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[Xen-devel] [PATCH v4 26/31] x86/mm: move pv_{alloc, free}_page_type



Move them and the helper functions to pv/mm.c.  Use bool in the moved
code where appropriate.

Put BUG() in the stub because the callers will call BUG or BUG_ON
anyway.

Signed-off-by: Wei Liu <wei.liu2@xxxxxxxxxx>
---
v4: add BUG() in stubs
---
 xen/arch/x86/domain.c       |   1 +
 xen/arch/x86/mm.c           | 492 --------------------------------------------
 xen/arch/x86/pv/mm.c        | 491 +++++++++++++++++++++++++++++++++++++++++++
 xen/include/asm-x86/mm.h    |   3 -
 xen/include/asm-x86/pv/mm.h |  14 ++
 5 files changed, 506 insertions(+), 495 deletions(-)

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 8fae38485c..e79a7de7e4 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -64,6 +64,7 @@
 #include <compat/vcpu.h>
 #include <asm/psr.h>
 #include <asm/pv/domain.h>
+#include <asm/pv/mm.h>
 #include <asm/pv/processor.h>
 
 DEFINE_PER_CPU(struct vcpu *, curr_vcpu);
diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
index 590e7ae65b..204c20d6fd 100644
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -510,21 +510,6 @@ static void invalidate_shadow_ldt(struct vcpu *v, int 
flush)
 }
 
 
-static int alloc_segdesc_page(struct page_info *page)
-{
-    const struct domain *owner = page_get_owner(page);
-    struct desc_struct *descs = __map_domain_page(page);
-    unsigned i;
-
-    for ( i = 0; i < 512; i++ )
-        if ( unlikely(!check_descriptor(owner, &descs[i])) )
-            break;
-
-    unmap_domain_page(descs);
-
-    return i == 512 ? 0 : -EINVAL;
-}
-
 bool get_page_from_mfn(mfn_t mfn, struct domain *d)
 {
     struct page_info *page = mfn_to_page(mfn_x(mfn));
@@ -539,7 +524,6 @@ bool get_page_from_mfn(mfn_t mfn, struct domain *d)
     return true;
 }
 
-
 int get_page_and_type_from_mfn(mfn_t mfn, unsigned long type, struct domain *d,
                                int partial, bool preemptible)
 {
@@ -1165,172 +1149,6 @@ int put_page_from_l4e(l4_pgentry_t l4e, unsigned long 
pfn, int partial,
     return 1;
 }
 
