The quilt patch titled
Subject: shmem: convert shmem_write_end() to use a folio
has been removed from the -mm tree. Its filename was
shmem-convert-shmem_write_end-to-use-a-folio.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: shmem: convert shmem_write_end() to use a folio
Date: Thu, 12 Jan 2023 13:10:31 +0000
Use a folio internally to shmem_write_end() which saves a number of calls
to compound_head() and lets us get rid of the custom code to zero out the
rest of a THP and supports folios of arbitrary size.
Link: https://lkml.kernel.org/r/20230112131031.1209553-1-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: William Kucharski <william.kucharski@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/mm/shmem.c~shmem-convert-shmem_write_end-to-use-a-folio
+++ a/mm/shmem.c
@@ -2578,33 +2578,23 @@ shmem_write_end(struct file *file, struc
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata)
{
+ struct folio *folio = page_folio(page);
struct inode *inode = mapping->host;
if (pos + copied > inode->i_size)
i_size_write(inode, pos + copied);
- if (!PageUptodate(page)) {
- struct page *head = compound_head(page);
- if (PageTransCompound(page)) {
- int i;
-
- for (i = 0; i < HPAGE_PMD_NR; i++) {
- if (head + i == page)
- continue;
- clear_highpage(head + i);
- flush_dcache_page(head + i);
- }
- }
- if (copied < PAGE_SIZE) {
- unsigned from = pos & (PAGE_SIZE - 1);
- zero_user_segments(page, 0, from,
- from + copied, PAGE_SIZE);
+ if (!folio_test_uptodate(folio)) {
+ if (copied < folio_size(folio)) {
+ size_t from = offset_in_folio(folio, pos);
+ folio_zero_segments(folio, 0, from,
+ from + copied, folio_size(folio));
}
- SetPageUptodate(head);
+ folio_mark_uptodate(folio);
}
- set_page_dirty(page);
- unlock_page(page);
- put_page(page);
+ folio_mark_dirty(folio);
+ folio_unlock(folio);
+ folio_put(folio);
return copied;
}
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
