libata: kill ATA_FLAG_DISABLED

ATA_FLAG_DISABLED is only used by drivers which don't use
->error_handler framework and is largely broken.  Its only meaningful
function is to make irq handlers skip processing if the flag is set,
which is largely useless and even harmful as it makes those ports more
likely to cause IRQ storms.

Kill ATA_FLAG_DISABLED and makes the callers disable attached devices
instead.  ata_port_probe() and ata_port_disable() which manipulate the
flag are also killed.

This simplifies condition check in IRQ handlers.  While updating IRQ
handlers, remove ap NULL check as libata guarantees consecutive port
allocation (unoccupied ports are initialized with dummies) and
long-obsolete ATA_QCFLAG_ACTIVE check (checked by ata_qc_from_tag()).

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 1 insertions, 65 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 86f405b4831..3d8b62f7441 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -1907,22 +1907,6 @@ unsigned ata_exec_internal_sg(struct ata_device *dev,
         ap->qc_active = preempted_qc_active;
         ap->nr_active_links = preempted_nr_active_links;
 
-        /* XXX - Some LLDDs (sata_mv) disable port on command failure.
-         * Until those drivers are fixed, we detect the condition
-         * here, fail the command with AC_ERR_SYSTEM and reenable the
-         * port.
-         *
-         * Note that this doesn't change any behavior as internal
-         * command failure results in disabling the device in the
-         * higher layer for LLDDs without new reset/EH callbacks.
-         *
-         * Kill the following code as soon as those drivers are fixed.
-         */
-        if (ap->flags & ATA_FLAG_DISABLED) {
-                err_mask |= AC_ERR_SYSTEM;
-                ata_port_probe(ap);
-        }
-
         spin_unlock_irqrestore(ap->lock, flags);
 
         if ((err_mask & AC_ERR_TIMEOUT) && auto_timeout)
@@ -2768,8 +2752,6 @@ int ata_bus_probe(struct ata_port *ap)
         int rc;
         struct ata_device *dev;
 
-        ata_port_probe(ap);
-
         ata_for_each_dev(dev, &ap->link, ALL)
                 tries[dev->devno] = ATA_PROBE_MAX_TRIES;
 
@@ -2797,8 +2779,7 @@ int ata_bus_probe(struct ata_port *ap)
         ap->ops->phy_reset(ap);
 
         ata_for_each_dev(dev, &ap->link, ALL) {
-                if (!(ap->flags & ATA_FLAG_DISABLED) &&
-                    dev->class != ATA_DEV_UNKNOWN)
+                if (dev->class != ATA_DEV_UNKNOWN)
                         classes[dev->devno] = dev->class;
                 else
                         classes[dev->devno] = ATA_DEV_NONE;
@@ -2806,8 +2787,6 @@ int ata_bus_probe(struct ata_port *ap)
                 dev->class = ATA_DEV_UNKNOWN;
         }
 
-        ata_port_probe(ap);
-
         /* read IDENTIFY page and configure devices. We have to do the identify
            specific sequence bass-ackwards so that PDIAG- is released by
            the slave device */
@@ -2857,8 +2836,6 @@ int ata_bus_probe(struct ata_port *ap)
         ata_for_each_dev(dev, &ap->link, ENABLED)
                 return 0;
 
-        /* no device present, disable port */
-        ata_port_disable(ap);
         return -ENODEV;
 
  fail:
@@ -2890,22 +2867,6 @@ int ata_bus_probe(struct ata_port *ap)
 }
 
 /**
- *      ata_port_probe - Mark port as enabled
- *      @ap: Port for which we indicate enablement
- *
- *      Modify @ap data structure such that the system
- *      thinks that the entire port is enabled.
- *
- *      LOCKING: host lock, or some other form of
- *      serialization.
- */
-
-void ata_port_probe(struct ata_port *ap)
-{
-        ap->flags &= ~ATA_FLAG_DISABLED;
-}
-
-/**
  *      sata_print_link_status - Print SATA link status
  *      @link: SATA link to printk link status about
  *
@@ -2952,26 +2913,6 @@ struct ata_device *ata_dev_pair(struct ata_device *adev)
 }
 
 /**
- *      ata_port_disable - Disable port.
- *      @ap: Port to be disabled.
- *
- *      Modify @ap data structure such that the system
- *      thinks that the entire port is disabled, and should
- *      never attempt to probe or communicate with devices
- *      on this port.
- *
- *      LOCKING: host lock, or some other form of
- *      serialization.
- */
-
-void ata_port_disable(struct ata_port *ap)
-{
-        ap->link.device[0].class = ATA_DEV_NONE;
-        ap->link.device[1].class = ATA_DEV_NONE;
-        ap->flags |= ATA_FLAG_DISABLED;
-}
-
-/**
  *      sata_down_spd_limit - adjust SATA spd limit downward
  *      @link: Link to adjust SATA spd limit for
  *      @spd_limit: Additional limit
@@ -5716,7 +5657,6 @@ struct ata_port *ata_port_alloc(struct ata_host *host)
 
         ap->pflags |= ATA_PFLAG_INITIALIZING;
         ap->lock = &host->lock;
-        ap->flags = ATA_FLAG_DISABLED;
         ap->print_id = -1;
         ap->ctl = ATA_DEVCTL_OBS;
         ap->host = host;
@@ -6145,8 +6085,6 @@ static void async_port_probe(void *data, async_cookie_t cookie)
                 struct ata_eh_info *ehi = &ap->link.eh_info;
                 unsigned long flags;
 
-                ata_port_probe(ap);
-
                 /* kick EH for boot probing */
                 spin_lock_irqsave(ap->lock, flags);
 
@@ -6823,7 +6761,6 @@ EXPORT_SYMBOL_GPL(ata_port_start);
 EXPORT_SYMBOL_GPL(ata_do_set_mode);
 EXPORT_SYMBOL_GPL(ata_std_qc_defer);
 EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
-EXPORT_SYMBOL_GPL(ata_port_probe);
 EXPORT_SYMBOL_GPL(ata_dev_disable);
 EXPORT_SYMBOL_GPL(sata_set_spd);
 EXPORT_SYMBOL_GPL(ata_wait_after_reset);
@@ -6835,7 +6772,6 @@ EXPORT_SYMBOL_GPL(sata_std_hardreset);
 EXPORT_SYMBOL_GPL(ata_std_postreset);
 EXPORT_SYMBOL_GPL(ata_dev_classify);
 EXPORT_SYMBOL_GPL(ata_dev_pair);
-EXPORT_SYMBOL_GPL(ata_port_disable);
 EXPORT_SYMBOL_GPL(ata_ratelimit);
 EXPORT_SYMBOL_GPL(ata_wait_register);
 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);