From nobody Wed May 15 18:38:16 2024 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 6D48FC433F5 for ; Tue, 24 May 2022 12:41:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235468AbiEXMlq (ORCPT ); Tue, 24 May 2022 08:41:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39950 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230250AbiEXMlm (ORCPT ); Tue, 24 May 2022 08:41:42 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA9F52EA03; Tue, 24 May 2022 05:41:40 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 638751F91B; Tue, 24 May 2022 12:41:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1653396099; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=Nq8e6f4kvt4191MArCN5QGRmiKuJD49xJ37K0fCPnN8=; b=mr4YLtsg9QoC4R9USdVqdIMnC8BnrPfzLohdM5yiGV7fDP2brJD9ab0LBDZLqW/4pe6Tct heXdZ4mhGSPCvH/D7UBEHaZYl9W5VEg67tRVFPWkl2rLNysqvxrTJ8K7EIkZWPj2aL8WSU mcItI6WDNehrbAlw08k94g4b/Y9u/R4= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id D158713AE3; Tue, 24 May 2022 12:41:38 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id STa9MYLSjGIsYQAAMHmgww (envelope-from ); Tue, 24 May 2022 12:41:38 +0000 From: Juergen Gross To: xen-devel@lists.xenproject.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, netdev@vger.kernel.org, v9fs-developer@lists.sourceforge.net Cc: Juergen Gross , Boris Ostrovsky , Stefano Stabellini , =?UTF-8?q?Roger=20Pau=20Monn=C3=A9?= , Jens Axboe , Dmitry Torokhov , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Eric Van Hensbergen , Latchesar Ionkov , Dominique Martinet , Christian Schoenebeck , Jan Beulich Subject: [PATCH] xen: switch gnttab_end_foreign_access() to take a struct page pointer Date: Tue, 24 May 2022 14:41:37 +0200 Message-Id: <20220524124137.10021-1-jgross@suse.com> X-Mailer: git-send-email 2.35.3 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" Instead of a virtual kernel address use a pointer of the associated struct page as second parameter of gnttab_end_foreign_access(). Most users have that pointer available already and are creating the virtual address from it, risking problems in case the memory is located in highmem. gnttab_end_foreign_access() itself won't need to get the struct page from the address again. Suggested-by: Jan Beulich Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich --- drivers/block/xen-blkfront.c | 6 +++--- drivers/input/misc/xen-kbdfront.c | 4 ++-- drivers/net/xen-netfront.c | 7 +++---- drivers/xen/gntalloc.c | 9 +++------ drivers/xen/gntdev-dmabuf.c | 2 +- drivers/xen/grant-table.c | 8 ++++---- drivers/xen/pvcalls-front.c | 6 +++--- drivers/xen/xen-front-pgdir-shbuf.c | 2 +- drivers/xen/xenbus/xenbus_client.c | 2 +- include/xen/grant_table.h | 6 +++--- net/9p/trans_xen.c | 8 ++++---- 11 files changed, 28 insertions(+), 32 deletions(-) diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 55e004d03ced..a88ce4426400 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -1221,7 +1221,7 @@ static void blkif_free_ring(struct blkfront_ring_info= *rinfo) list_del(&persistent_gnt->node); if (persistent_gnt->gref !=3D INVALID_GRANT_REF) { gnttab_end_foreign_access(persistent_gnt->gref, - 0UL); + NULL); rinfo->persistent_gnts_c--; } if (info->feature_persistent) @@ -1244,7 +1244,7 @@ static void blkif_free_ring(struct blkfront_ring_info= *rinfo) rinfo->shadow[i].req.u.rw.nr_segments; for (j =3D 0; j < segs; j++) { persistent_gnt =3D rinfo->shadow[i].grants_used[j]; - gnttab_end_foreign_access(persistent_gnt->gref, 0UL); + gnttab_end_foreign_access(persistent_gnt->gref, NULL); if (info->feature_persistent) __free_page(persistent_gnt->page); kfree(persistent_gnt); @@ -1259,7 +1259,7 @@ static void blkif_free_ring(struct blkfront_ring_info= *rinfo) =20 for (j =3D 0; j < INDIRECT_GREFS(segs); j++) { persistent_gnt =3D rinfo->shadow[i].indirect_grants[j]; - gnttab_end_foreign_access(persistent_gnt->gref, 0UL); + gnttab_end_foreign_access(persistent_gnt->gref, NULL); __free_page(persistent_gnt->page); kfree(persistent_gnt); } diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbd= front.c index 1fc9b3e7007f..8d8ebdc2039b 100644 --- a/drivers/input/misc/xen-kbdfront.c +++ b/drivers/input/misc/xen-kbdfront.c @@ -481,7 +481,7 @@ static int xenkbd_connect_backend(struct xenbus_device = *dev, error_evtchan: xenbus_free_evtchn(dev, evtchn); error_grant: - gnttab_end_foreign_access(info->gref, 0UL); + gnttab_end_foreign_access(info->gref, NULL); info->gref =3D -1; return ret; } @@ -492,7 +492,7 @@ static void xenkbd_disconnect_backend(struct xenkbd_inf= o *info) unbind_from_irqhandler(info->irq, info); info->irq =3D -1; if (info->gref >=3D 0) - gnttab_end_foreign_access(info->gref, 0UL); + gnttab_end_foreign_access(info->gref, NULL); info->gref =3D -1; } =20 diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 65ab907aca5a..8c0b9546d5a2 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1386,7 +1386,7 @@ static void xennet_release_tx_bufs(struct netfront_qu= eue *queue) queue->tx_skbs[i] =3D NULL; get_page(queue->grant_tx_page[i]); gnttab_end_foreign_access(queue->grant_tx_ref[i], - (unsigned long)page_address(queue->grant_tx_page[i])); + queue->grant_tx_page[i]); queue->grant_tx_page[i] =3D NULL; queue->grant_tx_ref[i] =3D INVALID_GRANT_REF; add_id_to_list(&queue->tx_skb_freelist, queue->tx_link, i); @@ -1418,8 +1418,7 @@ static void xennet_release_rx_bufs(struct netfront_qu= eue *queue) * foreign access is ended (which may be deferred). */ get_page(page); - gnttab_end_foreign_access(ref, - (unsigned long)page_address(page)); + gnttab_end_foreign_access(ref, page); queue->grant_rx_ref[id] =3D INVALID_GRANT_REF; =20 kfree_skb(skb); @@ -1760,7 +1759,7 @@ static void xennet_end_access(int ref, void *page) { /* This frees the page as a side-effect */ if (ref !=3D INVALID_GRANT_REF) - gnttab_end_foreign_access(ref, (unsigned long)page); + gnttab_end_foreign_access(ref, virt_to_page(page)); } =20 static void xennet_disconnect_backend(struct netfront_info *info) diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c index 55acb32842a3..a15729beb9d1 100644 --- a/drivers/xen/gntalloc.c +++ b/drivers/xen/gntalloc.c @@ -175,8 +175,6 @@ static int add_grefs(struct ioctl_gntalloc_alloc_gref *= op, =20 static void __del_gref(struct gntalloc_gref *gref) { - unsigned long addr; - if (gref->notify.flags & UNMAP_NOTIFY_CLEAR_BYTE) { uint8_t *tmp =3D kmap_local_page(gref->page); tmp[gref->notify.pgoff] =3D 0; @@ -190,10 +188,9 @@ static void __del_gref(struct gntalloc_gref *gref) gref->notify.flags =3D 0; =20 if (gref->gref_id) { - if (gref->page) { - addr =3D (unsigned long)page_to_virt(gref->page); - gnttab_end_foreign_access(gref->gref_id, addr); - } else + if (gref->page) + gnttab_end_foreign_access(gref->gref_id, gref->page); + else gnttab_free_grant_reference(gref->gref_id); } =20 diff --git a/drivers/xen/gntdev-dmabuf.c b/drivers/xen/gntdev-dmabuf.c index 91073b4e4a20..940e5e9e8a54 100644 --- a/drivers/xen/gntdev-dmabuf.c +++ b/drivers/xen/gntdev-dmabuf.c @@ -524,7 +524,7 @@ static void dmabuf_imp_end_foreign_access(u32 *refs, in= t count) =20 for (i =3D 0; i < count; i++) if (refs[i] !=3D INVALID_GRANT_REF) - gnttab_end_foreign_access(refs[i], 0UL); + gnttab_end_foreign_access(refs[i], NULL); } =20 static void dmabuf_imp_free_storage(struct gntdev_dmabuf *gntdev_dmabuf) diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 1a1aec0a88a1..1b9b28bc3228 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -430,13 +430,13 @@ int gnttab_try_end_foreign_access(grant_ref_t ref) } EXPORT_SYMBOL_GPL(gnttab_try_end_foreign_access); =20 -void gnttab_end_foreign_access(grant_ref_t ref, unsigned long page) +void gnttab_end_foreign_access(grant_ref_t ref, struct page *page) { if (gnttab_try_end_foreign_access(ref)) { - if (page !=3D 0) - put_page(virt_to_page(page)); + if (page) + put_page(page); } else - gnttab_add_deferred(ref, page ? virt_to_page(page) : NULL); + gnttab_add_deferred(ref, page); } EXPORT_SYMBOL_GPL(gnttab_end_foreign_access); =20 diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index e254ed19488f..1826e8e67125 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -238,8 +238,8 @@ static void pvcalls_front_free_map(struct pvcalls_bedat= a *bedata, spin_unlock(&bedata->socket_lock); =20 for (i =3D 0; i < (1 << PVCALLS_RING_ORDER); i++) - gnttab_end_foreign_access(map->active.ring->ref[i], 0); - gnttab_end_foreign_access(map->active.ref, 0); + gnttab_end_foreign_access(map->active.ring->ref[i], NULL); + gnttab_end_foreign_access(map->active.ref, NULL); free_page((unsigned long)map->active.ring); =20 kfree(map); @@ -1117,7 +1117,7 @@ static int pvcalls_front_remove(struct xenbus_device = *dev) } } if (bedata->ref !