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-rw-r--r--drivers/xen/xenbus/xenbus_client.c48
-rw-r--r--drivers/xen/xenbus/xenbus_comms.c21
-rw-r--r--drivers/xen/xenbus/xenbus_comms.h2
-rw-r--r--drivers/xen/xenbus/xenbus_dev_backend.c72
-rw-r--r--drivers/xen/xenbus/xenbus_dev_frontend.c6
-rw-r--r--drivers/xen/xenbus/xenbus_probe.c112
-rw-r--r--drivers/xen/xenbus/xenbus_probe.h9
-rw-r--r--drivers/xen/xenbus/xenbus_probe_backend.c10
-rw-r--r--drivers/xen/xenbus/xenbus_probe_frontend.c157
-rw-r--r--drivers/xen/xenbus/xenbus_xs.c107
10 files changed, 395 insertions, 149 deletions
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 566d2adbd6e..439c9dca9ee 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -30,6 +30,7 @@
* IN THE SOFTWARE.
*/
+#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/spinlock.h>
@@ -44,6 +45,7 @@
#include <xen/grant_table.h>
#include <xen/xenbus.h>
#include <xen/xen.h>
+#include <xen/features.h>
#include "xenbus_probe.h"
@@ -399,33 +401,6 @@ EXPORT_SYMBOL_GPL(xenbus_alloc_evtchn);
/**
- * Bind to an existing interdomain event channel in another domain. Returns 0
- * on success and stores the local port in *port. On error, returns -errno,
- * switches the device to XenbusStateClosing, and saves the error in XenStore.
- */
-int xenbus_bind_evtchn(struct xenbus_device *dev, int remote_port, int *port)
-{
- struct evtchn_bind_interdomain bind_interdomain;
- int err;
-
- bind_interdomain.remote_dom = dev->otherend_id;
- bind_interdomain.remote_port = remote_port;
-
- err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain,
- &bind_interdomain);
- if (err)
- xenbus_dev_fatal(dev, err,
- "binding to event channel %d from domain %d",
- remote_port, dev->otherend_id);
- else
- *port = bind_interdomain.local_port;
-
- return err;
-}
-EXPORT_SYMBOL_GPL(xenbus_bind_evtchn);
-
-
-/**
* Free an existing event channel. Returns 0 on success or -errno on error.
*/
int xenbus_free_evtchn(struct xenbus_device *dev, int port)
@@ -490,8 +465,7 @@ static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
op.host_addr = arbitrary_virt_to_machine(pte).maddr;
- if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
- BUG();
+ gnttab_batch_map(&op, 1);
if (op.status != GNTST_okay) {
free_vm_area(area);
@@ -534,7 +508,7 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
err = xenbus_map_ring(dev, gnt_ref, &node->handle, addr);
if (err)
- goto out_err;
+ goto out_err_free_ballooned_pages;
spin_lock(&xenbus_valloc_lock);
list_add(&node->next, &xenbus_valloc_pages);
@@ -543,8 +517,9 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
*vaddr = addr;
return 0;
- out_err:
+ out_err_free_ballooned_pages:
free_xenballooned_pages(1, &node->page);
+ out_err:
kfree(node);
return err;
}
@@ -569,11 +544,10 @@ int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
{
struct gnttab_map_grant_ref op;
- gnttab_set_map_op(&op, (phys_addr_t)vaddr, GNTMAP_host_map, gnt_ref,
+ gnttab_set_map_op(&op, (unsigned long)vaddr, GNTMAP_host_map, gnt_ref,
dev->otherend_id);
- if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
- BUG();
+ gnttab_batch_map(&op, 1);
if (op.status != GNTST_okay) {
xenbus_dev_fatal(dev, op.status,
@@ -662,7 +636,7 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
goto found;
}
}
- node = NULL;
+ node = addr = NULL;
found:
spin_unlock(&xenbus_valloc_lock);
@@ -698,7 +672,7 @@ int xenbus_unmap_ring(struct xenbus_device *dev,
{
struct gnttab_unmap_grant_ref op;
- gnttab_set_unmap_op(&op, (phys_addr_t)vaddr, GNTMAP_host_map, handle);
+ gnttab_set_unmap_op(&op, (unsigned long)vaddr, GNTMAP_host_map, handle);
if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
BUG();
@@ -743,7 +717,7 @@ static const struct xenbus_ring_ops ring_ops_hvm = {
void __init xenbus_ring_ops_init(void)
{
- if (xen_pv_domain())
+ if (!xen_feature(XENFEAT_auto_translated_physmap))
ring_ops = &ring_ops_pv;
else
ring_ops = &ring_ops_hvm;
diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c
index 2eff7a6aaa2..fdb0f339d0a 100644
--- a/drivers/xen/xenbus/xenbus_comms.c
+++ b/drivers/xen/xenbus/xenbus_comms.c
@@ -30,6 +30,8 @@
* IN THE SOFTWARE.