-static int alloc_l1_table(struct page_info *page)
-{
-    struct domain *d = page_get_owner(page);
-    unsigned long  pfn = page_to_mfn(page);
-    l1_pgentry_t  *pl1e;
-    unsigned int   i;
-    int            ret = 0;
-
-    pl1e = map_domain_page(_mfn(pfn));
-
-    for ( i = 0; i < L1_PAGETABLE_ENTRIES; i++ )
-    {
-        switch ( ret = get_page_from_l1e(pl1e[i], d, d) )
-        {
-        default:
-            goto fail;
-        case 0:
-            break;
-        case _PAGE_RW ... _PAGE_RW | PAGE_CACHE_ATTRS:
-            ASSERT(!(ret & ~(_PAGE_RW | PAGE_CACHE_ATTRS)));
-            l1e_flip_flags(pl1e[i], ret);
-            break;
-        }
-
-        adjust_guest_l1e(pl1e[i], d);
-    }
-
-    unmap_domain_page(pl1e);
-    return 0;
-
- fail:
-    gdprintk(XENLOG_WARNING, "Failure in alloc_l1_table: slot %#x\n", i);
-    while ( i-- > 0 )
-        put_page_from_l1e(pl1e[i], d);
-
-    unmap_domain_page(pl1e);
-    return ret;
-}
-
-static int alloc_l2_table(struct page_info *page, unsigned long type,
-                          int preemptible)
-{
-    struct domain *d = page_get_owner(page);
-    unsigned long  pfn = page_to_mfn(page);
-    l2_pgentry_t  *pl2e;
-    unsigned int   i;
-    int            rc = 0;
-
-    pl2e = map_domain_page(_mfn(pfn));
-
-    for ( i = page->nr_validated_ptes; i < L2_PAGETABLE_ENTRIES; i++ )
-    {
-        if ( preemptible && i > page->nr_validated_ptes
-             && hypercall_preempt_check() )
-        {
-            page->nr_validated_ptes = i;
-            rc = -ERESTART;
-            break;
-        }
-
-        if ( !is_guest_l2_slot(d, type, i) ||
-             (rc = get_page_from_l2e(pl2e[i], pfn, d)) > 0 )
-            continue;
-
-        if ( rc < 0 )
-        {
-            gdprintk(XENLOG_WARNING, "Failure in alloc_l2_table: slot %#x\n", 
i);
-            while ( i-- > 0 )
-                if ( is_guest_l2_slot(d, type, i) )
-                    put_page_from_l2e(pl2e[i], pfn);
-            break;
-        }
-
-        adjust_guest_l2e(pl2e[i], d);
-    }
-
-    if ( rc >= 0 && (type & PGT_pae_xen_l2) )
-    {
-        /* Xen private mappings. */
-        memcpy(&pl2e[COMPAT_L2_PAGETABLE_FIRST_XEN_SLOT(d)],
-               &compat_idle_pg_table_l2[
-                   l2_table_offset(HIRO_COMPAT_MPT_VIRT_START)],
-               COMPAT_L2_PAGETABLE_XEN_SLOTS(d) * sizeof(*pl2e));
-    }
-
-    unmap_domain_page(pl2e);
-    return rc > 0 ? 0 : rc;
-}
-
-static int alloc_l3_table(struct page_info *page)
-{
-    struct domain *d = page_get_owner(page);
-    unsigned long  pfn = page_to_mfn(page);
-    l3_pgentry_t  *pl3e;
-    unsigned int   i;
-    int            rc = 0, partial = page->partial_pte;
-
-    pl3e = map_domain_page(_mfn(pfn));
-
-    /*
-     * PAE guests allocate full pages, but aren't required to initialize
-     * more than the first four entries; when running in compatibility
-     * mode, however, the full page is visible to the MMU, and hence all
-     * 512 entries must be valid/verified, which is most easily achieved
-     * by clearing them out.
-     */
-    if ( is_pv_32bit_domain(d) )
-        memset(pl3e + 4, 0, (L3_PAGETABLE_ENTRIES - 4) * sizeof(*pl3e));
-
-    for ( i = page->nr_validated_ptes; i < L3_PAGETABLE_ENTRIES;
-          i++, partial = 0 )
-    {
-        if ( is_pv_32bit_domain(d) && (i == 3) )
-        {
-            if ( !(l3e_get_flags(pl3e[i]) & _PAGE_PRESENT) ||
-                 (l3e_get_flags(pl3e[i]) & l3_disallow_mask(d)) )
-                rc = -EINVAL;
-            else
-                rc = get_page_and_type_from_mfn(
-                    _mfn(l3e_get_pfn(pl3e[i])),
-                    PGT_l2_page_table | PGT_pae_xen_l2, d, partial, true);
-        }
-        else if ( !is_guest_l3_slot(i) ||
-                  (rc = get_page_from_l3e(pl3e[i], pfn, d, partial)) > 0 )
-            continue;
-
-        if ( rc == -ERESTART )
-        {
-            page->nr_validated_ptes = i;
-            page->partial_pte = partial ?: 1;
-        }
-        else if ( rc == -EINTR && i )
-        {
-            page->nr_validated_ptes = i;
-            page->partial_pte = 0;
-            rc = -ERESTART;
-        }
-        if ( rc < 0 )
-            break;
-
-        adjust_guest_l3e(pl3e[i], d);
-    }
-
-    if ( rc >= 0 && !pv_create_pae_xen_mappings(d, pl3e) )
-        rc = -EINVAL;
-    if ( rc < 0 && rc != -ERESTART && rc != -EINTR )
-    {
-        gdprintk(XENLOG_WARNING, "Failure in alloc_l3_table: slot %#x\n", i);
-        if ( i )
-        {
-            page->nr_validated_ptes = i;
-            page->partial_pte = 0;
-            current->arch.old_guest_table = page;
-        }
-        while ( i-- > 0 )
-        {
-            if ( !is_guest_l3_slot(i) )
-                continue;
-            unadjust_guest_l3e(pl3e[i], d);
-        }
-    }
-
-    unmap_domain_page(pl3e);
-    return rc > 0 ? 0 : rc;
-}
-
 bool fill_ro_mpt(unsigned long mfn)
 {
     l4_pgentry_t *l4tab = map_domain_page(_mfn(mfn));
@@ -1355,188 +1173,6 @@ void zap_ro_mpt(unsigned long mfn)
     unmap_domain_page(l4tab);
 }
 
