Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753500AbbGPPOT (ORCPT ); Thu, 16 Jul 2015 11:14:19 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:21811 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751525AbbGPPOS (ORCPT ); Thu, 16 Jul 2015 11:14:18 -0400 X-IronPort-AV: E=Sophos;i="5.15,488,1432598400"; d="scan'208";a="284754474" Date: Thu, 16 Jul 2015 16:11:40 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Julien Grall CC: , , , , , Konrad Rzeszutek Wilk , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= , Boris Ostrovsky , "David Vrabel" Subject: Re: [PATCH v2 06/20] block/xen-blkfront: Store a page rather a pfn in the grant structure In-Reply-To: <1436474552-31789-7-git-send-email-julien.grall@citrix.com> Message-ID: References: <1436474552-31789-1-git-send-email-julien.grall@citrix.com> <1436474552-31789-7-git-send-email-julien.grall@citrix.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="1342847746-382286837-1437059512=:17378" X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6729 Lines: 178 --1342847746-382286837-1437059512=:17378 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT On Thu, 9 Jul 2015, Julien Grall wrote: > All the usage of the field pfn are done using the same idiom: > > pfn_to_page(grant->pfn) > > This will return always the same page. Store directly the page in the > grant to clean up the code. > > Signed-off-by: Julien Grall > Cc: Konrad Rzeszutek Wilk > Cc: Roger Pau Monné > Cc: Boris Ostrovsky > Cc: David Vrabel > --- > Changes in v2: > - Patch added > --- > drivers/block/xen-blkfront.c | 37 ++++++++++++++++++------------------- > 1 file changed, 18 insertions(+), 19 deletions(-) > > diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c > index 7107d58..7b81d23 100644 > --- a/drivers/block/xen-blkfront.c > +++ b/drivers/block/xen-blkfront.c > @@ -67,7 +67,7 @@ enum blkif_state { > > struct grant { > grant_ref_t gref; > - unsigned long pfn; > + struct page *page; > struct list_head node; > }; > > @@ -219,7 +219,7 @@ static int fill_grant_buffer(struct blkfront_info *info, int num) > kfree(gnt_list_entry); > goto out_of_memory; > } > - gnt_list_entry->pfn = page_to_pfn(granted_page); > + gnt_list_entry->page = granted_page; > } > > gnt_list_entry->gref = GRANT_INVALID_REF; > @@ -234,7 +234,7 @@ out_of_memory: > &info->grants, node) { > list_del(&gnt_list_entry->node); > if (info->feature_persistent) > - __free_page(pfn_to_page(gnt_list_entry->pfn)); > + __free_page(gnt_list_entry->page); > kfree(gnt_list_entry); > i--; > } > @@ -243,7 +243,7 @@ out_of_memory: > } > > static struct grant *get_grant(grant_ref_t *gref_head, > - unsigned long pfn, > + struct page *page, > struct blkfront_info *info) indentation Aside from this: Reviewed-by: Stefano Stabellini > { > struct grant *gnt_list_entry; > @@ -263,10 +263,10 @@ static struct grant *get_grant(grant_ref_t *gref_head, > gnt_list_entry->gref = gnttab_claim_grant_reference(gref_head); > BUG_ON(gnt_list_entry->gref == -ENOSPC); > if (!info->feature_persistent) { > - BUG_ON(!pfn); > - gnt_list_entry->pfn = pfn; > + BUG_ON(!page); > + gnt_list_entry->page = page; > } > - buffer_mfn = pfn_to_mfn(gnt_list_entry->pfn); > + buffer_mfn = page_to_mfn(gnt_list_entry->page); > gnttab_grant_foreign_access_ref(gnt_list_entry->gref, > info->xbdev->otherend_id, > buffer_mfn, 0); > @@ -522,7 +522,7 @@ static int blkif_queue_rw_req(struct request *req) > > if ((ring_req->operation == BLKIF_OP_INDIRECT) && > (i % SEGS_PER_INDIRECT_FRAME == 0)) { > - unsigned long uninitialized_var(pfn); > + struct page *uninitialized_var(page); > > if (segments) > kunmap_atomic(segments); > @@ -536,15 +536,15 @@ static int blkif_queue_rw_req(struct request *req) > indirect_page = list_first_entry(&info->indirect_pages, > struct page, lru); > list_del(&indirect_page->lru); > - pfn = page_to_pfn(indirect_page); > + page = indirect_page; > } > - gnt_list_entry = get_grant(&gref_head, pfn, info); > + gnt_list_entry = get_grant(&gref_head, page, info); > info->shadow[id].indirect_grants[n] = gnt_list_entry; > - segments = kmap_atomic(pfn_to_page(gnt_list_entry->pfn)); > + segments = kmap_atomic(gnt_list_entry->page); > ring_req->u.indirect.indirect_grefs[n] = gnt_list_entry->gref; > } > > - gnt_list_entry = get_grant(&gref_head, page_to_pfn(sg_page(sg)), info); > + gnt_list_entry = get_grant(&gref_head, sg_page(sg), info); > ref = gnt_list_entry->gref; > > info->shadow[id].grants_used[i] = gnt_list_entry; > @@ -555,7 +555,7 @@ static int blkif_queue_rw_req(struct request *req) > > BUG_ON(sg->offset + sg->length > PAGE_SIZE); > > - shared_data = kmap_atomic(pfn_to_page(gnt_list_entry->pfn)); > + shared_data = kmap_atomic(gnt_list_entry->page); > bvec_data = kmap_atomic(sg_page(sg)); > > /* > @@ -1002,7 +1002,7 @@ static void blkif_free(struct blkfront_info *info, int suspend) > info->persistent_gnts_c--; > } > if (info->feature_persistent) > - __free_page(pfn_to_page(persistent_gnt->pfn)); > + __free_page(persistent_gnt->page); > kfree(persistent_gnt); > } > } > @@ -1037,7 +1037,7 @@ static void blkif_free(struct blkfront_info *info, int suspend) > persistent_gnt = info->shadow[i].grants_used[j]; > gnttab_end_foreign_access(persistent_gnt->gref, 0, 0UL); > if (info->feature_persistent) > - __free_page(pfn_to_page(persistent_gnt->pfn)); > + __free_page(persistent_gnt->page); > kfree(persistent_gnt); > } > > @@ -1051,7 +1051,7 @@ static void blkif_free(struct blkfront_info *info, int suspend) > for (j = 0; j < INDIRECT_GREFS(segs); j++) { > persistent_gnt = info->shadow[i].indirect_grants[j]; > gnttab_end_foreign_access(persistent_gnt->gref, 0, 0UL); > - __free_page(pfn_to_page(persistent_gnt->pfn)); > + __free_page(persistent_gnt->page); > kfree(persistent_gnt); > } > > @@ -1102,8 +1102,7 @@ static void blkif_completion(struct blk_shadow *s, struct blkfront_info *info, > if (bret->operation == BLKIF_OP_READ && info->feature_persistent) { > for_each_sg(s->sg, sg, nseg, i) { > BUG_ON(sg->offset + sg->length > PAGE_SIZE); > - shared_data = kmap_atomic( > - pfn_to_page(s->grants_used[i]->pfn)); > + shared_data = kmap_atomic(s->grants_used[i]->page); > bvec_data = kmap_atomic(sg_page(sg)); > memcpy(bvec_data + sg->offset, > shared_data + sg->offset, > @@ -1154,7 +1153,7 @@ static void blkif_completion(struct blk_shadow *s, struct blkfront_info *info, > * Add the used indirect page back to the list of > * available pages for indirect grefs. > */ > - indirect_page = pfn_to_page(s->indirect_grants[i]->pfn); > + indirect_page = s->indirect_grants[i]->page; > list_add(&indirect_page->lru, &info->indirect_pages); > s->indirect_grants[i]->gref = GRANT_INVALID_REF; > list_add_tail(&s->indirect_grants[i]->node, &info->grants); > -- > 2.1.4 > --1342847746-382286837-1437059512=:17378-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/