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/blk-mq.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/netdevice.h>
16#include <linux/mutex.h>
17#include <linux/export.h>
18#include <linux/moduleparam.h>
19#include <linux/debugfs.h>
20#include <scsi/sg.h>
21#include "aoe.h"
22
23static DEFINE_MUTEX(aoeblk_mutex);
24static struct kmem_cache *buf_pool_cache;
25static struct dentry *aoe_debugfs_dir;
26
27/* random default picked from the historic block max_sectors cap */
28static int aoe_maxsectors = 2560;
29module_param(aoe_maxsectors, int, 0644);
30MODULE_PARM_DESC(aoe_maxsectors,
31 "When nonzero, set the maximum number of sectors per I/O request");
32
33static ssize_t aoedisk_show_state(struct device *dev,
34 struct device_attribute *attr, char *page)
35{
36 struct gendisk *disk = dev_to_disk(dev);
37 struct aoedev *d = disk->private_data;
38
39 return sysfs_emit(buf: page, fmt: "%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}
45static 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 sysfs_emit(buf: page, fmt: "none\n");
54 return sysfs_emit(buf: page, fmt: "%pm\n", t->addr);
55}
56static 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 sysfs_emit(buf: page, fmt: "none\n");
87 for (p = page; nd < ne; nd++)
88 p += scnprintf(buf: p, PAGE_SIZE - (p-page), fmt: "%s%s",
89 p == page ? "" : ",", (*nd)->name);
90 p += scnprintf(buf: p, PAGE_SIZE - (p-page), fmt: "\n");
91 return p-page;
92}
93/* firmware version */
94static 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 sysfs_emit(buf: page, fmt: "0x%04x\n", (unsigned int) d->fw_ver);
101}
102static 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 sysfs_emit(buf: page, fmt: "%lu\n", d->maxbcnt);
109}
110
111static int aoe_debugfs_show(struct seq_file *s, void *ignored)
112{
113 struct aoedev *d;
114 struct aoetgt **t, **te;
115 struct aoeif *ifp, *ife;
116 unsigned long flags;
117 char c;
118
119 d = s->private;
120 seq_printf(m: s, fmt: "rttavg: %d rttdev: %d\n",
121 d->rttavg >> RTTSCALE,
122 d->rttdev >> RTTDSCALE);
123 seq_printf(m: s, fmt: "nskbpool: %d\n", skb_queue_len(list_: &d->skbpool));
124 seq_printf(m: s, fmt: "kicked: %ld\n", d->kicked);
125 seq_printf(m: s, fmt: "maxbcnt: %ld\n", d->maxbcnt);
126 seq_printf(m: s, fmt: "ref: %ld\n", d->ref);
127
128 spin_lock_irqsave(&d->lock, flags);
129 t = d->targets;
130 te = t + d->ntargets;
131 for (; t < te && *t; t++) {
132 c = '\t';
133 seq_printf(m: s, fmt: "falloc: %ld\n", (*t)->falloc);
134 seq_printf(m: s, fmt: "ffree: %p\n",
135 list_empty(head: &(*t)->ffree) ? NULL : (*t)->ffree.next);
136 seq_printf(m: s, fmt: "%pm:%d:%d:%d\n", (*t)->addr, (*t)->nout,
137 (*t)->maxout, (*t)->nframes);
138 seq_printf(m: s, fmt: "\tssthresh:%d\n", (*t)->ssthresh);
139 seq_printf(m: s, fmt: "\ttaint:%d\n", (*t)->taint);
140 seq_printf(m: s, fmt: "\tr:%d\n", (*t)->rpkts);
141 seq_printf(m: s, fmt: "\tw:%d\n", (*t)->wpkts);
142 ifp = (*t)->ifs;
143 ife = ifp + ARRAY_SIZE((*t)->ifs);
144 for (; ifp->nd && ifp < ife; ifp++) {
145 seq_printf(m: s, fmt: "%c%s", c, ifp->nd->name);
146 c = ',';
147 }
148 seq_puts(m: s, s: "\n");
149 }
150 spin_unlock_irqrestore(lock: &d->lock, flags);
151
152 return 0;
153}
154DEFINE_SHOW_ATTRIBUTE(aoe_debugfs);
155
156static DEVICE_ATTR(state, 0444, aoedisk_show_state, NULL);
157static DEVICE_ATTR(mac, 0444, aoedisk_show_mac, NULL);
158static DEVICE_ATTR(netif, 0444, aoedisk_show_netif, NULL);
159static struct device_attribute dev_attr_firmware_version = {
160 .attr = { .name = "firmware-version", .mode = 0444 },
161 .show = aoedisk_show_fwver,
162};
163static DEVICE_ATTR(payload, 0444, aoedisk_show_payload, NULL);
164
165static struct attribute *aoe_attrs[] = {
