1 /* 2 * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen IBM Corporation 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 17 */ 18 19 #include <linux/init.h> 20 #include <linux/mm.h> 21 #include <linux/proc_fs.h> 22 #include <linux/kernel.h> 23 24 #include <asm/machdep.h> 25 #include <asm/vdso_datapage.h> 26 #include <asm/rtas.h> 27 #include <asm/uaccess.h> 28 #include <asm/prom.h> 29 30 #ifdef CONFIG_PPC64 31 32 static loff_t page_map_seek( struct file *file, loff_t off, int whence) 33 { 34 loff_t new; 35 struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode); 36 37 switch(whence) { 38 case 0: 39 new = off; 40 break; 41 case 1: 42 new = file->f_pos + off; 43 break; 44 case 2: 45 new = dp->size + off; 46 break; 47 default: 48 return -EINVAL; 49 } 50 if ( new < 0 || new > dp->size ) 51 return -EINVAL; 52 return (file->f_pos = new); 53 } 54 55 static ssize_t page_map_read( struct file *file, char __user *buf, size_t nbytes, 56 loff_t *ppos) 57 { 58 struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode); 59 return simple_read_from_buffer(buf, nbytes, ppos, dp->data, dp->size); 60 } 61 62 static int page_map_mmap( struct file *file, struct vm_area_struct *vma ) 63 { 64 struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode); 65 66 if ((vma->vm_end - vma->vm_start) > dp->size) 67 return -EINVAL; 68 69 remap_pfn_range(vma, vma->vm_start, __pa(dp->data) >> PAGE_SHIFT, 70 dp->size, vma->vm_page_prot); 71 return 0; 72 } 73 74 static const struct file_operations page_map_fops = { 75 .llseek = page_map_seek, 76 .read = page_map_read, 77 .mmap = page_map_mmap 78 }; 79 80 81 static int __init proc_ppc64_init(void) 82 { 83 struct proc_dir_entry *pde; 84 85 pde = proc_create_data("powerpc/systemcfg", S_IFREG|S_IRUGO, NULL, 86 &page_map_fops, vdso_data); 87 if (!pde) 88 return 1; 89 pde->size = PAGE_SIZE; 90 91 return 0; 92 } 93 __initcall(proc_ppc64_init); 94 95 #endif /* CONFIG_PPC64 */ 96 97 /* 98 * Create the ppc64 and ppc64/rtas directories early. This allows us to 99 * assume that they have been previously created in drivers. 100 */ 101 static int __init proc_ppc64_create(void) 102 { 103 struct proc_dir_entry *root; 104 105 root = proc_mkdir("powerpc", NULL); 106 if (!root) 107 return 1; 108 109 #ifdef CONFIG_PPC64 110 if (!proc_symlink("ppc64", NULL, "powerpc")) 111 pr_err("Failed to create link /proc/ppc64 -> /proc/powerpc\n"); 112 #endif 113 114 if (!of_find_node_by_path("/rtas")) 115 return 0; 116 117 if (!proc_mkdir("rtas", root)) 118 return 1; 119 120 if (!proc_symlink("rtas", NULL, "powerpc/rtas")) 121 return 1; 122 123 return 0; 124 } 125 core_initcall(proc_ppc64_create); 126