xref: /openbmc/linux/drivers/block/aoe/aoeblk.c (revision d0b73b48)
1 /* Copyright (c) 2012 Coraid, Inc.  See COPYING for GPL terms. */
2 /*
3  * aoeblk.c
4  * block device routines
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/hdreg.h>
9 #include <linux/blkdev.h>
10 #include <linux/backing-dev.h>
11 #include <linux/fs.h>
12 #include <linux/ioctl.h>
13 #include <linux/slab.h>
14 #include <linux/ratelimit.h>
15 #include <linux/genhd.h>
16 #include <linux/netdevice.h>
17 #include <linux/mutex.h>
18 #include <linux/export.h>
19 #include <linux/moduleparam.h>
20 #include <scsi/sg.h>
21 #include "aoe.h"
22 
23 static DEFINE_MUTEX(aoeblk_mutex);
24 static struct kmem_cache *buf_pool_cache;
25 
26 /* GPFS needs a larger value than the default. */
27 static int aoe_maxsectors;
28 module_param(aoe_maxsectors, int, 0644);
29 MODULE_PARM_DESC(aoe_maxsectors,
30 	"When nonzero, set the maximum number of sectors per I/O request");
31 
32 static ssize_t aoedisk_show_state(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 
38 	return snprintf(page, PAGE_SIZE,
39 			"%s%s\n",
40 			(d->flags & DEVFL_UP) ? "up" : "down",
41 			(d->flags & DEVFL_KICKME) ? ",kickme" :
42 			(d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
43 	/* I'd rather see nopen exported so we can ditch closewait */
44 }
45 static ssize_t aoedisk_show_mac(struct device *dev,
46 				struct device_attribute *attr, char *page)
47 {
48 	struct gendisk *disk = dev_to_disk(dev);
49 	struct aoedev *d = disk->private_data;
50 	struct aoetgt *t = d->targets[0];
51 
52 	if (t == NULL)
53 		return snprintf(page, PAGE_SIZE, "none\n");
54 	return snprintf(page, PAGE_SIZE, "%pm\n", t->addr);
55 }
56 static ssize_t aoedisk_show_netif(struct device *dev,
57 				  struct device_attribute *attr, char *page)
58 {
59 	struct gendisk *disk = dev_to_disk(dev);
60 	struct aoedev *d = disk->private_data;
61 	struct net_device *nds[8], **nd, **nnd, **ne;
62 	struct aoetgt **t, **te;
63 	struct aoeif *ifp, *e;
64 	char *p;
65 
66 	memset(nds, 0, sizeof nds);
67 	nd = nds;
68 	ne = nd + ARRAY_SIZE(nds);
69 	t = d->targets;
70 	te = t + d->ntargets;
71 	for (; t < te && *t; t++) {
72 		ifp = (*t)->ifs;
73 		e = ifp + NAOEIFS;
74 		for (; ifp < e && ifp->nd; ifp++) {
75 			for (nnd = nds; nnd < nd; nnd++)
76 				if (*nnd == ifp->nd)
77 					break;
78 			if (nnd == nd && nd != ne)
79 				*nd++ = ifp->nd;
80 		}
81 	}
82 
83 	ne = nd;
84 	nd = nds;
85 	if (*nd == NULL)
86 		return snprintf(page, PAGE_SIZE, "none\n");
87 	for (p = page; nd < ne; nd++)
88 		p += snprintf(p, PAGE_SIZE - (p-page), "%s%s",
89 			p == page ? "" : ",", (*nd)->name);
90 	p += snprintf(p, PAGE_SIZE - (p-page), "\n");
91 	return p-page;
92 }
93 /* firmware version */
94 static ssize_t aoedisk_show_fwver(struct device *dev,
95 				  struct device_attribute *attr, char *page)
96 {
97 	struct gendisk *disk = dev_to_disk(dev);
98 	struct aoedev *d = disk->private_data;
99 
100 	return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
101 }
102 static ssize_t aoedisk_show_payload(struct device *dev,
103 				    struct device_attribute *attr, char *page)
104 {
105 	struct gendisk *disk = dev_to_disk(dev);
106 	struct aoedev *d = disk->private_data;
107 
108 	return snprintf(page, PAGE_SIZE, "%lu\n", d->maxbcnt);
109 }
110 
111 static DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL);
