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>

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index a34adc2..06a92c5 100644 (file)
--- 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 ff1822a..f3ad024 100644 (file)
--- 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;