drivers/block/aoe/aoeblk.c

   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/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, 0444, aoedisk_show_state, NULL);
 163 static DEVICE_ATTR(mac, 0444, aoedisk_show_mac, NULL);
 164 static DEVICE_ATTR(netif, 0444, aoedisk_show_netif, NULL);
 165 static struct device_attribute dev_attr_firmware_version = {
 166         .attr = { .name = "firmware-version", .mode = 0444 },
 167         .show = aoedisk_show_fwver,
 168 };
 169 static DEVICE_ATTR(payload, 0444, 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 aoe_attr_group = {
 181         .attrs = aoe_attrs,
 182 };
 183
 184 static const struct attribute_group *aoe_attr_groups[] = {
 185         &aoe_attr_group,
 186         NULL,
 187 };
 188
 189 static const struct file_operations aoe_debugfs_fops = {
 190         .open = aoe_debugfs_open,
 191         .read = seq_read,
 192         .llseek = seq_lseek,
 193         .release = single_release,
 194 };
 195
 196 static void
 197 aoedisk_add_debugfs(struct aoedev *d)
 198 {
 199         struct dentry *entry;
 200         char *p;
 201
 202         if (aoe_debugfs_dir == NULL)
 203                 return;
 204         p = strchr(d->gd->disk_name, '/');
 205         if (p == NULL)
 206                 p = d->gd->disk_name;
 207         else
 208                 p++;
 209         BUG_ON(*p == '\0');
 210         entry = debugfs_create_file(p, 0444, aoe_debugfs_dir, d,
 211                                     &aoe_debugfs_fops);
 212         if (IS_ERR_OR_NULL(entry)) {
 213                 pr_info("aoe: cannot create debugfs file for %s\n",
 214                         d->gd->disk_name);
 215                 return;
 216         }
 217         BUG_ON(d->debugfs);
 218         d->debugfs = entry;
 219 }
 220 void
 221 aoedisk_rm_debugfs(struct aoedev *d)
 222 {
 223         debugfs_remove(d->debugfs);
 224         d->debugfs = NULL;
 225 }
 226
 227 static int
 228 aoeblk_open(struct block_device *bdev, fmode_t mode)
 229 {
 230         struct aoedev *d = bdev->bd_disk->private_data;
 231         ulong flags;
 232
 233         if (!virt_addr_valid(d)) {
 234                 pr_crit("aoe: invalid device pointer in %s\n",
 235                         __func__);
 236                 WARN_ON(1);
 237                 return -ENODEV;
 238         }
 239         if (!(d->flags & DEVFL_UP) || d->flags & DEVFL_TKILL)
 240                 return -ENODEV;
 241
 242         mutex_lock(&aoeblk_mutex);
 243         spin_lock_irqsave(&d->lock, flags);
 244         if (d->flags & DEVFL_UP && !(d->flags & DEVFL_TKILL)) {
 245                 d->nopen++;
 246                 spin_unlock_irqrestore(&d->lock, flags);
 247                 mutex_unlock(&aoeblk_mutex);
 248                 return 0;
 249         }
 250         spin_unlock_irqrestore(&d->lock, flags);
 251         mutex_unlock(&aoeblk_mutex);
 252         return -ENODEV;
 253 }
 254
 255 static void
 256 aoeblk_release(struct gendisk *disk, fmode_t mode)
 257 {
 258         struct aoedev *d = disk->private_data;
 259         ulong flags;
 260
 261         spin_lock_irqsave(&d->lock, flags);
 262
 263         if (--d->nopen == 0) {
 264                 spin_unlock_irqrestore(&d->lock, flags);
 265                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 266                 return;
 267         }
 268         spin_unlock_irqrestore(&d->lock, flags);
 269 }
 270
 271 static blk_status_t aoeblk_queue_rq(struct blk_mq_hw_ctx *hctx,