-static int alloc_l4_table(struct page_info *page)
-{
-    struct domain *d = page_get_owner(page);
-    unsigned long  pfn = page_to_mfn(page);
-    l4_pgentry_t  *pl4e = map_domain_page(_mfn(pfn));
-    unsigned int   i;
-    int            rc = 0, partial = page->partial_pte;
-
-    for ( i = page->nr_validated_ptes; i < L4_PAGETABLE_ENTRIES;
-          i++, partial = 0 )
-    {
-        if ( !is_guest_l4_slot(d, i) ||
-             (rc = get_page_from_l4e(pl4e[i], pfn, d, partial)) > 0 )
-            continue;
-
-        if ( rc == -ERESTART )
-        {
-            page->nr_validated_ptes = i;
-            page->partial_pte = partial ?: 1;
-        }
-        else if ( rc < 0 )
-        {
-            if ( rc != -EINTR )
-                gdprintk(XENLOG_WARNING,
-                         "Failure in alloc_l4_table: slot %#x\n", i);
-            if ( i )
-            {
-                page->nr_validated_ptes = i;
-                page->partial_pte = 0;
-                if ( rc == -EINTR )
-                    rc = -ERESTART;
-                else
-                {
-                    if ( current->arch.old_guest_table )
-                        page->nr_validated_ptes++;
-                    current->arch.old_guest_table = page;
-                }
-            }
-        }
-        if ( rc < 0 )
-        {
-            unmap_domain_page(pl4e);
-            return rc;
-        }
-
-        adjust_guest_l4e(pl4e[i], d);
-    }
-
-    if ( rc >= 0 )
-    {
-        pv_init_guest_l4_table(pl4e, d, !VM_ASSIST(d, m2p_strict));
-        atomic_inc(&d->arch.pv_domain.nr_l4_pages);
-        rc = 0;
-    }
-    unmap_domain_page(pl4e);
-
-    return rc;
-}
-
-static void free_l1_table(struct page_info *page)
-{
-    struct domain *d = page_get_owner(page);
-    unsigned long pfn = page_to_mfn(page);
-    l1_pgentry_t *pl1e;
-    unsigned int  i;
-
-    pl1e = map_domain_page(_mfn(pfn));
-
-    for ( i = 0; i < L1_PAGETABLE_ENTRIES; i++ )
-        put_page_from_l1e(pl1e[i], d);
-
-    unmap_domain_page(pl1e);
-}
-
-
-static int free_l2_table(struct page_info *page, int preemptible)
-{
-    struct domain *d = page_get_owner(page);
-    unsigned long pfn = page_to_mfn(page);
-    l2_pgentry_t *pl2e;
-    unsigned int  i = page->nr_validated_ptes - 1;
-    int err = 0;
-
-    pl2e = map_domain_page(_mfn(pfn));
-
-    ASSERT(page->nr_validated_ptes);
-    do {
-        if ( is_guest_l2_slot(d, page->u.inuse.type_info, i) &&
-             put_page_from_l2e(pl2e[i], pfn) == 0 &&
-             preemptible && i && hypercall_preempt_check() )
-        {
-           page->nr_validated_ptes = i;
-           err = -ERESTART;
-        }
-    } while ( !err && i-- );
-
-    unmap_domain_page(pl2e);
-
-    if ( !err )
-        page->u.inuse.type_info &= ~PGT_pae_xen_l2;
-
-    return err;
-}
-
-static int free_l3_table(struct page_info *page)
-{
-    struct domain *d = page_get_owner(page);
-    unsigned long pfn = page_to_mfn(page);
-    l3_pgentry_t *pl3e;
-    int rc = 0, partial = page->partial_pte;
-    unsigned int  i = page->nr_validated_ptes - !partial;
-
-    pl3e = map_domain_page(_mfn(pfn));
-
-    do {
-        if ( is_guest_l3_slot(i) )
-        {
-            rc = put_page_from_l3e(pl3e[i], pfn, partial, 0);
-            if ( rc < 0 )
-                break;
-            partial = 0;
-            if ( rc > 0 )
-                continue;
-            unadjust_guest_l3e(pl3e[i], d);
-        }
-    } while ( i-- );
-
-    unmap_domain_page(pl3e);
-
-    if ( rc == -ERESTART )
-    {
-        page->nr_validated_ptes = i;
-        page->partial_pte = partial ?: -1;
-    }
-    else if ( rc == -EINTR && i < L3_PAGETABLE_ENTRIES - 1 )
-    {
-        page->nr_validated_ptes = i + 1;
-        page->partial_pte = 0;
-        rc = -ERESTART;
-    }
-    return rc > 0 ? 0 : rc;
-}
-
-static int free_l4_table(struct page_info *page)
-{
-    struct domain *d = page_get_owner(page);
-    unsigned long pfn = page_to_mfn(page);
-    l4_pgentry_t *pl4e = map_domain_page(_mfn(pfn));
-    int rc = 0, partial = page->partial_pte;
-    unsigned int  i = page->nr_validated_ptes - !partial;
-
-    do {
-        if ( is_guest_l4_slot(d, i) )
-            rc = put_page_from_l4e(pl4e[i], pfn, partial, 0);
-        if ( rc < 0 )
-            break;
-        partial = 0;
-    } while ( i-- );
-
-    if ( rc == -ERESTART )
-    {
-        page->nr_validated_ptes = i;
-        page->partial_pte = partial ?: -1;
-    }
-    else if ( rc == -EINTR && i < L4_PAGETABLE_ENTRIES - 1 )
-    {
-        page->nr_validated_ptes = i + 1;
-        page->partial_pte = 0;
-        rc = -ERESTART;
-    }
-
-    unmap_domain_page(pl4e);
-
-    if ( rc >= 0 )
-    {
-        atomic_dec(&d->arch.pv_domain.nr_l4_pages);
-        rc = 0;
-    }
-
-    return rc;
-}
-
 int page_lock(struct page_info *page)
 {
     unsigned long x, nx;
@@ -1951,134 +1587,6 @@ void get_page_light(struct page_info *page)
     while ( unlikely(y != x) );
 }
 
