[PATCH 09/21] uas: Simplify reset / disconnect handling

Hans de Goede
2014-09-10T11:47:10Z

Drop the whole dance with first moving cmnds to a dead-list. The resetting
flag ensures that no new cmds / urbs will be submitted, and that any urb
completions are short-circuited without trying to complete the scsi cmnd.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
drivers/usb/storage/uas.c | 43 ++++++-------------------------------------
1 file changed, 6 insertions(+), 37 deletions(-)

diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index 4c7d337..bba5498 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -60,7 +60,6 @@ struct uas_dev_info {
spinlock_t lock;
struct work_struct work;
struct list_head inflight_list;
- struct list_head dead_list;
};

enum {
@@ -128,35 +127,6 @@ out:
spin_unlock_irqrestore(&devinfo->lock, flags);
}

-static void uas_mark_cmd_dead(struct uas_dev_info *devinfo,
- struct uas_cmd_info *cmdinfo,
- int result, const char *caller)
-{
- struct scsi_pointer *scp = (void *)cmdinfo;
- struct scsi_cmnd *cmnd = container_of(scp, struct scsi_cmnd, SCp);
-
- uas_log_cmd_state(cmnd, caller);
- lockdep_assert_held(&devinfo->lock);
- WARN_ON_ONCE(cmdinfo->state & COMMAND_ABORTED);
- cmdinfo->state |= COMMAND_ABORTED;
- cmdinfo->state &= ~IS_IN_WORK_LIST;
- cmnd->result = result << 16;
- list_move_tail(&cmdinfo->list, &devinfo->dead_list);
-}
-
-static void uas_abort_inflight(struct uas_dev_info *devinfo, int result,
- const char *caller)
-{
- struct uas_cmd_info *cmdinfo;
- struct uas_cmd_info *temp;
- unsigned long flags;
-
- spin_lock_irqsave(&devinfo->lock, flags);
- list_for_each_entry_safe(cmdinfo, temp, &devinfo->inflight_list, list)
- uas_mark_cmd_dead(devinfo, cmdinfo, result, caller);
- spin_unlock_irqrestore(&devinfo->lock, flags);
-}
-
static void uas_add_work(struct uas_cmd_info *cmdinfo)
{
struct scsi_pointer *scp = (void *)cmdinfo;
@@ -168,7 +138,7 @@ static void uas_add_work(struct uas_cmd_info *cmdinfo)
schedule_work(&devinfo->work);
}

-static void uas_zap_dead(struct uas_dev_info *devinfo)
+static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
{
struct uas_cmd_info *cmdinfo;
struct uas_cmd_info *temp;
@@ -180,11 +150,11 @@ static void uas_zap_dead(struct uas_dev_info *devinfo)
struct scsi_cmnd *cmnd = container_of(scp, struct scsi_cmnd,
SCp);
uas_log_cmd_state(cmnd, __func__);
- WARN_ON_ONCE(!(cmdinfo->state & COMMAND_ABORTED));
/* all urbs are killed, clear inflight bits */
cmdinfo->state &= ~(COMMAND_INFLIGHT |
DATA_IN_URB_INFLIGHT |
DATA_OUT_URB_INFLIGHT);
+ cmnd->result = result << 16;
uas_try_complete(cmnd, __func__);
}
spin_unlock_irqrestore(&devinfo->lock, flags);
@@ -754,11 +724,11 @@ static int uas_eh_bus_reset_handler(struct scsi_cmnd *cmnd)
devinfo->resetting = 1;
spin_unlock_irqrestore(&devinfo->lock, flags);

- uas_abort_inflight(devinfo, DID_RESET, __func__);
usb_kill_anchored_urbs(&devinfo->cmd_urbs);
usb_kill_anchored_urbs(&devinfo->sense_urbs);
usb_kill_anchored_urbs(&devinfo->data_urbs);
- uas_zap_dead(devinfo);
+ uas_zap_pending(devinfo, DID_RESET);
+
err = usb_reset_device(udev);

spin_lock_irqsave(&devinfo->lock, flags);
@@ -935,7 +905,6 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
spin_lock_init(&devinfo->lock);
INIT_WORK(&devinfo->work, uas_do_work);
INIT_LIST_HEAD(&devinfo->inflight_list);
- INIT_LIST_HEAD(&devinfo->dead_list);

result = uas_configure_endpoints(devinfo);
if (result)
@@ -1063,11 +1032,11 @@ static void uas_disconnect(struct usb_interface *intf)
spin_unlock_irqrestore(&devinfo->lock, flags);

cancel_work_sync(&devinfo->work);
- uas_abort_inflight(devinfo, DID_NO_CONNECT, __func__);
usb_kill_anchored_urbs(&devinfo->cmd_urbs);
usb_kill_anchored_urbs(&devinfo->sense_urbs);
usb_kill_anchored_urbs(&devinfo->data_urbs);
- uas_zap_dead(devinfo);
+ uas_zap_pending(devinfo, DID_NO_CONNECT);
+
scsi_remove_host(shost);
uas_free_streams(devinfo);
scsi_host_put(shost);
--
2.1.0