=3D -1) - gnttab_end_foreign_access(bedata->ref, 0); + gnttab_end_foreign_access(bedata->ref, NULL); kfree(bedata->ring.sring); kfree(bedata); xenbus_switch_state(dev, XenbusStateClosed); diff --git a/drivers/xen/xen-front-pgdir-shbuf.c b/drivers/xen/xen-front-pg= dir-shbuf.c index b6433761d42c..bef8d72a6ca6 100644 --- a/drivers/xen/xen-front-pgdir-shbuf.c +++ b/drivers/xen/xen-front-pgdir-shbuf.c @@ -135,7 +135,7 @@ void xen_front_pgdir_shbuf_free(struct xen_front_pgdir_= shbuf *buf) =20 for (i =3D 0; i < buf->num_grefs; i++) if (buf->grefs[i] !=3D INVALID_GRANT_REF) - gnttab_end_foreign_access(buf->grefs[i], 0UL); + gnttab_end_foreign_access(buf->grefs[i], NULL); } kfree(buf->grefs); kfree(buf->directory); diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus= _client.c index d6fdd2d209d3..d5f3f763717e 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -439,7 +439,7 @@ void xenbus_teardown_ring(void **vaddr, unsigned int nr= _pages, =20 for (i =3D 0; i < nr_pages; i++) { if (grefs[i] !=3D INVALID_GRANT_REF) { - gnttab_end_foreign_access(grefs[i], 0); + gnttab_end_foreign_access(grefs[i], NULL); grefs[i] =3D INVALID_GRANT_REF; } } diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index 7d0f2f0037b8..527c9907f99c 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -101,10 +101,10 @@ int gnttab_end_foreign_access_ref(grant_ref_t ref); * Eventually end access through the given grant reference, and once that * access has been ended, free the given page too. Access will be ended * immediately iff the grant entry is not in use, otherwise it will happen - * some time later. page may be 0, in which case no freeing will occur. + * some time later. page may be NULL, in which case no freeing will occur. * Note that the granted page might still be accessed (read or write) by t= he * other side after gnttab_end_foreign_access() returns, so even if page w= as - * specified as 0 it is not allowed to just reuse the page for other + * specified as NULL it is not allowed to just reuse the page for other * purposes immediately. gnttab_end_foreign_access() will take an addition= al * reference to the granted page in this case, which is dropped only after * the grant is no longer in use. @@ -112,7 +112,7 @@ int gnttab_end_foreign_access_ref(grant_ref_t ref); * gnttab_end_foreign_access() are done via alloc_pages_exact() (and freei= ng * via free_pages_exact()) in order to avoid high order pages. */ -void gnttab_end_foreign_access(grant_ref_t ref, unsigned long page); +void gnttab_end_foreign_access(grant_ref_t ref, struct page *page); =20 /* * End access through the given grant reference, iff the grant entry is diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c index 77883b6788cd..833cd3792c51 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -279,13 +279,13 @@ static void xen_9pfs_front_free(struct xen_9pfs_front= _priv *priv) grant_ref_t ref; =20 ref =3D priv->rings[i].intf->ref[j]; - gnttab_end_foreign_access(ref, 0); + gnttab_end_foreign_access(ref, NULL); } free_pages_exact(priv->rings[i].data.in, 1UL << (priv->rings[i].intf->ring_order + XEN_PAGE_SHIFT)); } - gnttab_end_foreign_access(priv->rings[i].ref, 0); + gnttab_end_foreign_access(priv->rings[i].ref, NULL); free_page((unsigned long)priv->rings[i].intf); } kfree(priv->rings); @@ -353,10 +353,10 @@ static int xen_9pfs_front_alloc_dataring(struct xenbu= s_device *dev, out: if (bytes) { for (i--; i >=3D 0; i--) - gnttab_end_foreign_access(ring->intf->ref[i], 0); + gnttab_end_foreign_access(ring->intf->ref[i], NULL); free_pages_exact(bytes, 1UL << (order + XEN_PAGE_SHIFT)); } - gnttab_end_foreign_access(ring->ref, 0); + gnttab_end_foreign_access(ring->ref, NULL); free_page((unsigned long)ring->intf); return ret; } --=20 2.35.3