aboutsummaryrefslogtreecommitdiff
path: root/fs/proc/task_nommu.c
blob: 1ccfa537f5f5dfaac3c1351dabe391f0ca3e6d22 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318

#include <linux/mm.h>
#include <linux/file.h>
#include <linux/fdtable.h>
#include <linux/fs_struct.h>
#include <linux/mount.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include "internal.h"

/*
 * Logic: we've got two memory sums for each process, "shared", and
 * "non-shared". Shared memory may get counted more than once, for
 * each process that owns it. Non-shared memory is counted
 * accurately.
 */
void task_mem(struct seq_file *m, struct mm_struct *mm)
{
	struct vm_area_struct *vma;
	struct vm_region *region;
	struct rb_node *p;
	unsigned long bytes = 0, sbytes = 0, slack = 0, size;
        
	down_read(&mm->mmap_sem);
	for (p = rb_first(&mm->mm_rb); p; p = rb_next(p)) {
		vma = rb_entry(p, struct vm_area_struct, vm_rb);

		bytes += kobjsize(vma);

		region = vma->vm_region;
		if (region) {
			size = kobjsize(region);
			size += region->vm_end - region->vm_start;
		} else {
			size = vma->vm_end - vma->vm_start;
		}

		if (atomic_read(&mm->mm_count) > 1 ||
		    vma->vm_flags & VM_MAYSHARE) {
			sbytes += size;
		} else {
			bytes += size;
			if (region)
				slack = region->vm_end - vma->vm_end;
		}
	}

	if (atomic_read(&mm->mm_count) > 1)
		sbytes += kobjsize(mm);
	else
		bytes += kobjsize(mm);
	
	if (current->fs && current->fs->users > 1)
		sbytes += kobjsize(current->fs);
	else
		bytes += kobjsize(current->fs);

	if (current->files && atomic_read(&current->files->count) > 1)
		sbytes += kobjsize(current->files);
	else
		bytes += kobjsize(current->files);

	if (current->sighand && atomic_read(&current->sighand->count) > 1)
		sbytes += kobjsize(current->sighand);
	else
		bytes += kobjsize(current->sighand);

	bytes += kobjsize(current); /* includes kernel stack */

	seq_printf(m,
		"Mem:\t%8lu bytes\n"
		"Slack:\t%8lu bytes\n"
		"Shared:\t%8lu bytes\n",
		bytes, slack, sbytes);

	up_read(&mm->mmap_sem);
}

unsigned long task_vsize(struct mm_struct *mm)
{
	struct vm_area_struct *vma;
	struct rb_node *p;
	unsigned long vsize = 0;

	down_read(&mm->mmap_sem);
	for (p = rb_first(&mm->mm_rb); p; p = rb_next(p)) {
		vma = rb_entry(p, struct vm_area_struct, vm_rb);
		vsize += vma->vm_end - vma->vm_start;
	}
	up_read(&mm->mmap_sem);
	return vsize;
}

unsigned long task_statm(struct mm_struct *mm,
			 unsigned long *shared, unsigned long *text,
			 unsigned long *data, unsigned long *resident)
{
	struct vm_area_struct *vma;
	struct vm_region *region;
	struct rb_node *p;
	unsigned long size = kobjsize(mm);

	down_read(&mm->mmap_sem);
	for (p = rb_first(&mm->mm_rb); p; p = rb_next(p)) {
		vma = rb_entry(p, struct vm_area_struct, vm_rb);
		size += kobjsize(vma);
		region = vma->vm_region;
		if (region) {
			size += kobjsize(region);
			size += region->vm_end - region->vm_start;
		}
	}

	*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
		>> PAGE_SHIFT;
	*data = (PAGE_ALIGN(mm->start_stack) - (mm->start_data & PAGE_MASK))
		>> PAGE_SHIFT;
	up_read(&mm->mmap_sem);
	size >>= PAGE_SHIFT;
	size += *text + *data;
	*resident = size;
	return size;
}

static void pad_len_spaces(struct seq_file *m, int len)
{
	len = 25 + sizeof(void*) * 6 - len;
	if (len < 1)
		len = 1;
	seq_printf(m, "%*c", len, ' ');
}

