From: Jens Axboe <axboe@kernel.dk> mainline inclusion from mainline-v6.10-rc2 commit b2cd5ae693a3dc5b70a0f75fba96452c591a2047 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/ICPOEB CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Add iomap buffered write support for RWF_DONTCACHE. If RWF_DONTCACHE is set for a write, mark the folios being written as uncached. Then writeback completion will drop the pages. The write_iter handler simply kicks off writeback for the pages, and writeback completion will take care of the rest. Signed-off-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20250204184047.356762-2-axboe@kernel.dk Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org> Conflicts: Documentation/filesystems/iomap/design.rst Documentation/filesystems/iomap/operations.rst include/linux/iomap.h Signed-off-by: Long Li <leo.lilong@huawei.com> --- fs/iomap/buffered-io.c | 4 ++++ include/linux/iomap.h | 1 + 2 files changed, 5 insertions(+) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index ad442f71c000..3a3f82966fbf 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -654,6 +654,8 @@ struct folio *iomap_get_folio(struct iomap_iter *iter, loff_t pos, size_t len) if (iter->flags & IOMAP_NOWAIT) fgp |= FGP_NOWAIT; + if (iter->flags & IOMAP_DONTCACHE) + fgp |= FGP_DONTCACHE; fgp |= fgf_set_order(len); return __filemap_get_folio(iter->inode->i_mapping, pos >> PAGE_SHIFT, @@ -1101,6 +1103,8 @@ iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *i, if (iocb->ki_flags & IOCB_NOWAIT) iter.flags |= IOMAP_NOWAIT; + if (iocb->ki_flags & IOCB_DONTCACHE) + iter.flags |= IOMAP_DONTCACHE; while ((ret = iomap_iter(&iter, ops)) > 0) iter.processed = iomap_write_iter(&iter, i); diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 6bd7ed98cf1f..05d68152edb3 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -178,6 +178,7 @@ struct iomap_folio_ops { #else #define IOMAP_DAX 0 #endif /* CONFIG_FS_DAX */ +#define IOMAP_DONTCACHE (1 << 10) struct iomap_ops { /* -- 2.39.2