On 12/16/2024 7:53 AM, Matthew Wilcox (Oracle) wrote:
Convert from pfn to folio instead of page and use those folios
throughout to avoid accesses to page->index and page->mapping.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
fs/dax.c | 53 +++++++++++++++++++++++++++--------------------------
1 file changed, 27 insertions(+), 26 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 21b47402b3dc..972febc6fb9d 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -320,38 +320,39 @@ static unsigned long dax_end_pfn(void *entry)
for (pfn = dax_to_pfn(entry); \
pfn < dax_end_pfn(entry); pfn++)
-static inline bool dax_page_is_shared(struct page *page)
+static inline bool dax_folio_is_shared(struct folio *folio)
{
- return page->mapping == PAGE_MAPPING_DAX_SHARED;
+ return folio->mapping == PAGE_MAPPING_DAX_SHARED;
}
/*
- * Set the page->mapping with PAGE_MAPPING_DAX_SHARED flag, increase the
+ * Set the folio->mapping with PAGE_MAPPING_DAX_SHARED flag, increase the
* refcount.
*/
-static inline void dax_page_share_get(struct page *page)
+static inline void dax_folio_share_get(struct folio *folio)
{
- if (page->mapping != PAGE_MAPPING_DAX_SHARED) {
+ if (folio->mapping != PAGE_MAPPING_DAX_SHARED) {
/*
* Reset the index if the page was already mapped
* regularly before.
*/
- if (page->mapping)
- page->share = 1;
- page->mapping = PAGE_MAPPING_DAX_SHARED;
+ if (folio->mapping)
+ folio->page.share = 1;
+ folio->mapping = PAGE_MAPPING_DAX_SHARED;
}
- page->share++;
+ folio->page.share++;
}
-static inline unsigned long dax_page_share_put(struct page *page)
+static inline unsigned long dax_folio_share_put(struct folio *folio)
{
- return --page->share;
+ return --folio->page.share;
}
/*
- * When it is called in dax_insert_entry(), the shared flag will indicate that
- * whether this entry is shared by multiple files. If so, set the page->mapping
- * PAGE_MAPPING_DAX_SHARED, and use page->share as refcount.
+ * When it is called in dax_insert_entry(), the shared flag will indicate
+ * that whether this entry is shared by multiple files. If so, set
+ * the folio->mapping PAGE_MAPPING_DAX_SHARED, and use page->share
+ * as refcount.
*/
static void dax_associate_entry(void *entry, struct address_space *mapping,
struct vm_area_struct *vma, unsigned long address, bool shared)
@@ -364,14 +365,14 @@ static void dax_associate_entry(void *entry, struct address_space *mapping,
index = linear_page_index(vma, address & ~(size - 1));
for_each_mapped_pfn(entry, pfn) {
- struct page *page = pfn_to_page(pfn);
+ struct folio *folio = pfn_folio(pfn);
if (shared) {
- dax_page_share_get(page);
+ dax_folio_share_get(folio);
} else {
- WARN_ON_ONCE(page->mapping);
- page->mapping = mapping;
- page->index = index + i++;
+ WARN_ON_ONCE(folio->mapping);
+ folio->mapping = mapping;
+ folio->index = index + i++;
}
}
}
@@ -385,17 +386,17 @@ static void dax_disassociate_entry(void *entry, struct address_space *mapping,
return;
for_each_mapped_pfn(entry, pfn) {
- struct page *page = pfn_to_page(pfn);
+ struct folio *folio = pfn_folio(pfn);
- WARN_ON_ONCE(trunc && page_ref_count(page) > 1);
- if (dax_page_is_shared(page)) {
+ WARN_ON_ONCE(trunc && folio_ref_count(folio) > 1);
+ if (dax_folio_is_shared(folio)) {
/* keep the shared flag if this page is still shared */
- if (dax_page_share_put(page) > 0)
+ if (dax_folio_share_put(folio) > 0)
continue;
} else
- WARN_ON_ONCE(page->mapping && page->mapping != mapping);
- page->mapping = NULL;
- page->index = 0;
+ WARN_ON_ONCE(folio->mapping && folio->mapping != mapping);
+ folio->mapping = NULL;
+ folio->index = 0;
}
}
Looks good.
Reviewed-by: Jane Chu <jane.chu@xxxxxxxxxx>
-jane
