[linux-2.6-block.git] / drivers / scsi / scsi_proc.c

// SPDX-License-Identifier: GPL-2.0
/*
 * linux/drivers/scsi/scsi_proc.c
 *
 * The functions in this file provide an interface between
 * the PROC file system and the SCSI device drivers
 * It is mainly used for debugging, statistics and to pass 
 * information directly to the lowlevel driver.
 *
 * (c) 1995 Michael Neuffer neuffer@goofy.zdv.uni-mainz.de 
 * Version: 0.99.8   last change: 95/09/13
 * 
 * generic command parser provided by: 
 * Andreas Heilwagen <crashcar@informatik.uni-koblenz.de>
 *
 * generic_proc_info() support of xxxx_info() by:
 * Michael A. Griffith <grif@acm.org>
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/proc_fs.h>
#include <linux/errno.h>
#include <linux/blkdev.h>
#include <linux/seq_file.h>
#include <linux/mutex.h>
#include <linux/gfp.h>
#include <linux/uaccess.h>

#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>

#include "scsi_priv.h"
#include "scsi_logging.h"


/* 4K page size, but our output routines, use some slack for overruns */
#define PROC_BLOCK_SIZE (3*1024)

static struct proc_dir_entry *proc_scsi;

/* Protect sht->present and sht->proc_dir */
static DEFINE_MUTEX(global_host_template_mutex);

static ssize_t proc_scsi_host_write(struct file *file, const char __user *buf,
                           size_t count, loff_t *ppos)
{
	struct Scsi_Host *shost = PDE_DATA(file_inode(file));
	ssize_t ret = -ENOMEM;
	char *page;
    
	if (count > PROC_BLOCK_SIZE)
		return -EOVERFLOW;

	if (!shost->hostt->write_info)
		return -EINVAL;

	page = (char *)__get_free_page(GFP_KERNEL);
	if (page) {
		ret = -EFAULT;
		if (copy_from_user(page, buf, count))
			goto out;
		ret = shost->hostt->write_info(shost, page, count);
	}
out:
	free_page((unsigned long)page);
	return ret;
}

static int proc_scsi_show(struct seq_file *m, void *v)
{
	struct Scsi_Host *shost = m->private;
	return shost->hostt->show_info(m, shost);
}

static int proc_scsi_host_open(struct inode *inode, struct file *file)
{
	return single_open_size(file, proc_scsi_show, PDE_DATA(inode),
				4 * PAGE_SIZE);
}

static const struct file_operations proc_scsi_fops = {
	.open = proc_scsi_host_open,
	.release = single_release,
	.read = seq_read,
	.llseek = seq_lseek,
	.write = proc_scsi_host_write
};

/**
 * scsi_proc_hostdir_add - Create directory in /proc for a scsi host
 * @sht: owner of this directory
 *
 * Sets sht->proc_dir to the new directory.
 */

void scsi_proc_hostdir_add(struct scsi_host_template *sht)
{
	if (!sht->show_info)
		return;

	mutex_lock(&global_host_template_mutex);
	if (!sht->present++) {
		sht->proc_dir = proc_mkdir(sht->proc_name, proc_scsi);
        	if (!sht->proc_dir)
			printk(KERN_ERR "%s: proc_mkdir failed for %s\n",
			       __func__, sht->proc_name);
	}
	mutex_unlock(&global_host_template_mutex);
}

/**
 * scsi_proc_hostdir_rm - remove directory in /proc for a scsi host
 * @sht: owner of directory
 */
void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
{
	if (!sht->show_info)
		return;

	mutex_lock(&global_host_template_mutex);
	if (!--sht->present && sht->proc_dir) {
		remove_proc_entry(sht->proc_name, proc_scsi);
		sht->proc_dir = NULL;
	}
	mutex_unlock(&global_host_template_mutex);
}


