The patch titled
Subject: lib/test_hmm: make dmirror_atomic_map() consume a single page
has been added to the -mm mm-unstable branch. Its filename is
lib-test_hmm-make-dmirror_atomic_map-consume-a-single-page.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-test_hmm-make-dmirror_atomic_map-consume-a-single-page.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: lib/test_hmm: make dmirror_atomic_map() consume a single page
Date: Wed, 26 Feb 2025 14:22:53 +0100
Patch series "mm: cleanups for device-exclusive entries (hmm)", v2.
Some smaller device-exclusive cleanups I have lying around.
This patch (of 5):
The caller now always passes a single page; let's simplify, and return "0"
on success.
Link: https://lkml.kernel.org/r/20250226132257.2826043-1-david@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20250226132257.2826043-2-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Alistair Popple <apopple@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Jérôme Glisse <jglisse@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/test_hmm.c | 32 ++++++++++----------------------
1 file changed, 10 insertions(+), 22 deletions(-)
--- a/lib/test_hmm.c~lib-test_hmm-make-dmirror_atomic_map-consume-a-single-page
+++ a/lib/test_hmm.c
@@ -707,34 +707,23 @@ static int dmirror_check_atomic(struct d
return 0;
}
-static int dmirror_atomic_map(unsigned long start, unsigned long end,
- struct page **pages, struct dmirror *dmirror)
+static int dmirror_atomic_map(unsigned long addr, struct page *page,
+ struct dmirror *dmirror)
{
- unsigned long pfn, mapped = 0;
- int i;
+ void *entry;
/* Map the migrated pages into the device's page tables. */
mutex_lock(&dmirror->mutex);
- for (i = 0, pfn = start >> PAGE_SHIFT; pfn < (end >> PAGE_SHIFT); pfn++, i++) {
- void *entry;
-
- if (!pages[i])
- continue;
-
- entry = pages[i];
- entry = xa_tag_pointer(entry, DPT_XA_TAG_ATOMIC);
- entry = xa_store(&dmirror->pt, pfn, entry, GFP_ATOMIC);
- if (xa_is_err(entry)) {
- mutex_unlock(&dmirror->mutex);
- return xa_err(entry);
- }
-
- mapped++;
+ entry = xa_tag_pointer(page, DPT_XA_TAG_ATOMIC);
+ entry = xa_store(&dmirror->pt, addr >> PAGE_SHIFT, entry, GFP_ATOMIC);
+ if (xa_is_err(entry)) {
+ mutex_unlock(&dmirror->mutex);
+ return xa_err(entry);
}
mutex_unlock(&dmirror->mutex);
- return mapped;
+ return 0;
}
static int dmirror_migrate_finalize_and_map(struct migrate_vma *args,
@@ -804,8 +793,7 @@ static int dmirror_exclusive(struct dmir
break;
}
- ret = dmirror_atomic_map(addr, addr + PAGE_SIZE, &page, dmirror);
- ret = ret == 1 ? 0 : -EBUSY;
+ ret = dmirror_atomic_map(addr, page, dmirror);
folio_unlock(folio);
folio_put(folio);
}
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-gup-reject-foll_split_pmd-with-hugetlb-vmas.patch
mm-rmap-reject-hugetlb-folios-in-folio_make_device_exclusive.patch
mm-rmap-convert-make_device_exclusive_range-to-make_device_exclusive.patch
mm-rmap-convert-make_device_exclusive_range-to-make_device_exclusive-fix.patch
mm-rmap-implement-make_device_exclusive-using-folio_walk-instead-of-rmap-walk.patch
mm-memory-detect-writability-in-restore_exclusive_pte-through-can_change_pte_writable.patch
mm-use-single-swp_device_exclusive-entry-type.patch
mm-page_vma_mapped-device-exclusive-entries-are-not-migration-entries.patch
kernel-events-uprobes-handle-device-exclusive-entries-correctly-in-__replace_page.patch
mm-ksm-handle-device-exclusive-entries-correctly-in-write_protect_page.patch
mm-rmap-handle-device-exclusive-entries-correctly-in-try_to_unmap_one.patch
mm-rmap-handle-device-exclusive-entries-correctly-in-try_to_migrate_one.patch
mm-rmap-handle-device-exclusive-entries-correctly-in-page_vma_mkclean_one.patch
mm-page_idle-handle-device-exclusive-entries-correctly-in-page_idle_clear_pte_refs_one.patch
mm-damon-handle-device-exclusive-entries-correctly-in-damon_folio_young_one.patch
mm-damon-handle-device-exclusive-entries-correctly-in-damon_folio_mkold_one.patch
mm-rmap-keep-mapcount-untouched-for-device-exclusive-entries.patch
mm-rmap-avoid-ebusy-from-make_device_exclusive.patch
lib-test_hmm-make-dmirror_atomic_map-consume-a-single-page.patch
mm-memory-remove-pageanonexclusive-sanity-check-in-restore_exclusive_pte.patch
mm-memory-pass-folio-and-pte-to-restore_exclusive_pte.patch
mm-memory-document-restore_exclusive_pte.patch
mm-mmu_notifier-use-mmu_notify_clear-in-remove_device_exclusive_entry.patch
