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-rw-r--r--arch/s390/include/asm/gmap.h52
-rw-r--r--arch/s390/include/asm/pgalloc.h2
-rw-r--r--arch/s390/include/asm/pgtable.h10
-rw-r--r--arch/s390/include/asm/processor.h1
-rw-r--r--arch/s390/mm/fault.c1
-rw-r--r--arch/s390/mm/gmap.c1150
-rw-r--r--arch/s390/mm/pgalloc.c23
-rw-r--r--arch/s390/mm/pgtable.c57
8 files changed, 1262 insertions, 34 deletions
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index e69853ce55da..58e65ee5b2d2 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -10,6 +10,7 @@
/**
* struct gmap_struct - guest address space
+ * @list: list head for the mm->context gmap list
* @crst_list: list of all crst tables used in the guest address space
* @mm: pointer to the parent mm_struct
* @guest_to_host: radix tree with guest to host address translation
@@ -19,6 +20,13 @@
* @table: pointer to the page directory
* @asce: address space control element for gmap page table
* @pfault_enabled: defines if pfaults are applicable for the guest
+ * @host_to_rmap: radix tree with gmap_rmap lists
+ * @children: list of shadow gmap structures
+ * @pt_list: list of all page tables used in the shadow guest address space
+ * @shadow_lock: spinlock to protect the shadow gmap list
+ * @parent: pointer to the parent gmap for shadow guest address spaces
+ * @orig_asce: ASCE for which the shadow page table has been created
+ * @removed: flag to indicate if a shadow guest address space has been removed
*/
struct gmap {
struct list_head list;
@@ -33,9 +41,33 @@ struct gmap {
unsigned long asce_end;
void *private;
bool pfault_enabled;
+ /* Additional data for shadow guest address spaces */
+ struct radix_tree_root host_to_rmap;
+ struct list_head children;
+ struct list_head pt_list;
+ spinlock_t shadow_lock;
+ struct gmap *parent;
+ unsigned long orig_asce;
+ bool removed;
};
/**
+ * struct gmap_rmap - reverse mapping for shadow page table entries
+ * @next: pointer to next rmap in the list
+ * @raddr: virtual rmap address in the shadow guest address space
+ */
+struct gmap_rmap {
+ struct gmap_rmap *next;
+ unsigned long raddr;
+};
+
+#define gmap_for_each_rmap(pos, head) \
+ for (pos = (head); pos; pos = pos->next)
+
+#define gmap_for_each_rmap_safe(pos, n, head) \
+ for (pos = (head); n = pos ? pos->next : NULL, pos; pos = n)
+
+/**
* struct gmap_notifier - notify function block for page invalidation
* @notifier_call: address of callback function
*/
@@ -46,6 +78,11 @@ struct gmap_notifier {
unsigned long end);
};
+static inline int gmap_is_shadow(struct gmap *gmap)
+{
+ return !!gmap->parent;
+}
+
struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit);
void gmap_remove(struct gmap *gmap);
struct gmap *gmap_get(struct gmap *gmap);
@@ -64,9 +101,22 @@ void gmap_discard(struct gmap *, unsigned long from, unsigned long to);
void __gmap_zap(struct gmap *, unsigned long gaddr);
void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr);
+int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
+
+struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce);
+int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t);
+int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t);
+int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt);
+int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt);
+int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
+ unsigned long *pgt, int *dat_protection);
+int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
+ unsigned long paddr, int write);
+
void gmap_register_pte_notifier(struct gmap_notifier *);
void gmap_unregister_pte_notifier(struct gmap_notifier *);
-void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *);
+void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *,
+ unsigned long bits);
int gmap_mprotect_notify(struct gmap *, unsigned long start,
unsigned long len, int prot);
diff --git a/arch/s390/include/asm/pgalloc.h b/arch/s390/include/asm/pgalloc.h
index da34cb6b1f3b..f4eb9843eed4 100644
--- a/arch/s390/include/asm/pgalloc.h
+++ b/arch/s390/include/asm/pgalloc.h
@@ -19,8 +19,10 @@ unsigned long *crst_table_alloc(struct mm_struct *);
void crst_table_free(struct mm_struct *, unsigned long *);
unsigned long *page_table_alloc(struct mm_struct *);
+struct page *page_table_alloc_pgste(struct mm_struct *mm);
void page_table_free(struct mm_struct *, unsigned long *);
void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
+void page_table_free_pgste(struct page *page);
extern int page_table_allocate_pgste;
static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 35dde6afffcf..a6e7fc8f5b49 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -256,6 +256,7 @@ static inline int is_module_addr(void *addr)
/* Bits in the region table entry */
#define _REGION_ENTRY_ORIGIN ~0xfffUL/* region/segment table origin */
#define _REGION_ENTRY_PROTECT 0x200 /* region protection bit */
+#define _REGION_ENTRY_OFFSET 0xc0 /* region table offset */
#define _REGION_ENTRY_INVALID 0x20 /* invalid region table entry */
#define _REGION_ENTRY_TYPE_MASK 0x0c /* region/segment table type mask */
#define _REGION_ENTRY_TYPE_R1 0x0c /* region first table type */
@@ -327,6 +328,7 @@ static inline int is_module_addr(void *addr)
#define PGSTE_GC_BIT 0x0002000000000000UL
#define PGSTE_UC_BIT 0x0000800000000000UL /* user dirty (migration) */
#define PGSTE_IN_BIT 0x0000400000000000UL /* IPTE notify bit */
+#define PGSTE_VSIE_BIT 0x0000200000000000UL /* ref'd in a shadow table */
/* Guest Page State used for virtualization */
#define _PGSTE_GPS_ZERO 0x0000000080000000UL
@@ -885,12 +887,16 @@ static inline int ptep_set_access_flags(struct vm_area_struct *vma,
void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t entry);
void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
-void ptep_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
+void ptep_notify(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, unsigned long bits);
