git: fe9670298c07 - stable/13 - amd64: Handle 1GB mappings in pmap_enter_quick_locked()

The branch stable/13 has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=fe9670298c0792f6b14d7a8772b11c74eef4461d

commit fe9670298c0792f6b14d7a8772b11c74eef4461d
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2022-09-24 13:20:29 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2022-10-01 15:33:49 +0000

    amd64: Handle 1GB mappings in pmap_enter_quick_locked()
    
    This code path can be triggered by applying MADV_WILLNEED to a 1GB
    mapping.
    
    Reviewed by:    alc, kib
    
    (cherry picked from commit 6c2e9f4c32a44f3c239aba346322d871097eaed0)
---
 sys/amd64/amd64/pmap.c | 39 ++++++++++++++++++++++-----------------
 1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index 5288cd7fbfef..aa3774524023 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -7404,8 +7404,9 @@ pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, vm_page_t m,
 	 * resident, we are creating it here.
 	 */
 	if (va < VM_MAXUSER_ADDRESS) {
+		pdp_entry_t *pdpe;
+		pd_entry_t *pde;
 		vm_pindex_t ptepindex;
-		pd_entry_t *ptepa;
 
 		/*
 		 * Calculate pagetable page index
@@ -7414,31 +7415,35 @@ pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, vm_page_t m,
 		if (mpte && (mpte->pindex == ptepindex)) {
 			mpte->ref_count++;
 		} else {
-			/*
-			 * Get the page directory entry
-			 */
-			ptepa = pmap_pde(pmap, va);
-
 			/*
 			 * If the page table page is mapped, we just increment
 			 * the hold count, and activate it.  Otherwise, we
-			 * attempt to allocate a page table page.  If this
-			 * attempt fails, we don't retry.  Instead, we give up.
+			 * attempt to allocate a page table page, passing NULL
+			 * instead of the PV list lock pointer because we don't
+			 * intend to sleep.  If this attempt fails, we don't
+			 * retry.  Instead, we give up.
 			 */
-			if (ptepa && (*ptepa & PG_V) != 0) {
-				if (*ptepa & PG_PS)
+			pdpe = pmap_pdpe(pmap, va);
+			if (pdpe != NULL && (*pdpe & PG_V) != 0) {
+				if ((*pdpe & PG_PS) != 0)
 					return (NULL);
-				mpte = PHYS_TO_VM_PAGE(*ptepa & PG_FRAME);
-				mpte->ref_count++;
+				pde = pmap_pdpe_to_pde(pdpe, va);
+				if ((*pde & PG_V) != 0) {
+					if ((*pde & PG_PS) != 0)
+						return (NULL);
+					mpte = PHYS_TO_VM_PAGE(*pde & PG_FRAME);
+					mpte->ref_count++;
+				} else {
+					mpte = pmap_allocpte_alloc(pmap,
+					    ptepindex, NULL, va);
+					if (mpte == NULL)
+						return (NULL);
+				}
 			} else {
-				/*
-				 * Pass NULL instead of the PV list lock
-				 * pointer, because we don't intend to sleep.
-				 */
 				mpte = pmap_allocpte_alloc(pmap, ptepindex,
 				    NULL, va);
 				if (mpte == NULL)
-					return (mpte);
+					return (NULL);
 			}
 		}
 		pte = (pt_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(mpte));