Utilize as many of the bits available in the union as possible, without
(just to be on the safe side) colliding with any of the bits outside of
PGT_type_mask.
Note that the first and last hunks of the xen/include/asm-x86/mm.h
change are merely code motion.
Signed-off-by: Jan Beulich <jbeul...@suse.com>
Acked-by: Tim Deegan <t...@xen.org>
---
v2: Slightly extend description.
--- a/xen/arch/x86/mm/shadow/private.h
+++ b/xen/arch/x86/mm/shadow/private.h
@@ -520,7 +520,7 @@ void sh_destroy_shadow(struct domain *d,
* Returns 0 for failure, 1 for success. */
static inline int sh_get_ref(struct domain *d, mfn_t smfn, paddr_t entry_pa)
{
- u32 x, nx;
+ unsigned long x, nx;
struct page_info *sp = mfn_to_page(smfn);
ASSERT(mfn_valid(smfn));
@@ -529,7 +529,7 @@ static inline int sh_get_ref(struct doma
x = sp->u.sh.count;
nx = x + 1;
- if ( unlikely(nx >= (1U << PAGE_SH_REFCOUNT_WIDTH)) )
+ if ( unlikely(nx >= (1UL << PAGE_SH_REFCOUNT_WIDTH)) )
{
SHADOW_PRINTK("shadow ref overflow, gmfn=%lx smfn=%lx\n",
__backpointer(sp), mfn_x(smfn));
@@ -553,7 +553,7 @@ static inline int sh_get_ref(struct doma
* physical address of the shadow entry that held this reference. */
static inline void sh_put_ref(struct domain *d, mfn_t smfn, paddr_t entry_pa)
{
- u32 x, nx;
+ unsigned long x, nx;
struct page_info *sp = mfn_to_page(smfn);
ASSERT(mfn_valid(smfn));
@@ -571,8 +571,8 @@ static inline void sh_put_ref(struct dom
if ( unlikely(x == 0) )
{
- SHADOW_ERROR("shadow ref underflow, smfn=%lx oc=%08x t=%#x\n",
- mfn_x(smfn), sp->u.sh.count, sp->u.sh.type);
+ SHADOW_ERROR("shadow ref underflow, smfn=%lx oc=%#lx t=%#x\n",
+ mfn_x(smfn), sp->u.sh.count + 0UL, sp->u.sh.type);
BUG();
}
--- a/xen/include/asm-x86/mm.h
+++ b/xen/include/asm-x86/mm.h
@@ -18,6 +18,77 @@
*/
#define PFN_ORDER(_pfn) ((_pfn)->v.free.order)
+#define PG_shift(idx) (BITS_PER_LONG - (idx))
+#define PG_mask(x, idx) (x ## UL << PG_shift(idx))
+
+ /* The following page types are MUTUALLY EXCLUSIVE. */
+#define PGT_none PG_mask(0, 3) /* no special uses of this page */
+#define PGT_l1_page_table PG_mask(1, 3) /* using as an L1 page table? */
+#define PGT_l2_page_table PG_mask(2, 3) /* using as an L2 page table? */
+#define PGT_l3_page_table PG_mask(3, 3) /* using as an L3 page table? */
+#define PGT_l4_page_table PG_mask(4, 3) /* using as an L4 page table? */
+#define PGT_seg_desc_page PG_mask(5, 3) /* using this page in a GDT/LDT? */
+#define PGT_shared_page PG_mask(6, 3) /* CoW sharable page */
+#define PGT_writable_page PG_mask(7, 3) /* has writable mappings? */
+#define PGT_type_mask PG_mask(7, 3) /* Bits 61-63. */
+
+ /* Page is locked? */
+#define _PGT_locked PG_shift(4)
+#define PGT_locked PG_mask(1, 4)
+ /* Owning guest has pinned this page to its current type? */
+#define _PGT_pinned PG_shift(5)
+#define PGT_pinned PG_mask(1, 5)
+ /* Has this page been validated for use as its current type? */
+#define _PGT_validated PG_shift(6)
+#define PGT_validated PG_mask(1, 6)
+ /* PAE only: is this an L2 page directory containing Xen-private mappings? */
+#define _PGT_pae_xen_l2 PG_shift(7)
+#define PGT_pae_xen_l2 PG_mask(1, 7)
+/* Has this page been *partially* validated for use as its current type? */
+#define _PGT_partial PG_shift(8)
+#define PGT_partial PG_mask(1, 8)
+
+ /* Count of uses of this frame as its current type. */
+#define PGT_count_width PG_shift(8)
+#define PGT_count_mask ((1UL<<PGT_count_width)-1)
+
+/* Are the 'type mask' bits identical? */
+#define PGT_type_equal(x, y) (!(((x) ^ (y)) & PGT_type_mask))
+
+ /* Cleared when the owning guest 'frees' this page. */
+#define _PGC_allocated PG_shift(1)
+#define PGC_allocated PG_mask(1, 1)
+ /* Page is Xen heap? */
+#define _PGC_xen_heap PG_shift(2)
+#define PGC_xen_heap PG_mask(1, 2)
+ /* Set when is using a page as a page table */
+#define _PGC_page_table PG_shift(3)
+#define PGC_page_table PG_mask(1, 3)
+ /* 3-bit PAT/PCD/PWT cache-attribute hint. */
+#define PGC_cacheattr_base PG_shift(6)
+#define PGC_cacheattr_mask PG_mask(7, 6)
+ /* Page is broken? */
+#define _PGC_broken PG_shift(7)
+#define PGC_broken PG_mask(1, 7)
+ /* Mutually-exclusive page states: { inuse, offlining, offlined, free }. */
+#define PGC_state PG_mask(3, 9)
+#define PGC_state_inuse PG_mask(0, 9)
+#define PGC_state_offlining PG_mask(1, 9)
+#define PGC_state_offlined PG_mask(2, 9)
+#define PGC_state_free PG_mask(3, 9)
+#define page_state_is(pg, st) (((pg)->count_info&PGC_state) == PGC_state_##st)
+
+ /* Count of references to this frame. */
+#define PGC_count_width PG_shift(9)
+#define PGC_count_mask ((1UL<<PGC_count_width)-1)
+
+/*
+ * Page needs to be scrubbed. Since this bit can only be set on a page that is
+ * free (i.e. in PGC_state_free) we can reuse PGC_allocated bit.
