[GitHub/mt8127/android_kernel_alcatel_ttab.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);

/**
 * proc_scsi_read - handle read from /proc by calling host's proc_info() command
 * @buffer: passed to proc_info
 * @start: passed to proc_info
 * @offset: passed to proc_info
 * @length: passed to proc_info
 * @eof: returns whether length read was less than requested
 * @data: pointer to a &struct Scsi_Host
 */

static int proc_scsi_read(char *buffer, char **start, off_t offset,
			  int length, int *eof, void *data)
{
	struct Scsi_Host *shost = data;
	int n;

	n = shost->hostt->proc_info(shost, buffer, start, offset, length, 0);
	*eof = (n < length);

	return n;
}

/**
 * proc_scsi_write_proc - Handle write to /proc by calling host's proc_info()
 * @file: not used
 * @buf: source of data to write.
 * @count: number of bytes (at most PROC_BLOCK_SIZE) to write.
 * @data: pointer to &struct Scsi_Host
 */
static int proc_scsi_write_proc(struct file *file, const char __user *buf,
                           unsigned long count, void *data)
{
	struct Scsi_Host *shost = data;
	ssize_t ret = -ENOMEM;
	char *page;
	char *start;
    
	if (count > PROC_BLOCK_SIZE)
		return -EOVERFLOW;

	page = (char *)__get_free_page(GFP_KERNEL);
	if (page) {
		ret = -EFAULT;
		if (copy_from_user(page, buf, count))
			goto out;
		ret = shost->hostt->proc_info(shost, page, &start, 0, count, 1);
	}
out:
	free_page((unsigned long)page);
	return ret;
}

/**
 * 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->proc_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->proc_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 = create_proc_read_entry(name, S_IFREG | S_IRUGO | S_IWUSR,
			sht->proc_dir, proc_scsi_read, shost);
	if (!p) {
		printk(KERN_ERR "%s: Failed to register host %d in"
		       "%s\n", __func__, shost->host_no,
		       sht->proc_name);
		return;
	} 

	p->write_proc = proc_scsi_write_proc;
}

/**
 * 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;
}

/**
 * proc_scsi_show - show contents of /proc/scsi/scsi (attached devices)
 * @s: output goes here
 * @p: not used
 */
static int proc_scsi_show(struct seq_file *s, void *p)
{
	seq_printf(s, "Attached devices:\n");
	bus_for_each_dev(&scsi_bus_type, NULL, s, proc_print_scsidevice);
	return 0;
}

/**
 * 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 single_open(file, proc_scsi_show, NULL);
}