/**
 * scsi_proc_host_add - Add entry for this host to appropriate /proc dir
 * @shost: host to add
 */
void scsi_proc_host_add(struct Scsi_Host *shost)
{
	struct scsi_host_template *sht = shost->hostt;
	struct proc_dir_entry *p;
	char name[10];

	if (!sht->proc_dir)
		return;

	sprintf(name,"%d", shost->host_no);
	p = proc_create_data(name, S_IRUGO | S_IWUSR,
		sht->proc_dir, &proc_scsi_fops, shost);
	if (!p)
		printk(KERN_ERR "%s: Failed to register host %d in"
		       "%s\n", __func__, shost->host_no,
		       sht->proc_name);
}

/**
 * scsi_proc_host_rm - remove this host's entry from /proc
 * @shost: which host
 */
void scsi_proc_host_rm(struct Scsi_Host *shost)
{
	char name[10];

	if (!shost->hostt->proc_dir)
		return;

	sprintf(name,"%d", shost->host_no);
	remove_proc_entry(name, shost->hostt->proc_dir);
}
/**
 * proc_print_scsidevice - return data about this host
 * @dev: A scsi device
 * @data: &struct seq_file to output to.
 *
 * Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,
 * and revision.
 */
static int proc_print_scsidevice(struct device *dev, void *data)
{
	struct scsi_device *sdev;
	struct seq_file *s = data;
	int i;

	if (!scsi_is_sdev_device(dev))
		goto out;

	sdev = to_scsi_device(dev);
	seq_printf(s,
		"Host: scsi%d Channel: %02d Id: %02d Lun: %02llu\n  Vendor: ",
		sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
	for (i = 0; i < 8; i++) {
		if (sdev->vendor[i] >= 0x20)
			seq_putc(s, sdev->vendor[i]);
		else
			seq_putc(s, ' ');
	}

	seq_puts(s, " Model: ");
	for (i = 0; i < 16; i++) {
		if (sdev->model[i] >= 0x20)
			seq_putc(s, sdev->model[i]);
		else
			seq_putc(s, ' ');
	}

	seq_puts(s, " Rev: ");
	for (i = 0; i < 4; i++) {
		if (sdev->rev[i] >= 0x20)
			seq_putc(s, sdev->rev[i]);
		else
			seq_putc(s, ' ');
	}

	seq_putc(s, '\n');

	seq_printf(s, "  Type:   %s ", scsi_device_type(sdev->type));
	seq_printf(s, "               ANSI  SCSI revision: %02x",
			sdev->scsi_level - (sdev->scsi_level > 1));
	if (sdev->scsi_level == 2)
		seq_puts(s, " CCS\n");
	else
		seq_putc(s, '\n');

out:
	return 0;
}

/**
 * scsi_add_single_device - Respond to user request to probe for/add device
 * @host: user-supplied decimal integer
 * @channel: user-supplied decimal integer
 * @id: user-supplied decimal integer
 * @lun: user-supplied decimal integer
 *
 * Description: called by writing "scsi add-single-device" to /proc/scsi/scsi.
 *
 * does scsi_host_lookup() and either user_scan() if that transport
 * type supports it, or else scsi_scan_host_selected()
 *
 * Note: this seems to be aimed exclusively at SCSI parallel busses.
 */

static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
{
	struct Scsi_Host *shost;
	int error = -ENXIO;

	shost = scsi_host_lookup(host);
	if (!shost)
		return error;

	if (shost->transportt->user_scan)
		error = shost->transportt->user_scan(shost, channel, id, lun);
	else
		error = scsi_scan_host_selected(shost, channel, id, lun,
						SCSI_SCAN_MANUAL);
	scsi_host_put(shost);
	return error;
}