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <linux/wait.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
@@ -205,13 +207,12 @@ int xb_init_comms(void)
struct xenstore_domain_interface *intf = xen_store_interface;
if (intf->req_prod != intf->req_cons)
- printk(KERN_ERR "XENBUS request ring is not quiescent "
- "(%08x:%08x)!\n", intf->req_cons, intf->req_prod);
+ pr_err("request ring is not quiescent (%08x:%08x)!\n",
+ intf->req_cons, intf->req_prod);
if (intf->rsp_prod != intf->rsp_cons) {
- printk(KERN_WARNING "XENBUS response ring is not quiescent "
- "(%08x:%08x): fixing up\n",
- intf->rsp_cons, intf->rsp_prod);
+ pr_warn("response ring is not quiescent (%08x:%08x): fixing up\n",
+ intf->rsp_cons, intf->rsp_prod);
/* breaks kdump */
if (!reset_devices)
intf->rsp_cons = intf->rsp_prod;
@@ -224,8 +225,8 @@ int xb_init_comms(void)
int err;
err = bind_evtchn_to_irqhandler(xen_store_evtchn, wake_waiting,
0, "xenbus", &xb_waitq);
- if (err <= 0) {
- printk(KERN_ERR "XENBUS request irq failed %i\n", err);
+ if (err < 0) {
+ pr_err("request irq failed %i\n", err);
return err;
}
@@ -234,3 +235,9 @@ int xb_init_comms(void)
return 0;
}
+
+void xb_deinit_comms(void)
+{
+ unbind_from_irqhandler(xenbus_irq, &xb_waitq);
+ xenbus_irq = 0;
+}
diff --git a/drivers/xen/xenbus/xenbus_comms.h b/drivers/xen/xenbus/xenbus_comms.h
index 6e42800fa49..e74f9c1fbd8 100644
--- a/drivers/xen/xenbus/xenbus_comms.h
+++ b/drivers/xen/xenbus/xenbus_comms.h
@@ -35,6 +35,7 @@
int xs_init(void);
int xb_init_comms(void);
+void xb_deinit_comms(void);
/* Low level routines. */
int xb_write(const void *data, unsigned len);
@@ -44,6 +45,7 @@ int xb_wait_for_data_to_read(void);
int xs_input_avail(void);
extern struct xenstore_domain_interface *xen_store_interface;
extern int xen_store_evtchn;
+extern enum xenstore_init xen_store_domain_type;
extern const struct file_operations xen_xenbus_fops;
diff --git a/drivers/xen/xenbus/xenbus_dev_backend.c b/drivers/xen/xenbus/xenbus_dev_backend.c
index 3d3be78c109..b17707ee07d 100644
--- a/drivers/xen/xenbus/xenbus_dev_backend.c
+++ b/drivers/xen/xenbus/xenbus_dev_backend.c
@@ -1,3 +1,5 @@
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/mm.h>
@@ -8,7 +10,11 @@
#include <xen/xen.h>
#include <xen/page.h>
+#include <xen/xenbus.h>
#include <xen/xenbus_dev.h>
+#include <xen/grant_table.h>
+#include <xen/events.h>
+#include <asm/xen/hypervisor.h>
#include "xenbus_comms.h"
@@ -22,19 +28,65 @@ static int xenbus_backend_open(struct inode *inode, struct file *filp)
return nonseekable_open(inode, filp);
}
-static long xenbus_backend_ioctl(struct file *file, unsigned int cmd, unsigned long data)
+static long xenbus_alloc(domid_t domid)
+{
+ struct evtchn_alloc_unbound arg;
+ int err = -EEXIST;
+
+ xs_suspend();
+
+ /* If xenstored_ready is nonzero, that means we have already talked to
+ * xenstore and set up watches. These watches will be restored by
+ * xs_resume, but that requires communication over the port established
+ * below that is not visible to anyone until the ioctl returns.
+ *
+ * This can be resolved by splitting the ioctl into two parts
+ * (postponing the resume until xenstored is active) but this is
+ * unnecessarily complex for the intended use where xenstored is only
+ * started once - so return -EEXIST if it's already running.