-static int pv_alloc_page_type(struct page_info *page, unsigned long type,
-                              bool preemptible)
-{
-    struct domain *owner = page_get_owner(page);
-    int rc;
-
-    /* A page table is dirtied when its type count becomes non-zero. */
-    if ( likely(owner != NULL) )
-        paging_mark_dirty(owner, _mfn(page_to_mfn(page)));
-
-    switch ( type & PGT_type_mask )
-    {
-    case PGT_l1_page_table:
-        rc = alloc_l1_table(page);
-        break;
-    case PGT_l2_page_table:
-        rc = alloc_l2_table(page, type, preemptible);
-        break;
-    case PGT_l3_page_table:
-        ASSERT(preemptible);
-        rc = alloc_l3_table(page);
-        break;
-    case PGT_l4_page_table:
-        ASSERT(preemptible);
-        rc = alloc_l4_table(page);
-        break;
-    case PGT_seg_desc_page:
-        rc = alloc_segdesc_page(page);
-        break;
-    default:
-        printk("Bad type in alloc_page_type %lx t=%" PRtype_info " c=%lx\n",
-               type, page->u.inuse.type_info,
-               page->count_info);
-        rc = -EINVAL;
-        BUG();
-    }
-
-    /* No need for atomic update of type_info here: noone else updates it. */
-    smp_wmb();
-    switch ( rc )
-    {
-    case 0:
-        page->u.inuse.type_info |= PGT_validated;
-        break;
-    case -EINTR:
-        ASSERT((page->u.inuse.type_info &
-                (PGT_count_mask|PGT_validated|PGT_partial)) == 1);
-        page->u.inuse.type_info &= ~PGT_count_mask;
-        break;
-    default:
-        ASSERT(rc < 0);
-        gdprintk(XENLOG_WARNING, "Error while validating mfn %" PRI_mfn
-                 " (pfn %" PRI_pfn ") for type %" PRtype_info
-                 ": caf=%08lx taf=%" PRtype_info "\n",
-                 page_to_mfn(page), get_gpfn_from_mfn(page_to_mfn(page)),
-                 type, page->count_info, page->u.inuse.type_info);
-        if ( page != current->arch.old_guest_table )
-            page->u.inuse.type_info = 0;
-        else
-        {
-            ASSERT((page->u.inuse.type_info &
-                    (PGT_count_mask | PGT_validated)) == 1);
-    case -ERESTART:
-            get_page_light(page);
-            page->u.inuse.type_info |= PGT_partial;
-        }
-        break;
-    }
-
-    return rc;
-}
-
-
-int pv_free_page_type(struct page_info *page, unsigned long type,
-                      bool preemptible)
-{
-    struct domain *owner = page_get_owner(page);
-    unsigned long gmfn;
-    int rc;
-
-    if ( likely(owner != NULL) && unlikely(paging_mode_enabled(owner)) )
-    {
-        /* A page table is dirtied when its type count becomes zero. */
-        paging_mark_dirty(owner, _mfn(page_to_mfn(page)));
-
-        ASSERT(!shadow_mode_refcounts(owner));
-
-        gmfn = mfn_to_gmfn(owner, page_to_mfn(page));
-        ASSERT(VALID_M2P(gmfn));
-        /* Page sharing not supported for shadowed domains */
-        if(!SHARED_M2P(gmfn))
-            shadow_remove_all_shadows(owner, _mfn(gmfn));
-    }
-
-    if ( !(type & PGT_partial) )
-    {
-        page->nr_validated_ptes = 1U << PAGETABLE_ORDER;
-        page->partial_pte = 0;
-    }
-
-    switch ( type & PGT_type_mask )
-    {
-    case PGT_l1_page_table:
-        free_l1_table(page);
-        rc = 0;
-        break;
-    case PGT_l2_page_table:
-        rc = free_l2_table(page, preemptible);
-        break;
-    case PGT_l3_page_table:
-        ASSERT(preemptible);
-        rc = free_l3_table(page);
-        break;
-    case PGT_l4_page_table:
-        ASSERT(preemptible);
-        rc = free_l4_table(page);
-        break;
-    default:
-        gdprintk(XENLOG_WARNING, "type %" PRtype_info " mfn %" PRI_mfn "\n",
-                 type, page_to_mfn(page));
-        rc = -EINVAL;
-        BUG();
-    }
-
-    return rc;
-}
-
-
 static int __put_final_page_type(
     struct page_info *page, unsigned long type, int preemptible)
 {
diff --git a/xen/arch/x86/pv/mm.c b/xen/arch/x86/pv/mm.c
index 46e1fcf4e5..f0393b9e3c 100644
--- a/xen/arch/x86/pv/mm.c
+++ b/xen/arch/x86/pv/mm.c
@@ -20,10 +20,13 @@
  * along with this program; If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <xen/event.h>
 #include <xen/guest_access.h>
 
