[S390] subchannel lock conversion.

Convert the subchannel lock to a pointer to a lock.  Needed for the dynamic
subchannel mapping patch.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

6 files changed, 98 insertions, 63 deletions

diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index dbfb77b03928..cbab8d2ce5cf 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -183,7 +183,7 @@ css_get_ssd_info(struct subchannel *sch)
         page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
         if (!page)
                 return -ENOMEM;
-        spin_lock_irq(&sch->lock);
+        spin_lock_irq(sch->lock);
         ret = chsc_get_sch_desc_irq(sch, page);
         if (ret) {
                 static int cio_chsc_err_msg;
@@ -197,7 +197,7 @@ css_get_ssd_info(struct subchannel *sch)
                         cio_chsc_err_msg = 1;
                 }
         }
-        spin_unlock_irq(&sch->lock);
+        spin_unlock_irq(sch->lock);
         free_page((unsigned long)page);
         if (!ret) {
                 int j, chpid, mask;
@@ -233,7 +233,7 @@ s390_subchannel_remove_chpid(struct device *dev, void *data)
         if (j >= 8)
                 return 0;
 
-        spin_lock_irq(&sch->lock);
+        spin_lock_irq(sch->lock);
 
         stsch(sch->schid, &schib);
         if (!schib.pmcw.dnv)
@@ -265,10 +265,10 @@ s390_subchannel_remove_chpid(struct device *dev, void *data)
         else if (sch->lpm == mask)
                 goto out_unreg;
 out_unlock:
-        spin_unlock_irq(&sch->lock);
+        spin_unlock_irq(sch->lock);
         return 0;
 out_unreg:
-        spin_unlock_irq(&sch->lock);
+        spin_unlock_irq(sch->lock);
         sch->lpm = 0;
         if (css_enqueue_subchannel_slow(sch->schid)) {
                 css_clear_subchannel_slow_list();
@@ -378,12 +378,12 @@ __s390_process_res_acc(struct subchannel_id schid, void *data)
                 /* Check if a subchannel is newly available. */
                 return s390_process_res_acc_new_sch(schid);
 
-        spin_lock_irq(&sch->lock);
+        spin_lock_irq(sch->lock);
 
         chp_mask = s390_process_res_acc_sch(res_data, sch);
 
         if (chp_mask == 0) {
-                spin_unlock_irq(&sch->lock);
+                spin_unlock_irq(sch->lock);
                 put_device(&sch->dev);
                 return 0;
         }
@@ -397,7 +397,7 @@ __s390_process_res_acc(struct subchannel_id schid, void *data)
         else if (sch->driver && sch->driver->verify)
                 sch->driver->verify(&sch->dev);
 
-        spin_unlock_irq(&sch->lock);
+        spin_unlock_irq(sch->lock);
         put_device(&sch->dev);
         return 0;
 }
@@ -635,21 +635,21 @@ __chp_add(struct subchannel_id schid, void *data)
         if (!sch)
                 /* Check if the subchannel is now available. */
                 return __chp_add_new_sch(schid);
-        spin_lock_irq(&sch->lock);
+        spin_lock_irq(sch->lock);
         for (i=0; i<8; i++) {
                 mask = 0x80 >> i;
                 if ((sch->schib.pmcw.pim & mask) &&
                     (sch->schib.pmcw.chpid[i] == chp->id)) {
                         if (stsch(sch->schid, &sch->schib) != 0) {
                                 /* Endgame. */
-                                spin_unlock_irq(&sch->lock);
+                                spin_unlock_irq(sch->lock);
                                 return -ENXIO;
                         }
                         break;
                 }
         }
         if (i==8) {
-                spin_unlock_irq(&sch->lock);
+                spin_unlock_irq(sch->lock);
                 return 0;
         }
         sch->lpm = ((sch->schib.pmcw.pim &
@@ -660,7 +660,7 @@ __chp_add(struct subchannel_id schid, void *data)
         if (sch->driver && sch->driver->verify)
                 sch->driver->verify(&sch->dev);
 
-        spin_unlock_irq(&sch->lock);
+        spin_unlock_irq(sch->lock);
         put_device(&sch->dev);
         return 0;
 }
@@ -750,7 +750,7 @@ __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
         if (!sch->ssd_info.valid)
                 return;
         