166 &dev_attr_state.attr,
167 &dev_attr_mac.attr,
168 &dev_attr_netif.attr,
169 &dev_attr_firmware_version.attr,
170 &dev_attr_payload.attr,
171 NULL,
172};
173
174static const struct attribute_group aoe_attr_group = {
175 .attrs = aoe_attrs,
176};
177
178static const struct attribute_group *aoe_attr_groups[] = {
179 &aoe_attr_group,
180 NULL,
181};
182
183static void
184aoedisk_add_debugfs(struct aoedev *d)
185{
186 char *p;
187
188 if (aoe_debugfs_dir == NULL)
189 return;
190 p = strchr(d->gd->disk_name, '/');
191 if (p == NULL)
192 p = d->gd->disk_name;
193 else
194 p++;
195 BUG_ON(*p == '\0');
196 d->debugfs = debugfs_create_file(name: p, mode: 0444, parent: aoe_debugfs_dir, data: d,
197 fops: &aoe_debugfs_fops);
198}
199void
200aoedisk_rm_debugfs(struct aoedev *d)
201{
202 debugfs_remove(dentry: d->debugfs);
203 d->debugfs = NULL;
204}
205
206static int
207aoeblk_open(struct gendisk *disk, blk_mode_t mode)
208{
209 struct aoedev *d = disk->private_data;
210 ulong flags;
211
212 if (!virt_addr_valid(d)) {
213 pr_crit("aoe: invalid device pointer in %s\n",
214 __func__);
215 WARN_ON(1);
216 return -ENODEV;
217 }
218 if (!(d->flags & DEVFL_UP) || d->flags & DEVFL_TKILL)
219 return -ENODEV;
220
221 mutex_lock(&aoeblk_mutex);
222 spin_lock_irqsave(&d->lock, flags);
223 if (d->flags & DEVFL_UP && !(d->flags & DEVFL_TKILL)) {
224 d->nopen++;
225 spin_unlock_irqrestore(lock: &d->lock, flags);
226 mutex_unlock(lock: &aoeblk_mutex);
227 return 0;
228 }
229 spin_unlock_irqrestore(lock: &d->lock, flags);
230 mutex_unlock(lock: &aoeblk_mutex);
231 return -ENODEV;
232}
233
234static void
235aoeblk_release(struct gendisk *disk)
236{
237 struct aoedev *d = disk->private_data;
238 ulong flags;
239
240 spin_lock_irqsave(&d->lock, flags);
241
242 if (--d->nopen == 0) {
243 spin_unlock_irqrestore(lock: &d->lock, flags);
244 aoecmd_cfg(aoemajor: d->aoemajor, aoeminor: d->aoeminor);
245 return;
246 }
247 spin_unlock_irqrestore(lock: &d->lock, flags);
248}
249
250static blk_status_t aoeblk_queue_rq(struct blk_mq_hw_ctx *hctx,
251 const struct blk_mq_queue_data *bd)
252{
253 struct aoedev *d = hctx->queue->queuedata;
254
255 spin_lock_irq(lock: &d->lock);
256
257 if ((d->flags & DEVFL_UP) == 0) {
258 pr_info_ratelimited("aoe: device %ld.%d is not up\n",
259 d->aoemajor, d->aoeminor);
260 spin_unlock_irq(lock: &d->lock);
261 blk_mq_start_request(rq: bd->rq);
262 return BLK_STS_IOERR;
263 }
264
265 list_add_tail(new: &bd->rq->queuelist, head: &d->rq_list);
266 aoecmd_work(d);
267 spin_unlock_irq(lock: &d->lock);
268 return BLK_STS_OK;
269}
270
271static int
272aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
273{
274 struct aoedev *d = bdev->bd_disk->private_data;
275
276 if ((d->flags & DEVFL_UP) == 0) {
277 printk(KERN_ERR "aoe: disk not up\n");
278 return -ENODEV;
279 }
280
281 geo->cylinders = d->geo.cylinders;
282 geo->heads = d->geo.heads;
283 geo->sectors = d->geo.sectors;
284 return 0;
285}
286
287static int
288aoeblk_ioctl(struct block_device *bdev, blk_mode_t mode, uint cmd, ulong arg)
289{
290 struct aoedev *d;
291
292 if (!arg)
293 return -EINVAL;
294
295 d = bdev->bd_disk->private_data;
296 if ((d->flags & DEVFL_UP) == 0) {
297 pr_err("aoe: disk not up\n");
298 return -ENODEV;
299 }
300
301 if (cmd == HDIO_GET_IDENTITY) {
302 if (!copy_to_user(to: (void __user *) arg, from: &d->ident,
303 n: sizeof(d->ident)))
304 return 0;
305 return -EFAULT;
306 }
307
308 /* udev calls scsi_id, which uses SG_IO, resulting in noise */
309 if (cmd != SG_IO)
310 pr_info("aoe: unknown ioctl 0x%x\n", cmd);
311
312 return -ENOTTY;
313}
314
315static const struct block_device_operations aoe_bdops = {