 272                                     const struct blk_mq_queue_data *bd)
 273 {
 274         struct aoedev *d = hctx->queue->queuedata;
 275
 276         spin_lock_irq(&d->lock);
 277
 278         if ((d->flags & DEVFL_UP) == 0) {
 279                 pr_info_ratelimited("aoe: device %ld.%d is not up\n",
 280                         d->aoemajor, d->aoeminor);
 281                 spin_unlock_irq(&d->lock);
 282                 blk_mq_start_request(bd->rq);
 283                 return BLK_STS_IOERR;
 284         }
 285
 286         list_add_tail(&bd->rq->queuelist, &d->rq_list);
 287         aoecmd_work(d);
 288         spin_unlock_irq(&d->lock);
 289         return BLK_STS_OK;
 290 }
 291
 292 static int
 293 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 294 {
 295         struct aoedev *d = bdev->bd_disk->private_data;
 296
 297         if ((d->flags & DEVFL_UP) == 0) {
 298                 printk(KERN_ERR "aoe: disk not up\n");
 299                 return -ENODEV;
 300         }
 301
 302         geo->cylinders = d->geo.cylinders;
 303         geo->heads = d->geo.heads;
 304         geo->sectors = d->geo.sectors;
 305         return 0;
 306 }
 307
 308 static int
 309 aoeblk_ioctl(struct block_device *bdev, fmode_t mode, uint cmd, ulong arg)
 310 {
 311         struct aoedev *d;
 312
 313         if (!arg)
 314                 return -EINVAL;
 315
 316         d = bdev->bd_disk->private_data;
 317         if ((d->flags & DEVFL_UP) == 0) {
 318                 pr_err("aoe: disk not up\n");
 319                 return -ENODEV;
 320         }
 321
 322         if (cmd == HDIO_GET_IDENTITY) {
 323                 if (!copy_to_user((void __user *) arg, &d->ident,
 324                         sizeof(d->ident)))
 325                         return 0;
 326                 return -EFAULT;
 327         }
 328
 329         /* udev calls scsi_id, which uses SG_IO, resulting in noise */
 330         if (cmd != SG_IO)
 331                 pr_info("aoe: unknown ioctl 0x%x\n", cmd);
 332
 333         return -ENOTTY;
 334 }
 335
 336 static const struct block_device_operations aoe_bdops = {
 337         .open = aoeblk_open,
 338         .release = aoeblk_release,
 339         .ioctl = aoeblk_ioctl,
 340         .getgeo = aoeblk_getgeo,
 341         .owner = THIS_MODULE,
 342 };
 343
 344 static const struct blk_mq_ops aoeblk_mq_ops = {
 345         .queue_rq       = aoeblk_queue_rq,
 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         struct blk_mq_tag_set *set;
 357         enum { KB = 1024, MB = KB * KB, READ_AHEAD = 2 * MB, };
 358         ulong flags;
 359         int late = 0;
 360         int err;
 361
 362         spin_lock_irqsave(&d->lock, flags);
 363         if (d->flags & DEVFL_GDALLOC
 364         && !(d->flags & DEVFL_TKILL)
 365         && !(d->flags & DEVFL_GD_NOW))
 366                 d->flags |= DEVFL_GD_NOW;
 367         else
 368                 late = 1;
 369         spin_unlock_irqrestore(&d->lock, flags);
 370         if (late)
 371                 return;
 372
 373         gd = alloc_disk(AOE_PARTITIONS);
 374         if (gd == NULL) {
 375                 pr_err("aoe: cannot allocate disk structure for %ld.%d\n",
 376                         d->aoemajor, d->aoeminor);
 377                 goto err;
 378         }
 379
 380         mp = mempool_create(MIN_BUFS, mempool_alloc_slab, mempool_free_slab,
 381                 buf_pool_cache);
 382         if (mp == NULL) {
 383                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
