// SPDX-License-Identifier: GPL-2.0+
/*
* Driver for USB Mass Storage compliant devices
* SCSI layer glue code
*
* Current development and maintenance by:
* (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
*
* Developed with the assistance of:
* (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
* (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
*
* Initial work by:
* (c) 1999 Michael Gee (michael@linuxspecific.com)
*
* This driver is based on the 'USB Mass Storage Class' document. This
* describes in detail the protocol used to communicate with such
* devices. Clearly, the designers had SCSI and ATAPI commands in
* mind when they created this document. The commands are all very
* similar to commands in the SCSI-II and ATAPI specifications.
*
* It is important to note that in a number of cases this class
* exhibits class-specific exemptions from the USB specification.
* Notably the usage of NAK, STALL and ACK differs from the norm, in
* that they are used to communicate wait, failed and OK on commands.
*
* Also, for certain devices, the interrupt endpoint is used to convey
* status of a command.
*/
#include <linux/module.h>
#include <linux/mutex.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_devinfo.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include "usb.h"
#include "scsiglue.h"
#include "debug.h"
#include "transport.h"
#include "protocol.h"
/*
* Vendor IDs for companies that seem to include the READ CAPACITY bug
* in all their devices
*/
#define VENDOR_ID_NOKIA 0x0421
#define VENDOR_ID_NIKON 0x04b0
#define VENDOR_ID_PENTAX 0x0a17
#define VENDOR_ID_MOTOROLA 0x22b8
/***********************************************************************
* Host functions
***********************************************************************/
static const char* host_info(struct Scsi_Host *host)
{
struct us_data *us = host_to_us(host);
return us->scsi_name;
}
static int slave_alloc (struct scsi_device *sdev)
{
struct us_data *us = host_to_us(sdev->host);
int maxp;
/*
* Set the INQUIRY transfer length to 36. We don't use any of
* the extra data and many devices choke if asked for more or
* less than 36 bytes.
*/
sdev->inquiry_len = 36;
/*
* USB has unusual scatter-gather requirements: the length of each
* scatterlist element except the last must be divisible by the
* Bulk maxpacket value. Fortunately this value is always a
* power of 2. Inform the block layer about this requirement.
*/
maxp = usb_maxpacket(us->pusb_dev, us->recv_bulk_pipe, 0);
blk_queue_virt_boundary(sdev->request_queue, maxp - 1);
/*
* Some host controllers may have alignment requirements.
* We'll play it safe by requiring 512-byte alignment always.
*/
blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
/* Tell the SCSI layer if we know there is more than one LUN */
if (us->protocol == USB_PR_BULK && us->max_lun > 0)
sdev->sdev_bflags |= BLIST_FORCELUN;
return 0;
}
static int slave_configure(struct scsi_device *sdev)
{
struct us_data *us = host_to_us(sdev->host);
/*
* Many devices have trouble transferring more than 32KB at a time,
* while others have trouble with more than 64K. At this time we
* are limiting both to 32K (64 sectores).
*/
if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
unsigned int max_sectors = 64;
if (us->fflags & US_FL_MAX_SECTORS_MIN)
max_sectors = PAGE_SIZE >> 9;
if (queue_max_hw_sectors(sdev->request_queue) > max_sectors)
blk_queue_max_hw_sectors(sdev->request_queue,
max_sectors);
} else if (sdev->type == TYPE_TAPE) {
/*
* Tapes need much higher max_sector limits, so just
* raise it to the maximum possible (4 GB / 512) and
* let the queue segment size sort out the real limit.
*/
blk_queue_max_hw_sectors(sdev->request_queue, 0x7FFFFF);
} else if (us->pusb_dev->speed >= USB_SPEED_SUPER) {
/*
* USB3 devices will be limited to 2048 sectors. This gives us
* better throughput on most devices.
*/
blk_queue_max_hw_sectors(sdev->request_queue, 2048);
}
/*
* Some USB host controllers can't do DMA; they have to use PIO.
* They indicate this by setting their dma_mask to NULL. For
* such controllers we need to make sure the block layer sets
* up bounce buffers in addressable memory.