int ptep_force_prot(struct mm_struct *mm, unsigned long gaddr,
- pte_t *ptep, int prot);
+ pte_t *ptep, int prot, unsigned long bit);
void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
pte_t *ptep , int reset);
void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
+int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
+ pte_t *sptep, pte_t *tptep, int write);
+void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep);
bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long address);
int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index 9d4d311d7e52..94c80b6d031d 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -109,6 +109,7 @@ struct thread_struct {
unsigned long ksp; /* kernel stack pointer */
mm_segment_t mm_segment;
unsigned long gmap_addr; /* address of last gmap fault. */
+ unsigned int gmap_write_flag; /* gmap fault write indication */
unsigned int gmap_pfault; /* signal of a pending guest pfault */
struct per_regs per_user; /* User specified PER registers */
struct per_event per_event; /* Cause of the last PER trap */
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 19288c1b36d3..b84416c11c43 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -418,6 +418,7 @@ static inline int do_exception(struct pt_regs *regs, int access)
(struct gmap *) S390_lowcore.gmap : NULL;
if (gmap) {
current->thread.gmap_addr = address;
+ current->thread.gmap_write_flag = !!(flags & FAULT_FLAG_WRITE);
address = __gmap_translate(gmap, address);
if (address == -EFAULT) {
fault = VM_FAULT_BADMAP;
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index fe25f1915800..6695a09a3885 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -55,9 +55,13 @@ static struct gmap *gmap_alloc(unsigned long limit)
if (!gmap)
goto out;
INIT_LIST_HEAD(&gmap->crst_list);
+ INIT_LIST_HEAD(&gmap->children);
+ INIT_LIST_HEAD(&gmap->pt_list);
INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL);
INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC);
+ INIT_RADIX_TREE(&gmap->host_to_rmap, GFP_ATOMIC);
spin_lock_init(&gmap->guest_table_lock);
+ spin_lock_init(&gmap->shadow_lock);
atomic_set(&gmap->ref_count, 1);
page = alloc_pages(GFP_KERNEL, 2);
if (!page)
@@ -132,9 +136,38 @@ static void gmap_radix_tree_free(struct radix_tree_root *root)
} while (nr > 0);
}
+static void gmap_rmap_radix_tree_free(struct radix_tree_root *root)
+{
+ struct gmap_rmap *rmap, *rnext, *head;
+ struct radix_tree_iter iter;
+ unsigned long indices[16];
+ unsigned long index;
+ void **slot;
+ int i, nr;
+
+ /* A radix tree is freed by deleting all of its entries */
+ index = 0;
+ do {
+ nr = 0;
+ radix_tree_for_each_slot(slot, root, &iter, index) {
+ indices[nr] = iter.index;
+ if (++nr == 16)
+ break;
+ }
+ for (i = 0; i < nr; i++) {
+ index = indices[i];
+ head = radix_tree_delete(root, index);
+ gmap_for_each_rmap_safe(rmap, rnext, head)
+ kfree(rmap);
+ }
+ } while (nr > 0);
+}
+
/**
* gmap_free - free a guest address space
* @gmap: pointer to the guest address space structure
+ *
+ * No locks required. There are no references to this gmap anymore.
*/
static void gmap_free(struct gmap *gmap)
{
@@ -145,6 +178,17 @@ static void gmap_free(struct gmap *gmap)
__free_pages(page, 2);
gmap_radix_tree_free(&gmap->guest_to_host);
gmap_radix_tree_free(&gmap->host_to_guest);
+
+ /* Free additional data for a shadow gmap */
+ if (gmap_is_shadow(gmap)) {
+ /* Free all page tables. */
+ list_for_each_entry_safe(page, next, &gmap->pt_list, lru)
+ page_table_free_pgste(page);
+ gmap_rmap_radix_tree_free(&gmap->host_to_rmap);
+ /* Release reference to the parent */
+ gmap_put(gmap->parent);
+ }
+
kfree(gmap);
}
@@ -180,8 +224,20 @@ EXPORT_SYMBOL_GPL(gmap_put);
*/
void gmap_remove(struct gmap *gmap)
{
+ struct gmap *sg, *next;
+
/* Flush tlb. */
gmap_flush_tlb(gmap);
+ /* Remove all shadow gmaps linked to this gmap */
+ if (!list_empty(&gmap->children)) {
+ spin_lock(&gmap->shadow_lock);
+ list_for_each_entry_safe(sg, next, &gmap->children, list) {
+ gmap_flush_tlb(sg);
+ list_del(&sg->list);
+ gmap_put(sg);
+ }
+ spin_unlock(&gmap->shadow_lock);
+ }
/* Remove gmap from the pre-mm list */
spin_lock(&gmap->mm->context.gmap_lock);
list_del_rcu(&gmap->list);
@@ -227,7 +283,7 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table,
return -ENOMEM;
new = (unsigned long *) page_to_phys(page);
crst_table_init(new, init);
- spin_lock(&gmap->mm->page_table_lock);
+ spin_lock(&gmap->guest_table_lock);
if (*table & _REGION_ENTRY_INVALID) {
list_add(&page->lru, &gmap->crst_list);
*table = (unsigned long) new | _REGION_ENTRY_LENGTH |
@@ -235,7 +291,7 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table,
page->index = gaddr;
page = NULL;
}
- spin_unlock(&gmap->mm->page_table_lock);
+ spin_unlock(&gmap->guest_table_lock);
if (page)
__free_pages(page, 2);
return 0;
@@ -271,6 +327,7 @@ static int __gmap_unlink_by_vmaddr(struct gmap *gmap, unsigned long vmaddr)
unsigned long *entry;
int flush = 0;
+ BUG_ON(gmap_is_shadow(gmap));
spin_lock(&gmap->guest_table_lock);
entry = radix_tree_delete(&gmap->host_to_guest, vmaddr >> PMD_SHIFT);
if (entry) {
@@ -310,6 +367,7 @@ int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len)
unsigned long off;
int flush;
+ BUG_ON(gmap_is_shadow(gmap));
if ((to | len) & (PMD_SIZE - 1))
return -EINVAL;
if (len == 0 || to + len < to)
@@ -341,6 +399,7 @@ int gmap_map_segment(struct gmap *gmap, unsigned long from,
unsigned long off;
int flush;
+ BUG_ON(gmap_is_shadow(gmap));
if ((from | to | len) & (PMD_SIZE - 1))
return -EINVAL;
if (len == 0 || from + len < from || to + len < to ||
@@ -378,6 +437,8 @@ EXPORT_SYMBOL_GPL(gmap_map_segment);
* This function does not establish potentially missing page table entries.
* The mmap_sem of the mm that belongs to the address space must be held
* when this function gets called.
+ *
+ * Note: Can also be called for shadow gmaps.
