libata: move reset freeze/thaw handling into ata_eh_reset()

Previously reset freeze/thaw handling lived outside of ata_eh_reset()
mainly because the original PMP reset code needed the port frozen
while resetting all the fan-out ports, which is no longer the case.

This patch moves freeze/thaw handling into ata_eh_reset().
@prereset() and @postreset() are now called w/o freezing the port
although @prereset() an be called frozen if the port is frozen prior
to entering ata_eh_reset().

This makes code simpler and will help removing hotplug event related
races.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

2 files changed, 18 insertions, 32 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index a34adc2c85df..06a92c58a49d 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -2170,6 +2170,9 @@ int ata_eh_reset(struct ata_link *link, int classify,
         /*
          * Perform reset
          */
+        if (ata_is_host_link(link))
+                ata_eh_freeze_port(ap);
+
         deadline = jiffies + ata_eh_reset_timeouts[try++];
 
         if (reset) {
@@ -2238,6 +2241,10 @@ int ata_eh_reset(struct ata_link *link, int classify,
         if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
                 link->sata_spd = (sstatus >> 4) & 0xf;
 
+        /* thaw the port */
+        if (ata_is_host_link(link))
+                ata_eh_thaw_port(ap);
+
         if (postreset)
                 postreset(link, classes);
 
@@ -2589,7 +2596,7 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
         struct ata_link *link;
         struct ata_device *dev;
         int nr_failed_devs, nr_disabled_devs;
-        int reset, rc;
+        int rc;
         unsigned long flags;
 
         DPRINTK("ENTER\n");
@@ -2632,7 +2639,6 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
         rc = 0;
         nr_failed_devs = 0;
         nr_disabled_devs = 0;
-        reset = 0;
 
         /* if UNLOADING, finish immediately */
         if (ap->pflags & ATA_PFLAG_UNLOADING)
@@ -2646,40 +2652,24 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
                 if (ata_eh_skip_recovery(link))
                         ehc->i.action = 0;
 
-                /* do we need to reset? */
-                if (ehc->i.action & ATA_EH_RESET)
-                        reset = 1;
-
                 ata_link_for_each_dev(dev, link)
                         ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
         }
 
         /* reset */
-        if (reset) {
-                /* if PMP is attached, this function only deals with
-                 * downstream links, port should stay thawed.
-                 */
-                if (!sata_pmp_attached(ap))
-                        ata_eh_freeze_port(ap);
-
-                ata_port_for_each_link(link, ap) {
-                        struct ata_eh_context *ehc = &link->eh_context;
+        ata_port_for_each_link(link, ap) {
+                struct ata_eh_context *ehc = &link->eh_context;
 
-                        if (!(ehc->i.action & ATA_EH_RESET))
-                                continue;
+                if (!(ehc->i.action & ATA_EH_RESET))
+                        continue;
 
-                        rc = ata_eh_reset(link, ata_link_nr_vacant(link),
-                                          prereset, softreset, hardreset,
-                                          postreset);
-                        if (rc) {
-                                ata_link_printk(link, KERN_ERR,
-                                                "reset failed, giving up\n");
-                                goto out;
-                        }
+                rc = ata_eh_reset(link, ata_link_nr_vacant(link),
+                                  prereset, softreset, hardreset, postreset);
+                if (rc) {
+                        ata_link_printk(link, KERN_ERR,
+                                        "reset failed, giving up\n");
+                        goto out;
                 }
-
-                if (!sata_pmp_attached(ap))
-                        ata_eh_thaw_port(ap);
         }
 
         /* the rest */
diff --git a/drivers/ata/libata-pmp.c b/drivers/ata/libata-pmp.c
index ff1822a7da38..f3ad024394c2 100644
--- a/drivers/ata/libata-pmp.c
+++ b/drivers/ata/libata-pmp.c
@@ -700,8 +700,6 @@ static int sata_pmp_eh_recover_pmp(struct ata_port *ap,
         if (ehc->i.action & ATA_EH_RESET) {
                 struct ata_link *tlink;
 
-                ata_eh_freeze_port(ap);
-
                 /* reset */
                 rc = ata_eh_reset(link, 0, prereset, softreset, hardreset,
                                   postreset);
@@ -711,8 +709,6 @@ static int sata_pmp_eh_recover_pmp(struct ata_port *ap,
                         goto fail;
                 }
 
-                ata_eh_thaw_port(ap);
-
                 /* PMP is reset, SErrors cannot be trusted, scan all */
                 ata_port_for_each_link(tlink, ap) {
                         struct ata_eh_context *ehc = &tlink->eh_context;