include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit...
[safe/jmp/linux-2.6] / drivers / block / virtio_blk.c
index 1980ab4..4b12b82 100644 (file)
@@ -1,5 +1,6 @@
 //#define DEBUG
 #include <linux/spinlock.h>
+#include <linux/slab.h>
 #include <linux/blkdev.h>
 #include <linux/hdreg.h>
 #include <linux/virtio.h>
@@ -37,6 +38,7 @@ struct virtblk_req
        struct list_head list;
        struct request *req;
        struct virtio_blk_outhdr out_hdr;
+       struct virtio_scsi_inhdr in_hdr;
        u8 status;
 };
 
@@ -50,6 +52,7 @@ static void blk_done(struct virtqueue *vq)
        spin_lock_irqsave(&vblk->lock, flags);
        while ((vbr = vblk->vq->vq_ops->get_buf(vblk->vq, &len)) != NULL) {
                int error;
+
                switch (vbr->status) {
                case VIRTIO_BLK_S_OK:
                        error = 0;
@@ -62,6 +65,12 @@ static void blk_done(struct virtqueue *vq)
                        break;
                }
 
+               if (blk_pc_request(vbr->req)) {
+                       vbr->req->resid_len = vbr->in_hdr.residual;
+                       vbr->req->sense_len = vbr->in_hdr.sense_len;
+                       vbr->req->errors = vbr->in_hdr.errors;
+               }
+
                __blk_end_request_all(vbr->req, error);
                list_del(&vbr->list);
                mempool_free(vbr, vblk->pool);
@@ -74,7 +83,7 @@ static void blk_done(struct virtqueue *vq)
 static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
                   struct request *req)
 {
-       unsigned long num, out, in;
+       unsigned long num, out = 0, in = 0;
        struct virtblk_req *vbr;
 
        vbr = mempool_alloc(vblk->pool, GFP_ATOMIC);
@@ -83,15 +92,26 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
                return false;
 
        vbr->req = req;
-       if (blk_fs_request(vbr->req)) {
+       switch (req->cmd_type) {
+       case REQ_TYPE_FS:
                vbr->out_hdr.type = 0;
                vbr->out_hdr.sector = blk_rq_pos(vbr->req);
                vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
-       } else if (blk_pc_request(vbr->req)) {
+               break;
+       case REQ_TYPE_BLOCK_PC:
                vbr->out_hdr.type = VIRTIO_BLK_T_SCSI_CMD;
                vbr->out_hdr.sector = 0;
                vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
-       } else {
+               break;
+       case REQ_TYPE_LINUX_BLOCK:
+               if (req->cmd[0] == REQ_LB_OP_FLUSH) {
+                       vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH;
+                       vbr->out_hdr.sector = 0;
+                       vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
+                       break;
+               }
+               /*FALLTHRU*/
+       default:
                /* We don't put anything else in the queue. */
                BUG();
        }
@@ -99,21 +119,39 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
        if (blk_barrier_rq(vbr->req))
                vbr->out_hdr.type |= VIRTIO_BLK_T_BARRIER;
 
-       sg_set_buf(&vblk->sg[0], &vbr->out_hdr, sizeof(vbr->out_hdr));
-       num = blk_rq_map_sg(q, vbr->req, vblk->sg+1);
-       sg_set_buf(&vblk->sg[num+1], &vbr->status, sizeof(vbr->status));
+       sg_set_buf(&vblk->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));
 
-       if (rq_data_dir(vbr->req) == WRITE) {
-               vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
-               out = 1 + num;
-               in = 1;
-       } else {
-               vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
-               out = 1;
-               in = 1 + num;
+       /*
+        * If this is a packet command we need a couple of additional headers.
+        * Behind the normal outhdr we put a segment with the scsi command
+        * block, and before the normal inhdr we put the sense data and the
+        * inhdr with additional status information before the normal inhdr.
+        */
+       if (blk_pc_request(vbr->req))
+               sg_set_buf(&vblk->sg[out++], vbr->req->cmd, vbr->req->cmd_len);
+
+       num = blk_rq_map_sg(q, vbr->req, vblk->sg + out);
+
+       if (blk_pc_request(vbr->req)) {
+               sg_set_buf(&vblk->sg[num + out + in++], vbr->req->sense, 96);
+               sg_set_buf(&vblk->sg[num + out + in++], &vbr->in_hdr,
+                          sizeof(vbr->in_hdr));
        }
 