+ */
+ if (xenstored_ready)
+ goto out_err;
+
+ gnttab_grant_foreign_access_ref(GNTTAB_RESERVED_XENSTORE, domid,
+ virt_to_mfn(xen_store_interface), 0 /* writable */);
+
+ arg.dom = DOMID_SELF;
+ arg.remote_dom = domid;
+
+ err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound, &arg);
+ if (err)
+ goto out_err;
+
+ if (xen_store_evtchn > 0)
+ xb_deinit_comms();
+
+ xen_store_evtchn = arg.port;
+
+ xs_resume();
+
+ return arg.port;
+
+ out_err:
+ xs_suspend_cancel();
+ return err;
+}
+
+static long xenbus_backend_ioctl(struct file *file, unsigned int cmd,
+ unsigned long data)
{
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
switch (cmd) {
- case IOCTL_XENBUS_BACKEND_EVTCHN:
- if (xen_store_evtchn > 0)
- return xen_store_evtchn;
- return -ENODEV;
-
- default:
- return -ENOTTY;
+ case IOCTL_XENBUS_BACKEND_EVTCHN:
+ if (xen_store_evtchn > 0)
+ return xen_store_evtchn;
+ return -ENODEV;
+ case IOCTL_XENBUS_BACKEND_SETUP:
+ return xenbus_alloc(data);
+ default:
+ return -ENOTTY;
}
}
@@ -56,7 +108,7 @@ static int xenbus_backend_mmap(struct file *file, struct vm_area_struct *vma)
return 0;
}
-const struct file_operations xenbus_backend_fops = {
+static const struct file_operations xenbus_backend_fops = {
.open = xenbus_backend_open,
.mmap = xenbus_backend_mmap,
.unlocked_ioctl = xenbus_backend_ioctl,
@@ -77,7 +129,7 @@ static int __init xenbus_backend_init(void)
err = misc_register(&xenbus_backend_dev);
if (err)
- printk(KERN_ERR "Could not register xenbus backend device\n");
+ pr_err("Could not register xenbus backend device\n");
return err;
}
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index 89f76252a16..85534ea6355 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -35,6 +35,8 @@
* Turned xenfs into a loadable module.
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/uio.h>
@@ -458,7 +460,7 @@ static ssize_t xenbus_file_write(struct file *filp,
goto out;
/* Can't write a xenbus message larger we can buffer */
- if ((len + u->len) > sizeof(u->u.buffer)) {
+ if (len > sizeof(u->u.buffer) - u->len) {
/* On error, dump existing buffer */
u->len = 0;
rc = -EINVAL;
@@ -616,7 +618,7 @@ static int __init xenbus_init(void)
err = misc_register(&xenbus_dev);
if (err)
- printk(KERN_ERR "Could not register xenbus frontend device\n");
+ pr_err("Could not register xenbus frontend device\n");
return err;
}
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 3864967202b..3c0a74b3e9b 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -30,6 +30,8 @@
* IN THE SOFTWARE.
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#define DPRINTK(fmt, args...) \
pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
__func__, __LINE__, ##args)
@@ -69,6 +71,9 @@ EXPORT_SYMBOL_GPL(xen_store_evtchn);
struct xenstore_domain_interface *xen_store_interface;
EXPORT_SYMBOL_GPL(xen_store_interface);
+enum xenstore_init xen_store_domain_type;
+EXPORT_SYMBOL_GPL(xen_store_domain_type);
+
static unsigned long xen_store_mfn;
static BLOCKING_NOTIFIER_HEAD(xenstore_chain);
@@ -257,11 +262,12 @@ int xenbus_dev_remove(struct device *_dev)
DPRINTK("%s", dev->nodename);
free_otherend_watch(dev);
- free_otherend_details(dev);
if (drv->remove)
drv->remove(dev);
+ free_otherend_details(dev);
+
xenbus_switch_state(dev, XenbusStateClosed);
return 0;
}
@@ -276,15 +282,15 @@ void xenbus_dev_shutdown(struct device *_dev)
get_device(&dev->dev);
if (dev->state != XenbusStateConnected) {
- printk(KERN_INFO "%s: %s: %s != Connected, skipping\n", __func__,
- dev->nodename, xenbus_strstate(dev->state));
+ pr_info("%s: %s: %s != Connected, skipping\n",
+ __func__, dev->nodename, xenbus_strstate(dev->state));
goto out;
}
xenbus_switch_state(dev, XenbusStateClosing);
timeout = wait_for_completion_timeout(&dev->down, timeout);
if (!timeout)
- printk(KERN_INFO "%s: %s timeout closing device\n",
- __func__, dev->nodename);
+ pr_info("%s: %s timeout closing device\n",
+ __func__, dev->nodename);
