Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 422 insertions, 43 deletions

diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 52fdf60bdbe..83d5c88e716 100644
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -23,44 +23,74 @@
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/list.h>
 
+#include <asm/io.h>
 #include <asm/xen/hypervisor.h>
 
 #include <xen/xen.h>
+#include <xen/interface/xen.h>
+#include <xen/hvm.h>
+#include <xen/grant_table.h>
 #include <xen/page.h>
 #include <xen/events.h>
 #include <xen/interface/io/console.h>
 #include <xen/hvc-console.h>
+#include <xen/xenbus.h>
 
 #include "hvc_console.h"
 
 #define HVC_COOKIE   0x58656e /* "Xen" in hex */
 
-static struct hvc_struct *hvc;
-static int xencons_irq;
+struct xencons_info {
+	struct list_head list;
+	struct xenbus_device *xbdev;
+	struct xencons_interface *intf;
+	unsigned int evtchn;
+	struct hvc_struct *hvc;
+	int irq;
+	int vtermno;
+	grant_ref_t gntref;
+};
+
+static LIST_HEAD(xenconsoles);
+static DEFINE_SPINLOCK(xencons_lock);
 
 /* ------------------------------------------------------------------ */
 
-static unsigned long console_pfn = ~0ul;
+static struct xencons_info *vtermno_to_xencons(int vtermno)
+{
+	struct xencons_info *entry, *n, *ret = NULL;
+
+	if (list_empty(&xenconsoles))
+			return NULL;
+
+	list_for_each_entry_safe(entry, n, &xenconsoles, list) {
+		if (entry->vtermno == vtermno) {
+			ret  = entry;
+			break;
+		}
+	}
+
+	return ret;
+}
 
-static inline struct xencons_interface *xencons_interface(void)
+static inline int xenbus_devid_to_vtermno(int devid)
 {
-	if (console_pfn == ~0ul)
-		return mfn_to_virt(xen_start_info->console.domU.mfn);
-	else
-		return __va(console_pfn << PAGE_SHIFT);
+	return devid + HVC_COOKIE;
 }
 
-static inline void notify_daemon(void)
+static inline void notify_daemon(struct xencons_info *cons)
 {
 	/* Use evtchn: this is called early, before irq is set up. */
-	notify_remote_via_evtchn(xen_start_info->console.domU.evtchn);
+	notify_remote_via_evtchn(cons->evtchn);
 }
 
-static int __write_console(const char *data, int len)
+static int __write_console(struct xencons_info *xencons,
+		const char *data, int len)
 {
-	struct xencons_interface *intf = xencons_interface();
 	XENCONS_RING_IDX cons, prod;
+	struct xencons_interface *intf = xencons->intf;
 	int sent = 0;
 
 	cons = intf->out_cons;
@@ -75,13 +105,16 @@ static int __write_console(const char *data, int len)
 	intf->out_prod = prod;
 
 	if (sent)
-		notify_daemon();
+		notify_daemon(xencons);
 	return sent;
 }
 
 static int domU_write_console(uint32_t vtermno, const char *data, int len)
 {
 	int ret = len;
+	struct xencons_info *cons = vtermno_to_xencons(vtermno);
+	if (cons == NULL)
+		return -EINVAL;
 
 	/*
 	 * Make sure the whole buffer is emitted, polling if
@@ -90,7 +123,7 @@ static int domU_write_console(uint32_t vtermno, const char *data, int len)
 	 * kernel is crippled.
 	 */
 	while (len) {
-		int sent = __write_console(data, len);
+		int sent = __write_console(cons, data, len);
 		
 		data += sent;
 		len -= sent;
@@ -104,9 +137,13 @@ static int domU_write_console(uint32_t vtermno, const char *data, int len)
 
 static int domU_read_console(uint32_t vtermno, char *buf, int len)
 {
-	struct xencons_interface *intf = xencons_interface();
+	struct xencons_interface *intf;
 	XENCONS_RING_IDX cons, prod;
 	int recv = 0;
+	struct xencons_info *xencons = vtermno_to_xencons(vtermno);
+	if (xencons == NULL)
+		return -EINVAL;
+	intf = xencons->intf;
 
 	cons = intf->in_cons;
 	prod = intf->in_prod;
@@ -119,7 +156,7 @@ static int domU_read_console(uint32_t vtermno, char *buf, int len)
 	mb();			/* read ring before consuming */
 	intf->in_cons = cons;
 
-	notify_daemon();
+	notify_daemon(xencons);
 	return recv;
 }
 
@@ -157,68 +194,407 @@ static struct hv_ops dom0_hvc_ops = {
 	.notifier_hangup = notifier_hangup_irq,
 };
 