/**
 * scsi_remove_single_device - Respond to user request to remove a device
 * @host: user-supplied decimal integer
 * @channel: user-supplied decimal integer
 * @id: user-supplied decimal integer
 * @lun: user-supplied decimal integer
 *
 * Description: called by writing "scsi remove-single-device" to
 * /proc/scsi/scsi.  Does a scsi_device_lookup() and scsi_remove_device()
 */
static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
{
	struct scsi_device *sdev;
	struct Scsi_Host *shost;
	int error = -ENXIO;

	shost = scsi_host_lookup(host);
	if (!shost)
		return error;
	sdev = scsi_device_lookup(shost, channel, id, lun);
	if (sdev) {
		scsi_remove_device(sdev);
		scsi_device_put(sdev);
		error = 0;
	}

	scsi_host_put(shost);
	return error;
}

/**
 * proc_scsi_write - handle writes to /proc/scsi/scsi
 * @file: not used
 * @buf: buffer to write
 * @length: length of buf, at most PAGE_SIZE
 * @ppos: not used
 *
 * Description: this provides a legacy mechanism to add or remove devices by
 * Host, Channel, ID, and Lun.  To use,
 * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
 * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
 * "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
 *
 * Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
 * SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
 * provide a unique identifier and nothing more.
 */


static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
			       size_t length, loff_t *ppos)
{
	int host, channel, id, lun;
	char *buffer, *p;
	int err;

	if (!buf || length > PAGE_SIZE)
		return -EINVAL;

	buffer = (char *)__get_free_page(GFP_KERNEL);
	if (!buffer)
		return -ENOMEM;

	err = -EFAULT;
	if (copy_from_user(buffer, buf, length))
		goto out;

	err = -EINVAL;
	if (length < PAGE_SIZE)
		buffer[length] = '\0';
	else if (buffer[PAGE_SIZE-1])
		goto out;

	/*
	 * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
	 * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
	 */
	if (!strncmp("scsi add-single-device", buffer, 22)) {
		p = buffer + 23;

		host = simple_strtoul(p, &p, 0);
		channel = simple_strtoul(p + 1, &p, 0);
		id = simple_strtoul(p + 1, &p, 0);
		lun = simple_strtoul(p + 1, &p, 0);

		err = scsi_add_single_device(host, channel, id, lun);

	/*
	 * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
	 * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
	 */
	} else if (!strncmp("scsi remove-single-device", buffer, 25)) {
		p = buffer + 26;

		host = simple_strtoul(p, &p, 0);
		channel = simple_strtoul(p + 1, &p, 0);
		id = simple_strtoul(p + 1, &p, 0);
		lun = simple_strtoul(p + 1, &p, 0);

		err = scsi_remove_single_device(host, channel, id, lun);
	}

	/*
	 * convert success returns so that we return the 
	 * number of bytes consumed.
	 */
	if (!err)
		err = length;

 out:
	free_page((unsigned long)buffer);
	return err;
}

static int always_match(struct device *dev, const void *data)
{
	return 1;
}

static inline struct device *next_scsi_device(struct device *start)
{
	struct device *next = bus_find_device(&scsi_bus_type, start, NULL,
					      always_match);
	put_device(start);
	return next;
}

static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos)
{
	struct device *dev = NULL;
	loff_t n = *pos;

	while ((dev = next_scsi_device(dev))) {
		if (!n--)
			break;
		sfile->private++;
	}
	return dev;
}

static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos)
{
	(*pos)++;
	sfile->private++;
	return next_scsi_device(v);
}

static void scsi_seq_stop(struct seq_file *sfile, void *v)
{
	put_device(v);
}

static int scsi_seq_show(struct seq_file *sfile, void *dev)
{
	if (!sfile->private)
		seq_puts(sfile, "Attached devices:\n");

	return proc_print_scsidevice(dev, sfile);
}

static const struct seq_operations scsi_seq_ops = {
	.start	= scsi_seq_start,
	.next	= scsi_seq_next,
	.stop	= scsi_seq_stop,
	.show	= scsi_seq_show
};

