1/*
2 * linux/drivers/scsi/scsi_proc.c
3 *
4 * The functions in this file provide an interface between
5 * the PROC file system and the SCSI device drivers
6 * It is mainly used for debugging, statistics and to pass
7 * information directly to the lowlevel driver.
8 *
9 * (c) 1995 Michael Neuffer neuffer@goofy.zdv.uni-mainz.de
10 * Version: 0.99.8   last change: 95/09/13
11 *
12 * generic command parser provided by:
13 * Andreas Heilwagen <crashcar@informatik.uni-koblenz.de>
14 *
15 * generic_proc_info() support of xxxx_info() by:
16 * Michael A. Griffith <grif@acm.org>
17 */
18
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/string.h>
22#include <linux/mm.h>
23#include <linux/proc_fs.h>
24#include <linux/errno.h>
25#include <linux/blkdev.h>
26#include <linux/seq_file.h>
27#include <linux/mutex.h>
28#include <linux/gfp.h>
29#include <asm/uaccess.h>
30
31#include <scsi/scsi.h>
32#include <scsi/scsi_device.h>
33#include <scsi/scsi_host.h>
34#include <scsi/scsi_transport.h>
35
36#include "scsi_priv.h"
37#include "scsi_logging.h"
38
39
40/* 4K page size, but our output routines, use some slack for overruns */
41#define PROC_BLOCK_SIZE (3*1024)
42
43static struct proc_dir_entry *proc_scsi;
44
45/* Protect sht->present and sht->proc_dir */
46static DEFINE_MUTEX(global_host_template_mutex);
47
48static ssize_t proc_scsi_host_write(struct file *file, const char __user *buf,
49                           size_t count, loff_t *ppos)
50{
51	struct Scsi_Host *shost = PDE_DATA(file_inode(file));
52	ssize_t ret = -ENOMEM;
53	char *page;
54
55	if (count > PROC_BLOCK_SIZE)
56		return -EOVERFLOW;
57
58	if (!shost->hostt->write_info)
59		return -EINVAL;
60
61	page = (char *)__get_free_page(GFP_KERNEL);
62	if (page) {
63		ret = -EFAULT;
64		if (copy_from_user(page, buf, count))
65			goto out;
66		ret = shost->hostt->write_info(shost, page, count);
67	}
68out:
69	free_page((unsigned long)page);
70	return ret;
71}
72
73static int proc_scsi_show(struct seq_file *m, void *v)
74{
75	struct Scsi_Host *shost = m->private;
76	return shost->hostt->show_info(m, shost);
77}
78
79static int proc_scsi_host_open(struct inode *inode, struct file *file)
80{
81	return single_open_size(file, proc_scsi_show, PDE_DATA(inode),
82				4 * PAGE_SIZE);
83}
84
85static const struct file_operations proc_scsi_fops = {
86	.open = proc_scsi_host_open,
87	.release = single_release,
88	.read = seq_read,
89	.llseek = seq_lseek,
90	.write = proc_scsi_host_write
91};
92
93/**
94 * scsi_proc_hostdir_add - Create directory in /proc for a scsi host
95 * @sht: owner of this directory
96 *
97 * Sets sht->proc_dir to the new directory.
98 */
99
100void scsi_proc_hostdir_add(struct scsi_host_template *sht)
101{
102	if (!sht->show_info)
103		return;
104
105	mutex_lock(&global_host_template_mutex);
106	if (!sht->present++) {
107		sht->proc_dir = proc_mkdir(sht->proc_name, proc_scsi);
108        	if (!sht->proc_dir)
109			printk(KERN_ERR "%s: proc_mkdir failed for %s\n",
110			       __func__, sht->proc_name);
111	}
112	mutex_unlock(&global_host_template_mutex);
113}
114
115/**
116 * scsi_proc_hostdir_rm - remove directory in /proc for a scsi host
117 * @sht: owner of directory
118 */
119void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
120{
121	if (!sht->show_info)
122		return;
123
124	mutex_lock(&global_host_template_mutex);
125	if (!--sht->present && sht->proc_dir) {
126		remove_proc_entry(sht->proc_name, proc_scsi);
127		sht->proc_dir = NULL;
128	}
129	mutex_unlock(&global_host_template_mutex);
130}
131
132
133/**
134 * scsi_proc_host_add - Add entry for this host to appropriate /proc dir
135 * @shost: host to add
136 */
137void scsi_proc_host_add(struct Scsi_Host *shost)
138{
139	struct scsi_host_template *sht = shost->hostt;
140	struct proc_dir_entry *p;
141	char name[10];
142
143	if (!sht->proc_dir)
144		return;
145
146	sprintf(name,"%d", shost->host_no);
147	p = proc_create_data(name, S_IRUGO | S_IWUSR,
148		sht->proc_dir, &proc_scsi_fops, shost);
149	if (!p)
150		printk(KERN_ERR "%s: Failed to register host %d in"
151		       "%s\n", __func__, shost->host_no,
152		       sht->proc_name);
153}
154
155/**
156 * scsi_proc_host_rm - remove this host's entry from /proc
157 * @shost: which host
158 */
159void scsi_proc_host_rm(struct Scsi_Host *shost)
160{
161	char name[10];
162
163	if (!shost->hostt->proc_dir)
164		return;
165
166	sprintf(name,"%d", shost->host_no);
167	remove_proc_entry(name, shost->hostt->proc_dir);
168}
169/**
170 * proc_print_scsidevice - return data about this host
171 * @dev: A scsi device
172 * @data: &struct seq_file to output to.
