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/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
  23 static DEFINE_MUTEX(aoeblk_mutex);
  24 static struct kmem_cache *buf_pool_cache;
  25 static struct dentry *aoe_debugfs_dir;
  26
  27 /* random default picked from the historic block max_sectors cap */
  28 static int aoe_maxsectors = 2560;
  29 module_param(aoe_maxsectors, int, 0644);
  30 MODULE_PARM_DESC(aoe_maxsectors,
  31         "When nonzero, set the maximum number of sectors per I/O request");
  32
  33 static 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(page, "%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 sysfs_emit(page, "none\n");
  54         return sysfs_emit(page, "%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 sysfs_emit(page, "none\n");
  87         for (p = page; nd < ne; nd++)
  88                 p += scnprintf(p, PAGE_SIZE - (p-page), "%s%s",
  89                         p == page ? "" : ",", (*nd)->name);
  90         p += scnprintf(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 sysfs_emit(page, "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 sysfs_emit(page, "%lu\n", d->maxbcnt);
 109 }
 110
 111 static 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(s, "rttavg: %d rttdev: %d\n",
 121                 d->rttavg >> RTTSCALE,
 122                 d->rttdev >> RTTDSCALE);
 123         seq_printf(s, "nskbpool: %d\n", skb_queue_len(&d->skbpool));
 124         seq_printf(s, "kicked: %ld\n", d->kicked);
 125         seq_printf(s, "maxbcnt: %ld\n", d->maxbcnt);
 126         seq_printf(s, "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(s, "falloc: %ld\n", (*t)->falloc);
 134                 seq_printf(s, "ffree: %p\n",
 135                         list_empty(&(*t)->ffree) ? NULL : (*t)->ffree.next);
 136                 seq_printf(s, "%pm:%d:%d:%d\n", (*t)->addr, (*t)->nout,
 137                         (*t)->maxout, (*t)->nframes);
 138                 seq_printf(s, "\tssthresh:%d\n", (*t)->ssthresh);
 139                 seq_printf(s, "\ttaint:%d\n", (*t)->taint);
 140                 seq_printf(s, "\tr:%d\n", (*t)->rpkts);
 141                 seq_printf(s, "\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(s, "%c%s", c, ifp->nd->name);
 146                         c = ',';
 147                 }
 148                 seq_puts(s, "\n");
 149         }
 150         spin_unlock_irqrestore(&d->lock, flags);
 151
 152         return 0;
 153 }
 154 DEFINE_SHOW_ATTRIBUTE(aoe_debugfs);
 155
 156 static DEVICE_ATTR(state, 0444, aoedisk_show_state, NULL);
 157 static DEVICE_ATTR(mac, 0444, aoedisk_show_mac, NULL);
 158 static DEVICE_ATTR(netif, 0444, aoedisk_show_netif, NULL);
 159 static struct device_attribute dev_attr_firmware_version = {
 160         .attr = { .name = "firmware-version", .mode = 0444 },
 161         .show = aoedisk_show_fwver,
 162 };
 163 static DEVICE_ATTR(payload, 0444, aoedisk_show_payload, NULL);
 164
 165 static 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
 174 static const struct attribute_group aoe_attr_group = {
 175         .attrs = aoe_attrs,
 176 };
 177
 178 static const struct attribute_group *aoe_attr_groups[] = {
 179         &aoe_attr_group,
 180         NULL,
 181 };
 182
 183 static void
 184 aoedisk_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(p, 0444, aoe_debugfs_dir, d,
 197                                          &aoe_debugfs_fops);
 198 }
 199 void
 200 aoedisk_rm_debugfs(struct aoedev *d)
 201 {
 202         debugfs_remove(d->debugfs);
 203         d->debugfs = NULL;
 204 }
 205
 206 static int
 207 aoeblk_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(&d->lock, flags);
 226                 mutex_unlock(&aoeblk_mutex);
 227                 return 0;
 228         }
 229         spin_unlock_irqrestore(&d->lock, flags);
 230         mutex_unlock(&aoeblk_mutex);
 231         return -ENODEV;
 232 }
 233
 234 static void
 235 aoeblk_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(&d->lock, flags);
 244                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 245                 return;
 246         }
 247         spin_unlock_irqrestore(&d->lock, flags);
 248 }
 249
 250 static 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(&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(&d->lock);
 261                 blk_mq_start_request(bd->rq);
 262                 return BLK_STS_IOERR;
 263         }
 264
 265         list_add_tail(&bd->rq->queuelist, &d->rq_list);
 266         aoecmd_work(d);
