xref: /openbmc/linux/drivers/block/aoe/aoeblk.c (revision 293d5b43) 
1 /* Copyright (c) 2013 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 <linux/debugfs.h>
21 #include <scsi/sg.h>
22 #include "aoe.h"
23 
24 static DEFINE_MUTEX(aoeblk_mutex);
25 static struct kmem_cache *buf_pool_cache;
26 static struct dentry *aoe_debugfs_dir;
27 
28 /* GPFS needs a larger value than the default. */
29 static int aoe_maxsectors;
30 module_param(aoe_maxsectors, int, 0644);
31 MODULE_PARM_DESC(aoe_maxsectors,
32 	"When nonzero, set the maximum number of sectors per I/O request");
33 
34 static ssize_t aoedisk_show_state(struct device *dev,
35 				  struct device_attribute *attr, char *page)
36 {
37 	struct gendisk *disk = dev_to_disk(dev);
38 	struct aoedev *d = disk->private_data;
39 
40 	return snprintf(page, PAGE_SIZE,
41 			"%s%s\n",
42 			(d->flags & DEVFL_UP) ? "up" : "down",
43 			(d->flags & DEVFL_KICKME) ? ",kickme" :
44 			(d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
45 	/* I'd rather see nopen exported so we can ditch closewait */
46 }
47 static ssize_t aoedisk_show_mac(struct device *dev,
48 				struct device_attribute *attr, char *page)
49 {
50 	struct gendisk *disk = dev_to_disk(dev);
51 	struct aoedev *d = disk->private_data;
52 	struct aoetgt *t = d->targets[0];
53 
54 	if (t == NULL)
55 		return snprintf(page, PAGE_SIZE, "none\n");
56 	return snprintf(page, PAGE_SIZE, "%pm\n", t->addr);
57 }
58 static ssize_t aoedisk_show_netif(struct device *dev,
59 				  struct device_attribute *attr, char *page)
60 {
61 	struct gendisk *disk = dev_to_disk(dev);
62 	struct aoedev *d = disk->private_data;
63 	struct net_device *nds[8], **nd, **nnd, **ne;
64 	struct aoetgt **t, **te;
65 	struct aoeif *ifp, *e;
66 	char *p;
67 
68 	memset(nds, 0, sizeof nds);
69 	nd = nds;
70 	ne = nd + ARRAY_SIZE(nds);
71 	t = d->targets;
72 	te = t + d->ntargets;
73 	for (; t < te && *t; t++) {
74 		ifp = (*t)->ifs;
75 		e = ifp + NAOEIFS;
76 		for (; ifp < e && ifp->nd; ifp++) {
77 			for (nnd = nds; nnd < nd; nnd++)
78 				if (*nnd == ifp->nd)
79 					break;
80 			if (nnd == nd && nd != ne)
81 				*nd++ = ifp->nd;
82 		}
83 	}
84 
85 	ne = nd;
86 	nd = nds;
87 	if (*nd == NULL)
88 		return snprintf(page, PAGE_SIZE, "none\n");
89 	for (p = page; nd < ne; nd++)
90 		p += snprintf(p, PAGE_SIZE - (p-page), "%s%s",
91 			p == page ? "" : ",", (*nd)->name);
92 	p += snprintf(p, PAGE_SIZE - (p-page), "\n");
93 	return p-page;
94 }
95 /* firmware version */
96 static ssize_t aoedisk_show_fwver(struct device *dev,
97 				  struct device_attribute *attr, char *page)
98 {
99 	struct gendisk *disk = dev_to_disk(dev);
100 	struct aoedev *d = disk->private_data;
101 
102 	return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
103 }
104 static ssize_t aoedisk_show_payload(struct device *dev,
105 				    struct device_attribute *attr, char *page)
106 {
107 	struct gendisk *disk = dev_to_disk(dev);
108 	struct aoedev *d = disk->private_data;
109 
110 	return snprintf(page, PAGE_SIZE, "%lu\n", d->maxbcnt);
111 }
112 
113 static int aoedisk_debugfs_show(struct seq_file *s, void *ignored)
114 {
115 	struct aoedev *d;
