Commit 8c595088 authored by Konrad Rzeszutek Wilk's avatar Konrad Rzeszutek Wilk
Browse files

xen/p2m: Create entries in the P2M_MFN trees's to track 1-1 mappings 



.. when applicable. We need to track in the p2m_mfn and
p2m_mfn_p the MFNs and pointers, respectivly, for the P2M entries
that are allocated for the identity mappings. Without this,
a PV domain with an E820 that triggers the 1-1 mapping to kick in,
won't be able to be restored as the P2M won't have the identity
mappings.

Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent 0ce790e7

arch/x86/xen/p2m.c

+28 −2
Original line number Diff line number Diff line
@@ -522,11 +522,20 @@ static bool __init __early_alloc_p2m(unsigned long pfn) 
	/* Boundary cross-over for the edges: */

	if (idx) {

		unsigned long *p2m = extend_brk(PAGE_SIZE, PAGE_SIZE);

		unsigned long *mid_mfn_p;



		p2m_init(p2m);



		p2m_top[topidx][mididx] = p2m;



		/* For save/restore we need to MFN of the P2M saved */

		

		mid_mfn_p = p2m_top_mfn_p[topidx];

		WARN(mid_mfn_p[mididx] != virt_to_mfn(p2m_missing),

			"P2M_TOP_P[%d][%d] != MFN of p2m_missing!\n",

			topidx, mididx);

		mid_mfn_p[mididx] = virt_to_mfn(p2m);



	}

	return idx != 0;

}
@@ -549,12 +558,29 @@ unsigned long __init set_phys_range_identity(unsigned long pfn_s, 
		pfn += P2M_MID_PER_PAGE * P2M_PER_PAGE)

	{

		unsigned topidx = p2m_top_index(pfn);

		if (p2m_top[topidx] == p2m_mid_missing) {

			unsigned long **mid = extend_brk(PAGE_SIZE, PAGE_SIZE);

		unsigned long *mid_mfn_p;

		unsigned long **mid;



		mid = p2m_top[topidx];

		mid_mfn_p = p2m_top_mfn_p[topidx];

		if (mid == p2m_mid_missing) {

			mid = extend_brk(PAGE_SIZE, PAGE_SIZE);



			p2m_mid_init(mid);



			p2m_top[topidx] = mid;



			BUG_ON(mid_mfn_p != p2m_mid_missing_mfn);

		}

		/* And the save/restore P2M tables.. */

		if (mid_mfn_p == p2m_mid_missing_mfn) {

			mid_mfn_p = extend_brk(PAGE_SIZE, PAGE_SIZE);

			p2m_mid_mfn_init(mid_mfn_p);



			p2m_top_mfn_p[topidx] = mid_mfn_p;

			p2m_top_mfn[topidx] = virt_to_mfn(mid_mfn_p);

			/* Note: we don't set mid_mfn_p[midix] here,

		 	 * look in __early_alloc_p2m */

		}

	}

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