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| author |   Matthew Wilcox (Oracle) <willy@infradead.org> | 2024-01-11 15:24:20 +0000 |
|---|---|---|
| committer |   Andrew Morton <akpm@linux-foundation.org> | 2024-02-21 16:00:03 -0800 |
| commit | 5662400a9ac03f38ef3b84e4ff9a640a4604bef9 (patch) | |
| tree | 3d8fe5bcf455bf7bfaaba20d85c28e2fd0b50285 /include/linux/swapops.h | |
| parent | memcg: use a folio in get_mctgt_type_thp (diff) | |
| download | wireguard-linux-5662400a9ac03f38ef3b84e4ff9a640a4604bef9.tar.xz wireguard-linux-5662400a9ac03f38ef3b84e4ff9a640a4604bef9.zip | |
mm: add pfn_swap_entry_folio()
Patch series "mm: convert mm counter to take a folio", v3.
Make sure all mm_counter() and mm_counter_file() callers have a folio,
then convert mm counter functions to take a folio, which saves some
compound_head() calls.
This patch (of 10):
Thanks to the compound_head() hidden inside PageLocked(), this saves a
call to compound_head() over calling page_folio(pfn_swap_entry_to_page())
Link: https://lkml.kernel.org/r/20240111152429.3374566-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20240111152429.3374566-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux/swapops.h')
| -rw-r--r-- | include/linux/swapops.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/include/linux/swapops.h b/include/linux/swapops.h index bff1e8d97de0..48b700ba1d18 100644 --- a/include/linux/swapops.h +++ b/include/linux/swapops.h @@ -468,6 +468,19 @@ static inline struct page *pfn_swap_entry_to_page(swp_entry_t entry) return p; } +static inline struct folio *pfn_swap_entry_folio(swp_entry_t entry) +{ + struct folio *folio = pfn_folio(swp_offset_pfn(entry)); + + /* + * Any use of migration entries may only occur while the + * corresponding folio is locked + */ + BUG_ON(is_migration_entry(entry) && !folio_test_locked(folio)); + + return folio; +} + /* * A pfn swap entry is a special type of swap entry that always has a pfn stored * in the swap offset. They are used to represent unaddressable device memory |