[OLK-5.10] "939325bbad27dc filemap: Correct the conditions for marking a folio as accessed"补丁回合错误

在OLK-5.10里有个补丁 "939325bbad27dc filemap: Correct the conditions for marking a folio as  accessed"好像回合错了. 这是一个从上游合的补丁，上游补丁commit "5ccc944dce3df5f", 原始补丁如下：
```diff
+++ b/mm/filemap.c
@@ -2629,6 +2629,13 @@ static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter,
        return err;
 }
 
+static inline bool pos_same_folio(loff_t pos1, loff_t pos2, struct folio *folio)
+{
+       unsigned int shift = folio_shift(folio);
+
+       return (pos1 >> shift == pos2 >> shift);
+}
+
 /**
  * filemap_read - Read data from the page cache.
  * @iocb: The iocb to read.
@@ -2700,11 +2707,11 @@ ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *iter,
                writably_mapped = mapping_writably_mapped(mapping);
 
                /*
-                * When a sequential read accesses a page several times, only
+                * When a read accesses the same folio several times, only
                 * mark it as accessed the first time.
                 */
-               if (iocb->ki_pos >> PAGE_SHIFT !=
-                   ra->prev_pos >> PAGE_SHIFT)
+               if (!pos_same_folio(iocb->ki_pos, ra->prev_pos - 1,
+                                                       fbatch.folios[0]))
                        folio_mark_accessed(fbatch.folios[0]);
 
                for (i = 0; i < folio_batch_count(&fbatch); i++) {

```
但是欧拉回合的补丁里在` if (!pos_same_folio(iocb->ki_pos, ra->prev_pos - 1,`这一行少了一个`!`号，欧拉回合的补丁如下：
```diff
+++ b/mm/filemap.c
@@ -2437,6 +2437,13 @@ static int generic_file_buffered_read_get_pages(struct kiocb *iocb,
 	goto find_page;
 }
 
+static inline bool pos_same_page(loff_t pos1, loff_t pos2, struct page *page)
+{
+	unsigned int shift = page_shift(page);
+
+	return (pos1 >> shift == pos2 >> shift);
+}
+
 /**
  * generic_file_buffered_read - generic file read routine
  * @iocb:	the iocb to read
@@ -2527,11 +2534,10 @@ ssize_t generic_file_buffered_read(struct kiocb *iocb,
 		writably_mapped = mapping_writably_mapped(mapping);
 
 		/*
-		 * When a sequential read accesses a page several times, only
+		 * When a read accesses a page several times, only
 		 * mark it as accessed the first time.
 		 */
-		if (iocb->ki_pos >> PAGE_SHIFT !=
-		    ra->prev_pos >> PAGE_SHIFT)
+		if (pos_same_page(iocb->ki_pos, ra->prev_pos -1, pages[0]))
 			mark_page_accessed(pages[0]);
 		for (i = 1; i < pg_nr; i++)
 			mark_page_accessed(pages[i]);
-- 
```

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