[PATCH] libata: fix autopsy ehc->i.action and ehc->i.dev handling

Commit 0662c58b3265f52f708a6d59476bc7862b01f9c0 updated
ata_eh_autopsy() to OR determined action to ehc->i.action to preserve
action mask set directly into ehc->i.action by nested functions.  This
broke action mask clearing on SENSE_VALID case causing revalidation
and EH complete message on successful ATAPI CC.

This patch removes two local variables - action and failed_dev - which
cache ehc->i.action and ehc->i.dev respectively, and make the function
directly modify ehc->i.* fields to remove aliasing issues.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 12 insertions, 17 deletions

diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index 4b6aa30f4d68..36a801c83325 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -1276,8 +1276,6 @@ static int ata_eh_speed_down(struct ata_device *dev, int is_io,
 static void ata_eh_autopsy(struct ata_port *ap)
 {
         struct ata_eh_context *ehc = &ap->eh_context;
-        unsigned int action = ehc->i.action;
-        struct ata_device *failed_dev = NULL;
         unsigned int all_err_mask = 0;
         int tag, is_io = 0;
         u32 serror;
@@ -1294,7 +1292,7 @@ static void ata_eh_autopsy(struct ata_port *ap)
                 ehc->i.serror |= serror;
                 ata_eh_analyze_serror(ap);
         } else if (rc != -EOPNOTSUPP)
-                action |= ATA_EH_HARDRESET;
+                ehc->i.action |= ATA_EH_HARDRESET;
 
         /* analyze NCQ failure */
         ata_eh_analyze_ncq_error(ap);
@@ -1315,7 +1313,7 @@ static void ata_eh_autopsy(struct ata_port *ap)
                 qc->err_mask |= ehc->i.err_mask;
 
                 /* analyze TF */
-                action |= ata_eh_analyze_tf(qc, &qc->result_tf);
+                ehc->i.action |= ata_eh_analyze_tf(qc, &qc->result_tf);
 
                 /* DEV errors are probably spurious in case of ATA_BUS error */
                 if (qc->err_mask & AC_ERR_ATA_BUS)
@@ -1329,11 +1327,11 @@ static void ata_eh_autopsy(struct ata_port *ap)
                 /* SENSE_VALID trumps dev/unknown error and revalidation */
                 if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
                         qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
-                        action &= ~ATA_EH_REVALIDATE;
+                        ehc->i.action &= ~ATA_EH_REVALIDATE;
                 }
 
                 /* accumulate error info */
-                failed_dev = qc->dev;
+                ehc->i.dev = qc->dev;
                 all_err_mask |= qc->err_mask;
                 if (qc->flags & ATA_QCFLAG_IO)
                         is_io = 1;
@@ -1342,25 +1340,22 @@ static void ata_eh_autopsy(struct ata_port *ap)
         /* enforce default EH actions */
         if (ap->pflags & ATA_PFLAG_FROZEN ||
             all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
-                action |= ATA_EH_SOFTRESET;
+                ehc->i.action |= ATA_EH_SOFTRESET;
         else if (all_err_mask)
-                action |= ATA_EH_REVALIDATE;
+                ehc->i.action |= ATA_EH_REVALIDATE;
 
         /* if we have offending qcs and the associated failed device */
-        if (failed_dev) {
+        if (ehc->i.dev) {
                 /* speed down */
-                action |= ata_eh_speed_down(failed_dev, is_io, all_err_mask);
+                ehc->i.action |= ata_eh_speed_down(ehc->i.dev, is_io,
+                                                   all_err_mask);
 
                 /* perform per-dev EH action only on the offending device */
-                ehc->i.dev_action[failed_dev->devno] |=
-                        action & ATA_EH_PERDEV_MASK;
-                action &= ~ATA_EH_PERDEV_MASK;
+                ehc->i.dev_action[ehc->i.dev->devno] |=
+                        ehc->i.action & ATA_EH_PERDEV_MASK;
+                ehc->i.action &= ~ATA_EH_PERDEV_MASK;
         }
 
-        /* record autopsy result */
-        ehc->i.dev = failed_dev;
-        ehc->i.action |= action;
-
         DPRINTK("EXIT\n");
 }