116 	struct aoetgt **t, **te;
117 	struct aoeif *ifp, *ife;
118 	unsigned long flags;
119 	char c;
120 
121 	d = s->private;
122 	seq_printf(s, "rttavg: %d rttdev: %d\n",
123 		d->rttavg >> RTTSCALE,
124 		d->rttdev >> RTTDSCALE);
125 	seq_printf(s, "nskbpool: %d\n", skb_queue_len(&d->skbpool));
126 	seq_printf(s, "kicked: %ld\n", d->kicked);
127 	seq_printf(s, "maxbcnt: %ld\n", d->maxbcnt);
128 	seq_printf(s, "ref: %ld\n", d->ref);
129 
130 	spin_lock_irqsave(&d->lock, flags);
131 	t = d->targets;
132 	te = t + d->ntargets;
133 	for (; t < te && *t; t++) {
134 		c = '\t';
135 		seq_printf(s, "falloc: %ld\n", (*t)->falloc);
136 		seq_printf(s, "ffree: %p\n",
137 			list_empty(&(*t)->ffree) ? NULL : (*t)->ffree.next);
138 		seq_printf(s, "%pm:%d:%d:%d\n", (*t)->addr, (*t)->nout,
139 			(*t)->maxout, (*t)->nframes);
140 		seq_printf(s, "\tssthresh:%d\n", (*t)->ssthresh);
141 		seq_printf(s, "\ttaint:%d\n", (*t)->taint);
142 		seq_printf(s, "\tr:%d\n", (*t)->rpkts);
143 		seq_printf(s, "\tw:%d\n", (*t)->wpkts);
144 		ifp = (*t)->ifs;
145 		ife = ifp + ARRAY_SIZE((*t)->ifs);
146 		for (; ifp->nd && ifp < ife; ifp++) {
147 			seq_printf(s, "%c%s", c, ifp->nd->name);
148 			c = ',';
149 		}
150 		seq_puts(s, "\n");
151 	}
152 	spin_unlock_irqrestore(&d->lock, flags);
153 
154 	return 0;
155 }
156 
157 static int aoe_debugfs_open(struct inode *inode, struct file *file)
158 {
159 	return single_open(file, aoedisk_debugfs_show, inode->i_private);
160 }
161 
162 static DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL);
163 static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL);
164 static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL);
165 static struct device_attribute dev_attr_firmware_version = {
166 	.attr = { .name = "firmware-version", .mode = S_IRUGO },
167 	.show = aoedisk_show_fwver,
168 };
169 static DEVICE_ATTR(payload, S_IRUGO, aoedisk_show_payload, NULL);
170 
171 static struct attribute *aoe_attrs[] = {
172 	&dev_attr_state.attr,
173 	&dev_attr_mac.attr,
174 	&dev_attr_netif.attr,
175 	&dev_attr_firmware_version.attr,
176 	&dev_attr_payload.attr,
177 	NULL,
178 };
179 
180 static const struct attribute_group attr_group = {
181 	.attrs = aoe_attrs,
182 };
183 
184 static const struct file_operations aoe_debugfs_fops = {
185 	.open = aoe_debugfs_open,
186 	.read = seq_read,
187 	.llseek = seq_lseek,
188 	.release = single_release,
189 };
190 
191 static void
192 aoedisk_add_debugfs(struct aoedev *d)
193 {
194 	struct dentry *entry;
195 	char *p;
196 
197 	if (aoe_debugfs_dir == NULL)
198 		return;
199 	p = strchr(d->gd->disk_name, '/');
200 	if (p == NULL)
201 		p = d->gd->disk_name;
202 	else
203 		p++;
204 	BUG_ON(*p == '\0');
205 	entry = debugfs_create_file(p, 0444, aoe_debugfs_dir, d,
206 				    &aoe_debugfs_fops);
207 	if (IS_ERR_OR_NULL(entry)) {
208 		pr_info("aoe: cannot create debugfs file for %s\n",
209 			d->gd->disk_name);
210 		return;
211 	}
212 	BUG_ON(d->debugfs);
213 	d->debugfs = entry;
214 }
215 void
216 aoedisk_rm_debugfs(struct aoedev *d)
217 {
218 	debugfs_remove(d->debugfs);
219 	d->debugfs = NULL;
220 }
221 
222 static int
223 aoedisk_add_sysfs(struct aoedev *d)