 384                         d->aoemajor, d->aoeminor);
 385                 goto err_disk;
 386         }
 387
 388         set = &d->tag_set;
 389         set->ops = &aoeblk_mq_ops;
 390         set->cmd_size = sizeof(struct aoe_req);
 391         set->nr_hw_queues = 1;
 392         set->queue_depth = 128;
 393         set->numa_node = NUMA_NO_NODE;
 394         set->flags = BLK_MQ_F_SHOULD_MERGE;
 395         err = blk_mq_alloc_tag_set(set);
 396         if (err) {
 397                 pr_err("aoe: cannot allocate tag set for %ld.%d\n",
 398                         d->aoemajor, d->aoeminor);
 399                 goto err_mempool;
 400         }
 401
 402         q = blk_mq_init_queue(set);
 403         if (IS_ERR(q)) {
 404                 pr_err("aoe: cannot allocate block queue for %ld.%d\n",
 405                         d->aoemajor, d->aoeminor);
 406                 blk_mq_free_tag_set(set);
 407                 goto err_mempool;
 408         }
 409
 410         spin_lock_irqsave(&d->lock, flags);
 411         WARN_ON(!(d->flags & DEVFL_GD_NOW));
 412         WARN_ON(!(d->flags & DEVFL_GDALLOC));
 413         WARN_ON(d->flags & DEVFL_TKILL);
 414         WARN_ON(d->gd);
 415         WARN_ON(d->flags & DEVFL_UP);
 416         blk_queue_max_hw_sectors(q, BLK_DEF_MAX_SECTORS);
 417         q->backing_dev_info->name = "aoe";
 418         q->backing_dev_info->ra_pages = READ_AHEAD / PAGE_SIZE;
 419         d->bufpool = mp;
 420         d->blkq = gd->queue = q;
 421         q->queuedata = d;
 422         d->gd = gd;
 423         if (aoe_maxsectors)
 424                 blk_queue_max_hw_sectors(q, aoe_maxsectors);
 425         gd->major = AOE_MAJOR;
 426         gd->first_minor = d->sysminor;
 427         gd->fops = &aoe_bdops;
 428         gd->private_data = d;
 429         set_capacity(gd, d->ssize);
 430         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
 431                 d->aoemajor, d->aoeminor);
 432
 433         d->flags &= ~DEVFL_GDALLOC;
 434         d->flags |= DEVFL_UP;
 435
 436         spin_unlock_irqrestore(&d->lock, flags);
 437
 438         device_add_disk(NULL, gd, aoe_attr_groups);
 439         aoedisk_add_debugfs(d);
 440
 441         spin_lock_irqsave(&d->lock, flags);
 442         WARN_ON(!(d->flags & DEVFL_GD_NOW));
 443         d->flags &= ~DEVFL_GD_NOW;
 444         spin_unlock_irqrestore(&d->lock, flags);
 445         return;
 446
 447 err_mempool:
 448         mempool_destroy(mp);
 449 err_disk:
 450         put_disk(gd);
 451 err:
 452         spin_lock_irqsave(&d->lock, flags);
 453         d->flags &= ~DEVFL_GD_NOW;
 454         schedule_work(&d->work);
 455         spin_unlock_irqrestore(&d->lock, flags);
 456 }
 457
 458 void
 459 aoeblk_exit(void)
 460 {
 461         debugfs_remove_recursive(aoe_debugfs_dir);
 462         aoe_debugfs_dir = NULL;
 463         kmem_cache_destroy(buf_pool_cache);
 464 }
 465
 466 int __init
 467 aoeblk_init(void)
 468 {
 469         buf_pool_cache = kmem_cache_create("aoe_bufs",
 470                                            sizeof(struct buf),
 471                                            0, 0, NULL);
 472         if (buf_pool_cache == NULL)
 473                 return -ENOMEM;
 474         aoe_debugfs_dir = debugfs_create_dir("aoe", NULL);
 475         if (IS_ERR_OR_NULL(aoe_debugfs_dir)) {
 476                 pr_info("aoe: cannot create debugfs directory\n");
 477                 aoe_debugfs_dir = NULL;
 478         }
 479         return 0;
 480 }
 481