-       if (vblk->vq->vq_ops->add_buf(vblk->vq, vblk->sg, out, in, vbr)) {
+       sg_set_buf(&vblk->sg[num + out + in++], &vbr->status,
+                  sizeof(vbr->status));
+
+       if (num) {
+               if (rq_data_dir(vbr->req) == WRITE) {
+                       vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
+                       out += num;
+               } else {
+                       vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
+                       in += num;
+               }
+       }
+
+       if (vblk->vq->vq_ops->add_buf(vblk->vq, vblk->sg, out, in, vbr) < 0) {
                mempool_free(vbr, vblk->pool);
                return false;
        }
@@ -124,12 +162,11 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
 
 static void do_virtblk_request(struct request_queue *q)
 {
-       struct virtio_blk *vblk = NULL;
+       struct virtio_blk *vblk = q->queuedata;
        struct request *req;
        unsigned int issued = 0;
 
-       while ((req = elv_next_request(q)) != NULL) {
-               vblk = req->rq_disk->private_data;
+       while ((req = blk_peek_request(q)) != NULL) {
                BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
 
                /* If this request fails, stop queue and wait for something to
@@ -138,7 +175,7 @@ static void do_virtblk_request(struct request_queue *q)
                        blk_stop_queue(q);
                        break;
                }
-               blkdev_dequeue_request(req);
+               blk_start_request(req);
                issued++;
        }
 
@@ -146,11 +183,25 @@ static void do_virtblk_request(struct request_queue *q)
                vblk->vq->vq_ops->kick(vblk->vq);
 }
 
+static void virtblk_prepare_flush(struct request_queue *q, struct request *req)
+{
+       req->cmd_type = REQ_TYPE_LINUX_BLOCK;
+       req->cmd[0] = REQ_LB_OP_FLUSH;
+}
+
 static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
                         unsigned cmd, unsigned long data)
 {
-       return scsi_cmd_ioctl(bdev->bd_disk->queue,
-                             bdev->bd_disk, mode, cmd,
+       struct gendisk *disk = bdev->bd_disk;
+       struct virtio_blk *vblk = disk->private_data;
+
+       /*
+        * Only allow the generic SCSI ioctls if the host can support it.
+        */
+       if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI))
+               return -ENOTTY;
+
+       return scsi_cmd_ioctl(disk->queue, disk, mode, cmd,
                              (void __user *)data);
 }
 
@@ -179,7 +230,7 @@ static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
        return 0;
 }
 
-static struct block_device_operations virtblk_fops = {
+static const struct block_device_operations virtblk_fops = {
        .locked_ioctl = virtblk_ioctl,
        .owner  = THIS_MODULE,
        .getgeo = virtblk_getgeo,
@@ -190,13 +241,15 @@ static int index_to_minor(int index)
        return index << PART_BITS;
 }
 
-static int virtblk_probe(struct virtio_device *vdev)
+static int __devinit virtblk_probe(struct virtio_device *vdev)
 {
        struct virtio_blk *vblk;
+       struct request_queue *q;
        int err;
        u64 cap;
-       u32 v;
-       u32 blk_size, sg_elems;
+       u32 v, blk_size, sg_elems, opt_io_size;
+       u16 min_io_size;
+       u8 physical_block_exp, alignment_offset;
 
        if (index_to_minor(index) >= 1 << MINORBITS)
                return -ENOSPC;
@@ -224,7 +277,7 @@ static int virtblk_probe(struct virtio_device *vdev)
        sg_init_table(vblk->sg, vblk->sg_elems);
 
        /* We expect one virtqueue, for output. */
-       vblk->vq = vdev->config->find_vq(vdev, 0, blk_done);
+       vblk->vq = virtio_find_single_vq(vdev, blk_done, "requests");
        if (IS_ERR(vblk->vq)) {
                err = PTR_ERR(vblk->vq);
                goto out_free_vblk;
@@ -243,13 +296,13 @@ static int virtblk_probe(struct virtio_device *vdev)
                goto out_mempool;
        }
 
-       vblk->disk->queue = blk_init_queue(do_virtblk_request, &vblk->lock);
-       if (!vblk->disk->queue) {
+       q = vblk->disk->queue = blk_init_queue(do_virtblk_request, &vblk->lock);
+       if (!q) {
                err = -ENOMEM;
                goto out_put_disk;
        }
 
-       queue_flag_set_unlocked(QUEUE_FLAG_VIRT, vblk->disk->queue);
+       q->queuedata = vblk;
 
        if (index < 26) {
                sprintf(vblk->disk->disk_name, "vd%c", 'a' + index % 26);
@@ -272,8 +325,11 @@ static int virtblk_probe(struct virtio_device *vdev)
        index++;
 
        /* If barriers are supported, tell block layer that queue is ordered */
-       if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER))
-               blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_TAG, NULL);
+       if (virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH))
+               blk_queue_ordered(q, QUEUE_ORDERED_DRAIN_FLUSH,
+                                 virtblk_prepare_flush);
+       else if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER))
+               blk_queue_ordered(q, QUEUE_ORDERED_TAG, NULL);
 
        /* If disk is read-only in the host, the guest should obey */
        if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))
@@ -292,11 +348,14 @@ static int virtblk_probe(struct virtio_device *vdev)
        set_capacity(vblk->disk, cap);
 
