xref: /linux/net/atm/proc.c (revision aa582dc25ace8951ad595c71fb93d21ed2ec4624)
1 // SPDX-License-Identifier: GPL-2.0
2 /* net/atm/proc.c - ATM /proc interface
3  *
4  * Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA
5  *
6  * seq_file api usage by romieu@fr.zoreil.com
7  *
8  * Evaluating the efficiency of the whole thing if left as an exercise to
9  * the reader.
10  */
11 
12 #include <linux/module.h> /* for EXPORT_SYMBOL */
13 #include <linux/string.h>
14 #include <linux/types.h>
15 #include <linux/mm.h>
16 #include <linux/fs.h>
17 #include <linux/stat.h>
18 #include <linux/proc_fs.h>
19 #include <linux/seq_file.h>
20 #include <linux/errno.h>
21 #include <linux/atm.h>
22 #include <linux/atmdev.h>
23 #include <linux/netdevice.h>
24 #include <linux/init.h> /* for __init */
25 #include <linux/slab.h>
26 #include <net/net_namespace.h>
27 #include <linux/uaccess.h>
28 #include <linux/param.h> /* for HZ */
29 #include <linux/atomic.h>
30 #include "resources.h"
31 #include "common.h" /* atm_proc_init prototype */
32 
33 static ssize_t proc_dev_atm_read(struct file *file, char __user *buf,
34 				 size_t count, loff_t *pos);
35 
36 static const struct proc_ops atm_dev_proc_ops = {
37 	.proc_read	= proc_dev_atm_read,
38 	.proc_lseek	= noop_llseek,
39 };
40 
41 static void add_stats(struct seq_file *seq, const char *aal,
42   const struct k_atm_aal_stats *stats)
43 {
44 	seq_printf(seq, "%s ( %d %d %d %d %d )", aal,
45 		   atomic_read(&stats->tx), atomic_read(&stats->tx_err),
46 		   atomic_read(&stats->rx), atomic_read(&stats->rx_err),
47 		   atomic_read(&stats->rx_drop));
48 }
49 
50 static void atm_dev_info(struct seq_file *seq, const struct atm_dev *dev)
51 {
52 	int i;
53 
54 	seq_printf(seq, "%3d %-8s", dev->number, dev->type);
55 	for (i = 0; i < ESI_LEN; i++)
56 		seq_printf(seq, "%02x", dev->esi[i]);
57 	seq_puts(seq, "  ");
58 	add_stats(seq, "0", &dev->stats.aal0);
59 	seq_puts(seq, "  ");
60 	add_stats(seq, "5", &dev->stats.aal5);
61 	seq_printf(seq, "\t[%d]", refcount_read(&dev->refcnt));
62 	seq_putc(seq, '\n');
63 }
64 
65 struct vcc_state {
66 	int bucket;
67 	struct sock *sk;
68 };
69 
70 static inline int compare_family(struct sock *sk, int family)
71 {
72 	return !family || (sk->sk_family == family);
73 }
74 
75 static int __vcc_walk(struct sock **sock, int family, int *bucket, loff_t l)
76 {
77 	struct sock *sk = *sock;
78 
79 	if (sk == SEQ_START_TOKEN) {
80 		for (*bucket = 0; *bucket < VCC_HTABLE_SIZE; ++*bucket) {
81 			struct hlist_head *head = &vcc_hash[*bucket];
82 
83 			sk = hlist_empty(head) ? NULL : __sk_head(head);
84 			if (sk)
85 				break;
86 		}
87 		l--;
88 	}
89 try_again:
90 	for (; sk; sk = sk_next(sk)) {
91 		l -= compare_family(sk, family);
92 		if (l < 0)
93 			goto out;
94 	}
95 	if (!sk && ++*bucket < VCC_HTABLE_SIZE) {
96 		sk = sk_head(&vcc_hash[*bucket]);
97 		goto try_again;
98 	}
99 	sk = SEQ_START_TOKEN;
100 out:
101 	*sock = sk;
102 	return (l < 0);
103 }
104 
105 static inline void *vcc_walk(struct seq_file *seq, loff_t l)
106 {
107 	struct vcc_state *state = seq->private;
108 	int family = (uintptr_t)(pde_data(file_inode(seq->file)));
109 
110 	return __vcc_walk(&state->sk, family, &state->bucket, l) ?
