@@ -160,6 +160,7 @@
#endif
#define PGC_no_buddy_merge PGC_static
+#define PGC_preserved (PGC_extra | PGC_static | PGC_broken)
#ifndef PGT_TYPE_INFO_INITIALIZER
#define PGT_TYPE_INFO_INITIALIZER 0
@@ -1427,12 +1428,11 @@ static bool mark_page_free(struct page_info *pg, mfn_t mfn)
{
case PGC_state_inuse:
BUG_ON(pg->count_info & PGC_broken);
- pg->count_info = PGC_state_free;
+ pg->count_info = PGC_state_free | (pg->count_info & PGC_preserved);
break;
case PGC_state_offlining:
- pg->count_info = (pg->count_info & PGC_broken) |
- PGC_state_offlined;
+ pg->count_info = (pg->count_info & PGC_preserved) | PGC_state_offlined;
pg_offlined = true;
break;
@@ -2366,7 +2366,7 @@ int assign_pages(
for ( i = 0; i < nr; i++ )
{
- ASSERT(!(pg[i].count_info & ~(PGC_extra | PGC_static)));
+ ASSERT(!(pg[i].count_info & ~PGC_preserved));
if ( pg[i].count_info & PGC_extra )
extra_pages++;
}
@@ -2426,7 +2426,7 @@ int assign_pages(
page_set_owner(&pg[i], d);
smp_wmb(); /* Domain pointer must be visible before updating refcnt. */
pg[i].count_info =
- (pg[i].count_info & (PGC_extra | PGC_static)) | PGC_allocated | 1;
+ (pg[i].count_info & PGC_preserved) | PGC_allocated | 1;
page_list_add_tail(&pg[i], page_to_list(d, &pg[i]));
}
@@ -2485,6 +2485,14 @@ struct page_info *alloc_domheap_pages(
}
if ( assign_page(pg, order, d, memflags) )
{
+ if ( memflags & MEMF_no_refcount )
+ {
+ unsigned long i;
+
+ for ( i = 0; i < (1UL << order); i++ )
+ pg[i].count_info &= ~PGC_extra;
+ }
+
free_heap_pages(pg, order, memflags & MEMF_no_scrub);
return NULL;
}
@@ -2539,6 +2547,7 @@ void free_domheap_pages(struct page_info *pg, unsigned int order)
{
ASSERT(d->extra_pages);
d->extra_pages--;
+ pg[i].count_info &= ~PGC_extra;
}
}
PGC_static and PGC_extra needs to be preserved when assigning a page. Define a new macro that groups those flags and use it instead of or'ing every time. To make preserved flags even more meaningful, they are kept also when switching state in mark_page_free(). Enforce the removal of PGC_extra before freeing new pages as this is considered an error and can cause ASSERT violations. Signed-off-by: Carlo Nonato <carlo.nonato@minervasys.tech> --- v9: - add PGC_broken to PGC_preserved - clear PGC_extra in alloc_domheap_pages() only if MEMF_no_refcount is set v8: - fixed PGC_extra ASSERT fail in alloc_domheap_pages() by removing PGC_extra before freeing v7: - PGC_preserved used also in mark_page_free() v6: - preserved_flags renamed to PGC_preserved - PGC_preserved is used only in assign_pages() v5: - new patch --- xen/common/page_alloc.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-)