*/
if (!us->pusb_dev->bus->controller->dma_mask)
blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
/*
* We can't put these settings in slave_alloc() because that gets
* called before the device type is known. Consequently these
* settings can't be overridden via the scsi devinfo mechanism.
*/
if (sdev->type == TYPE_DISK) {
/*
* Some vendors seem to put the READ CAPACITY bug into
* all their devices -- primarily makers of cell phones
* and digital cameras. Since these devices always use
* flash media and can be expected to have an even number
* of sectors, we will always enable the CAPACITY_HEURISTICS
* flag unless told otherwise.
*/
switch (le16_to_cpu(us->pusb_dev->descriptor.idVendor)) {
case VENDOR_ID_NOKIA:
case VENDOR_ID_NIKON:
case VENDOR_ID_PENTAX:
case VENDOR_ID_MOTOROLA:
if (!(us->fflags & (US_FL_FIX_CAPACITY |
US_FL_CAPACITY_OK)))
us->fflags |= US_FL_CAPACITY_HEURISTICS;
break;
}
/*
* Disk-type devices use MODE SENSE(6) if the protocol
* (SubClass) is Transparent SCSI, otherwise they use
* MODE SENSE(10).
*/
if (us->subclass != USB_SC_SCSI && us->subclass != USB_SC_CYP_ATACB)
sdev->use_10_for_ms = 1;
/*
*Many disks only accept MODE SENSE transfer lengths of
* 192 bytes (that's what Windows uses).
*/
sdev->use_192_bytes_for_3f = 1;
/*
* Some devices don't like MODE SENSE with page=0x3f,
* which is the command used for checking if a device
* is write-protected. Now that we tell the sd driver
* to do a 192-byte transfer with this command the
* majority of devices work fine, but a few still can't
* handle it. The sd driver will simply assume those
* devices are write-enabled.
*/
if (us->fflags & US_FL_NO_WP_DETECT)
sdev->skip_ms_page_3f = 1;
/*
* A number of devices have problems with MODE SENSE for
* page x08, so we will skip it.
*/
sdev->skip_ms_page_8 = 1;
/*
* Some devices don't handle VPD pages correctly, so skip vpd
* pages if not forced by SCSI layer.
*/
sdev->skip_vpd_pages = !sdev->try_vpd_pages;
/* Do not attempt to use REPORT SUPPORTED OPERATION CODES */
sdev->no_report_opcodes = 1;
/* Do not attempt to use WRITE SAME */
sdev->no_write_same = 1;
/*
* Some disks return the total number of blocks in response
* to READ CAPACITY rather than the highest block number.
* If this device makes that mistake, tell the sd driver.
*/
if (us->fflags & US_FL_FIX_CAPACITY)
sdev->fix_capacity = 1;
/*
* A few disks have two indistinguishable version, one of
* which reports the correct capacity and the other does not.
* The sd driver has to guess which is the case.
*/
if (us->fflags & US_FL_CAPACITY_HEURISTICS)
sdev->guess_capacity = 1;
/* Some devices cannot handle READ_CAPACITY_16 */
if (us->fflags & US_FL_NO_READ_CAPACITY_16)
sdev->no_read_capacity_16 = 1;
/*
* Many devices do not respond properly to READ_CAPACITY_16.
* Tell the SCSI layer to try READ_CAPACITY_10 first.
* However some USB 3.0 drive enclosures return capacity
* modulo 2TB. Those must use READ_CAPACITY_16
*/
if (!(us->fflags & US_FL_NEEDS_CAP16))
sdev->try_rc_10_first = 1;
/*
* assume SPC3 or latter devices support sense size > 18
* unless US_FL_BAD_SENSE quirk is specified.
*/
if (sdev->scsi_level > SCSI_SPC_2 &&
!(us->fflags & US_FL_BAD_SENSE))
us->fflags |= US_FL_SANE_SENSE;
/*
* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
* Hardware Error) when any low-level error occurs,
* recoverable or not. Setting this flag tells the SCSI
* midlayer to retry such commands, which frequently will
* succeed and fix the error. The worst this can lead to
* is an occasional series of retries that will all fail.
*/
sdev->retry_hwerror = 1;
/*
* USB disks should allow restart. Some drives spin down
* automatically, requiring a START-STOP UNIT command.
