1 /* sunvdc.c: Sun LDOM Virtual Disk Client.
3 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/types.h>
9 #include <linux/blkdev.h>
10 #include <linux/hdreg.h>
11 #include <linux/genhd.h>
12 #include <linux/slab.h>
13 #include <linux/spinlock.h>
14 #include <linux/completion.h>
15 #include <linux/delay.h>
16 #include <linux/init.h>
17 #include <linux/list.h>
18 #include <linux/scatterlist.h>
23 #define DRV_MODULE_NAME "sunvdc"
24 #define PFX DRV_MODULE_NAME ": "
25 #define DRV_MODULE_VERSION "1.0"
26 #define DRV_MODULE_RELDATE "June 25, 2007"
28 static char version[] __devinitdata =
29 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
30 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
31 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
32 MODULE_LICENSE("GPL");
33 MODULE_VERSION(DRV_MODULE_VERSION);
35 #define VDC_TX_RING_SIZE 256
37 #define WAITING_FOR_LINK_UP 0x01
38 #define WAITING_FOR_TX_SPACE 0x02
39 #define WAITING_FOR_GEN_CMD 0x04
40 #define WAITING_FOR_ANY -1
42 struct vdc_req_entry {
47 struct vio_driver_state vio;
51 struct vdc_completion *cmp;
55 struct vdc_req_entry rq_arr[VDC_TX_RING_SIZE];
57 unsigned long ring_cookies;
62 /* The server fills these in for us in the disk attribute
71 struct vio_disk_geom geom;
72 struct vio_disk_vtoc label;
75 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
77 return container_of(vio, struct vdc_port, vio);
80 /* Ordered from largest major to lowest */
81 static struct vio_version vdc_versions[] = {
82 { .major = 1, .minor = 0 },
85 #define VDCBLK_NAME "vdisk"
87 #define PARTITION_SHIFT 3
89 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
91 return vio_dring_avail(dr, VDC_TX_RING_SIZE);
94 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
96 struct gendisk *disk = bdev->bd_disk;
97 struct vdc_port *port = disk->private_data;
99 geo->heads = (u8) port->geom.num_hd;
100 geo->sectors = (u8) port->geom.num_sec;
101 geo->cylinders = port->geom.num_cyl;
106 static struct block_device_operations vdc_fops = {
107 .owner = THIS_MODULE,
108 .getgeo = vdc_getgeo,
111 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
114 (waiting_for == -1 ||
115 vio->cmp->waiting_for == waiting_for)) {
117 complete(&vio->cmp->com);
122 static void vdc_handshake_complete(struct vio_driver_state *vio)
124 vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
127 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
129 struct vio_msg_tag *pkt = arg;
131 printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
132 pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
133 printk(KERN_ERR PFX "Resetting connection.\n");
135 ldc_disconnect(port->vio.lp);
140 static int vdc_send_attr(struct vio_driver_state *vio)
142 struct vdc_port *port = to_vdc_port(vio);
143 struct vio_disk_attr_info pkt;
145 memset(&pkt, 0, sizeof(pkt));
147 pkt.tag.type = VIO_TYPE_CTRL;
148 pkt.tag.stype = VIO_SUBTYPE_INFO;
149 pkt.tag.stype_env = VIO_ATTR_INFO;
150 pkt.tag.sid = vio_send_sid(vio);
152 pkt.xfer_mode = VIO_DRING_MODE;
153 pkt.vdisk_block_size = port->vdisk_block_size;
154 pkt.max_xfer_size = port->max_xfer_size;
156 viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
157 pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
159 return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
162 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
164 struct vdc_port *port = to_vdc_port(vio);
165 struct vio_disk_attr_info *pkt = arg;
167 viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] "
168 "xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
169 pkt->tag.stype, pkt->operations,
170 pkt->vdisk_size, pkt->vdisk_type,
171 pkt->xfer_mode, pkt->vdisk_block_size,
174 if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
175 switch (pkt->vdisk_type) {
176 case VD_DISK_TYPE_DISK:
177 case VD_DISK_TYPE_SLICE:
181 printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
182 vio->name, pkt->vdisk_type);
186 if (pkt->vdisk_block_size > port->vdisk_block_size) {
187 printk(KERN_ERR PFX "%s: BLOCK size increased "
190 port->vdisk_block_size, pkt->vdisk_block_size);
194 port->operations = pkt->operations;
195 port->vdisk_size = pkt->vdisk_size;
196 port->vdisk_type = pkt->vdisk_type;
197 if (pkt->max_xfer_size < port->max_xfer_size)