*/
unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr)
{
@@ -385,6 +446,7 @@ unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr)
vmaddr = (unsigned long)
radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT);
+ /* Note: guest_to_host is empty for a shadow gmap */
return vmaddr ? (vmaddr | (gaddr & ~PMD_MASK)) : -EFAULT;
}
EXPORT_SYMBOL_GPL(__gmap_translate);
@@ -451,6 +513,7 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr)
pmd_t *pmd;
int rc;
+ BUG_ON(gmap_is_shadow(gmap));
/* Create higher level tables in the gmap page table */
table = gmap->table;
if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION1) {
@@ -646,36 +709,65 @@ static void gmap_call_notifier(struct gmap *gmap, unsigned long start,
* gmap_table_walk - walk the gmap page tables
* @gmap: pointer to guest mapping meta data structure
* @gaddr: virtual address in the guest address space
+ * @level: page table level to stop at
+ *
+ * Returns a table entry pointer for the given guest address and @level
+ * @level=0 : returns a pointer to a page table table entry (or NULL)
+ * @level=1 : returns a pointer to a segment table entry (or NULL)
+ * @level=2 : returns a pointer to a region-3 table entry (or NULL)
+ * @level=3 : returns a pointer to a region-2 table entry (or NULL)
+ * @level=4 : returns a pointer to a region-1 table entry (or NULL)
+ *
+ * Returns NULL if the gmap page tables could not be walked to the
+ * requested level.
*
- * Returns a table pointer for the given guest address.
+ * Note: Can also be called for shadow gmaps.
*/
static inline unsigned long *gmap_table_walk(struct gmap *gmap,
- unsigned long gaddr)
+ unsigned long gaddr, int level)
{
unsigned long *table;
+ if ((gmap->asce & _ASCE_TYPE_MASK) + 4 < (level * 4))
+ return NULL;
+ if (gmap_is_shadow(gmap) && gmap->removed)
+ return NULL;
+ if (gaddr & (-1UL << (31 + ((gmap->asce & _ASCE_TYPE_MASK) >> 2)*11)))
+ return NULL;
table = gmap->table;
switch (gmap->asce & _ASCE_TYPE_MASK) {
case _ASCE_TYPE_REGION1:
table += (gaddr >> 53) & 0x7ff;
+ if (level == 4)
+ break;
if (*table & _REGION_ENTRY_INVALID)
return NULL;
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
/* Fallthrough */
case _ASCE_TYPE_REGION2:
table += (gaddr >> 42) & 0x7ff;
+ if (level == 3)
+ break;
if (*table & _REGION_ENTRY_INVALID)
return NULL;
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
/* Fallthrough */
case _ASCE_TYPE_REGION3:
table += (gaddr >> 31) & 0x7ff;
+ if (level == 2)
+ break;
if (*table & _REGION_ENTRY_INVALID)
return NULL;
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
/* Fallthrough */
case _ASCE_TYPE_SEGMENT:
table += (gaddr >> 20) & 0x7ff;
+ if (level == 1)
+ break;
+ if (*table & _REGION_ENTRY_INVALID)
+ return NULL;
+ table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN);
+ table += (gaddr >> 12) & 0xff;
}
return table;
}
@@ -688,16 +780,27 @@ static inline unsigned long *gmap_table_walk(struct gmap *gmap,
* @ptl: pointer to the spinlock pointer
*
* Returns a pointer to the locked pte for a guest address, or NULL
+ *
+ * Note: Can also be called for shadow gmaps.
*/
static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
spinlock_t **ptl)
{
unsigned long *table;
+ if (gmap_is_shadow(gmap))
+ spin_lock(&gmap->guest_table_lock);
/* Walk the gmap page table, lock and get pte pointer */
- table = gmap_table_walk(gmap, gaddr);
- if (!table || *table & _SEGMENT_ENTRY_INVALID)
+ table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */
+ if (!table || *table & _SEGMENT_ENTRY_INVALID) {
+ if (gmap_is_shadow(gmap))
+ spin_unlock(&gmap->guest_table_lock);
return NULL;
+ }
+ if (gmap_is_shadow(gmap)) {
+ *ptl = &gmap->guest_table_lock;
+ return pte_offset_map((pmd_t *) table, gaddr);
+ }
return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl);
}
@@ -717,6 +820,7 @@ static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr,
struct mm_struct *mm = gmap->mm;
bool unlocked = false;
+ BUG_ON(gmap_is_shadow(gmap));
if (fixup_user_fault(current, mm, vmaddr, FAULT_FLAG_WRITE, &unlocked))
return -EFAULT;
if (unlocked)
@@ -735,6 +839,51 @@ static void gmap_pte_op_end(spinlock_t *ptl)
spin_unlock(ptl);
}
+/*
+ * gmap_protect_range - remove access rights to memory and set pgste bits
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @len: size of area
+ * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ * @bits: pgste notification bits to set
+ *
+ * Returns 0 if successfully protected, -ENOMEM if out of memory and
+ * -EFAULT if gaddr is invalid (or mapping for shadows is missing).
+ *
+ * Called with sg->mm->mmap_sem in read.
+ *
+ * Note: Can also be called for shadow gmaps.
+ */
+static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr,
+ unsigned long len, int prot, unsigned long bits)
+{
+ unsigned long vmaddr;
+ spinlock_t *ptl;
+ pte_t *ptep;
+ int rc;
+
+ while (len) {
+ rc = -EAGAIN;
+ ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
+ if (ptep) {
+ rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, bits);
+ gmap_pte_op_end(ptl);
+ }
+ if (rc) {
+ vmaddr = __gmap_translate(gmap, gaddr);
+ if (IS_ERR_VALUE(vmaddr))
+ return vmaddr;
+ rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
+ if (rc)
+ return rc;
+ continue;
+ }
+ gaddr += PAGE_SIZE;
+ len -= PAGE_SIZE;
+ }
+ return 0;
+}
+
/**
* gmap_mprotect_notify - change access rights for a range of ptes and
* call the notifier if any pte changes again
@@ -752,61 +901,1012 @@ static void gmap_pte_op_end(spinlock_t *ptl)
int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr,
unsigned long len, int prot)
{
- unsigned long vmaddr;
- spinlock_t *ptl;
- pte_t *ptep;
- int rc = 0;
+ int rc;
- if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK))
+ if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK) || gmap_is_shadow(gmap))
return -EINVAL;
if (!MACHINE_HAS_ESOP && prot == PROT_READ)
return -EINVAL;
down_read(&gmap->mm->mmap_sem);
- while (len) {
+ rc = gmap_protect_range(gmap, gaddr, len, prot, PGSTE_IN_BIT);
+ up_read(&gmap->mm->mmap_sem);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_mprotect_notify);
+
+/**
+ * gmap_read_table - get an unsigned long value from a guest page table using
+ * absolute addressing, without marking the page referenced.
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @val: pointer to the unsigned long value to return
+ *
+ * Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT
+ * if reading using the virtual address failed.
+ *
+ * Called with gmap->mm->mmap_sem in read.
