linux-hardened/drivers/scsi/scsi_proc.c
James Bottomley 2ca48a1321 [SCSI] fix proc_scsi_write to return "length" on success with remove-single-device case
Problem spotted by: Suzuki K P <suzuki@in.ibm.com>

A zero return on success isn't correct for filesystem write functions.
They should either return negative error or the length of bytes
consumed.  Add code to convert our zero on success error return to
return the length of bytes passed in.

This fixes the following:

$ echo "scsi remove-single-device 0 0 3 0" > /proc/scsi/scsi
bash: echo: write error: No such device or address"

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-10 10:22:30 -05:00

346 lines
7.8 KiB
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/slab.h>
#include <linux/proc_fs.h>
#include <linux/errno.h>
#include <linux/blkdev.h>
#include <linux/seq_file.h>
#include <linux/mutex.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 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;
}
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;
}
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",
__FUNCTION__, sht->proc_name);
else
sht->proc_dir->owner = sht->module;
}
mutex_unlock(&global_host_template_mutex);
}
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);
}
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", __FUNCTION__, shost->host_no,
sht->proc_name);
return;
}
p->write_proc = proc_scsi_write_proc;
p->owner = sht->module;
}
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);
}
static int proc_print_scsidevice(struct device *dev, void *data)
{
struct scsi_device *sdev = to_scsi_device(dev);
struct seq_file *s = data;
int i;
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 ",
sdev->type < MAX_SCSI_DEVICE_CODE ?
scsi_device_types[(int) sdev->type] : "Unknown ");
seq_printf(s, " ANSI"
" SCSI revision: %02x", (sdev->scsi_level - 1) ?
sdev->scsi_level - 1 : 1);
if (sdev->scsi_level == 2)
seq_printf(s, " CCS\n");
else
seq_printf(s, "\n");
return 0;
}
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 (IS_ERR(shost))
return PTR_ERR(shost);
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;
}
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 (IS_ERR(shost))
return PTR_ERR(shost);
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;
}
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 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;
}
static int proc_scsi_open(struct inode *inode, struct file *file)
{
/*
* We don't really needs this for the write case but it doesn't
* harm either.
*/
return single_open(file, proc_scsi_show, NULL);
}
static struct file_operations proc_scsi_operations = {
.open = proc_scsi_open,
.read = seq_read,
.write = proc_scsi_write,
.llseek = seq_lseek,
.release = single_release,
};
int __init scsi_init_procfs(void)
{
struct proc_dir_entry *pde;
proc_scsi = proc_mkdir("scsi", NULL);
if (!proc_scsi)
goto err1;
pde = create_proc_entry("scsi/scsi", 0, NULL);
if (!pde)
goto err2;
pde->proc_fops = &proc_scsi_operations;
return 0;
err2:
remove_proc_entry("scsi", NULL);
err1:
return -ENOMEM;
}
void scsi_exit_procfs(void)
{
remove_proc_entry("scsi/scsi", NULL);
remove_proc_entry("scsi", NULL);
}