Merge branch 'x86-hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[~andy/linux] / drivers / scsi / scsi_transport_iscsi.c

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index b9aec304872cbd5ddec34465a285b9e19dac5eff..e84026def1f4839b69032a8ea76916c07f871645 100644 (file)
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -30,6 +30,7 @@
 #include <scsi/scsi_transport.h>
 #include <scsi/scsi_transport_iscsi.h>
 #include <scsi/iscsi_if.h>
+#include <scsi/scsi_cmnd.h>
 
 #define ISCSI_SESSION_ATTRS 23
 #define ISCSI_CONN_ATTRS 13
@@ -534,6 +535,37 @@ static void iscsi_scan_session(struct work_struct *work)
        atomic_dec(&ihost->nr_scans);
 }
 
+/**
+ * iscsi_block_scsi_eh - block scsi eh until session state has transistioned
+ * cmd: scsi cmd passed to scsi eh handler
+ *
+ * If the session is down this function will wait for the recovery
+ * timer to fire or for the session to be logged back in. If the
+ * recovery timer fires then FAST_IO_FAIL is returned. The caller
+ * should pass this error value to the scsi eh.
+ */
+int iscsi_block_scsi_eh(struct scsi_cmnd *cmd)
+{
+       struct iscsi_cls_session *session =
+                       starget_to_session(scsi_target(cmd->device));
+       unsigned long flags;
+       int ret = 0;
+
+       spin_lock_irqsave(&session->lock, flags);
+       while (session->state != ISCSI_SESSION_LOGGED_IN) {
+               if (session->state == ISCSI_SESSION_FREE) {
+                       ret = FAST_IO_FAIL;
+                       break;
+               }
+               spin_unlock_irqrestore(&session->lock, flags);
+               msleep(1000);
+               spin_lock_irqsave(&session->lock, flags);
+       }
+       spin_unlock_irqrestore(&session->lock, flags);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(iscsi_block_scsi_eh);
+
 static void session_recovery_timedout(struct work_struct *work)
 {
        struct iscsi_cls_session *session =
@@ -1783,14 +1815,42 @@ show_priv_session_##field(struct device *dev,                           \
 {                                                                      \
        struct iscsi_cls_session *session =                             \
                        iscsi_dev_to_session(dev->parent);              \
+       if (session->field == -1)                                       \
+               return sprintf(buf, "off\n");                           \
        return sprintf(buf, format"\n", session->field);                \
 }
 
-#define iscsi_priv_session_attr(field, format)                         \
+#define iscsi_priv_session_attr_store(field)                           \
+static ssize_t                                                         \
+store_priv_session_##field(struct device *dev,                         \
+                          struct device_attribute *attr,               \
+                          const char *buf, size_t count)               \
+{                                                                      \
+       int val;                                                        \
+       char *cp;                                                       \
+       struct iscsi_cls_session *session =                             \
+               iscsi_dev_to_session(dev->parent);                      \
+       if ((session->state == ISCSI_SESSION_FREE) ||                   \
+           (session->state == ISCSI_SESSION_FAILED))                   \
+               return -EBUSY;                                          \
+       if (strncmp(buf, "off", 3) == 0)                                \
+               session->field = -1;                                    \
+       else {                                                          \
+               val = simple_strtoul(buf, &cp, 0);                      \
+               if (*cp != '\0' && *cp != '\n')                         \
+                       return -EINVAL;                                 \
+               session->field = val;                                   \
+       }                                                               \
+       return count;                                                   \
+}
+
+#define iscsi_priv_session_rw_attr(field, format)                      \
        iscsi_priv_session_attr_show(field, format)                     \
-static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
-                       NULL)
-iscsi_priv_session_attr(recovery_tmo, "%d");
+       iscsi_priv_session_attr_store(field)                            \
+static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO | S_IWUGO,           \
+                       show_priv_session_##field,                      \
+                       store_priv_session_##field)
+iscsi_priv_session_rw_attr(recovery_tmo, "%d");
 
 /*
  * iSCSI host attrs
@@ -1821,6 +1881,11 @@ do {                                                                     \
        count++;                                                        \
 } while (0)
 
+#define SETUP_PRIV_SESSION_RW_ATTR(field)                              \
+do {                                                                   \
+       priv->session_attrs[count] = &dev_attr_priv_sess_##field;       \
+       count++;                                                        \
+} while (0)
 
 #define SETUP_SESSION_RD_ATTR(field, param_flag)                       \
 do {                                                                   \
@@ -2008,7 +2073,7 @@ iscsi_register_transport(struct iscsi_transport *tt)
        SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
        SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
        SETUP_SESSION_RD_ATTR(targetalias, ISCSI_TARGET_ALIAS);
-       SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
+       SETUP_PRIV_SESSION_RW_ATTR(recovery_tmo);
        SETUP_PRIV_SESSION_RD_ATTR(state);
 
        BUG_ON(count > ISCSI_SESSION_ATTRS);