdint.h>
 #include <stddef.h>
 
@@ -49,6 +48,18 @@ static int sce_exe_free(SceUID write_res, SceUID exe_res) {
     return 0;
 }
 
+static inline uint32_t next_pow_2(uint32_t v) {
+    v--;
+    v |= v >> 1;
+    v |= v >> 2;
+    v |= v >> 4;
+    v |= v >> 8;
+    v |= v >> 16;
+    v++;
+    v += (v == 0);
+    return v;
+}
+
 void slab_init(struct slab_chain *const sch, const size_t itemsize, SceUID pid)
 {
     assert(sch != NULL);
@@ -60,7 +71,7 @@ void slab_init(struct slab_chain *const sch, const size_t itemsize, SceUID pid)
 
     const size_t data_offset = offsetof(struct slab_header, data);
     const size_t least_slabsize = data_offset + 64 * sch->itemsize;
-    sch->slabsize = (size_t) 1 << (size_t) ceil(log2(least_slabsize));
+    sch->slabsize = (size_t) next_pow_2(least_slabsize);
     sch->itemcount = 64;
 
     if (sch->slabsize - least_slabsize != 0) {
diff --git a/lib/vita/slab.h b/lib/vita/slab.h
index 942eb70..c8c5d9b 100755
--- a/lib/vita/slab.h
+++ b/lib/vita/slab.h
@@ -32,7 +32,7 @@ struct slab_chain {
     SceUID pid;
 };
 
-void slab_init(struct slab_chain *, size_t);
+void slab_init(struct slab_chain *, size_t, SceUID);
 void *slab_alloc(struct slab_chain *, uintptr_t *);
 void slab_free(struct slab_chain *, const void *);
 void slab_traverse(const struct slab_chain *, void (*)(const void *));