1 files changed, 136 insertions, 45 deletions

diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index 14e452896d04..a7c2b04ab943 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -239,9 +239,9 @@ static void put_persistent_gnt(struct xen_blkif_ring *ring,
 	atomic_dec(&ring->persistent_gnt_in_use);
 }
 
-static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *root,
-                                 unsigned int num)
+static void free_persistent_gnts(struct xen_blkif_ring *ring)
 {
+	struct rb_root *root = &ring->persistent_gnts;
 	struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST];
 	struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST];
 	struct persistent_gnt *persistent_gnt;
@@ -249,6 +249,9 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro
 	int segs_to_unmap = 0;
 	struct gntab_unmap_queue_data unmap_data;
 
+	if (RB_EMPTY_ROOT(root))
+		return;
+
 	unmap_data.pages = pages;
 	unmap_data.unmap_ops = unmap;
 	unmap_data.kunmap_ops = NULL;
@@ -277,9 +280,11 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro
 
 		rb_erase(&persistent_gnt->node, root);
 		kfree(persistent_gnt);
-		num--;
+		ring->persistent_gnt_c--;
 	}
-	BUG_ON(num != 0);
+
+	BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts));
+	BUG_ON(ring->persistent_gnt_c != 0);
 }
 
 void xen_blkbk_unmap_purged_grants(struct work_struct *work)
@@ -442,7 +447,7 @@ static void free_req(struct xen_blkif_ring *ring, struct pending_req *req)
  * Routines for managing virtual block devices (vbds).
  */
 static int xen_vbd_translate(struct phys_req *req, struct xen_blkif *blkif,
-			     int operation)
+			     enum req_op operation)
 {
 	struct xen_vbd *vbd = &blkif->vbd;
 	int rc = -EACCES;
@@ -460,7 +465,7 @@ static int xen_vbd_translate(struct phys_req *req, struct xen_blkif *blkif,
 	}
 
 	req->dev  = vbd->pdevice;
-	req->bdev = vbd->bdev;
+	req->bdev = file_bdev(vbd->bdev_file);
 	rc = 0;
 
  out:
@@ -539,7 +544,7 @@ static void print_stats(struct xen_blkif_ring *ring)
 		 ring->st_rd_req, ring->st_wr_req,
 		 ring->st_f_req, ring->st_ds_req,
 		 ring->persistent_gnt_c, max_pgrants);
-	ring->st_print = jiffies + msecs_to_jiffies(10 * 1000);
+	ring->st_print = jiffies + secs_to_jiffies(10);
 	ring->st_rd_req = 0;
 	ring->st_wr_req = 0;
 	ring->st_oo_req = 0;
@@ -631,12 +636,7 @@ purge_gnt_list:
 void xen_blkbk_free_caches(struct xen_blkif_ring *ring)
 {
 	/* Free all persistent grant pages */
-	if (!RB_EMPTY_ROOT(&ring->persistent_gnts))
-		free_persistent_gnts(ring, &ring->persistent_gnts,
-			ring->persistent_gnt_c);
-
-	BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts));
-	ring->persistent_gnt_c = 0;
+	free_persistent_gnts(ring);
 
 	/* Since we are shutting down remove all pages from the buffer */
 	gnttab_page_cache_shrink(&ring->free_pages, 0 /* All */);
@@ -891,7 +891,7 @@ next:
 out:
 	for (i = last_map; i < num; i++) {
 		/* Don't zap current batch's valid persistent grants. */
-		if(i >= map_until)
+		if (i >= map_until)
 			pages[i]->persistent_gnt = NULL;
 		pages[i]->handle = BLKBACK_INVALID_HANDLE;
 	}
@@ -931,7 +931,7 @@ static int xen_blkbk_parse_indirect(struct blkif_request *req,
 	if (rc)
 		goto unmap;
 
-	for (n = 0, i = 0; n < nseg; n++) {
+	for (n = 0; n < nseg; n++) {
 		uint8_t first_sect, last_sect;
 
 		if ((n % SEGS_PER_INDIRECT_FRAME) == 0) {
@@ -969,8 +969,7 @@ static int dispatch_discard_io(struct xen_blkif_ring *ring,
 	int err = 0;
 	int status = BLKIF_RSP_OKAY;
 	struct xen_blkif *blkif = ring->blkif;
-	struct block_device *bdev = blkif->vbd.bdev;
-	unsigned long secure;
+	struct block_device *bdev = file_bdev(blkif->vbd.bdev_file);
 	struct phys_req preq;
 
 	xen_blkif_get(blkif);
@@ -987,13 +986,15 @@ static int dispatch_discard_io(struct xen_blkif_ring *ring,
 	}
 	ring->st_ds_req++;
 