*/
sdev->allow_restart = 1;
/*
* Some USB cardreaders have trouble reading an sdcard's last
* sector in a larger then 1 sector read, since the performance
* impact is negligible we set this flag for all USB disks
*/
sdev->last_sector_bug = 1;
/*
* Enable last-sector hacks for single-target devices using
* the Bulk-only transport, unless we already know the
* capacity will be decremented or is correct.
*/
if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
US_FL_SCM_MULT_TARG)) &&
us->protocol == USB_PR_BULK)
us->use_last_sector_hacks = 1;
/* Check if write cache default on flag is set or not */
if (us->fflags & US_FL_WRITE_CACHE)
sdev->wce_default_on = 1;
/* A few buggy USB-ATA bridges don't understand FUA */
if (us->fflags & US_FL_BROKEN_FUA)
sdev->broken_fua = 1;
/* Some even totally fail to indicate a cache */
if (us->fflags & US_FL_ALWAYS_SYNC) {
/* don't read caching information */
sdev->skip_ms_page_8 = 1;
sdev->skip_ms_page_3f = 1;
/* assume sync is needed */
sdev->wce_default_on = 1;
}
} else {
/*
* Non-disk-type devices don't need to blacklist any pages
* or to force 192-byte transfer lengths for MODE SENSE.
* But they do need to use MODE SENSE(10).
*/
sdev->use_10_for_ms = 1;
/* Some (fake) usb cdrom devices don't like READ_DISC_INFO */
if (us->fflags & US_FL_NO_READ_DISC_INFO)
sdev->no_read_disc_info = 1;
}
/*
* The CB and CBI transports have no way to pass LUN values
* other than the bits in the second byte of a CDB. But those
* bits don't get set to the LUN value if the device reports
* scsi_level == 0 (UNKNOWN). Hence such devices must necessarily
* be single-LUN.
*/
if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
sdev->scsi_level == SCSI_UNKNOWN)
us->max_lun = 0;
/*
* Some devices choke when they receive a PREVENT-ALLOW MEDIUM
* REMOVAL command, so suppress those commands.
*/
if (us->fflags & US_FL_NOT_LOCKABLE)
sdev->lockable = 0;
/*
* this is to satisfy the compiler, tho I don't think the
* return code is ever checked anywhere.
*/
return 0;
}
static int target_alloc(struct scsi_target *starget)
{
struct us_data *us = host_to_us(dev_to_shost(starget->dev.parent));
/*
* Some USB drives don't support REPORT LUNS, even though they
* report a SCSI revision level above 2. Tell the SCSI layer
* not to issue that command; it will perform a normal sequential
* scan instead.
*/
starget->no_report_luns = 1;
/*
* The UFI spec treats the Peripheral Qualifier bits in an
* INQUIRY result as reserved and requires devices to set them
* to 0. However the SCSI spec requires these bits to be set
* to 3 to indicate when a LUN is not present.
*
* Let the scanning code know if this target merely sets
* Peripheral Device Type to 0x1f to indicate no LUN.
*/
if (us->subclass == USB_SC_UFI)
starget->pdt_1f_for_no_lun = 1;
return 0;
}
/* queue a command */
/* This is always called with scsi_lock(host) held */
static int queuecommand_lck(struct scsi_cmnd *srb,
void (*done)(struct scsi_cmnd *))
{
struct us_data *us = host_to_us(srb->device->host);
/* check for state-transition errors */
if (us->srb != NULL) {
printk(KERN_ERR USB_STORAGE "Error in %s: us->srb = %p\n",
__func__, us->srb);
return SCSI_MLQUEUE_HOST_BUSY;
}
/* fail the command if we are disconnecting */
if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
usb_stor_dbg(us, "Fail command during disconnect\n");
srb->result = DID_NO_CONNECT << 16;
done(srb);
return 0;
}
if ((us->fflags & US_FL_NO_ATA_1X) &&
(srb->cmnd[0] == ATA_12 || srb->cmnd[0] == ATA_16)) {
memcpy(srb->sense_buffer, usb_stor_sense_invalidCDB,
sizeof(usb_stor_sense_invalidCDB));
srb->result = SAM_STAT_CHECK_CONDITION;
done(srb);
return 0;
}
/* enqueue the command and wake up the control thread */
srb->scsi_done = done;
us->srb = srb;
complete(&us->cmnd_ready);
return 0;
}
static DEF_SCSI_QCMD(queuecommand)
/***********************************************************************
* Error handling functions
***********************************************************************/
/* Command timeout and abort */
static int command_abort(struct scsi_cmnd *srb)
{
struct us_data *us = host_to_us(srb->device->host);
usb_stor_dbg(us, "%s called\n", __func__);
/*
* us->srb together with the TIMED_OUT, RESETTING, and ABORTING
* bits are protected by the host lock.