out:
put_device(&dev->dev);
}
@@ -323,8 +329,8 @@ static int cmp_dev(struct device *dev, void *data)
return 0;
}
-struct xenbus_device *xenbus_device_find(const char *nodename,
- struct bus_type *bus)
+static struct xenbus_device *xenbus_device_find(const char *nodename,
+ struct bus_type *bus)
{
struct xb_find_info info = { .dev = NULL, .nodename = nodename };
@@ -378,12 +384,14 @@ static ssize_t nodename_show(struct device *dev,
{
return sprintf(buf, "%s\n", to_xenbus_device(dev)->nodename);
}
+static DEVICE_ATTR_RO(nodename);
static ssize_t devtype_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%s\n", to_xenbus_device(dev)->devicetype);
}
+static DEVICE_ATTR_RO(devtype);
static ssize_t modalias_show(struct device *dev,
struct device_attribute *attr, char *buf)
@@ -391,14 +399,24 @@ static ssize_t modalias_show(struct device *dev,
return sprintf(buf, "%s:%s\n", dev->bus->name,
to_xenbus_device(dev)->devicetype);
}
+static DEVICE_ATTR_RO(modalias);
-struct device_attribute xenbus_dev_attrs[] = {
- __ATTR_RO(nodename),
- __ATTR_RO(devtype),
- __ATTR_RO(modalias),
- __ATTR_NULL
+static struct attribute *xenbus_dev_attrs[] = {
+ &dev_attr_nodename.attr,
+ &dev_attr_devtype.attr,
+ &dev_attr_modalias.attr,
+ NULL,
};
-EXPORT_SYMBOL_GPL(xenbus_dev_attrs);
+
+static const struct attribute_group xenbus_dev_group = {
+ .attrs = xenbus_dev_attrs,
+};
+
+const struct attribute_group *xenbus_dev_groups[] = {
+ &xenbus_dev_group,
+ NULL,
+};
+EXPORT_SYMBOL_GPL(xenbus_dev_groups);
int xenbus_probe_node(struct xen_bus_type *bus,
const char *type,
@@ -443,7 +461,7 @@ int xenbus_probe_node(struct xen_bus_type *bus,
if (err)
goto fail;
- dev_set_name(&xendev->dev, devname);
+ dev_set_name(&xendev->dev, "%s", devname);
/* Register with generic device framework. */
err = device_register(&xendev->dev);
@@ -575,8 +593,7 @@ int xenbus_dev_suspend(struct device *dev)
if (drv->suspend)
err = drv->suspend(xdev);
if (err)
- printk(KERN_WARNING
- "xenbus: suspend %s failed: %i\n", dev_name(dev), err);
+ pr_warn("suspend %s failed: %i\n", dev_name(dev), err);
return 0;
}
EXPORT_SYMBOL_GPL(xenbus_dev_suspend);
@@ -595,9 +612,8 @@ int xenbus_dev_resume(struct device *dev)
drv = to_xenbus_driver(dev->driver);
err = talk_to_otherend(xdev);
if (err) {
- printk(KERN_WARNING
- "xenbus: resume (talk_to_otherend) %s failed: %i\n",
- dev_name(dev), err);
+ pr_warn("resume (talk_to_otherend) %s failed: %i\n",
+ dev_name(dev), err);
return err;
}
@@ -606,18 +622,15 @@ int xenbus_dev_resume(struct device *dev)
if (drv->resume) {
err = drv->resume(xdev);
if (err) {
- printk(KERN_WARNING
- "xenbus: resume %s failed: %i\n",
- dev_name(dev), err);
+ pr_warn("resume %s failed: %i\n", dev_name(dev), err);
return err;
}
}
err = watch_otherend(xdev);
if (err) {
- printk(KERN_WARNING
- "xenbus_probe: resume (watch_otherend) %s failed: "
- "%d.\n", dev_name(dev), err);
+ pr_warn("resume (watch_otherend) %s failed: %d.\n",
+ dev_name(dev), err);
return err;
}
@@ -721,14 +734,38 @@ static int __init xenstored_local_init(void)
static int __init xenbus_init(void)
{
int err = 0;
+ uint64_t v = 0;
+ xen_store_domain_type = XS_UNKNOWN;
if (!xen_domain())
return -ENODEV;
xenbus_ring_ops_init();
- if (xen_hvm_domain()) {
- uint64_t v = 0;
+ if (xen_pv_domain())
+ xen_store_domain_type = XS_PV;
+ if (xen_hvm_domain())
+ xen_store_domain_type = XS_HVM;
+ if (xen_hvm_domain() && xen_initial_domain())
+ xen_store_domain_type = XS_LOCAL;
+ if (xen_pv_domain() && !xen_start_info->store_evtchn)
+ xen_store_domain_type = XS_LOCAL;
+ if (xen_pv_domain() && xen_start_info->store_evtchn)
+ xenstored_ready = 1;
+
+ switch (xen_store_domain_type) {
+ case XS_LOCAL:
+ err = xenstored_local_init();
+ if (err)
+ goto out_error;
+ xen_store_interface = mfn_to_virt(xen_store_mfn);
+ break;
+ case XS_PV:
+ xen_store_evtchn = xen_start_info->store_evtchn;
+ xen_store_mfn = xen_start_info->store_mfn;