-        spin_lock_irqsave(&sch->lock, flags);
+        spin_lock_irqsave(sch->lock, flags);
         old_lpm = sch->lpm;
         for (chp = 0; chp < 8; chp++) {
                 if (sch->ssd_info.chpid[chp] != chpid)
@@ -785,7 +785,7 @@ __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
                         sch->driver->verify(&sch->dev);
                 break;
         }
-        spin_unlock_irqrestore(&sch->lock, flags);
+        spin_unlock_irqrestore(sch->lock, flags);
 }
 
 static int
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 20aee2783847..e8d331493fd8 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -143,11 +143,11 @@ cio_tpi(void)
                 return 1;
         local_bh_disable();
         irq_enter ();
-        spin_lock(&sch->lock);
+        spin_lock(sch->lock);
         memcpy (&sch->schib.scsw, &irb->scsw, sizeof (struct scsw));
         if (sch->driver && sch->driver->irq)
                 sch->driver->irq(&sch->dev);
-        spin_unlock(&sch->lock);
+        spin_unlock(sch->lock);
         irq_exit ();
         _local_bh_enable();
         return 1;
@@ -496,6 +496,15 @@ cio_disable_subchannel (struct subchannel *sch)
         return ret;
 }
 
+static int cio_create_sch_lock(struct subchannel *sch)
+{
+        sch->lock = kmalloc(sizeof(spinlock_t), GFP_KERNEL);
+        if (!sch->lock)
+                return -ENOMEM;
+        spin_lock_init(sch->lock);
+        return 0;
+}
+
 /*
  * cio_validate_subchannel()
  *
@@ -513,6 +522,7 @@ cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
 {
         char dbf_txt[15];
         int ccode;
+        int err;
 
         sprintf (dbf_txt, "valsch%x", schid.sch_no);
         CIO_TRACE_EVENT (4, dbf_txt);
@@ -520,9 +530,15 @@ cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
         /* Nuke all fields. */
         memset(sch, 0, sizeof(struct subchannel));
 
-        spin_lock_init(&sch->lock);
+        sch->schid = schid;
+        if (cio_is_console(schid)) {
+                sch->lock = cio_get_console_lock();
+        } else {
+                err = cio_create_sch_lock(sch);
+                if (err)
+                        goto out;
+        }
         mutex_init(&sch->reg_mutex);
-
         /* Set a name for the subchannel */
         snprintf (sch->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x", schid.ssid,
                   schid.sch_no);
@@ -534,10 +550,10 @@ cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
          *  is not valid.
          */
         ccode = stsch_err (schid, &sch->schib);
-        if (ccode)
-                return (ccode == 3) ? -ENXIO : ccode;
-
-        sch->schid = schid;
+        if (ccode) {
+                err = (ccode == 3) ? -ENXIO : ccode;
+                goto out;
+        }
         /* Copy subchannel type from path management control word. */
         sch->st = sch->schib.pmcw.st;
 
@@ -550,14 +566,16 @@ cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
                           "non-I/O subchannel type %04X\n",
                           sch->schid.ssid, sch->schid.sch_no, sch->st);
                 /* We stop here for non-io subchannels. */
-                return sch->st;
+                err = sch->st;
+                goto out;
         }
 
         /* Initialization for io subchannels. */
-        if (!sch->schib.pmcw.dnv)
+        if (!sch->schib.pmcw.dnv) {
                 /* io subchannel but device number is invalid. */
-                return -ENODEV;
-
+                err = -ENODEV;
+                goto out;
+        }
         /* Devno is valid. */
         if (is_blacklisted (sch->schid.ssid, sch->schib.pmcw.dev)) {
                 /*
@@ -567,7 +585,8 @@ cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
                 CIO_MSG_EVENT(0, "Blacklisted device detected "
                               "at devno %04X, subchannel set %x\n",
                               sch->schib.pmcw.dev, sch->schid.ssid);
-                return -ENODEV;
+                err = -ENODEV;
+                goto out;
         }
         sch->opm = 0xff;
         if (!cio_is_console(sch->schid))
@@ -595,6 +614,11 @@ cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
         if ((sch->lpm & (sch->lpm - 1)) != 0)
                 sch->schib.pmcw.mp = 1; /* multipath mode */
         return 0;
+out:
+        if (!cio_is_console(schid))
+                kfree(sch->lock);
+        sch->lock = NULL;
+        return err;
 }
 