-static int __init xen_hvc_init(void)
+static int xen_hvm_console_init(void)
+{
+	int r;
+	uint64_t v = 0;
+	unsigned long mfn;
+	struct xencons_info *info;
+
+	if (!xen_hvm_domain())
+		return -ENODEV;
+
+	info = vtermno_to_xencons(HVC_COOKIE);
+	if (!info) {
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL | __GFP_ZERO);
+		if (!info)
+			return -ENOMEM;
+	}
+
+	/* already configured */
+	if (info->intf != NULL)
+		return 0;
+
+	r = hvm_get_parameter(HVM_PARAM_CONSOLE_EVTCHN, &v);
+	if (r < 0) {
+		kfree(info);
+		return -ENODEV;
+	}
+	info->evtchn = v;
+	hvm_get_parameter(HVM_PARAM_CONSOLE_PFN, &v);
+	if (r < 0) {
+		kfree(info);
+		return -ENODEV;
+	}
+	mfn = v;
+	info->intf = ioremap(mfn << PAGE_SHIFT, PAGE_SIZE);
+	if (info->intf == NULL) {
+		kfree(info);
+		return -ENODEV;
+	}
+	info->vtermno = HVC_COOKIE;
+
+	spin_lock(&xencons_lock);
+	list_add_tail(&info->list, &xenconsoles);
+	spin_unlock(&xencons_lock);
+
+	return 0;
+}
+
+static int xen_pv_console_init(void)
 {
-	struct hvc_struct *hp;
-	struct hv_ops *ops;
+	struct xencons_info *info;
 
 	if (!xen_pv_domain())
 		return -ENODEV;
 
-	if (xen_initial_domain()) {
-		ops = &dom0_hvc_ops;
-		xencons_irq = bind_virq_to_irq(VIRQ_CONSOLE, 0);
-	} else {
-		if (!xen_start_info->console.domU.evtchn)
-			return -ENODEV;
+	if (!xen_start_info->console.domU.evtchn)
+		return -ENODEV;
 
-		ops = &domU_hvc_ops;
-		xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
+	info = vtermno_to_xencons(HVC_COOKIE);
+	if (!info) {
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL | __GFP_ZERO);
+		if (!info)
+			return -ENOMEM;
 	}
-	if (xencons_irq < 0)
-		xencons_irq = 0; /* NO_IRQ */
-	else
-		irq_set_noprobe(xencons_irq);
 
-	hp = hvc_alloc(HVC_COOKIE, xencons_irq, ops, 256);
-	if (IS_ERR(hp))
-		return PTR_ERR(hp);
+	/* already configured */
+	if (info->intf != NULL)
+		return 0;
+
+	info->evtchn = xen_start_info->console.domU.evtchn;
+	info->intf = mfn_to_virt(xen_start_info->console.domU.mfn);
+	info->vtermno = HVC_COOKIE;
+
+	spin_lock(&xencons_lock);
+	list_add_tail(&info->list, &xenconsoles);
+	spin_unlock(&xencons_lock);
+
+	return 0;
+}
+
+static int xen_initial_domain_console_init(void)
+{
+	struct xencons_info *info;
+
+	if (!xen_initial_domain())
+		return -ENODEV;
+
+	info = vtermno_to_xencons(HVC_COOKIE);
+	if (!info) {
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL | __GFP_ZERO);
+		if (!info)
+			return -ENOMEM;
+	}
 
-	hvc = hp;
+	info->irq = bind_virq_to_irq(VIRQ_CONSOLE, 0);
+	info->vtermno = HVC_COOKIE;
 
-	console_pfn = mfn_to_pfn(xen_start_info->console.domU.mfn);
+	spin_lock(&xencons_lock);
+	list_add_tail(&info->list, &xenconsoles);
+	spin_unlock(&xencons_lock);
 