+ xen_store_interface = mfn_to_virt(xen_store_mfn);
+ break;
+ case XS_HVM:
err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
if (err)
goto out_error;
@@ -737,25 +774,18 @@ static int __init xenbus_init(void)
if (err)
goto out_error;
xen_store_mfn = (unsigned long)v;
- xen_store_interface = ioremap(xen_store_mfn << PAGE_SHIFT, PAGE_SIZE);
- } else {
- xen_store_evtchn = xen_start_info->store_evtchn;
- xen_store_mfn = xen_start_info->store_mfn;
- if (xen_store_evtchn)
- xenstored_ready = 1;
- else {
- err = xenstored_local_init();
- if (err)
- goto out_error;
- }
- xen_store_interface = mfn_to_virt(xen_store_mfn);
+ xen_store_interface =
+ xen_remap(xen_store_mfn << PAGE_SHIFT, PAGE_SIZE);
+ break;
+ default:
+ pr_warn("Xenstore state unknown\n");
+ break;
}
/* Initialize the interface to xenstore. */
err = xs_init();
if (err) {
- printk(KERN_WARNING
- "XENBUS: Error initializing xenstore comms: %i\n", err);
+ pr_warn("Error initializing xenstore comms: %i\n", err);
goto out_error;
}
diff --git a/drivers/xen/xenbus/xenbus_probe.h b/drivers/xen/xenbus/xenbus_probe.h
index bb4f92ed873..1085ec294a1 100644
--- a/drivers/xen/xenbus/xenbus_probe.h
+++ b/drivers/xen/xenbus/xenbus_probe.h
@@ -47,7 +47,14 @@ struct xen_bus_type {
struct bus_type bus;
};
-extern struct device_attribute xenbus_dev_attrs[];
+enum xenstore_init {
+ XS_UNKNOWN,
+ XS_PV,
+ XS_HVM,
+ XS_LOCAL,
+};
+
+extern const struct attribute_group *xenbus_dev_groups[];
extern int xenbus_match(struct device *_dev, struct device_driver *_drv);
extern int xenbus_dev_probe(struct device *_dev);
diff --git a/drivers/xen/xenbus/xenbus_probe_backend.c b/drivers/xen/xenbus/xenbus_probe_backend.c
index 257be37d909..5125dce11a6 100644
--- a/drivers/xen/xenbus/xenbus_probe_backend.c
+++ b/drivers/xen/xenbus/xenbus_probe_backend.c
@@ -31,9 +31,11 @@
* IN THE SOFTWARE.
*/
-#define DPRINTK(fmt, args...) \
- pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
- __func__, __LINE__, ##args)
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#define DPRINTK(fmt, ...) \
+ pr_debug("(%s:%d) " fmt "\n", \
+ __func__, __LINE__, ##__VA_ARGS__)
#include <linux/kernel.h>
#include <linux/err.h>
@@ -198,7 +200,7 @@ static struct xen_bus_type xenbus_backend = {
.probe = xenbus_dev_probe,
.remove = xenbus_dev_remove,
.shutdown = xenbus_dev_shutdown,
- .dev_attrs = xenbus_dev_attrs,
+ .dev_groups = xenbus_dev_groups,
},
};
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index 9c57819df51..cb385c10d2b 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -1,6 +1,8 @@
-#define DPRINTK(fmt, args...) \
- pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
- __func__, __LINE__, ##args)
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#define DPRINTK(fmt, ...) \
+ pr_debug("(%s:%d) " fmt "\n", \
+ __func__, __LINE__, ##__VA_ARGS__)
#include <linux/kernel.h>
#include <linux/err.h>
@@ -21,6 +23,7 @@
#include <xen/xenbus.h>
#include <xen/events.h>
#include <xen/page.h>
+#include <xen/xen.h>
#include <xen/platform_pci.h>
@@ -28,18 +31,20 @@
#include "xenbus_probe.h"
+static struct workqueue_struct *xenbus_frontend_wq;
+
/* device/<type>/<id> => <type>-<id> */
static int frontend_bus_id(char bus_id[XEN_BUS_ID_SIZE], const char *nodename)
{
nodename = strchr(nodename, '/');
if (!nodename || strlen(nodename + 1) >= XEN_BUS_ID_SIZE) {
- printk(KERN_WARNING "XENBUS: bad frontend %s\n", nodename);
+ pr_warn("bad frontend %s\n", nodename);
return -EINVAL;
}
strlcpy(bus_id, nodename + 1, XEN_BUS_ID_SIZE);
if (!strchr(bus_id, '/')) {
- printk(KERN_WARNING "XENBUS: bus_id %s no slash\n", bus_id);
+ pr_warn("bus_id %s no slash\n", bus_id);
return -EINVAL;
}
*strchr(bus_id, '/') = '-';
@@ -53,6 +58,12 @@ static int xenbus_probe_frontend(struct xen_bus_type *bus, const char *type,
char *nodename;
int err;
+ /* ignore console/0 */
+ if (!strncmp(type, "console", 7) && !strncmp(name, "0", 1)) {
+ DPRINTK("Ignoring buggy device entry console/0");