 /*
@@ -637,7 +661,7 @@ do_IRQ (struct pt_regs *regs)
                 }
                 sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
                 if (sch)
-                        spin_lock(&sch->lock);
+                        spin_lock(sch->lock);
                 /* Store interrupt response block to lowcore. */
                 if (tsch (tpi_info->schid, irb) == 0 && sch) {
                         /* Keep subchannel information word up to date. */
@@ -648,7 +672,7 @@ do_IRQ (struct pt_regs *regs)
                                 sch->driver->irq(&sch->dev);
                 }
                 if (sch)
-                        spin_unlock(&sch->lock);
+                        spin_unlock(sch->lock);
                 /*
                  * Are more interrupts pending?
                  * If so, the tpi instruction will update the lowcore
@@ -687,10 +711,10 @@ wait_cons_dev (void)
         __ctl_load (cr6, 6, 6);
 
         do {
-                spin_unlock(&console_subchannel.lock);
+                spin_unlock(console_subchannel.lock);
                 if (!cio_tpi())
                         cpu_relax();
-                spin_lock(&console_subchannel.lock);
+                spin_lock(console_subchannel.lock);
         } while (console_subchannel.schib.scsw.actl != 0);
         /*
          * restore previous isc value
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index 4541c1af4b66..7e7369b21a93 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -87,7 +87,7 @@ struct orb {
 /* subchannel data structure used by I/O subroutines */
 struct subchannel {
         struct subchannel_id schid;
-        spinlock_t lock;        /* subchannel lock */
+        spinlock_t *lock;       /* subchannel lock */
         struct mutex reg_mutex;
         enum {
                 SUBCHANNEL_TYPE_IO = 0,
@@ -137,9 +137,11 @@ extern struct subchannel *cio_probe_console(void);
 extern void cio_release_console(void);
 extern int cio_is_console(struct subchannel_id);
 extern struct subchannel *cio_get_console_subchannel(void);
+extern spinlock_t * cio_get_console_lock(void);
 #else
 #define cio_is_console(schid) 0
 #define cio_get_console_subchannel() NULL
+#define cio_get_console_lock() NULL;
 #endif
 
 extern int cio_show_msg;
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 55895c83d499..65939e2eb415 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -91,9 +91,9 @@ css_free_subchannel(struct subchannel *sch)
                 /* Reset intparm to zeroes. */
                 sch->schib.pmcw.intparm = 0;
                 cio_modify(sch);
+                kfree(sch->lock);
                 kfree(sch);
         }
-        
 }
 
 static void
@@ -102,8 +102,10 @@ css_subchannel_release(struct device *dev)
         struct subchannel *sch;
 
         sch = to_subchannel(dev);
-        if (!cio_is_console(sch->schid))
+        if (!cio_is_console(sch->schid)) {
+                kfree(sch->lock);
                 kfree(sch);
+        }
 }
 
 extern int css_get_ssd_info(struct subchannel *sch);
@@ -206,18 +208,18 @@ static int css_evaluate_known_subchannel(struct subchannel *sch, int slow)
         unsigned long flags;
         enum { NONE, UNREGISTER, UNREGISTER_PROBE, REPROBE } action;
 
-        spin_lock_irqsave(&sch->lock, flags);
+        spin_lock_irqsave(sch->lock, flags);
         disc = device_is_disconnected(sch);
         if (disc && slow) {
                 /* Disconnected devices are evaluated directly only.*/
-                spin_unlock_irqrestore(&sch->lock, flags);
+                spin_unlock_irqrestore(sch->lock, flags);
                 return 0;
         }
         /* No interrupt after machine check - kill pending timers. */
         device_kill_pending_timer(sch);
         if (!disc && !slow) {
                 /* Non-disconnected devices are evaluated on the slow path. */
-                spin_unlock_irqrestore(&sch->lock, flags);
+                spin_unlock_irqrestore(sch->lock, flags);
                 return -EAGAIN;
         }
         event = css_get_subchannel_status(sch);
@@ -242,9 +244,9 @@ static int css_evaluate_known_subchannel(struct subchannel *sch, int slow)
                 /* Ask driver what to do with device. */
                 action = UNREGISTER;
                 if (sch->driver && sch->driver->notify) {
-                        spin_unlock_irqrestore(&sch->lock, flags);
+                        spin_unlock_irqrestore(sch->lock, flags);
                         ret = sch->driver->notify(&sch->dev, event);
-                        spin_lock_irqsave(&sch->lock, flags);
+                        spin_lock_irqsave(sch->lock, flags);
                         if (ret)
                                 action = NONE;
                 }
@@ -269,9 +271,9 @@ static int css_evaluate_known_subchannel(struct subchannel *sch, int slow)
         case UNREGISTER:
         case UNREGISTER_PROBE:
                 /* Unregister device (will use subchannel lock). */
-                spin_unlock_irqrestore(&sch->lock, flags);
+                spin_unlock_irqrestore(sch->lock, flags);
                 css_sch_device_unregister(sch);
-                spin_lock_irqsave(&sch->lock, flags);
+                spin_lock_irqsave(sch->lock, flags);
 