+#include <asm/mm.h>
 #include <asm/pv/mm.h>
 #include <asm/setup.h>
+#include <asm/shadow.h>
 
 /*
  * PTE updates can be done with ordinary writes except:
@@ -251,6 +254,494 @@ bool pv_create_pae_xen_mappings(struct domain *d, 
l3_pgentry_t *pl3e)
     return true;
 }
 
+static int alloc_l1_table(struct page_info *page)
+{
+    struct domain *d = page_get_owner(page);
+    unsigned long  pfn = page_to_mfn(page);
+    l1_pgentry_t  *pl1e;
+    unsigned int   i;
+    int            ret = 0;
+
+    pl1e = map_domain_page(_mfn(pfn));
+
+    for ( i = 0; i < L1_PAGETABLE_ENTRIES; i++ )
+    {
+        switch ( ret = get_page_from_l1e(pl1e[i], d, d) )
+        {
+        default:
+            goto fail;
+        case 0:
+            break;
+        case _PAGE_RW ... _PAGE_RW | PAGE_CACHE_ATTRS:
+            ASSERT(!(ret & ~(_PAGE_RW | PAGE_CACHE_ATTRS)));
+            l1e_flip_flags(pl1e[i], ret);
+            break;
+        }
+
+        adjust_guest_l1e(pl1e[i], d);
+    }
+
+    unmap_domain_page(pl1e);
+    return 0;
+
+ fail:
+    gdprintk(XENLOG_WARNING, "Failure in alloc_l1_table: slot %#x\n", i);
+    while ( i-- > 0 )
+        put_page_from_l1e(pl1e[i], d);
+
+    unmap_domain_page(pl1e);
+    return ret;
+}
+
+static int alloc_l2_table(struct page_info *page, unsigned long type,
+                          bool preemptible)
+{
+    struct domain *d = page_get_owner(page);
+    unsigned long  pfn = page_to_mfn(page);
+    l2_pgentry_t  *pl2e;
+    unsigned int   i;
+    int            rc = 0;
+
+    pl2e = map_domain_page(_mfn(pfn));
+
+    for ( i = page->nr_validated_ptes; i < L2_PAGETABLE_ENTRIES; i++ )
+    {
+        if ( preemptible && i > page->nr_validated_ptes
+             && hypercall_preempt_check() )
+        {
+            page->nr_validated_ptes = i;
+            rc = -ERESTART;
+            break;
+        }
+
+        if ( !is_guest_l2_slot(d, type, i) ||
+             (rc = get_page_from_l2e(pl2e[i], pfn, d)) > 0 )
+            continue;
+
+        if ( rc < 0 )
+        {
+            gdprintk(XENLOG_WARNING, "Failure in alloc_l2_table: slot %#x\n", 
i);
+            while ( i-- > 0 )
+                if ( is_guest_l2_slot(d, type, i) )
+                    put_page_from_l2e(pl2e[i], pfn);
+            break;
+        }
+
+        adjust_guest_l2e(pl2e[i], d);
+    }
+
+    if ( rc >= 0 && (type & PGT_pae_xen_l2) )
+    {
+        /* Xen private mappings. */
+        memcpy(&pl2e[COMPAT_L2_PAGETABLE_FIRST_XEN_SLOT(d)],
+               &compat_idle_pg_table_l2[
+                   l2_table_offset(HIRO_COMPAT_MPT_VIRT_START)],
+               COMPAT_L2_PAGETABLE_XEN_SLOTS(d) * sizeof(*pl2e));
+    }
+
+    unmap_domain_page(pl2e);
+    return rc > 0 ? 0 : rc;
+}
+
+static int alloc_l3_table(struct page_info *page)
+{
+    struct domain *d = page_get_owner(page);
+    unsigned long  pfn = page_to_mfn(page);
+    l3_pgentry_t  *pl3e;
+    unsigned int   i;
+    int            rc = 0, partial = page->partial_pte;
+
+    pl3e = map_domain_page(_mfn(pfn));
+
+    /*
+     * PAE guests allocate full pages, but aren't required to initialize
+     * more than the first four entries; when running in compatibility
+     * mode, however, the full page is visible to the MMU, and hence all
+     * 512 entries must be valid/verified, which is most easily achieved
+     * by clearing them out.
+     */
+    if ( is_pv_32bit_domain(d) )
+        memset(pl3e + 4, 0, (L3_PAGETABLE_ENTRIES - 4) * sizeof(*pl3e));
+
+    for ( i = page->nr_validated_ptes; i < L3_PAGETABLE_ENTRIES;
+          i++, partial = 0 )
+    {
+        if ( is_pv_32bit_domain(d) && (i == 3) )
+        {
+            if ( !(l3e_get_flags(pl3e[i]) & _PAGE_PRESENT) ||
+                 (l3e_get_flags(pl3e[i]) & l3_disallow_mask(d)) )
+                rc = -EINVAL;
+            else
+                rc = get_page_and_type_from_mfn(
+                    _mfn(l3e_get_pfn(pl3e[i])),
+                    PGT_l2_page_table | PGT_pae_xen_l2, d, partial, true);
+        }
+        else if ( !is_guest_l3_slot(i) ||
+                  (rc = get_page_from_l3e(pl3e[i], pfn, d, partial)) > 0 )
+            continue;
+
+        if ( rc == -ERESTART )
+        {
+            page->nr_validated_ptes = i;
+            page->partial_pte = partial ?: 1;
+        }
+        else if ( rc == -EINTR && i )
+        {
+            page->nr_validated_ptes = i;
+            page->partial_pte = 0;
+            rc = -ERESTART;
+        }
+        if ( rc < 0 )
+            break;
+
+        adjust_guest_l3e(pl3e[i], d);
+    }
+
+    if ( rc >= 0 && !pv_create_pae_xen_mappings(d, pl3e) )
+        rc = -EINVAL;
+    if ( rc < 0 && rc != -ERESTART && rc != -EINTR )
+    {
+        gdprintk(XENLOG_WARNING, "Failure in alloc_l3_table: slot %#x\n", i);
+        if ( i )
+        {
+            page->nr_validated_ptes = i;