+ */
+int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val)
+{
+ unsigned long address, vmaddr;
+ spinlock_t *ptl;
+ pte_t *ptep, pte;
+ int rc;
+
+ while (1) {
rc = -EAGAIN;
ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
if (ptep) {
- rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot);
+ pte = *ptep;
+ if (pte_present(pte) && (pte_val(pte) & _PAGE_READ)) {
+ address = pte_val(pte) & PAGE_MASK;
+ address += gaddr & ~PAGE_MASK;
+ *val = *(unsigned long *) address;
+ pte_val(*ptep) |= _PAGE_YOUNG;
+ /* Do *NOT* clear the _PAGE_INVALID bit! */
+ rc = 0;
+ }
+ gmap_pte_op_end(ptl);
+ }
+ if (!rc)
+ break;
+ vmaddr = __gmap_translate(gmap, gaddr);
+ if (IS_ERR_VALUE(vmaddr)) {
+ rc = vmaddr;
+ break;
+ }
+ rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
+ if (rc)
+ break;
+ }
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_read_table);
+
+/**
+ * gmap_insert_rmap - add a rmap to the host_to_rmap radix tree
+ * @sg: pointer to the shadow guest address space structure
+ * @vmaddr: vm address associated with the rmap
+ * @rmap: pointer to the rmap structure
+ *
+ * Called with the sg->guest_table_lock
+ */
+static inline void gmap_insert_rmap(struct gmap *sg, unsigned long vmaddr,
+ struct gmap_rmap *rmap)
+{
+ void **slot;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ slot = radix_tree_lookup_slot(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT);
+ if (slot) {
+ rmap->next = radix_tree_deref_slot_protected(slot,
+ &sg->guest_table_lock);
+ radix_tree_replace_slot(slot, rmap);
+ } else {
+ rmap->next = NULL;
+ radix_tree_insert(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT,
+ rmap);
+ }
+}
+
+/**
+ * gmap_protect_rmap - modify access rights to memory and create an rmap
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow gmap
+ * @paddr: address in the parent guest address space
+ * @len: length of the memory area to protect
+ * @prot: indicates access rights: none, read-only or read-write
+ *
+ * Returns 0 if successfully protected and the rmap was created, -ENOMEM
+ * if out of memory and -EFAULT if paddr is invalid.
+ */
+static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr,
+ unsigned long paddr, unsigned long len, int prot)
+{
+ struct gmap *parent;
+ struct gmap_rmap *rmap;
+ unsigned long vmaddr;
+ spinlock_t *ptl;
+ pte_t *ptep;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ parent = sg->parent;
+ while (len) {
+ vmaddr = __gmap_translate(parent, paddr);
+ if (IS_ERR_VALUE(vmaddr))
+ return vmaddr;
+ rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
+ if (!rmap)
+ return -ENOMEM;
+ rmap->raddr = raddr;
+ rc = radix_tree_preload(GFP_KERNEL);
+ if (rc) {
+ kfree(rmap);
+ return rc;
+ }
+ rc = -EAGAIN;
+ ptep = gmap_pte_op_walk(parent, paddr, &ptl);
+ if (ptep) {
+ spin_lock(&sg->guest_table_lock);
+ rc = ptep_force_prot(parent->mm, paddr, ptep, prot,
+ PGSTE_VSIE_BIT);
+ if (!rc)
+ gmap_insert_rmap(sg, vmaddr, rmap);
+ spin_unlock(&sg->guest_table_lock);
gmap_pte_op_end(ptl);
}
+ radix_tree_preload_end();
if (rc) {
- vmaddr = __gmap_translate(gmap, gaddr);
- if (IS_ERR_VALUE(vmaddr)) {
- rc = vmaddr;
- break;
- }
- rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
+ kfree(rmap);
+ rc = gmap_pte_op_fixup(parent, paddr, vmaddr);
if (rc)
- break;
+ return rc;
continue;
}
- gaddr += PAGE_SIZE;
+ paddr += PAGE_SIZE;
len -= PAGE_SIZE;
}
- up_read(&gmap->mm->mmap_sem);
+ return 0;
+}
+
+#define _SHADOW_RMAP_MASK 0x7
+#define _SHADOW_RMAP_REGION1 0x5
+#define _SHADOW_RMAP_REGION2 0x4
+#define _SHADOW_RMAP_REGION3 0x3
+#define _SHADOW_RMAP_SEGMENT 0x2
+#define _SHADOW_RMAP_PGTABLE 0x1
+
+/**
+ * gmap_idte_one - invalidate a single region or segment table entry
+ * @asce: region or segment table *origin* + table-type bits
+ * @vaddr: virtual address to identify the table entry to flush
+ *
+ * The invalid bit of a single region or segment table entry is set
+ * and the associated TLB entries depending on the entry are flushed.
+ * The table-type of the @asce identifies the portion of the @vaddr
+ * that is used as the invalidation index.
+ */
+static inline void gmap_idte_one(unsigned long asce, unsigned long vaddr)
+{
+ asm volatile(
+ " .insn rrf,0xb98e0000,%0,%1,0,0"
+ : : "a" (asce), "a" (vaddr) : "cc", "memory");
+}
+
+/**
+ * gmap_unshadow_page - remove a page from a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_page(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long *table;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ table = gmap_table_walk(sg, raddr, 0); /* get page table pointer */
+ if (!table || *table & _PAGE_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 12) - 1);
+ ptep_unshadow_pte(sg->mm, raddr, (pte_t *) table);
+}
+
+/**
+ * __gmap_unshadow_pgt - remove all entries from a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @pgt: pointer to the start of a shadow page table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr,
+ unsigned long *pgt)
+{
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ for (i = 0; i < 256; i++, raddr += 1UL << 12)
+ pgt[i] = _PAGE_INVALID;
+}
+
+/**
+ * gmap_unshadow_pgt - remove a shadow page table from a segment entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long sto, *ste, *pgt;
+ struct page *page;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */
+ if (!ste || *ste & _SEGMENT_ENTRY_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 20) - 1);
+ sto = (unsigned long) (ste - ((raddr >> 20) & 0x7ff));
+ gmap_idte_one(sto | _ASCE_TYPE_SEGMENT, raddr);
+ pgt = (unsigned long *)(*ste & _SEGMENT_ENTRY_ORIGIN);
+ *ste = _SEGMENT_ENTRY_EMPTY;
+ __gmap_unshadow_pgt(sg, raddr, pgt);
+ /* Free page table */
+ page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ page_table_free_pgste(page);
+}
+
+/**
+ * __gmap_unshadow_sgt - remove all entries from a shadow segment table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @sgt: pointer to the start of a shadow segment table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr,
+ unsigned long *sgt)
+{
+ unsigned long asce, *pgt;
+ struct page *page;
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ asce = (unsigned long) sgt | _ASCE_TYPE_SEGMENT;
+ for (i = 0; i < 2048; i++, raddr += 1UL << 20) {
+ if (sgt[i] & _SEGMENT_ENTRY_INVALID)
