#include <linux/slab.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
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;
+
+ /*
+ * The UFI spec treates 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 == US_SC_UFI)
+ sdev->sdev_target->pdt_1f_for_no_lun = 1;
+
return 0;
}
* data comes from.
*/
if (sdev->scsi_level < SCSI_2)
- sdev->scsi_level = SCSI_2;
-
- /* According to the technical support people at Genesys Logic,
- * devices using their chips have problems transferring more than
- * 32 KB at a time. In practice people have found that 64 KB
- * works okay and that's what Windows does. But we'll be
- * conservative; people can always use the sysfs interface to
- * increase max_sectors. */
- if (le16_to_cpu(us->pusb_dev->descriptor.idVendor) == USB_VENDOR_ID_GENESYS &&
+ sdev->scsi_level = sdev->sdev_target->scsi_level = SCSI_2;
+
+ /* Many devices have trouble transfering 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->flags & US_FL_MAX_SECTORS_64) &&
sdev->request_queue->max_sectors > 64)
blk_queue_max_sectors(sdev->request_queue, 64);
* If this device makes that mistake, tell the sd driver. */
if (us->flags & US_FL_FIX_CAPACITY)
sdev->fix_capacity = 1;
+
+ /* Some devices report a SCSI revision level above 2 but are
+ * unable to handle the REPORT LUNS command (for which
+ * support is mandatory at level 3). Since we already have
+ * a Get-Max-LUN request, we won't lose much by setting the
+ * revision level down to 2. The only devices that would be
+ * affected are those with sparse LUNs. */
+ sdev->scsi_level = sdev->sdev_target->scsi_level = SCSI_2;
+
+ /* 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;
+
} else {
/* Non-disk-type devices don't need to blacklist any pages
***********************************************************************/
/* Command timeout and abort */
-/* This is always called with scsi_lock(host) held */
static int command_abort(struct scsi_cmnd *srb)
{
struct us_data *us = host_to_us(srb->device->host);
US_DEBUGP("%s called\n", __FUNCTION__);
+ /* 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));
US_DEBUGP ("-- 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). To prevent races with auto-reset, we must
- * stop any ongoing USB transfers while still holding the host
- * lock. */
+ * 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->flags);
if (!test_bit(US_FLIDX_RESETTING, &us->flags)) {
set_bit(US_FLIDX_ABORTING, &us->flags);
/* Wait for the aborted command to finish */
wait_for_completion(&us->notify);
-
- /* Reacquire the lock and allow USB transfers to resume */
- scsi_lock(us_to_host(us));
- clear_bit(US_FLIDX_ABORTING, &us->flags);
- clear_bit(US_FLIDX_TIMED_OUT, &us->flags);
return SUCCESS;
}
/* This invokes the transport reset mechanism to reset the state of the
* device */
-/* This is always called with scsi_lock(host) held */
static int device_reset(struct scsi_cmnd *srb)
{
struct us_data *us = host_to_us(srb->device->host);
US_DEBUGP("%s called\n", __FUNCTION__);
- scsi_unlock(us_to_host(us));
-
/* lock the device pointers and do the reset */
- down(&(us->dev_semaphore));
- if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
- result = FAILED;
- US_DEBUGP("No reset during disconnect\n");
- } else
- result = us->transport_reset(us);
- up(&(us->dev_semaphore));
+ mutex_lock(&(us->dev_mutex));
+ result = us->transport_reset(us);
+ mutex_unlock(&us->dev_mutex);
- /* lock the host for the return */
- scsi_lock(us_to_host(us));
- return result;
+ return result < 0 ? FAILED : SUCCESS;
}
-/* This resets the device's USB port. */
-/* It refuses to work if there's more than one interface in
- * the device, so that other users are not affected. */
-/* This is always called with scsi_lock(host) held */
+/* 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, rc;
+ int result;
US_DEBUGP("%s called\n", __FUNCTION__);
-
- scsi_unlock(us_to_host(us));
-
- /* The USB subsystem doesn't handle synchronisation between
- * a device's several drivers. Therefore we reset only devices
- * with just one interface, which we of course own. */
-
- down(&(us->dev_semaphore));
- if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
- result = -EIO;
- US_DEBUGP("No reset during disconnect\n");
- } else if (us->pusb_dev->actconfig->desc.bNumInterfaces != 1) {
- result = -EBUSY;
- US_DEBUGP("Refusing to reset a multi-interface device\n");
- } else {
- rc = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
- if (rc < 0) {
- US_DEBUGP("unable to lock device for reset: %d\n", rc);
- result = rc;
- } else {
- result = usb_reset_device(us->pusb_dev);
- if (rc)
- usb_unlock_device(us->pusb_dev);
- US_DEBUGP("usb_reset_device returns %d\n", result);
- }
- }
- up(&(us->dev_semaphore));
-
- /* lock the host for the return */
- scsi_lock(us_to_host(us));
+ result = usb_stor_port_reset(us);
return result < 0 ? FAILED : SUCCESS;
}
}
}
+/* Report a driver-initiated bus 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_bus_reset(struct us_data *us)
+{
+ scsi_report_bus_reset(us_to_host(us), 0);
+}
+
/***********************************************************************
* /proc/scsi/ functions
***********************************************************************/
***********************************************************************/
/* Output routine for the sysfs max_sectors file */
-static ssize_t show_max_sectors(struct device *dev, char *buf)
+static ssize_t show_max_sectors(struct device *dev, struct device_attribute *attr, char *buf)
{
struct scsi_device *sdev = to_scsi_device(dev);
}
/* Input routine for the sysfs max_sectors file */
-static ssize_t store_max_sectors(struct device *dev, const char *buf,
+static ssize_t store_max_sectors(struct device *dev, struct device_attribute *attr, const char *buf,
size_t count)
{
struct scsi_device *sdev = to_scsi_device(dev);
git://git.onelab.eu / linux-2.6.git / blobdiff