-	secure = (blkif->vbd.discard_secure &&
-		 (req->u.discard.flag & BLKIF_DISCARD_SECURE)) ?
-		 BLKDEV_DISCARD_SECURE : 0;
+	if (blkif->vbd.discard_secure &&
+	    (req->u.discard.flag & BLKIF_DISCARD_SECURE))
+		err = blkdev_issue_secure_erase(bdev,
+				req->u.discard.sector_number,
+				req->u.discard.nr_sectors, GFP_KERNEL);
+	else
+		err = blkdev_issue_discard(bdev, req->u.discard.sector_number,
+				req->u.discard.nr_sectors, GFP_KERNEL);
 
-	err = blkdev_issue_discard(bdev, req->u.discard.sector_number,
-				   req->u.discard.nr_sectors,
-				   GFP_KERNEL, secure);
 fail_response:
 	if (err == -EOPNOTSUPP) {
 		pr_debug("discard op failed, not supported\n");
@@ -1071,7 +1072,111 @@ static void end_block_io_op(struct bio *bio)
 	bio_put(bio);
 }
 
+static void blkif_get_x86_32_req(struct blkif_request *dst,
+				 const struct blkif_x86_32_request *src)
+{
+	unsigned int i, n;
+
+	dst->operation = READ_ONCE(src->operation);
+
+	switch (dst->operation) {
+	case BLKIF_OP_READ:
+	case BLKIF_OP_WRITE:
+	case BLKIF_OP_WRITE_BARRIER:
+	case BLKIF_OP_FLUSH_DISKCACHE:
+		dst->u.rw.nr_segments = READ_ONCE(src->u.rw.nr_segments);
+		dst->u.rw.handle = src->u.rw.handle;
+		dst->u.rw.id = src->u.rw.id;
+		dst->u.rw.sector_number = src->u.rw.sector_number;
+		n = min_t(unsigned int, BLKIF_MAX_SEGMENTS_PER_REQUEST,
+			  dst->u.rw.nr_segments);
+		for (i = 0; i < n; i++)
+			dst->u.rw.seg[i] = src->u.rw.seg[i];
+		break;
+
+	case BLKIF_OP_DISCARD:
+		dst->u.discard.flag = src->u.discard.flag;
+		dst->u.discard.id = src->u.discard.id;
+		dst->u.discard.sector_number = src->u.discard.sector_number;
+		dst->u.discard.nr_sectors = src->u.discard.nr_sectors;
+		break;
+
+	case BLKIF_OP_INDIRECT:
+		dst->u.indirect.indirect_op = src->u.indirect.indirect_op;
+		dst->u.indirect.nr_segments =
+			READ_ONCE(src->u.indirect.nr_segments);
+		dst->u.indirect.handle = src->u.indirect.handle;
+		dst->u.indirect.id = src->u.indirect.id;
+		dst->u.indirect.sector_number = src->u.indirect.sector_number;
+		n = min(MAX_INDIRECT_PAGES,
+			INDIRECT_PAGES(dst->u.indirect.nr_segments));
+		for (i = 0; i < n; i++)
+			dst->u.indirect.indirect_grefs[i] =
+				src->u.indirect.indirect_grefs[i];
+		break;
+
+	default:
+		/*
+		 * Don't know how to translate this op. Only get the
+		 * ID so failure can be reported to the frontend.
+		 */
+		dst->u.other.id = src->u.other.id;
+		break;
+	}
+}
+
+static void blkif_get_x86_64_req(struct blkif_request *dst,
+				 const struct blkif_x86_64_request *src)
+{
+	unsigned int i, n;
 