*/
scsi_lock(us_to_host(us));
/* Is this command still active? */
if (us->srb != srb) {
scsi_unlock(us_to_host(us));
usb_stor_dbg(us, "-- nothing to abort\n");
return FAILED;
}
/*
* Set the TIMED_OUT bit. Also set the ABORTING bit, but only if
* a device reset isn't already in progress (to avoid interfering
* with the reset). Note that we must retain the host lock while
* calling usb_stor_stop_transport(); otherwise it might interfere
* with an auto-reset that begins as soon as we release the lock.
*/
set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
set_bit(US_FLIDX_ABORTING, &us->dflags);
usb_stor_stop_transport(us);
}
scsi_unlock(us_to_host(us));
/* Wait for the aborted command to finish */
wait_for_completion(&us->notify);
return SUCCESS;
}
/*
* This invokes the transport reset mechanism to reset the state of the
* device
*/
static int device_reset(struct scsi_cmnd *srb)
{
struct us_data *us = host_to_us(srb->device->host);
int result;
usb_stor_dbg(us, "%s called\n", __func__);
/* lock the device pointers and do the reset */
mutex_lock(&(us->dev_mutex));
result = us->transport_reset(us);
mutex_unlock(&us->dev_mutex);
return result < 0 ? FAILED : SUCCESS;
}
/* Simulate a SCSI bus reset by resetting the device's USB port. */
static int bus_reset(struct scsi_cmnd *srb)
{
struct us_data *us = host_to_us(srb->device->host);
int result;
usb_stor_dbg(us, "%s called\n", __func__);
result = usb_stor_port_reset(us);
return result < 0 ? FAILED : SUCCESS;
}
/*
* Report a driver-initiated device reset to the SCSI layer.
* Calling this for a SCSI-initiated reset is unnecessary but harmless.
* The caller must own the SCSI host lock.
*/
void usb_stor_report_device_reset(struct us_data *us)
{
int i;
struct Scsi_Host *host = us_to_host(us);
scsi_report_device_reset(host, 0, 0);
if (us->fflags & US_FL_SCM_MULT_TARG) {
for (i = 1; i < host->max_id; ++i)
scsi_report_device_reset(host, 0, i);
}
}
/*
* Report a driver-initiated bus reset to the SCSI layer.
* Calling this for a SCSI-initiated reset is unnecessary but harmless.
* The caller must not own the SCSI host lock.
