1 2 #include <linux/mm.h> 3 #include <linux/file.h> 4 #include <linux/fdtable.h> 5 #include <linux/fs_struct.h> 6 #include <linux/mount.h> 7 #include <linux/ptrace.h> 8 #include <linux/slab.h> 9 #include <linux/seq_file.h> 10 #include <linux/sched/mm.h> 11 12 #include "internal.h" 13 14 /* 15 * Logic: we've got two memory sums for each process, "shared", and 16 * "non-shared". Shared memory may get counted more than once, for 17 * each process that owns it. Non-shared memory is counted 18 * accurately. 19 */ 20 void task_mem(struct seq_file *m, struct mm_struct *mm) 21 { 22 struct vm_area_struct *vma; 23 struct vm_region *region; 24 struct rb_node *p; 25 unsigned long bytes = 0, sbytes = 0, slack = 0, size; 26 27 down_read(&mm->mmap_sem); 28 for (p = rb_first(&mm->mm_rb); p; p = rb_next(p)) { 29 vma = rb_entry(p, struct vm_area_struct, vm_rb); 30 31 bytes += kobjsize(vma); 32 33 region = vma->vm_region; 34 if (region) { 35 size = kobjsize(region); 36 size += region->vm_end - region->vm_start; 37 } else { 38 size = vma->vm_end - vma->vm_start; 39 } 40 41 if (atomic_read(&mm->mm_count) > 1 || 42 vma->vm_flags & VM_MAYSHARE) { 43 sbytes += size; 44 } else { 45 bytes += size; 46 if (region) 47 slack = region->vm_end - vma->vm_end; 48 } 49 } 50 51 if (atomic_read(&mm->mm_count) > 1) 52 sbytes += kobjsize(mm); 53 else 54 bytes += kobjsize(mm); 55 56 if (current->fs && current->fs->users > 1) 57 sbytes += kobjsize(current->fs); 58 else 59 bytes += kobjsize(current->fs); 60 61 if (current->files && atomic_read(¤t->files->count) > 1) 62 sbytes += kobjsize(current->files); 63 else 64 bytes += kobjsize(current->files); 65 66 if (current->sighand && atomic_read(¤t->sighand->count) > 1) 67 sbytes += kobjsize(current->sighand); 68 else 69 bytes += kobjsize(current->sighand); 70 71 bytes += kobjsize(current); /* includes kernel stack */ 72 73 seq_printf(m, 74 "Mem:\t%8lu bytes\n" 75 "Slack:\t%8lu bytes\n" 76 "Shared:\t%8lu bytes\n", 77 bytes, slack, sbytes); 78 79 up_read(&mm->mmap_sem); 80 } 81 82 unsigned long task_vsize(struct mm_struct *mm) 83 { 84 struct vm_area_struct *vma; 85 struct rb_node *p; 86 unsigned long vsize = 0; 87 88 down_read(&mm->mmap_sem); 89 for (p = rb_first(&mm->mm_rb); p; p = rb_next(p)) { 90 vma = rb_entry(p, struct vm_area_struct, vm_rb); 91 vsize += vma->vm_end - vma->vm_start; 92 } 93 up_read(&mm->mmap_sem); 94 return vsize; 95 } 96 97 unsigned long task_statm(struct mm_struct *mm, 98 unsigned long *shared, unsigned long *text, 99 unsigned long *data, unsigned long *resident) 100 { 101 struct vm_area_struct *vma; 102 struct vm_region *region; 103 struct rb_node *p; 104 unsigned long size = kobjsize(mm); 105 106 down_read(&mm->mmap_sem); 107 for (p = rb_first(&mm->mm_rb); p; p = rb_next(p)) { 108 vma = rb_entry(p, struct vm_area_struct, vm_rb); 109 size += kobjsize(vma); 110 region = vma->vm_region; 111 if (region) { 112 size += kobjsize(region); 113 size += region->vm_end - region->vm_start; 114 } 115 } 116 117 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 118 >> PAGE_SHIFT; 119 *data = (PAGE_ALIGN(mm->start_stack) - (mm->start_data & PAGE_MASK)) 120 >> PAGE_SHIFT; 121 up_read(&mm->mmap_sem); 122 size >>= PAGE_SHIFT; 123 size += *text + *data; 124 *resident = size; 125 return size; 126 } 127 128 static int is_stack(struct proc_maps_private *priv, 129 struct vm_area_struct *vma) 130 { 131 struct mm_struct *mm = vma->vm_mm; 132 133 /* 134 * We make no effort to guess what a given thread considers to be 135 * its "stack". It's not even well-defined for programs written 136 * languages like Go. 137 */ 138 return vma->vm_start <= mm->start_stack && 139 vma->vm_end >= mm->start_stack; 140 } 141 142 /* 143 * display a single VMA to a sequenced file 144 */ 145 static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma, 146 int is_pid) 147 { 148 struct mm_struct *mm = vma->vm_mm; 149 struct proc_maps_private *priv = m->private; 150 unsigned long ino = 0; 151 struct file *file; 152 dev_t dev = 0; 153 int flags; 154 unsigned long long pgoff = 0; 155 156 flags = vma->vm_flags; 157 file = vma->vm_file; 158 159 if (file) { 160 struct inode *inode = file_inode(vma->vm_file); 161 dev = inode->i_sb->s_dev; 162 ino = inode->i_ino; 163 pgoff = (loff_t)vma->vm_pgoff << PAGE_SHIFT; 164 } 165 166 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 167 seq_printf(m, 168 "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ", 169 vma->vm_start, 170 vma->vm_end, 171 flags & VM_READ ? 