From ac3a7092ebcb011759cba39a259f7193e4f6ba62 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 9 Nov 2018 12:07:06 +0100 Subject: 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: Joerg Roedel --- drivers/iommu/amd_iommu.c | 144 ++++++++++++++++++++++++++-------------------- 1 file changed, 83 insertions(+), 61 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 1167ff0416cf..2655bd91af93 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -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; -- cgit v1.2.3