[PATCH] folio: Add replacements for page_endio()

David Howells
2021-11-03T16:00:30Z

Add three functions to replace page_endio():

(1) folio_end_read(). End a read to a folio.

(2) folio_end_write(). End a write from a folio.

(3) folio_endio(). A switcher that does one or the other of the above.

Change page_endio() to just call folio_endio(). Note that the parameter
order is switched so that the folio_endio() stub doesn't have to shuffle
the params around, but can rather just test and jump.

Signed-off-by: David Howells <dhowells@redhat.com>
---
include/linux/pagemap.h | 9 ++++++
mm/filemap.c | 64 ++++++++++++++++++++++++++++++++----------------
2 files changed, 51 insertions(+), 22 deletions(-)

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index e4b98714f763..29b4ee189cb8 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -845,7 +845,14 @@ static inline int __must_check write_one_page(struct page *page)
int __set_page_dirty_nobuffers(struct page *page);
int __set_page_dirty_no_writeback(struct page *page);

-void page_endio(struct page *page, bool is_write, int err);
+void folio_end_read(struct folio *folio, int err);
+void folio_end_write(struct folio *folio, int err);
+void folio_endio(struct folio *folio, int err, bool is_write);
+
+static inline void page_endio(struct page *page, bool is_write, int err)
+{
+ folio_endio(page_folio(page), err, is_write);
+}

void folio_end_private_2(struct folio *folio);
void folio_wait_private_2(struct folio *folio);
diff --git a/mm/filemap.c b/mm/filemap.c
index bfcef6ff7a27..e4e90f96bf1c 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1596,33 +1596,55 @@ void folio_end_writeback(struct folio *folio)
}
EXPORT_SYMBOL(folio_end_writeback);

-/*
- * After completing I/O on a page, call this routine to update the page
- * flags appropriately
+/**
+ * folio_end_read - Update the state of a folio after a read
+ * @folio: The folio to update
+ * @err: The error code (or 0) to apply
*/
-void page_endio(struct page *page, bool is_write, int err)
+void folio_end_read(struct folio *folio, int err)
{
- if (!is_write) {
- if (!err) {
- SetPageUptodate(page);
- } else {
- ClearPageUptodate(page);
- SetPageError(page);
- }
- unlock_page(page);
+ if (!err) {
+ folio_mark_uptodate(folio);
} else {
- if (err) {
- struct address_space *mapping;
+ folio_clear_uptodate(folio);
+ folio_set_error(folio);
+ }
+ folio_unlock(folio);
+}
+EXPORT_SYMBOL_GPL(folio_end_read);

- SetPageError(page);
- mapping = page_mapping(page);
- if (mapping)
- mapping_set_error(mapping, err);
- }
- end_page_writeback(page);
+/**
+ * folio_end_write - Update the state of a folio after a write
+ * @folio: The folio to update
+ * @err: The error code (or 0) to apply
+ */
+void folio_end_write(struct folio *folio, int err)
+{
+ if (err) {
+ struct address_space *mapping = folio_mapping(folio);
+
+ folio_set_error(folio);
+ if (mapping)
+ mapping_set_error(mapping, err);
}
+ folio_end_writeback(folio);
+}
+EXPORT_SYMBOL_GPL(folio_end_write);
+
+/**
+ * folio_endio - Update the state of a folio after a read or write
+ * @folio: The folio to update
+ * @err: The error code (or 0) to apply
+ * @is_write: True if this was a write
+ */
+void folio_endio(struct folio *folio, int err, bool is_write)
+{
+ if (is_write)
+ folio_end_write(folio, err);
+ else
+ folio_end_read(folio, err);
}
-EXPORT_SYMBOL_GPL(page_endio);
+EXPORT_SYMBOL_GPL(folio_endio);

/**
* __folio_lock - Get a lock on the folio, assuming we need to sleep to get it.