From nobody Fri Sep 12 09:41:50 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24F8CC04E69 for ; Thu, 10 Aug 2023 16:01:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236348AbjHJQBR (ORCPT ); Thu, 10 Aug 2023 12:01:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236300AbjHJQBD (ORCPT ); Thu, 10 Aug 2023 12:01:03 -0400 Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D65C2713; Thu, 10 Aug 2023 09:00:49 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 13F5C635D2A4; Thu, 10 Aug 2023 18:00:48 +0200 (CEST) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id bugUimCkv4m6; Thu, 10 Aug 2023 18:00:47 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 9720F635D2A2; Thu, 10 Aug 2023 18:00:47 +0200 (CEST) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id NfQzJITzRPaO; Thu, 10 Aug 2023 18:00:47 +0200 (CEST) Received: from foxxylove.corp.sigma-star.at (unknown [82.150.214.1]) by lithops.sigma-star.at (Postfix) with ESMTPSA id 386F5635D296; Thu, 10 Aug 2023 18:00:47 +0200 (CEST) From: Richard Weinberger To: linux-mtd@lists.infradead.org Cc: Christoph Hellwig , Stephan Wurm , Richard Weinberger , Miquel Raynal , Vignesh Raghavendra , Oliver Neukum , Ali Akcaagac , Jamie Lenehan , "James E.J. Bottomley" , "Martin K. Petersen" , Ezequiel Garcia , linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org Subject: [PATCH 6/7] ubi: block: Switch to kmap_sg Date: Thu, 10 Aug 2023 18:00:17 +0200 Message-Id: <20230810160019.16977-7-richard@nod.at> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20230810160019.16977-1-richard@nod.at> References: <20230810160019.16977-1-richard@nod.at> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Remove our copy of scsi_kmap_atomic_sg() and use the new helper kmap_sg(). Since it is based on kmap_local() we can remove the bounce buffer and perform IO while we hold the mapping. Signed-off-by: Richard Weinberger --- drivers/mtd/ubi/eba.c | 59 +++++-------------------------------------- 1 file changed, 6 insertions(+), 53 deletions(-) diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c index 82c54bf7c2067..650eacab27f03 100644 --- a/drivers/mtd/ubi/eba.c +++ b/drivers/mtd/ubi/eba.c @@ -731,44 +731,6 @@ int ubi_eba_read_leb(struct ubi_device *ubi, struct ub= i_volume *vol, int lnum, return err; } =20 -/* - * Basically a copy of scsi_kmap_atomic_sg(). - * As long scsi_kmap_atomic_sg() is not part of lib/scatterlist.c have - * our own version to avoid a dependency on CONFIG_SCSI. - */ -static void *ubi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count, - size_t *offset, size_t *len) -{ - int i; - size_t sg_len =3D 0, len_complete =3D 0; - struct scatterlist *sg; - struct page *page; - - for_each_sg(sgl, sg, sg_count, i) { - len_complete =3D sg_len; /* Complete sg-entries */ - sg_len +=3D sg->length; - if (sg_len > *offset) - break; - } - - if (WARN_ON_ONCE(i =3D=3D sg_count)) - return NULL; - - /* Offset starting from the beginning of first page in this sg-entry */ - *offset =3D *offset - len_complete + sg->offset; - - /* Assumption: contiguous pages can be accessed as "page + i" */ - page =3D nth_page(sg_page(sg), (*offset >> PAGE_SHIFT)); - *offset &=3D ~PAGE_MASK; - - /* Bytes in this sg-entry from *offset to the end of the page */ - sg_len =3D PAGE_SIZE - *offset; - if (*len > sg_len) - *len =3D sg_len; - - return kmap_atomic(page); -} - /** * ubi_eba_read_leb_sg - read data into a scatter gather list. * @ubi: UBI device description object @@ -789,17 +751,6 @@ int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct= ubi_volume *vol, { size_t map_len, map_offset, cur_offset; int ret, to_read =3D len; - char *bounce_buf; - - bounce_buf =3D kvmalloc(to_read, GFP_KERNEL); - if (!bounce_buf) { - ret =3D -ENOMEM; - goto out; - } - - ret =3D ubi_eba_read_leb(ubi, vol, lnum, bounce_buf, offset, to_read, che= ck); - if (ret < 0) - goto out; =20 cur_offset =3D 0; while (to_read > 0) { @@ -808,9 +759,12 @@ int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct= ubi_volume *vol, map_len =3D to_read; map_offset =3D cur_offset + sgl->tot_offset; =20 - dst =3D ubi_kmap_atomic_sg(sgl->sg, sgl->len, &map_offset, &map_len); - memcpy(dst + map_offset, bounce_buf + cur_offset, map_len); - kunmap_atomic(dst); + dst =3D kmap_sg(sgl->sg, sgl->len, &map_offset, &map_len); + ret =3D ubi_eba_read_leb(ubi, vol, lnum, dst + map_offset, offset + cur_= offset, + map_len, check); + if (ret < 0) + goto out; + kunmap_sg(dst); =20 cur_offset +=3D map_len; to_read -=3D map_len; @@ -818,7 +772,6 @@ int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct = ubi_volume *vol, =20 ret =3D 0; out: - kvfree(bounce_buf); return ret; } =20 --=20 2.35.3