'r' : '-', 172 flags & VM_WRITE ? 'w' : '-', 173 flags & VM_EXEC ? 'x' : '-', 174 flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p', 175 pgoff, 176 MAJOR(dev), MINOR(dev), ino); 177 178 if (file) { 179 seq_pad(m, ' '); 180 seq_file_path(m, file, ""); 181 } else if (mm && is_stack(priv, vma)) { 182 seq_pad(m, ' '); 183 seq_printf(m, "[stack]"); 184 } 185 186 seq_putc(m, '\n'); 187 return 0; 188 } 189 190 /* 191 * display mapping lines for a particular process's /proc/pid/maps 192 */ 193 static int show_map(struct seq_file *m, void *_p, int is_pid) 194 { 195 struct rb_node *p = _p; 196 197 return nommu_vma_show(m, rb_entry(p, struct vm_area_struct, vm_rb), 198 is_pid); 199 } 200 201 static int show_pid_map(struct seq_file *m, void *_p) 202 { 203 return show_map(m, _p, 1); 204 } 205 206 static int show_tid_map(struct seq_file *m, void *_p) 207 { 208 return show_map(m, _p, 0); 209 } 210 211 static void *m_start(struct seq_file *m, loff_t *pos) 212 { 213 struct proc_maps_private *priv = m->private; 214 struct mm_struct *mm; 215 struct rb_node *p; 216 loff_t n = *pos; 217 218 /* pin the task and mm whilst we play with them */ 219 priv->task = get_proc_task(priv->inode); 220 if (!priv->task) 221 return ERR_PTR(-ESRCH); 222 223 mm = priv->mm; 224 if (!mm || !mmget_not_zero(mm)) 225 return NULL; 226 227 down_read(&mm->mmap_sem); 228 /* start from the Nth VMA */ 229 for (p = rb_first(&mm->mm_rb); p; p = rb_next(p)) 230 if (n-- == 0) 231 return p; 232 233 up_read(&mm->mmap_sem); 234 mmput(mm); 235 return NULL; 236 } 237 238 static void m_stop(struct seq_file *m, void *_vml) 239 { 240 struct proc_maps_private *priv = m->private; 241 242 if (!IS_ERR_OR_NULL(_vml)) { 243 up_read(&priv->mm->mmap_sem); 244 mmput(priv->mm); 245 } 246 if (priv->task) { 247 put_task_struct(priv->task); 248 priv->task = NULL; 249 } 250 } 251 252 static void *m_next(struct seq_file *m, void *_p, loff_t *pos) 253 { 254 struct rb_node *p = _p; 255 256 (*pos)++; 257 return p ? rb_next(p) : NULL; 258 } 259 260 static const struct seq_operations proc_pid_maps_ops = { 261 .start = m_start, 262 .next = m_next, 263 .stop = m_stop, 264 .show = show_pid_map 265 }; 266 267 static const struct seq_operations proc_tid_maps_ops = { 268 .start = m_start, 269 .next = m_next, 270 .stop = m_stop, 271 .show = show_tid_map 272 }; 273 274 static int maps_open(struct inode *inode, struct file *file, 275 const struct seq_operations *ops) 276 { 277 struct proc_maps_private *priv; 278 279 priv = __seq_open_private(file, ops, sizeof(*priv)); 280 if (!priv) 281 return -ENOMEM; 282 283 priv->inode = inode; 284 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 285 if (IS_ERR(priv->mm)) { 286 int err = PTR_ERR(priv->mm); 287 288 seq_release_private(inode, file); 289 return err; 290 } 291 292 return 0; 293 } 294 295 296 static int map_release(struct inode *inode, struct file *file) 297 { 298 struct seq_file *seq = file->private_data; 299 struct proc_maps_private *priv = seq->private; 300 301 if (priv->mm) 302 mmdrop(priv->mm); 303 304 return seq_release_private(inode, file); 305 } 306 307 static int pid_maps_open(struct inode *inode, struct file *file) 308 { 309 return maps_open(inode, file, &proc_pid_maps_ops); 310 } 311 312 static int tid_maps_open(struct inode *inode, struct file *file) 313 { 314 return maps_open(inode, file, &proc_tid_maps_ops); 315 } 316 317 const struct file_operations proc_pid_maps_operations = { 318 .open = pid_maps_open, 319 .read = seq_read, 320 .llseek = seq_lseek, 321 .release = map_release, 322 }; 323 324 const struct file_operations proc_tid_maps_operations = { 325 .open = tid_maps_open, 326 .read = seq_read, 327 .llseek = seq_lseek, 328 .release = map_release, 329 }; 330 331