+            page->partial_pte = 0;
+            current->arch.old_guest_table = page;
+        }
+        while ( i-- > 0 )
+        {
+            if ( !is_guest_l3_slot(i) )
+                continue;
+            unadjust_guest_l3e(pl3e[i], d);
+        }
+    }
+
+    unmap_domain_page(pl3e);
+    return rc > 0 ? 0 : rc;
+}
+
+static int alloc_l4_table(struct page_info *page)
+{
+    struct domain *d = page_get_owner(page);
+    unsigned long  pfn = page_to_mfn(page);
+    l4_pgentry_t  *pl4e = map_domain_page(_mfn(pfn));
+    unsigned int   i;
+    int            rc = 0, partial = page->partial_pte;
+
+    for ( i = page->nr_validated_ptes; i < L4_PAGETABLE_ENTRIES;
+          i++, partial = 0 )
+    {
+        if ( !is_guest_l4_slot(d, i) ||
+             (rc = get_page_from_l4e(pl4e[i], pfn, d, partial)) > 0 )
+            continue;
+
+        if ( rc == -ERESTART )
+        {
+            page->nr_validated_ptes = i;
+            page->partial_pte = partial ?: 1;
+        }
+        else if ( rc < 0 )
+        {
+            if ( rc != -EINTR )
+                gdprintk(XENLOG_WARNING,
+                         "Failure in alloc_l4_table: slot %#x\n", i);
+            if ( i )
+            {
+                page->nr_validated_ptes = i;
+                page->partial_pte = 0;
+                if ( rc == -EINTR )
+                    rc = -ERESTART;
+                else
+                {
+                    if ( current->arch.old_guest_table )
+                        page->nr_validated_ptes++;
+                    current->arch.old_guest_table = page;
+                }
+            }
+        }
+        if ( rc < 0 )
+        {
+            unmap_domain_page(pl4e);
+            return rc;
+        }
+
+        adjust_guest_l4e(pl4e[i], d);
+    }
+
+    if ( rc >= 0 )
+    {
+        pv_init_guest_l4_table(pl4e, d, !VM_ASSIST(d, m2p_strict));
+        atomic_inc(&d->arch.pv_domain.nr_l4_pages);
+        rc = 0;
+    }
+    unmap_domain_page(pl4e);
+
+    return rc;
+}
+
+static void free_l1_table(struct page_info *page)
+{
+    struct domain *d = page_get_owner(page);
+    unsigned long pfn = page_to_mfn(page);
+    l1_pgentry_t *pl1e;
+    unsigned int  i;
+
+    pl1e = map_domain_page(_mfn(pfn));
+
+    for ( i = 0; i < L1_PAGETABLE_ENTRIES; i++ )
+        put_page_from_l1e(pl1e[i], d);
+
+    unmap_domain_page(pl1e);
+}
+
+static int free_l2_table(struct page_info *page, int preemptible)
+{
+    struct domain *d = page_get_owner(page);
+    unsigned long pfn = page_to_mfn(page);
+    l2_pgentry_t *pl2e;
+    unsigned int  i = page->nr_validated_ptes - 1;
+    int err = 0;
+
+    pl2e = map_domain_page(_mfn(pfn));
+
+    ASSERT(page->nr_validated_ptes);
+    do {
+        if ( is_guest_l2_slot(d, page->u.inuse.type_info, i) &&
+             put_page_from_l2e(pl2e[i], pfn) == 0 &&
+             preemptible && i && hypercall_preempt_check() )
+        {
+           page->nr_validated_ptes = i;
+           err = -ERESTART;
+        }
+    } while ( !err && i-- );
+
+    unmap_domain_page(pl2e);
+
+    if ( !err )
+        page->u.inuse.type_info &= ~PGT_pae_xen_l2;
+
+    return err;
+}
+
+static int free_l3_table(struct page_info *page)
+{
+    struct domain *d = page_get_owner(page);
+    unsigned long pfn = page_to_mfn(page);
+    l3_pgentry_t *pl3e;
+    int rc = 0, partial = page->partial_pte;
+    unsigned int  i = page->nr_validated_ptes - !partial;
+
+    pl3e = map_domain_page(_mfn(pfn));
+
+    do {
+        if ( is_guest_l3_slot(i) )
+        {
+            rc = put_page_from_l3e(pl3e[i], pfn, partial, 0);
+            if ( rc < 0 )
+                break;
+            partial = 0;
+            if ( rc > 0 )
+                continue;
+            unadjust_guest_l3e(pl3e[i], d);
+        }
+    } while ( i-- );
+
+    unmap_domain_page(pl3e);
+
+    if ( rc == -ERESTART )
+    {
+        page->nr_validated_ptes = i;
+        page->partial_pte = partial ?: -1;
+    }
+    else if ( rc == -EINTR && i < L3_PAGETABLE_ENTRIES - 1 )
+    {
+        page->nr_validated_ptes = i + 1;
+        page->partial_pte = 0;
+        rc = -ERESTART;
+    }
+    return rc > 0 ? 0 : rc;
+}
+
+static int free_l4_table(struct page_info *page)
+{
+    struct domain *d = page_get_owner(page);
+    unsigned long pfn = page_to_mfn(page);
+    l4_pgentry_t *pl4e = map_domain_page(_mfn(pfn));
+    int rc = 0, partial = page->partial_pte;
+    unsigned int  i = page->nr_validated_ptes - !partial;
+
+    do {
+        if ( is_guest_l4_slot(d, i) )
+            rc = put_page_from_l4e(pl4e[i], pfn, partial, 0);
+        if ( rc < 0 )
+            break;
+        partial = 0;
+    } while ( i-- );
+
+    if ( rc == -ERESTART )
+    {
+        page->nr_validated_ptes = i;
+        page->partial_pte = partial ?: -1;
+    }