/*
 * display a single VMA to a sequenced file
 */
static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma,
			  int is_pid)
{
	struct mm_struct *mm = vma->vm_mm;
	struct proc_maps_private *priv = m->private;
	unsigned long ino = 0;
	struct file *file;
	dev_t dev = 0;
	int flags, len;
	unsigned long long pgoff = 0;

	flags = vma->vm_flags;
	file = vma->vm_file;

	if (file) {
		struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
		dev = inode->i_sb->s_dev;
		ino = inode->i_ino;
		pgoff = (loff_t)vma->vm_pgoff << PAGE_SHIFT;
	}

	seq_printf(m,
		   "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
		   vma->vm_start,
		   vma->vm_end,
		   flags & VM_READ ? 'r' : '-',
		   flags & VM_WRITE ? 'w' : '-',
		   flags & VM_EXEC ? 'x' : '-',
		   flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p',
		   pgoff,
		   MAJOR(dev), MINOR(dev), ino, &len);

	if (file) {
		pad_len_spaces(m, len);
		seq_path(m, &file->f_path, "");
	} else if (mm) {
		pid_t tid = vm_is_stack(priv->task, vma, is_pid);

		if (tid != 0) {
			pad_len_spaces(m, len);
			/*
			 * Thread stack in /proc/PID/task/TID/maps or
			 * the main process stack.
			 */
			if (!is_pid || (vma->vm_start <= mm->start_stack &&
			    vma->vm_end >= mm->start_stack))
				seq_printf(m, "[stack]");
			else
				seq_printf(m, "[stack:%d]", tid);
		}
	}

	seq_putc(m, '\n');
	return 0;
}

/*
 * display mapping lines for a particular process's /proc/pid/maps
 */
static int show_map(struct seq_file *m, void *_p, int is_pid)
{
	struct rb_node *p = _p;

	return nommu_vma_show(m, rb_entry(p, struct vm_area_struct, vm_rb),
			      is_pid);
}

static int show_pid_map(struct seq_file *m, void *_p)
{
	return show_map(m, _p, 1);
}

static int show_tid_map(struct seq_file *m, void *_p)
{
	return show_map(m, _p, 0);
}

static void *m_start(struct seq_file *m, loff_t *pos)
{
	struct proc_maps_private *priv = m->private;
	struct mm_struct *mm;
	struct rb_node *p;
	loff_t n = *pos;

	/* pin the task and mm whilst we play with them */
	priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
	if (!priv->task)
		return ERR_PTR(-ESRCH);

	mm = mm_access(priv->task, PTRACE_MODE_READ);
	if (!mm || IS_ERR(mm)) {
		put_task_struct(priv->task);
		priv->task = NULL;
		return mm;
	}
	down_read(&mm->mmap_sem);

	/* start from the Nth VMA */
	for (p = rb_first(&mm->mm_rb); p; p = rb_next(p))
		if (n-- == 0)
			return p;
	return NULL;
}

static void m_stop(struct seq_file *m, void *_vml)
{
	struct proc_maps_private *priv = m->private;

	if (priv->task) {
		struct mm_struct *mm = priv->task->mm;
		up_read(&mm->mmap_sem);
		mmput(mm);
		put_task_struct(priv->task);
	}
}

static void *m_next(struct seq_file *m, void *_p, loff_t *pos)
{
	struct rb_node *p = _p;

	(*pos)++;
	return p ? rb_next(p) : NULL;
}

static const struct seq_operations proc_pid_maps_ops = {
	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
	.show	= show_pid_map
};

static const struct seq_operations proc_tid_maps_ops = {
	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
	.show	= show_tid_map
};

static int maps_open(struct inode *inode, struct file *file,
		     const struct seq_operations *ops)
{
	struct proc_maps_private *priv;
	int ret = -ENOMEM;

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (priv) {
		priv->pid = proc_pid(inode);
		ret = seq_open(file, ops);
		if (!ret) {
			struct seq_file *m = file->private_data;
			m->private = priv;
		} else {
			kfree(priv);
		}
	}
	return ret;
}

static int pid_maps_open(struct inode *inode, struct file *file)
{
	return maps_open(inode, file, &proc_pid_maps_ops);
}

static int tid_maps_open(struct inode *inode, struct file *file)
{
	return maps_open(inode, file, &proc_tid_maps_ops);
}

const struct file_operations proc_pid_maps_operations = {
	.open		= pid_maps_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release_private,
};

const struct file_operations proc_tid_maps_operations = {
	.open		= tid_maps_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release_private,
};