From patchwork Wed Sep 30 10:45:22 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 7296681 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id ECD469F1D5 for ; Wed, 30 Sep 2015 10:56:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D8D3120645 for ; Wed, 30 Sep 2015 10:56:21 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D0DFB20644 for ; Wed, 30 Sep 2015 10:56:20 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZhF28-0003Tg-F7; Wed, 30 Sep 2015 10:54:48 +0000 Received: from smtp.citrix.com ([66.165.176.89]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZhEvK-0006XU-Ev for linux-arm-kernel@lists.infradead.org; Wed, 30 Sep 2015 10:47:48 +0000 X-IronPort-AV: E=Sophos;i="5.17,611,1437436800"; d="scan'208";a="303322862" From: Julien Grall To: Subject: [PATCH v5 07/22] block/xen-blkfront: Store a page rather a pfn in the grant structure Date: Wed, 30 Sep 2015 11:45:22 +0100 Message-ID: <1443609937-25278-8-git-send-email-julien.grall@citrix.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1443609937-25278-1-git-send-email-julien.grall@citrix.com> References: <1443609937-25278-1-git-send-email-julien.grall@citrix.com> MIME-Version: 1.0 X-DLP: MIA1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150930_034746_920729_05DC0782 X-CRM114-Status: GOOD ( 14.43 ) X-Spam-Score: -6.9 (------) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, Konrad Rzeszutek Wilk , linux-kernel@vger.kernel.org, Julien Grall , David Vrabel , Boris Ostrovsky , linux-arm-kernel@lists.infradead.org, =?UTF-8?q?Roger=20Pau=20Monn=C3=A9?= Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 Acked-by: Roger Pau Monné Reviewed-by: Stefano Stabellini --- Cc: Konrad Rzeszutek Wilk Cc: Boris Ostrovsky Cc: David Vrabel Changes in v4: - rebase after 7adf12b87f45a77d364464018fb8e9e1ac875152 "xen-blkfront: don't add indirect pages to list when !feature_persistent" Changes in v3: - Use the correct indentation in get_grant. The current indentation (i.e without this patch) was wrong because it was using space rather than tabulation. - Add Roger's acked and Stefano's reviewed - s/mfn/gfn based on the new naming Changes in v2: - Patch added --- drivers/block/xen-blkfront.c | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-) diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index c94ca26..dbd5bb6 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -68,7 +68,7 @@ enum blkif_state { struct grant { grant_ref_t gref; - unsigned long pfn; + struct page *page; struct list_head node; }; @@ -221,7 +221,7 @@ 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; @@ -236,7 +236,7 @@ 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--; } @@ -245,8 +245,8 @@ out_of_memory: } static struct grant *get_grant(grant_ref_t *gref_head, - unsigned long pfn, - struct blkfront_info *info) + struct page *page, + struct blkfront_info *info) { struct grant *gnt_list_entry; unsigned long buffer_gfn; @@ -265,10 +265,10 @@ 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_gfn = pfn_to_gfn(gnt_list_entry->pfn); + buffer_gfn = xen_page_to_gfn(gnt_list_entry->page); gnttab_grant_foreign_access_ref(gnt_list_entry->gref, info->xbdev->otherend_id, buffer_gfn, 0); @@ -524,7 +524,7 @@ 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); @@ -541,15 +541,15 @@ 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; @@ -560,7 +560,7 @@ 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)); /* @@ -1001,7 +1001,7 @@ 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); } } @@ -1036,7 +1036,7 @@ 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); } @@ -1050,7 +1050,7 @@ 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); } @@ -1101,8 +1101,7 @@ 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, * available pages for indirect grefs. */ if (!info->feature_persistent) { - 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;