2023-12-28 10:53:04

by Yi-De Wu

[permalink] [raw]
Subject: [PATCH v8 17/20] virt: geniezone: Add memory relinquish support

From: "Jerry Wang" <[email protected]>

Unpin the pages when VM relinquish the pages or is destroyed.

Signed-off-by: Jerry Wang <[email protected]>
Signed-off-by: Yingshiuan Pan <[email protected]>
Signed-off-by: Liju-Clr Chen <[email protected]>
Signed-off-by: Yi-De Wu <[email protected]>
---
drivers/virt/geniezone/gzvm_exception.c | 23 +++++++++++++++
drivers/virt/geniezone/gzvm_mmu.c | 39 +++++++++++++++++++++++++
drivers/virt/geniezone/gzvm_vcpu.c | 6 ++--
include/linux/gzvm_drv.h | 2 ++
include/uapi/linux/gzvm.h | 5 ++++
5 files changed, 73 insertions(+), 2 deletions(-)

diff --git a/drivers/virt/geniezone/gzvm_exception.c b/drivers/virt/geniezone/gzvm_exception.c
index 31fdb4ae8db4..af26d1c82791 100644
--- a/drivers/virt/geniezone/gzvm_exception.c
+++ b/drivers/virt/geniezone/gzvm_exception.c
@@ -37,3 +37,26 @@ bool gzvm_handle_guest_exception(struct gzvm_vcpu *vcpu)
else
return false;
}
+
+/**
+ * gzvm_handle_guest_hvc() - Handle guest hvc
+ * @vcpu: Pointer to struct gzvm_vcpu struct
+ * Return:
+ * * true - This hvc has been processed, no need to back to VMM.
+ * * false - This hvc has not been processed, require userspace.
+ */
+bool gzvm_handle_guest_hvc(struct gzvm_vcpu *vcpu)
+{
+ unsigned long ipa;
+ int ret;
+
+ switch (vcpu->run->hypercall.args[0]) {
+ case GZVM_HVC_MEM_RELINQUISH:
+ ipa = vcpu->run->hypercall.args[1];
+ ret = gzvm_handle_relinquish(vcpu, ipa);
+ return (ret == 0) ? true : false;
+ default:
+ break;
+ }
+ return false;
+}
diff --git a/drivers/virt/geniezone/gzvm_mmu.c b/drivers/virt/geniezone/gzvm_mmu.c
index 857cc68f76dc..ab0afec48381 100644
--- a/drivers/virt/geniezone/gzvm_mmu.c
+++ b/drivers/virt/geniezone/gzvm_mmu.c
@@ -141,6 +141,26 @@ static int gzvm_insert_ppage(struct gzvm *vm, struct gzvm_pinned_page *ppage)
return 0;
}

+/* Invoker of this function is responsible for locking */
+static int gzvm_remove_ppage(struct gzvm *vm, phys_addr_t ipa)
+{
+ struct gzvm_pinned_page *ppage;
+ struct rb_node *node;
+
+ node = rb_find((void *)ipa, &vm->pinned_pages, rb_ppage_cmp);
+
+ if (node)
+ rb_erase(node, &vm->pinned_pages);
+ else
+ return 0;
+
+ ppage = container_of(node, struct gzvm_pinned_page, node);
+ unpin_user_pages_dirty_lock(&ppage->page, 1, true);
+ kfree(ppage);
+
+ return 0;
+}
+
static int pin_one_page(struct gzvm *vm, unsigned long hva, u64 gpa)
{
unsigned int flags = FOLL_HWPOISON | FOLL_LONGTERM | FOLL_WRITE;
@@ -171,6 +191,25 @@ static int pin_one_page(struct gzvm *vm, unsigned long hva, u64 gpa)
return 0;
}

+/**
+ * gzvm_handle_relinquish() - Handle memory relinquish request from hypervisor
+ *
+ * @vcpu: Pointer to struct gzvm_vcpu_run in userspace
+ * @ipa: Start address(gpa) of a reclaimed page
+ *
+ * Return: Always return 0 because there are no cases of failure
+ */
+int gzvm_handle_relinquish(struct gzvm_vcpu *vcpu, phys_addr_t ipa)
+{
+ struct gzvm *vm = vcpu->gzvm;
+
+ mutex_lock(&vm->mem_lock);
+ gzvm_remove_ppage(vm, ipa);
+ mutex_unlock(&vm->mem_lock);
+
+ return 0;
+}
+
static int handle_block_demand_page(struct gzvm *vm, int memslot_id, u64 gfn)
{
unsigned long hva;
diff --git a/drivers/virt/geniezone/gzvm_vcpu.c b/drivers/virt/geniezone/gzvm_vcpu.c
index 455ae2e4285c..86c690749277 100644
--- a/drivers/virt/geniezone/gzvm_vcpu.c
+++ b/drivers/virt/geniezone/gzvm_vcpu.c
@@ -113,12 +113,14 @@ static long gzvm_vcpu_run(struct gzvm_vcpu *vcpu, void __user *argp)
* it's geniezone's responsibility to fill corresponding data
* structure
*/
+ case GZVM_EXIT_HYPERCALL:
+ if (!gzvm_handle_guest_hvc(vcpu))
+ need_userspace = true;
+ break;
case GZVM_EXIT_EXCEPTION:
if (!gzvm_handle_guest_exception(vcpu))
need_userspace = true;
break;
- case GZVM_EXIT_HYPERCALL:
- fallthrough;
case GZVM_EXIT_DEBUG:
fallthrough;
case GZVM_EXIT_FAIL_ENTRY:
diff --git a/include/linux/gzvm_drv.h b/include/linux/gzvm_drv.h
index 116d1d7c1562..17f5fb9d843d 100644
--- a/include/linux/gzvm_drv.h
+++ b/include/linux/gzvm_drv.h
@@ -175,6 +175,8 @@ int gzvm_arch_inform_exit(u16 vm_id);
int gzvm_find_memslot(struct gzvm *vm, u64 gpa);
int gzvm_handle_page_fault(struct gzvm_vcpu *vcpu);
bool gzvm_handle_guest_exception(struct gzvm_vcpu *vcpu);
+int gzvm_handle_relinquish(struct gzvm_vcpu *vcpu, phys_addr_t ipa);
+bool gzvm_handle_guest_hvc(struct gzvm_vcpu *vcpu);

int gzvm_arch_create_device(u16 vm_id, struct gzvm_create_device *gzvm_dev);
int gzvm_arch_inject_irq(struct gzvm *gzvm, unsigned int vcpu_idx,
diff --git a/include/uapi/linux/gzvm.h b/include/uapi/linux/gzvm.h
index f858b04bf7b9..a98787a18c36 100644
--- a/include/uapi/linux/gzvm.h
+++ b/include/uapi/linux/gzvm.h
@@ -193,6 +193,11 @@ enum {
GZVM_EXCEPTION_PAGE_FAULT = 0x1,
};

+/* hypercall definitions of GZVM_EXIT_HYPERCALL */
+enum {
+ GZVM_HVC_MEM_RELINQUISH = 0xc6000009,
+};
+
/**
* struct gzvm_vcpu_run: Same purpose as kvm_run, this struct is
* shared between userspace, kernel and
--
2.18.0