diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2024-07-12 00:27:46 +0200 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2024-07-26 20:46:14 +0200 |
commit | 7fbdda31b0a14ff45809fb27182b98dcbcbad5b0 (patch) | |
tree | 9a8e0413f557c22fd713e8741a342705bf7cb996 /virt/kvm | |
parent | KVM: guest_memfd: delay folio_mark_uptodate() until after successful preparation (diff) | |
download | linux-7fbdda31b0a14ff45809fb27182b98dcbcbad5b0.tar.xz linux-7fbdda31b0a14ff45809fb27182b98dcbcbad5b0.zip |
KVM: guest_memfd: do not go through struct page
We have a perfectly usable folio, use it to retrieve the pfn and order.
All that's needed is a version of folio_file_page that returns a pfn.
Reviewed-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'virt/kvm')
-rw-r--r-- | virt/kvm/guest_memfd.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index 1ea632dbae57..5221b584288f 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -13,6 +13,18 @@ struct kvm_gmem { struct list_head entry; }; +/** + * folio_file_pfn - like folio_file_page, but return a pfn. + * @folio: The folio which contains this index. + * @index: The index we want to look up. + * + * Return: The pfn for this index. + */ +static inline kvm_pfn_t folio_file_pfn(struct folio *folio, pgoff_t index) +{ + return folio_pfn(folio) + (index & (folio_nr_pages(folio) - 1)); +} + static int kvm_gmem_prepare_folio(struct inode *inode, pgoff_t index, struct folio *folio) { #ifdef CONFIG_HAVE_KVM_GMEM_PREPARE @@ -22,7 +34,6 @@ static int kvm_gmem_prepare_folio(struct inode *inode, pgoff_t index, struct fol list_for_each_entry(gmem, gmem_list, entry) { struct kvm_memory_slot *slot; struct kvm *kvm = gmem->kvm; - struct page *page; kvm_pfn_t pfn; gfn_t gfn; int rc; @@ -34,13 +45,12 @@ static int kvm_gmem_prepare_folio(struct inode *inode, pgoff_t index, struct fol if (!slot) continue; - page = folio_file_page(folio, index); - pfn = page_to_pfn(page); + pfn = folio_file_pfn(folio, index); gfn = slot->base_gfn + index - slot->gmem.pgoff; - rc = kvm_arch_gmem_prepare(kvm, gfn, pfn, compound_order(compound_head(page))); + rc = kvm_arch_gmem_prepare(kvm, gfn, pfn, folio_order(folio)); if (rc) { - pr_warn_ratelimited("gmem: Failed to prepare folio for index %lx GFN %llx PFN %llx error %d.\n", - index, gfn, pfn, rc); + pr_warn_ratelimited("gmem: Failed to prepare folio for GFN %llx PFN %llx error %d.\n", + gfn, pfn, rc); return rc; } } @@ -548,7 +558,6 @@ __kvm_gmem_get_pfn(struct file *file, struct kvm_memory_slot *slot, pgoff_t index = gfn - slot->base_gfn + slot->gmem.pgoff; struct kvm_gmem *gmem = file->private_data; struct folio *folio; - struct page *page; if (file != slot->gmem.file) { WARN_ON_ONCE(slot->gmem.file); @@ -571,9 +580,7 @@ __kvm_gmem_get_pfn(struct file *file, struct kvm_memory_slot *slot, return ERR_PTR(-EHWPOISON); } - page = folio_file_page(folio, index); - - *pfn = page_to_pfn(page); + *pfn = folio_file_pfn(folio, index); if (max_order) *max_order = 0; |