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Commit d8a71dcf authored by Manfred Spraul's avatar Manfred Spraul Committed by Greg Kroah-Hartman
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[PATCH] usb-storage locking fixes 

I found several SMP and UP locking errors in usb-storage, attached is a
patch:

Changes:
* srb->result is a bitfield, several << 1 were missing.
* add scsi_lock calls around midlayer calls, release the lock before
  calling usb functions that might sleep.
* replace the queue semaphore with a queue spinlocks, queuecommand is
  called from bh context.
parent ee73eb81
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Showing with 53 additions and 24 deletions
drivers/usb/storage/datafab.c
View file @ d8a71dcf
......@@ -822,7 +822,7 @@ int datafab_transport(Scsi_Cmnd * srb, struct us_data *us)
srb->result = SUCCESS;
} else {
info->sense_key = UNIT_ATTENTION;
srb->result = CHECK_CONDITION;
srb->result = CHECK_CONDITION << 1;
}
return rc;
}
......
drivers/usb/storage/isd200.c
View file @ d8a71dcf
......@@ -864,7 +864,7 @@ void isd200_invoke_transport( struct us_data *us,
* condition, show that in the result code
*/
if (transferStatus == ISD200_TRANSPORT_FAILED)
srb->result = CHECK_CONDITION;
srb->result = CHECK_CONDITION << 1;
}
#ifdef CONFIG_USB_STORAGE_DEBUG
......
drivers/usb/storage/jumpshot.c
View file @ d8a71dcf
......@@ -821,7 +821,7 @@ int jumpshot_transport(Scsi_Cmnd * srb, struct us_data *us)
srb->result = SUCCESS;
} else {
info->sense_key = UNIT_ATTENTION;
srb->result = CHECK_CONDITION;
srb->result = CHECK_CONDITION << 1;
}
return rc;
}
......
drivers/usb/storage/scsiglue.c
View file @ d8a71dcf
......@@ -70,7 +70,11 @@ static const char* host_info(struct Scsi_Host *host)
return "SCSI emulation for USB Mass Storage devices";
}
/* detect a virtual adapter (always works) */
/* detect a virtual adapter (always works)
* Synchronization: 2.4: with the io_request_lock
* 2.5: no locks.
* fortunately we don't care.
* */
static int detect(struct SHT *sht)
{
struct us_data *us;
......@@ -82,7 +86,7 @@ static int detect(struct SHT *sht)
/* set up the name of our subdirectory under /proc/scsi/ */
sprintf(local_name, "usb-storage-%d", us->host_number);
sht->proc_name = kmalloc (strlen(local_name) + 1, GFP_KERNEL);
sht->proc_name = kmalloc (strlen(local_name) + 1, GFP_ATOMIC);
if (!sht->proc_name)
return 0;
strcpy(sht->proc_name, local_name);
......@@ -108,6 +112,7 @@ static int detect(struct SHT *sht)
*
* NOTE: There is no contention here, because we're already deregistered
* the driver and we're doing each virtual host in turn, not in parallel
* Synchronization: BLK, no spinlock.
*/
static int release(struct Scsi_Host *psh)
{
......@@ -145,12 +150,13 @@ static int command( Scsi_Cmnd *srb )
static int queuecommand( Scsi_Cmnd *srb , void (*done)(Scsi_Cmnd *))
{
struct us_data *us = (struct us_data *)srb->host->hostdata[0];
unsigned long flags;
US_DEBUGP("queuecommand() called\n");
srb->host_scribble = (unsigned char *)us;
/* get exclusive access to the structures we want */
down(&(us->queue_exclusion));
spin_lock_irqsave(&us->queue_exclusion, flags);
/* enqueue the command */
us->queue_srb = srb;
......@@ -158,7 +164,7 @@ static int queuecommand( Scsi_Cmnd *srb , void (*done)(Scsi_Cmnd *))
us->action = US_ACT_COMMAND;
/* release the lock on the structure */
up(&(us->queue_exclusion));
spin_unlock_irqrestore(&us->queue_exclusion, flags);
/* wake up the process task */
up(&(us->sema));
......@@ -178,10 +184,12 @@ static int command_abort( Scsi_Cmnd *srb )
US_DEBUGP("command_abort() called\n");
if (atomic_read(&us->sm_state) == US_STATE_RUNNING) {
scsi_unlock(srb->host);
usb_stor_abort_transport(us);
/* wait for us to be done */
wait_for_completion(&(us->notify));
scsi_lock(srb->host);
return SUCCESS;
}
......@@ -202,6 +210,7 @@ static int device_reset( Scsi_Cmnd *srb )
if (atomic_read(&us->sm_state) == US_STATE_DETACHED)
return SUCCESS;
scsi_unlock(srb->host);
/* lock the device pointers */
down(&(us->dev_semaphore));
us->srb = srb;
......@@ -211,6 +220,7 @@ static int device_reset( Scsi_Cmnd *srb )
/* unlock the device pointers */
up(&(us->dev_semaphore));
scsi_lock(srb->host);
return result;
}
......@@ -234,10 +244,13 @@ static int bus_reset( Scsi_Cmnd *srb )
}
/* attempt to reset the port */
scsi_unlock(srb->host);
result = usb_reset_device(pusb_dev_save);
US_DEBUGP("usb_reset_device returns %d\n", result);
if (result < 0)
if (result < 0) {
scsi_lock(srb->host);
return FAILED;
}
/* FIXME: This needs to lock out driver probing while it's working
* or we can have race conditions */
......@@ -262,8 +275,8 @@ static int bus_reset( Scsi_Cmnd *srb )
intf->driver->probe(pusb_dev_save, i, id);
up(&intf->driver->serialize);
}
US_DEBUGP("bus_reset() complete\n");
scsi_lock(srb->host);
return SUCCESS;
}
......@@ -271,6 +284,7 @@ static int bus_reset( Scsi_Cmnd *srb )
static int host_reset( Scsi_Cmnd *srb )
{
printk(KERN_CRIT "usb-storage: host_reset() requested but not implemented\n" );
bus_reset(srb);
return FAILED;
}
......