198 port->max_xfer_size = pkt->max_xfer_size;
199 port->vdisk_block_size = pkt->vdisk_block_size;
202 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
208 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
210 int err = desc->status;
212 vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
215 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
218 struct vio_disk_desc *desc = vio_dring_entry(dr, index);
219 struct vdc_req_entry *rqe = &port->rq_arr[index];
222 if (unlikely(desc->hdr.state != VIO_DESC_DONE))
225 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
226 desc->hdr.state = VIO_DESC_FREE;
227 dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
231 vdc_end_special(port, desc);
237 __blk_end_request(req, (desc->status ? -EIO : 0), desc->size);
239 if (blk_queue_stopped(port->disk->queue))
240 blk_start_queue(port->disk->queue);
243 static int vdc_ack(struct vdc_port *port, void *msgbuf)
245 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
246 struct vio_dring_data *pkt = msgbuf;
248 if (unlikely(pkt->dring_ident != dr->ident ||
249 pkt->start_idx != pkt->end_idx ||
250 pkt->start_idx >= VDC_TX_RING_SIZE))
253 vdc_end_one(port, dr, pkt->start_idx);
258 static int vdc_nack(struct vdc_port *port, void *msgbuf)
260 /* XXX Implement me XXX */
264 static void vdc_event(void *arg, int event)
266 struct vdc_port *port = arg;
267 struct vio_driver_state *vio = &port->vio;
271 spin_lock_irqsave(&vio->lock, flags);
273 if (unlikely(event == LDC_EVENT_RESET ||
274 event == LDC_EVENT_UP)) {
275 vio_link_state_change(vio, event);
276 spin_unlock_irqrestore(&vio->lock, flags);
280 if (unlikely(event != LDC_EVENT_DATA_READY)) {
281 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
282 spin_unlock_irqrestore(&vio->lock, flags);
289 struct vio_msg_tag tag;
293 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
294 if (unlikely(err < 0)) {
295 if (err == -ECONNRESET)
301 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
304 msgbuf.tag.stype_env,
306 err = vio_validate_sid(vio, &msgbuf.tag);
310 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
311 if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
312 err = vdc_ack(port, &msgbuf);
313 else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
314 err = vdc_nack(port, &msgbuf);
316 err = vdc_handle_unknown(port, &msgbuf);
317 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
318 err = vio_control_pkt_engine(vio, &msgbuf);
320 err = vdc_handle_unknown(port, &msgbuf);
326 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
327 spin_unlock_irqrestore(&vio->lock, flags);
330 static int __vdc_tx_trigger(struct vdc_port *port)
332 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
333 struct vio_dring_data hdr = {
335 .type = VIO_TYPE_DATA,
336 .stype = VIO_SUBTYPE_INFO,
337 .stype_env = VIO_DRING_DATA,
338 .sid = vio_send_sid(&port->vio),
340 .dring_ident = dr->ident,
341 .start_idx = dr->prod,
346 hdr.seq = dr->snd_nxt;
349 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
355 if ((delay <<= 1) > 128)
357 } while (err == -EAGAIN);
362 static int __send_request(struct request *req)
364 struct vdc_port *port = req->rq_disk->private_data;
365 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
366 struct scatterlist sg[port->ring_cookies];
367 struct vdc_req_entry *rqe;
368 struct vio_disk_desc *desc;
369 unsigned int map_perm;
374 map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
376 if (rq_data_dir(req) == READ) {
377 map_perm |= LDC_MAP_W;
380 map_perm |= LDC_MAP_R;
384 sg_init_table(sg, port->ring_cookies);
385 nsg = blk_rq_map_sg(req->q, req, sg);
388 for (i = 0; i < nsg; i++)
391 if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
392 blk_stop_queue(port->disk->queue);
397 desc = vio_dring_cur(dr);
399 err = ldc_map_sg(port->vio.lp, sg, nsg,
400 desc->cookies, port->ring_cookies,
403 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
407 rqe = &port->rq_arr[dr->prod];
410 desc->hdr.ack = VIO_ACK_ENABLE;
411 desc->req_id = port->req_id;
412 desc->operation = op;
413 if (port->vdisk_type == VD_DISK_TYPE_DISK) {
419 desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size;
421 desc->ncookies = err;
423 /* This has to be a non-SMP write barrier because we are writing
424 * to memory which is shared with the peer LDOM.