 	return 0;
 }
 
 void xen_console_resume(void)
 {
-	if (xencons_irq)
-		rebind_evtchn_irq(xen_start_info->console.domU.evtchn, xencons_irq);
+	struct xencons_info *info = vtermno_to_xencons(HVC_COOKIE);
+	if (info != NULL && info->irq)
+		rebind_evtchn_irq(info->evtchn, info->irq);
+}
+
+static void xencons_disconnect_backend(struct xencons_info *info)
+{
+	if (info->irq > 0)
+		unbind_from_irqhandler(info->irq, NULL);
+	info->irq = 0;
+	if (info->evtchn > 0)
+		xenbus_free_evtchn(info->xbdev, info->evtchn);
+	info->evtchn = 0;
+	if (info->gntref > 0)
+		gnttab_free_grant_references(info->gntref);
+	info->gntref = 0;
+	if (info->hvc != NULL)
+		hvc_remove(info->hvc);
+	info->hvc = NULL;
+}
+
+static void xencons_free(struct xencons_info *info)
+{
+	free_page((unsigned long)info->intf);
+	info->intf = NULL;
+	info->vtermno = 0;
+	kfree(info);
+}
+
+static int xen_console_remove(struct xencons_info *info)
+{
+	xencons_disconnect_backend(info);
+	spin_lock(&xencons_lock);
+	list_del(&info->list);
+	spin_unlock(&xencons_lock);
+	if (info->xbdev != NULL)
+		xencons_free(info);
+	else {
+		if (xen_hvm_domain())
+			iounmap(info->intf);
+		kfree(info);
+	}
+	return 0;
+}
+
+#ifdef CONFIG_HVC_XEN_FRONTEND
+static struct xenbus_driver xencons_driver;
+
+static int xencons_remove(struct xenbus_device *dev)
+{
+	return xen_console_remove(dev_get_drvdata(&dev->dev));
+}
+
+static int xencons_connect_backend(struct xenbus_device *dev,
+				  struct xencons_info *info)
+{
+	int ret, evtchn, devid, ref, irq;
+	struct xenbus_transaction xbt;
+	grant_ref_t gref_head;
+	unsigned long mfn;
+
+	ret = xenbus_alloc_evtchn(dev, &evtchn);
+	if (ret)
+		return ret;
+	info->evtchn = evtchn;
+	irq = bind_evtchn_to_irq(evtchn);
+	if (irq < 0)
+		return irq;
+	info->irq = irq;
+	devid = dev->nodename[strlen(dev->nodename) - 1] - '0';
+	info->hvc = hvc_alloc(xenbus_devid_to_vtermno(devid),
+			irq, &domU_hvc_ops, 256);
+	if (IS_ERR(info->hvc))
+		return PTR_ERR(info->hvc);
+	if (xen_pv_domain())
+		mfn = virt_to_mfn(info->intf);
+	else
+		mfn = __pa(info->intf) >> PAGE_SHIFT;
+	ret = gnttab_alloc_grant_references(1, &gref_head);
+	if (ret < 0)
+		return ret;
+	info->gntref = gref_head;
+	ref = gnttab_claim_grant_reference(&gref_head);
+	if (ref < 0)
+		return ref;
+	gnttab_grant_foreign_access_ref(ref, info->xbdev->otherend_id,
+			mfn, 0);
+
+ again:
+	ret = xenbus_transaction_start(&xbt);
+	if (ret) {
+		xenbus_dev_fatal(dev, ret, "starting transaction");
+		return ret;
+	}
+	ret = xenbus_printf(xbt, dev->nodename, "ring-ref", "%d", ref);
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_printf(xbt, dev->nodename, "port", "%u",
+			    evtchn);
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_printf(xbt, dev->nodename, "type", "ioemu");
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_transaction_end(xbt, 0);
+	if (ret) {
+		if (ret == -EAGAIN)
+			goto again;
+		xenbus_dev_fatal(dev, ret, "completing transaction");
+		return ret;
+	}
+
+	xenbus_switch_state(dev, XenbusStateInitialised);
+	return 0;
+
+ error_xenbus:
+	xenbus_transaction_end(xbt, 1);
+	xenbus_dev_fatal(dev, ret, "writing xenstore");
+	return ret;
+}
+
+static int __devinit xencons_probe(struct xenbus_device *dev,
+				  const struct xenbus_device_id *id)
+{
+	int ret, devid;
+	struct xencons_info *info;
+
+	devid = dev->nodename[strlen(dev->nodename) - 1] - '0';
+	if (devid == 0)
+		return -ENODEV;
+
+	info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL | __GFP_ZERO);
+	if (!info)
+		goto error_nomem;
+	dev_set_drvdata(&dev->dev, info);
+	info->xbdev = dev;
+	info->vtermno = xenbus_devid_to_vtermno(devid);
+	info->intf = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
+	if (!info->intf)
+		goto error_nomem;
+
+	ret = xencons_connect_backend(dev, info);
+	if (ret < 0)
+		goto error;
+	spin_lock(&xencons_lock);
+	list_add_tail(&info->list, &xenconsoles);
+	spin_unlock(&xencons_lock);
+
+	return 0;
+
+ error_nomem:
+	ret = -ENOMEM;
+	xenbus_dev_fatal(dev, ret, "allocating device memory");
+ error:
+	xencons_disconnect_backend(info);
+	xencons_free(info);
+	return ret;
+}
+
+static int xencons_resume(struct xenbus_device *dev)
+{
+	struct xencons_info *info = dev_get_drvdata(&dev->dev);
+
+	xencons_disconnect_backend(info);
+	memset(info->intf, 0, PAGE_SIZE);
+	return xencons_connect_backend(dev, info);
+}
+
+static void xencons_backend_changed(struct xenbus_device *dev,
+				   enum xenbus_state backend_state)
+{
+	switch (backend_state) {
+	case XenbusStateReconfiguring:
+	case XenbusStateReconfigured:
+	case XenbusStateInitialising:
+	case XenbusStateInitialised:
+	case XenbusStateUnknown:
+	case XenbusStateClosed:
+		break;
+
+	case XenbusStateInitWait:
+		break;
+
+	case XenbusStateConnected:
+		xenbus_switch_state(dev, XenbusStateConnected);
+		break;
+
+	case XenbusStateClosing:
+		xenbus_frontend_closed(dev);
+		break;
+	}
+}
+
+static const struct xenbus_device_id xencons_ids[] = {
+	{ "console" },
+	{ "" }
+};
+
+
+static DEFINE_XENBUS_DRIVER(xencons, "xenconsole",
+	.probe = xencons_probe,
+	.remove = xencons_remove,
+	.resume = xencons_resume,
+	.otherend_changed = xencons_backend_changed,
+);
+#endif /* CONFIG_HVC_XEN_FRONTEND */
+
+static int __init xen_hvc_init(void)
+{
+	int r;
+	struct xencons_info *info;
+	const struct hv_ops *ops;
+
+	if (!xen_domain())
+		return -ENODEV;
+
+	if (xen_initial_domain()) {
+		ops = &dom0_hvc_ops;
+		r = xen_initial_domain_console_init();
+		if (r < 0)
+			return r;
+		info = vtermno_to_xencons(HVC_COOKIE);
+	} else {
+		ops = &domU_hvc_ops;
+		if (xen_hvm_domain())
+			r = xen_hvm_console_init();
+		else
+			r = xen_pv_console_init();
+		if (r < 0)
+			return r;
+
+		info = vtermno_to_xencons(HVC_COOKIE);
+		info->irq = bind_evtchn_to_irq(info->evtchn);
+	}
+	if (info->irq < 0)
+		info->irq = 0; /* NO_IRQ */
+	else
+		irq_set_noprobe(info->irq);
+
+	info->hvc = hvc_alloc(HVC_COOKIE, info->irq, ops, 256);
+	if (IS_ERR(info->hvc)) {
+		r = PTR_ERR(info->hvc);
+		spin_lock(&xencons_lock);
+		list_del(&info->list);
+		spin_unlock(&xencons_lock);
+		if (info->irq)
+			unbind_from_irqhandler(info->irq, NULL);
+		kfree(info);
+		return r;
+	}
+
+	r = 0;
+#ifdef CONFIG_HVC_XEN_FRONTEND
+	r = xenbus_register_frontend(&xencons_driver);
+#endif
+	return r;
 }
 
