sunvdc: add cdrom and v1.1 protocol support

Interpret the media type from v1.1 protocol to support CDROM/DVD.

For v1.0 protocol, a disk's size continues to be calculated from the
geometry returned by the vdisk server. The geometry returned by the server
can be less than the actual number of sectors available in the backing
image/device due to the rounding in the division used to compute the
geometry in the vdisk server.

In v1.1 protocol a disk's actual size in sectors is returned during the
handshake. Use this size when v1.1 protocol is negotiated. Since this size
will always be larger than the former geometry computed size, disks created
under v1.0 will be forwards compatible to v1.1, but not vice versa.

Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 92 insertions, 17 deletions

diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c
index 5814deb6963d..66ddf704ad7f 100644
--- a/drivers/block/sunvdc.c
+++ b/drivers/block/sunvdc.c
@@ -9,6 +9,7 @@
 #include <linux/blkdev.h>
 #include <linux/hdreg.h>
 #include <linux/genhd.h>
+#include <linux/cdrom.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/completion.h>
@@ -22,8 +23,8 @@
 
 #define DRV_MODULE_NAME         "sunvdc"
 #define PFX DRV_MODULE_NAME     ": "
-#define DRV_MODULE_VERSION      "1.0"
-#define DRV_MODULE_RELDATE      "June 25, 2007"
+#define DRV_MODULE_VERSION      "1.1"
+#define DRV_MODULE_RELDATE      "February 13, 2013"
 
 static char version[] =
         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
@@ -65,6 +66,7 @@ struct vdc_port {
         u64                     operations;
         u32                     vdisk_size;
         u8                      vdisk_type;
+        u8                      vdisk_mtype;
 
         char                    disk_name[32];
 
@@ -79,9 +81,16 @@ static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
 
 /* Ordered from largest major to lowest */
 static struct vio_version vdc_versions[] = {
+        { .major = 1, .minor = 1 },
         { .major = 1, .minor = 0 },
 };
 
+static inline int vdc_version_supported(struct vdc_port *port,
+                                        u16 major, u16 minor)
+{
+        return port->vio.ver.major == major && port->vio.ver.minor >= minor;
+}
+
 #define VDCBLK_NAME     "vdisk"
 static int vdc_major;
 #define PARTITION_SHIFT 3
@@ -103,9 +112,41 @@ static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
         return 0;
 }
 
+/* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev
+ * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD.
+ * Needed to be able to install inside an ldom from an iso image.
+ */
+static int vdc_ioctl(struct block_device *bdev, fmode_t mode,
+                     unsigned command, unsigned long argument)
+{
+        int i;
+        struct gendisk *disk;
+
+        switch (command) {
+        case CDROMMULTISESSION:
+                pr_debug(PFX "Multisession CDs not supported\n");
+                for (i = 0; i < sizeof(struct cdrom_multisession); i++)
+                        if (put_user(0, (char __user *)(argument + i)))
+                                return -EFAULT;
+                return 0;
+
+        case CDROM_GET_CAPABILITY:
+                disk = bdev->bd_disk;
+
+                if (bdev->bd_disk && (disk->flags & GENHD_FL_CD))
+                        return 0;
+                return -EINVAL;
+
+        default:
+                pr_debug(PFX "ioctl %08x not supported\n", command);
+                return -EINVAL;
+        }
+}
+
 static const struct block_device_operations vdc_fops = {
         .owner          = THIS_MODULE,
         .getgeo         = vdc_getgeo,
+        .ioctl          = vdc_ioctl,
 };
 
 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
@@ -165,9 +206,9 @@ static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
         struct vio_disk_attr_info *pkt = arg;
 
         viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] "
-               "xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
+               "mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
                pkt->tag.stype, pkt->operations,
-               pkt->vdisk_size, pkt->vdisk_type,
+               pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype,
                pkt->xfer_mode, pkt->vdisk_block_size,
                pkt->max_xfer_size);
 
@@ -192,8 +233,11 @@ static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
                 }
 
                 port->operations = pkt->operations;
-                port->vdisk_size = pkt->vdisk_size;
                 port->vdisk_type = pkt->vdisk_type;
+                if (vdc_version_supported(port, 1, 1)) {
+                        port->vdisk_size = pkt->vdisk_size;
+                        port->vdisk_mtype = pkt->vdisk_mtype;
+                }
                 if (pkt->max_xfer_size < port->max_xfer_size)
                         port->max_xfer_size = pkt->max_xfer_size;
                 port->vdisk_block_size = pkt->vdisk_block_size;
@@ -663,18 +707,25 @@ static int probe_disk(struct vdc_port *port)
                 return err;
         }
 
-        err = generic_request(port, VD_OP_GET_DISKGEOM,
-                              &port->geom, sizeof(port->geom));
-        if (err < 0) {
-                printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
-                       "error %d\n", err);
-                return err;
+        if (vdc_version_supported(port, 1, 1)) {
+                /* vdisk_size should be set during the handshake, if it wasn't
+                 * then the underlying disk is reserved by another system
+                 */
+                if (port->vdisk_size == -1)
+                        return -ENODEV;
+        } else {
+                err = generic_request(port, VD_OP_GET_DISKGEOM,
+                                      &port->geom, sizeof(port->geom));
+                if (err < 0) {
+                        printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
+                               "error %d\n", err);
+                        return err;
+                }
+                port->vdisk_size = ((u64)port->geom.num_cyl *
+                                    (u64)port->geom.num_hd *
+                                    (u64)port->geom.num_sec);
         }
 
-        port->vdisk_size = ((u64)port->geom.num_cyl *
-                            (u64)port->geom.num_hd *
-                            (u64)port->geom.num_sec);
-
         q = blk_init_queue(do_vdc_request, &port->vio.lock);
         if (!q) {
                 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
@@ -704,9 +755,32 @@ static int probe_disk(struct vdc_port *port)
 
         set_capacity(g, port->vdisk_size);
 
-        printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
+        if (vdc_version_supported(port, 1, 1)) {
+                switch (port->vdisk_mtype) {
+                case VD_MEDIA_TYPE_CD:
+                        pr_info(PFX "Virtual CDROM %s\n", port->disk_name);
+                        g->flags |= GENHD_FL_CD;
+                        g->flags |= GENHD_FL_REMOVABLE;
+                        set_disk_ro(g, 1);
+                        break;
+
+                case VD_MEDIA_TYPE_DVD:
+                        pr_info(PFX "Virtual DVD %s\n", port->disk_name);
+                        g->flags |= GENHD_FL_CD;
+                        g->flags |= GENHD_FL_REMOVABLE;
+                        set_disk_ro(g, 1);
+                        break;
+
+                case VD_MEDIA_TYPE_FIXED:
+                        pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
+                        break;
+                }
+        }
+
+        pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n",
                g->disk_name,
-               port->vdisk_size, (port->vdisk_size >> (20 - 9)));
+               port->vdisk_size, (port->vdisk_size >> (20 - 9)),
+               port->vio.ver.major, port->vio.ver.minor);
 
         add_disk(g);
 
@@ -765,6 +839,7 @@ static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
         else
                 snprintf(port->disk_name, sizeof(port->disk_name),
                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
+        port->vdisk_size = -1;
 
         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
                               vdc_versions, ARRAY_SIZE(vdc_versions),