/**
 * proc_scsi_open - glue function
 * @inode: not used
 * @file: passed to single_open()
 *
 * Associates proc_scsi_show with this file
 */
static int proc_scsi_open(struct inode *inode, struct file *file)
{
	/*
	 * We don't really need this for the write case but it doesn't
	 * harm either.
	 */
	return seq_open(file, &scsi_seq_ops);
}

static const struct file_operations proc_scsi_operations = {
	.owner		= THIS_MODULE,
	.open		= proc_scsi_open,
	.read		= seq_read,
	.write		= proc_scsi_write,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

/**
 * scsi_init_procfs - create scsi and scsi/scsi in procfs
 */
int __init scsi_init_procfs(void)
{
	struct proc_dir_entry *pde;

	proc_scsi = proc_mkdir("scsi", NULL);
	if (!proc_scsi)
		goto err1;

	pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
	if (!pde)
		goto err2;

	return 0;

err2:
	remove_proc_entry("scsi", NULL);
err1:
	return -ENOMEM;
}

/**
 * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
 */
void scsi_exit_procfs(void)
{
	remove_proc_entry("scsi/scsi", NULL);
	remove_proc_entry("scsi", NULL);
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/drivers/scsi/scsi_proc.c
	4	*
	5	* The functions in this file provide an interface between
	6	* the PROC file system and the SCSI device drivers
	7	* It is mainly used for debugging, statistics and to pass
	8	* information directly to the lowlevel driver.
	9	*
	10	* (c) 1995 Michael Neuffer neuffer@goofy.zdv.uni-mainz.de
	11	* Version: 0.99.8 last change: 95/09/13
	12	*
	13	* generic command parser provided by:
	14	* Andreas Heilwagen <crashcar@informatik.uni-koblenz.de>
	15	*
	16	* generic_proc_info() support of xxxx_info() by:
	17	* Michael A. Griffith <grif@acm.org>
	18	*/
	19
	20	#include <linux/module.h>
	21	#include <linux/init.h>
	22	#include <linux/string.h>
	23	#include <linux/mm.h>
1da177e4 LT	24	#include <linux/proc_fs.h>
	25	#include <linux/errno.h>
	26	#include <linux/blkdev.h>
	27	#include <linux/seq_file.h>
0b950672	28	#include <linux/mutex.h>
5a0e3ad6	29	#include <linux/gfp.h>
7c0f6ba6	30	#include <linux/uaccess.h>
1da177e4 LT	31
	32	#include <scsi/scsi.h>
	33	#include <scsi/scsi_device.h>
	34	#include <scsi/scsi_host.h>
e02f3f59	35	#include <scsi/scsi_transport.h>
1da177e4 LT	36
	37	#include "scsi_priv.h"
	38	#include "scsi_logging.h"
	39
	40
	41	/* 4K page size, but our output routines, use some slack for overruns */
	42	#define PROC_BLOCK_SIZE (3*1024)
	43
	44	static struct proc_dir_entry *proc_scsi;
	45
	46	/* Protect sht->present and sht->proc_dir */
0b950672	47	static DEFINE_MUTEX(global_host_template_mutex);
1da177e4	48
0ffddfbb AV	49	static ssize_t proc_scsi_host_write(struct file file, const char __user buf,
	50	size_t count, loff_t *ppos)
	51	{
d9dda78b	52	struct Scsi_Host *shost = PDE_DATA(file_inode(file));
0ffddfbb AV	53	ssize_t ret = -ENOMEM;
	54	char *page;
	55
	56	if (count > PROC_BLOCK_SIZE)
	57	return -EOVERFLOW;
	58
	59	if (!shost->hostt->write_info)
	60	return -EINVAL;
	61
	62	page = (char *)__get_free_page(GFP_KERNEL);
	63	if (page) {
	64	ret = -EFAULT;
	65	if (copy_from_user(page, buf, count))
