From 5b8e432dbb0e20bd8e99033f4a0bfa0d38c0e08e Mon Sep 17 00:00:00 2001 From: Dongli Zhang Date: Tue, 15 Jan 2019 00:41:43 +0800 Subject: [PATCH] xen/blkback: add stack variable 'blkif' in connect_ring() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As 'be->blkif' is used for many times in connect_ring(), the stack variable 'blkif' is added to substitute 'be-blkif'. Suggested-by: Paul Durrant Signed-off-by: Dongli Zhang Reviewed-by: Paul Durrant Reviewed-by: Roger Pau Monné Signed-off-by: Konrad Rzeszutek Wilk --- drivers/block/xen-blkback/xenbus.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index a4bc74e72c39..a4aadac772e5 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -1023,6 +1023,7 @@ fail: static int connect_ring(struct backend_info *be) { struct xenbus_device *dev = be->dev; + struct xen_blkif *blkif = be->blkif; unsigned int pers_grants; char protocol[64] = ""; int err, i; @@ -1033,25 +1034,25 @@ static int connect_ring(struct backend_info *be) pr_debug("%s %s\n", __func__, dev->otherend); - be->blkif->blk_protocol = BLKIF_PROTOCOL_DEFAULT; + blkif->blk_protocol = BLKIF_PROTOCOL_DEFAULT; err = xenbus_scanf(XBT_NIL, dev->otherend, "protocol", "%63s", protocol); if (err <= 0) strcpy(protocol, "unspecified, assuming default"); else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_NATIVE)) - be->blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE; + blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE; else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_32)) - be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_32; + blkif->blk_protocol = BLKIF_PROTOCOL_X86_32; else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_64)) - be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_64; + blkif->blk_protocol = BLKIF_PROTOCOL_X86_64; else { xenbus_dev_fatal(dev, err, "unknown fe protocol %s", protocol); return -ENOSYS; } pers_grants = xenbus_read_unsigned(dev->otherend, "feature-persistent", 0); - be->blkif->vbd.feature_gnt_persistent = pers_grants; - be->blkif->vbd.overflow_max_grants = 0; + blkif->vbd.feature_gnt_persistent = pers_grants; + blkif->vbd.overflow_max_grants = 0; /* * Read the number of hardware queues from frontend. @@ -1067,16 +1068,16 @@ static int connect_ring(struct backend_info *be) requested_num_queues, xenblk_max_queues); return -ENOSYS; } - be->blkif->nr_rings = requested_num_queues; - if (xen_blkif_alloc_rings(be->blkif)) + blkif->nr_rings = requested_num_queues; + if (xen_blkif_alloc_rings(blkif)) return -ENOMEM; pr_info("%s: using %d queues, protocol %d (%s) %s\n", dev->nodename, - be->blkif->nr_rings, be->blkif->blk_protocol, protocol, + blkif->nr_rings, blkif->blk_protocol, protocol, pers_grants ? "persistent grants" : ""); - if (be->blkif->nr_rings == 1) - return read_per_ring_refs(&be->blkif->rings[0], dev->otherend); + if (blkif->nr_rings == 1) + return read_per_ring_refs(&blkif->rings[0], dev->otherend); else { xspathsize = strlen(dev->otherend) + xenstore_path_ext_size; xspath = kmalloc(xspathsize, GFP_KERNEL); @@ -1085,10 +1086,10 @@ static int connect_ring(struct backend_info *be) return -ENOMEM; } - for (i = 0; i < be->blkif->nr_rings; i++) { + for (i = 0; i < blkif->nr_rings; i++) { memset(xspath, 0, xspathsize); snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend, i); - err = read_per_ring_refs(&be->blkif->rings[i], xspath); + err = read_per_ring_refs(&blkif->rings[i], xspath); if (err) { kfree(xspath); return err;