diff mbox series

[04/21] shmem: move the shmem_mapping assert into shmem_get_folio_gfp

Message ID 20240126132903.2700077-5-hch@lst.de (mailing list archive)
State New
Headers show
Series [01/21] mm: move mapping_set_update out of <linux/swap.h> | expand

Commit Message

Christoph Hellwig Jan. 26, 2024, 1:28 p.m. UTC 
Move the check that the inode really is a shmemfs one from
shmem_read_folio_gfp to shmem_get_folio_gfp given that shmem_get_folio
can also be called from outside of shmem.c.  Also turn it into a
WARN_ON_ONCE and error return instead of BUG_ON to be less severe.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
---
 mm/shmem.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Matthew Wilcox Jan. 26, 2024, 3:09 p.m. UTC | #1 
On Fri, Jan 26, 2024 at 02:28:46PM +0100, Christoph Hellwig wrote:
> Move the check that the inode really is a shmemfs one from
> shmem_read_folio_gfp to shmem_get_folio_gfp given that shmem_get_folio
> can also be called from outside of shmem.c.  Also turn it into a
> WARN_ON_ONCE and error return instead of BUG_ON to be less severe.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Darrick J. Wong <djwong@kernel.org>

Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
diff mbox series

Patch

diff --git a/mm/shmem.c b/mm/shmem.c
index 1900916aa84d13..ad533b2f0721a7 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1972,6 +1972,9 @@  static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
 	int error;
 	bool alloced;
 
+	if (WARN_ON_ONCE(!shmem_mapping(inode->i_mapping)))
+		return -EINVAL;
+
 	if (index > (MAX_LFS_FILESIZE >> PAGE_SHIFT))
 		return -EFBIG;
 repeat:
@@ -4915,7 +4918,6 @@  struct folio *shmem_read_folio_gfp(struct address_space *mapping,
 	struct folio *folio;
 	int error;
 
-	BUG_ON(!shmem_mapping(mapping));
 	error = shmem_get_folio_gfp(inode, index, &folio, SGP_CACHE,
 				    gfp, NULL, NULL);
 	if (error)