1 /* sunvdc.c: Sun LDOM Virtual Disk Client.
3 * Copyright (C) 2007 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[%lu]\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[%lx] disk_size[%lu] disk_type[%x] "
168 "xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\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_request(struct request *req, int uptodate, int num_sectors)
217 if (end_that_request_first(req, uptodate, num_sectors))
219 add_disk_randomness(req->rq_disk);
220 end_that_request_last(req, uptodate);
223 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
226 struct vio_disk_desc *desc = vio_dring_entry(dr, index);
227 struct vdc_req_entry *rqe = &port->rq_arr[index];
230 if (unlikely(desc->hdr.state != VIO_DESC_DONE))
233 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
234 desc->hdr.state = VIO_DESC_FREE;
235 dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
239 vdc_end_special(port, desc);
245 vdc_end_request(req, !desc->status, desc->size >> 9);
247 if (blk_queue_stopped(port->disk->queue))
248 blk_start_queue(port->disk->queue);
251 static int vdc_ack(struct vdc_port *port, void *msgbuf)
253 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
254 struct vio_dring_data *pkt = msgbuf;
256 if (unlikely(pkt->dring_ident != dr->ident ||
257 pkt->start_idx != pkt->end_idx ||
258 pkt->start_idx >= VDC_TX_RING_SIZE))
261 vdc_end_one(port, dr, pkt->start_idx);
266 static int vdc_nack(struct vdc_port *port, void *msgbuf)
268 /* XXX Implement me XXX */
272 static void vdc_event(void *arg, int event)
274 struct vdc_port *port = arg;
275 struct vio_driver_state *vio = &port->vio;
279 spin_lock_irqsave(&vio->lock, flags);
281 if (unlikely(event == LDC_EVENT_RESET ||
282 event == LDC_EVENT_UP)) {
283 vio_link_state_change(vio, event);
284 spin_unlock_irqrestore(&vio->lock, flags);
288 if (unlikely(event != LDC_EVENT_DATA_READY)) {
289 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
290 spin_unlock_irqrestore(&vio->lock, flags);
297 struct vio_msg_tag tag;
301 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
302 if (unlikely(err < 0)) {
303 if (err == -ECONNRESET)
309 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
312 msgbuf.tag.stype_env,
314 err = vio_validate_sid(vio, &msgbuf.tag);
318 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
319 if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
320 err = vdc_ack(port, &msgbuf);
321 else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
322 err = vdc_nack(port, &msgbuf);
324 err = vdc_handle_unknown(port, &msgbuf);
325 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
326 err = vio_control_pkt_engine(vio, &msgbuf);
328 err = vdc_handle_unknown(port, &msgbuf);
334 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
335 spin_unlock_irqrestore(&vio->lock, flags);
338 static int __vdc_tx_trigger(struct vdc_port *port)
340 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
341 struct vio_dring_data hdr = {
343 .type = VIO_TYPE_DATA,
344 .stype = VIO_SUBTYPE_INFO,
345 .stype_env = VIO_DRING_DATA,
346 .sid = vio_send_sid(&port->vio),
348 .dring_ident = dr->ident,
349 .start_idx = dr->prod,
354 hdr.seq = dr->snd_nxt;
357 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
363 if ((delay <<= 1) > 128)
365 } while (err == -EAGAIN);
370 static int __send_request(struct request *req)
372 struct vdc_port *port = req->rq_disk->private_data;
373 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
374 struct scatterlist sg[port->ring_cookies];
375 struct vdc_req_entry *rqe;
376 struct vio_disk_desc *desc;
377 unsigned int map_perm;
382 map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
384 if (rq_data_dir(req) == READ) {
385 map_perm |= LDC_MAP_W;
388 map_perm |= LDC_MAP_R;
392 sg_init_table(sg, port->ring_cookies);
393 nsg = blk_rq_map_sg(req->q, req, sg);
396 for (i = 0; i < nsg; i++)
399 if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
400 blk_stop_queue(port->disk->queue);
405 desc = vio_dring_cur(dr);
407 err = ldc_map_sg(port->vio.lp, sg, nsg,
408 desc->cookies, port->ring_cookies,
411 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
415 rqe = &port->rq_arr[dr->prod];
418 desc->hdr.ack = VIO_ACK_ENABLE;
419 desc->req_id = port->req_id;
420 desc->operation = op;
421 if (port->vdisk_type == VD_DISK_TYPE_DISK) {
427 desc->offset = (req->sector << 9) / port->vdisk_block_size;
429 desc->ncookies = err;
431 /* This has to be a non-SMP write barrier because we are writing
432 * to memory which is shared with the peer LDOM.
