diff options
Diffstat (limited to 'drivers/hv/hv.c')
| -rw-r--r-- | drivers/hv/hv.c | 152 |
1 files changed, 129 insertions, 23 deletions
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index f202ac7f4b3d..e83507f49676 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -13,9 +13,10 @@ #include <linux/slab.h> #include <linux/vmalloc.h> #include <linux/hyperv.h> -#include <linux/version.h> #include <linux/random.h> #include <linux/clockchips.h> +#include <linux/delay.h> +#include <linux/interrupt.h> #include <clocksource/hyperv_timer.h> #include <asm/mshyperv.h> #include "hyperv_vmbus.h" @@ -37,6 +38,42 @@ int hv_init(void) } /* + * Functions for allocating and freeing memory with size and + * alignment HV_HYP_PAGE_SIZE. These functions are needed because + * the guest page size may not be the same as the Hyper-V page + * size. We depend upon kmalloc() aligning power-of-two size + * allocations to the allocation size boundary, so that the + * allocated memory appears to Hyper-V as a page of the size + * it expects. + */ + +void *hv_alloc_hyperv_page(void) +{ + BUILD_BUG_ON(PAGE_SIZE < HV_HYP_PAGE_SIZE); + + if (PAGE_SIZE == HV_HYP_PAGE_SIZE) + return (void *)__get_free_page(GFP_KERNEL); + else + return kmalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL); +} + +void *hv_alloc_hyperv_zeroed_page(void) +{ + if (PAGE_SIZE == HV_HYP_PAGE_SIZE) + return (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + else + return kzalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL); +} + +void hv_free_hyperv_page(unsigned long addr) +{ + if (PAGE_SIZE == HV_HYP_PAGE_SIZE) + free_page(addr); + else + kfree((void *)addr); +} + +/* * hv_post_message - Post a message using the hypervisor message IPC. * * This involves a hypercall. @@ -68,7 +105,7 @@ int hv_post_message(union hv_connection_id connection_id, */ put_cpu_ptr(hv_cpu); - return status & 0xFFFF; + return hv_result(status); } int hv_synic_alloc(void) @@ -162,34 +199,48 @@ void hv_synic_enable_regs(unsigned int cpu) union hv_synic_scontrol sctrl; /* Setup the Synic's message page */ - hv_get_simp(simp.as_uint64); + simp.as_uint64 = hv_get_register(HV_REGISTER_SIMP); simp.simp_enabled = 1; simp.base_simp_gpa = virt_to_phys(hv_cpu->synic_message_page) >> HV_HYP_PAGE_SHIFT; - hv_set_simp(simp.as_uint64); + hv_set_register(HV_REGISTER_SIMP, simp.as_uint64); /* Setup the Synic's event page */ - hv_get_siefp(siefp.as_uint64); + siefp.as_uint64 = hv_get_register(HV_REGISTER_SIEFP); siefp.siefp_enabled = 1; siefp.base_siefp_gpa = virt_to_phys(hv_cpu->synic_event_page) >> HV_HYP_PAGE_SHIFT; - hv_set_siefp(siefp.as_uint64); + hv_set_register(HV_REGISTER_SIEFP, siefp.as_uint64); /* Setup the shared SINT. */ - hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); + if (vmbus_irq != -1) + enable_percpu_irq(vmbus_irq, 0); + shared_sint.as_uint64 = hv_get_register(HV_REGISTER_SINT0 + + VMBUS_MESSAGE_SINT); - shared_sint.vector = hv_get_vector(); + shared_sint.vector = vmbus_interrupt; shared_sint.masked = false; - shared_sint.auto_eoi = hv_recommend_using_aeoi(); - hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); + + /* + * On architectures where Hyper-V doesn't support AEOI (e.g., ARM64), + * it doesn't provide a recommendation flag and AEOI must be disabled. + */ +#ifdef HV_DEPRECATING_AEOI_RECOMMENDED + shared_sint.auto_eoi = + !(ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED); +#else + shared_sint.auto_eoi = 0; +#endif + hv_set_register(HV_REGISTER_SINT0 + VMBUS_MESSAGE_SINT, + shared_sint.as_uint64); /* Enable the global synic bit */ - hv_get_synic_state(sctrl.as_uint64); + sctrl.as_uint64 = hv_get_register(HV_REGISTER_SCONTROL); sctrl.enable = 1; - hv_set_synic_state(sctrl.as_uint64); + hv_set_register(HV_REGISTER_SCONTROL, sctrl.as_uint64); } int hv_synic_init(unsigned int cpu) @@ -211,30 +262,71 @@ void hv_synic_disable_regs(unsigned int cpu) union hv_synic_siefp siefp; union hv_synic_scontrol sctrl; - hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); + shared_sint.as_uint64 = hv_get_register(HV_REGISTER_SINT0 + + VMBUS_MESSAGE_SINT); shared_sint.masked = 1; /* Need to correctly cleanup in the case of SMP!!! */ /* Disable the interrupt */ - hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); + hv_set_register(HV_REGISTER_SINT0 + VMBUS_MESSAGE_SINT, + shared_sint.as_uint64); - hv_get_simp(simp.as_uint64); + simp.as_uint64 = hv_get_register(HV_REGISTER_SIMP); simp.simp_enabled = 0; simp.base_simp_gpa = 0; - hv_set_simp(simp.as_uint64); + hv_set_register(HV_REGISTER_SIMP, simp.as_uint64); - hv_get_siefp(siefp.as_uint64); + siefp.as_uint64 = hv_get_register(HV_REGISTER_SIEFP); siefp.siefp_enabled = 0; siefp.base_siefp_gpa = 0; - hv_set_siefp(siefp.as_uint64); + hv_set_register(HV_REGISTER_SIEFP, siefp.as_uint64); /* Disable the global synic bit */ - hv_get_synic_state(sctrl.as_uint64); + sctrl.as_uint64 = hv_get_register(HV_REGISTER_SCONTROL); sctrl.enable = 0; - hv_set_synic_state(sctrl.as_uint64); + hv_set_register(HV_REGISTER_SCONTROL, sctrl.as_uint64); + + if (vmbus_irq != -1) + disable_percpu_irq(vmbus_irq); +} + +#define HV_MAX_TRIES 3 +/* + * Scan the event flags page of 'this' CPU looking for any bit that is set. If we find one + * bit set, then wait for a few milliseconds. Repeat these steps for a maximum of 3 times. + * Return 'true', if there is still any set bit after this operation; 'false', otherwise. + * + * If a bit is set, that means there is a pending channel interrupt. The expectation is + * that the normal interrupt handling mechanism will find and process the channel interrupt + * "very soon", and in the process clear the bit. + */ +static bool hv_synic_event_pending(void) +{ + struct hv_per_cpu_context *hv_cpu = this_cpu_ptr(hv_context.cpu_context); + union hv_synic_event_flags *event = + (union hv_synic_event_flags *)hv_cpu->synic_event_page + VMBUS_MESSAGE_SINT; + unsigned long *recv_int_page = event->flags; /* assumes VMBus version >= VERSION_WIN8 */ + bool pending; + u32 relid; + int tries = 0; + +retry: + pending = false; + for_each_set_bit(relid, recv_int_page, HV_EVENT_FLAGS_COUNT) { + /* Special case - VMBus channel protocol messages */ + if (relid == 0) + continue; + pending = true; + break; + } + if (pending && tries++ < HV_MAX_TRIES) { + usleep_range(10000, 20000); + goto retry; + } + return pending; } int hv_synic_cleanup(unsigned int cpu) @@ -242,6 +334,9 @@ int hv_synic_cleanup(unsigned int cpu) struct vmbus_channel *channel, *sc; bool channel_found = false; + if (vmbus_connection.conn_state != CONNECTED) + goto always_cleanup; + /* * Hyper-V does not provide a way to change the connect CPU once * it is set; we must prevent the connect CPU from going offline @@ -249,8 +344,7 @@ int hv_synic_cleanup(unsigned int cpu) * path where the vmbus is already disconnected, the CPU must be * allowed to shut down. */ - if (cpu == VMBUS_CONNECT_CPU && - vmbus_connection.conn_state == CONNECTED) + if (cpu == VMBUS_CONNECT_CPU) return -EBUSY; /* @@ -277,9 +371,21 @@ int hv_synic_cleanup(unsigned int cpu) } mutex_unlock(&vmbus_connection.channel_mutex); - if (channel_found && vmbus_connection.conn_state == CONNECTED) + if (channel_found) + return -EBUSY; + + /* + * channel_found == false means that any channels that were previously + * assigned to the CPU have been reassigned elsewhere with a call of + * vmbus_send_modifychannel(). Scan the event flags page looking for + * bits that are set and waiting with a timeout for vmbus_chan_sched() + * to process such bits. If bits are still set after this operation + * and VMBus is connected, fail the CPU offlining operation. + */ + if (vmbus_proto_version >= VERSION_WIN10_V4_1 && hv_synic_event_pending()) return -EBUSY; +always_cleanup: hv_stimer_legacy_cleanup(cpu); hv_synic_disable_regs(cpu); |