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-rw-r--r--include/linux/decompress/mm.h102
1 files changed, 102 insertions, 0 deletions
diff --git a/include/linux/decompress/mm.h b/include/linux/decompress/mm.h
new file mode 100644
index 000000000..9192986b1
--- /dev/null
+++ b/include/linux/decompress/mm.h
@@ -0,0 +1,102 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * linux/compr_mm.h
+ *
+ * Memory management for pre-boot and ramdisk uncompressors
+ *
+ * Authors: Alain Knaff <alain@knaff.lu>
+ *
+ */
+
+#ifndef DECOMPR_MM_H
+#define DECOMPR_MM_H
+
+#ifdef STATIC
+
+/* Code active when included from pre-boot environment: */
+
+/*
+ * Some architectures want to ensure there is no local data in their
+ * pre-boot environment, so that data can arbitrarily relocated (via
+ * GOT references). This is achieved by defining STATIC_RW_DATA to
+ * be null.
+ */
+#ifndef STATIC_RW_DATA
+#define STATIC_RW_DATA static
+#endif
+
+/*
+ * When an architecture needs to share the malloc()/free() implementation
+ * between compilation units, it needs to have non-local visibility.
+ */
+#ifndef MALLOC_VISIBLE
+#define MALLOC_VISIBLE static
+#endif
+
+/* A trivial malloc implementation, adapted from
+ * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
+ */
+STATIC_RW_DATA unsigned long malloc_ptr;
+STATIC_RW_DATA int malloc_count;
+
+MALLOC_VISIBLE void *malloc(int size)
+{
+ void *p;
+
+ if (size < 0)
+ return NULL;
+ if (!malloc_ptr)
+ malloc_ptr = free_mem_ptr;
+
+ malloc_ptr = (malloc_ptr + 3) & ~3; /* Align */
+
+ p = (void *)malloc_ptr;
+ malloc_ptr += size;
+
+ if (free_mem_end_ptr && malloc_ptr >= free_mem_end_ptr)
+ return NULL;
+
+ malloc_count++;
+ return p;
+}
+
+MALLOC_VISIBLE void free(void *where)
+{
+ malloc_count--;
+ if (!malloc_count)
+ malloc_ptr = free_mem_ptr;
+}
+
+#define large_malloc(a) malloc(a)
+#define large_free(a) free(a)
+
+#define INIT
+
+#else /* STATIC */
+
+/* Code active when compiled standalone for use when loading ramdisk: */
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+/* Use defines rather than static inline in order to avoid spurious
+ * warnings when not needed (indeed large_malloc / large_free are not
+ * needed by inflate */
+
+#define malloc(a) kmalloc(a, GFP_KERNEL)
+#define free(a) kfree(a)
+
+#define large_malloc(a) vmalloc(a)
+#define large_free(a) vfree(a)
+
+#define INIT __init
+#define STATIC
+
+#include <linux/init.h>
+
+#endif /* STATIC */
+
+#endif /* DECOMPR_MM_H */