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authorMaxime Ripard <maxime@cerno.tech>2021-05-11 13:35:52 +0200
committerMaxime Ripard <maxime@cerno.tech>2021-05-11 13:35:52 +0200
commitc55b44c9386f3ee1b08752638559f19deaf6040d (patch)
treec843a21f45180387fcd9eb2625cc9d1f166a3156 /drivers/hv/hv.c
parentMAINTAINERS: Update my e-mail (diff)
parentLinux 5.13-rc1 (diff)
downloadlinux-c55b44c9386f3ee1b08752638559f19deaf6040d.tar.xz
linux-c55b44c9386f3ee1b08752638559f19deaf6040d.zip
Merge drm/drm-fixes into drm-misc-fixes
Start this new release drm-misc-fixes branch Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Diffstat (limited to 'drivers/hv/hv.c')
-rw-r--r--drivers/hv/hv.c152
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);