224 {
225 	return sysfs_create_group(&disk_to_dev(d->gd)->kobj, &attr_group);
226 }
227 void
228 aoedisk_rm_sysfs(struct aoedev *d)
229 {
230 	sysfs_remove_group(&disk_to_dev(d->gd)->kobj, &attr_group);
231 }
232 
233 static int
234 aoeblk_open(struct block_device *bdev, fmode_t mode)
235 {
236 	struct aoedev *d = bdev->bd_disk->private_data;
237 	ulong flags;
238 
239 	if (!virt_addr_valid(d)) {
240 		pr_crit("aoe: invalid device pointer in %s\n",
241 			__func__);
242 		WARN_ON(1);
243 		return -ENODEV;
244 	}
245 	if (!(d->flags & DEVFL_UP) || d->flags & DEVFL_TKILL)
246 		return -ENODEV;
247 
248 	mutex_lock(&aoeblk_mutex);
249 	spin_lock_irqsave(&d->lock, flags);
250 	if (d->flags & DEVFL_UP && !(d->flags & DEVFL_TKILL)) {
251 		d->nopen++;
252 		spin_unlock_irqrestore(&d->lock, flags);
253 		mutex_unlock(&aoeblk_mutex);
254 		return 0;
255 	}
256 	spin_unlock_irqrestore(&d->lock, flags);
257 	mutex_unlock(&aoeblk_mutex);
258 	return -ENODEV;
259 }
260 
261 static void
262 aoeblk_release(struct gendisk *disk, fmode_t mode)
263 {
264 	struct aoedev *d = disk->private_data;
265 	ulong flags;
266 
267 	spin_lock_irqsave(&d->lock, flags);
268 
269 	if (--d->nopen == 0) {
270 		spin_unlock_irqrestore(&d->lock, flags);
271 		aoecmd_cfg(d->aoemajor, d->aoeminor);
272 		return;
273 	}
274 	spin_unlock_irqrestore(&d->lock, flags);
275 }
276 
277 static void
278 aoeblk_request(struct request_queue *q)
279 {
280 	struct aoedev *d;
281 	struct request *rq;
282 
283 	d = q->queuedata;
284 	if ((d->flags & DEVFL_UP) == 0) {
285 		pr_info_ratelimited("aoe: device %ld.%d is not up\n",
286 			d->aoemajor, d->aoeminor);
287 		while ((rq = blk_peek_request(q))) {
288 			blk_start_request(rq);
289 			aoe_end_request(d, rq, 1);
290 		}
291 		return;
292 	}
293 	aoecmd_work(d);
294 }
295 
296 static int
297 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
298 {
299 	struct aoedev *d = bdev->bd_disk->private_data;
300 
301 	if ((d->flags & DEVFL_UP) == 0) {
302 		printk(KERN_ERR "aoe: disk not up\n");
303 		return -ENODEV;
304 	}
305 
306 	geo->cylinders = d->geo.cylinders;
307 	geo->heads = d->geo.heads;
308 	geo->sectors = d->geo.sectors;
309 	return 0;
310 }
311 
312 static int
313 aoeblk_ioctl(struct block_device *bdev, fmode_t mode, uint cmd, ulong arg)
314 {
315 	struct aoedev *d;
316 
317 	if (!arg)
318 		return -EINVAL;
319 
320 	d = bdev->bd_disk->private_data;
321 	if ((d->flags & DEVFL_UP) == 0) {
322 		pr_err("aoe: disk not up\n");
323 		return -ENODEV;
324 	}
325 
326 	if (cmd == HDIO_GET_IDENTITY) {
327 		if (!copy_to_user((void __user *) arg, &d->ident,
328 			sizeof(d->ident)))
329 			return 0;
330 		return -EFAULT;
331 	}
332 
333 	/* udev calls scsi_id, which uses SG_IO, resulting in noise */
334 	if (cmd != SG_IO)
335 		pr_info("aoe: unknown ioctl 0x%x\n", cmd);
336 
337 	return -ENOTTY;
338 }
339 
340 static const struct block_device_operations aoe_bdops = {
341 	.open = aoeblk_open,
342 	.release = aoeblk_release,
343 	.ioctl = aoeblk_ioctl,
344 	.getgeo = aoeblk_getgeo,
345 	.owner = THIS_MODULE,
346 };
347 
348 /* alloc_disk and add_disk can sleep */
349 void
350 aoeblk_gdalloc(void *vp)
