Straight-forward extension of existing code to support additional page
table level.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
arch/x86/mm/pageattr.c | 54 +++++++++++++++++++++++++++++++++++++-------------
1 file changed, 40 insertions(+), 14 deletions(-)
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index a57e8e02f457..56b22fa504df 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -346,6 +346,7 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address,
pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
unsigned int *level)
{
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
@@ -354,7 +355,15 @@ pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
if (pgd_none(*pgd))
return NULL;
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (p4d_none(*p4d))
+ return NULL;
+
+ *level = PG_LEVEL_512G;
+ if (p4d_large(*p4d) || !p4d_present(*p4d))
+ return (pte_t *)p4d;
+
+ pud = pud_offset(p4d, address);
if (pud_none(*pud))
return NULL;
@@ -406,13 +415,18 @@ static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
pmd_t *lookup_pmd_address(unsigned long address)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pgd = pgd_offset_k(address);
if (pgd_none(*pgd))
return NULL;
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (p4d_none(*p4d) || p4d_large(*p4d) || !p4d_present(*p4d))
+ return NULL;
+
+ pud = pud_offset(p4d, address);
if (pud_none(*pud) || pud_large(*pud) || !pud_present(*pud))
return NULL;
@@ -477,11 +491,13 @@ static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
list_for_each_entry(page, &pgd_list, lru) {
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pgd = (pgd_t *)page_address(page) + pgd_index(address);
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ pud = pud_offset(p4d, address);
pmd = pmd_offset(pud, address);
set_pte_atomic((pte_t *)pmd, pte);
}
@@ -836,9 +852,9 @@ static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
pud_clear(pud);
}
-static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end)
+static void unmap_pud_range(p4d_t *p4d, unsigned long start, unsigned long end)
{
- pud_t *pud = pud_offset(pgd, start);
+ pud_t *pud = pud_offset(p4d, start);
/*
* Not on a GB page boundary?
@@ -1004,8 +1020,8 @@ static long populate_pmd(struct cpa_data *cpa,
return num_pages;
}
-static long populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
- pgprot_t pgprot)
+static int populate_pud(struct cpa_data *cpa, unsigned long start, p4d_t *p4d,
+ pgprot_t pgprot)
{
pud_t *pud;
unsigned long end;
@@ -1026,7 +1042,7 @@ static long populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
cur_pages = (pre_end - start) >> PAGE_SHIFT;
cur_pages = min_t(int, (int)cpa->numpages, cur_pages);
- pud = pud_offset(pgd, start);
+ pud = pud_offset(p4d, start);
/*
* Need a PMD page?
@@ -1047,7 +1063,7 @@ static long populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
if (cpa->numpages == cur_pages)
return cur_pages;
- pud = pud_offset(pgd, start);
+ pud = pud_offset(p4d, start);
pud_pgprot = pgprot_4k_2_large(pgprot);
/*
@@ -1067,7 +1083,7 @@ static long populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
if (start < end) {
long tmp;
- pud = pud_offset(pgd, start);
+ pud = pud_offset(p4d, start);
if (pud_none(*pud))
if (alloc_pmd_page(pud))
return -1;
@@ -1090,33 +1106,43 @@ static int populate_pgd(struct cpa_data *cpa, unsigned long addr)
{
pgprot_t pgprot = __pgprot(_KERNPG_TABLE);
pud_t *pud = NULL; /* shut up gcc */
+ p4d_t *p4d;
pgd_t *pgd_entry;
long ret;
pgd_entry = cpa->pgd + pgd_index(addr);
+ if (pgd_none(*pgd_entry)) {
+ p4d = (p4d_t *)get_zeroed_page(GFP_KERNEL | __GFP_NOTRACK);
+ if (!p4d)
+ return -1;
+
+ set_pgd(pgd_entry, __pgd(__pa(p4d) | _KERNPG_TABLE));
+ }
+
/*
* Allocate a PUD page and hand it down for mapping.
*/
- if (pgd_none(*pgd_entry)) {
+ p4d = p4d_offset(pgd_entry, addr);
+ if (p4d_none(*p4d)) {
pud = (pud_t *)get_zeroed_page(GFP_KERNEL | __GFP_NOTRACK);
if (!pud)
return -1;
- set_pgd(pgd_entry, __pgd(__pa(pud) | _KERNPG_TABLE));
+ set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE));
}
pgprot_val(pgprot) &= ~pgprot_val(cpa->mask_clr);
pgprot_val(pgprot) |= pgprot_val(cpa->mask_set);
- ret = populate_pud(cpa, addr, pgd_entry, pgprot);
+ ret = populate_pud(cpa, addr, p4d, pgprot);
if (ret < 0) {
/*
* Leave the PUD page in place in case some other CPU or thread
* already found it, but remove any useless entries we just
* added to it.
*/
- unmap_pud_range(pgd_entry, addr,
+ unmap_pud_range(p4d, addr,
addr + (cpa->numpages << PAGE_SHIFT));
return ret;
}
--
2.11.0