+    else if ( rc == -EINTR && i < L4_PAGETABLE_ENTRIES - 1 )
+    {
+        page->nr_validated_ptes = i + 1;
+        page->partial_pte = 0;
+        rc = -ERESTART;
+    }
+
+    unmap_domain_page(pl4e);
+
+    if ( rc >= 0 )
+    {
+        atomic_dec(&d->arch.pv_domain.nr_l4_pages);
+        rc = 0;
+    }
+
+    return rc;
+}
+
+static int alloc_segdesc_page(struct page_info *page)
+{
+    const struct domain *owner = page_get_owner(page);
+    struct desc_struct *descs = __map_domain_page(page);
+    unsigned i;
+
+    for ( i = 0; i < 512; i++ )
+        if ( unlikely(!check_descriptor(owner, &descs[i])) )
+            break;
+
+    unmap_domain_page(descs);
+
+    return i == 512 ? 0 : -EINVAL;
+}
+
+int pv_alloc_page_type(struct page_info *page, unsigned long type,
+                       bool preemptible)
+{
+    struct domain *owner = page_get_owner(page);
+    int rc;
+
+    /* A page table is dirtied when its type count becomes non-zero. */
+    if ( likely(owner != NULL) )
+        paging_mark_dirty(owner, _mfn(page_to_mfn(page)));
+
+    switch ( type & PGT_type_mask )
+    {
+    case PGT_l1_page_table:
+        rc = alloc_l1_table(page);
+        break;
+    case PGT_l2_page_table:
+        rc = alloc_l2_table(page, type, preemptible);
+        break;
+    case PGT_l3_page_table:
+        ASSERT(preemptible);
+        rc = alloc_l3_table(page);
+        break;
+    case PGT_l4_page_table:
+        ASSERT(preemptible);
+        rc = alloc_l4_table(page);
+        break;
+    case PGT_seg_desc_page:
+        rc = alloc_segdesc_page(page);
+        break;
+    default:
+        printk("Bad type in alloc_page_type %lx t=%" PRtype_info " c=%lx\n",
+               type, page->u.inuse.type_info,
+               page->count_info);
+        rc = -EINVAL;
+        BUG();
+    }
+
+    /* No need for atomic update of type_info here: noone else updates it. */
+    smp_wmb();
+    switch ( rc )
+    {
+    case 0:
+        page->u.inuse.type_info |= PGT_validated;
+        break;
+    case -EINTR:
+        ASSERT((page->u.inuse.type_info &
+                (PGT_count_mask|PGT_validated|PGT_partial)) == 1);
+        page->u.inuse.type_info &= ~PGT_count_mask;
+        break;
+    default:
+        ASSERT(rc < 0);
+        gdprintk(XENLOG_WARNING, "Error while validating mfn %" PRI_mfn
+                 " (pfn %" PRI_pfn ") for type %" PRtype_info
+                 ": caf=%08lx taf=%" PRtype_info "\n",
+                 page_to_mfn(page), get_gpfn_from_mfn(page_to_mfn(page)),
+                 type, page->count_info, page->u.inuse.type_info);
+        if ( page != current->arch.old_guest_table )
+            page->u.inuse.type_info = 0;
+        else
+        {
+            ASSERT((page->u.inuse.type_info &
+                    (PGT_count_mask | PGT_validated)) == 1);
+    case -ERESTART:
+            get_page_light(page);
+            page->u.inuse.type_info |= PGT_partial;
+        }
+        break;
+    }
+
+    return rc;
+}
+
+int pv_free_page_type(struct page_info *page, unsigned long type,
+                      bool preemptible)
+{
+    struct domain *owner = page_get_owner(page);
+    unsigned long gmfn;
+    int rc;
+
+    if ( likely(owner != NULL) && unlikely(paging_mode_enabled(owner)) )
+    {
+        /* A page table is dirtied when its type count becomes zero. */
+        paging_mark_dirty(owner, _mfn(page_to_mfn(page)));
+
+        ASSERT(!shadow_mode_refcounts(owner));
+
+        gmfn = mfn_to_gmfn(owner, page_to_mfn(page));
+        ASSERT(VALID_M2P(gmfn));
+        /* Page sharing not supported for shadowed domains */
+        if(!SHARED_M2P(gmfn))
+            shadow_remove_all_shadows(owner, _mfn(gmfn));
+    }
+
+    if ( !(type & PGT_partial) )
+    {
+        page->nr_validated_ptes = 1U << PAGETABLE_ORDER;
+        page->partial_pte = 0;
+    }
+
+    switch ( type & PGT_type_mask )
+    {
+    case PGT_l1_page_table:
+        free_l1_table(page);
+        rc = 0;
+        break;
+    case PGT_l2_page_table:
+        rc = free_l2_table(page, preemptible);
+        break;
+    case PGT_l3_page_table:
+        ASSERT(preemptible);
+        rc = free_l3_table(page);
+        break;
+    case PGT_l4_page_table:
+        ASSERT(preemptible);
+        rc = free_l4_table(page);
+        break;
+    default:
+        gdprintk(XENLOG_WARNING, "type %" PRtype_info " mfn %" PRI_mfn "\n",
+                 type, page_to_mfn(page));
+        rc = -EINVAL;
+        BUG();
+    }
+
+    return rc;
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/xen/include/asm-x86/mm.h b/xen/include/asm-x86/mm.h
index 6857651db1..7480341240 100644
--- a/xen/include/asm-x86/mm.h
+++ b/xen/include/asm-x86/mm.h
@@ -302,9 +302,6 @@ static inline void *__page_to_virt(const struct page_info 
*pg)
                     (PAGE_SIZE / (sizeof(*pg) & -sizeof(*pg))));
 }
 