	66	goto out;
	67	ret = shost->hostt->write_info(shost, page, count);
	68	}
	69	out:
	70	free_page((unsigned long)page);
	71	return ret;
	72	}
	73
	74	static int proc_scsi_show(struct seq_file m, void v)
	75	{
	76	struct Scsi_Host *shost = m->private;
	77	return shost->hostt->show_info(m, shost);
	78	}
	79
	80	static int proc_scsi_host_open(struct inode inode, struct file file)
	81	{
d9dda78b	82	return single_open_size(file, proc_scsi_show, PDE_DATA(inode),
859d22f9	83	4 * PAGE_SIZE);
0ffddfbb AV	84	}
	85
	86	static const struct file_operations proc_scsi_fops = {
	87	.open = proc_scsi_host_open,
801d9d26	88	.release = single_release,
0ffddfbb AV	89	.read = seq_read,
	90	.llseek = seq_lseek,
	91	.write = proc_scsi_host_write
	92	};
	93
eb44820c RL	94	/**
	95	* scsi_proc_hostdir_add - Create directory in /proc for a scsi host
	96	* @sht: owner of this directory
	97	*
	98	* Sets sht->proc_dir to the new directory.
	99	*/
	100
1da177e4 LT	101	void scsi_proc_hostdir_add(struct scsi_host_template *sht)
1da177e4 LT	102	{
70ef457d	103	if (!sht->show_info)
1da177e4 LT	104	return;
1da177e4 LT	105
0b950672	106	mutex_lock(&global_host_template_mutex);
1da177e4 LT	107	if (!sht->present++) {
	108	sht->proc_dir = proc_mkdir(sht->proc_name, proc_scsi);
	109	if (!sht->proc_dir)
	110	printk(KERN_ERR "%s: proc_mkdir failed for %s\n",
cadbd4a5	111	__func__, sht->proc_name);
1da177e4	112	}
0b950672	113	mutex_unlock(&global_host_template_mutex);
1da177e4 LT	114	}
1da177e4 LT	115
eb44820c RL	116	/**
	117	* scsi_proc_hostdir_rm - remove directory in /proc for a scsi host
	118	* @sht: owner of directory
	119	*/
1da177e4 LT	120	void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
1da177e4 LT	121	{
70ef457d	122	if (!sht->show_info)
1da177e4 LT	123	return;
1da177e4 LT	124
0b950672	125	mutex_lock(&global_host_template_mutex);
1da177e4 LT	126	if (!--sht->present && sht->proc_dir) {
	127	remove_proc_entry(sht->proc_name, proc_scsi);
	128	sht->proc_dir = NULL;
	129	}
0b950672	130	mutex_unlock(&global_host_template_mutex);
1da177e4 LT	131	}
1da177e4 LT	132
eb44820c RL	133
	134	/**
	135	* scsi_proc_host_add - Add entry for this host to appropriate /proc dir
	136	* @shost: host to add
	137	*/
1da177e4 LT	138	void scsi_proc_host_add(struct Scsi_Host *shost)
	139	{
	140	struct scsi_host_template *sht = shost->hostt;
	141	struct proc_dir_entry *p;
	142	char name[10];
	143
	144	if (!sht->proc_dir)
	145	return;
	146
	147	sprintf(name,"%d", shost->host_no);
70ef457d AV	148	p = proc_create_data(name, S_IRUGO \| S_IWUSR,
	149	sht->proc_dir, &proc_scsi_fops, shost);
	150	if (!p)
	151	printk(KERN_ERR "%s: Failed to register host %d in"
	152	"%s\n", __func__, shost->host_no,
	153	sht->proc_name);
1da177e4 LT	154	}
1da177e4 LT	155
eb44820c RL	156	/**
	157	* scsi_proc_host_rm - remove this host's entry from /proc
	158	* @shost: which host
	159	*/
1da177e4 LT	160	void scsi_proc_host_rm(struct Scsi_Host *shost)
	161	{
	162	char name[10];
	163
	164	if (!shost->hostt->proc_dir)
	165	return;
	166
	167	sprintf(name,"%d", shost->host_no);
	168	remove_proc_entry(name, shost->hostt->proc_dir);