427 desc->hdr.state = VIO_DESC_READY;
429 err = __vdc_tx_trigger(port);
431 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
434 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
441 static void do_vdc_request(struct request_queue *q)
444 struct request *req = elv_next_request(q);
449 blkdev_dequeue_request(req);
450 if (__send_request(req) < 0)
451 __blk_end_request_all(req, -EIO);
455 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
457 struct vio_dring_state *dr;
458 struct vio_completion comp;
459 struct vio_disk_desc *desc;
460 unsigned int map_perm;
465 if (!(((u64)1 << ((u64)op - 1)) & port->operations))
480 op_len = sizeof(u32);
481 map_perm = LDC_MAP_W;
485 op_len = sizeof(u32);
486 map_perm = LDC_MAP_R;
490 op_len = sizeof(struct vio_disk_vtoc);
491 map_perm = LDC_MAP_W;
495 op_len = sizeof(struct vio_disk_vtoc);
496 map_perm = LDC_MAP_R;
499 case VD_OP_GET_DISKGEOM:
500 op_len = sizeof(struct vio_disk_geom);
501 map_perm = LDC_MAP_W;
504 case VD_OP_SET_DISKGEOM:
505 op_len = sizeof(struct vio_disk_geom);
506 map_perm = LDC_MAP_R;
511 map_perm = LDC_MAP_RW;
514 case VD_OP_GET_DEVID:
515 op_len = sizeof(struct vio_disk_devid);
516 map_perm = LDC_MAP_W;
525 map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
527 op_len = (op_len + 7) & ~7;
528 req_buf = kzalloc(op_len, GFP_KERNEL);
535 if (map_perm & LDC_MAP_R)
536 memcpy(req_buf, buf, len);
538 spin_lock_irqsave(&port->vio.lock, flags);
540 dr = &port->vio.drings[VIO_DRIVER_TX_RING];
542 /* XXX If we want to use this code generically we have to
543 * XXX handle TX ring exhaustion etc.
545 desc = vio_dring_cur(dr);
547 err = ldc_map_single(port->vio.lp, req_buf, op_len,
548 desc->cookies, port->ring_cookies,
551 spin_unlock_irqrestore(&port->vio.lock, flags);
556 init_completion(&comp.com);
557 comp.waiting_for = WAITING_FOR_GEN_CMD;
558 port->vio.cmp = ∁
560 desc->hdr.ack = VIO_ACK_ENABLE;
561 desc->req_id = port->req_id;
562 desc->operation = op;
567 desc->ncookies = err;
569 /* This has to be a non-SMP write barrier because we are writing
570 * to memory which is shared with the peer LDOM.
573 desc->hdr.state = VIO_DESC_READY;
575 err = __vdc_tx_trigger(port);
578 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
579 spin_unlock_irqrestore(&port->vio.lock, flags);
581 wait_for_completion(&comp.com);
584 port->vio.cmp = NULL;
585 spin_unlock_irqrestore(&port->vio.lock, flags);
588 if (map_perm & LDC_MAP_W)
589 memcpy(buf, req_buf, len);
596 static int __devinit vdc_alloc_tx_ring(struct vdc_port *port)
598 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
599 unsigned long len, entry_size;
603 entry_size = sizeof(struct vio_disk_desc) +
604 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
605 len = (VDC_TX_RING_SIZE * entry_size);
607 ncookies = VIO_MAX_RING_COOKIES;
608 dring = ldc_alloc_exp_dring(port->vio.lp, len,
609 dr->cookies, &ncookies,
614 return PTR_ERR(dring);
617 dr->entry_size = entry_size;
618 dr->num_entries = VDC_TX_RING_SIZE;
619 dr->prod = dr->cons = 0;
620 dr->pending = VDC_TX_RING_SIZE;
621 dr->ncookies = ncookies;
626 static void vdc_free_tx_ring(struct vdc_port *port)
628 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
631 ldc_free_exp_dring(port->vio.lp, dr->base,
632 (dr->entry_size * dr->num_entries),
633 dr->cookies, dr->ncookies);
642 static int probe_disk(struct vdc_port *port)
644 struct vio_completion comp;
645 struct request_queue *q;
649 init_completion(&comp.com);
651 comp.waiting_for = WAITING_FOR_LINK_UP;
652 port->vio.cmp = ∁
654 vio_port_up(&port->vio);
656 wait_for_completion(&comp.com);
660 err = generic_request(port, VD_OP_GET_VTOC,
661 &port->label, sizeof(port->label));
663 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
