# HG changeset patch
# User Alex Williamson <alex.williamson@xxxxxx>
# Date 1181659682 21600
# Node ID 13d5a4ad57d00d063126fd009f28354f45ac1be5
# Parent 2d72521fbdfddbfc53bcd9cb4b293a762ddd2905
[IA64] Implement gnttab replace_and_unmap
Signed-off-by: Isaku Yamahata <yamahata@xxxxxxxxxxxxx>
---
xen/arch/ia64/xen/mm.c | 64 +++++++++++++++++++++++++++++++------
xen/include/asm-ia64/grant_table.h | 2 -
2 files changed, 56 insertions(+), 10 deletions(-)
diff -r 2d72521fbdfd -r 13d5a4ad57d0 xen/arch/ia64/xen/mm.c
--- a/xen/arch/ia64/xen/mm.c Tue Jun 12 08:39:24 2007 -0600
+++ b/xen/arch/ia64/xen/mm.c Tue Jun 12 08:48:02 2007 -0600
@@ -1547,13 +1547,55 @@ replace_grant_host_mapping(unsigned long
volatile pte_t* pte;
unsigned long cur_arflags;
pte_t cur_pte;
- pte_t new_pte;
+ pte_t new_pte = __pte(0);
pte_t old_pte;
struct page_info* page = mfn_to_page(mfn);
+ struct page_info* new_page = NULL;
+ volatile pte_t* new_page_pte = NULL;
if (new_gpaddr) {
- gdprintk(XENLOG_INFO, "%s: new_gpaddr 0x%lx\n", __func__, new_gpaddr);
- return GNTST_general_error;
+ new_page_pte = lookup_noalloc_domain_pte_none(d, new_gpaddr);
+ if (likely(new_page_pte != NULL)) {
+ new_pte = ptep_get_and_clear(&d->arch.mm,
+ new_gpaddr, new_page_pte);
+ if (likely(pte_present(new_pte))) {
+ unsigned long new_page_mfn;
+ struct domain* page_owner;
+
+ new_page_mfn = pte_pfn(new_pte);
+ new_page = mfn_to_page(new_page_mfn);
+ page_owner = page_get_owner(new_page);
+ if (unlikely(page_owner == NULL)) {
+ gdprintk(XENLOG_INFO,
+ "%s: page_owner == NULL "
+ "gpaddr 0x%lx mfn 0x%lx "
+ "new_gpaddr 0x%lx mfn 0x%lx\n",
+ __func__, gpaddr, mfn, new_gpaddr, new_page_mfn);
+ new_page = NULL; /* prevent domain_put_page() */
+ goto out;
+ }
+
+ /*
+ * domain_put_page(clear_PGC_allcoated = 0)
+ * doesn't decrement refcount of page with
+ * pte_ptc_allocated() = 1. Be carefull.
+ */
+ if (unlikely(!pte_pgc_allocated(new_pte))) {
+ /* domain_put_page() decrements page refcount. adjust it.
*/
+ if (get_page(new_page, page_owner)) {
+ gdprintk(XENLOG_INFO,
+ "%s: get_page() failed. "
+ "gpaddr 0x%lx mfn 0x%lx "
+ "new_gpaddr 0x%lx mfn 0x%lx\n",
+ __func__, gpaddr, mfn,
+ new_gpaddr, new_page_mfn);
+ goto out;
+ }
+ }
+ domain_put_page(d, new_gpaddr, new_page_pte, new_pte, 0);
+ } else
+ new_pte = __pte(0);
+ }
}
if (flags & (GNTMAP_application_map | GNTMAP_contains_pte)) {
@@ -1565,7 +1607,7 @@ replace_grant_host_mapping(unsigned long
if (pte == NULL) {
gdprintk(XENLOG_INFO, "%s: gpaddr 0x%lx mfn 0x%lx\n",
__func__, gpaddr, mfn);
- return GNTST_general_error;
+ goto out;
}
again:
@@ -1575,16 +1617,15 @@ replace_grant_host_mapping(unsigned long
(page_get_owner(page) == d && get_gpfn_from_mfn(mfn) == gpfn)) {
gdprintk(XENLOG_INFO, "%s: gpaddr 0x%lx mfn 0x%lx cur_pte 0x%lx\n",
__func__, gpaddr, mfn, pte_val(cur_pte));
- return GNTST_general_error;
- }
- new_pte = __pte(0);
+ goto out;
+ }
old_pte = ptep_cmpxchg_rel(&d->arch.mm, gpaddr, pte, cur_pte, new_pte);
if (unlikely(!pte_present(old_pte))) {
gdprintk(XENLOG_INFO, "%s: gpaddr 0x%lx mfn 0x%lx"
" cur_pte 0x%lx old_pte 0x%lx\n",
__func__, gpaddr, mfn, pte_val(cur_pte), pte_val(old_pte));
- return GNTST_general_error;
+ goto out;
}
if (unlikely(pte_val(cur_pte) != pte_val(old_pte))) {
if (pte_pfn(old_pte) == mfn) {
@@ -1593,7 +1634,7 @@ replace_grant_host_mapping(unsigned long
gdprintk(XENLOG_INFO, "%s gpaddr 0x%lx mfn 0x%lx cur_pte "
"0x%lx old_pte 0x%lx\n",
__func__, gpaddr, mfn, pte_val(cur_pte), pte_val(old_pte));
- return GNTST_general_error;
+ goto out;
}
BUG_ON(pte_pfn(old_pte) != mfn);
@@ -1605,6 +1646,11 @@ replace_grant_host_mapping(unsigned long
perfc_incr(replace_grant_host_mapping);
return GNTST_okay;
+
+ out:
+ if (new_page)
+ domain_put_page(d, new_gpaddr, new_page_pte, new_pte, 1);
+ return GNTST_general_error;
}
// heavily depends on the struct page layout.
diff -r 2d72521fbdfd -r 13d5a4ad57d0 xen/include/asm-ia64/grant_table.h
--- a/xen/include/asm-ia64/grant_table.h Tue Jun 12 08:39:24 2007 -0600
+++ b/xen/include/asm-ia64/grant_table.h Tue Jun 12 08:48:02 2007 -0600
@@ -69,7 +69,7 @@ static inline void gnttab_clear_flag(uns
static inline int replace_grant_supported(void)
{
- return 0;
+ return 1;
}
#endif /* __ASM_GRANT_TABLE_H__ */
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