virtio_blk: split virtblk_probe

Split out a virtblk_read_limits helper that just reads the various
queue limits to separate it from the higher level probing logic.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240213073425.1621680-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index a23fce4..dd46ccd 100644 (file)
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -1248,31 +1248,17 @@ static const struct blk_mq_ops virtio_mq_ops = {
 static unsigned int virtblk_queue_depth;
 module_param_named(queue_depth, virtblk_queue_depth, uint, 0444);
 
-static int virtblk_probe(struct virtio_device *vdev)
+static int virtblk_read_limits(struct virtio_blk *vblk)
 {
-       struct virtio_blk *vblk;
-       struct request_queue *q;
-       int err, index;
-
+       struct request_queue *q = vblk->disk->queue;
+       struct virtio_device *vdev = vblk->vdev;
        u32 v, blk_size, max_size, sg_elems, opt_io_size;
        u32 max_discard_segs = 0;
        u32 discard_granularity = 0;
        u16 min_io_size;
        u8 physical_block_exp, alignment_offset;
-       unsigned int queue_depth;
        size_t max_dma_size;
-
-       if (!vdev->config->get) {
-               dev_err(&vdev->dev, "%s failure: config access disabled\n",
-                       __func__);
-               return -EINVAL;
-       }
-
-       err = ida_alloc_range(&vd_index_ida, 0,
-                             minor_to_index(1 << MINORBITS) - 1, GFP_KERNEL);
-       if (err < 0)
-               goto out;
-       index = err;
+       int err;
 
        /* We need to know how many segments before we allocate. */
        err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SEG_MAX,
@@ -1286,73 +1272,6 @@ static int virtblk_probe(struct virtio_device *vdev)
        /* Prevent integer overflows and honor max vq size */
        sg_elems = min_t(u32, sg_elems, VIRTIO_BLK_MAX_SG_ELEMS - 2);
 
-       vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL);
-       if (!vblk) {
-               err = -ENOMEM;
-               goto out_free_index;
-       }
-
-       mutex_init(&vblk->vdev_mutex);
-
-       vblk->vdev = vdev;
-
-       INIT_WORK(&vblk->config_work, virtblk_config_changed_work);
-
-       err = init_vq(vblk);
-       if (err)
-               goto out_free_vblk;
-
-       /* Default queue sizing is to fill the ring. */
-       if (!virtblk_queue_depth) {
-               queue_depth = vblk->vqs[0].vq->num_free;
-               /* ... but without indirect descs, we use 2 descs per req */
-               if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC))
-                       queue_depth /= 2;
-       } else {
-               queue_depth = virtblk_queue_depth;
-       }
-
-       memset(&vblk->tag_set, 0, sizeof(vblk->tag_set));
-       vblk->tag_set.ops = &virtio_mq_ops;
-       vblk->tag_set.queue_depth = queue_depth;
-       vblk->tag_set.numa_node = NUMA_NO_NODE;
-       vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
-       vblk->tag_set.cmd_size =
-               sizeof(struct virtblk_req) +
-               sizeof(struct scatterlist) * VIRTIO_BLK_INLINE_SG_CNT;
-       vblk->tag_set.driver_data = vblk;
-       vblk->tag_set.nr_hw_queues = vblk->num_vqs;
-       vblk->tag_set.nr_maps = 1;
-       if (vblk->io_queues[HCTX_TYPE_POLL])
-               vblk->tag_set.nr_maps = 3;
-
-       err = blk_mq_alloc_tag_set(&vblk->tag_set);
-       if (err)
-               goto out_free_vq;
-
-       vblk->disk = blk_mq_alloc_disk(&vblk->tag_set, NULL, vblk);
-       if (IS_ERR(vblk->disk)) {
-               err = PTR_ERR(vblk->disk);
-               goto out_free_tags;
-       }
-       q = vblk->disk->queue;
-
-       virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN);
-
-       vblk->disk->major = major;
-       vblk->disk->first_minor = index_to_minor(index);
-       vblk->disk->minors = 1 << PART_BITS;
-       vblk->disk->private_data = vblk;
-       vblk->disk->fops = &virtblk_fops;
-       vblk->index = index;
-
-       /* configure queue flush support */
-       virtblk_update_cache_mode(vdev);
-
-       /* If disk is read-only in the host, the guest should obey */
-       if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))
-               set_disk_ro(vblk->disk, 1);
-
        /* We can handle whatever the host told us to handle. */
        blk_queue_max_segments(q, sg_elems);
 