111 	       state : NULL;
112 }
113 
114 static void *vcc_seq_start(struct seq_file *seq, loff_t *pos)
115 	__acquires(vcc_sklist_lock)
116 {
117 	struct vcc_state *state = seq->private;
118 	loff_t left = *pos;
119 
120 	read_lock(&vcc_sklist_lock);
121 	state->sk = SEQ_START_TOKEN;
122 	return left ? vcc_walk(seq, left) : SEQ_START_TOKEN;
123 }
124 
125 static void vcc_seq_stop(struct seq_file *seq, void *v)
126 	__releases(vcc_sklist_lock)
127 {
128 	read_unlock(&vcc_sklist_lock);
129 }
130 
131 static void *vcc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
132 {
133 	v = vcc_walk(seq, 1);
134 	(*pos)++;
135 	return v;
136 }
137 
138 static void pvc_info(struct seq_file *seq, struct atm_vcc *vcc)
139 {
140 	static const char *const class_name[] = {
141 		"off", "UBR", "CBR", "VBR", "ABR"};
142 	static const char *const aal_name[] = {
143 		"---",	"1",	"2",	"3/4",	/*  0- 3 */
144 		"???",	"5",	"???",	"???",	/*  4- 7 */
145 		"???",	"???",	"???",	"???",	/*  8-11 */
146 		"???",	"0",	"???",	"???"};	/* 12-15 */
147 
148 	seq_printf(seq, "%3d %3d %5d %-3s %7d %-5s %7d %-6s",
149 		   vcc->dev->number, vcc->vpi, vcc->vci,
150 		   vcc->qos.aal >= ARRAY_SIZE(aal_name) ? "err" :
151 		   aal_name[vcc->qos.aal], vcc->qos.rxtp.min_pcr,
152 		   class_name[vcc->qos.rxtp.traffic_class],
153 		   vcc->qos.txtp.min_pcr,
154 		   class_name[vcc->qos.txtp.traffic_class]);
155 	seq_putc(seq, '\n');
156 }
157 
158 static void vcc_info(struct seq_file *seq, struct atm_vcc *vcc)
159 {
160 	struct sock *sk = sk_atm(vcc);
161 
162 	seq_printf(seq, "%pK ", vcc);
163 	if (!vcc->dev)
164 		seq_printf(seq, "Unassigned    ");
165 	else
166 		seq_printf(seq, "%3d %3d %5d ", vcc->dev->number, vcc->vpi,
167 			vcc->vci);
168 	switch (sk->sk_family) {
169 	case AF_ATMPVC:
170 		seq_printf(seq, "PVC");
171 		break;
172 	default:
173 		seq_printf(seq, "%3d", sk->sk_family);
174 	}
175 	seq_printf(seq, " %04lx  %5d %7d/%7d %7d/%7d [%d]\n",
176 		   vcc->flags, sk->sk_err,
177 		   sk_wmem_alloc_get(sk), sk->sk_sndbuf,
178 		   sk_rmem_alloc_get(sk), sk->sk_rcvbuf,
179 		   refcount_read(&sk->sk_refcnt));
180 }
181 
182 static int atm_dev_seq_show(struct seq_file *seq, void *v)
183 {
184 	static char atm_dev_banner[] =
185 		"Itf Type    ESI/\"MAC\"addr "
186 		"AAL(TX,err,RX,err,drop) ...               [refcnt]\n";
187 
188 	if (v == &atm_devs)
189 		seq_puts(seq, atm_dev_banner);
190 	else {
191 		struct atm_dev *dev = list_entry(v, struct atm_dev, dev_list);
192 
193 		atm_dev_info(seq, dev);
194 	}
195 	return 0;
196 }
197 
198 static const struct seq_operations atm_dev_seq_ops = {
199 	.start	= atm_dev_seq_start,
200 	.next	= atm_dev_seq_next,
201 	.stop	= atm_dev_seq_stop,
202 	.show	= atm_dev_seq_show,
203 };
204 
205 static int pvc_seq_show(struct seq_file *seq, void *v)
206 {
207 	static char atm_pvc_banner[] =
208 		"Itf VPI VCI   AAL RX(PCR,Class) TX(PCR,Class)\n";
209 
210 	if (v == SEQ_START_TOKEN)
211 		seq_puts(seq, atm_pvc_banner);
212 	else {
213 		struct vcc_state *state = seq->private;