+ continue;
+ pgt = (unsigned long *)(sgt[i] & _REGION_ENTRY_ORIGIN);
+ sgt[i] = _SEGMENT_ENTRY_EMPTY;
+ __gmap_unshadow_pgt(sg, raddr, pgt);
+ /* Free page table */
+ page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ page_table_free_pgste(page);
+ }
+}
+
+/**
+ * gmap_unshadow_sgt - remove a shadow segment table from a region-3 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the shadow->guest_table_lock
+ */
+static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long r3o, *r3e, *sgt;
+ struct page *page;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */
+ if (!r3e || *r3e & _REGION_ENTRY_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 31) - 1);
+ r3o = (unsigned long) (r3e - ((raddr >> 31) & 0x7ff));
+ gmap_idte_one(r3o | _ASCE_TYPE_REGION3, raddr);
+ sgt = (unsigned long *)(*r3e & _REGION_ENTRY_ORIGIN);
+ *r3e = _REGION3_ENTRY_EMPTY;
+ __gmap_unshadow_sgt(sg, raddr, sgt);
+ /* Free segment table */
+ page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r3t - remove all entries from a shadow region-3 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: address in the shadow guest address space
+ * @r3t: pointer to the start of a shadow region-3 table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr,
+ unsigned long *r3t)
+{
+ unsigned long asce, *sgt;
+ struct page *page;
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ asce = (unsigned long) r3t | _ASCE_TYPE_REGION3;
+ for (i = 0; i < 2048; i++, raddr += 1UL << 31) {
+ if (r3t[i] & _REGION_ENTRY_INVALID)
+ continue;
+ sgt = (unsigned long *)(r3t[i] & _REGION_ENTRY_ORIGIN);
+ r3t[i] = _REGION3_ENTRY_EMPTY;
+ __gmap_unshadow_sgt(sg, raddr, sgt);
+ /* Free segment table */
+ page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+ }
+}
+
+/**
+ * gmap_unshadow_r3t - remove a shadow region-3 table from a region-2 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long r2o, *r2e, *r3t;
+ struct page *page;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */
+ if (!r2e || *r2e & _REGION_ENTRY_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 42) - 1);
+ r2o = (unsigned long) (r2e - ((raddr >> 42) & 0x7ff));
+ gmap_idte_one(r2o | _ASCE_TYPE_REGION2, raddr);
+ r3t = (unsigned long *)(*r2e & _REGION_ENTRY_ORIGIN);
+ *r2e = _REGION2_ENTRY_EMPTY;
+ __gmap_unshadow_r3t(sg, raddr, r3t);
+ /* Free region 3 table */
+ page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r2t - remove all entries from a shadow region-2 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @r2t: pointer to the start of a shadow region-2 table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr,
+ unsigned long *r2t)
+{
+ unsigned long asce, *r3t;
+ struct page *page;
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ asce = (unsigned long) r2t | _ASCE_TYPE_REGION2;
+ for (i = 0; i < 2048; i++, raddr += 1UL << 42) {
+ if (r2t[i] & _REGION_ENTRY_INVALID)
+ continue;
+ r3t = (unsigned long *)(r2t[i] & _REGION_ENTRY_ORIGIN);
+ r2t[i] = _REGION2_ENTRY_EMPTY;
+ __gmap_unshadow_r3t(sg, raddr, r3t);
+ /* Free region 3 table */
+ page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+ }
+}
+
+/**
+ * gmap_unshadow_r2t - remove a shadow region-2 table from a region-1 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long r1o, *r1e, *r2t;
+ struct page *page;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */
+ if (!r1e || *r1e & _REGION_ENTRY_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 53) - 1);
+ r1o = (unsigned long) (r1e - ((raddr >> 53) & 0x7ff));
+ gmap_idte_one(r1o | _ASCE_TYPE_REGION1, raddr);
+ r2t = (unsigned long *)(*r1e & _REGION_ENTRY_ORIGIN);
+ *r1e = _REGION1_ENTRY_EMPTY;
+ __gmap_unshadow_r2t(sg, raddr, r2t);
+ /* Free region 2 table */
+ page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r1t - remove all entries from a shadow region-1 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @r1t: pointer to the start of a shadow region-1 table
+ *
+ * Called with the shadow->guest_table_lock
+ */
+static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr,
+ unsigned long *r1t)
+{
+ unsigned long asce, *r2t;
+ struct page *page;
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ asce = (unsigned long) r1t | _ASCE_TYPE_REGION1;
+ for (i = 0; i < 2048; i++, raddr += 1UL << 53) {
+ if (r1t[i] & _REGION_ENTRY_INVALID)
+ continue;
+ r2t = (unsigned long *)(r1t[i] & _REGION_ENTRY_ORIGIN);
+ __gmap_unshadow_r2t(sg, raddr, r2t);
+ /* Clear entry and flush translation r1t -> r2t */
+ gmap_idte_one(asce, raddr);
+ r1t[i] = _REGION1_ENTRY_EMPTY;
+ /* Free region 2 table */
+ page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+ }
+}
+
+/**
+ * gmap_unshadow - remove a shadow page table completely
+ * @sg: pointer to the shadow guest address space structure
+ *
+ * Called with sg->guest_table_lock
+ */
+static void gmap_unshadow(struct gmap *sg)
+{
+ unsigned long *table;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ if (sg->removed)
+ return;
+ sg->removed = 1;
+ gmap_call_notifier(sg, 0, -1UL);
+ table = (unsigned long *)(sg->asce & _ASCE_ORIGIN);
+ switch (sg->asce & _ASCE_TYPE_MASK) {
+ case _ASCE_TYPE_REGION1:
+ __gmap_unshadow_r1t(sg, 0, table);
+ break;
+ case _ASCE_TYPE_REGION2:
+ __gmap_unshadow_r2t(sg, 0, table);
+ break;
+ case _ASCE_TYPE_REGION3:
+ __gmap_unshadow_r3t(sg, 0, table);
+ break;
+ case _ASCE_TYPE_SEGMENT:
+ __gmap_unshadow_sgt(sg, 0, table);
+ break;
+ }
+}
+
+/**
+ * gmap_find_shadow - find a specific asce in the list of shadow tables
+ * @parent: pointer to the parent gmap
+ * @asce: ASCE for which the shadow table is created
+ *
+ * Returns the pointer to a gmap if a shadow table with the given asce is
+ * already available, otherwise NULL
+ */
+static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
+{
+ struct gmap *sg;
+
+ list_for_each_entry(sg, &parent->children, list) {
+ if (sg->orig_asce != asce || sg->removed)
+ continue;
+ atomic_inc(&sg->ref_count);
+ return sg;
+ }
+ return NULL;
+}
+
+/**
+ * gmap_shadow - create/find a shadow guest address space
+ * @parent: pointer to the parent gmap
+ * @asce: ASCE for which the shadow table is created
+ *
+ * The pages of the top level page table referred by the asce parameter
+ * will be set to read-only and marked in the PGSTEs of the kvm process.
