1 /* nommu.c: mmu-less memory info files 2 * 3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. 4 * Written by David Howells (dhowells@redhat.com) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #include <linux/init.h> 13 #include <linux/module.h> 14 #include <linux/errno.h> 15 #include <linux/time.h> 16 #include <linux/kernel.h> 17 #include <linux/string.h> 18 #include <linux/mman.h> 19 #include <linux/proc_fs.h> 20 #include <linux/mm.h> 21 #include <linux/mmzone.h> 22 #include <linux/pagemap.h> 23 #include <linux/swap.h> 24 #include <linux/smp.h> 25 #include <linux/seq_file.h> 26 #include <linux/hugetlb.h> 27 #include <linux/vmalloc.h> 28 #include <asm/uaccess.h> 29 #include <asm/pgtable.h> 30 #include <asm/tlb.h> 31 #include <asm/div64.h> 32 #include "internal.h" 33 34 /* 35 * display a single region to a sequenced file 36 */ 37 static int nommu_region_show(struct seq_file *m, struct vm_region *region) 38 { 39 unsigned long ino = 0; 40 struct file *file; 41 dev_t dev = 0; 42 int flags, len; 43 44 flags = region->vm_flags; 45 file = region->vm_file; 46 47 if (file) { 48 struct inode *inode = file_inode(region->vm_file); 49 dev = inode->i_sb->s_dev; 50 ino = inode->i_ino; 51 } 52 53 seq_printf(m, 54 "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n", 55 region->vm_start, 56 region->vm_end, 57 flags & VM_READ ? 'r' : '-', 58 flags & VM_WRITE ? 'w' : '-', 59 flags & VM_EXEC ? 'x' : '-', 60 flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p', 61 ((loff_t)region->vm_pgoff) << PAGE_SHIFT, 62 MAJOR(dev), MINOR(dev), ino, &len); 63 64 if (file) { 65 len = 25 + sizeof(void *) * 6 - len; 66 if (len < 1) 67 len = 1; 68 seq_printf(m, "%*c", len, ' '); 69 seq_path(m, &file->f_path, ""); 70 } 71 72 seq_putc(m, '\n'); 73 return 0; 74 } 75 76 /* 77 * display a list of all the REGIONs the kernel knows about 78 * - nommu kernels have a single flat list 79 */ 80 static int nommu_region_list_show(struct seq_file *m, void *_p) 81 { 82 struct rb_node *p = _p; 83 84 return nommu_region_show(m, rb_entry(p, struct vm_region, vm_rb)); 85 } 86 87 static void *nommu_region_list_start(struct seq_file *m, loff_t *_pos) 88 { 89 struct rb_node *p; 90 loff_t pos = *_pos; 91 92 down_read(&nommu_region_sem); 93 94 for (p = rb_first(&nommu_region_tree); p; p = rb_next(p)) 95 if (pos-- == 0) 96 return p; 97 return NULL; 98 } 99 100 static void nommu_region_list_stop(struct seq_file *m, void *v) 101 { 102 up_read(&nommu_region_sem); 103 } 104 105 static void *nommu_region_list_next(struct seq_file *m, void *v, loff_t *pos) 106 { 107 (*pos)++; 108 return rb_next((struct rb_node *) v); 109 } 110 111 static const struct seq_operations proc_nommu_region_list_seqop = { 112 .start = nommu_region_list_start, 113 .next = nommu_region_list_next, 114 .stop = nommu_region_list_stop, 115 .show = nommu_region_list_show 116 }; 117 118 static int proc_nommu_region_list_open(struct inode *inode, struct file *file) 119 { 120 return seq_open(file, &proc_nommu_region_list_seqop); 121 } 122 123 static const struct file_operations proc_nommu_region_list_operations = { 124 .open = proc_nommu_region_list_open, 125 .read = seq_read, 126 .llseek = seq_lseek, 127 .release = seq_release, 128 }; 129 130 static int __init proc_nommu_init(void) 131 { 132 proc_create("maps", S_IRUGO, NULL, &proc_nommu_region_list_operations); 133 return 0; 134 } 135 136 module_init(proc_nommu_init); 137