From: Hongyan Xia <hongyxia@amazon.com>
Building a PV dom0 is allocating from the domheap but uses it like the
xenheap. Use the pages as they should be.
Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
Signed-off-by: Julien Grall <jgrall@amazon.com>
Signed-off-by: Elias El Yandouzi <eliasely@amazon.com>
----
Changes in V4:
* Reduce the scope of l{1,2,4}start_mfn variables
* Make the macro `UNMAP_MAP_AND_ADVANCE` return the new virtual address
Changes in V3:
* Fold following patch 'x86/pv: Map L4 page table for shim domain'
Changes in V2:
* Clarify the commit message
* Break the patch in two parts
Changes since Hongyan's version:
* Rebase
* Remove spurious newline
diff --git a/xen/arch/x86/pv/dom0_build.c b/xen/arch/x86/pv/dom0_build.c
index 18b7a3e4e025..b03df609cadb 100644
--- a/xen/arch/x86/pv/dom0_build.c
+++ b/xen/arch/x86/pv/dom0_build.c
@@ -382,6 +382,7 @@ static int __init dom0_construct(struct domain *d,
l3_pgentry_t *l3tab = NULL, *l3start = NULL;
l2_pgentry_t *l2tab = NULL, *l2start = NULL;
l1_pgentry_t *l1tab = NULL, *l1start = NULL;
+ mfn_t l3start_mfn = INVALID_MFN;
/*
* This fully describes the memory layout of the initial domain. All
@@ -719,22 +720,34 @@ static int __init dom0_construct(struct domain *d,
v->arch.pv.event_callback_cs = FLAT_COMPAT_KERNEL_CS;
}
+#define UNMAP_MAP_AND_ADVANCE(mfn_var, virt_var, maddr) ({ \
+ do { \
+ unmap_domain_page(virt_var); \
+ mfn_var = maddr_to_mfn(maddr); \
+ maddr += PAGE_SIZE; \
+ virt_var = map_domain_page(mfn_var); \
+ } while ( false ); \
+ virt_var; \
+})
+
if ( !compat )
{
+ mfn_t l4start_mfn;
maddr_to_page(mpt_alloc)->u.inuse.type_info = PGT_l4_page_table;
- l4start = l4tab = __va(mpt_alloc); mpt_alloc += PAGE_SIZE;
+ l4tab = UNMAP_MAP_AND_ADVANCE(l4start_mfn, l4start, mpt_alloc);
clear_page(l4tab);
- init_xen_l4_slots(l4tab, _mfn(virt_to_mfn(l4start)),
- d, INVALID_MFN, true);
- v->arch.guest_table = pagetable_from_paddr(__pa(l4start));
+ init_xen_l4_slots(l4tab, l4start_mfn, d, INVALID_MFN, true);
+ v->arch.guest_table = pagetable_from_mfn(l4start_mfn);
}
else
{
/* Monitor table already created by switch_compat(). */
- l4start = l4tab = __va(pagetable_get_paddr(v->arch.guest_table));
+ mfn_t l4start_mfn = pagetable_get_mfn(v->arch.guest_table);
+ l4start = l4tab = map_domain_page(l4start_mfn);
/* See public/xen.h on why the following is needed. */
maddr_to_page(mpt_alloc)->u.inuse.type_info = PGT_l3_page_table;
l3start = __va(mpt_alloc); mpt_alloc += PAGE_SIZE;
+ UNMAP_MAP_AND_ADVANCE(l3start_mfn, l3start, mpt_alloc);
}
l4tab += l4_table_offset(v_start);
@@ -743,15 +756,17 @@ static int __init dom0_construct(struct domain *d,
{
if ( !((unsigned long)l1tab & (PAGE_SIZE-1)) )
{
+ mfn_t l1start_mfn;
