4 files changed, 66 insertions, 3 deletions
diff --git a/lib/libjove/arch/x86_64/pager/ensure.c b/lib/libjove/arch/x86_64/pager/ensure.c
index bfe68ff..874db35 100644
--- a/lib/libjove/arch/x86_64/pager/ensure.c
+++ b/lib/libjove/arch/x86_64/pager/ensure.c
@@ -18,7 +18,7 @@ pager_write_path(uintptr_t vptr, uint8_t depth)
     if(depth >= 4) return -1;
 
     uint16_t *path = (uint16_t*)&r;
-    for(uint8_t i = 0; i < depth; i++) path[i] = PMLI_DL(vptr, i);
+    for(uint8_t i = 0; i < depth + 1; i++) path[i] = PMLI_DL(vptr, i);
     return r;
 }
 
@@ -70,10 +70,10 @@ pager_ensure_at_depth(KernelObjectPageMap *map, uint8_t depth, uint16_t *path)
 JoveError
 jove_pager_ensure_for(KernelObjectPageMap *map, uintptr_t vptr)
 {
+    vptr &= ~0xFFFULL;
+
     uint64_t path = pager_write_path(vptr, 3);
     if(path == -1) return EJOVE_BADARG;
-
-    vptr &= ~0xFFFULL;
     uint16_t *path_seg = (uint16_t*)&path;
 
     jove_kprintf("%p Alloc %p : %x:%x:%x:%x\n", map, vptr, path_seg[0], path_seg[1], path_seg[2], path_seg[3]);
@@ -86,3 +86,25 @@ jove_pager_ensure_for(KernelObjectPageMap *map, uintptr_t vptr)
     }
     return EJOVE_OK;
 }
+
+#define PAGER_CACHE_EXISTS_DEPTH(map, path_seg, d) \
+    if(path_seg[d] != d_cache[d]) { \
+        if(!jove_pagemap_exists(map, d, path_seg)) return 0; \
+        d_cache[d] = path_seg[d]; \
+    }
+
+
+int
+jove_pager_exists_for(KernelObjectPageMap *map, uintptr_t vptr)
+{
+    vptr &= ~0xFFFULL;
+
+    uint64_t path = pager_write_path(vptr, 3);
+    if(path == -1) return EJOVE_BADARG;
+    uint16_t *path_seg = (uint16_t*)&path;
+
+    PAGER_CACHE_EXISTS_DEPTH(map, path_seg, 0);
+    PAGER_CACHE_EXISTS_DEPTH(map, path_seg, 1);
+    PAGER_CACHE_EXISTS_DEPTH(map, path_seg, 2);
+    return jove_pagemap_exists(map, 3, path_seg);
+}
diff --git a/lib/libjove/include/arch/x86_64/pager.h b/lib/libjove/include/arch/x86_64/pager.h
index 7e47ed1..2a53a07 100644
--- a/lib/libjove/include/arch/x86_64/pager.h
+++ b/lib/libjove/include/arch/x86_64/pager.h
@@ -9,4 +9,7 @@ extern KernelObjectPageMap __jove_pagemap;
 JoveError jove_pager_ensure_for(KernelObjectPageMap *map, uintptr_t vptr);
 #define jove_pager_ensure(vptr) jove_pager_ensure_for(&__jove_pagemap, vptr)
 
+int jove_pager_exists_for(KernelObjectPageMap *map, uintptr_t vptr);
+#define jove_pager_exists(vptr) jove_pager_exists_for(&__jove_pagemap, vptr);
+
 #endif
diff --git a/lib/libjove/include/memory.h b/lib/libjove/include/memory.h
new file mode 100644
index 0000000..9d4ce1d
--- /dev/null
+++ b/lib/libjove/include/memory.h
@@ -0,0 +1,15 @@
+#ifndef _LIBJOVE_MEMORY_H
+#define _LIBJOVE_MEMORY_H 1
+
+#include <jove/error.h>
+
+#ifdef __x86_64__
+#include <jove/arch/x86_64/pager.h>
+#define jove_mem_ensure(vptr) jove_pager_ensure(vptr)
+#define jove_mem_exists(vptr) jove_pager_exists(vptr)
+#endif
+
+JoveError jove_mem_ensure_range(uintptr_t start, uintptr_t end);
+JoveError jove_mem_ensure_w(uintptr_t start, size_t pages);
+
+#endif
diff --git a/lib/libjove/memory.c b/lib/libjove/memory.c
new file mode 100644
index 0000000..db76528
--- /dev/null
+++ b/lib/libjove/memory.c
@@ -0,0 +1,23 @@
+#include <jove/memory.h>
+
+JoveError 
+jove_mem_ensure_w(uintptr_t start, size_t pages)
+{
+    start &= ~0xFFFULL;
+    for(size_t i = 0; i < pages; i++) {
+        uintptr_t at = start + (i << 12);
+        JoveError e = jove_mem_ensure(at);
+        if(e) return e;
+    }
+    return EJOVE_OK;
+}
+
+JoveError
+jove_mem_ensure_range(uintptr_t start, uintptr_t end)
+{
+    start &= ~0xFFFULL;
+    if(end & 0xFFF)
+        end += 0x1000 - (end & 0xFFF);
+
+    return jove_mem_ensure_w(start, (end - start) >> 12);
+}