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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/usb/storage/scsiglue.c
Initial import
Diffstat (limited to 'drivers/usb/storage/scsiglue.c')
-rw-r--r--drivers/usb/storage/scsiglue.c602
1 files changed, 602 insertions, 0 deletions
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
new file mode 100644
index 000000000..0e400f382
--- /dev/null
+++ b/drivers/usb/storage/scsiglue.c
@@ -0,0 +1,602 @@
+/* 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.
+ *
+ * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
+ * information about this driver.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#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);
+
+ /*
+ * 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 DMA-alignment requirements: Although the
+ * starting address of each scatter-gather element doesn't matter,
+ * the length of each element except the last must be divisible
+ * by the Bulk maxpacket value. There's currently no way to
+ * express this by block-layer constraints, so we'll cop out
+ * and simply require addresses to be aligned at 512-byte
+ * boundaries. This is okay since most block I/O involves
+ * hardware sectors that are multiples of 512 bytes in length,
+ * and since host controllers up through USB 2.0 have maxpacket
+ * values no larger than 512.
+ *
+ * But it doesn't suffice for Wireless USB, where Bulk maxpacket
+ * values can be as large as 2048. To make that work properly
+ * will require changes to the block layer.
+ */
+ 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_CACHE_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);
+ }
+
+ /* 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 */
+ sdev->skip_vpd_pages = 1;
+
+ /* 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 */
+ if (sdev->scsi_level > SCSI_SPC_2)
+ 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;
+
+ } 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;
+ }
+
+ /* 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;
+}
+
+/* we use this macro to help us write into the buffer */
+#undef SPRINTF
+#define SPRINTF(args...) seq_printf(m, ## args)
+
+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 */
+ SPRINTF(" 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";
+ SPRINTF(" 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";
+ SPRINTF(" Product: %s\n", string);
+ if (us->pusb_dev->serial)
+ string = us->pusb_dev->serial;
+ else
+ string = "None";
+ SPRINTF("Serial Number: %s\n", string);
+
+ /* show the protocol and transport */
+ SPRINTF(" Protocol: %s\n", us->protocol_name);
+ SPRINTF(" Transport: %s\n", us->transport_name);
+
+ /* show the device flags */
+ SPRINTF(" 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
+ */
+
+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,
+ .cmd_per_lun = 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 = SCSI_MAX_SG_CHAIN_SEGMENTS,
+
+ /* limit the total size of a transfer to 120 KB */
+ .max_sectors = 240,
+
+ /* merge commands... this seems to help performance, but
+ * periodically someone should test to see which setting is more
+ * optimal.
+ */
+ .use_clustering = 1,
+
+ /* 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
+};
+
+/* 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);