+ return 0;
+ }
+
nodename = kasprintf(GFP_KERNEL, "%s/%s/%s", bus->root, type, name);
if (!nodename)
return -ENOMEM;
@@ -82,9 +93,49 @@ static void backend_changed(struct xenbus_watch *watch,
xenbus_otherend_changed(watch, vec, len, 1);
}
+static void xenbus_frontend_delayed_resume(struct work_struct *w)
+{
+ struct xenbus_device *xdev = container_of(w, struct xenbus_device, work);
+
+ xenbus_dev_resume(&xdev->dev);
+}
+
+static int xenbus_frontend_dev_resume(struct device *dev)
+{
+ /*
+ * If xenstored is running in this domain, we cannot access the backend
+ * state at the moment, so we need to defer xenbus_dev_resume
+ */
+ if (xen_store_domain_type == XS_LOCAL) {
+ struct xenbus_device *xdev = to_xenbus_device(dev);
+
+ if (!xenbus_frontend_wq) {
+ pr_err("%s: no workqueue to process delayed resume\n",
+ xdev->nodename);
+ return -EFAULT;
+ }
+
+ queue_work(xenbus_frontend_wq, &xdev->work);
+
+ return 0;
+ }
+
+ return xenbus_dev_resume(dev);
+}
+
+static int xenbus_frontend_dev_probe(struct device *dev)
+{
+ if (xen_store_domain_type == XS_LOCAL) {
+ struct xenbus_device *xdev = to_xenbus_device(dev);
+ INIT_WORK(&xdev->work, xenbus_frontend_delayed_resume);
+ }
+
+ return xenbus_dev_probe(dev);
+}
+
static const struct dev_pm_ops xenbus_pm_ops = {
.suspend = xenbus_dev_suspend,
- .resume = xenbus_dev_resume,
+ .resume = xenbus_frontend_dev_resume,
.freeze = xenbus_dev_suspend,
.thaw = xenbus_dev_cancel,
.restore = xenbus_dev_resume,
@@ -100,10 +151,10 @@ static struct xen_bus_type xenbus_frontend = {
.name = "xen",
.match = xenbus_match,
.uevent = xenbus_uevent_frontend,
- .probe = xenbus_dev_probe,
+ .probe = xenbus_frontend_dev_probe,
.remove = xenbus_dev_remove,
.shutdown = xenbus_dev_shutdown,
- .dev_attrs = xenbus_dev_attrs,
+ .dev_groups = xenbus_dev_groups,
.pm = &xenbus_pm_ops,
},
@@ -129,7 +180,7 @@ static int read_backend_details(struct xenbus_device *xendev)
return xenbus_read_otherend_details(xendev, "backend-id", "backend");
}
-static int is_device_connecting(struct device *dev, void *data)
+static int is_device_connecting(struct device *dev, void *data, bool ignore_nonessential)
{
struct xenbus_device *xendev = to_xenbus_device(dev);
struct device_driver *drv = data;
@@ -146,16 +197,41 @@ static int is_device_connecting(struct device *dev, void *data)
if (drv && (dev->driver != drv))
return 0;
+ if (ignore_nonessential) {
+ /* With older QEMU, for PVonHVM guests the guest config files
+ * could contain: vfb = [ 'vnc=1, vnclisten=0.0.0.0']
+ * which is nonsensical as there is no PV FB (there can be
+ * a PVKB) running as HVM guest. */
+
+ if ((strncmp(xendev->nodename, "device/vkbd", 11) == 0))
+ return 0;
+
+ if ((strncmp(xendev->nodename, "device/vfb", 10) == 0))
+ return 0;
+ }
xendrv = to_xenbus_driver(dev->driver);
return (xendev->state < XenbusStateConnected ||
(xendev->state == XenbusStateConnected &&
xendrv->is_ready && !xendrv->is_ready(xendev)));
}
+static int essential_device_connecting(struct device *dev, void *data)
+{
+ return is_device_connecting(dev, data, true /* ignore PV[KBB+FB] */);
+}
+static int non_essential_device_connecting(struct device *dev, void *data)
+{
+ return is_device_connecting(dev, data, false);
+}
-static int exists_connecting_device(struct device_driver *drv)
+static int exists_essential_connecting_device(struct device_driver *drv)
{
return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
- is_device_connecting);
+ essential_device_connecting);
+}
+static int exists_non_essential_connecting_device(struct device_driver *drv)
+{
+ return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
+ non_essential_device_connecting);
}
static int print_device_status(struct device *dev, void *data)
@@ -169,15 +245,13 @@ static int print_device_status(struct device *dev, void *data)
if (!dev->driver) {
/* Information only: is this too noisy? */
