[POWERPC] iSeries: Move viodasd probing

This way we only have entries in the device tree for disks that actually
exist.  A slight complication is that disks may be attached to LPARs
at runtime.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/platforms/iseries/dt.c

@@ -72,7 +72,6 @@ static char __initdata device_type_cpu[] = "cpu";
 static char __initdata device_type_memory[] = "memory";
 static char __initdata device_type_serial[] = "serial";
 static char __initdata device_type_network[] = "network";
-static char __initdata device_type_block[] = "block";
 static char __initdata device_type_pci[] = "pci";
 static char __initdata device_type_vdevice[] = "vdevice";
 static char __initdata device_type_vscsi[] = "vscsi";
@@ -374,11 +373,6 @@ static void __init dt_vdevices(struct iseries_flat_dt *dt)
 
 		dt_end_node(dt);
 	}
-	reg += HVMAXARCHITECTEDVIRTUALLANS;
-
-	for (i = 0; i < HVMAXARCHITECTEDVIRTUALDISKS; i++)
-		dt_do_vdevice(dt, "viodasd", reg, i, device_type_block,
-				"IBM,iSeries-viodasd", 1);
 
 	dt_end_node(dt);
 }

drivers/block/viodasd.c

@@ -74,53 +74,9 @@ enum {
 static DEFINE_SPINLOCK(viodasd_spinlock);
 
 #define VIOMAXREQ		16
-#define VIOMAXBLOCKDMA		12
 
 #define DEVICE_NO(cell)	((struct viodasd_device *)(cell) - &viodasd_devices[0])
 
-struct open_data {
-	u64	disk_size;
-	u16	max_disk;
-	u16	cylinders;
-	u16	tracks;
-	u16	sectors;
-	u16	bytes_per_sector;
-};
-
-struct rw_data {
-	u64	offset;
-	struct {
-		u32	token;
-		u32	reserved;
-		u64	len;
-	} dma_info[VIOMAXBLOCKDMA];
-};
-
-struct vioblocklpevent {
-	struct HvLpEvent	event;
-	u32			reserved;
-	u16			version;
-	u16			sub_result;
-	u16			disk;
-	u16			flags;
-	union {
-		struct open_data	open_data;
-		struct rw_data		rw_data;
-		u64			changed;
-	} u;
-};
-
-#define vioblockflags_ro   0x0001
-
-enum vioblocksubtype {
-	vioblockopen = 0x0001,
-	vioblockclose = 0x0002,
-	vioblockread = 0x0003,
-	vioblockwrite = 0x0004,
-	vioblockflush = 0x0005,
-	vioblockcheck = 0x0007
-};
-
 struct viodasd_waitevent {
 	struct completion	com;
 	int			rc;
@@ -429,7 +385,7 @@ static void do_viodasd_request(struct request_queue *q)
  * Probe a single disk and fill in the viodasd_device structure
  * for it.
  */
-static void probe_disk(struct viodasd_device *d)
+static int probe_disk(struct viodasd_device *d)
 {
 	HvLpEvent_Rc hvrc;
 	struct viodasd_waitevent we;
@@ -453,14 +409,14 @@ static void probe_disk(struct viodasd_device *d)
 			0, 0, 0);
 	if (hvrc != 0) {
 		printk(VIOD_KERN_WARNING "bad rc on HV open %d\n", (int)hvrc);
-		return;
+		return 0;
 	}
 
 	wait_for_completion(&we.com);
 
 	if (we.rc != 0) {
 		if (flags != 0)
-			return;
+			return 0;
 		/* try again with read only flag set */
 		flags = vioblockflags_ro;
 		goto retry;
@@ -490,15 +446,32 @@ static void probe_disk(struct viodasd_device *d)
 	if (hvrc != 0) {
 		printk(VIOD_KERN_WARNING
 		       "bad rc sending event to OS/400 %d\n", (int)hvrc);
-		return;
+		return 0;
 	}
+
+	if (d->dev == NULL) {
+		/* this is when we reprobe for new disks */
+		if (vio_create_viodasd(dev_no) == NULL) {
+			printk(VIOD_KERN_WARNING
+				"cannot allocate virtual device for disk %d\n",
+				dev_no);
+			return 0;
+		}
+		/*
+		 * The vio_create_viodasd will have recursed into this
+		 * routine with d->dev set to the new vio device and
+		 * will finish the setup of the disk below.
+		 */
+		return 1;
+	}
+
 	/* create the request queue for the disk */
 	spin_lock_init(&d->q_lock);
 	q = blk_init_queue(do_viodasd_request, &d->q_lock);
 	if (q == NULL) {
 		printk(VIOD_KERN_WARNING "cannot allocate queue for disk %d\n",
 				dev_no);
-		return;
+		return 0;
 	}
 	g = alloc_disk(1 << PARTITION_SHIFT);
 	if (g == NULL) {
@@ -506,7 +479,7 @@ static void probe_disk(struct viodasd_device *d)
 				"cannot allocate disk structure for disk %d\n",
 				dev_no);
 		blk_cleanup_queue(q);
-		return;
+		return 0;
 	}
 
 	d->disk = g;
@@ -538,6 +511,7 @@ static void probe_disk(struct viodasd_device *d)
 
 	/* register us in the global list */
 	add_disk(g);
+	return 1;
 }
 
 /* returns the total number of scatterlist elements converted */
@@ -718,8 +692,7 @@ static int viodasd_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 	struct viodasd_device *d = &viodasd_devices[vdev->unit_address];
 
 	d->dev = &vdev->dev;
-	probe_disk(d);
-	if (d->disk == NULL)
+	if (!probe_disk(d))
 		return -ENODEV;
 	return 0;
 }

include/asm-powerpc/iseries/vio.h

@@ -51,6 +51,51 @@
  */
 #define VIO_MAX_SUBTYPES 8
 
+#define VIOMAXBLOCKDMA	12
+
+struct open_data {
+	u64	disk_size;
+	u16	max_disk;
+	u16	cylinders;
+	u16	tracks;
+	u16	sectors;
+	u16	bytes_per_sector;
+};
+
+struct rw_data {
+	u64	offset;
+	struct {
+		u32	token;
+		u32	reserved;
+		u64	len;
+	} dma_info[VIOMAXBLOCKDMA];
+};
+
+struct vioblocklpevent {
+	struct HvLpEvent	event;
+	u32			reserved;
+	u16			version;
+	u16			sub_result;
+	u16			disk;
+	u16			flags;
+	union {
+		struct open_data	open_data;
+		struct rw_data		rw_data;
+		u64			changed;
+	} u;
+};
+
+#define vioblockflags_ro   0x0001
+
+enum vioblocksubtype {
+	vioblockopen = 0x0001,
+	vioblockclose = 0x0002,
+	vioblockread = 0x0003,
+	vioblockwrite = 0x0004,
+	vioblockflush = 0x0005,
+	vioblockcheck = 0x0007
+};
+
 struct viocdlpevent {
 	struct HvLpEvent	event;
 	u32			reserved;
@@ -133,6 +178,8 @@ extern void vio_set_hostlp(void);
 extern void *vio_get_event_buffer(int subtype);
 extern void vio_free_event_buffer(int subtype, void *buffer);
 
+extern struct vio_dev *vio_create_viodasd(u32 unit);
+
 extern HvLpIndex viopath_hostLp;
 extern HvLpIndex viopath_ourLp;