Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / hv / hv.c
diff --git a/kernel/drivers/hv/hv.c b/kernel/drivers/hv/hv.c
new file mode 100644 (file)
index 0000000..d3943bc
--- /dev/null
@@ -0,0 +1,535 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/hyperv.h>
+#include <linux/version.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <asm/hyperv.h>
+#include <asm/mshyperv.h>
+#include "hyperv_vmbus.h"
+
+/* The one and only */
+struct hv_context hv_context = {
+       .synic_initialized      = false,
+       .hypercall_page         = NULL,
+};
+
+#define HV_TIMER_FREQUENCY (10 * 1000 * 1000) /* 100ns period */
+#define HV_MAX_MAX_DELTA_TICKS 0xffffffff
+#define HV_MIN_DELTA_TICKS 1
+
+/*
+ * query_hypervisor_info - Get version info of the windows hypervisor
+ */
+unsigned int host_info_eax;
+unsigned int host_info_ebx;
+unsigned int host_info_ecx;
+unsigned int host_info_edx;
+
+static int query_hypervisor_info(void)
+{
+       unsigned int eax;
+       unsigned int ebx;
+       unsigned int ecx;
+       unsigned int edx;
+       unsigned int max_leaf;
+       unsigned int op;
+
+       /*
+       * Its assumed that this is called after confirming that Viridian
+       * is present. Query id and revision.
+       */
+       eax = 0;
+       ebx = 0;
+       ecx = 0;
+       edx = 0;
+       op = HVCPUID_VENDOR_MAXFUNCTION;
+       cpuid(op, &eax, &ebx, &ecx, &edx);
+
+       max_leaf = eax;
+
+       if (max_leaf >= HVCPUID_VERSION) {
+               eax = 0;
+               ebx = 0;
+               ecx = 0;
+               edx = 0;
+               op = HVCPUID_VERSION;
+               cpuid(op, &eax, &ebx, &ecx, &edx);
+               host_info_eax = eax;
+               host_info_ebx = ebx;
+               host_info_ecx = ecx;
+               host_info_edx = edx;
+       }
+       return max_leaf;
+}
+
+/*
+ * do_hypercall- Invoke the specified hypercall
+ */
+static u64 do_hypercall(u64 control, void *input, void *output)
+{
+#ifdef CONFIG_X86_64
+       u64 hv_status = 0;
+       u64 input_address = (input) ? virt_to_phys(input) : 0;
+       u64 output_address = (output) ? virt_to_phys(output) : 0;
+       void *hypercall_page = hv_context.hypercall_page;
+
+       __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8");
+       __asm__ __volatile__("call *%3" : "=a" (hv_status) :
+                            "c" (control), "d" (input_address),
+                            "m" (hypercall_page));
+
+       return hv_status;
+
+#else
+
+       u32 control_hi = control >> 32;
+       u32 control_lo = control & 0xFFFFFFFF;
+       u32 hv_status_hi = 1;
+       u32 hv_status_lo = 1;
+       u64 input_address = (input) ? virt_to_phys(input) : 0;
+       u32 input_address_hi = input_address >> 32;
+       u32 input_address_lo = input_address & 0xFFFFFFFF;
+       u64 output_address = (output) ? virt_to_phys(output) : 0;
+       u32 output_address_hi = output_address >> 32;
+       u32 output_address_lo = output_address & 0xFFFFFFFF;
+       void *hypercall_page = hv_context.hypercall_page;
+
+       __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi),
+                             "=a"(hv_status_lo) : "d" (control_hi),
+                             "a" (control_lo), "b" (input_address_hi),
+                             "c" (input_address_lo), "D"(output_address_hi),
+                             "S"(output_address_lo), "m" (hypercall_page));
+
+       return hv_status_lo | ((u64)hv_status_hi << 32);
+#endif /* !x86_64 */
+}
+
+/*
+ * hv_init - Main initialization routine.
