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path: root/drivers/block/ub.c
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Diffstat (limited to 'drivers/block/ub.c')
-rw-r--r--drivers/block/ub.c139
1 files changed, 107 insertions, 32 deletions
diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index a05fe5843e6c..f04d864770ad 100644
--- a/drivers/block/ub.c
+++ b/drivers/block/ub.c
@@ -14,7 +14,6 @@
* -- special case some senses, e.g. 3a/0 -> no media present, reduce retries
* -- verify the 13 conditions and do bulk resets
* -- kill last_pipe and simply do two-state clearing on both pipes
- * -- verify protocol (bulk) from USB descriptors (maybe...)
* -- highmem
* -- move top_sense and work_bcs into separate allocations (if they survive)
* for cache purists and esoteric architectures.
@@ -355,7 +354,7 @@ struct ub_lun {
* The USB device instance.
*/
struct ub_dev {
- spinlock_t lock;
+ spinlock_t *lock;
atomic_t poison; /* The USB device is disconnected */
int openc; /* protected by ub_lock! */
/* kref is too implicit for our taste */
@@ -420,11 +419,13 @@ static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
int stalled_pipe);
static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd);
-static void ub_reset_enter(struct ub_dev *sc);
+static void ub_reset_enter(struct ub_dev *sc, int try);
static void ub_reset_task(void *arg);
static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun);
static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
struct ub_capacity *ret);
+static int ub_sync_reset(struct ub_dev *sc);
+static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe);
static int ub_probe_lun(struct ub_dev *sc, int lnum);
/*
@@ -452,6 +453,10 @@ MODULE_DEVICE_TABLE(usb, ub_usb_ids);
#define UB_MAX_HOSTS 26
static char ub_hostv[UB_MAX_HOSTS];
+#define UB_QLOCK_NUM 5
+static spinlock_t ub_qlockv[UB_QLOCK_NUM];
+static int ub_qlock_next = 0;
+
static DEFINE_SPINLOCK(ub_lock); /* Locks globals and ->openc */
/*
@@ -531,7 +536,7 @@ static ssize_t ub_diag_show(struct device *dev, struct device_attribute *attr,
return 0;
cnt = 0;
- spin_lock_irqsave(&sc->lock, flags);
+ spin_lock_irqsave(sc->lock, flags);
cnt += sprintf(page + cnt,
"poison %d reset %d\n",
@@ -579,7 +584,7 @@ static ssize_t ub_diag_show(struct device *dev, struct device_attribute *attr,
if (++nc == SCMD_TRACE_SZ) nc = 0;
}
- spin_unlock_irqrestore(&sc->lock, flags);
+ spin_unlock_irqrestore(sc->lock, flags);
return cnt;
}
@@ -627,6 +632,24 @@ static void ub_id_put(int id)
}
/*
+ * This is necessitated by the fact that blk_cleanup_queue does not
+ * necesserily destroy the queue. Instead, it may merely decrease q->refcnt.
+ * Since our blk_init_queue() passes a spinlock common with ub_dev,
+ * we have life time issues when ub_cleanup frees ub_dev.
+ */
+static spinlock_t *ub_next_lock(void)
+{
+ unsigned long flags;
+ spinlock_t *ret;
+
+ spin_lock_irqsave(&ub_lock, flags);
+ ret = &ub_qlockv[ub_qlock_next];
+ ub_qlock_next = (ub_qlock_next + 1) % UB_QLOCK_NUM;
+ spin_unlock_irqrestore(&ub_lock, flags);
+ return ret;
+}
+
+/*
* Downcount for deallocation. This rides on two assumptions:
* - once something is poisoned, its refcount cannot grow
* - opens cannot happen at this time (del_gendisk was done)
@@ -961,7 +984,7 @@ static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,
if (atomic_read(&sc->poison))
return -ENXIO;
- ub_reset_enter(sc);
+ ub_reset_enter(sc, urq->current_try);
if (urq->current_try >= 3)
return -EIO;
@@ -997,8 +1020,6 @@ static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,
* No exceptions.
*
* Host is assumed locked.
- *
- * XXX We only support Bulk for the moment.