*/
void usb_stor_report_bus_reset(struct us_data *us)
{
struct Scsi_Host *host = us_to_host(us);
scsi_lock(host);
scsi_report_bus_reset(host, 0);
scsi_unlock(host);
}
/***********************************************************************
* /proc/scsi/ functions
***********************************************************************/
static int write_info(struct Scsi_Host *host, char *buffer, int length)
{
/* if someone is sending us data, just throw it away */
return length;
}
static int show_info (struct seq_file *m, struct Scsi_Host *host)
{
struct us_data *us = host_to_us(host);
const char *string;
/* print the controller name */
seq_printf(m, " Host scsi%d: usb-storage\n", host->host_no);
/* print product, vendor, and serial number strings */
if (us->pusb_dev->manufacturer)
string = us->pusb_dev->manufacturer;
else if (us->unusual_dev->vendorName)
string = us->unusual_dev->vendorName;
else
string = "Unknown";
seq_printf(m, " Vendor: %s\n", string);
if (us->pusb_dev->product)
string = us->pusb_dev->product;
else if (us->unusual_dev->productName)
string = us->unusual_dev->productName;
else
string = "Unknown";
seq_printf(m, " Product: %s\n", string);
if (us->pusb_dev->serial)
string = us->pusb_dev->serial;
else
string = "None";
seq_printf(m, "Serial Number: %s\n", string);
/* show the protocol and transport */
seq_printf(m, " Protocol: %s\n", us->protocol_name);
seq_printf(m, " Transport: %s\n", us->transport_name);
/* show the device flags */
seq_printf(m, " Quirks:");
#define US_FLAG(name, value) \
if (us->fflags & value) seq_printf(m, " " #name);
US_DO_ALL_FLAGS
#undef US_FLAG
seq_putc(m, '\n');
return 0;
}
/***********************************************************************
* Sysfs interface
***********************************************************************/
/* Output routine for the sysfs max_sectors file */
static ssize_t max_sectors_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct scsi_device *sdev = to_scsi_device(dev);
return sprintf(buf, "%u\n", queue_max_hw_sectors(sdev->request_queue));
}
/* Input routine for the sysfs max_sectors file */
static ssize_t max_sectors_store(struct device *dev, struct device_attribute *attr, const char *buf,
size_t count)
{
struct scsi_device *sdev = to_scsi_device(dev);
unsigned short ms;
if (sscanf(buf, "%hu", &ms) > 0) {
blk_queue_max_hw_sectors(sdev->request_queue, ms);
return count;
}
return -EINVAL;
}
static DEVICE_ATTR_RW(max_sectors);
static struct device_attribute *sysfs_device_attr_list[] = {
&dev_attr_max_sectors,
NULL,
};
/*
* this defines our host template, with which we'll allocate hosts
*/
static const struct scsi_host_template usb_stor_host_template = {
/* basic userland interface stuff */
.name = "usb-storage",
.proc_name = "usb-storage",
.show_info = show_info,
.write_info = write_info,
.info = host_info,
/* command interface -- queued only */
.queuecommand = queuecommand,
/* error and abort handlers */
.eh_abort_handler = command_abort,
.eh_device_reset_handler = device_reset,
.eh_bus_reset_handler = bus_reset,
/* queue commands only, only one command per LUN */
.can_queue = 1,
/* unknown initiator id */
.this_id = -1,
.slave_alloc = slave_alloc,
.slave_configure = slave_configure,
.target_alloc = target_alloc,
/* lots of sg segments can be handled */
.sg_tablesize = SG_MAX_SEGMENTS,
/*
* Limit the total size of a transfer to 120 KB.
*
* Some devices are known to choke with anything larger. It seems like
* the problem stems from the fact that original IDE controllers had
* only an 8-bit register to hold the number of sectors in one transfer
* and even those couldn't handle a full 256 sectors.
*
* Because we want to make sure we interoperate with as many devices as
* possible, we will maintain a 240 sector transfer size limit for USB
* Mass Storage devices.
*
* Tests show that other operating have similar limits with Microsoft
* Windows 7 limiting transfers to 128 sectors for both USB2 and USB3
* and Apple Mac OS X 10.11 limiting transfers to 256 sectors for USB2
* and 2048 for USB3 devices.
*/
.max_sectors = 240,
/* emulated HBA */
.emulated = 1,
/* we do our own delay after a device or bus reset */
.skip_settle_delay = 1,
/* sysfs device attributes */
.sdev_attrs = sysfs_device_attr_list,
/* module management */
.module = THIS_MODULE
};
void usb_stor_host_template_init(struct scsi_host_template *sht,
const char *name, struct module *owner)
{
*sht = usb_stor_host_template;
sht->name = name;
sht->proc_name = name;
sht->module = owner;
}
EXPORT_SYMBOL_GPL(usb_stor_host_template_init);
/* To Report "Illegal Request: Invalid Field in CDB */
unsigned char usb_stor_sense_invalidCDB[18] = {
[0] = 0x70, /* current error */
[2] = ILLEGAL_REQUEST, /* Illegal Request = 0x05 */
[7] = 0x0a, /* additional length */
[12] = 0x24 /* Invalid Field in CDB */
};
EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);
