The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=7773023b72de19c6c9a47fd04ac955ec52773f0f
commit 7773023b72de19c6c9a47fd04ac955ec52773f0f Author: Konstantin Belousov <[email protected]> AuthorDate: 2024-07-07 23:26:57 +0000 Commit: Konstantin Belousov <[email protected]> CommitDate: 2024-07-15 06:15:53 +0000 DMAR pagetables pages: handle ref_count special references Preserve object reference and block bit during refcount arithmetic and obliteration, by using vm_page_wire()/unwire_noq(). Reviewed by: markj Sponsored by: Advanced Micro Devices (AMD) Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D45910 --- sys/x86/iommu/intel_idpgtbl.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/sys/x86/iommu/intel_idpgtbl.c b/sys/x86/iommu/intel_idpgtbl.c index 157afaec75ef..de38a6fece94 100644 --- a/sys/x86/iommu/intel_idpgtbl.c +++ b/sys/x86/iommu/intel_idpgtbl.c @@ -47,6 +47,7 @@ #include <sys/tree.h> #include <sys/uio.h> #include <sys/vmem.h> +#include <sys/vmmeter.h> #include <vm/vm.h> #include <vm/vm_extern.h> #include <vm/vm_kern.h> @@ -390,7 +391,7 @@ retry: * pte write and clean while the lock is * dropped. */ - m->ref_count++; + vm_page_wire(m); sfp = NULL; ptep = domain_pgtbl_map_pte(domain, base, lvl - 1, @@ -398,7 +399,7 @@ retry: if (ptep == NULL) { KASSERT(m->pindex != 0, ("loosing root page %p", domain)); - m->ref_count--; + vm_page_unwire_noq(m); iommu_pgfree(domain->pgtbl_obj, m->pindex, flags); return (NULL); @@ -406,8 +407,8 @@ retry: dmar_pte_store(&ptep->pte, DMAR_PTE_R | DMAR_PTE_W | VM_PAGE_TO_PHYS(m)); dmar_flush_pte_to_ram(domain->dmar, ptep); - sf_buf_page(sfp)->ref_count += 1; - m->ref_count--; + vm_page_wire(sf_buf_page(sfp)); + vm_page_unwire_noq(m); iommu_unmap_pgtbl(sfp); /* Only executed once. */ goto retry; @@ -486,7 +487,7 @@ domain_map_buf_locked(struct dmar_domain *domain, iommu_gaddr_t base, dmar_pte_store(&pte->pte, VM_PAGE_TO_PHYS(ma[pi]) | pflags | (superpage ? DMAR_PTE_SP : 0)); dmar_flush_pte_to_ram(domain->dmar, pte); - sf_buf_page(sf)->ref_count += 1; + vm_page_wire(sf_buf_page(sf)); } if (sf != NULL) iommu_unmap_pgtbl(sf); @@ -592,8 +593,7 @@ domain_unmap_clear_pte(struct dmar_domain *domain, iommu_gaddr_t base, int lvl, iommu_unmap_pgtbl(*sf); *sf = NULL; } - m->ref_count--; - if (m->ref_count != 0) + if (!vm_page_unwire_noq(m)) return; KASSERT(lvl != 0, ("lost reference (lvl) on root pg domain %p base %jx lvl %d", @@ -709,7 +709,7 @@ domain_alloc_pgtbl(struct dmar_domain *domain) m = iommu_pgalloc(domain->pgtbl_obj, 0, IOMMU_PGF_WAITOK | IOMMU_PGF_ZERO | IOMMU_PGF_OBJL); /* No implicit free of the top level page table page. */ - m->ref_count = 1; + vm_page_wire(m); DMAR_DOMAIN_PGUNLOCK(domain); DMAR_LOCK(domain->dmar); domain->iodom.flags |= IOMMU_DOMAIN_PGTBL_INITED; @@ -741,8 +741,10 @@ domain_free_pgtbl(struct dmar_domain *domain) /* Obliterate ref_counts */ VM_OBJECT_ASSERT_WLOCKED(obj); - for (m = vm_page_lookup(obj, 0); m != NULL; m = vm_page_next(m)) - m->ref_count = 0; + for (m = vm_page_lookup(obj, 0); m != NULL; m = vm_page_next(m)) { + vm_page_clearref(m); + vm_wire_sub(1); + } VM_OBJECT_WUNLOCK(obj); vm_object_deallocate(obj); }