435 desc->hdr.state = VIO_DESC_READY;
437 err = __vdc_tx_trigger(port);
439 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
442 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
449 static void do_vdc_request(struct request_queue *q)
452 struct request *req = elv_next_request(q);
457 blkdev_dequeue_request(req);
458 if (__send_request(req) < 0)
459 vdc_end_request(req, 0, req->hard_nr_sectors);
463 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
465 struct vio_dring_state *dr;
466 struct vio_completion comp;
467 struct vio_disk_desc *desc;
468 unsigned int map_perm;
473 if (!(((u64)1 << ((u64)op - 1)) & port->operations))
488 op_len = sizeof(u32);
489 map_perm = LDC_MAP_W;
493 op_len = sizeof(u32);
494 map_perm = LDC_MAP_R;
498 op_len = sizeof(struct vio_disk_vtoc);
499 map_perm = LDC_MAP_W;
503 op_len = sizeof(struct vio_disk_vtoc);
504 map_perm = LDC_MAP_R;
507 case VD_OP_GET_DISKGEOM:
508 op_len = sizeof(struct vio_disk_geom);
509 map_perm = LDC_MAP_W;
512 case VD_OP_SET_DISKGEOM:
513 op_len = sizeof(struct vio_disk_geom);
514 map_perm = LDC_MAP_R;
519 map_perm = LDC_MAP_RW;
522 case VD_OP_GET_DEVID:
523 op_len = sizeof(struct vio_disk_devid);
524 map_perm = LDC_MAP_W;
533 map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
535 op_len = (op_len + 7) & ~7;
536 req_buf = kzalloc(op_len, GFP_KERNEL);
543 if (map_perm & LDC_MAP_R)
544 memcpy(req_buf, buf, len);
546 spin_lock_irqsave(&port->vio.lock, flags);
548 dr = &port->vio.drings[VIO_DRIVER_TX_RING];
550 /* XXX If we want to use this code generically we have to
551 * XXX handle TX ring exhaustion etc.
553 desc = vio_dring_cur(dr);
555 err = ldc_map_single(port->vio.lp, req_buf, op_len,
556 desc->cookies, port->ring_cookies,
559 spin_unlock_irqrestore(&port->vio.lock, flags);
564 init_completion(&comp.com);
565 comp.waiting_for = WAITING_FOR_GEN_CMD;
566 port->vio.cmp = ∁
568 desc->hdr.ack = VIO_ACK_ENABLE;
569 desc->req_id = port->req_id;
570 desc->operation = op;
575 desc->ncookies = err;
577 /* This has to be a non-SMP write barrier because we are writing
578 * to memory which is shared with the peer LDOM.
581 desc->hdr.state = VIO_DESC_READY;
583 err = __vdc_tx_trigger(port);
586 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
587 spin_unlock_irqrestore(&port->vio.lock, flags);
589 wait_for_completion(&comp.com);
592 port->vio.cmp = NULL;
593 spin_unlock_irqrestore(&port->vio.lock, flags);
596 if (map_perm & LDC_MAP_W)
597 memcpy(buf, req_buf, len);
604 static int __devinit vdc_alloc_tx_ring(struct vdc_port *port)
606 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
607 unsigned long len, entry_size;
611 entry_size = sizeof(struct vio_disk_desc) +
612 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
613 len = (VDC_TX_RING_SIZE * entry_size);
615 ncookies = VIO_MAX_RING_COOKIES;
616 dring = ldc_alloc_exp_dring(port->vio.lp, len,
617 dr->cookies, &ncookies,
622 return PTR_ERR(dring);
625 dr->entry_size = entry_size;
626 dr->num_entries = VDC_TX_RING_SIZE;
627 dr->prod = dr->cons = 0;
628 dr->pending = VDC_TX_RING_SIZE;
629 dr->ncookies = ncookies;
634 static void vdc_free_tx_ring(struct vdc_port *port)
636 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
639 ldc_free_exp_dring(port->vio.lp, dr->base,
640 (dr->entry_size * dr->num_entries),
641 dr->cookies, dr->ncookies);
650 static int probe_disk(struct vdc_port *port)
652 struct vio_completion comp;
653 struct request_queue *q;
657 init_completion(&comp.com);
659 comp.waiting_for = WAITING_FOR_LINK_UP;
660 port->vio.cmp = ∁
662 vio_port_up(&port->vio);
664 wait_for_completion(&comp.com);
668 err = generic_request(port, VD_OP_GET_VTOC,
669 &port->label, sizeof(port->label));
671 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