maddr_to_page(mpt_alloc)->u.inuse.type_info = PGT_l1_page_table;
- l1start = l1tab = __va(mpt_alloc); mpt_alloc += PAGE_SIZE;
+ l1tab = UNMAP_MAP_AND_ADVANCE(l1start_mfn, l1start, mpt_alloc);
clear_page(l1tab);
if ( count == 0 )
l1tab += l1_table_offset(v_start);
if ( !((unsigned long)l2tab & (PAGE_SIZE-1)) )
{
+ mfn_t l2start_mfn;
maddr_to_page(mpt_alloc)->u.inuse.type_info = PGT_l2_page_table;
- l2start = l2tab = __va(mpt_alloc); mpt_alloc += PAGE_SIZE;
+ l2tab = UNMAP_MAP_AND_ADVANCE(l2start_mfn, l2start, mpt_alloc);
clear_page(l2tab);
if ( count == 0 )
l2tab += l2_table_offset(v_start);
@@ -761,19 +776,19 @@ static int __init dom0_construct(struct domain *d,
{
maddr_to_page(mpt_alloc)->u.inuse.type_info =
PGT_l3_page_table;
- l3start = __va(mpt_alloc); mpt_alloc += PAGE_SIZE;
+ UNMAP_MAP_AND_ADVANCE(l3start_mfn, l3start, mpt_alloc);
}
l3tab = l3start;
clear_page(l3tab);
if ( count == 0 )
l3tab += l3_table_offset(v_start);
- *l4tab = l4e_from_paddr(__pa(l3start), L4_PROT);
+ *l4tab = l4e_from_mfn(l3start_mfn, L4_PROT);
l4tab++;
}
- *l3tab = l3e_from_paddr(__pa(l2start), L3_PROT);
+ *l3tab = l3e_from_mfn(l2start_mfn, L3_PROT);
l3tab++;
}
- *l2tab = l2e_from_paddr(__pa(l1start), L2_PROT);
+ *l2tab = l2e_from_mfn(l1start_mfn, L2_PROT);
l2tab++;
}
if ( count < initrd_pfn || count >= initrd_pfn + PFN_UP(initrd_len) )
@@ -792,27 +807,32 @@ static int __init dom0_construct(struct domain *d,
if ( compat )
{
- l2_pgentry_t *l2t;
-
/* Ensure the first four L3 entries are all populated. */
for ( i = 0, l3tab = l3start; i < 4; ++i, ++l3tab )
{
if ( !l3e_get_intpte(*l3tab) )
{
+ mfn_t l2start_mfn;
maddr_to_page(mpt_alloc)->u.inuse.type_info = PGT_l2_page_table;
- l2tab = __va(mpt_alloc); mpt_alloc += PAGE_SIZE;
- clear_page(l2tab);
- *l3tab = l3e_from_paddr(__pa(l2tab), L3_PROT);
+ UNMAP_MAP_AND_ADVANCE(l2start_mfn, l2start, mpt_alloc);
+ clear_page(l2start);
+ *l3tab = l3e_from_mfn(l2start_mfn, L3_PROT);
}
if ( i == 3 )
l3e_get_page(*l3tab)->u.inuse.type_info |= PGT_pae_xen_l2;
}
- l2t = map_l2t_from_l3e(l3start[3]);
- init_xen_pae_l2_slots(l2t, d);
- unmap_domain_page(l2t);
+ UNMAP_DOMAIN_PAGE(l2start);
+ l2start = map_l2t_from_l3e(l3start[3]);
+ init_xen_pae_l2_slots(l2start, d);
}
+#undef UNMAP_MAP_AND_ADVANCE
+
+ UNMAP_DOMAIN_PAGE(l1start);
+ UNMAP_DOMAIN_PAGE(l2start);
+ UNMAP_DOMAIN_PAGE(l3start);
+
/* Pages that are part of page tables must be read only. */
mark_pv_pt_pages_rdonly(d, l4start, vpt_start, nr_pt_pages, &flush_flags);
@@ -987,6 +1007,8 @@ static int __init dom0_construct(struct domain *d,
pv_shim_setup_dom(d, l4start, v_start, vxenstore_start, vconsole_start,
vphysmap_start, si);
+ UNMAP_DOMAIN_PAGE(l4start);
+
#ifdef CONFIG_COMPAT
if ( compat )
xlat_start_info(si, pv_shim ? XLAT_start_info_console_domU
--
2.40.1