*/
static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
{
@@ -1083,9 +1104,10 @@ static void ub_urb_timeout(unsigned long arg)
struct ub_dev *sc = (struct ub_dev *) arg;
unsigned long flags;
- spin_lock_irqsave(&sc->lock, flags);
- usb_unlink_urb(&sc->work_urb);
- spin_unlock_irqrestore(&sc->lock, flags);
+ spin_lock_irqsave(sc->lock, flags);
+ if (!ub_is_completed(&sc->work_done))
+ usb_unlink_urb(&sc->work_urb);
+ spin_unlock_irqrestore(sc->lock, flags);
}
/*
@@ -1108,10 +1130,9 @@ static void ub_scsi_action(unsigned long _dev)
struct ub_dev *sc = (struct ub_dev *) _dev;
unsigned long flags;
- spin_lock_irqsave(&sc->lock, flags);
- del_timer(&sc->work_timer);
+ spin_lock_irqsave(sc->lock, flags);
ub_scsi_dispatch(sc);
- spin_unlock_irqrestore(&sc->lock, flags);
+ spin_unlock_irqrestore(sc->lock, flags);
}
static void ub_scsi_dispatch(struct ub_dev *sc)
@@ -1133,6 +1154,7 @@ static void ub_scsi_dispatch(struct ub_dev *sc)
} else {
if (!ub_is_completed(&sc->work_done))
break;
+ del_timer(&sc->work_timer);
ub_scsi_urb_compl(sc, cmd);
}
}
@@ -1680,16 +1702,18 @@ static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd)
/*
* Reset management
+ * XXX Move usb_reset_device to khubd. Hogging kevent is not a good thing.
+ * XXX Make usb_sync_reset asynchronous.
*/
-static void ub_reset_enter(struct ub_dev *sc)
+static void ub_reset_enter(struct ub_dev *sc, int try)
{
if (sc->reset) {
/* This happens often on multi-LUN devices. */
return;
}
- sc->reset = 1;
+ sc->reset = try + 1;
#if 0 /* Not needed because the disconnect waits for us. */
unsigned long flags;
@@ -1727,6 +1751,11 @@ static void ub_reset_task(void *arg)
if (atomic_read(&sc->poison)) {
printk(KERN_NOTICE "%s: Not resetting disconnected device\n",
sc->name); /* P3 This floods. Remove soon. XXX */
+ } else if ((sc->reset & 1) == 0) {
+ ub_sync_reset(sc);
+ msleep(700); /* usb-storage sleeps 6s (!) */
+ ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
+ ub_probe_clear_stall(sc, sc->send_bulk_pipe);
} else if (sc->dev->actconfig->desc.bNumInterfaces != 1) {
printk(KERN_NOTICE "%s: Not resetting multi-interface device\n",
sc->name); /* P3 This floods. Remove soon. XXX */
@@ -1754,7 +1783,7 @@ static void ub_reset_task(void *arg)
* queues of resets or anything. We do need a spinlock though,
* to interact with block layer.
*/
- spin_lock_irqsave(&sc->lock, flags);
+ spin_lock_irqsave(sc->lock, flags);
sc->reset = 0;
tasklet_schedule(&sc->tasklet);
list_for_each(p, &sc->luns) {
@@ -1762,7 +1791,7 @@ static void ub_reset_task(void *arg)
blk_start_queue(lun->disk->queue);
}
wake_up(&sc->reset_wait);
- spin_unlock_irqrestore(&sc->lock, flags);
+ spin_unlock_irqrestore(sc->lock, flags);
}
/*
@@ -1990,11 +2019,11 @@ static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun)
cmd->done = ub_probe_done;
cmd->back = &compl;
- spin_lock_irqsave(&sc->lock, flags);
+ spin_lock_irqsave(sc->lock, flags);
cmd->tag = sc->tagcnt++;
rc = ub_submit_scsi(sc, cmd);
- spin_unlock_irqrestore(&sc->lock, flags);
+ spin_unlock_irqrestore(sc->lock, flags);
if (rc != 0) {
printk("ub: testing ready: submit error (%d)\n", rc); /* P3 */
@@ -2052,11 +2081,11 @@ static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
cmd->done = ub_probe_done;
cmd->back = &compl;
- spin_lock_irqsave(&sc->lock, flags);
+ spin_lock_irqsave(sc->lock, flags);
cmd->tag = sc->tagcnt++;
rc = ub_submit_scsi(sc, cmd);
- spin_unlock_irqrestore(&sc->lock, flags);
+ spin_unlock_irqrestore(sc->lock, flags);
if (rc != 0) {
printk("ub: reading capacity: submit error (%d)\n", rc); /* P3 */
@@ -2118,6 +2147,52 @@ static void ub_probe_timeout(unsigned long arg)
}
/*
+ * Reset with a Bulk reset.