-int pv_free_page_type(struct page_info *page, unsigned long type,
-                      bool preemptible);
-
 bool_t fill_ro_mpt(unsigned long mfn);
 void zap_ro_mpt(unsigned long mfn);
 
diff --git a/xen/include/asm-x86/pv/mm.h b/xen/include/asm-x86/pv/mm.h
index 648b26d7d0..7de5ea2f12 100644
--- a/xen/include/asm-x86/pv/mm.h
+++ b/xen/include/asm-x86/pv/mm.h
@@ -95,10 +95,17 @@ void pv_arch_init_memory(void);
 
 int pv_new_guest_cr3(unsigned long pfn);
 
+int pv_alloc_page_type(struct page_info *page, unsigned long type,
+                       bool preemptible);
+int pv_free_page_type(struct page_info *page, unsigned long type,
+                      bool preemptible);
+
 #else
 
 #include <xen/errno.h>
 
+#include <asm/bug.h>
+
 static inline void pv_get_guest_eff_l1e(unsigned long addr,
                                         l1_pgentry_t *eff_l1e)
 {}
@@ -125,6 +132,13 @@ static inline void pv_arch_init_memory(void) {}
 
 static inline int pv_new_guest_cr3(unsigned long pfn) { return -EINVAL; }
 
+static inline int pv_alloc_page_type(struct page_info *page, unsigned long 
type,
+                                     bool preemptible)
+{ BUG(); return -EINVAL; }
+static inline int pv_free_page_type(struct page_info *page, unsigned long type,
+                                    bool preemptible)
+{ BUG(); return -EINVAL; }
+
 #endif
 
 #endif /* __X86_PV_MM_H__ */
-- 
2.11.0


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