diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 68f905713eb7..937eac50ef2e 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -461,6 +461,33 @@ bool iomap_is_partially_uptodate(struct folio *folio, size_t from, size_t count) } EXPORT_SYMBOL_GPL(iomap_is_partially_uptodate); +/** + * iomap_get_folio - get a folio reference for writing + * @iter: iteration structure + * @pos: start offset of write + * + * Returns a locked reference to the folio at @pos, or an error pointer if the + * folio could not be obtained. + */ +struct folio *iomap_get_folio(struct iomap_iter *iter, loff_t pos) +{ + unsigned fgp = FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE | FGP_NOFS; + struct folio *folio; + + if (iter->flags & IOMAP_NOWAIT) + fgp |= FGP_NOWAIT; + + folio = __filemap_get_folio(iter->inode->i_mapping, pos >> PAGE_SHIFT, + fgp, mapping_gfp_mask(iter->inode->i_mapping)); + if (folio) + return folio; + + if (iter->flags & IOMAP_NOWAIT) + return ERR_PTR(-EAGAIN); + return ERR_PTR(-ENOMEM); +} +EXPORT_SYMBOL_GPL(iomap_get_folio); + bool iomap_release_folio(struct folio *folio, gfp_t gfp_flags) { trace_iomap_release_folio(folio->mapping->host, folio_pos(folio), @@ -602,12 +629,8 @@ static int iomap_write_begin(struct iomap_iter *iter, loff_t pos, const struct iomap_page_ops *page_ops = iter->iomap.page_ops; const struct iomap *srcmap = iomap_iter_srcmap(iter); struct folio *folio; - unsigned fgp = FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE | FGP_NOFS; int status = 0; - if (iter->flags & IOMAP_NOWAIT) - fgp |= FGP_NOWAIT; - BUG_ON(pos + len > iter->iomap.offset + iter->iomap.length); if (srcmap != &iter->iomap) BUG_ON(pos + len > srcmap->offset + srcmap->length); @@ -624,12 +647,10 @@ static int iomap_write_begin(struct iomap_iter *iter, loff_t pos, return status; } - folio = __filemap_get_folio(iter->inode->i_mapping, pos >> PAGE_SHIFT, - fgp, mapping_gfp_mask(iter->inode->i_mapping)); - if (!folio) { - status = (iter->flags & IOMAP_NOWAIT) ? -EAGAIN : -ENOMEM; + folio = iomap_get_folio(iter, pos); + if (IS_ERR(folio)) { __iomap_put_folio(iter, pos, 0, NULL); - return status; + return PTR_ERR(folio); } /* diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 321edf45ad02..d45903b8fe91 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -264,6 +264,7 @@ int iomap_file_buffered_write_punch_delalloc(struct inode *inode, void iomap_readahead(struct readahead_control *, const struct iomap_ops *ops); bool iomap_is_partially_uptodate(struct folio *, size_t from, size_t count); +struct folio *iomap_get_folio(struct iomap_iter *iter, loff_t pos); bool iomap_release_folio(struct folio *folio, gfp_t gfp_flags); void iomap_invalidate_folio(struct folio *folio, size_t offset, size_t len); int iomap_file_unshare(struct inode *inode, loff_t pos, loff_t len,