drivers/usb/storage/usb.c
View file @ d8a71dcf
......@@ -337,9 +337,9 @@ static int usb_stor_control_thread(void * __us)
/* signal that we've started the thread */
complete(&(us->notify));
set_current_state(TASK_INTERRUPTIBLE);
for(;;) {
struct Scsi_Host *host;
US_DEBUGP("*** thread sleeping.\n");
if(down_interruptible(&us->sema))
break;
......@@ -347,15 +347,16 @@ static int usb_stor_control_thread(void * __us)
US_DEBUGP("*** thread awakened.\n");
/* lock access to the queue element */
down(&(us->queue_exclusion));
spin_lock_irq(&us->queue_exclusion);
/* take the command off the queue */
action = us->action;
us->action = 0;
us->srb = us->queue_srb;
host = us->srb->host;
/* release the queue lock as fast as possible */
up(&(us->queue_exclusion));
spin_unlock_irq(&us->queue_exclusion);
switch (action) {
case US_ACT_COMMAND:
......@@ -365,9 +366,10 @@ static int usb_stor_control_thread(void * __us)
if (us->srb->sc_data_direction == SCSI_DATA_UNKNOWN) {
US_DEBUGP("UNKNOWN data direction\n");
us->srb->result = DID_ERROR << 16;
set_current_state(TASK_INTERRUPTIBLE);
scsi_lock(host);
us->srb->scsi_done(us->srb);
us->srb = NULL;
scsi_unlock(host);
break;
}
......@@ -380,9 +382,10 @@ static int usb_stor_control_thread(void * __us)
us->srb->target, us->srb->lun);
us->srb->result = DID_BAD_TARGET << 16;
set_current_state(TASK_INTERRUPTIBLE);
scsi_lock(host);
us->srb->scsi_done(us->srb);
us->srb = NULL;
scsi_unlock(host);
break;
}
......@@ -391,9 +394,10 @@ static int usb_stor_control_thread(void * __us)
us->srb->target, us->srb->lun);
us->srb->result = DID_BAD_TARGET << 16;
set_current_state(TASK_INTERRUPTIBLE);
scsi_lock(host);
us->srb->scsi_done(us->srb);
us->srb = NULL;
scsi_unlock(host);
break;
}
......@@ -403,9 +407,10 @@ static int usb_stor_control_thread(void * __us)
US_DEBUGP("Skipping START_STOP command\n");
us->srb->result = GOOD << 1;
set_current_state(TASK_INTERRUPTIBLE);
scsi_lock(host);
us->srb->scsi_done(us->srb);
us->srb = NULL;
scsi_unlock(host);
break;
}
......@@ -466,14 +471,15 @@ static int usb_stor_control_thread(void * __us)
if (us->srb->result != DID_ABORT << 16) {
US_DEBUGP("scsi cmd done, result=0x%x\n",
us->srb->result);
set_current_state(TASK_INTERRUPTIBLE);
scsi_lock(host);
us->srb->scsi_done(us->srb);
us->srb = NULL;
scsi_unlock(host);
} else {
US_DEBUGP("scsi command aborted\n");
set_current_state(TASK_INTERRUPTIBLE);
us->srb = NULL;
complete(&(us->notify));
}
us->srb = NULL;
break;
case US_ACT_DEVICE_RESET:
......@@ -494,9 +500,6 @@ static int usb_stor_control_thread(void * __us)
}
} /* for (;;) */
/* clean up after ourselves */
set_current_state(TASK_INTERRUPTIBLE);
/* notify the exit routine that we're actually exiting now */
complete(&(us->notify));
......@@ -773,7 +776,7 @@ static void * storage_probe(struct usb_device *dev, unsigned int ifnum,
/* Initialize the mutexes only when the struct is new */
init_completion(&(ss->notify));
init_MUTEX_LOCKED(&(ss->ip_waitq));
init_MUTEX(&(ss->queue_exclusion));
spin_lock_init(&ss->queue_exclusion);
init_MUTEX(&(ss->irq_urb_sem));
init_MUTEX(&(ss->current_urb_sem));
init_MUTEX(&(ss->dev_semaphore));
......
drivers/usb/storage/usb.h
View file @ d8a71dcf
......@@ -180,7 +180,7 @@ struct us_data {
/* mutual exclusion structures */
struct completion notify; /* thread begin/end */
struct semaphore queue_exclusion; /* to protect data structs */
spinlock_t queue_exclusion; /* to protect data structs */
struct us_unusual_dev *unusual_dev; /* If unusual device */
void *extra; /* Any extra data */
extra_data_destructor extra_destructor;/* extra data destructor */
......@@ -197,4 +197,16 @@ extern struct usb_driver usb_storage_driver;
extern void fill_inquiry_response(struct us_data *us,
unsigned char *data, unsigned int data_len);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,3)
#define scsi_unlock(host) spin_unlock_irq(host->host_lock)
#define scsi_lock(host) spin_lock_irq(host->host_lock)
#define sg_address(psg) (page_address((psg)->page) + (psg)->offset)
#else
#define scsi_unlock(host) spin_unlock_irq(&io_request_lock)
#define scsi_lock(host) spin_lock_irq(&io_request_lock)
#define sg_address(psg) ((psg)->address)
#endif
#endif
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