173 *
174 * Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,
175 * and revision.
176 */
177static int proc_print_scsidevice(struct device *dev, void *data)
178{
179	struct scsi_device *sdev;
180	struct seq_file *s = data;
181	int i;
182
183	if (!scsi_is_sdev_device(dev))
184		goto out;
185
186	sdev = to_scsi_device(dev);
187	seq_printf(s,
188		"Host: scsi%d Channel: %02d Id: %02d Lun: %02llu\n  Vendor: ",
189		sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
190	for (i = 0; i < 8; i++) {
191		if (sdev->vendor[i] >= 0x20)
192			seq_putc(s, sdev->vendor[i]);
193		else
194			seq_putc(s, ' ');
195	}
196
197	seq_puts(s, " Model: ");
198	for (i = 0; i < 16; i++) {
199		if (sdev->model[i] >= 0x20)
200			seq_putc(s, sdev->model[i]);
201		else
202			seq_putc(s, ' ');
203	}
204
205	seq_puts(s, " Rev: ");
206	for (i = 0; i < 4; i++) {
207		if (sdev->rev[i] >= 0x20)
208			seq_putc(s, sdev->rev[i]);
209		else
210			seq_putc(s, ' ');
211	}
212
213	seq_putc(s, '\n');
214
215	seq_printf(s, "  Type:   %s ", scsi_device_type(sdev->type));
216	seq_printf(s, "               ANSI  SCSI revision: %02x",
217			sdev->scsi_level - (sdev->scsi_level > 1));
218	if (sdev->scsi_level == 2)
219		seq_puts(s, " CCS\n");
220	else
221		seq_putc(s, '\n');
222
223out:
224	return 0;
225}
226
227/**
228 * scsi_add_single_device - Respond to user request to probe for/add device
229 * @host: user-supplied decimal integer
230 * @channel: user-supplied decimal integer
231 * @id: user-supplied decimal integer
232 * @lun: user-supplied decimal integer
233 *
234 * Description: called by writing "scsi add-single-device" to /proc/scsi/scsi.
235 *
236 * does scsi_host_lookup() and either user_scan() if that transport
237 * type supports it, or else scsi_scan_host_selected()
238 *
239 * Note: this seems to be aimed exclusively at SCSI parallel busses.
240 */
241
242static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
243{
244	struct Scsi_Host *shost;
245	int error = -ENXIO;
246
247	shost = scsi_host_lookup(host);
248	if (!shost)
249		return error;
250
251	if (shost->transportt->user_scan)
252		error = shost->transportt->user_scan(shost, channel, id, lun);
253	else
254		error = scsi_scan_host_selected(shost, channel, id, lun, 1);
255	scsi_host_put(shost);
256	return error;
257}
258
259/**
260 * scsi_remove_single_device - Respond to user request to remove a device
261 * @host: user-supplied decimal integer
262 * @channel: user-supplied decimal integer
263 * @id: user-supplied decimal integer
264 * @lun: user-supplied decimal integer
265 *
266 * Description: called by writing "scsi remove-single-device" to
267 * /proc/scsi/scsi.  Does a scsi_device_lookup() and scsi_remove_device()
268 */
269static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
270{
271	struct scsi_device *sdev;
272	struct Scsi_Host *shost;
273	int error = -ENXIO;
274
275	shost = scsi_host_lookup(host);
276	if (!shost)
277		return error;
278	sdev = scsi_device_lookup(shost, channel, id, lun);
279	if (sdev) {
280		scsi_remove_device(sdev);
281		scsi_device_put(sdev);
282		error = 0;
283	}
284
285	scsi_host_put(shost);
286	return error;
287}
288
289/**
290 * proc_scsi_write - handle writes to /proc/scsi/scsi
291 * @file: not used
292 * @buf: buffer to write
293 * @length: length of buf, at most PAGE_SIZE
294 * @ppos: not used
295 *
296 * Description: this provides a legacy mechanism to add or remove devices by
297 * Host, Channel, ID, and Lun.  To use,
298 * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
299 * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
300 * "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
301 *
302 * Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
303 * SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
304 * provide a unique identifier and nothing more.
