aoeblk.c revision 5a0e3ad6af8660be21ca98a971cd00f331318c05
1/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
2/*
3 * aoeblk.c
4 * block device routines
5 */
6
7#include <linux/hdreg.h>
8#include <linux/blkdev.h>
9#include <linux/backing-dev.h>
10#include <linux/fs.h>
11#include <linux/ioctl.h>
12#include <linux/slab.h>
13#include <linux/genhd.h>
14#include <linux/netdevice.h>
15#include "aoe.h"
16
17static struct kmem_cache *buf_pool_cache;
18
19static ssize_t aoedisk_show_state(struct device *dev,
20				  struct device_attribute *attr, char *page)
21{
22	struct gendisk *disk = dev_to_disk(dev);
23	struct aoedev *d = disk->private_data;
24
25	return snprintf(page, PAGE_SIZE,
26			"%s%s\n",
27			(d->flags & DEVFL_UP) ? "up" : "down",
28			(d->flags & DEVFL_KICKME) ? ",kickme" :
29			(d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
30	/* I'd rather see nopen exported so we can ditch closewait */
31}
32static ssize_t aoedisk_show_mac(struct device *dev,
33				struct device_attribute *attr, char *page)
34{
35	struct gendisk *disk = dev_to_disk(dev);
36	struct aoedev *d = disk->private_data;
37	struct aoetgt *t = d->targets[0];
38
39	if (t == NULL)
40		return snprintf(page, PAGE_SIZE, "none\n");
41	return snprintf(page, PAGE_SIZE, "%pm\n", t->addr);
42}
43static ssize_t aoedisk_show_netif(struct device *dev,
44				  struct device_attribute *attr, char *page)
45{
46	struct gendisk *disk = dev_to_disk(dev);
47	struct aoedev *d = disk->private_data;
48	struct net_device *nds[8], **nd, **nnd, **ne;
49	struct aoetgt **t, **te;
50	struct aoeif *ifp, *e;
51	char *p;
52
53	memset(nds, 0, sizeof nds);
54	nd = nds;
55	ne = nd + ARRAY_SIZE(nds);
56	t = d->targets;
57	te = t + NTARGETS;
58	for (; t < te && *t; t++) {
59		ifp = (*t)->ifs;
60		e = ifp + NAOEIFS;
61		for (; ifp < e && ifp->nd; ifp++) {
62			for (nnd = nds; nnd < nd; nnd++)
63				if (*nnd == ifp->nd)
64					break;
65			if (nnd == nd && nd != ne)
66				*nd++ = ifp->nd;
67		}
68	}
69
70	ne = nd;
71	nd = nds;
72	if (*nd == NULL)
73		return snprintf(page, PAGE_SIZE, "none\n");
74	for (p = page; nd < ne; nd++)
75		p += snprintf(p, PAGE_SIZE - (p-page), "%s%s",
76			p == page ? "" : ",", (*nd)->name);
77	p += snprintf(p, PAGE_SIZE - (p-page), "\n");
78	return p-page;
79}
80/* firmware version */
81static ssize_t aoedisk_show_fwver(struct device *dev,
82				  struct device_attribute *attr, char *page)
83{
84	struct gendisk *disk = dev_to_disk(dev);
85	struct aoedev *d = disk->private_data;
86
87	return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
88}
89
90static DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL);
91static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL);
92static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL);
93static struct device_attribute dev_attr_firmware_version = {
94	.attr = { .name = "firmware-version", .mode = S_IRUGO },
95	.show = aoedisk_show_fwver,
96};
97
98static struct attribute *aoe_attrs[] = {
99	&dev_attr_state.attr,
100	&dev_attr_mac.attr,
101	&dev_attr_netif.attr,
102	&dev_attr_firmware_version.attr,
103	NULL,
104};
105
106static const struct attribute_group attr_group = {
107	.attrs = aoe_attrs,
108};
109
110static int
111aoedisk_add_sysfs(struct aoedev *d)
112{
113	return sysfs_create_group(&disk_to_dev(d->gd)->kobj, &attr_group);
114}
115void
116aoedisk_rm_sysfs(struct aoedev *d)
117{
118	sysfs_remove_group(&disk_to_dev(d->gd)->kobj, &attr_group);
119}
120
121static int
122aoeblk_open(struct block_device *bdev, fmode_t mode)
123{
124	struct aoedev *d = bdev->bd_disk->private_data;
125	ulong flags;
126
127	spin_lock_irqsave(&d->lock, flags);
128	if (d->flags & DEVFL_UP) {
129		d->nopen++;
130		spin_unlock_irqrestore(&d->lock, flags);
131		return 0;
132	}
133	spin_unlock_irqrestore(&d->lock, flags);
134	return -ENODEV;
135}
136
137static int
138aoeblk_release(struct gendisk *disk, fmode_t mode)
139{
140	struct aoedev *d = disk->private_data;
141	ulong flags;
142
143	spin_lock_irqsave(&d->lock, flags);
144
145	if (--d->nopen == 0) {
146		spin_unlock_irqrestore(&d->lock, flags);
147		aoecmd_cfg(d->aoemajor, d->aoeminor);
148		return 0;
149	}
150	spin_unlock_irqrestore(&d->lock, flags);
151
152	return 0;
153}
154
155static int
156aoeblk_make_request(struct request_queue *q, struct bio *bio)
