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/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_CACHE_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