[PATCH v2 5/5] uas: add locking
Add spinlock to protect uas data structures.
[ v2: s/GFP_NOIO/GFP_ATOMIC/, better don't sleep when holding a spinlock ]
Signed-off-by: Gerd Hoffmann
---
drivers/usb/storage/uas.c | 51 ++--
1 files changed, 44 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index df1d72e..1578909 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -50,6 +50,7 @@ struct uas_dev_info {
unsigned use_streams:1;
unsigned uas_sense_old:1;
struct scsi_cmnd *cmnd;
+ spinlock_t lock;
};
enum {
@@ -91,6 +92,7 @@ static void uas_do_work(struct work_struct *work)
struct uas_cmd_info *cmdinfo;
struct uas_cmd_info *temp;
struct list_head list;
+ unsigned long flags;
int err;
spin_lock_irq(&uas_work_lock);
@@ -101,7 +103,10 @@ static void uas_do_work(struct work_struct *work)
struct scsi_pointer *scp = (void *)cmdinfo;
struct scsi_cmnd *cmnd = container_of(scp,
struct scsi_cmnd, SCp);
- err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_NOIO);
+ struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
+ spin_lock_irqsave(&devinfo->lock, flags);
+ err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_ATOMIC);
+ spin_unlock_irqrestore(&devinfo->lock, flags);
if (err) {
list_del(&cmdinfo->list);
spin_lock_irq(&uas_work_lock);
@@ -182,7 +187,9 @@ static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const
char *caller)
static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
{
struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+ struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
+ WARN_ON(!spin_is_locked(&devinfo->lock));
if (cmdinfo->state & (COMMAND_INFLIGHT |
DATA_IN_URB_INFLIGHT |
DATA_OUT_URB_INFLIGHT))
@@ -222,6 +229,7 @@ static void uas_stat_cmplt(struct urb *urb)
struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
struct scsi_cmnd *cmnd;
struct uas_cmd_info *cmdinfo;
+ unsigned long flags;
u16 tag;
if (urb->status) {
@@ -235,6 +243,7 @@ static void uas_stat_cmplt(struct urb *urb)
return;
}
+ spin_lock_irqsave(&devinfo->lock, flags);
tag = be16_to_cpup(&iu->tag) - 1;
if (tag == 0)
cmnd = devinfo->cmnd;
@@ -243,6 +252,7 @@ static void uas_stat_cmplt(struct urb *urb)
if (!cmnd) {
if (iu->iu_id != IU_ID_RESPONSE) {
usb_free_urb(urb);
+ spin_unlock_irqrestore(&devinfo->lock, flags);
return;
}
} else {
@@ -262,10 +272,16 @@ static void uas_stat_cmplt(struct urb *urb)
uas_sense(urb, cmnd);
if (cmnd->result != 0) {
/* cancel data transfers on error */
- if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
+ if (cmdinfo->state & DATA_IN_URB_INFLIGHT) {
+ spin_unlock_irqrestore(&devinfo->lock, flags);
usb_unlink_urb(cmdinfo->data_in_urb);
- if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
+ spin_lock_irqsave(&devinfo->lock, flags);
+ }
+ if (cmdinfo->state & DATA_OUT_URB_INFLIGHT) {
+ spin_unlock_irqrestore(&devinfo->lock, flags);
usb_unlink_urb(cmdinfo->data_out_urb);
+ spin_lock_irqsave(&devinfo->lock, flags);
+ }
}
cmdinfo->state &= ~COMMAND_INFLIGHT;
uas_try_complete(cmnd, __func__);
@@ -285,14 +301,18 @@ static void uas_stat_cmplt(struct urb *urb)
"Bogus IU (%d) received on status pipe\n", iu->iu_id);
}
usb_free_urb(urb);
+ spin_unlock_irqrestore(&devinfo->lock, flags);
}
static void uas_data_cmplt(struct urb *urb)
{
struct scsi_cmnd *cmnd = urb->context;
struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+ struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
struct scsi_data_buffer *sdb = NULL;
+ unsigned long flags;
+ spin_lock_irqsave(&devinfo->lock, flags);
if (cmdinfo->data_in_urb == urb) {
sdb = scsi_in(cmnd);
cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
@@ -308,6 +328,7 @@ static void uas_data_cmplt(struct urb *urb)
sdb->resid = sdb->length - urb->actual_length;
}
uas_try_complete
[PATCH v2 5/5] uas: add locking
Add spinlock to protect uas data structures.