351 {
352 	struct aoedev *d = vp;
353 	struct gendisk *gd;
354 	mempool_t *mp;
355 	struct request_queue *q;
356 	enum { KB = 1024, MB = KB * KB, READ_AHEAD = 2 * MB, };
357 	ulong flags;
358 	int late = 0;
359 
360 	spin_lock_irqsave(&d->lock, flags);
361 	if (d->flags & DEVFL_GDALLOC
362 	&& !(d->flags & DEVFL_TKILL)
363 	&& !(d->flags & DEVFL_GD_NOW))
364 		d->flags |= DEVFL_GD_NOW;
365 	else
366 		late = 1;
367 	spin_unlock_irqrestore(&d->lock, flags);
368 	if (late)
369 		return;
370 
371 	gd = alloc_disk(AOE_PARTITIONS);
372 	if (gd == NULL) {
373 		pr_err("aoe: cannot allocate disk structure for %ld.%d\n",
374 			d->aoemajor, d->aoeminor);
375 		goto err;
376 	}
377 
378 	mp = mempool_create(MIN_BUFS, mempool_alloc_slab, mempool_free_slab,
379 		buf_pool_cache);
380 	if (mp == NULL) {
381 		printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
382 			d->aoemajor, d->aoeminor);
383 		goto err_disk;
384 	}
385 	q = blk_init_queue(aoeblk_request, &d->lock);
386 	if (q == NULL) {
387 		pr_err("aoe: cannot allocate block queue for %ld.%d\n",
388 			d->aoemajor, d->aoeminor);
389 		goto err_mempool;
390 	}
391 
392 	spin_lock_irqsave(&d->lock, flags);
393 	WARN_ON(!(d->flags & DEVFL_GD_NOW));
394 	WARN_ON(!(d->flags & DEVFL_GDALLOC));
395 	WARN_ON(d->flags & DEVFL_TKILL);
396 	WARN_ON(d->gd);
397 	WARN_ON(d->flags & DEVFL_UP);
398 	blk_queue_max_hw_sectors(q, BLK_DEF_MAX_SECTORS);
399 	q->backing_dev_info.name = "aoe";
400 	q->backing_dev_info.ra_pages = READ_AHEAD / PAGE_SIZE;
401 	d->bufpool = mp;
402 	d->blkq = gd->queue = q;
403 	q->queuedata = d;
404 	d->gd = gd;
405 	if (aoe_maxsectors)
406 		blk_queue_max_hw_sectors(q, aoe_maxsectors);
407 	gd->major = AOE_MAJOR;
408 	gd->first_minor = d->sysminor;
409 	gd->fops = &aoe_bdops;
410 	gd->private_data = d;
411 	set_capacity(gd, d->ssize);
412 	snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
413 		d->aoemajor, d->aoeminor);
414 
415 	d->flags &= ~DEVFL_GDALLOC;
416 	d->flags |= DEVFL_UP;
417 
418 	spin_unlock_irqrestore(&d->lock, flags);
419 
420 	add_disk(gd);
421 	aoedisk_add_sysfs(d);
422 	aoedisk_add_debugfs(d);
423 
424 	spin_lock_irqsave(&d->lock, flags);
425 	WARN_ON(!(d->flags & DEVFL_GD_NOW));
426 	d->flags &= ~DEVFL_GD_NOW;
427 	spin_unlock_irqrestore(&d->lock, flags);
428 	return;
429 
430 err_mempool:
431 	mempool_destroy(mp);
432 err_disk:
433 	put_disk(gd);
434 err:
435 	spin_lock_irqsave(&d->lock, flags);
436 	d->flags &= ~DEVFL_GD_NOW;
437 	schedule_work(&d->work);
438 	spin_unlock_irqrestore(&d->lock, flags);
439 }
440 
441 void
442 aoeblk_exit(void)
443 {
444 	debugfs_remove_recursive(aoe_debugfs_dir);
445 	aoe_debugfs_dir = NULL;
446 	kmem_cache_destroy(buf_pool_cache);
447 }
448 
449 int __init
450 aoeblk_init(void)
451 {
452 	buf_pool_cache = kmem_cache_create("aoe_bufs",
453 					   sizeof(struct buf),
454 					   0, 0, NULL);
455 	if (buf_pool_cache == NULL)
456 		return -ENOMEM;
457 	aoe_debugfs_dir = debugfs_create_dir("aoe", NULL);
458 	if (IS_ERR_OR_NULL(aoe_debugfs_dir)) {
459 		pr_info("aoe: cannot create debugfs directory\n");
460 		aoe_debugfs_dir = NULL;
461 	}
462 	return 0;
463 }
464 
465