Commit ac3a7092 authored by Joerg Roedel's avatar Joerg Roedel
Browse files

iommu/amd: Collect page-table pages in freelist 



Collect all pages that belong to a page-table in a list and
free them after the tree has been traversed. This allows to
implement safer page-table updates in subsequent patches.
Also move the functions for page-table freeing a bit upwards
in the file so that they are usable from the iommu_map() path.

Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent ccda4af0

drivers/iommu/amd_iommu.c

+83 −61
Original line number Diff line number Diff line
@@ -1317,6 +1317,89 @@ static void domain_flush_devices(struct protection_domain *domain) 
 *

 ****************************************************************************/



static void free_page_list(struct page *freelist)

{

	while (freelist != NULL) {

		unsigned long p = (unsigned long)page_address(freelist);

		freelist = freelist->freelist;

		free_page(p);

	}

}



static struct page *free_pt_page(unsigned long pt, struct page *freelist)

{

	struct page *p = virt_to_page((void *)pt);



	p->freelist = freelist;



	return p;

}



#define DEFINE_FREE_PT_FN(LVL, FN)						\

static struct page *free_pt_##LVL (unsigned long __pt, struct page *freelist)	\

{										\

	unsigned long p;							\

	u64 *pt;								\

	int i;									\

										\

	pt = (u64 *)__pt;							\

										\

	for (i = 0; i < 512; ++i) {						\

		/* PTE present? */						\

		if (!IOMMU_PTE_PRESENT(pt[i]))					\

			continue;						\

										\

		/* Large PTE? */						\

		if (PM_PTE_LEVEL(pt[i]) == 0 ||					\

		    PM_PTE_LEVEL(pt[i]) == 7)					\

			continue;						\

										\

		p = (unsigned long)IOMMU_PTE_PAGE(pt[i]);			\

		freelist = FN(p, freelist);					\

	}									\

										\

	return free_pt_page((unsigned long)pt, freelist);			\

}



DEFINE_FREE_PT_FN(l2, free_pt_page)

DEFINE_FREE_PT_FN(l3, free_pt_l2)

DEFINE_FREE_PT_FN(l4, free_pt_l3)

DEFINE_FREE_PT_FN(l5, free_pt_l4)

DEFINE_FREE_PT_FN(l6, free_pt_l5)



static void free_pagetable(struct protection_domain *domain)

{

	unsigned long root = (unsigned long)domain->pt_root;

	struct page *freelist = NULL;



	switch (domain->mode) {

	case PAGE_MODE_NONE:

		break;

	case PAGE_MODE_1_LEVEL:

		freelist = free_pt_page(root, freelist);

		break;

	case PAGE_MODE_2_LEVEL:

		freelist = free_pt_l2(root, freelist);

		break;

	case PAGE_MODE_3_LEVEL:

		freelist = free_pt_l3(root, freelist);

		break;

	case PAGE_MODE_4_LEVEL:

		freelist = free_pt_l4(root, freelist);

		break;

	case PAGE_MODE_5_LEVEL:

		freelist = free_pt_l5(root, freelist);

		break;

	case PAGE_MODE_6_LEVEL:

		freelist = free_pt_l6(root, freelist);

		break;

	default:

		BUG();

	}



	free_page_list(freelist);

}



/*

 * This function is used to add another level to an IO page table. Adding

 * another level increases the size of the address space by 9 bits to a size up
@@ -1638,67 +1721,6 @@ static void domain_id_free(int id) 
	spin_unlock(&pd_bitmap_lock);

}



#define DEFINE_FREE_PT_FN(LVL, FN)				\

static void free_pt_##LVL (unsigned long __pt)			\

{								\

	unsigned long p;					\

	u64 *pt;						\

	int i;							\

								\

	pt = (u64 *)__pt;					\

								\

	for (i = 0; i < 512; ++i) {				\

		/* PTE present? */				\

		if (!IOMMU_PTE_PRESENT(pt[i]))			\

			continue;				\

								\

		/* Large PTE? */				\

		if (PM_PTE_LEVEL(pt[i]) == 0 ||			\

		    PM_PTE_LEVEL(pt[i]) == 7)			\

			continue;				\

								\

		p = (unsigned long)IOMMU_PTE_PAGE(pt[i]);	\

		FN(p);						\

	}							\

	free_page((unsigned long)pt);				\

}



DEFINE_FREE_PT_FN(l2, free_page)

DEFINE_FREE_PT_FN(l3, free_pt_l2)

DEFINE_FREE_PT_FN(l4, free_pt_l3)

DEFINE_FREE_PT_FN(l5, free_pt_l4)

DEFINE_FREE_PT_FN(l6, free_pt_l5)



static void free_pagetable(struct protection_domain *domain)

{

	unsigned long root = (unsigned long)domain->pt_root;



	switch (domain->mode) {

	case PAGE_MODE_NONE:

		break;

	case PAGE_MODE_1_LEVEL:

		free_page(root);

		break;

	case PAGE_MODE_2_LEVEL:

		free_pt_l2(root);

		break;

	case PAGE_MODE_3_LEVEL:

		free_pt_l3(root);

		break;

	case PAGE_MODE_4_LEVEL:

		free_pt_l4(root);

		break;

	case PAGE_MODE_5_LEVEL:

		free_pt_l5(root);

		break;

	case PAGE_MODE_6_LEVEL:

		free_pt_l6(root);

		break;

	default:

		BUG();

	}

}



static void free_gcr3_tbl_level1(u64 *tbl)

{

	u64 *ptr;

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