[ v2: s/GFP_NOIO/GFP_ATOMIC/, better don't sleep when holding a spinlock ]
Signed-off-by: Gerd Hoffmann
---
drivers/usb/storage/uas.c | 51 ++--
1 files changed, 44 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index df1d72e..1578909 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -50,6 +50,7 @@ struct uas_dev_info {
unsigned use_streams:1;
unsigned uas_sense_old:1;
struct scsi_cmnd *cmnd;
+ spinlock_t lock;
};
enum {
@@ -91,6 +92,7 @@ static void uas_do_work(struct work_struct *work)
struct uas_cmd_info *cmdinfo;
struct uas_cmd_info *temp;
struct list_head list;
+ unsigned long flags;
int err;
spin_lock_irq(&uas_work_lock);
@@ -101,7 +103,10 @@ static void uas_do_work(struct work_struct *work)
struct scsi_pointer *scp = (void *)cmdinfo;
struct scsi_cmnd *cmnd = container_of(scp,
struct scsi_cmnd, SCp);
- err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_NOIO);
+ struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
+ spin_lock_irqsave(&devinfo->lock, flags);
+ err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_ATOMIC);
+ spin_unlock_irqrestore(&devinfo->lock, flags);
if (err) {
list_del(&cmdinfo->list);
spin_lock_irq(&uas_work_lock);
@@ -182,7 +187,9 @@ static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const
char *caller)
static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
{
struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+ struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
+ WARN_ON(!spin_is_locked(&devinfo->lock));
if (cmdinfo->state & (COMMAND_INFLIGHT |
DATA_IN_URB_INFLIGHT |
DATA_OUT_URB_INFLIGHT))
@@ -222,6 +229,7 @@ static void uas_stat_cmplt(struct urb *urb)
struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
struct scsi_cmnd *cmnd;
struct uas_cmd_info *cmdinfo;
+ unsigned long flags;
u16 tag;
if (urb->status) {
@@ -235,6 +243,7 @@ static void uas_stat_cmplt(struct urb *urb)
return;
}
+ spin_lock_irqsave(&devinfo->lock, flags);
tag = be16_to_cpup(&iu->tag) - 1;
if (tag == 0)
cmnd = devinfo->cmnd;
@@ -243,6 +252,7 @@ static void uas_stat_cmplt(struct urb *urb)
if (!cmnd) {
if (iu->iu_id != IU_ID_RESPONSE) {
usb_free_urb(urb);
+ spin_unlock_irqrestore(&devinfo->lock, flags);
return;
}
} else {
@@ -262,10 +272,16 @@ static void uas_stat_cmplt(struct urb *urb)
uas_sense(urb, cmnd);
if (cmnd->result != 0) {
/* cancel data transfers on error */
- if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
+ if (cmdinfo->state & DATA_IN_URB_INFLIGHT) {
+ spin_unlock_irqrestore(&devinfo->lock, flags);
usb_unlink_urb(cmdinfo->data_in_urb);
- if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
+ spin_lock_irqsave(&devinfo->lock, flags);
+ }
+ if (cmdinfo->state & DATA_OUT_URB_INFLIGHT) {
+ spin_unlock_irqrestore(&devinfo->lock, flags);
usb_unlink_urb(cmdinfo->data_out_urb);
+ spin_lock_irqsave(&devinfo->lock, flags);
+ }
}
cmdinfo->state &= ~COMMAND_INFLIGHT;
uas_try_complete(cmnd, __func__);
@@ -285,14 +301,18 @@ static void uas_stat_cmplt(struct urb *urb)
"Bogus IU (%d) received on status pipe\n", iu->iu_id);
}
usb_free_urb(urb);
+ spin_unlock_irqrestore(&devinfo->lock, flags);
}
static void uas_data_cmplt(struct urb *urb)
{
struct scsi_cmnd *cmnd = urb->context;
struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+ struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
struct scsi_data_buffer *sdb = NULL;
+ unsigned long flags;
+ spin_lock_irqsave(&devinfo->lock, flags);
if (cmdinfo->data_in_urb == urb) {
sdb = scsi_in(cmnd);
cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
@@ -308,6 +328,7 @@ static void uas_data_cmplt(struct urb *urb)
sdb->resid = sdb->length - urb->actual_length;
}
uas_try_complete
