diff options
Diffstat (limited to 'drivers/xen/xenbus/xenbus_probe_frontend.c')
| -rw-r--r-- | drivers/xen/xenbus/xenbus_probe_frontend.c | 157 |
1 files changed, 125 insertions, 32 deletions
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; |