diff options
Diffstat (limited to 'drivers/tty/hvc/hvc_xen.c')
| -rw-r--r-- | drivers/tty/hvc/hvc_xen.c | 465 |
1 files changed, 422 insertions, 43 deletions
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c index a1b0a75c3eae..83d5c88e7165 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; - 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()) |