- printk(KERN_INFO "XENBUS: Device with no driver: %s\n",
- xendev->nodename);
+ pr_info("Device with no driver: %s\n", xendev->nodename);
} else if (xendev->state < XenbusStateConnected) {
enum xenbus_state rstate = XenbusStateUnknown;
if (xendev->otherend)
rstate = xenbus_read_driver_state(xendev->otherend);
- printk(KERN_WARNING "XENBUS: Timeout connecting "
- "to device: %s (local state %d, remote state %d)\n",
- xendev->nodename, xendev->state, rstate);
+ pr_warn("Timeout connecting to device: %s (local state %d, remote state %d)\n",
+ xendev->nodename, xendev->state, rstate);
}
return 0;
@@ -186,6 +260,24 @@ static int print_device_status(struct device *dev, void *data)
/* We only wait for device setup after most initcalls have run. */
static int ready_to_wait_for_devices;
+static bool wait_loop(unsigned long start, unsigned int max_delay,
+ unsigned int *seconds_waited)
+{
+ if (time_after(jiffies, start + (*seconds_waited+5)*HZ)) {
+ if (!*seconds_waited)
+ pr_warn("Waiting for devices to initialise: ");
+ *seconds_waited += 5;
+ pr_cont("%us...", max_delay - *seconds_waited);
+ if (*seconds_waited == max_delay) {
+ pr_cont("\n");
+ return true;
+ }
+ }
+
+ schedule_timeout_interruptible(HZ/10);
+
+ return false;
+}
/*
* On a 5-minute timeout, wait for all devices currently configured. We need
* to do this to guarantee that the filesystems and / or network devices
@@ -209,19 +301,14 @@ static void wait_for_devices(struct xenbus_driver *xendrv)
if (!ready_to_wait_for_devices || !xen_domain())
return;
- while (exists_connecting_device(drv)) {
- if (time_after(jiffies, start + (seconds_waited+5)*HZ)) {
- if (!seconds_waited)
- printk(KERN_WARNING "XENBUS: Waiting for "
- "devices to initialise: ");
- seconds_waited += 5;
- printk("%us...", 300 - seconds_waited);
- if (seconds_waited == 300)
- break;
- }
+ while (exists_non_essential_connecting_device(drv))
+ if (wait_loop(start, 30, &seconds_waited))
+ break;
- schedule_timeout_interruptible(HZ/10);
- }
+ /* Skips PVKB and PVFB check.*/
+ while (exists_essential_connecting_device(drv))
+ if (wait_loop(start, 270, &seconds_waited))
+ break;
if (seconds_waited)
printk("\n");
@@ -265,7 +352,7 @@ static void xenbus_reset_wait_for_backend(char *be, int expected)
timeout = wait_event_interruptible_timeout(backend_state_wq,
backend_state == expected, 5 * HZ);
if (timeout <= 0)
- printk(KERN_INFO "XENBUS: backend %s timed out.\n", be);
+ pr_info("backend %s timed out\n", be);
}
/*
@@ -288,7 +375,7 @@ static void xenbus_reset_frontend(char *fe, char *be, int be_state)
be_watch.callback = xenbus_reset_backend_state_changed;
backend_state = XenbusStateUnknown;
- printk(KERN_INFO "XENBUS: triggering reconnect on %s\n", be);
+ pr_info("triggering reconnect on %s\n", be);
register_xenbus_watch(&be_watch);
/* fall through to forward backend to state XenbusStateInitialising */
@@ -307,7 +394,7 @@ static void xenbus_reset_frontend(char *fe, char *be, int be_state)
}
unregister_xenbus_watch(&be_watch);
- printk(KERN_INFO "XENBUS: reconnect done on %s\n", be);
+ pr_info("reconnect done on %s\n", be);
kfree(be_watch.node);
}
@@ -396,6 +483,12 @@ static int __init xenbus_probe_frontend_init(void)
register_xenstore_notifier(&xenstore_notifier);
+ if (xen_store_domain_type == XS_LOCAL) {
+ xenbus_frontend_wq = create_workqueue("xenbus_frontend");
+ if (!xenbus_frontend_wq)
+ pr_warn("create xenbus frontend workqueue failed, S3 resume is likely to fail\n");
+ }
+
return 0;
}
subsys_initcall(xenbus_probe_frontend_init);
@@ -403,7 +496,7 @@ subsys_initcall(xenbus_probe_frontend_init);
#ifndef MODULE
static int __init boot_wait_for_devices(void)
{
- if (xen_hvm_domain() && !xen_platform_pci_unplug)
+ if (!xen_has_pv_devices())
return -ENODEV;
ready_to_wait_for_devices = 1;
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index d1c217b23a4..ba804f3d827 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -31,6 +31,8 @@
* IN THE SOFTWARE.