+ *
+ * This routine must be called before any other routines in here are called
+ */
+int hv_init(void)
+{
+       int max_leaf;
+       union hv_x64_msr_hypercall_contents hypercall_msr;
+       void *virtaddr = NULL;
+
+       memset(hv_context.synic_event_page, 0, sizeof(void *) * NR_CPUS);
+       memset(hv_context.synic_message_page, 0,
+              sizeof(void *) * NR_CPUS);
+       memset(hv_context.post_msg_page, 0,
+              sizeof(void *) * NR_CPUS);
+       memset(hv_context.vp_index, 0,
+              sizeof(int) * NR_CPUS);
+       memset(hv_context.event_dpc, 0,
+              sizeof(void *) * NR_CPUS);
+       memset(hv_context.clk_evt, 0,
+              sizeof(void *) * NR_CPUS);
+
+       max_leaf = query_hypervisor_info();
+
+       /*
+        * Write our OS ID.
+        */
+       hv_context.guestid = generate_guest_id(0, LINUX_VERSION_CODE, 0);
+       wrmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid);
+
+       /* See if the hypercall page is already set */
+       rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+       virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
+
+       if (!virtaddr)
+               goto cleanup;
+
+       hypercall_msr.enable = 1;
+
+       hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr);
+       wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+       /* Confirm that hypercall page did get setup. */
+       hypercall_msr.as_uint64 = 0;
+       rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+       if (!hypercall_msr.enable)
+               goto cleanup;
+
+       hv_context.hypercall_page = virtaddr;
+
+       return 0;
+
+cleanup:
+       if (virtaddr) {
+               if (hypercall_msr.enable) {
+                       hypercall_msr.as_uint64 = 0;
+                       wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+               }
+
+               vfree(virtaddr);
+       }
+
+       return -ENOTSUPP;
+}
+
+/*
+ * hv_cleanup - Cleanup routine.
+ *
+ * This routine is called normally during driver unloading or exiting.
+ */
+void hv_cleanup(void)
+{
+       union hv_x64_msr_hypercall_contents hypercall_msr;
+
+       /* Reset our OS id */
+       wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
+
+       if (hv_context.hypercall_page) {
+               hypercall_msr.as_uint64 = 0;
+               wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+               vfree(hv_context.hypercall_page);
+               hv_context.hypercall_page = NULL;
+       }
+}
+
+/*
+ * hv_post_message - Post a message using the hypervisor message IPC.
+ *
+ * This involves a hypercall.
+ */
+int hv_post_message(union hv_connection_id connection_id,
+                 enum hv_message_type message_type,
+                 void *payload, size_t payload_size)
+{
+
+       struct hv_input_post_message *aligned_msg;
+       u16 status;
+
+       if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
+               return -EMSGSIZE;
+
+       aligned_msg = (struct hv_input_post_message *)
+                       hv_context.post_msg_page[get_cpu()];
+
+       aligned_msg->connectionid = connection_id;
+       aligned_msg->reserved = 0;
+       aligned_msg->message_type = message_type;
+       aligned_msg->payload_size = payload_size;
+       memcpy((void *)aligned_msg->payload, payload, payload_size);
+
+       status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL)
+               & 0xFFFF;
+
+       put_cpu();
+       return status;
+}
+
+
+/*
+ * hv_signal_event -
+ * Signal an event on the specified connection using the hypervisor event IPC.
+ *
+ * This involves a hypercall.
