powerpc: Move /proc/ppc64 to /proc/powerpc and add symlink

Some of the stuff in /proc/ppc64 such as the RTAS bits are actually
useful to some 32-bit platforms. Rename the file, and create a
symlink on 64-bit for backward compatibility

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 126 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/proc_powerpc.c b/arch/powerpc/kernel/proc_powerpc.c
new file mode 100644
index 000000000000..1ed3b8d7981e
--- /dev/null
+++ b/arch/powerpc/kernel/proc_powerpc.c
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen IBM Corporation
+ *
+ * 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 2 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+
+#include <asm/machdep.h>
+#include <asm/vdso_datapage.h>
+#include <asm/rtas.h>
+#include <asm/uaccess.h>
+#include <asm/prom.h>
+
+#ifdef CONFIG_PPC64
+
+static loff_t page_map_seek( struct file *file, loff_t off, int whence)
+{
+	loff_t new;
+	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
+
+	switch(whence) {
+	case 0:
+		new = off;
+		break;
+	case 1:
+		new = file->f_pos + off;
+		break;
+	case 2:
+		new = dp->size + off;
+		break;
+	default:
+		return -EINVAL;
+	}
+	if ( new < 0 || new > dp->size )
+		return -EINVAL;
+	return (file->f_pos = new);
+}
+
+static ssize_t page_map_read( struct file *file, char __user *buf, size_t nbytes,
+			      loff_t *ppos)
+{
+	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
+	return simple_read_from_buffer(buf, nbytes, ppos, dp->data, dp->size);
+}
+
+static int page_map_mmap( struct file *file, struct vm_area_struct *vma )
+{
+	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
+
+	if ((vma->vm_end - vma->vm_start) > dp->size)
+		return -EINVAL;
+
+	remap_pfn_range(vma, vma->vm_start, __pa(dp->data) >> PAGE_SHIFT,
+						dp->size, vma->vm_page_prot);
+	return 0;
+}
+
+static const struct file_operations page_map_fops = {
+	.llseek	= page_map_seek,
+	.read	= page_map_read,
+	.mmap	= page_map_mmap
+};
+
+
+static int __init proc_ppc64_init(void)
+{
+	struct proc_dir_entry *pde;
+
+	pde = proc_create_data("powerpc/systemcfg", S_IFREG|S_IRUGO, NULL,
+			       &page_map_fops, vdso_data);
+	if (!pde)
+		return 1;
+	pde->size = 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);