112 static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL);
113 static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL);
114 static struct device_attribute dev_attr_firmware_version = {
115 	.attr = { .name = "firmware-version", .mode = S_IRUGO },
116 	.show = aoedisk_show_fwver,
117 };
118 static DEVICE_ATTR(payload, S_IRUGO, aoedisk_show_payload, NULL);
119 
120 static struct attribute *aoe_attrs[] = {
121 	&dev_attr_state.attr,
122 	&dev_attr_mac.attr,
123 	&dev_attr_netif.attr,
124 	&dev_attr_firmware_version.attr,
125 	&dev_attr_payload.attr,
126 	NULL,
127 };
128 
129 static const struct attribute_group attr_group = {
130 	.attrs = aoe_attrs,
131 };
132 
133 static int
134 aoedisk_add_sysfs(struct aoedev *d)
135 {
136 	return sysfs_create_group(&disk_to_dev(d->gd)->kobj, &attr_group);
137 }
138 void
139 aoedisk_rm_sysfs(struct aoedev *d)
140 {
141 	sysfs_remove_group(&disk_to_dev(d->gd)->kobj, &attr_group);
142 }
143 
144 static int
145 aoeblk_open(struct block_device *bdev, fmode_t mode)
146 {
147 	struct aoedev *d = bdev->bd_disk->private_data;
148 	ulong flags;
149 
150 	if (!virt_addr_valid(d)) {
151 		pr_crit("aoe: invalid device pointer in %s\n",
152 			__func__);
153 		WARN_ON(1);
154 		return -ENODEV;
155 	}
156 	if (!(d->flags & DEVFL_UP) || d->flags & DEVFL_TKILL)
157 		return -ENODEV;
158 
159 	mutex_lock(&aoeblk_mutex);
160 	spin_lock_irqsave(&d->lock, flags);
161 	if (d->flags & DEVFL_UP && !(d->flags & DEVFL_TKILL)) {
162 		d->nopen++;
163 		spin_unlock_irqrestore(&d->lock, flags);
164 		mutex_unlock(&aoeblk_mutex);
165 		return 0;
166 	}
167 	spin_unlock_irqrestore(&d->lock, flags);
168 	mutex_unlock(&aoeblk_mutex);
169 	return -ENODEV;
170 }
171 
172 static int
173 aoeblk_release(struct gendisk *disk, fmode_t mode)
174 {
175 	struct aoedev *d = disk->private_data;
176 	ulong flags;
177 
178 	spin_lock_irqsave(&d->lock, flags);
179 
180 	if (--d->nopen == 0) {
181 		spin_unlock_irqrestore(&d->lock, flags);
182 		aoecmd_cfg(d->aoemajor, d->aoeminor);
183 		return 0;
184 	}
185 	spin_unlock_irqrestore(&d->lock, flags);
186 
187 	return 0;
188 }
189 
190 static void
191 aoeblk_request(struct request_queue *q)
192 {
193 	struct aoedev *d;
194 	struct request *rq;
195 
196 	d = q->queuedata;
197 	if ((d->flags & DEVFL_UP) == 0) {
198 		pr_info_ratelimited("aoe: device %ld.%d is not up\n",
199 			d->aoemajor, d->aoeminor);
200 		while ((rq = blk_peek_request(q))) {
201 			blk_start_request(rq);
202 			aoe_end_request(d, rq, 1);
203 		}
204 		return;
205 	}
206 	aoecmd_work(d);
207 }
208 
209 static int
210 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
211 {
212 	struct aoedev *d = bdev->bd_disk->private_data;
213 
214 	if ((d->flags & DEVFL_UP) == 0) {
215 		printk(KERN_ERR "aoe: disk not up\n");
216 		return -ENODEV;
217 	}
218 
219 	geo->cylinders = d->geo.cylinders;
220 	geo->heads = d->geo.heads;
221 	geo->sectors = d->geo.sectors;
222 	return 0;
223 }
224 
225 static int
226 aoeblk_ioctl(struct block_device *bdev, fmode_t mode, uint cmd, ulong arg)
227 {
228 	struct aoedev *d;
229 
230 	if (!arg)
231 		return -EINVAL;
232 
233 	d = bdev->bd_disk->private_data;
234 	if ((d->flags & DEVFL_UP) == 0) {
235 		pr_err("aoe: disk not up\n");
236 		return -ENODEV;
237 	}
238 
239 	if (cmd == HDIO_GET_IDENTITY) {
240 		if (!copy_to_user((void __user *) arg, &d->ident,
241 			sizeof(d->ident)))