	169	}
eb44820c RL	170	/**
	171	* proc_print_scsidevice - return data about this host
	172	* @dev: A scsi device
	173	* @data: &struct seq_file to output to.
	174	*
	175	* Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,
	176	* and revision.
	177	*/
1da177e4 LT	178	static int proc_print_scsidevice(struct device dev, void data)
1da177e4 LT	179	{
b0ed4336	180	struct scsi_device *sdev;
1da177e4 LT	181	struct seq_file *s = data;
	182	int i;
	183
b0ed4336 HR	184	if (!scsi_is_sdev_device(dev))
	185	goto out;
	186
	187	sdev = to_scsi_device(dev);
1da177e4	188	seq_printf(s,
9cb78c16	189	"Host: scsi%d Channel: %02d Id: %02d Lun: %02llu\n Vendor: ",
1da177e4 LT	190	sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
	191	for (i = 0; i < 8; i++) {
	192	if (sdev->vendor[i] >= 0x20)
91c40f24	193	seq_putc(s, sdev->vendor[i]);
1da177e4	194	else
f50332ff	195	seq_putc(s, ' ');
1da177e4 LT	196	}
1da177e4 LT	197
91c40f24	198	seq_puts(s, " Model: ");
1da177e4 LT	199	for (i = 0; i < 16; i++) {
1da177e4 LT	200	if (sdev->model[i] >= 0x20)
91c40f24	201	seq_putc(s, sdev->model[i]);
1da177e4	202	else
f50332ff	203	seq_putc(s, ' ');
1da177e4 LT	204	}
1da177e4 LT	205
91c40f24	206	seq_puts(s, " Rev: ");
1da177e4 LT	207	for (i = 0; i < 4; i++) {
1da177e4 LT	208	if (sdev->rev[i] >= 0x20)
91c40f24	209	seq_putc(s, sdev->rev[i]);
1da177e4	210	else
f50332ff	211	seq_putc(s, ' ');
1da177e4 LT	212	}
1da177e4 LT	213
f50332ff	214	seq_putc(s, '\n');
1da177e4	215
4ff36718	216	seq_printf(s, " Type: %s ", scsi_device_type(sdev->type));
74feb53e AS	217	seq_printf(s, " ANSI SCSI revision: %02x",
74feb53e AS	218	sdev->scsi_level - (sdev->scsi_level > 1));
1da177e4	219	if (sdev->scsi_level == 2)
91c40f24	220	seq_puts(s, " CCS\n");
1da177e4	221	else
f50332ff	222	seq_putc(s, '\n');
1da177e4	223
b0ed4336	224	out:
1da177e4 LT	225	return 0;
	226	}
	227
eb44820c RL	228	/**
	229	* scsi_add_single_device - Respond to user request to probe for/add device
	230	* @host: user-supplied decimal integer
	231	* @channel: user-supplied decimal integer
	232	* @id: user-supplied decimal integer
	233	* @lun: user-supplied decimal integer
	234	*
	235	* Description: called by writing "scsi add-single-device" to /proc/scsi/scsi.
	236	*
	237	* does scsi_host_lookup() and either user_scan() if that transport
	238	* type supports it, or else scsi_scan_host_selected()
	239	*
	240	* Note: this seems to be aimed exclusively at SCSI parallel busses.
	241	*/
	242
1da177e4 LT	243	static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
	244	{
	245	struct Scsi_Host *shost;
	246	int error = -ENXIO;
	247
	248	shost = scsi_host_lookup(host);
315cb0ad JS	249	if (!shost)
315cb0ad JS	250	return error;
1da177e4	251
e02f3f59 CH	252	if (shost->transportt->user_scan)
	253	error = shost->transportt->user_scan(shost, channel, id, lun);
	254	else
1d645088 HR	255	error = scsi_scan_host_selected(shost, channel, id, lun,
1d645088 HR	256	SCSI_SCAN_MANUAL);
1da177e4 LT	257	scsi_host_put(shost);
	258	return error;
	259	}
	260
eb44820c RL	261	/**
	262	* scsi_remove_single_device - Respond to user request to remove a device
