[mirror_ubuntu-bionic-kernel.git] / drivers / scsi / scsi_proc.c

/*
 * 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 <asm/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(file_inode(file))->data;
	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(file, proc_scsi_show, PDE(inode)->data);
}

static const struct file_operations proc_scsi_fops = {
	.open = proc_scsi_host_open,
	.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: %02d\n  Vendor: ",
		sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
	for (i = 0; i < 8; i++) {
		if (sdev->vendor[i] >= 0x20)
			seq_printf(s, "%c", sdev->vendor[i]);
		else
			seq_printf(s, " ");
	}

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

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

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