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	= single_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
eb44820c RL	48	/**
	49	* proc_scsi_read - handle read from /proc by calling host's proc_info() command
	50	* @buffer: passed to proc_info
	51	* @start: passed to proc_info
	52	* @offset: passed to proc_info
	53	* @length: passed to proc_info
	54	* @eof: returns whether length read was less than requested
	55	* @data: pointer to a &struct Scsi_Host
	56	*/
	57
1da177e4 LT	58	static int proc_scsi_read(char buffer, char *start, off_t offset,
	59	int length, int eof, void data)
	60	{
	61	struct Scsi_Host *shost = data;
	62	int n;
	63
	64	n = shost->hostt->proc_info(shost, buffer, start, offset, length, 0);
	65	*eof = (n < length);
	66
	67	return n;
	68	}
	69
eb44820c RL	70	/**
	71	* proc_scsi_write_proc - Handle write to /proc by calling host's proc_info()
	72	* @file: not used
	73	* @buf: source of data to write.
	74	* @count: number of bytes (at most PROC_BLOCK_SIZE) to write.
	75	* @data: pointer to &struct Scsi_Host
	76	*/
1da177e4 LT	77	static int proc_scsi_write_proc(struct file file, const char __user buf,
	78	unsigned long count, void *data)
	79	{
	80	struct Scsi_Host *shost = data;
	81	ssize_t ret = -ENOMEM;
	82	char *page;
	83	char *start;
	84
	85	if (count > PROC_BLOCK_SIZE)
	86	return -EOVERFLOW;
	87
	88	page = (char *)__get_free_page(GFP_KERNEL);
	89	if (page) {
	90	ret = -EFAULT;
	91	if (copy_from_user(page, buf, count))
	92	goto out;
	93	ret = shost->hostt->proc_info(shost, page, &start, 0, count, 1);
	94	}
	95	out:
	96	free_page((unsigned long)page);
	97	return ret;
	98	}
	99
eb44820c RL	100	/**
	101	* scsi_proc_hostdir_add - Create directory in /proc for a scsi host
	102	* @sht: owner of this directory
	103	*
	104	* Sets sht->proc_dir to the new directory.
	105	*/
	106
1da177e4 LT	107	void scsi_proc_hostdir_add(struct scsi_host_template *sht)
	108	{
	109	if (!sht->proc_info)
	110	return;
	111
0b950672	112	mutex_lock(&global_host_template_mutex);
1da177e4 LT	113	if (!sht->present++) {
	114	sht->proc_dir = proc_mkdir(sht->proc_name, proc_scsi);
	115	if (!sht->proc_dir)
	116	printk(KERN_ERR "%s: proc_mkdir failed for %s\n",
cadbd4a5	117	__func__, sht->proc_name);
1da177e4	118	}
0b950672	119	mutex_unlock(&global_host_template_mutex);
1da177e4 LT	120	}
1da177e4 LT	121
eb44820c RL	122	/**
	123	* scsi_proc_hostdir_rm - remove directory in /proc for a scsi host
	124	* @sht: owner of directory
	125	*/
1da177e4 LT	126	void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
	127	{
	128	if (!sht->proc_info)
	129	return;
	130
0b950672	131	mutex_lock(&global_host_template_mutex);
1da177e4 LT	132	if (!--sht->present && sht->proc_dir) {
	133	remove_proc_entry(sht->proc_name, proc_scsi);
	134	sht->proc_dir = NULL;
	135	}
0b950672	136	mutex_unlock(&global_host_template_mutex);
1da177e4 LT	137	}
1da177e4 LT	138
eb44820c RL	139
	140	/**
	141	* scsi_proc_host_add - Add entry for this host to appropriate /proc dir
	142	* @shost: host to add
	143	*/
1da177e4 LT	144	void scsi_proc_host_add(struct Scsi_Host *shost)
	145	{
	146	struct scsi_host_template *sht = shost->hostt;
	147	struct proc_dir_entry *p;
	148	char name[10];
	149
	150	if (!sht->proc_dir)
	151	return;
	152
	153	sprintf(name,"%d", shost->host_no);
	154	p = create_proc_read_entry(name, S_IFREG \| S_IRUGO \| S_IWUSR,
	155	sht->proc_dir, proc_scsi_read, shost);
	156	if (!p) {
	157	printk(KERN_ERR "%s: Failed to register host %d in"
cadbd4a5	158	"%s\n", __func__, shost->host_no,
1da177e4 LT	159	sht->proc_name);
	160	return;
	161	}
	162
	163	p->write_proc = proc_scsi_write_proc;
1da177e4 LT	164	}
1da177e4 LT	165
eb44820c RL	166	/**
	167	* scsi_proc_host_rm - remove this host's entry from /proc
	168	* @shost: which host
	169	*/
1da177e4 LT	170	void scsi_proc_host_rm(struct Scsi_Host *shost)
	171	{
	172	char name[10];
	173
	174	if (!shost->hostt->proc_dir)
	175	return;
	176
	177	sprintf(name,"%d", shost->host_no);
	178	remove_proc_entry(name, shost->hostt->proc_dir);