305 */
306
307
308static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
309			       size_t length, loff_t *ppos)
310{
311	int host, channel, id, lun;
312	char *buffer, *p;
313	int err;
314
315	if (!buf || length > PAGE_SIZE)
316		return -EINVAL;
317
318	buffer = (char *)__get_free_page(GFP_KERNEL);
319	if (!buffer)
320		return -ENOMEM;
321
322	err = -EFAULT;
323	if (copy_from_user(buffer, buf, length))
324		goto out;
325
326	err = -EINVAL;
327	if (length < PAGE_SIZE)
328		buffer[length] = '\0';
329	else if (buffer[PAGE_SIZE-1])
330		goto out;
331
332	/*
333	 * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
334	 * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
335	 */
336	if (!strncmp("scsi add-single-device", buffer, 22)) {
337		p = buffer + 23;
338
339		host = simple_strtoul(p, &p, 0);
340		channel = simple_strtoul(p + 1, &p, 0);
341		id = simple_strtoul(p + 1, &p, 0);
342		lun = simple_strtoul(p + 1, &p, 0);
343
344		err = scsi_add_single_device(host, channel, id, lun);
345
346	/*
347	 * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
348	 * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
349	 */
350	} else if (!strncmp("scsi remove-single-device", buffer, 25)) {
351		p = buffer + 26;
352
353		host = simple_strtoul(p, &p, 0);
354		channel = simple_strtoul(p + 1, &p, 0);
355		id = simple_strtoul(p + 1, &p, 0);
356		lun = simple_strtoul(p + 1, &p, 0);
357
358		err = scsi_remove_single_device(host, channel, id, lun);
359	}
360
361	/*
362	 * convert success returns so that we return the
363	 * number of bytes consumed.
364	 */
365	if (!err)
366		err = length;
367
368 out:
369	free_page((unsigned long)buffer);
370	return err;
371}
372
373static int always_match(struct device *dev, void *data)
374{
375	return 1;
376}
377
378static inline struct device *next_scsi_device(struct device *start)
379{
380	struct device *next = bus_find_device(&scsi_bus_type, start, NULL,
381					      always_match);
382	put_device(start);
383	return next;
384}
385
386static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos)
387{
388	struct device *dev = NULL;
389	loff_t n = *pos;
390
391	while ((dev = next_scsi_device(dev))) {
392		if (!n--)
393			break;
394		sfile->private++;
395	}
396	return dev;
397}
398
399static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos)
400{
401	(*pos)++;
402	sfile->private++;
403	return next_scsi_device(v);
404}
405
406static void scsi_seq_stop(struct seq_file *sfile, void *v)
407{
408	put_device(v);
409}
410
411static int scsi_seq_show(struct seq_file *sfile, void *dev)
412{
413	if (!sfile->private)
414		seq_puts(sfile, "Attached devices:\n");
415
416	return proc_print_scsidevice(dev, sfile);
417}
418
419static const struct seq_operations scsi_seq_ops = {
420	.start	= scsi_seq_start,
421	.next	= scsi_seq_next,
422	.stop	= scsi_seq_stop,
423	.show	= scsi_seq_show
424};
425
426/**
427 * proc_scsi_open - glue function
428 * @inode: not used
429 * @file: passed to single_open()
430 *
431 * Associates proc_scsi_show with this file
432 */
433static int proc_scsi_open(struct inode *inode, struct file *file)
434{
435	/*
436	 * We don't really need this for the write case but it doesn't
437	 * harm either.
438	 */
439	return seq_open(file, &scsi_seq_ops);
440}
441
442static const struct file_operations proc_scsi_operations = {
443	.owner		= THIS_MODULE,
444	.open		= proc_scsi_open,
445	.read		= seq_read,
446	.write		= proc_scsi_write,
447	.llseek		= seq_lseek,
448	.release	= seq_release,
449};
450
451/**
452 * scsi_init_procfs - create scsi and scsi/scsi in procfs
453 */
454int __init scsi_init_procfs(void)
455{
456	struct proc_dir_entry *pde;
457
458	proc_scsi = proc_mkdir("scsi", NULL);
459	if (!proc_scsi)
460		goto err1;
461
462	pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
463	if (!pde)
464		goto err2;
465
466	return 0;
467
468err2:
469	remove_proc_entry("scsi", NULL);
470err1:
471	return -ENOMEM;
472}
473
474/**
475 * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
476 */
477void scsi_exit_procfs(void)
478{
479	remove_proc_entry("scsi/scsi", NULL);
480	remove_proc_entry("scsi", NULL);
481}
482