316 .open = aoeblk_open,
317 .release = aoeblk_release,
318 .ioctl = aoeblk_ioctl,
319 .compat_ioctl = blkdev_compat_ptr_ioctl,
320 .getgeo = aoeblk_getgeo,
321 .owner = THIS_MODULE,
322};
323
324static const struct blk_mq_ops aoeblk_mq_ops = {
325 .queue_rq = aoeblk_queue_rq,
326};
327
328/* blk_mq_alloc_disk and add_disk can sleep */
329void
330aoeblk_gdalloc(void *vp)
331{
332 struct aoedev *d = vp;
333 struct gendisk *gd;
334 mempool_t *mp;
335 struct blk_mq_tag_set *set;
336 sector_t ssize;
337 struct queue_limits lim = {
338 .max_hw_sectors = aoe_maxsectors,
339 .io_opt = SZ_2M,
340 };
341 ulong flags;
342 int late = 0;
343 int err;
344
345 spin_lock_irqsave(&d->lock, flags);
346 if (d->flags & DEVFL_GDALLOC
347 && !(d->flags & DEVFL_TKILL)
348 && !(d->flags & DEVFL_GD_NOW))
349 d->flags |= DEVFL_GD_NOW;
350 else
351 late = 1;
352 spin_unlock_irqrestore(lock: &d->lock, flags);
353 if (late)
354 return;
355
356 mp = mempool_create(min_nr: MIN_BUFS, alloc_fn: mempool_alloc_slab, free_fn: mempool_free_slab,
357 pool_data: buf_pool_cache);
358 if (mp == NULL) {
359 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
360 d->aoemajor, d->aoeminor);
361 goto err;
362 }
363
364 set = &d->tag_set;
365 set->ops = &aoeblk_mq_ops;
366 set->cmd_size = sizeof(struct aoe_req);
367 set->nr_hw_queues = 1;
368 set->queue_depth = 128;
369 set->numa_node = NUMA_NO_NODE;
370 set->flags = BLK_MQ_F_SHOULD_MERGE;
371 err = blk_mq_alloc_tag_set(set);
372 if (err) {
373 pr_err("aoe: cannot allocate tag set for %ld.%d\n",
374 d->aoemajor, d->aoeminor);
375 goto err_mempool;
376 }
377
378 gd = blk_mq_alloc_disk(set, &lim, d);
379 if (IS_ERR(ptr: gd)) {
380 pr_err("aoe: cannot allocate block queue for %ld.%d\n",
381 d->aoemajor, d->aoeminor);
382 goto err_tagset;
383 }
384
385 spin_lock_irqsave(&d->lock, flags);
386 WARN_ON(!(d->flags & DEVFL_GD_NOW));
387 WARN_ON(!(d->flags & DEVFL_GDALLOC));
388 WARN_ON(d->flags & DEVFL_TKILL);
389 WARN_ON(d->gd);
390 WARN_ON(d->flags & DEVFL_UP);
391 d->bufpool = mp;
392 d->blkq = gd->queue;
393 d->gd = gd;
394 gd->major = AOE_MAJOR;
395 gd->first_minor = d->sysminor;
396 gd->minors = AOE_PARTITIONS;
397 gd->fops = &aoe_bdops;
398 gd->private_data = d;
399 ssize = d->ssize;
400 snprintf(buf: gd->disk_name, size: sizeof gd->disk_name, fmt: "etherd/e%ld.%d",
401 d->aoemajor, d->aoeminor);
402
403 d->flags &= ~DEVFL_GDALLOC;
404 d->flags |= DEVFL_UP;
405
406 spin_unlock_irqrestore(lock: &d->lock, flags);
407
408 set_capacity(disk: gd, size: ssize);
409
410 err = device_add_disk(NULL, disk: gd, groups: aoe_attr_groups);
411 if (err)
412 goto out_disk_cleanup;
413 aoedisk_add_debugfs(d);
414
415 spin_lock_irqsave(&d->lock, flags);
416 WARN_ON(!(d->flags & DEVFL_GD_NOW));
417 d->flags &= ~DEVFL_GD_NOW;
418 spin_unlock_irqrestore(lock: &d->lock, flags);
419 return;
420
421out_disk_cleanup:
422 put_disk(disk: gd);
423err_tagset:
424 blk_mq_free_tag_set(set);
425err_mempool:
426 mempool_destroy(pool: mp);
427err:
428 spin_lock_irqsave(&d->lock, flags);
429 d->flags &= ~DEVFL_GD_NOW;
430 queue_work(wq: aoe_wq, work: &d->work);
431 spin_unlock_irqrestore(lock: &d->lock, flags);
432}
433
434void
435aoeblk_exit(void)
436{
437 debugfs_remove_recursive(dentry: aoe_debugfs_dir);
438 aoe_debugfs_dir = NULL;
439 kmem_cache_destroy(s: buf_pool_cache);
440}
441
442int __init
443aoeblk_init(void)
444{
445 buf_pool_cache = kmem_cache_create(name: "aoe_bufs",
446 size: sizeof(struct buf),
447 align: 0, flags: 0, NULL);
448 if (buf_pool_cache == NULL)
449 return -ENOMEM;
450 aoe_debugfs_dir = debugfs_create_dir(name: "aoe", NULL);
451 return 0;
452}
453
454

source code of linux/drivers/block/aoe/aoeblk.c