squashfs: pass the inode to squashfs_readahead_fragment()

Patch series "squashfs: Remove page->mapping references".

We're close to being able to kill page->mapping.  These two patches get us
a little bit closer.


This patch (of 2):

Eliminate a reference to page->mapping by passing the inode from the
caller.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Cc: Phillip Lougher <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: Matthew Wilcox (Oracle)

fs/squashfs/file.c

@@ -493,10 +493,9 @@ static int squashfs_read_folio(struct file *file, struct folio *folio)
 	return res;
 }
 
-static int squashfs_readahead_fragment(struct page **page,
+static int squashfs_readahead_fragment(struct inode *inode, struct page **page,
 	unsigned int pages, unsigned int expected, loff_t start)
 {
-	struct inode *inode = page[0]->mapping->host;
 	struct squashfs_cache_entry *buffer = squashfs_get_fragment(inode->i_sb,
 		squashfs_i(inode)->fragment_block,
 		squashfs_i(inode)->fragment_size);
@@ -605,8 +604,8 @@ static void squashfs_readahead(struct readahead_control *ractl)
 
 		if (start >> msblk->block_log == file_end &&
 				squashfs_i(inode)->fragment_block != SQUASHFS_INVALID_BLK) {
-			res = squashfs_readahead_fragment(pages, nr_pages,
-							  expected, start);
+			res = squashfs_readahead_fragment(inode, pages,
+					nr_pages, expected, start);
 			if (res)
 				goto skip_pages;
 			continue;