1 files changed, 93 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/proc_powerpc.c b/arch/powerpc/kernel/proc_powerpc.c
new file mode 100644
index 000000000..b109cd7b5
--- /dev/null
+++ b/arch/powerpc/kernel/proc_powerpc.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen IBM Corporation
+ */
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+
+#include <asm/machdep.h>
+#include <asm/vdso_datapage.h>
+#include <asm/rtas.h>
+#include <linux/uaccess.h>
+
+#ifdef CONFIG_PPC64
+
+static loff_t page_map_seek(struct file *file, loff_t off, int whence)
+{
+	return fixed_size_llseek(file, off, whence, PAGE_SIZE);
+}
+
+static ssize_t page_map_read( struct file *file, char __user *buf, size_t nbytes,
+			      loff_t *ppos)
+{
+	return simple_read_from_buffer(buf, nbytes, ppos,
+			pde_data(file_inode(file)), PAGE_SIZE);
+}
+
+static int page_map_mmap( struct file *file, struct vm_area_struct *vma )
+{
+	if ((vma->vm_end - vma->vm_start) > PAGE_SIZE)
+		return -EINVAL;
+
+	remap_pfn_range(vma, vma->vm_start,
+			__pa(pde_data(file_inode(file))) >> PAGE_SHIFT,
+			PAGE_SIZE, vma->vm_page_prot);
+	return 0;
+}
+
+static const struct proc_ops page_map_proc_ops = {
+	.proc_lseek	= page_map_seek,
+	.proc_read	= page_map_read,
+	.proc_mmap	= page_map_mmap,
+};
+
+
+static int __init proc_ppc64_init(void)
+{
+	struct proc_dir_entry *pde;
+
+	pde = proc_create_data("powerpc/systemcfg", S_IFREG | 0444, NULL,
+			       &page_map_proc_ops, vdso_data);
+	if (!pde)
+		return 1;
+	proc_set_size(pde, PAGE_SIZE);
+
+	return 0;
+}
+__initcall(proc_ppc64_init);
+
+#endif /* CONFIG_PPC64 */
+
+/*
+ * Create the ppc64 and ppc64/rtas directories early. This allows us to
+ * assume that they have been previously created in drivers.
+ */
+static int __init proc_ppc64_create(void)
+{
+	struct proc_dir_entry *root;
+
+	root = proc_mkdir("powerpc", NULL);
+	if (!root)
+		return 1;
+
+#ifdef CONFIG_PPC64
+	if (!proc_symlink("ppc64", NULL, "powerpc"))
+		pr_err("Failed to create link /proc/ppc64 -> /proc/powerpc\n");
+#endif
+
+	if (!of_find_node_by_path("/rtas"))
+		return 0;
+
+	if (!proc_mkdir("rtas", root))
+		return 1;
+
+	if (!proc_symlink("rtas", NULL, "powerpc/rtas"))
+		return 1;
+
+	return 0;
+}
+core_initcall(proc_ppc64_create);