@@ -196,6 +196,9 @@ extern int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr,
int table_index, u64 *pte_ret_p);
extern int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
struct kvmppc_pte *gpte, bool data, bool iswrite);
+extern void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa,
+ unsigned int shift, struct kvm_memory_slot *memslot,
+ unsigned int lpid);
extern bool kvmppc_hv_handle_set_rc(struct kvm *kvm, pgd_t *pgtable,
bool writing, unsigned long gpa,
unsigned int lpid);
@@ -53,6 +53,66 @@ struct kvm_nested_guest {
struct kvm_nested_guest *next;
};
+/*
+ * We define a nested rmap entry as a single 64-bit quantity
+ * 0xFFF0000000000000 12-bit lpid field
+ * 0x000FFFFFFFFFF000 40-bit guest physical address field
+ * 0x0000000000000001 1-bit single entry flag
+ */
+#define RMAP_NESTED_LPID_MASK 0xFFF0000000000000UL
+#define RMAP_NESTED_LPID_SHIFT (52)
+#define RMAP_NESTED_GPA_MASK 0x000FFFFFFFFFF000UL
+#define RMAP_NESTED_IS_SINGLE_ENTRY 0x0000000000000001UL
+
+/* Structure for a nested guest rmap entry */
+struct rmap_nested {
+ struct llist_node list;
+ u64 rmap;
+};
+
+/*
+ * for_each_nest_rmap_safe - iterate over the list of nested rmap entries
+ * safe against removal of the list entry or NULL list
+ * @pos: a (struct rmap_nested *) to use as a loop cursor
+ * @node: pointer to the first entry
+ * NOTE: this can be NULL
+ * @rmapp: an (unsigned long *) in which to return the rmap entries on each
+ * iteration
+ * NOTE: this must point to already allocated memory
+ *
+ * The nested_rmap is a llist of (struct rmap_nested) entries pointed to by the
+ * rmap entry in the memslot. The list is always terminated by a "single entry"
+ * stored in the list element of the final entry of the llist. If there is ONLY
+ * a single entry then this is itself in the rmap entry of the memslot, not a
+ * llist head pointer.
+ *
+ * Note that the iterator below assumes that a nested rmap entry is always
+ * non-zero. This is true for our usage because the LPID field is always
+ * non-zero (zero is reserved for the host).
+ *
+ * This should be used to iterate over the list of rmap_nested entries with
+ * processing done on the u64 rmap value given by each iteration. This is safe
+ * against removal of list entries and it is always safe to call free on (pos).
+ *
+ * e.g.
+ * struct rmap_nested *cursor;
+ * struct llist_node *first;
+ * unsigned long rmap;
+ * for_each_nest_rmap_safe(cursor, first, &rmap) {
+ * do_something(rmap);
+ * free(cursor);
+ * }
+ */
+#define for_each_nest_rmap_safe(pos, node, rmapp) \
+ for ((pos) = llist_entry((node), typeof(*(pos)), list); \
+ (node) && \
+ (*(rmapp) = ((RMAP_NESTED_IS_SINGLE_ENTRY & ((u64) (node))) ? \
+ ((u64) (node)) : ((pos)->rmap))) && \
+ (((node) = ((RMAP_NESTED_IS_SINGLE_ENTRY & ((u64) (node))) ? \
+ ((struct llist_node *) ((pos) = NULL)) : \
+ (pos)->list.next)), true); \
+ (pos) = llist_entry((node), typeof(*(pos)), list))
+
struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid,
bool create);
void kvmhv_put_nested(struct kvm_nested_guest *gp);
@@ -551,7 +611,15 @@ static inline void copy_to_checkpoint(struct kvm_vcpu *vcpu)
extern int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
unsigned long gpa, unsigned int level,
- unsigned long mmu_seq, unsigned int lpid);
+ unsigned long mmu_seq, unsigned int lpid,
+ unsigned long *rmapp, struct rmap_nested **n_rmap);
+extern void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp,
+ struct rmap_nested **n_rmap);
+extern void kvmhv_remove_nest_rmap_range(struct kvm *kvm,
+ struct kvm_memory_slot *memslot,
+ unsigned long gpa, unsigned long hpa,
+ unsigned long nbytes);
+extern void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free);
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
@@ -256,27 +256,38 @@ static void kvmppc_pmd_free(pmd_t *pmdp)
kmem_cache_free(kvm_pmd_cache, pmdp);
}