242 			return 0;
243 		return -EFAULT;
244 	}
245 
246 	/* udev calls scsi_id, which uses SG_IO, resulting in noise */
247 	if (cmd != SG_IO)
248 		pr_info("aoe: unknown ioctl 0x%x\n", cmd);
249 
250 	return -ENOTTY;
251 }
252 
253 static const struct block_device_operations aoe_bdops = {
254 	.open = aoeblk_open,
255 	.release = aoeblk_release,
256 	.ioctl = aoeblk_ioctl,
257 	.getgeo = aoeblk_getgeo,
258 	.owner = THIS_MODULE,
259 };
260 
261 /* alloc_disk and add_disk can sleep */
262 void
263 aoeblk_gdalloc(void *vp)
264 {
265 	struct aoedev *d = vp;
266 	struct gendisk *gd;
267 	mempool_t *mp;
268 	struct request_queue *q;
269 	enum { KB = 1024, MB = KB * KB, READ_AHEAD = 2 * MB, };
270 	ulong flags;
271 	int late = 0;
272 
273 	spin_lock_irqsave(&d->lock, flags);
274 	if (d->flags & DEVFL_GDALLOC
275 	&& !(d->flags & DEVFL_TKILL)
276 	&& !(d->flags & DEVFL_GD_NOW))
277 		d->flags |= DEVFL_GD_NOW;
278 	else
279 		late = 1;
280 	spin_unlock_irqrestore(&d->lock, flags);
281 	if (late)
282 		return;
283 
284 	gd = alloc_disk(AOE_PARTITIONS);
285 	if (gd == NULL) {
286 		pr_err("aoe: cannot allocate disk structure for %ld.%d\n",
287 			d->aoemajor, d->aoeminor);
288 		goto err;
289 	}
290 
291 	mp = mempool_create(MIN_BUFS, mempool_alloc_slab, mempool_free_slab,
292 		buf_pool_cache);
293 	if (mp == NULL) {
294 		printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
295 			d->aoemajor, d->aoeminor);
296 		goto err_disk;
297 	}
298 	q = blk_init_queue(aoeblk_request, &d->lock);
299 	if (q == NULL) {
300 		pr_err("aoe: cannot allocate block queue for %ld.%d\n",
301 			d->aoemajor, d->aoeminor);
302 		goto err_mempool;
303 	}
304 
305 	spin_lock_irqsave(&d->lock, flags);
306 	WARN_ON(!(d->flags & DEVFL_GD_NOW));
307 	WARN_ON(!(d->flags & DEVFL_GDALLOC));
308 	WARN_ON(d->flags & DEVFL_TKILL);
309 	WARN_ON(d->gd);
310 	WARN_ON(d->flags & DEVFL_UP);
311 	blk_queue_max_hw_sectors(q, BLK_DEF_MAX_SECTORS);
312 	q->backing_dev_info.name = "aoe";
313 	q->backing_dev_info.ra_pages = READ_AHEAD / PAGE_CACHE_SIZE;
314 	d->bufpool = mp;
315 	d->blkq = gd->queue = q;
316 	q->queuedata = d;
317 	d->gd = gd;
318 	if (aoe_maxsectors)
319 		blk_queue_max_hw_sectors(q, aoe_maxsectors);
320 	gd->major = AOE_MAJOR;
321 	gd->first_minor = d->sysminor;
322 	gd->fops = &aoe_bdops;
323 	gd->private_data = d;
324 	set_capacity(gd, d->ssize);
325 	snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
326 		d->aoemajor, d->aoeminor);
327 
328 	d->flags &= ~DEVFL_GDALLOC;
329 	d->flags |= DEVFL_UP;
330 
331 	spin_unlock_irqrestore(&d->lock, flags);
332 
333 	add_disk(gd);
334 	aoedisk_add_sysfs(d);
335 
336 	spin_lock_irqsave(&d->lock, flags);
337 	WARN_ON(!(d->flags & DEVFL_GD_NOW));
338 	d->flags &= ~DEVFL_GD_NOW;
339 	spin_unlock_irqrestore(&d->lock, flags);
340 	return;
341 
342 err_mempool:
343 	mempool_destroy(mp);
344 err_disk:
345 	put_disk(gd);
346 err:
347 	spin_lock_irqsave(&d->lock, flags);
348 	d->flags &= ~DEVFL_GD_NOW;
349 	schedule_work(&d->work);
350 	spin_unlock_irqrestore(&d->lock, flags);
351 }
352 
353 void
354 aoeblk_exit(void)
355 {
356 	kmem_cache_destroy(buf_pool_cache);
357 }
358 
359 int __init
360 aoeblk_init(void)
361 {
362 	buf_pool_cache = kmem_cache_create("aoe_bufs",
363 					   sizeof(struct buf),
364 					   0, 0, NULL);
365 	if (buf_pool_cache == NULL)
366 		return -ENOMEM;
367 
368 	return 0;
369 }
370 
371