4 files changed, 32 insertions, 38 deletions

diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 50dcb68d8070..ab609255a0f3 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -780,6 +780,9 @@ static int __init balloon_init(void)
 	}
 #endif
 
+	/* Init the xen-balloon driver. */
+	xen_balloon_init();
+
 	return 0;
 }
 subsys_initcall(balloon_init);
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index d6786b87e13b..2c6a9114d332 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -42,6 +42,7 @@
 #include <linux/delay.h>
 #include <linux/hardirq.h>
 #include <linux/workqueue.h>
+#include <linux/ratelimit.h>
 
 #include <xen/xen.h>
 #include <xen/interface/xen.h>
@@ -1072,8 +1073,14 @@ static int gnttab_expand(unsigned int req_entries)
 	cur = nr_grant_frames;
 	extra = ((req_entries + (grefs_per_grant_frame-1)) /
 		 grefs_per_grant_frame);
-	if (cur + extra > gnttab_max_grant_frames())
+	if (cur + extra > gnttab_max_grant_frames()) {
+		pr_warn_ratelimited("xen/grant-table: max_grant_frames reached"
+				    " cur=%u extra=%u limit=%u"
+				    " gnttab_free_count=%u req_entries=%u\n",
+				    cur, extra, gnttab_max_grant_frames(),
+				    gnttab_free_count, req_entries);
 		return -ENOSPC;
+	}
 
 	rc = gnttab_map(cur, cur + extra - 1);
 	if (rc == 0)
diff --git a/drivers/xen/xen-balloon.c b/drivers/xen/xen-balloon.c
index e7715cb62eef..e89136ab851e 100644
--- a/drivers/xen/xen-balloon.c
+++ b/drivers/xen/xen-balloon.c
@@ -59,6 +59,8 @@ static void watch_target(struct xenbus_watch *watch,
 {
 	unsigned long long new_target;
 	int err;
+	static bool watch_fired;
+	static long target_diff;
 
 	err = xenbus_scanf(XBT_NIL, "memory", "target", "%llu", &new_target);
 	if (err != 1) {
@@ -69,7 +71,14 @@ static void watch_target(struct xenbus_watch *watch,
 	/* The given memory/target value is in KiB, so it needs converting to
 	 * pages. PAGE_SHIFT converts bytes to pages, hence PAGE_SHIFT - 10.
 	 */
-	balloon_set_new_target(new_target >> (PAGE_SHIFT - 10));
+	new_target >>= PAGE_SHIFT - 10;
+	if (watch_fired) {
+		balloon_set_new_target(new_target - target_diff);
+		return;
+	}
+
+	watch_fired = true;
+	target_diff = new_target - balloon_stats.target_pages;
 }
 static struct xenbus_watch target_watch = {
 	.node = "memory/target",
@@ -94,22 +103,15 @@ static struct notifier_block xenstore_notifier = {
 	.notifier_call = balloon_init_watcher,
 };
 
-static int __init balloon_init(void)
+void xen_balloon_init(void)
 {
-	if (!xen_domain())
-		return -ENODEV;
-
-	pr_info("Initialising balloon driver\n");
-
 	register_balloon(&balloon_dev);
 
 	register_xen_selfballooning(&balloon_dev);
 
 	register_xenstore_notifier(&xenstore_notifier);
-
-	return 0;
 }
-subsys_initcall(balloon_init);
+EXPORT_SYMBOL_GPL(xen_balloon_init);
 
 #define BALLOON_SHOW(name, format, args...)				\
 	static ssize_t show_##name(struct device *dev,			\
diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c
index d6950e0802b7..7bc88fd43cfc 100644
--- a/drivers/xen/xen-scsiback.c
+++ b/drivers/xen/xen-scsiback.c
@@ -134,11 +134,8 @@ struct vscsibk_pend {
 	struct page *pages[VSCSI_MAX_GRANTS];
 
 	struct se_cmd se_cmd;
-};
 
-struct scsiback_tmr {
-	atomic_t tmr_complete;
-	wait_queue_head_t tmr_wait;
+	struct completion tmr_done;
 };
 
 #define VSCSI_DEFAULT_SESSION_TAGS	128
@@ -599,36 +596,28 @@ static void scsiback_device_action(struct vscsibk_pend *pending_req,
 	struct scsiback_tpg *tpg = pending_req->v2p->tpg;
 	struct scsiback_nexus *nexus = tpg->tpg_nexus;
 	struct se_cmd *se_cmd = &pending_req->se_cmd;
-	struct scsiback_tmr *tmr;
 	u64 unpacked_lun = pending_req->v2p->lun;
 	int rc, err = FAILED;
 
-	tmr = kzalloc(sizeof(struct scsiback_tmr), GFP_KERNEL);
-	if (!tmr) {
-		target_put_sess_cmd(se_cmd);
-		goto err;
-	}
-
-	init_waitqueue_head(&tmr->tmr_wait);
+	init_completion(&pending_req->tmr_done);
 
 	rc = target_submit_tmr(&pending_req->se_cmd, nexus->tvn_se_sess,
 			       &pending_req->sense_buffer[0],
-			       unpacked_lun, tmr, act, GFP_KERNEL,
+			       unpacked_lun, NULL, act, GFP_KERNEL,
 			       tag, TARGET_SCF_ACK_KREF);
 	if (rc)
 		goto err;
 
-	wait_event(tmr->tmr_wait, atomic_read(&tmr->tmr_complete));
+	wait_for_completion(&pending_req->tmr_done);
 
 	err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
 		SUCCESS : FAILED;
 
 	scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
-	transport_generic_free_cmd(&pending_req->se_cmd, 1);
+	transport_generic_free_cmd(&pending_req->se_cmd, 0);
 	return;
+
 err:
-	if (tmr)
-		kfree(tmr);
 	scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
 }
 
@@ -1389,12 +1378,6 @@ static int scsiback_check_stop_free(struct se_cmd *se_cmd)
 static void scsiback_release_cmd(struct se_cmd *se_cmd)
 {
 	struct se_session *se_sess = se_cmd->se_sess;
-	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
-
-	if (se_tmr && se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
-		struct scsiback_tmr *tmr = se_tmr->fabric_tmr_ptr;
-		kfree(tmr);
-	}
 
 	percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
 }
@@ -1455,11 +1438,10 @@ static int scsiback_queue_status(struct se_cmd *se_cmd)
 
 static void scsiback_queue_tm_rsp(struct se_cmd *se_cmd)
 {
-	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
-	struct scsiback_tmr *tmr = se_tmr->fabric_tmr_ptr;
+	struct vscsibk_pend *pending_req = container_of(se_cmd,
+				struct vscsibk_pend, se_cmd);
 
-	atomic_set(&tmr->tmr_complete, 1);
-	wake_up(&tmr->tmr_wait);
+	complete(&pending_req->tmr_done);
 }
 
 static void scsiback_aborted_task(struct se_cmd *se_cmd)