-void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte,
- unsigned long gpa, unsigned int shift,
- struct kvm_memory_slot *memslot,
+/* Called with kvm->mmu_lock held */
+void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa,
+ unsigned int shift, struct kvm_memory_slot *memslot,
unsigned int lpid)
{
unsigned long old;
+ unsigned long gfn = gpa >> PAGE_SHIFT;
+ unsigned long page_size = PAGE_SIZE;
+ unsigned long hpa;
old = kvmppc_radix_update_pte(kvm, pte, ~0UL, 0, gpa, shift);
kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid);
- if ((old & _PAGE_DIRTY) && (lpid == kvm->arch.lpid)) {
- unsigned long gfn = gpa >> PAGE_SHIFT;
- unsigned long page_size = PAGE_SIZE;
- if (shift)
- page_size = 1ul << shift;
+ /* The following only applies to L1 entries */
+ if (lpid != kvm->arch.lpid)
+ return;
+
+ if (!memslot) {
+ memslot = gfn_to_memslot(kvm, gfn);
if (!memslot)
- memslot = gfn_to_memslot(kvm, gfn);
- if (memslot && memslot->dirty_bitmap)
- kvmppc_update_dirty_map(memslot, gfn, page_size);
+ return;
}
+ if (shift)
+ page_size = 1ul << shift;
+
+ gpa &= ~(page_size - 1);
+ hpa = old & PTE_RPN_MASK;
+ kvmhv_remove_nest_rmap_range(kvm, memslot, gpa, hpa, page_size);
+
+ if ((old & _PAGE_DIRTY) && memslot->dirty_bitmap)
+ kvmppc_update_dirty_map(memslot, gfn, page_size);
}
/*
@@ -432,7 +443,8 @@ static void kvmppc_unmap_free_pud_entry_table(struct kvm *kvm, pud_t *pud,
int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
unsigned long gpa, unsigned int level,
- unsigned long mmu_seq, unsigned int lpid)
+ unsigned long mmu_seq, unsigned int lpid,
+ unsigned long *rmapp, struct rmap_nested **n_rmap)
{
pgd_t *pgd;
pud_t *pud, *new_pud = NULL;
@@ -511,6 +523,8 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
kvmppc_unmap_free_pud_entry_table(kvm, pud, gpa, lpid);
}
kvmppc_radix_set_pte_at(kvm, gpa, (pte_t *)pud, pte);
+ if (rmapp && n_rmap)
+ kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap);
ret = 0;
goto out_unlock;
}
@@ -561,6 +575,8 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
kvmppc_unmap_free_pmd_entry_table(kvm, pmd, gpa, lpid);
}
kvmppc_radix_set_pte_at(kvm, gpa, pmdp_ptep(pmd), pte);
+ if (rmapp && n_rmap)
+ kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap);
ret = 0;
goto out_unlock;
}
@@ -585,6 +601,8 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
goto out_unlock;
}
kvmppc_radix_set_pte_at(kvm, gpa, ptep, pte);
+ if (rmapp && n_rmap)
+ kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap);
ret = 0;
out_unlock:
@@ -712,7 +730,7 @@ int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu,
/* Allocate space in the tree and write the PTE */
ret = kvmppc_create_pte(kvm, kvm->arch.pgtable, pte, gpa, level,
- mmu_seq, kvm->arch.lpid);
+ mmu_seq, kvm->arch.lpid, NULL, NULL);
if (inserted_pte)
*inserted_pte = pte;
if (levelp)
@@ -4292,6 +4292,7 @@ static void kvmppc_core_free_memslot_hv(struct kvm_memory_slot *free,
struct kvm_memory_slot *dont)
{
if (!dont || free->arch.rmap != dont->arch.rmap) {
+ kvmhv_free_memslot_nest_rmap(free);
vfree(free->arch.rmap);
free->arch.rmap = NULL;
}
@@ -10,6 +10,7 @@
#include <linux/kernel.h>
#include <linux/kvm_host.h>
+#include <linux/llist.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
@@ -531,6 +532,123 @@ void kvmhv_put_nested(struct kvm_nested_guest *gp)
kvmhv_release_nested(gp);
}
+static struct kvm_nested_guest *kvmhv_find_nested(struct kvm *kvm, int lpid)
+{
+ if (lpid > kvm->arch.max_nested_lpid)
+ return NULL;
+ return kvm->arch.nested_guests[lpid];
+}
+
+static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2)
+{
+ return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK |
+ RMAP_NESTED_GPA_MASK));
+}
+
+void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp,
+ struct rmap_nested **n_rmap)
+{
+ struct llist_node *entry = ((struct llist_head *) rmapp)->first;
+ struct rmap_nested *cursor;
+ u64 rmap, new_rmap = (*n_rmap)->rmap;
