Hi all, __filemap_get_folio and its wrappers can return NULL for three different conditions, which in some cases requires the caller to reverse engineer the decision making. This is fixed by returning an ERR_PTR instead of NULL and thus transporting the reason for the failure. But to make that work we first need to ensure that no xa_value special case is returned and thus return the FGP_ENTRY flag. It turns out that flag is barely used and can usually be deal with in a better way. Note that the shmem patches in here are non-trivial and need some careful review and testing. Changes since v1: - drop the patches to check for errors in btrfs and gfs2 - document the new calling conventions for the wrappers around __filemap_get_folio - rebased against the iomap changes in latest linux-next Diffstat fs/afs/dir.c | 10 +++---- fs/afs/dir_edit.c | 2 - fs/afs/write.c | 4 +- fs/btrfs/disk-io.c | 2 - fs/ext4/inode.c | 2 - fs/ext4/move_extent.c | 8 ++--- fs/hugetlbfs/inode.c | 2 - fs/iomap/buffered-io.c | 15 +---------- fs/netfs/buffered_read.c | 4 +- fs/nilfs2/page.c | 6 ++-- include/linux/pagemap.h | 15 +++++------ include/linux/shmem_fs.h | 1 mm/filemap.c | 27 ++++++++----------- mm/folio-compat.c | 4 +- mm/huge_memory.c | 5 +-- mm/memcontrol.c | 2 - mm/mincore.c | 2 - mm/shmem.c | 64 +++++++++++++++++++---------------------------- mm/swap_state.c | 17 ++++++------ mm/swapfile.c | 4 +- mm/truncate.c | 15 +++++------ 21 files changed, 94 insertions(+), 117 deletions(-)