+	dst->operation = READ_ONCE(src->operation);
+
+	switch (dst->operation) {
+	case BLKIF_OP_READ:
+	case BLKIF_OP_WRITE:
+	case BLKIF_OP_WRITE_BARRIER:
+	case BLKIF_OP_FLUSH_DISKCACHE:
+		dst->u.rw.nr_segments = READ_ONCE(src->u.rw.nr_segments);
+		dst->u.rw.handle = src->u.rw.handle;
+		dst->u.rw.id = src->u.rw.id;
+		dst->u.rw.sector_number = src->u.rw.sector_number;
+		n = min_t(unsigned int, BLKIF_MAX_SEGMENTS_PER_REQUEST,
+			  dst->u.rw.nr_segments);
+		for (i = 0; i < n; i++)
+			dst->u.rw.seg[i] = src->u.rw.seg[i];
+		break;
+
+	case BLKIF_OP_DISCARD:
+		dst->u.discard.flag = src->u.discard.flag;
+		dst->u.discard.id = src->u.discard.id;
+		dst->u.discard.sector_number = src->u.discard.sector_number;
+		dst->u.discard.nr_sectors = src->u.discard.nr_sectors;
+		break;
+
+	case BLKIF_OP_INDIRECT:
+		dst->u.indirect.indirect_op = src->u.indirect.indirect_op;
+		dst->u.indirect.nr_segments =
+			READ_ONCE(src->u.indirect.nr_segments);
+		dst->u.indirect.handle = src->u.indirect.handle;
+		dst->u.indirect.id = src->u.indirect.id;
+		dst->u.indirect.sector_number = src->u.indirect.sector_number;
+		n = min(MAX_INDIRECT_PAGES,
+			INDIRECT_PAGES(dst->u.indirect.nr_segments));
+		for (i = 0; i < n; i++)
+			dst->u.indirect.indirect_grefs[i] =
+				src->u.indirect.indirect_grefs[i];
+		break;
+
+	default:
+		/*
+		 * Don't know how to translate this op. Only get the
+		 * ID so failure can be reported to the frontend.
+		 */
+		dst->u.other.id = src->u.other.id;
+		break;
+	}
+}
 
 /*
  * Function to copy the from the ring buffer the 'struct blkif_request'
@@ -1192,8 +1297,8 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 	struct bio *bio = NULL;
 	struct bio **biolist = pending_req->biolist;
 	int i, nbio = 0;
-	int operation;
-	int operation_flags = 0;
+	enum req_op operation;
+	blk_opf_t operation_flags = 0;
 	struct blk_plug plug;
 	bool drain = false;
 	struct grant_page **pages = pending_req->segments;
@@ -1326,16 +1431,13 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 				     pages[i]->page,
 				     seg[i].nsec << 9,
 				     seg[i].offset) == 0)) {
-			bio = bio_alloc(GFP_KERNEL, bio_max_segs(nseg - i));
-			if (unlikely(bio == NULL))
-				goto fail_put_bio;
-
+			bio = bio_alloc(preq.bdev, bio_max_segs(nseg - i),
+					operation | operation_flags,
+					GFP_KERNEL);
 			biolist[nbio++] = bio;
-			bio_set_dev(bio, preq.bdev);
 			bio->bi_private = pending_req;
 			bio->bi_end_io  = end_block_io_op;
 			bio->bi_iter.bi_sector  = preq.sector_number;
-			bio_set_op_attrs(bio, operation, operation_flags);
 		}
 
 		preq.sector_number += seg[i].nsec;
@@ -1345,15 +1447,11 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 	if (!bio) {
 		BUG_ON(operation_flags != REQ_PREFLUSH);
 
-		bio = bio_alloc(GFP_KERNEL, 0);
-		if (unlikely(bio == NULL))
-			goto fail_put_bio;
-
+		bio = bio_alloc(preq.bdev, 0, operation | operation_flags,
+				GFP_KERNEL);
 		biolist[nbio++] = bio;
-		bio_set_dev(bio, preq.bdev);
 		bio->bi_private = pending_req;
 		bio->bi_end_io  = end_block_io_op;
-		bio_set_op_attrs(bio, operation, operation_flags);
 	}
 
 	atomic_set(&pending_req->pendcnt, nbio);
@@ -1381,14 +1479,6 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 	free_req(ring, pending_req);
 	msleep(1); /* back off a bit */
 	return -EIO;
-
- fail_put_bio:
-	for (i = 0; i < nbio; i++)
-		bio_put(biolist[i]);
-	atomic_set(&pending_req->pendcnt, 1);
-	__end_block_io_op(pending_req, BLK_STS_RESOURCE);
-	msleep(1); /* back off a bit */
-	return -EIO;
 }
 
 
@@ -1473,5 +1563,6 @@ static void __exit xen_blkif_fini(void)
 
 module_exit(xen_blkif_fini);
 
+MODULE_DESCRIPTION("Virtual block device back-end driver");
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_ALIAS("xen-backend:vbd");