        /* We can handle whatever the host told us to handle. */
-       blk_queue_max_phys_segments(vblk->disk->queue, vblk->sg_elems-2);
-       blk_queue_max_hw_segments(vblk->disk->queue, vblk->sg_elems-2);
+       blk_queue_max_phys_segments(q, vblk->sg_elems-2);
+       blk_queue_max_hw_segments(q, vblk->sg_elems-2);
+
+       /* No need to bounce any requests */
+       blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
 
        /* No real sector limit. */
-       blk_queue_max_sectors(vblk->disk->queue, -1U);
+       blk_queue_max_sectors(q, -1U);
 
        /* Host can optionally specify maximum segment size and number of
         * segments. */
@@ -304,16 +363,45 @@ static int virtblk_probe(struct virtio_device *vdev)
                                offsetof(struct virtio_blk_config, size_max),
                                &v);
        if (!err)
-               blk_queue_max_segment_size(vblk->disk->queue, v);
+               blk_queue_max_segment_size(q, v);
        else
-               blk_queue_max_segment_size(vblk->disk->queue, -1U);
+               blk_queue_max_segment_size(q, -1U);
 
        /* Host can optionally specify the block size of the device */
        err = virtio_config_val(vdev, VIRTIO_BLK_F_BLK_SIZE,
                                offsetof(struct virtio_blk_config, blk_size),
                                &blk_size);
        if (!err)
-               blk_queue_hardsect_size(vblk->disk->queue, blk_size);
+               blk_queue_logical_block_size(q, blk_size);
+       else
+               blk_size = queue_logical_block_size(q);
+
+       /* Use topology information if available */
+       err = virtio_config_val(vdev, VIRTIO_BLK_F_TOPOLOGY,
+                       offsetof(struct virtio_blk_config, physical_block_exp),
+                       &physical_block_exp);
+       if (!err && physical_block_exp)
+               blk_queue_physical_block_size(q,
+                               blk_size * (1 << physical_block_exp));
+
+       err = virtio_config_val(vdev, VIRTIO_BLK_F_TOPOLOGY,
+                       offsetof(struct virtio_blk_config, alignment_offset),
+                       &alignment_offset);
+       if (!err && alignment_offset)
+               blk_queue_alignment_offset(q, blk_size * alignment_offset);
+
+       err = virtio_config_val(vdev, VIRTIO_BLK_F_TOPOLOGY,
+                       offsetof(struct virtio_blk_config, min_io_size),
+                       &min_io_size);
+       if (!err && min_io_size)
+               blk_queue_io_min(q, blk_size * min_io_size);
+
+       err = virtio_config_val(vdev, VIRTIO_BLK_F_TOPOLOGY,
+                       offsetof(struct virtio_blk_config, opt_io_size),
+                       &opt_io_size);
+       if (!err && opt_io_size)
+               blk_queue_io_opt(q, blk_size * opt_io_size);
+
 
        add_disk(vblk->disk);
        return 0;
@@ -323,14 +411,14 @@ out_put_disk:
 out_mempool:
        mempool_destroy(vblk->pool);
 out_free_vq:
-       vdev->config->del_vq(vblk->vq);
+       vdev->config->del_vqs(vdev);
 out_free_vblk:
        kfree(vblk);
 out:
        return err;
 }
 
-static void virtblk_remove(struct virtio_device *vdev)
+static void __devexit virtblk_remove(struct virtio_device *vdev)
 {
        struct virtio_blk *vblk = vdev->priv;
 
@@ -344,11 +432,11 @@ static void virtblk_remove(struct virtio_device *vdev)
        blk_cleanup_queue(vblk->disk->queue);
        put_disk(vblk->disk);
        mempool_destroy(vblk->pool);
-       vdev->config->del_vq(vblk->vq);
+       vdev->config->del_vqs(vdev);
        kfree(vblk);
 }
 
-static struct virtio_device_id id_table[] = {
+static const struct virtio_device_id id_table[] = {
        { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
        { 0 },
 };
@@ -356,9 +444,15 @@ static struct virtio_device_id id_table[] = {
 static unsigned int features[] = {
        VIRTIO_BLK_F_BARRIER, VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX,
        VIRTIO_BLK_F_GEOMETRY, VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE,
+       VIRTIO_BLK_F_SCSI, VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY
 };
 
-static struct virtio_driver virtio_blk = {
+/*
+ * virtio_blk causes spurious section mismatch warning by
+ * simultaneously referring to a __devinit and a __devexit function.
+ * Use __refdata to avoid this warning.
+ */
+static struct virtio_driver __refdata virtio_blk = {
        .feature_table = features,
        .feature_table_size = ARRAY_SIZE(features),
        .driver.name =  KBUILD_MODNAME,