667 err = generic_request(port, VD_OP_GET_DISKGEOM,
668 &port->geom, sizeof(port->geom));
670 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
675 port->vdisk_size = ((u64)port->geom.num_cyl *
676 (u64)port->geom.num_hd *
677 (u64)port->geom.num_sec);
679 q = blk_init_queue(do_vdc_request, &port->vio.lock);
681 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
685 g = alloc_disk(1 << PARTITION_SHIFT);
687 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
689 blk_cleanup_queue(q);
695 blk_queue_max_hw_segments(q, port->ring_cookies);
696 blk_queue_max_phys_segments(q, port->ring_cookies);
697 blk_queue_max_sectors(q, port->max_xfer_size);
698 g->major = vdc_major;
699 g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
700 strcpy(g->disk_name, port->disk_name);
704 g->private_data = port;
705 g->driverfs_dev = &port->vio.vdev->dev;
707 set_capacity(g, port->vdisk_size);
709 printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
711 port->vdisk_size, (port->vdisk_size >> (20 - 9)));
718 static struct ldc_channel_config vdc_ldc_cfg = {
721 .mode = LDC_MODE_UNRELIABLE,
724 static struct vio_driver_ops vdc_vio_ops = {
725 .send_attr = vdc_send_attr,
726 .handle_attr = vdc_handle_attr,
727 .handshake_complete = vdc_handshake_complete,
730 static void __devinit print_version(void)
732 static int version_printed;
734 if (version_printed++ == 0)
735 printk(KERN_INFO "%s", version);
738 static int __devinit vdc_port_probe(struct vio_dev *vdev,
739 const struct vio_device_id *id)
741 struct mdesc_handle *hp;
742 struct vdc_port *port;
750 if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
751 printk(KERN_ERR PFX "Port id [%llu] too large.\n",
753 goto err_out_release_mdesc;
756 port = kzalloc(sizeof(*port), GFP_KERNEL);
759 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
760 goto err_out_release_mdesc;
763 if (vdev->dev_no >= 26)
764 snprintf(port->disk_name, sizeof(port->disk_name),
766 'a' + ((int)vdev->dev_no / 26) - 1,
767 'a' + ((int)vdev->dev_no % 26));
769 snprintf(port->disk_name, sizeof(port->disk_name),
770 VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
772 err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
773 vdc_versions, ARRAY_SIZE(vdc_versions),
774 &vdc_vio_ops, port->disk_name);
776 goto err_out_free_port;
778 port->vdisk_block_size = 512;
779 port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
780 port->ring_cookies = ((port->max_xfer_size *
781 port->vdisk_block_size) / PAGE_SIZE) + 2;
783 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
785 goto err_out_free_port;
787 err = vdc_alloc_tx_ring(port);
789 goto err_out_free_ldc;
791 err = probe_disk(port);
793 goto err_out_free_tx_ring;
795 dev_set_drvdata(&vdev->dev, port);
801 err_out_free_tx_ring:
802 vdc_free_tx_ring(port);
805 vio_ldc_free(&port->vio);
810 err_out_release_mdesc:
815 static int vdc_port_remove(struct vio_dev *vdev)
817 struct vdc_port *port = dev_get_drvdata(&vdev->dev);
820 del_timer_sync(&port->vio.timer);
822 vdc_free_tx_ring(port);
823 vio_ldc_free(&port->vio);
825 dev_set_drvdata(&vdev->dev, NULL);
832 static const struct vio_device_id vdc_port_match[] = {
838 MODULE_DEVICE_TABLE(vio, vdc_port_match);
840 static struct vio_driver vdc_port_driver = {
841 .id_table = vdc_port_match,
842 .probe = vdc_port_probe,
843 .remove = vdc_port_remove,
846 .owner = THIS_MODULE,
850 static int __init vdc_init(void)
854 err = register_blkdev(0, VDCBLK_NAME);
860 err = vio_register_driver(&vdc_port_driver);
862 goto out_unregister_blkdev;
866 out_unregister_blkdev:
867 unregister_blkdev(vdc_major, VDCBLK_NAME);
874 static void __exit vdc_exit(void)
876 vio_unregister_driver(&vdc_port_driver);
877 unregister_blkdev(vdc_major, VDCBLK_NAME);
880 module_init(vdc_init);
881 module_exit(vdc_exit);