 267         spin_unlock_irq(&d->lock);
 268         return BLK_STS_OK;
 269 }
 270
 271 static int
 272 aoeblk_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
 287 static int
 288 aoeblk_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((void __user *) arg, &d->ident,
 303                         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
 315 static 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
 324 static 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 */
 329 void
 330 aoeblk_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                 .features               = BLK_FEAT_ROTATIONAL,
 341         };
 342         ulong flags;
 343         int late = 0;
 344         int err;
 345
 346         spin_lock_irqsave(&d->lock, flags);
 347         if (d->flags & DEVFL_GDALLOC
 348         && !(d->flags & DEVFL_TKILL)
 349         && !(d->flags & DEVFL_GD_NOW))
 350                 d->flags |= DEVFL_GD_NOW;
 351         else
 352                 late = 1;
 353         spin_unlock_irqrestore(&d->lock, flags);
 354         if (late)
 355                 return;
 356
 357         mp = mempool_create(MIN_BUFS, mempool_alloc_slab, mempool_free_slab,
 358                 buf_pool_cache);
 359         if (mp == NULL) {
 360                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
 361                         d->aoemajor, d->aoeminor);
 362                 goto err;
 363         }
 364
 365         set = &d->tag_set;
 366         set->ops = &aoeblk_mq_ops;
 367         set->cmd_size = sizeof(struct aoe_req);
 368         set->nr_hw_queues = 1;
 369         set->queue_depth = 128;
 370         set->numa_node = NUMA_NO_NODE;
 371         set->flags = BLK_MQ_F_SHOULD_MERGE;
 372         err = blk_mq_alloc_tag_set(set);
 373         if (err) {
 374                 pr_err("aoe: cannot allocate tag set for %ld.%d\n",
 375                         d->aoemajor, d->aoeminor);
 376                 goto err_mempool;
 377         }
 378
 379         gd = blk_mq_alloc_disk(set, &lim, d);
 380         if (IS_ERR(gd)) {
 381                 pr_err("aoe: cannot allocate block queue for %ld.%d\n",
 382                         d->aoemajor, d->aoeminor);
 383                 goto err_tagset;
 384         }
 385
 386         spin_lock_irqsave(&d->lock, flags);
 387         WARN_ON(!(d->flags & DEVFL_GD_NOW));
 388         WARN_ON(!(d->flags & DEVFL_GDALLOC));
 389         WARN_ON(d->flags & DEVFL_TKILL);
 390         WARN_ON(d->gd);
 391         WARN_ON(d->flags & DEVFL_UP);
 392         d->bufpool = mp;
 393         d->blkq = gd->queue;
 394         d->gd = gd;
 395         gd->major = AOE_MAJOR;
 396         gd->first_minor = d->sysminor;
 397         gd->minors = AOE_PARTITIONS;
 398         gd->fops = &aoe_bdops;
 399         gd->private_data = d;
 400         ssize = d->ssize;
 401         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
 402                 d->aoemajor, d->aoeminor);
 403
 404         d->flags &= ~DEVFL_GDALLOC;
 405         d->flags |= DEVFL_UP;
 406
 407         spin_unlock_irqrestore(&d->lock, flags);
 408
 409         set_capacity(gd, ssize);
 410
 411         err = device_add_disk(NULL, gd, aoe_attr_groups);
 412         if (err)
 413                 goto out_disk_cleanup;
 414         aoedisk_add_debugfs(d);
 415
 416         spin_lock_irqsave(&d->lock, flags);
 417         WARN_ON(!(d->flags & DEVFL_GD_NOW));
 418         d->flags &= ~DEVFL_GD_NOW;
 419         spin_unlock_irqrestore(&d->lock, flags);
 420         return;
 421
 422 out_disk_cleanup:
 423         put_disk(gd);
 424 err_tagset:
 425         blk_mq_free_tag_set(set);
 426 err_mempool:
 427         mempool_destroy(mp);
 428 err:
 429         spin_lock_irqsave(&d->lock, flags);
 430         d->flags &= ~DEVFL_GD_NOW;
 431         queue_work(aoe_wq, &d->work);
 432         spin_unlock_irqrestore(&d->lock, flags);
 433 }
 434
 435 void
 436 aoeblk_exit(void)
 437 {
 438         debugfs_remove_recursive(aoe_debugfs_dir);
 439         aoe_debugfs_dir = NULL;
 440         kmem_cache_destroy(buf_pool_cache);
 441 }
 442
 443 int __init
 444 aoeblk_init(void)
 445 {
 446         buf_pool_cache = kmem_cache_create("aoe_bufs",
 447                                            sizeof(struct buf),
 448                                            0, 0, NULL);
 449         if (buf_pool_cache == NULL)
 450                 return -ENOMEM;
 451         aoe_debugfs_dir = debugfs_create_dir("aoe", NULL);
 452         return 0;
 453 }
 454