214 		struct atm_vcc *vcc = atm_sk(state->sk);
215 
216 		pvc_info(seq, vcc);
217 	}
218 	return 0;
219 }
220 
221 static const struct seq_operations pvc_seq_ops = {
222 	.start	= vcc_seq_start,
223 	.next	= vcc_seq_next,
224 	.stop	= vcc_seq_stop,
225 	.show	= pvc_seq_show,
226 };
227 
228 static int vcc_seq_show(struct seq_file *seq, void *v)
229 {
230 	if (v == SEQ_START_TOKEN) {
231 		seq_printf(seq, sizeof(void *) == 4 ? "%-8s%s" : "%-16s%s",
232 			"Address ", "Itf VPI VCI   Fam Flags Reply "
233 			"Send buffer     Recv buffer      [refcnt]\n");
234 	} else {
235 		struct vcc_state *state = seq->private;
236 		struct atm_vcc *vcc = atm_sk(state->sk);
237 
238 		vcc_info(seq, vcc);
239 	}
240 	return 0;
241 }
242 
243 static const struct seq_operations vcc_seq_ops = {
244 	.start	= vcc_seq_start,
245 	.next	= vcc_seq_next,
246 	.stop	= vcc_seq_stop,
247 	.show	= vcc_seq_show,
248 };
249 
250 static ssize_t proc_dev_atm_read(struct file *file, char __user *buf,
251 				 size_t count, loff_t *pos)
252 {
253 	struct atm_dev *dev;
254 	unsigned long page;
255 	int length;
256 
257 	if (count == 0)
258 		return 0;
259 	page = get_zeroed_page(GFP_KERNEL);
260 	if (!page)
261 		return -ENOMEM;
262 	dev = pde_data(file_inode(file));
263 	if (!dev->ops->proc_read)
264 		length = -EINVAL;
265 	else {
266 		length = dev->ops->proc_read(dev, pos, (char *)page);
267 		if (length > count)
268 			length = -EINVAL;
269 	}
270 	if (length >= 0) {
271 		if (copy_to_user(buf, (char *)page, length))
272 			length = -EFAULT;
273 		(*pos)++;
274 	}
275 	free_page(page);
276 	return length;
277 }
278 
279 struct proc_dir_entry *atm_proc_root;
280 EXPORT_SYMBOL(atm_proc_root);
281 
282 
283 int atm_proc_dev_register(struct atm_dev *dev)
284 {
285 	int error;
286 
287 	/* No proc info */
288 	if (!dev->ops->proc_read)
289 		return 0;
290 
291 	error = -ENOMEM;
292 	dev->proc_name = kasprintf(GFP_KERNEL, "%s:%d", dev->type, dev->number);
293 	if (!dev->proc_name)
294 		goto err_out;
295 
296 	dev->proc_entry = proc_create_data(dev->proc_name, 0, atm_proc_root,
297 					   &atm_dev_proc_ops, dev);
298 	if (!dev->proc_entry)
299 		goto err_free_name;
300 	return 0;
301 
302 err_free_name:
303 	kfree(dev->proc_name);
304 err_out:
305 	return error;
306 }
307 
308 void atm_proc_dev_deregister(struct atm_dev *dev)
309 {
310 	if (!dev->ops->proc_read)
311 		return;
312 
313 	remove_proc_entry(dev->proc_name, atm_proc_root);
314 	kfree(dev->proc_name);
315 }
316 
317 int __init atm_proc_init(void)
318 {
319 	atm_proc_root = proc_net_mkdir(&init_net, "atm", init_net.proc_net);
320 	if (!atm_proc_root)
321 		return -ENOMEM;
322 	proc_create_seq("devices", 0444, atm_proc_root, &atm_dev_seq_ops);
323 	proc_create_seq_private("pvc", 0444, atm_proc_root, &pvc_seq_ops,
324 			sizeof(struct vcc_state), (void *)(uintptr_t)PF_ATMPVC);
325 	proc_create_seq_private("vc", 0444, atm_proc_root, &vcc_seq_ops,
326 			sizeof(struct vcc_state), NULL);
327 	return 0;
328 }
329 
330 void atm_proc_exit(void)
331 {
332 	remove_proc_subtree("atm", init_net.proc_net);
333 }
334