	179	}
eb44820c RL	180	/**
	181	* proc_print_scsidevice - return data about this host
	182	* @dev: A scsi device
	183	* @data: &struct seq_file to output to.
	184	*
	185	* Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,
	186	* and revision.
	187	*/
1da177e4 LT	188	static int proc_print_scsidevice(struct device dev, void data)
1da177e4 LT	189	{
b0ed4336	190	struct scsi_device *sdev;
1da177e4 LT	191	struct seq_file *s = data;
	192	int i;
	193
b0ed4336 HR	194	if (!scsi_is_sdev_device(dev))
	195	goto out;
	196
	197	sdev = to_scsi_device(dev);
1da177e4 LT	198	seq_printf(s,
	199	"Host: scsi%d Channel: %02d Id: %02d Lun: %02d\n Vendor: ",
	200	sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
	201	for (i = 0; i < 8; i++) {
	202	if (sdev->vendor[i] >= 0x20)
	203	seq_printf(s, "%c", sdev->vendor[i]);
	204	else
	205	seq_printf(s, " ");
	206	}
	207
	208	seq_printf(s, " Model: ");
	209	for (i = 0; i < 16; i++) {
	210	if (sdev->model[i] >= 0x20)
	211	seq_printf(s, "%c", sdev->model[i]);
	212	else
	213	seq_printf(s, " ");
	214	}
	215
	216	seq_printf(s, " Rev: ");
	217	for (i = 0; i < 4; i++) {
	218	if (sdev->rev[i] >= 0x20)
	219	seq_printf(s, "%c", sdev->rev[i]);
	220	else
	221	seq_printf(s, " ");
	222	}
	223
	224	seq_printf(s, "\n");
	225
4ff36718	226	seq_printf(s, " Type: %s ", scsi_device_type(sdev->type));
74feb53e AS	227	seq_printf(s, " ANSI SCSI revision: %02x",
74feb53e AS	228	sdev->scsi_level - (sdev->scsi_level > 1));
1da177e4 LT	229	if (sdev->scsi_level == 2)
	230	seq_printf(s, " CCS\n");
	231	else
	232	seq_printf(s, "\n");
	233
b0ed4336	234	out:
1da177e4 LT	235	return 0;
	236	}
	237
eb44820c RL	238	/**
	239	* scsi_add_single_device - Respond to user request to probe for/add device
	240	* @host: user-supplied decimal integer
	241	* @channel: user-supplied decimal integer
	242	* @id: user-supplied decimal integer
	243	* @lun: user-supplied decimal integer
	244	*
	245	* Description: called by writing "scsi add-single-device" to /proc/scsi/scsi.
	246	*
	247	* does scsi_host_lookup() and either user_scan() if that transport
	248	* type supports it, or else scsi_scan_host_selected()
	249	*
	250	* Note: this seems to be aimed exclusively at SCSI parallel busses.
	251	*/
	252
1da177e4 LT	253	static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
	254	{
	255	struct Scsi_Host *shost;
	256	int error = -ENXIO;
	257
	258	shost = scsi_host_lookup(host);
315cb0ad JS	259	if (!shost)
315cb0ad JS	260	return error;
1da177e4	261
e02f3f59 CH	262	if (shost->transportt->user_scan)
	263	error = shost->transportt->user_scan(shost, channel, id, lun);
	264	else
	265	error = scsi_scan_host_selected(shost, channel, id, lun, 1);
1da177e4 LT	266	scsi_host_put(shost);
	267	return error;
	268	}
	269
eb44820c RL	270	/**
	271	* scsi_remove_single_device - Respond to user request to remove a device
	272	* @host: user-supplied decimal integer
	273	* @channel: user-supplied decimal integer
	274	* @id: user-supplied decimal integer
	275	* @lun: user-supplied decimal integer
	276	*
	277	* Description: called by writing "scsi remove-single-device" to
	278	* /proc/scsi/scsi. Does a scsi_device_lookup() and scsi_remove_device()
	279	*/
1da177e4 LT	280	static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
	281	{
	282	struct scsi_device *sdev;
	283	struct Scsi_Host *shost;
	284	int error = -ENXIO;
	285
	286	shost = scsi_host_lookup(host);
315cb0ad JS	287	if (!shost)
315cb0ad JS	288	return error;
1da177e4 LT	289	sdev = scsi_device_lookup(shost, channel, id, lun);
	290	if (sdev) {
	291	scsi_remove_device(sdev);
	292	scsi_device_put(sdev);
	293	error = 0;
	294	}
	295
	296	scsi_host_put(shost);
	297	return error;
	298	}
	299
eb44820c RL	300	/**
	301	* proc_scsi_write - handle writes to /proc/scsi/scsi
	302	* @file: not used
	303	* @buf: buffer to write
	304	* @length: length of buf, at most PAGE_SIZE
	305	* @ppos: not used
	306	*
	307	* Description: this provides a legacy mechanism to add or remove devices by
	308	* Host, Channel, ID, and Lun. To use,