                 /* Reset intparm to zeroes. */
                 sch->schib.pmcw.intparm = 0;
@@ -283,7 +285,7 @@ static int css_evaluate_known_subchannel(struct subchannel *sch, int slow)
         default:
                 break;
         }
-        spin_unlock_irqrestore(&sch->lock, flags);
+        spin_unlock_irqrestore(sch->lock, flags);
         /* Probe if necessary. */
         if (action == UNREGISTER_PROBE)
                 ret = css_probe_device(sch->schid);
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index e644fd6905ee..9a31239fe028 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -774,9 +774,9 @@ io_subchannel_register(struct work_struct *work)
                 printk (KERN_WARNING "%s: could not register %s\n",
                         __func__, cdev->dev.bus_id);
                 put_device(&cdev->dev);
-                spin_lock_irqsave(&sch->lock, flags);
+                spin_lock_irqsave(sch->lock, flags);
                 sch->dev.driver_data = NULL;
-                spin_unlock_irqrestore(&sch->lock, flags);
+                spin_unlock_irqrestore(sch->lock, flags);
                 kfree (cdev->private);
                 kfree (cdev);
                 put_device(&sch->dev);
@@ -860,7 +860,7 @@ io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 
         sch->dev.driver_data = cdev;
         sch->driver = &io_subchannel_driver;
-        cdev->ccwlock = &sch->lock;
+        cdev->ccwlock = sch->lock;
 
         /* Init private data. */
         priv = cdev->private;
@@ -880,9 +880,9 @@ io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
         atomic_inc(&ccw_device_init_count);
 
         /* Start async. device sensing. */
-        spin_lock_irq(&sch->lock);
+        spin_lock_irq(sch->lock);
         rc = ccw_device_recognition(cdev);
-        spin_unlock_irq(&sch->lock);
+        spin_unlock_irq(sch->lock);
         if (rc) {
                 if (atomic_dec_and_test(&ccw_device_init_count))
                         wake_up(&ccw_device_init_wq);
@@ -924,9 +924,9 @@ io_subchannel_probe (struct subchannel *sch)
 
         rc = io_subchannel_recog(cdev, sch);
         if (rc) {
-                spin_lock_irqsave(&sch->lock, flags);
+                spin_lock_irqsave(sch->lock, flags);
                 sch->dev.driver_data = NULL;
-                spin_unlock_irqrestore(&sch->lock, flags);
+                spin_unlock_irqrestore(sch->lock, flags);
                 if (cdev->dev.release)
                         cdev->dev.release(&cdev->dev);
         }
@@ -1036,6 +1036,13 @@ static struct ccw_device console_cdev;
 static struct ccw_device_private console_private;
 static int console_cdev_in_use;
 
