Commit 81914aff authored by Hugh Dickins's avatar Hugh Dickins Committed by Andrew Morton
Browse files

shmem: shmem_get_partial_folio use filemap_get_entry 

To avoid use of the FGP_ENTRY flag, adapt shmem_get_partial_folio() to use
filemap_get_entry() and folio_lock() instead of __filemap_get_folio(). 
Update "page" in the comments there to "folio".

Link: https://lkml.kernel.org/r/9d1aaa4-1337-fb81-6f37-74ebc96f9ef@google.com


Signed-off-by: default avatarHugh Dickins <hughd@google.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 097b3e59

mm/shmem.c

+12 −5
Original line number Diff line number Diff line
@@ -885,14 +885,21 @@ static struct folio *shmem_get_partial_folio(struct inode *inode, pgoff_t index) 


	/*

	 * At first avoid shmem_get_folio(,,,SGP_READ): that fails

	 * beyond i_size, and reports fallocated pages as holes.

	 * beyond i_size, and reports fallocated folios as holes.

	 */

	folio = __filemap_get_folio(inode->i_mapping, index,

					FGP_ENTRY | FGP_LOCK, 0);

	if (!xa_is_value(folio))

	folio = filemap_get_entry(inode->i_mapping, index);

	if (!folio)

		return folio;

	if (!xa_is_value(folio)) {

		folio_lock(folio);

		if (folio->mapping == inode->i_mapping)

			return folio;

		/* The folio has been swapped out */

		folio_unlock(folio);

		folio_put(folio);

	}

	/*

	 * But read a page back from swap if any of it is within i_size

	 * But read a folio back from swap if any of it is within i_size

	 * (although in some cases this is just a waste of time).

	 */

	folio = NULL;