157{
158	struct sk_buff_head queue;
159	struct aoedev *d;
160	struct buf *buf;
161	ulong flags;
162
163	blk_queue_bounce(q, &bio);
164
165	if (bio == NULL) {
166		printk(KERN_ERR "aoe: bio is NULL\n");
167		BUG();
168		return 0;
169	}
170	d = bio->bi_bdev->bd_disk->private_data;
171	if (d == NULL) {
172		printk(KERN_ERR "aoe: bd_disk->private_data is NULL\n");
173		BUG();
174		bio_endio(bio, -ENXIO);
175		return 0;
176	} else if (bio_rw_flagged(bio, BIO_RW_BARRIER)) {
177		bio_endio(bio, -EOPNOTSUPP);
178		return 0;
179	} else if (bio->bi_io_vec == NULL) {
180		printk(KERN_ERR "aoe: bi_io_vec is NULL\n");
181		BUG();
182		bio_endio(bio, -ENXIO);
183		return 0;
184	}
185	buf = mempool_alloc(d->bufpool, GFP_NOIO);
186	if (buf == NULL) {
187		printk(KERN_INFO "aoe: buf allocation failure\n");
188		bio_endio(bio, -ENOMEM);
189		return 0;
190	}
191	memset(buf, 0, sizeof(*buf));
192	INIT_LIST_HEAD(&buf->bufs);
193	buf->stime = jiffies;
194	buf->bio = bio;
195	buf->resid = bio->bi_size;
196	buf->sector = bio->bi_sector;
197	buf->bv = &bio->bi_io_vec[bio->bi_idx];
198	buf->bv_resid = buf->bv->bv_len;
199	WARN_ON(buf->bv_resid == 0);
200	buf->bv_off = buf->bv->bv_offset;
201
202	spin_lock_irqsave(&d->lock, flags);
203
204	if ((d->flags & DEVFL_UP) == 0) {
205		printk(KERN_INFO "aoe: device %ld.%d is not up\n",
206			d->aoemajor, d->aoeminor);
207		spin_unlock_irqrestore(&d->lock, flags);
208		mempool_free(buf, d->bufpool);
209		bio_endio(bio, -ENXIO);
210		return 0;
211	}
212
213	list_add_tail(&buf->bufs, &d->bufq);
214
215	aoecmd_work(d);
216	__skb_queue_head_init(&queue);
217	skb_queue_splice_init(&d->sendq, &queue);
218
219	spin_unlock_irqrestore(&d->lock, flags);
220	aoenet_xmit(&queue);
221
222	return 0;
223}
224
225static int
226aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
227{
228	struct aoedev *d = bdev->bd_disk->private_data;
229
230	if ((d->flags & DEVFL_UP) == 0) {
231		printk(KERN_ERR "aoe: disk not up\n");
232		return -ENODEV;
233	}
234
235	geo->cylinders = d->geo.cylinders;
236	geo->heads = d->geo.heads;
237	geo->sectors = d->geo.sectors;
238	return 0;
239}
240
241static const struct block_device_operations aoe_bdops = {
242	.open = aoeblk_open,
243	.release = aoeblk_release,
244	.getgeo = aoeblk_getgeo,
245	.owner = THIS_MODULE,
246};
247
248/* alloc_disk and add_disk can sleep */
249void
250aoeblk_gdalloc(void *vp)
251{
252	struct aoedev *d = vp;
253	struct gendisk *gd;
254	ulong flags;
255
256	gd = alloc_disk(AOE_PARTITIONS);
257	if (gd == NULL) {
258		printk(KERN_ERR
259			"aoe: cannot allocate disk structure for %ld.%d\n",
260			d->aoemajor, d->aoeminor);
261		goto err;
262	}
263
264	d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache);
265	if (d->bufpool == NULL) {
266		printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
267			d->aoemajor, d->aoeminor);
268		goto err_disk;
269	}
270
271	d->blkq = blk_alloc_queue(GFP_KERNEL);
272	if (!d->blkq)
273		goto err_mempool;
274	blk_queue_make_request(d->blkq, aoeblk_make_request);
275	d->blkq->backing_dev_info.name = "aoe";
276	if (bdi_init(&d->blkq->backing_dev_info))
277		goto err_blkq;
278	spin_lock_irqsave(&d->lock, flags);
279	gd->major = AOE_MAJOR;
280	gd->first_minor = d->sysminor * AOE_PARTITIONS;
281	gd->fops = &aoe_bdops;
282	gd->private_data = d;
283	set_capacity(gd, d->ssize);
284	snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
285		d->aoemajor, d->aoeminor);
286
287	gd->queue = d->blkq;
288	d->gd = gd;
289	d->flags &= ~DEVFL_GDALLOC;
290	d->flags |= DEVFL_UP;
291
292	spin_unlock_irqrestore(&d->lock, flags);
293
294	add_disk(gd);
295	aoedisk_add_sysfs(d);
296	return;
297
298err_blkq:
299	blk_cleanup_queue(d->blkq);
300	d->blkq = NULL;
301err_mempool:
302	mempool_destroy(d->bufpool);
303err_disk:
304	put_disk(gd);
305err:
306	spin_lock_irqsave(&d->lock, flags);
307	d->flags &= ~DEVFL_GDALLOC;
308	spin_unlock_irqrestore(&d->lock, flags);
309}
310
311void
312aoeblk_exit(void)
313{
314	kmem_cache_destroy(buf_pool_cache);
315}
316
317int __init
318aoeblk_init(void)
319{
320	buf_pool_cache = kmem_cache_create("aoe_bufs",
321					   sizeof(struct buf),
322					   0, 0, NULL);
323	if (buf_pool_cache == NULL)
324		return -ENOMEM;
325
326	return 0;
327}
328
329