675 err = generic_request(port, VD_OP_GET_DISKGEOM,
676 &port->geom, sizeof(port->geom));
678 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
683 port->vdisk_size = ((u64)port->geom.num_cyl *
684 (u64)port->geom.num_hd *
685 (u64)port->geom.num_sec);
687 q = blk_init_queue(do_vdc_request, &port->vio.lock);
689 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
693 g = alloc_disk(1 << PARTITION_SHIFT);
695 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
697 blk_cleanup_queue(q);
703 blk_queue_max_hw_segments(q, port->ring_cookies);
704 blk_queue_max_phys_segments(q, port->ring_cookies);
705 blk_queue_max_sectors(q, port->max_xfer_size);
706 g->major = vdc_major;
707 g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
708 strcpy(g->disk_name, port->disk_name);
712 g->private_data = port;
713 g->driverfs_dev = &port->vio.vdev->dev;
715 set_capacity(g, port->vdisk_size);
717 printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
719 port->vdisk_size, (port->vdisk_size >> (20 - 9)));
726 static struct ldc_channel_config vdc_ldc_cfg = {
729 .mode = LDC_MODE_UNRELIABLE,
732 static struct vio_driver_ops vdc_vio_ops = {
733 .send_attr = vdc_send_attr,
734 .handle_attr = vdc_handle_attr,
735 .handshake_complete = vdc_handshake_complete,
738 static void print_version(void)
740 static int version_printed;
742 if (version_printed++ == 0)
743 printk(KERN_INFO "%s", version);
746 static int __devinit vdc_port_probe(struct vio_dev *vdev,
747 const struct vio_device_id *id)
749 struct mdesc_handle *hp;
750 struct vdc_port *port;
758 if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
759 printk(KERN_ERR PFX "Port id [%lu] too large.\n",
761 goto err_out_release_mdesc;
764 port = kzalloc(sizeof(*port), GFP_KERNEL);
767 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
768 goto err_out_release_mdesc;
771 if (vdev->dev_no >= 26)
772 snprintf(port->disk_name, sizeof(port->disk_name),
774 'a' + ((int)vdev->dev_no / 26) - 1,
775 'a' + ((int)vdev->dev_no % 26));
777 snprintf(port->disk_name, sizeof(port->disk_name),
778 VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
780 err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
781 vdc_versions, ARRAY_SIZE(vdc_versions),
782 &vdc_vio_ops, port->disk_name);
784 goto err_out_free_port;
786 port->vdisk_block_size = 512;
787 port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
788 port->ring_cookies = ((port->max_xfer_size *
789 port->vdisk_block_size) / PAGE_SIZE) + 2;
791 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
793 goto err_out_free_port;
795 err = vdc_alloc_tx_ring(port);
797 goto err_out_free_ldc;
799 err = probe_disk(port);
801 goto err_out_free_tx_ring;
803 dev_set_drvdata(&vdev->dev, port);
809 err_out_free_tx_ring:
810 vdc_free_tx_ring(port);
813 vio_ldc_free(&port->vio);
818 err_out_release_mdesc:
823 static int vdc_port_remove(struct vio_dev *vdev)
825 struct vdc_port *port = dev_get_drvdata(&vdev->dev);
828 del_timer_sync(&port->vio.timer);
830 vdc_free_tx_ring(port);
831 vio_ldc_free(&port->vio);
833 dev_set_drvdata(&vdev->dev, NULL);
840 static struct vio_device_id vdc_port_match[] = {
846 MODULE_DEVICE_TABLE(vio, vdc_port_match);
848 static struct vio_driver vdc_port_driver = {
849 .id_table = vdc_port_match,
850 .probe = vdc_port_probe,
851 .remove = vdc_port_remove,
854 .owner = THIS_MODULE,
858 static int __init vdc_init(void)
862 err = register_blkdev(0, VDCBLK_NAME);
868 err = vio_register_driver(&vdc_port_driver);
870 goto out_unregister_blkdev;
874 out_unregister_blkdev:
875 unregister_blkdev(vdc_major, VDCBLK_NAME);
882 static void __exit vdc_exit(void)
884 vio_unregister_driver(&vdc_port_driver);
885 unregister_blkdev(vdc_major, VDCBLK_NAME);
888 module_init(vdc_init);
889 module_exit(vdc_exit);