From a7a6df222351de23791bb64165f14c21ff4d1653 Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Tue, 30 Jun 2015 11:58:51 +0100 Subject: [PATCH] block/xen-blkfront: Store a page rather a pfn in the grant structure MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: David Vrabel --- 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 bf9ccfe03f45..7552ca8f8ffe 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; -- 2.20.1