+static DEFINE_SPINLOCK(ccw_console_lock);
+
+spinlock_t * cio_get_console_lock(void)
+{
+        return &ccw_console_lock;
+}
+
 static int
 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
 {
diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
index b39c1fa48acd..d269607336ec 100644
--- a/drivers/s390/cio/device_ops.c
+++ b/drivers/s390/cio/device_ops.c
@@ -316,9 +316,9 @@ __ccw_device_retry_loop(struct ccw_device *cdev, struct ccw1 *ccw, long magic, _
                         ccw_device_set_timeout(cdev, 0);
                 if (ret == -EBUSY) {
                         /* Try again later. */
-                        spin_unlock_irq(&sch->lock);
+                        spin_unlock_irq(sch->lock);
                         msleep(10);
-                        spin_lock_irq(&sch->lock);
+                        spin_lock_irq(sch->lock);
                         continue;
                 }
                 if (ret != 0)
@@ -326,12 +326,12 @@ __ccw_device_retry_loop(struct ccw_device *cdev, struct ccw1 *ccw, long magic, _
                         break;
                 /* Wait for end of request. */
                 cdev->private->intparm = magic;
-                spin_unlock_irq(&sch->lock);
+                spin_unlock_irq(sch->lock);
                 wait_event(cdev->private->wait_q,
                            (cdev->private->intparm == -EIO) ||
                            (cdev->private->intparm == -EAGAIN) ||
                            (cdev->private->intparm == 0));
-                spin_lock_irq(&sch->lock);
+                spin_lock_irq(sch->lock);
                 /* Check at least for channel end / device end */
                 if (cdev->private->intparm == -EIO) {
                         /* Non-retryable error. */
@@ -342,9 +342,9 @@ __ccw_device_retry_loop(struct ccw_device *cdev, struct ccw1 *ccw, long magic, _
                         /* Success. */
                         break;
                 /* Try again later. */
-                spin_unlock_irq(&sch->lock);
+                spin_unlock_irq(sch->lock);
                 msleep(10);
-                spin_lock_irq(&sch->lock);
+                spin_lock_irq(sch->lock);
         } while (1);
 
         return ret;
@@ -389,7 +389,7 @@ read_dev_chars (struct ccw_device *cdev, void **buffer, int length)
                 return ret;
         }
 
-        spin_lock_irq(&sch->lock);
+        spin_lock_irq(sch->lock);
         /* Save interrupt handler. */
         handler = cdev->handler;
         /* Temporarily install own handler. */
@@ -406,7 +406,7 @@ read_dev_chars (struct ccw_device *cdev, void **buffer, int length)
 
         /* Restore interrupt handler. */
         cdev->handler = handler;
-        spin_unlock_irq(&sch->lock);
+        spin_unlock_irq(sch->lock);
 
         clear_normalized_cda (rdc_ccw);
         kfree(rdc_ccw);
@@ -463,7 +463,7 @@ read_conf_data_lpm (struct ccw_device *cdev, void **buffer, int *length, __u8 lp
         rcd_ccw->count = ciw->count;
         rcd_ccw->flags = CCW_FLAG_SLI;
 
-        spin_lock_irq(&sch->lock);
+        spin_lock_irq(sch->lock);
         /* Save interrupt handler. */
         handler = cdev->handler;
         /* Temporarily install own handler. */
@@ -480,7 +480,7 @@ read_conf_data_lpm (struct ccw_device *cdev, void **buffer, int *length, __u8 lp
 
         /* Restore interrupt handler. */
         cdev->handler = handler;
-        spin_unlock_irq(&sch->lock);
+        spin_unlock_irq(sch->lock);
 
         /*
          * on success we update the user input parms
@@ -537,7 +537,7 @@ ccw_device_stlck(struct ccw_device *cdev)
                 kfree(buf);
                 return -ENOMEM;
         }
-        spin_lock_irqsave(&sch->lock, flags);
+        spin_lock_irqsave(sch->lock, flags);
         ret = cio_enable_subchannel(sch, 3);
         if (ret)
                 goto out_unlock;
@@ -559,9 +559,9 @@ ccw_device_stlck(struct ccw_device *cdev)
                 goto out_unlock;
         }
         cdev->private->irb.scsw.actl |= SCSW_ACTL_START_PEND;
-        spin_unlock_irqrestore(&sch->lock, flags);
+        spin_unlock_irqrestore(sch->lock, flags);
         wait_event(cdev->private->wait_q, cdev->private->irb.scsw.actl == 0);
-        spin_lock_irqsave(&sch->lock, flags);
+        spin_lock_irqsave(sch->lock, flags);
         cio_disable_subchannel(sch); //FIXME: return code?
         if ((cdev->private->irb.scsw.dstat !=
              (DEV_STAT_CHN_END|DEV_STAT_DEV_END)) ||
@@ -572,7 +572,7 @@ ccw_device_stlck(struct ccw_device *cdev)
 out_unlock:
         kfree(buf);
         kfree(buf2);
-        spin_unlock_irqrestore(&sch->lock, flags);
+        spin_unlock_irqrestore(sch->lock, flags);
         return ret;
 }