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <linux/unistd.h>
#include <linux/errno.h>
#include <linux/types.h>
@@ -44,9 +46,11 @@
#include <linux/rwsem.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <asm/xen/hypervisor.h>
#include <xen/xenbus.h>
#include <xen/xen.h>
#include "xenbus_comms.h"
+#include "xenbus_probe.h"
struct xs_stored_msg {
struct list_head list;
@@ -128,15 +132,37 @@ static int get_error(const char *errorstring)
for (i = 0; strcmp(errorstring, xsd_errors[i].errstring) != 0; i++) {
if (i == ARRAY_SIZE(xsd_errors) - 1) {
- printk(KERN_WARNING
- "XENBUS xen store gave: unknown error %s",
- errorstring);
+ pr_warn("xen store gave: unknown error %s\n",
+ errorstring);
return EINVAL;
}
}
return xsd_errors[i].errnum;
}
+static bool xenbus_ok(void)
+{
+ switch (xen_store_domain_type) {
+ case XS_LOCAL:
+ switch (system_state) {
+ case SYSTEM_POWER_OFF:
+ case SYSTEM_RESTART:
+ case SYSTEM_HALT:
+ return false;
+ default:
+ break;
+ }
+ return true;
+ case XS_PV:
+ case XS_HVM:
+ /* FIXME: Could check that the remote domain is alive,
+ * but it is normally initial domain. */
+ return true;
+ default:
+ break;
+ }
+ return false;
+}
static void *read_reply(enum xsd_sockmsg_type *type, unsigned int *len)
{
struct xs_stored_msg *msg;
@@ -146,9 +172,20 @@ static void *read_reply(enum xsd_sockmsg_type *type, unsigned int *len)
while (list_empty(&xs_state.reply_list)) {
spin_unlock(&xs_state.reply_lock);
- /* XXX FIXME: Avoid synchronous wait for response here. */
- wait_event(xs_state.reply_waitq,
- !list_empty(&xs_state.reply_list));
+ if (xenbus_ok())
+ /* XXX FIXME: Avoid synchronous wait for response here. */
+ wait_event_timeout(xs_state.reply_waitq,
+ !list_empty(&xs_state.reply_list),
+ msecs_to_jiffies(500));
+ else {
+ /*
+ * If we are in the process of being shut-down there is
+ * no point of trying to contact XenBus - it is either
+ * killed (xenstored application) or the other domain
+ * has been killed or is unreachable.
+ */
+ return ERR_PTR(-EIO);
+ }
spin_lock(&xs_state.reply_lock);
}
@@ -213,6 +250,9 @@ void *xenbus_dev_request_and_reply(struct xsd_sockmsg *msg)
mutex_unlock(&xs_state.request_mutex);
+ if (IS_ERR(ret))
+ return ret;
+
if ((msg->type == XS_TRANSACTION_END) ||
((req_msg.type == XS_TRANSACTION_START) &&
(msg->type == XS_ERROR)))
@@ -271,10 +311,8 @@ static void *xs_talkv(struct xenbus_transaction t,
}
if (msg.type != type) {
- if (printk_ratelimit())
- printk(KERN_WARNING
- "XENBUS unexpected type [%d], expected [%d]\n",
- msg.type, type);
+ pr_warn_ratelimited("unexpected type [%d], expected [%d]\n",
+ msg.type, type);
kfree(ret);
return ERR_PTR(-EINVAL);
}
@@ -617,6 +655,45 @@ static struct xenbus_watch *find_watch(const char *token)
return NULL;
}
+/*
+ * Certain older XenBus toolstack cannot handle reading values that are
+ * not populated. Some Xen 3.4 installation are incapable of doing this
+ * so if we are running on anything older than 4 do not attempt to read
+ * control/platform-feature-xs_reset_watches.
+ */
+static bool xen_strict_xenbus_quirk(void)
+{
+#ifdef CONFIG_X86
+ uint32_t eax, ebx, ecx, edx, base;
+
+ base = xen_cpuid_base();
+ cpuid(base + 1, &eax, &ebx, &ecx, &edx);
+
+ if ((eax >> 16) < 4)
+ return true;
+#endif
+ return false;
+
+}
+static void xs_reset_watches(void)
+{
+ int err, supported = 0;
+
+ if (!xen_hvm_domain() || xen_initial_domain())
+ return;
+
+ if (xen_strict_xenbus_quirk())
+ return;
+
+ err = xenbus_scanf(XBT_NIL, "control",
+ "platform-feature-xs_reset_watches", "%d", &supported);
+ if (err != 1 || !supported)
+ return;
+
+ err = xs_error(xs_single(XBT_NIL, XS_RESET_WATCHES, "", NULL));
+ if (err && err != -EEXIST)
+ pr_warn("xs_reset_watches failed: %d\n", err);
+}
/* Register callback to watch this node. */
int register_xenbus_watch(struct xenbus_watch *watch)
@@ -665,9 +742,7 @@ void unregister_xenbus_watch(struct xenbus_watch *watch)
err = xs_unwatch(watch->node, token);
if (err)
- printk(KERN_WARNING
- "XENBUS Failed to release watch %s: %i\n",
- watch->node, err);
+ pr_warn("Failed to release watch %s: %i\n", watch->node, err);
up_read(&xs_state.watch_mutex);
@@ -861,8 +936,7 @@ static int xenbus_thread(void *unused)
for (;;) {
err = process_msg();
if (err)
- printk(KERN_WARNING "XENBUS error %d while reading "
- "message\n", err);
+ pr_warn("error %d while reading message\n", err);
if (kthread_should_stop())
break;
}
@@ -900,5 +974,8 @@ int xs_init(void)
if (IS_ERR(task))
return PTR_ERR(task);
+ /* shutdown watches for kexec boot */
+ xs_reset_watches();
+
return 0;
}