+ */
+static int ub_sync_reset(struct ub_dev *sc)
+{
+ int ifnum = sc->intf->cur_altsetting->desc.bInterfaceNumber;
+ struct usb_ctrlrequest *cr;
+ struct completion compl;
+ struct timer_list timer;
+ int rc;
+
+ init_completion(&compl);
+
+ cr = &sc->work_cr;
+ cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
+ cr->bRequest = US_BULK_RESET_REQUEST;
+ cr->wValue = cpu_to_le16(0);
+ cr->wIndex = cpu_to_le16(ifnum);
+ cr->wLength = cpu_to_le16(0);
+
+ usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
+ (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
+ sc->work_urb.actual_length = 0;
+ sc->work_urb.error_count = 0;
+ sc->work_urb.status = 0;
+
+ if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
+ printk(KERN_WARNING
+ "%s: Unable to submit a bulk reset (%d)\n", sc->name, rc);
+ return rc;
+ }
+
+ init_timer(&timer);
+ timer.function = ub_probe_timeout;
+ timer.data = (unsigned long) &compl;
+ timer.expires = jiffies + UB_CTRL_TIMEOUT;
+ add_timer(&timer);
+
+ wait_for_completion(&compl);
+
+ del_timer_sync(&timer);
+ usb_kill_urb(&sc->work_urb);
+
+ return sc->work_urb.status;
+}
+
+/*
* Get number of LUNs by the way of Bulk GetMaxLUN command.
*/
static int ub_sync_getmaxlun(struct ub_dev *sc)
@@ -2333,7 +2408,7 @@ static int ub_probe(struct usb_interface *intf,
if ((sc = kmalloc(sizeof(struct ub_dev), GFP_KERNEL)) == NULL)
goto err_core;
memset(sc, 0, sizeof(struct ub_dev));
- spin_lock_init(&sc->lock);
+ sc->lock = ub_next_lock();
INIT_LIST_HEAD(&sc->luns);
usb_init_urb(&sc->work_urb);
tasklet_init(&sc->tasklet, ub_scsi_action, (unsigned long)sc);
@@ -2483,7 +2558,7 @@ static int ub_probe_lun(struct ub_dev *sc, int lnum)
disk->driverfs_dev = &sc->intf->dev;
rc = -ENOMEM;
- if ((q = blk_init_queue(ub_request_fn, &sc->lock)) == NULL)
+ if ((q = blk_init_queue(ub_request_fn, sc->lock)) == NULL)
goto err_blkqinit;
disk->queue = q;
@@ -2554,7 +2629,7 @@ static void ub_disconnect(struct usb_interface *intf)
* and the whole queue drains. So, we just use this code to
* print warnings.
*/
- spin_lock_irqsave(&sc->lock, flags);
+ spin_lock_irqsave(sc->lock, flags);
{
struct ub_scsi_cmd *cmd;
int cnt = 0;
@@ -2571,7 +2646,7 @@ static void ub_disconnect(struct usb_interface *intf)
"%d was queued after shutdown\n", sc->name, cnt);
}
}
- spin_unlock_irqrestore(&sc->lock, flags);
+ spin_unlock_irqrestore(sc->lock, flags);
/*
* Unregister the upper layer.
@@ -2590,19 +2665,15 @@ static void ub_disconnect(struct usb_interface *intf)
}
/*
- * Taking a lock on a structure which is about to be freed
- * is very nonsensual. Here it is largely a way to do a debug freeze,
- * and a bracket which shows where the nonsensual code segment ends.
- *
* Testing for -EINPROGRESS is always a bug, so we are bending
* the rules a little.
*/
- spin_lock_irqsave(&sc->lock, flags);
+ spin_lock_irqsave(sc->lock, flags);
if (sc->work_urb.status == -EINPROGRESS) { /* janitors: ignore */
printk(KERN_WARNING "%s: "
"URB is active after disconnect\n", sc->name);
}
- spin_unlock_irqrestore(&sc->lock, flags);
+ spin_unlock_irqrestore(sc->lock, flags);
/*
* There is virtually no chance that other CPU runs times so long
@@ -2636,6 +2707,10 @@ static struct usb_driver ub_driver = {
static int __init ub_init(void)
{
int rc;
+ int i;
+
+ for (i = 0; i < UB_QLOCK_NUM; i++)
+ spin_lock_init(&ub_qlockv[i]);
if ((rc = register_blkdev(UB_MAJOR, DRV_NAME)) != 0)
goto err_regblkdev;