+ */
+#define _PGC_need_scrub _PGC_allocated
+#define PGC_need_scrub PGC_allocated
+
#ifndef CONFIG_BIGMEM
/*
* This definition is solely for the use in struct page_info (and
@@ -82,7 +153,7 @@ struct page_info
unsigned long type:5; /* What kind of shadow is this? */
unsigned long pinned:1; /* Is the shadow pinned? */
unsigned long head:1; /* Is this the first page of the shadow? */
-#define PAGE_SH_REFCOUNT_WIDTH 25
+#define PAGE_SH_REFCOUNT_WIDTH (PGT_count_width - 7)
unsigned long count:PAGE_SH_REFCOUNT_WIDTH; /* Reference count */
} sh;
@@ -198,77 +269,6 @@ struct page_info
#undef __pdx_t
-#define PG_shift(idx) (BITS_PER_LONG - (idx))
-#define PG_mask(x, idx) (x ## UL << PG_shift(idx))
-
- /* The following page types are MUTUALLY EXCLUSIVE. */
-#define PGT_none PG_mask(0, 3) /* no special uses of this page */
-#define PGT_l1_page_table PG_mask(1, 3) /* using as an L1 page table? */
-#define PGT_l2_page_table PG_mask(2, 3) /* using as an L2 page table? */
-#define PGT_l3_page_table PG_mask(3, 3) /* using as an L3 page table? */
-#define PGT_l4_page_table PG_mask(4, 3) /* using as an L4 page table? */
-#define PGT_seg_desc_page PG_mask(5, 3) /* using this page in a GDT/LDT? */
-#define PGT_shared_page PG_mask(6, 3) /* CoW sharable page */
-#define PGT_writable_page PG_mask(7, 3) /* has writable mappings? */
-#define PGT_type_mask PG_mask(7, 3) /* Bits 61-63. */
-
- /* Page is locked? */
-#define _PGT_locked PG_shift(4)
-#define PGT_locked PG_mask(1, 4)
- /* Owning guest has pinned this page to its current type? */
-#define _PGT_pinned PG_shift(5)
-#define PGT_pinned PG_mask(1, 5)
- /* Has this page been validated for use as its current type? */
-#define _PGT_validated PG_shift(6)
-#define PGT_validated PG_mask(1, 6)
- /* PAE only: is this an L2 page directory containing Xen-private mappings? */
-#define _PGT_pae_xen_l2 PG_shift(7)
-#define PGT_pae_xen_l2 PG_mask(1, 7)
-/* Has this page been *partially* validated for use as its current type? */
-#define _PGT_partial PG_shift(8)
-#define PGT_partial PG_mask(1, 8)
-
- /* Count of uses of this frame as its current type. */
-#define PGT_count_width PG_shift(8)
-#define PGT_count_mask ((1UL<<PGT_count_width)-1)
-
-/* Are the 'type mask' bits identical? */
-#define PGT_type_equal(x, y) (!(((x) ^ (y)) & PGT_type_mask))
-
- /* Cleared when the owning guest 'frees' this page. */
-#define _PGC_allocated PG_shift(1)
-#define PGC_allocated PG_mask(1, 1)
- /* Page is Xen heap? */
-#define _PGC_xen_heap PG_shift(2)
-#define PGC_xen_heap PG_mask(1, 2)
- /* Set when is using a page as a page table */
-#define _PGC_page_table PG_shift(3)
-#define PGC_page_table PG_mask(1, 3)
- /* 3-bit PAT/PCD/PWT cache-attribute hint. */
-#define PGC_cacheattr_base PG_shift(6)
-#define PGC_cacheattr_mask PG_mask(7, 6)
- /* Page is broken? */
-#define _PGC_broken PG_shift(7)
-#define PGC_broken PG_mask(1, 7)
- /* Mutually-exclusive page states: { inuse, offlining, offlined, free }. */
-#define PGC_state PG_mask(3, 9)
-#define PGC_state_inuse PG_mask(0, 9)
-#define PGC_state_offlining PG_mask(1, 9)
-#define PGC_state_offlined PG_mask(2, 9)
-#define PGC_state_free PG_mask(3, 9)
-#define page_state_is(pg, st) (((pg)->count_info&PGC_state) == PGC_state_##st)
-
- /* Count of references to this frame. */
-#define PGC_count_width PG_shift(9)
-#define PGC_count_mask ((1UL<<PGC_count_width)-1)
-
-/*
- * Page needs to be scrubbed. Since this bit can only be set on a page that is
- * free (i.e. in PGC_state_free) we can reuse PGC_allocated bit.
- */
-#define _PGC_need_scrub _PGC_allocated
-#define PGC_need_scrub PGC_allocated
-
#define is_xen_heap_page(page) ((page)->count_info & PGC_xen_heap)
#define is_xen_heap_mfn(mfn) \
(__mfn_valid(mfn) && is_xen_heap_page(__mfn_to_page(mfn)))
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