	263	* @host: user-supplied decimal integer
	264	* @channel: user-supplied decimal integer
	265	* @id: user-supplied decimal integer
	266	* @lun: user-supplied decimal integer
	267	*
	268	* Description: called by writing "scsi remove-single-device" to
	269	* /proc/scsi/scsi. Does a scsi_device_lookup() and scsi_remove_device()
	270	*/
1da177e4 LT	271	static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
	272	{
	273	struct scsi_device *sdev;
	274	struct Scsi_Host *shost;
	275	int error = -ENXIO;
	276
	277	shost = scsi_host_lookup(host);
315cb0ad JS	278	if (!shost)
315cb0ad JS	279	return error;
1da177e4 LT	280	sdev = scsi_device_lookup(shost, channel, id, lun);
	281	if (sdev) {
	282	scsi_remove_device(sdev);
	283	scsi_device_put(sdev);
	284	error = 0;
	285	}
	286
	287	scsi_host_put(shost);
	288	return error;
	289	}
	290
eb44820c RL	291	/**
	292	* proc_scsi_write - handle writes to /proc/scsi/scsi
	293	* @file: not used
	294	* @buf: buffer to write
	295	* @length: length of buf, at most PAGE_SIZE
	296	* @ppos: not used
	297	*
	298	* Description: this provides a legacy mechanism to add or remove devices by
	299	* Host, Channel, ID, and Lun. To use,
	300	* "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
	301	* "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
	302	* "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
	303	*
	304	* Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
	305	* SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
	306	* provide a unique identifier and nothing more.
	307	*/
	308
	309
1da177e4 LT	310	static ssize_t proc_scsi_write(struct file file, const char __user buf,
	311	size_t length, loff_t *ppos)
	312	{
	313	int host, channel, id, lun;
	314	char buffer, p;
	315	int err;
	316
	317	if (!buf \|\| length > PAGE_SIZE)
	318	return -EINVAL;
	319
	320	buffer = (char *)__get_free_page(GFP_KERNEL);
	321	if (!buffer)
	322	return -ENOMEM;
	323
	324	err = -EFAULT;
	325	if (copy_from_user(buffer, buf, length))
	326	goto out;
	327
	328	err = -EINVAL;
	329	if (length < PAGE_SIZE)
	330	buffer[length] = '\0';
	331	else if (buffer[PAGE_SIZE-1])
	332	goto out;
	333
	334	/*
	335	* Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
	336	* with "0 1 2 3" replaced by your "Host Channel Id Lun".
	337	*/
	338	if (!strncmp("scsi add-single-device", buffer, 22)) {
	339	p = buffer + 23;
	340
	341	host = simple_strtoul(p, &p, 0);
	342	channel = simple_strtoul(p + 1, &p, 0);
	343	id = simple_strtoul(p + 1, &p, 0);
	344	lun = simple_strtoul(p + 1, &p, 0);
	345
	346	err = scsi_add_single_device(host, channel, id, lun);
1da177e4 LT	347
	348	/*
	349	* Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
	350	* with "0 1 2 3" replaced by your "Host Channel Id Lun".
	351	*/
	352	} else if (!strncmp("scsi remove-single-device", buffer, 25)) {
	353	p = buffer + 26;
	354
	355	host = simple_strtoul(p, &p, 0);
	356	channel = simple_strtoul(p + 1, &p, 0);
	357	id = simple_strtoul(p + 1, &p, 0);
	358	lun = simple_strtoul(p + 1, &p, 0);
	359
	360	err = scsi_remove_single_device(host, channel, id, lun);