+
+ /* Are there any existing entries? */
+ if (!(*rmapp)) {
+ /* No -> use the rmap as a single entry */
+ *rmapp = new_rmap | RMAP_NESTED_IS_SINGLE_ENTRY;
+ return;
+ }
+
+ /* Do any entries match what we're trying to insert? */
+ for_each_nest_rmap_safe(cursor, entry, &rmap) {
+ if (kvmhv_n_rmap_is_equal(rmap, new_rmap))
+ return;
+ }
+
+ /* Do we need to create a list or just add the new entry? */
+ rmap = *rmapp;
+ if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
+ *rmapp = 0UL;
+ llist_add(&((*n_rmap)->list), (struct llist_head *) rmapp);
+ if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
+ (*n_rmap)->list.next = (struct llist_node *) rmap;
+
+ /* Set NULL so not freed by caller */
+ *n_rmap = NULL;
+}
+
+static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap,
+ unsigned long hpa, unsigned long mask)
+{
+ struct kvm_nested_guest *gp;
+ unsigned long gpa;
+ unsigned int shift, lpid;
+ pte_t *ptep;
+
+ gpa = n_rmap & RMAP_NESTED_GPA_MASK;
+ lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
+ gp = kvmhv_find_nested(kvm, lpid);
+ if (!gp)
+ return;
+
+ /* Find and invalidate the pte */
+ ptep = __find_linux_pte(gp->shadow_pgtable, gpa, NULL, &shift);
+ /* Don't spuriously invalidate ptes if the pfn has changed */
+ if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa))
+ kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
+}
+
+static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp,
+ unsigned long hpa, unsigned long mask)
+{
+ struct llist_node *entry = llist_del_all((struct llist_head *) rmapp);
+ struct rmap_nested *cursor;
+ unsigned long rmap;
+
+ for_each_nest_rmap_safe(cursor, entry, &rmap) {
+ kvmhv_remove_nest_rmap(kvm, rmap, hpa, mask);
+ kfree(cursor);
+ }
+}
+
+/* called with kvm->mmu_lock held */
+void kvmhv_remove_nest_rmap_range(struct kvm *kvm,
+ struct kvm_memory_slot *memslot,
+ unsigned long gpa, unsigned long hpa,
+ unsigned long nbytes)
+{
+ unsigned long gfn, end_gfn;
+ unsigned long addr_mask;
+
+ if (!memslot)
+ return;
+ gfn = (gpa >> PAGE_SHIFT) - memslot->base_gfn;
+ end_gfn = gfn + (nbytes >> PAGE_SHIFT);
+
+ addr_mask = PTE_RPN_MASK & ~(nbytes - 1);
+ hpa &= addr_mask;
+
+ for (; gfn < end_gfn; gfn++) {
+ unsigned long *rmap = &memslot->arch.rmap[gfn];
+ kvmhv_remove_nest_rmap_list(kvm, rmap, hpa, addr_mask);
+ }
+}
+
+void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free)
+{
+ unsigned long page;
+
+ for (page = 0; page < free->npages; page++) {
+ unsigned long rmap, *rmapp = &free->arch.rmap[page];
+ struct rmap_nested *cursor;
+ struct llist_node *entry;
+
+ entry = llist_del_all((struct llist_head *) rmapp);
+ for_each_nest_rmap_safe(cursor, entry, &rmap)
+ kfree(cursor);
+ }
+}
+
static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu,
struct kvm_nested_guest *gp,
long gpa, int *shift_ret)
@@ -736,11 +854,13 @@ static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
{
struct kvm *kvm = vcpu->kvm;
struct kvm_memory_slot *memslot;
+ struct rmap_nested *n_rmap;
struct kvmppc_pte gpte;
pte_t pte, *pte_p;
unsigned long mmu_seq;
unsigned long dsisr = vcpu->arch.fault_dsisr;
unsigned long ea = vcpu->arch.fault_dar;
+ unsigned long *rmapp;
unsigned long n_gpa, gpa, gfn, perm = 0UL;
unsigned int shift, l1_shift, level;
bool writing = !!(dsisr & DSISR_ISSTORE);
@@ -874,8 +994,16 @@ static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
/* 4. Insert the pte into our shadow_pgtable */
+ n_rmap = kzalloc(sizeof(*n_rmap), GFP_KERNEL);
+ if (!n_rmap)
+ return RESUME_GUEST; /* Let the guest try again */
+ n_rmap->rmap = (n_gpa & RMAP_NESTED_GPA_MASK) |
+ (((unsigned long) gp->l1_lpid) << RMAP_NESTED_LPID_SHIFT);
+ rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level,
- mmu_seq, gp->shadow_lpid);
+ mmu_seq, gp->shadow_lpid, rmapp, &n_rmap);
+ if (n_rmap)
+ kfree(n_rmap);
if (ret == -EAGAIN)
ret = RESUME_GUEST; /* Let the guest try again */