+ * The shadow table will be removed automatically on any change to the
+ * PTE mapping for the source table.
+ *
+ * Returns a guest address space structure, NULL if out of memory or if
+ * anything goes wrong while protecting the top level pages.
+ */
+struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce)
+{
+ struct gmap *sg, *new;
+ unsigned long limit;
+ int rc;
+
+ BUG_ON(gmap_is_shadow(parent));
+ spin_lock(&parent->shadow_lock);
+ sg = gmap_find_shadow(parent, asce);
+ spin_unlock(&parent->shadow_lock);
+ if (sg)
+ return sg;
+ /* Create a new shadow gmap */
+ limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11));
+ new = gmap_alloc(limit);
+ if (!new)
+ return NULL;
+ new->mm = parent->mm;
+ new->parent = gmap_get(parent);
+ new->orig_asce = asce;
+ down_read(&parent->mm->mmap_sem);
+ rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN,
+ ((asce & _ASCE_TABLE_LENGTH) + 1) * 4096,
+ PROT_READ, PGSTE_VSIE_BIT);
+ up_read(&parent->mm->mmap_sem);
+ if (rc) {
+ atomic_set(&new->ref_count, 2);
+ spin_lock(&parent->shadow_lock);
+ /* Recheck if another CPU created the same shadow */
+ sg = gmap_find_shadow(parent, asce);
+ if (!sg) {
+ list_add(&new->list, &parent->children);
+ sg = new;
+ new = NULL;
+ }
+ spin_unlock(&parent->shadow_lock);
+ }
+ if (new)
+ gmap_free(new);
+ return sg;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow);
+
+/**
+ * gmap_shadow_r2t - create an empty shadow region 2 table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @r2t: parent gmap address of the region 2 table to get shadowed
+ *
+ * The r2t parameter specifies the address of the source table. The
+ * four pages of the source table are made read-only in the parent gmap
+ * address space. A write to the source table area @r2t will automatically
+ * remove the shadow r2 table and all of its decendents.
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
+{
+ unsigned long raddr, origin, offset, len;
+ unsigned long *s_r2t, *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ /* Allocate a shadow region second table */
+ page = alloc_pages(GFP_KERNEL, 2);
+ if (!page)
+ return -ENOMEM;
+ page->index = r2t & _REGION_ENTRY_ORIGIN;
+ s_r2t = (unsigned long *) page_to_phys(page);
+ /* Install shadow region second table */
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */
+ if (!table) {
+ rc = -EAGAIN; /* Race with unshadow */
+ goto out_free;
+ }
+ if (!(*table & _REGION_ENTRY_INVALID)) {
+ rc = 0; /* Already established */
+ goto out_free;
+ }
+ crst_table_init(s_r2t, _REGION2_ENTRY_EMPTY);
+ *table = (unsigned long) s_r2t |
+ _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R1;
+ list_add(&page->lru, &sg->crst_list);
+ spin_unlock(&sg->guest_table_lock);
+ /* Make r2t read-only in parent gmap page table */
+ raddr = (saddr & 0xffe0000000000000UL) | _SHADOW_RMAP_REGION1;
+ origin = r2t & _REGION_ENTRY_ORIGIN;
+ offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+ len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+ rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+ if (rc) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow_r2t(sg, raddr);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ return rc;
+out_free:
+ spin_unlock(&sg->guest_table_lock);
+ __free_pages(page, 2);
return rc;
}
-EXPORT_SYMBOL_GPL(gmap_mprotect_notify);
+EXPORT_SYMBOL_GPL(gmap_shadow_r2t);
+
+/**
+ * gmap_shadow_r3t - create a shadow region 3 table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @r3t: parent gmap address of the region 3 table to get shadowed
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
+{
+ unsigned long raddr, origin, offset, len;
+ unsigned long *s_r3t, *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ /* Allocate a shadow region second table */
+ page = alloc_pages(GFP_KERNEL, 2);
+ if (!page)
+ return -ENOMEM;
+ page->index = r3t & _REGION_ENTRY_ORIGIN;
+ s_r3t = (unsigned long *) page_to_phys(page);
+ /* Install shadow region second table */
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */
+ if (!table) {
+ rc = -EAGAIN; /* Race with unshadow */
+ goto out_free;
+ }
+ if (!(*table & _REGION_ENTRY_INVALID)) {
+ rc = 0; /* Already established */
+ goto out_free;
+ }
+ crst_table_init(s_r3t, _REGION3_ENTRY_EMPTY);
+ *table = (unsigned long) s_r3t |
+ _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R2;
+ list_add(&page->lru, &sg->crst_list);
+ spin_unlock(&sg->guest_table_lock);
+ /* Make r3t read-only in parent gmap page table */
+ raddr = (saddr & 0xfffffc0000000000UL) | _SHADOW_RMAP_REGION2;
+ origin = r3t & _REGION_ENTRY_ORIGIN;
+ offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+ len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+ rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+ if (rc) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow_r3t(sg, raddr);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ return rc;
+out_free:
+ spin_unlock(&sg->guest_table_lock);
+ __free_pages(page, 2);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_r3t);
+
+/**
+ * gmap_shadow_sgt - create a shadow segment table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @sgt: parent gmap address of the segment table to get shadowed
+ *
+ * Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt)
+{
+ unsigned long raddr, origin, offset, len;
+ unsigned long *s_sgt, *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ /* Allocate a shadow segment table */
+ page = alloc_pages(GFP_KERNEL, 2);
+ if (!page)
+ return -ENOMEM;
+ page->index = sgt & _REGION_ENTRY_ORIGIN;
+ s_sgt = (unsigned long *) page_to_phys(page);
+ /* Install shadow region second table */
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */
+ if (!table) {
+ rc = -EAGAIN; /* Race with unshadow */
+ goto out_free;
+ }
+ if (!(*table & _REGION_ENTRY_INVALID)) {
+ rc = 0; /* Already established */
+ goto out_free;
+ }
+ crst_table_init(s_sgt, _SEGMENT_ENTRY_EMPTY);
+ *table = (unsigned long) s_sgt |
+ _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R3;
+ list_add(&page->lru, &sg->crst_list);
+ spin_unlock(&sg->guest_table_lock);
+ /* Make sgt read-only in parent gmap page table */
+ raddr = (saddr & 0xffffffff80000000UL) | _SHADOW_RMAP_REGION3;
+ origin = sgt & _REGION_ENTRY_ORIGIN;
+ offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+ len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+ rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+ if (rc) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow_sgt(sg, raddr);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ return rc;
+out_free:
+ spin_unlock(&sg->guest_table_lock);
+ __free_pages(page, 2);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_sgt);
+
+/**
+ * gmap_shadow_lookup_pgtable - find a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: the address in the shadow aguest address space
+ * @pgt: parent gmap address of the page table to get shadowed
+ * @dat_protection: if the pgtable is marked as protected by dat
+ *
+ * Returns 0 if the shadow page table was found and -EAGAIN if the page
+ * table was not found.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
+ unsigned long *pgt, int *dat_protection)
+{
+ unsigned long *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
+ if (table && !(*table & _SEGMENT_ENTRY_INVALID)) {
+ /* Shadow page tables are full pages (pte+pgste) */
+ page = pfn_to_page(*table >> PAGE_SHIFT);
+ *pgt = page->index;
+ *dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT);
+ rc = 0;
+ } else {
+ rc = -EAGAIN;
+ }
+ spin_unlock(&sg->guest_table_lock);
+ return rc;
+
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup);
+
+/**
+ * gmap_shadow_pgt - instantiate a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @pgt: parent gmap address of the page table to get shadowed
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory,
+ * -EFAULT if an address in the parent gmap could not be resolved and
+ *
+ * Called with gmap->mm->mmap_sem in read
+ */
+int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt)
+{
+ unsigned long raddr, origin;
+ unsigned long *s_pgt, *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ /* Allocate a shadow page table */
+ page = page_table_alloc_pgste(sg->mm);
+ if (!page)
+ return -ENOMEM;
+ page->index = pgt & _SEGMENT_ENTRY_ORIGIN;
+ s_pgt = (unsigned long *) page_to_phys(page);
+ /* Install shadow page table */
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
+ if (!table) {
+ rc = -EAGAIN; /* Race with unshadow */
+ goto out_free;
+ }
+ if (!(*table & _SEGMENT_ENTRY_INVALID)) {
+ rc = 0; /* Already established */
+ goto out_free;
+ }
+ *table = (unsigned long) s_pgt | _SEGMENT_ENTRY |
+ (pgt & _SEGMENT_ENTRY_PROTECT);
+ list_add(&page->lru, &sg->pt_list);
+ spin_unlock(&sg->guest_table_lock);
+ /* Make pgt read-only in parent gmap page table (not the pgste) */
+ raddr = (saddr & 0xfffffffffff00000UL) | _SHADOW_RMAP_SEGMENT;
+ origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK;
+ rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ);
+ if (rc) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow_pgt(sg, raddr);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ return rc;
+out_free:
+ spin_unlock(&sg->guest_table_lock);
+ page_table_free_pgste(page);
+ return rc;
+
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_pgt);
+
+/**
+ * gmap_shadow_page - create a shadow page mapping
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @paddr: parent gmap address to get mapped at @saddr
+ * @write: =1 map r/w, =0 map r/o
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
+ unsigned long paddr, int write)
+{
+ struct gmap *parent;
+ struct gmap_rmap *rmap;
+ unsigned long vmaddr;
+ spinlock_t *ptl;
+ pte_t *sptep, *tptep;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ parent = sg->parent;
+
+ rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
+ if (!rmap)
+ return -ENOMEM;
+ rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE;
+
+ while (1) {
+ vmaddr = __gmap_translate(parent, paddr);
+ if (IS_ERR_VALUE(vmaddr)) {
+ rc = vmaddr;
+ break;
+ }
+ rc = radix_tree_preload(GFP_KERNEL);
+ if (rc)
+ break;
+ rc = -EAGAIN;
+ sptep = gmap_pte_op_walk(parent, paddr, &ptl);
+ if (sptep) {
+ spin_lock(&sg->guest_table_lock);
+ /* Get page table pointer */
+ tptep = (pte_t *) gmap_table_walk(sg, saddr, 0);
+ if (!tptep) {
+ spin_unlock(&sg->guest_table_lock);
+ gmap_pte_op_end(ptl);
+ radix_tree_preload_end();
+ break;
+ }
+ rc = ptep_shadow_pte(sg->mm, saddr,
+ sptep, tptep, write);
+ if (rc > 0) {
+ /* Success and a new mapping */
+ gmap_insert_rmap(sg, vmaddr, rmap);
+ rmap = NULL;
+ rc = 0;
+ }
+ gmap_pte_op_end(ptl);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ radix_tree_preload_end();
+ if (!rc)
+ break;
+ rc = gmap_pte_op_fixup(parent, paddr, vmaddr);
+ if (rc)
+ break;
+ }
+ kfree(rmap);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_page);
+
+/**
+ * gmap_shadow_notify - handle notifications for shadow gmap
+ *
+ * Called with sg->parent->shadow_lock.
+ */
+static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr,
+ unsigned long offset, pte_t *pte)
+{
+ struct gmap_rmap *rmap, *rnext, *head;
+ unsigned long gaddr, start, end, bits, raddr;
+ unsigned long *table;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ spin_lock(&sg->parent->guest_table_lock);
+ table = radix_tree_lookup(&sg->parent->host_to_guest,
+ vmaddr >> PMD_SHIFT);
+ gaddr = table ? __gmap_segment_gaddr(table) + offset : 0;
+ spin_unlock(&sg->parent->guest_table_lock);
+ if (!table)
+ return;
+
+ spin_lock(&sg->guest_table_lock);
+ if (sg->removed) {
+ spin_unlock(&sg->guest_table_lock);
+ return;
+ }
+ /* Check for top level table */
+ start = sg->orig_asce & _ASCE_ORIGIN;
+ end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * 4096;
+ if (gaddr >= start && gaddr < end) {
+ /* The complete shadow table has to go */
+ gmap_unshadow(sg);
+ spin_unlock(&sg->guest_table_lock);
+ list_del(&sg->list);
+ gmap_put(sg);
+ return;
+ }
+ /* Remove the page table tree from on specific entry */
+ head = radix_tree_delete(&sg->host_to_rmap, vmaddr >> 12);
+ gmap_for_each_rmap_safe(rmap, rnext, head) {
+ bits = rmap->raddr & _SHADOW_RMAP_MASK;
+ raddr = rmap->raddr ^ bits;
+ switch (bits) {
+ case _SHADOW_RMAP_REGION1:
+ gmap_unshadow_r2t(sg, raddr);
+ break;
+ case _SHADOW_RMAP_REGION2:
+ gmap_unshadow_r3t(sg, raddr);
+ break;
+ case _SHADOW_RMAP_REGION3:
+ gmap_unshadow_sgt(sg, raddr);
+ break;
+ case _SHADOW_RMAP_SEGMENT:
+ gmap_unshadow_pgt(sg, raddr);
+ break;
+ case _SHADOW_RMAP_PGTABLE:
+ gmap_unshadow_page(sg, raddr);
+ break;
+ }
+ kfree(rmap);
+ }
+ spin_unlock(&sg->guest_table_lock);
+}
/**
* ptep_notify - call all invalidation callbacks for a specific pte.
