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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /include/asm-generic/memory_model.h
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/asm-generic/memory_model.h')
-rw-r--r--include/asm-generic/memory_model.h57
1 files changed, 57 insertions, 0 deletions
diff --git a/include/asm-generic/memory_model.h b/include/asm-generic/memory_model.h
new file mode 100644
index 000000000..a2c8ed602
--- /dev/null
+++ b/include/asm-generic/memory_model.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_MEMORY_MODEL_H
+#define __ASM_MEMORY_MODEL_H
+
+#include <linux/pfn.h>
+
+#ifndef __ASSEMBLY__
+
+/*
+ * supports 3 memory models.
+ */
+#if defined(CONFIG_FLATMEM)
+
+#ifndef ARCH_PFN_OFFSET
+#define ARCH_PFN_OFFSET (0UL)
+#endif
+
+#define __pfn_to_page(pfn) (mem_map + ((pfn) - ARCH_PFN_OFFSET))
+#define __page_to_pfn(page) ((unsigned long)((page) - mem_map) + \
+ ARCH_PFN_OFFSET)
+
+#elif defined(CONFIG_SPARSEMEM_VMEMMAP)
+
+/* memmap is virtually contiguous. */
+#define __pfn_to_page(pfn) (vmemmap + (pfn))
+#define __page_to_pfn(page) (unsigned long)((page) - vmemmap)
+
+#elif defined(CONFIG_SPARSEMEM)
+/*
+ * Note: section's mem_map is encoded to reflect its start_pfn.
+ * section[i].section_mem_map == mem_map's address - start_pfn;
+ */
+#define __page_to_pfn(pg) \
+({ const struct page *__pg = (pg); \
+ int __sec = page_to_section(__pg); \
+ (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \
+})
+
+#define __pfn_to_page(pfn) \
+({ unsigned long __pfn = (pfn); \
+ struct mem_section *__sec = __pfn_to_section(__pfn); \
+ __section_mem_map_addr(__sec) + __pfn; \
+})
+#endif /* CONFIG_FLATMEM/SPARSEMEM */
+
+/*
+ * Convert a physical address to a Page Frame Number and back
+ */
+#define __phys_to_pfn(paddr) PHYS_PFN(paddr)
+#define __pfn_to_phys(pfn) PFN_PHYS(pfn)
+
+#define page_to_pfn __page_to_pfn
+#define pfn_to_page __pfn_to_page
+
+#endif /* __ASSEMBLY__ */
+
+#endif