On Tue, 21 Jan 2014, Zoltan Kiss wrote:It removes a stray space from the original code. Not necessary, but if it's there, I think we can keep it.@@ -121,7 +125,7 @@ static inline unsigned long mfn_to_pfn(unsigned long mfn)
pfn = m2p_find_override_pfn(mfn, ~0);
}
- /*
+ /*
Spurious change?
Yes, because that page_to_pfn can return something different. That's why the v2 patches failed.diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index 2ae8699..0060178 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -872,15 +872,13 @@ static unsigned long mfn_hash(unsigned long mfn)
/* Add an MFN override for a particular page */
int m2p_add_override(unsigned long mfn, struct page *page,
- struct gnttab_map_grant_ref *kmap_op)
+ struct gnttab_map_grant_ref *kmap_op, unsigned long pfn)
Do we really need to add another additional parameter to
m2p_add_override?
I would just let m2p_add_override and m2p_remove_override call
page_to_pfn again. It is not that expensive.
Same as above.@@ -933,20 +924,15 @@ int m2p_add_override(unsigned long mfn, struct page *page,
}
EXPORT_SYMBOL_GPL(m2p_add_override);
int m2p_remove_override(struct page *page,
- struct gnttab_map_grant_ref *kmap_op)
+ struct gnttab_map_grant_ref *kmap_op,
+ unsigned long pfn,
+ unsigned long mfn)
Same here
And ret = -ENOMEM@@ -927,8 +931,18 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
} else {
mfn = PFN_DOWN(map_ops[i].dev_bus_addr);
}
- ret = m2p_add_override(mfn, pages[i], kmap_ops ?
- &kmap_ops[i] : NULL);
+ pfn = page_to_pfn(pages[i]);
+
+ WARN_ON(PagePrivate(pages[i]));
+ SetPagePrivate(pages[i]);
+ set_page_private(pages[i], mfn);
+
+ pages[i]->index = pfn_to_mfn(pfn);
+ if (unlikely(!set_phys_to_machine(pfn, FOREIGN_FRAME(mfn))))
+ return -ENOMEM;
goto out
I'll fix that. Also in unmap.
+ if (m2p_override)
+ ret = m2p_add_override(mfn, pages[i], kmap_ops ?
+ &kmap_ops[i] : NULL, pfn);
if (ret)
goto out;
}
@@ -937,17 +951,34 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
if (lazy)
arch_leave_lazy_mmu_mode();
- return ret;
+ return 0;
We are loosing the error code possibly returned by m2p_add_override and
the previous check.
And ret = -EINVAL@@ -958,17 +989,32 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
set_phys_to_machine(unmap_ops[i].host_addr >> PAGE_SHIFT,
INVALID_P2M_ENTRY);
}
- return ret;
+ return 0;
}
- if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
+ if (m2p_override &&
+ !in_interrupt() &&
+ paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
arch_enter_lazy_mmu_mode();
lazy = true;
}
for (i = 0; i < count; i++) {
- ret = m2p_remove_override(pages[i], kmap_ops ?
- &kmap_ops[i] : NULL);
+ pfn = page_to_pfn(pages[i]);
+ mfn = get_phys_to_machine(pfn);
+ if (mfn == INVALID_P2M_ENTRY || !(mfn & FOREIGN_FRAME_BIT))
+ return -EINVAL;
goto out