backported fixes from 256boss

[bootcensus] / src / mem.h

diff --git a/src/mem.h b/src/mem.h
index 219bf5f..40de366 100644 (file)
--- a/src/mem.h
+++ b/src/mem.h
@@ -1,6 +1,48 @@
+/*
+pcboot - bootable PC demo/game kernel
+Copyright (C) 2018  John Tsiombikas <nuclear@member.fsf.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY, without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
 #ifndef MEM_H_
 #define MEM_H_
 
+#define ADDR_TO_PAGE(x)                        ((uint32_t)(x) >> 12)
+#define PAGE_TO_ADDR(x)                        ((uint32_t)(x) << 12)
+#define PAGE_TO_PTR(x)                 ((void*)PAGE_TO_ADDR(x))
+
+#define BYTES_TO_PAGES(x)              (((uint32_t)(x) + 4095) >> 12)
+
+/* for alloc_ppage/alloc_ppages */
+enum {
+       MEM_HEAP = 0,   /* start searching from the bottom */
+       MEM_STACK = 1   /* start searching from the top */
+};
+
 void init_mem(void);
 
+int alloc_ppage(int area);
+void free_ppage(int pg);
+
+/* allocate a number of consecutive pages */
+int alloc_ppages(int count, int area);
+void free_ppages(int pg0, int count);
+
+/* allocate a specific range of pages.
+ * Fails (and returns -1) if any page in the requested range is not free.
+ */
+int alloc_ppage_range(int start, int size);
+int free_ppage_range(int start, int size);
+
 #endif /* MEM_H_ */