	309	* "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
	310	* "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
	311	* "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
	312	*
	313	* Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
	314	* SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
	315	* provide a unique identifier and nothing more.
	316	*/
	317
	318
1da177e4 LT	319	static ssize_t proc_scsi_write(struct file file, const char __user buf,
	320	size_t length, loff_t *ppos)
	321	{
	322	int host, channel, id, lun;
	323	char buffer, p;
	324	int err;
	325
	326	if (!buf \|\| length > PAGE_SIZE)
	327	return -EINVAL;
	328
	329	buffer = (char *)__get_free_page(GFP_KERNEL);
	330	if (!buffer)
	331	return -ENOMEM;
	332
	333	err = -EFAULT;
	334	if (copy_from_user(buffer, buf, length))
	335	goto out;
	336
	337	err = -EINVAL;
	338	if (length < PAGE_SIZE)
	339	buffer[length] = '\0';
	340	else if (buffer[PAGE_SIZE-1])
	341	goto out;
	342
	343	/*
	344	* Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
	345	* with "0 1 2 3" replaced by your "Host Channel Id Lun".
	346	*/
	347	if (!strncmp("scsi add-single-device", buffer, 22)) {
	348	p = buffer + 23;
	349
	350	host = simple_strtoul(p, &p, 0);
	351	channel = simple_strtoul(p + 1, &p, 0);
	352	id = simple_strtoul(p + 1, &p, 0);
	353	lun = simple_strtoul(p + 1, &p, 0);
	354
	355	err = scsi_add_single_device(host, channel, id, lun);
1da177e4 LT	356
	357	/*
	358	* Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
	359	* with "0 1 2 3" replaced by your "Host Channel Id Lun".
	360	*/
	361	} else if (!strncmp("scsi remove-single-device", buffer, 25)) {
	362	p = buffer + 26;
	363
	364	host = simple_strtoul(p, &p, 0);
	365	channel = simple_strtoul(p + 1, &p, 0);
	366	id = simple_strtoul(p + 1, &p, 0);
	367	lun = simple_strtoul(p + 1, &p, 0);
	368
	369	err = scsi_remove_single_device(host, channel, id, lun);
	370	}
	371
2ca48a13 JB	372	/*
	373	* convert success returns so that we return the
	374	* number of bytes consumed.
	375	*/
	376	if (!err)
	377	err = length;
	378
1da177e4 LT	379	out:
	380	free_page((unsigned long)buffer);
	381	return err;
	382	}
	383
eb44820c RL	384	/**
	385	* proc_scsi_show - show contents of /proc/scsi/scsi (attached devices)
	386	* @s: output goes here
	387	* @p: not used
	388	*/
1da177e4 LT	389	static int proc_scsi_show(struct seq_file s, void p)
	390	{
	391	seq_printf(s, "Attached devices:\n");
	392	bus_for_each_dev(&scsi_bus_type, NULL, s, proc_print_scsidevice);
	393	return 0;
	394	}
	395
eb44820c RL	396	/**
	397	* proc_scsi_open - glue function
	398	* @inode: not used
	399	* @file: passed to single_open()
	400	*
	401	* Associates proc_scsi_show with this file
	402	*/
1da177e4 LT	403	static int proc_scsi_open(struct inode inode, struct file file)
	404	{
	405	/*
eb44820c	406	* We don't really need this for the write case but it doesn't
1da177e4 LT	407	* harm either.
	408	*/
	409	return single_open(file, proc_scsi_show, NULL);
	410	}
	411
00977a59	412	static const struct file_operations proc_scsi_operations = {
a973909f	413	.owner = THIS_MODULE,
1da177e4 LT	414	.open = proc_scsi_open,
	415	.read = seq_read,
	416	.write = proc_scsi_write,
	417	.llseek = seq_lseek,
	418	.release = single_release,
	419	};
	420
eb44820c RL	421	/**
	422	* scsi_init_procfs - create scsi and scsi/scsi in procfs
	423	*/
1da177e4 LT	424	int __init scsi_init_procfs(void)
	425	{
	426	struct proc_dir_entry *pde;
	427
	428	proc_scsi = proc_mkdir("scsi", NULL);
	429	if (!proc_scsi)
	430	goto err1;
	431
a973909f	432	pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
1da177e4 LT	433	if (!pde)
1da177e4 LT	434	goto err2;
1da177e4 LT	435
	436	return 0;
	437
	438	err2:
	439	remove_proc_entry("scsi", NULL);
	440	err1:
	441	return -ENOMEM;
	442	}
	443
eb44820c RL	444	/**
	445	* scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
	446	*/
1da177e4 LT	447	void scsi_exit_procfs(void)
	448	{
	449	remove_proc_entry("scsi/scsi", NULL);
	450	remove_proc_entry("scsi", NULL);
	451	}