1 files changed, 36 insertions, 10 deletions

diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index 561dec2481cb..e3877b6843c9 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -33,6 +33,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/gfp.h>
 #include <linux/pci.h>
 #include <linux/libata.h>
 #include <linux/highmem.h>
@@ -1667,6 +1668,7 @@ unsigned int ata_sff_host_intr(struct ata_port *ap,
 {
         struct ata_eh_info *ehi = &ap->link.eh_info;
         u8 status, host_stat = 0;
+        bool bmdma_stopped = false;
 
         VPRINTK("ata%u: protocol %d task_state %d\n",
                 ap->print_id, qc->tf.protocol, ap->hsm_task_state);
@@ -1699,6 +1701,7 @@ unsigned int ata_sff_host_intr(struct ata_port *ap,
 
                         /* before we do anything else, clear DMA-Start bit */
                         ap->ops->bmdma_stop(qc);
+                        bmdma_stopped = true;
 
                         if (unlikely(host_stat & ATA_DMA_ERR)) {
                                 /* error when transfering data to/from memory */
@@ -1716,8 +1719,14 @@ unsigned int ata_sff_host_intr(struct ata_port *ap,
 
         /* check main status, clearing INTRQ if needed */
         status = ata_sff_irq_status(ap);
-        if (status & ATA_BUSY)
-                goto idle_irq;
+        if (status & ATA_BUSY) {
+                if (bmdma_stopped) {
+                        /* BMDMA engine is already stopped, we're screwed */
+                        qc->err_mask |= AC_ERR_HSM;
+                        ap->hsm_task_state = HSM_ST_ERR;
+                } else
+                        goto idle_irq;
+        }
 
         /* ack bmdma irq events */
         ap->ops->sff_irq_clear(ap);
@@ -1762,13 +1771,16 @@ EXPORT_SYMBOL_GPL(ata_sff_host_intr);
 irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
 {
         struct ata_host *host = dev_instance;
+        bool retried = false;
         unsigned int i;
-        unsigned int handled = 0, polling = 0;
+        unsigned int handled, idle, polling;
         unsigned long flags;
 
         /* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
         spin_lock_irqsave(&host->lock, flags);
 
+retry:
+        handled = idle = polling = 0;
         for (i = 0; i < host->n_ports; i++) {
                 struct ata_port *ap = host->ports[i];
                 struct ata_queued_cmd *qc;
@@ -1782,7 +1794,8 @@ irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
                                 handled |= ata_sff_host_intr(ap, qc);
                         else
                                 polling |= 1 << i;
-                }
+                } else
+                        idle |= 1 << i;
         }
 
         /*
@@ -1790,7 +1803,9 @@ irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
          * asserting IRQ line, nobody cared will ensue.  Check IRQ
          * pending status if available and clear spurious IRQ.
          */
-        if (!handled) {
+        if (!handled && !retried) {
+                bool retry = false;
+
                 for (i = 0; i < host->n_ports; i++) {
                         struct ata_port *ap = host->ports[i];
 
@@ -1801,12 +1816,23 @@ irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
                             !ap->ops->sff_irq_check(ap))
                                 continue;
 
-                        if (printk_ratelimit())
-                                ata_port_printk(ap, KERN_INFO,
-                                                "clearing spurious IRQ\n");
+                        if (idle & (1 << i)) {
+                                ap->ops->sff_check_status(ap);
+                                ap->ops->sff_irq_clear(ap);
+                        } else {
+                                /* clear INTRQ and check if BUSY cleared */
+                                if (!(ap->ops->sff_check_status(ap) & ATA_BUSY))
+                                        retry |= true;
+                                /*
+                                 * With command in flight, we can't do
+                                 * sff_irq_clear() w/o racing with completion.
+                                 */
+                        }
+                }
 
-                        ap->ops->sff_check_status(ap);
-                        ap->ops->sff_irq_clear(ap);
+                if (retry) {
+                        retried = true;
+                        goto retry;
                 }
         }