+ */
+u16 hv_signal_event(void *con_id)
+{
+       u16 status;
+
+       status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF);
+
+       return status;
+}
+
+static int hv_ce_set_next_event(unsigned long delta,
+                               struct clock_event_device *evt)
+{
+       cycle_t current_tick;
+
+       WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT);
+
+       rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick);
+       current_tick += delta;
+       wrmsrl(HV_X64_MSR_STIMER0_COUNT, current_tick);
+       return 0;
+}
+
+static void hv_ce_setmode(enum clock_event_mode mode,
+                         struct clock_event_device *evt)
+{
+       union hv_timer_config timer_cfg;
+
+       switch (mode) {
+       case CLOCK_EVT_MODE_PERIODIC:
+               /* unsupported */
+               break;
+
+       case CLOCK_EVT_MODE_ONESHOT:
+               timer_cfg.enable = 1;
+               timer_cfg.auto_enable = 1;
+               timer_cfg.sintx = VMBUS_MESSAGE_SINT;
+               wrmsrl(HV_X64_MSR_STIMER0_CONFIG, timer_cfg.as_uint64);
+               break;
+
+       case CLOCK_EVT_MODE_UNUSED:
+       case CLOCK_EVT_MODE_SHUTDOWN:
+               wrmsrl(HV_X64_MSR_STIMER0_COUNT, 0);
+               wrmsrl(HV_X64_MSR_STIMER0_CONFIG, 0);
+               break;
+       case CLOCK_EVT_MODE_RESUME:
+               break;
+       }
+}
+
+static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu)
+{
+       dev->name = "Hyper-V clockevent";
+       dev->features = CLOCK_EVT_FEAT_ONESHOT;
+       dev->cpumask = cpumask_of(cpu);
+       dev->rating = 1000;
+       /*
+        * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will
+        * result in clockevents_config_and_register() taking additional
+        * references to the hv_vmbus module making it impossible to unload.
+        */
+
+       dev->set_mode = hv_ce_setmode;
+       dev->set_next_event = hv_ce_set_next_event;
+}
+
+
+int hv_synic_alloc(void)
+{
+       size_t size = sizeof(struct tasklet_struct);
+       size_t ced_size = sizeof(struct clock_event_device);
+       int cpu;
+
+       for_each_online_cpu(cpu) {
+               hv_context.event_dpc[cpu] = kmalloc(size, GFP_ATOMIC);
+               if (hv_context.event_dpc[cpu] == NULL) {
+                       pr_err("Unable to allocate event dpc\n");
+                       goto err;
+               }
+               tasklet_init(hv_context.event_dpc[cpu], vmbus_on_event, cpu);
+
+               hv_context.clk_evt[cpu] = kzalloc(ced_size, GFP_ATOMIC);
+               if (hv_context.clk_evt[cpu] == NULL) {
+                       pr_err("Unable to allocate clock event device\n");
+                       goto err;
+               }
+               hv_init_clockevent_device(hv_context.clk_evt[cpu], cpu);
+
+               hv_context.synic_message_page[cpu] =
+                       (void *)get_zeroed_page(GFP_ATOMIC);
+
+               if (hv_context.synic_message_page[cpu] == NULL) {
+                       pr_err("Unable to allocate SYNIC message page\n");
+                       goto err;
+               }
+
+               hv_context.synic_event_page[cpu] =
+                       (void *)get_zeroed_page(GFP_ATOMIC);
+
+               if (hv_context.synic_event_page[cpu] == NULL) {
+                       pr_err("Unable to allocate SYNIC event page\n");
+                       goto err;
+               }
+
+               hv_context.post_msg_page[cpu] =
+                       (void *)get_zeroed_page(GFP_ATOMIC);
+
+               if (hv_context.post_msg_page[cpu] == NULL) {
+                       pr_err("Unable to allocate post msg page\n");
+                       goto err;
+               }
+       }
+
+       return 0;
+err:
+       return -ENOMEM;
+}
+
+static void hv_synic_free_cpu(int cpu)
+{
+       kfree(hv_context.event_dpc[cpu]);
+       kfree(hv_context.clk_evt[cpu]);
+       if (hv_context.synic_event_page[cpu])
+               free_page((unsigned long)hv_context.synic_event_page[cpu]);
+       if (hv_context.synic_message_page[cpu])
+               free_page((unsigned long)hv_context.synic_message_page[cpu]);
+       if (hv_context.post_msg_page[cpu])
+               free_page((unsigned long)hv_context.post_msg_page[cpu]);
+}
+
+void hv_synic_free(void)
+{
+       int cpu;
+
+       for_each_online_cpu(cpu)
+               hv_synic_free_cpu(cpu);
+}
+
+/*
+ * hv_synic_init - Initialize the Synthethic Interrupt Controller.