@@ -1381,7 +1300,7 @@ static int virtblk_probe(struct virtio_device *vdev)
                        dev_err(&vdev->dev,
                                "virtio_blk: invalid block size: 0x%x\n",
                                blk_size);
-                       goto out_cleanup_disk;
+                       return err;
                }
 
                blk_queue_logical_block_size(q, blk_size);
@@ -1455,8 +1374,7 @@ static int virtblk_probe(struct virtio_device *vdev)
                if (!v) {
                        dev_err(&vdev->dev,
                                "virtio_blk: secure_erase_sector_alignment can't be 0\n");
-                       err = -EINVAL;
-                       goto out_cleanup_disk;
+                       return -EINVAL;
                }
 
                discard_granularity = min_not_zero(discard_granularity, v);
@@ -1470,8 +1388,7 @@ static int virtblk_probe(struct virtio_device *vdev)
                if (!v) {
                        dev_err(&vdev->dev,
                                "virtio_blk: max_secure_erase_sectors can't be 0\n");
-                       err = -EINVAL;
-                       goto out_cleanup_disk;
+                       return -EINVAL;
                }
 
                blk_queue_max_secure_erase_sectors(q, v);
@@ -1485,8 +1402,7 @@ static int virtblk_probe(struct virtio_device *vdev)
                if (!v) {
                        dev_err(&vdev->dev,
                                "virtio_blk: max_secure_erase_seg can't be 0\n");
-                       err = -EINVAL;
-                       goto out_cleanup_disk;
+                       return -EINVAL;
                }
 
                max_discard_segs = min_not_zero(max_discard_segs, v);
@@ -1511,6 +1427,99 @@ static int virtblk_probe(struct virtio_device *vdev)
                        q->limits.discard_granularity = blk_size;
        }
 
+       return 0;
+}
+
+static int virtblk_probe(struct virtio_device *vdev)
+{
+       struct virtio_blk *vblk;
+       struct request_queue *q;
+       int err, index;
+       unsigned int queue_depth;
+
+       if (!vdev->config->get) {
+               dev_err(&vdev->dev, "%s failure: config access disabled\n",
+                       __func__);
+               return -EINVAL;
+       }
+
+       err = ida_alloc_range(&vd_index_ida, 0,
+                             minor_to_index(1 << MINORBITS) - 1, GFP_KERNEL);
+       if (err < 0)
+               goto out;
+       index = err;
+
+       vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL);
+       if (!vblk) {
+               err = -ENOMEM;
+               goto out_free_index;
+       }
+
+       mutex_init(&vblk->vdev_mutex);
+
+       vblk->vdev = vdev;
+
+       INIT_WORK(&vblk->config_work, virtblk_config_changed_work);
+
+       err = init_vq(vblk);
+       if (err)
+               goto out_free_vblk;
+
+       /* Default queue sizing is to fill the ring. */
+       if (!virtblk_queue_depth) {
+               queue_depth = vblk->vqs[0].vq->num_free;
+               /* ... but without indirect descs, we use 2 descs per req */
+               if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC))
+                       queue_depth /= 2;
+       } else {
+               queue_depth = virtblk_queue_depth;
+       }
+
+       memset(&vblk->tag_set, 0, sizeof(vblk->tag_set));
+       vblk->tag_set.ops = &virtio_mq_ops;
+       vblk->tag_set.queue_depth = queue_depth;
+       vblk->tag_set.numa_node = NUMA_NO_NODE;
+       vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+       vblk->tag_set.cmd_size =
+               sizeof(struct virtblk_req) +
+               sizeof(struct scatterlist) * VIRTIO_BLK_INLINE_SG_CNT;
+       vblk->tag_set.driver_data = vblk;
+       vblk->tag_set.nr_hw_queues = vblk->num_vqs;
+       vblk->tag_set.nr_maps = 1;
+       if (vblk->io_queues[HCTX_TYPE_POLL])
+               vblk->tag_set.nr_maps = 3;
+
+       err = blk_mq_alloc_tag_set(&vblk->tag_set);
+       if (err)
+               goto out_free_vq;
+
+       vblk->disk = blk_mq_alloc_disk(&vblk->tag_set, NULL, vblk);
+       if (IS_ERR(vblk->disk)) {
+               err = PTR_ERR(vblk->disk);
+               goto out_free_tags;
+       }
+       q = vblk->disk->queue;
+
+       virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN);
+
+       vblk->disk->major = major;
+       vblk->disk->first_minor = index_to_minor(index);
+       vblk->disk->minors = 1 << PART_BITS;
+       vblk->disk->private_data = vblk;
+       vblk->disk->fops = &virtblk_fops;
+       vblk->index = index;
+
+       /* configure queue flush support */
+       virtblk_update_cache_mode(vdev);
+
+       /* If disk is read-only in the host, the guest should obey */
+       if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))
+               set_disk_ro(vblk->disk, 1);
+
+       err = virtblk_read_limits(vblk);
+       if (err)
+               goto out_cleanup_disk;
+
        virtblk_update_capacity(vblk, false);
        virtio_device_ready(vdev);