 static void __exit xen_hvc_fini(void)
 {
-	if (hvc)
-		hvc_remove(hvc);
+	struct xencons_info *entry, *next;
+
+	if (list_empty(&xenconsoles))
+			return;
+
+	list_for_each_entry_safe(entry, next, &xenconsoles, list) {
+		xen_console_remove(entry);
+	}
 }
 
 static int xen_cons_init(void)
 {
-	struct hv_ops *ops;
+	const struct hv_ops *ops;
 
-	if (!xen_pv_domain())
+	if (!xen_domain())
 		return 0;
 
 	if (xen_initial_domain())
 		ops = &dom0_hvc_ops;
-	else
+	else {
+		int r;
 		ops = &domU_hvc_ops;
 
+		if (xen_hvm_domain())
+			r = xen_hvm_console_init();
+		else
+			r = xen_pv_console_init();
+		if (r < 0)
+			return r;
+	}
+
 	hvc_instantiate(HVC_COOKIE, 0, ops);
 	return 0;
 }
 
+
 module_init(xen_hvc_init);
 module_exit(xen_hvc_fini);
 console_initcall(xen_cons_init);
@@ -230,6 +606,9 @@ static void xenboot_write_console(struct console *console, const char *string,
 	unsigned int linelen, off = 0;
 	const char *pos;
 
+	if (!xen_pv_domain())
+		return;
+
 	dom0_write_console(0, string, len);
 
 	if (xen_initial_domain())