Staging
v0.7.0
v0.7.0
https://github.com/torvalds/linux
Tip revision: a111daf0c53ae91e71fd2bfe7497862d14132e3e authored by Linus Torvalds on 19 June 2022, 20:06:47 UTC
Linux 5.19-rc3
Linux 5.19-rc3
Tip revision: a111daf
proc_powerpc.c
// 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);