	361	}
	362
2ca48a13 JB	363	/*
	364	* convert success returns so that we return the
	365	* number of bytes consumed.
	366	*/
	367	if (!err)
	368	err = length;
	369
1da177e4 LT	370	out:
	371	free_page((unsigned long)buffer);
	372	return err;
	373	}
	374
418e3ea1	375	static int always_match(struct device dev, const void data)
1da177e4	376	{
e37c4913 JM	377	return 1;
	378	}
	379
	380	static inline struct device next_scsi_device(struct device start)
	381	{
	382	struct device *next = bus_find_device(&scsi_bus_type, start, NULL,
	383	always_match);
	384	put_device(start);
	385	return next;
1da177e4 LT	386	}
1da177e4 LT	387
e37c4913 JM	388	static void scsi_seq_start(struct seq_file sfile, loff_t *pos)
	389	{
	390	struct device *dev = NULL;
	391	loff_t n = *pos;
	392
	393	while ((dev = next_scsi_device(dev))) {
	394	if (!n--)
	395	break;
	396	sfile->private++;
	397	}
	398	return dev;
	399	}
	400
	401	static void scsi_seq_next(struct seq_file sfile, void v, loff_t pos)
	402	{
	403	(*pos)++;
	404	sfile->private++;
	405	return next_scsi_device(v);
	406	}
	407
	408	static void scsi_seq_stop(struct seq_file sfile, void v)
	409	{
	410	put_device(v);
	411	}
	412
	413	static int scsi_seq_show(struct seq_file sfile, void dev)
	414	{
	415	if (!sfile->private)
	416	seq_puts(sfile, "Attached devices:\n");
	417
	418	return proc_print_scsidevice(dev, sfile);
	419	}
	420
	421	static const struct seq_operations scsi_seq_ops = {
	422	.start = scsi_seq_start,
	423	.next = scsi_seq_next,
	424	.stop = scsi_seq_stop,
	425	.show = scsi_seq_show
	426	};
	427
eb44820c RL	428	/**
	429	* proc_scsi_open - glue function
	430	* @inode: not used
	431	* @file: passed to single_open()
	432	*
	433	* Associates proc_scsi_show with this file
	434	*/
1da177e4 LT	435	static int proc_scsi_open(struct inode inode, struct file file)
	436	{
	437	/*
eb44820c	438	* We don't really need this for the write case but it doesn't
1da177e4 LT	439	* harm either.
1da177e4 LT	440	*/
e37c4913	441	return seq_open(file, &scsi_seq_ops);
1da177e4 LT	442	}
1da177e4 LT	443
00977a59	444	static const struct file_operations proc_scsi_operations = {
a973909f	445	.owner = THIS_MODULE,
1da177e4 LT	446	.open = proc_scsi_open,
	447	.read = seq_read,
	448	.write = proc_scsi_write,
	449	.llseek = seq_lseek,
e37c4913	450	.release = seq_release,
1da177e4 LT	451	};
1da177e4 LT	452
eb44820c RL	453	/**
	454	* scsi_init_procfs - create scsi and scsi/scsi in procfs
	455	*/
1da177e4 LT	456	int __init scsi_init_procfs(void)
	457	{
	458	struct proc_dir_entry *pde;
	459
	460	proc_scsi = proc_mkdir("scsi", NULL);
	461	if (!proc_scsi)
	462	goto err1;
	463
a973909f	464	pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
1da177e4 LT	465	if (!pde)
1da177e4 LT	466	goto err2;
1da177e4 LT	467
	468	return 0;
	469
	470	err2:
	471	remove_proc_entry("scsi", NULL);
	472	err1:
	473	return -ENOMEM;
	474	}
	475
eb44820c RL	476	/**
	477	* scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
	478	*/
1da177e4 LT	479	void scsi_exit_procfs(void)
	480	{
	481	remove_proc_entry("scsi/scsi", NULL);
	482	remove_proc_entry("scsi", NULL);
	483	}