diff options
Diffstat (limited to 'drivers/hv/hv.c')
| -rw-r--r-- | drivers/hv/hv.c | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c new file mode 100644 index 00000000000..931b7b03078 --- /dev/null +++ b/drivers/hv/hv.c @@ -0,0 +1,429 @@ +/* + * 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 "hyperv_vmbus.h" + +/* The one and only */ +struct hv_context hv_context = { + .synic_initialized = false, + .hypercall_page = NULL, + .signal_event_param = NULL, + .signal_event_buffer = NULL, +}; + +/* + * query_hypervisor_presence + * - Query the cpuid for presence of windows hypervisor + */ +static int query_hypervisor_presence(void) +{ + unsigned int eax; + unsigned int ebx; + unsigned int ecx; + unsigned int edx; + unsigned int op; + + eax = 0; + ebx = 0; + ecx = 0; + edx = 0; + op = HVCPUID_VERSION_FEATURES; + cpuid(op, &eax, &ebx, &ecx, &edx); + + return ecx & HV_PRESENT_BIT; +} + +/* + * query_hypervisor_info - Get version info of the windows hypervisor + */ +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); + pr_info("Hyper-V Host OS Build:%d-%d.%d-%d-%d.%d\n", + eax, + ebx >> 16, + ebx & 0xFFFF, + ecx, + edx >> 24, + edx & 0xFFFFFF); + } + 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 *) * MAX_NUM_CPUS); + memset(hv_context.synic_message_page, 0, + sizeof(void *) * MAX_NUM_CPUS); + + if (!query_hypervisor_presence()) + goto cleanup; + + max_leaf = query_hypervisor_info(); + + rdmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid); + + if (hv_context.guestid != 0) + goto cleanup; + + /* Write our OS info */ + wrmsrl(HV_X64_MSR_GUEST_OS_ID, HV_LINUX_GUEST_ID); + hv_context.guestid = HV_LINUX_GUEST_ID; + + /* 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; + + /* Setup the global signal event param for the signal event hypercall */ + hv_context.signal_event_buffer = + kmalloc(sizeof(struct hv_input_signal_event_buffer), + GFP_KERNEL); + if (!hv_context.signal_event_buffer) + goto cleanup; + + hv_context.signal_event_param = + (struct hv_input_signal_event *) + (ALIGN((unsigned long) + hv_context.signal_event_buffer, + HV_HYPERCALL_PARAM_ALIGN)); + hv_context.signal_event_param->connectionid.asu32 = 0; + hv_context.signal_event_param->connectionid.u.id = + VMBUS_EVENT_CONNECTION_ID; + hv_context.signal_event_param->flag_number = 0; + hv_context.signal_event_param->rsvdz = 0; + + 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; + + kfree(hv_context.signal_event_buffer); + hv_context.signal_event_buffer = NULL; + hv_context.signal_event_param = NULL; + + 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. + */ +u16 hv_post_message(union hv_connection_id connection_id, + enum hv_message_type message_type, + void *payload, size_t payload_size) +{ + struct aligned_input { + u64 alignment8; + struct hv_input_post_message msg; + }; + + struct hv_input_post_message *aligned_msg; + u16 status; + unsigned long addr; + + if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) + return -EMSGSIZE; + + addr = (unsigned long)kmalloc(sizeof(struct aligned_input), GFP_ATOMIC); + if (!addr) + return -ENOMEM; + + aligned_msg = (struct hv_input_post_message *) + (ALIGN(addr, HV_HYPERCALL_PARAM_ALIGN)); + + aligned_msg->connectionid = connection_id; + 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; + + kfree((void *)addr); + + 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) +{ + u16 status; + + status = do_hypercall(HVCALL_SIGNAL_EVENT, + hv_context.signal_event_param, + NULL) & 0xFFFF; + return status; +} + +/* + * 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 *irqarg) +{ + u64 version; + union hv_synic_simp simp; + union hv_synic_siefp siefp; + union hv_synic_sint shared_sint; + union hv_synic_scontrol sctrl; + + u32 irq_vector = *((u32 *)(irqarg)); + int cpu = smp_processor_id(); + + if (!hv_context.hypercall_page) + return; + + /* Check the version */ + rdmsrl(HV_X64_MSR_SVERSION, version); + + 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 cleanup; + } + + 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 cleanup; + } + + /* 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 = irq_vector; /* HV_SHARED_SINT_IDT_VECTOR + 0x20; */ + shared_sint.masked = false; + shared_sint.auto_eoi = false; + + 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; + return; + +cleanup: + 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]); + return; +} + +/* + * 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; + int cpu = smp_processor_id(); + + if (!hv_context.synic_initialized) + return; + + 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); + + free_page((unsigned long)hv_context.synic_message_page[cpu]); + free_page((unsigned long)hv_context.synic_event_page[cpu]); +} |