* @mm: pointer to the process mm_struct
* @addr: virtual address in the process address space
* @pte: pointer to the page table entry
+ * @bits: bits from the pgste that caused the notify call
*
* This function is assumed to be called with the page table lock held
* for the pte to notify.
*/
-void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, pte_t *pte)
+void ptep_notify(struct mm_struct *mm, unsigned long vmaddr,
+ pte_t *pte, unsigned long bits)
{
unsigned long offset, gaddr;
unsigned long *table;
- struct gmap *gmap;
+ struct gmap *gmap, *sg, *next;
offset = ((unsigned long) pte) & (255 * sizeof(pte_t));
offset = offset * (4096 / sizeof(pte_t));
rcu_read_lock();
list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
+ if (!list_empty(&gmap->children) && (bits & PGSTE_VSIE_BIT)) {
+ spin_lock(&gmap->shadow_lock);
+ list_for_each_entry_safe(sg, next,
+ &gmap->children, list)
+ gmap_shadow_notify(sg, vmaddr, offset, pte);
+ spin_unlock(&gmap->shadow_lock);
+ }
+ if (!(bits & PGSTE_IN_BIT))
+ continue;
spin_lock(&gmap->guest_table_lock);
table = radix_tree_lookup(&gmap->host_to_guest,
vmaddr >> PMD_SHIFT);
diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c
index 7be1f94f70a8..9c57a295a045 100644
--- a/arch/s390/mm/pgalloc.c
+++ b/arch/s390/mm/pgalloc.c
@@ -137,6 +137,29 @@ static inline unsigned int atomic_xor_bits(atomic_t *v, unsigned int bits)
return new;
}
+#ifdef CONFIG_PGSTE
+
+struct page *page_table_alloc_pgste(struct mm_struct *mm)
+{
+ struct page *page;
+ unsigned long *table;
+
+ page = alloc_page(GFP_KERNEL|__GFP_REPEAT);
+ if (page) {
+ table = (unsigned long *) page_to_phys(page);
+ clear_table(table, _PAGE_INVALID, PAGE_SIZE/2);
+ clear_table(table + PTRS_PER_PTE, 0, PAGE_SIZE/2);
+ }
+ return page;
+}
+
+void page_table_free_pgste(struct page *page)
+{
+ __free_page(page);
+}
+
+#endif /* CONFIG_PGSTE */
+
/*
* page table entry allocation/free routines.
*/
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index ab65fb11e058..5b02583fbf4c 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -184,9 +184,12 @@ static inline pgste_t pgste_pte_notify(struct mm_struct *mm,
pte_t *ptep, pgste_t pgste)
{
#ifdef CONFIG_PGSTE
- if (pgste_val(pgste) & PGSTE_IN_BIT) {
- pgste_val(pgste) &= ~PGSTE_IN_BIT;
- ptep_notify(mm, addr, ptep);
+ unsigned long bits;
+
+ bits = pgste_val(pgste) & (PGSTE_IN_BIT | PGSTE_VSIE_BIT);
+ if (bits) {
+ pgste_val(pgste) ^= bits;
+ ptep_notify(mm, addr, ptep, bits);
}
#endif
return pgste;
@@ -420,12 +423,13 @@ void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
* @addr: virtual address in the guest address space
* @ptep: pointer to the page table entry
* @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ * @bit: pgste bit to set (e.g. for notification)
*
* Returns 0 if the access rights were changed and -EAGAIN if the current
* and requested access rights are incompatible.
*/
int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, int prot)
+ pte_t *ptep, int prot, unsigned long bit)
{
pte_t entry;
pgste_t pgste;
@@ -441,7 +445,7 @@ int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
pgste_set_unlock(ptep, pgste);
return -EAGAIN;
}
- /* Change access rights and set the pgste notification bit */
+ /* Change access rights and set pgste bit */
if (prot == PROT_NONE && !pte_i) {
ptep_flush_direct(mm, addr, ptep);
pgste = pgste_update_all(entry, pgste, mm);
@@ -452,12 +456,53 @@ int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
pte_val(entry) &= ~_PAGE_INVALID;
pte_val(entry) |= _PAGE_PROTECT;
}
- pgste_val(pgste) |= PGSTE_IN_BIT;
+ pgste_val(pgste) |= bit;
pgste = pgste_set_pte(ptep, pgste, entry);
pgste_set_unlock(ptep, pgste);
return 0;
}
+int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
+ pte_t *sptep, pte_t *tptep, int write)
+{
+ pgste_t spgste, tpgste;
+ pte_t spte, tpte;
+ int rc = -EAGAIN;
+
+ spgste = pgste_get_lock(sptep);
+ spte = *sptep;
+ if (!(pte_val(spte) & _PAGE_INVALID) &&
+ !(pte_val(spte) & _PAGE_PROTECT)) {
+ rc = 0;
+ if (!(pte_val(*tptep) & _PAGE_INVALID))
+ /* Update existing mapping */
+ ptep_flush_direct(mm, saddr, tptep);
+ else
+ rc = 1;
+ pgste_val(spgste) |= PGSTE_VSIE_BIT;
+ tpgste = pgste_get_lock(tptep);
+ pte_val(tpte) = (pte_val(spte) & PAGE_MASK) |
+ (write ? 0 : _PAGE_PROTECT);
+ /* don't touch the storage key - it belongs to parent pgste */
+ tpgste = pgste_set_pte(tptep, tpgste, tpte);
+ pgste_set_unlock(tptep, tpgste);
+ }
+ pgste_set_unlock(sptep, spgste);
+ return rc;
+}
+
+void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep)
+{
+ pgste_t pgste;
+
+ pgste = pgste_get_lock(ptep);
+ /* notifier is called by the caller */
+ ptep_flush_direct(mm, saddr, ptep);
+ /* don't touch the storage key - it belongs to parent pgste */
+ pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID));
+ pgste_set_unlock(ptep, pgste);
+}
+
static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry)
{
if (!non_swap_entry(entry))
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-13 21:38:26 +0000