+ *
+ * If it is already initialized by another entity (ie x2v shim), we need to
+ * retrieve the initialized message and event pages.  Otherwise, we create and
+ * initialize the message and event pages.
+ */
+void hv_synic_init(void *arg)
+{
+       u64 version;
+       union hv_synic_simp simp;
+       union hv_synic_siefp siefp;
+       union hv_synic_sint shared_sint;
+       union hv_synic_scontrol sctrl;
+       u64 vp_index;
+
+       int cpu = smp_processor_id();
+
+       if (!hv_context.hypercall_page)
+               return;
+
+       /* Check the version */
+       rdmsrl(HV_X64_MSR_SVERSION, version);
+
+       /* Setup the Synic's message page */
+       rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+       simp.simp_enabled = 1;
+       simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu])
+               >> PAGE_SHIFT;
+
+       wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+
+       /* Setup the Synic's event page */
+       rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+       siefp.siefp_enabled = 1;
+       siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu])
+               >> PAGE_SHIFT;
+
+       wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+
+       /* Setup the shared SINT. */
+       rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+       shared_sint.as_uint64 = 0;
+       shared_sint.vector = HYPERVISOR_CALLBACK_VECTOR;
+       shared_sint.masked = false;
+       shared_sint.auto_eoi = true;
+
+       wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+       /* Enable the global synic bit */
+       rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+       sctrl.enable = 1;
+
+       wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+
+       hv_context.synic_initialized = true;
+
+       /*
+        * Setup the mapping between Hyper-V's notion
+        * of cpuid and Linux' notion of cpuid.
+        * This array will be indexed using Linux cpuid.
+        */
+       rdmsrl(HV_X64_MSR_VP_INDEX, vp_index);
+       hv_context.vp_index[cpu] = (u32)vp_index;
+
+       INIT_LIST_HEAD(&hv_context.percpu_list[cpu]);
+
+       /*
+        * Register the per-cpu clockevent source.
+        */
+       if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)
+               clockevents_config_and_register(hv_context.clk_evt[cpu],
+                                               HV_TIMER_FREQUENCY,
+                                               HV_MIN_DELTA_TICKS,
+                                               HV_MAX_MAX_DELTA_TICKS);
+       return;
+}
+
+/*
+ * hv_synic_clockevents_cleanup - Cleanup clockevent devices
+ */
+void hv_synic_clockevents_cleanup(void)
+{
+       int cpu;
+
+       if (!(ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE))
+               return;
+
+       for_each_online_cpu(cpu)
+               clockevents_unbind_device(hv_context.clk_evt[cpu], cpu);
+}
+
+/*
+ * hv_synic_cleanup - Cleanup routine for hv_synic_init().
+ */
+void hv_synic_cleanup(void *arg)
+{
+       union hv_synic_sint shared_sint;
+       union hv_synic_simp simp;
+       union hv_synic_siefp siefp;
+       union hv_synic_scontrol sctrl;
+       int cpu = smp_processor_id();
+
+       if (!hv_context.synic_initialized)
+               return;
+
+       /* Turn off clockevent device */
+       if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)
+               hv_ce_setmode(CLOCK_EVT_MODE_SHUTDOWN,
+                             hv_context.clk_evt[cpu]);
+
+       rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+       shared_sint.masked = 1;
+
+       /* Need to correctly cleanup in the case of SMP!!! */
+       /* Disable the interrupt */
+       wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+       rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+       simp.simp_enabled = 0;
+       simp.base_simp_gpa = 0;
+
+       wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+
+       rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+       siefp.siefp_enabled = 0;
+       siefp.base_siefp_gpa = 0;
+
+       wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+
+       /* Disable the global synic bit */
+       rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+       sctrl.enable = 0;
+       wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+
+       hv_synic_free_cpu(cpu);
+}