drivers/block/aoe/aoeblk.c

   1 /* Copyright (c) 2012 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 <scsi/sg.h>
  21 #include "aoe.h"
  22
  23 static DEFINE_MUTEX(aoeblk_mutex);
  24 static struct kmem_cache *buf_pool_cache;
  25
  26 /* GPFS needs a larger value than the default. */
  27 static int aoe_maxsectors;
  28 module_param(aoe_maxsectors, int, 0644);
  29 MODULE_PARM_DESC(aoe_maxsectors,
  30         "When nonzero, set the maximum number of sectors per I/O request");
  31
  32 static ssize_t aoedisk_show_state(struct device *dev,
  33                                   struct device_attribute *attr, char *page)
  34 {
  35         struct gendisk *disk = dev_to_disk(dev);
  36         struct aoedev *d = disk->private_data;
  37
  38         return snprintf(page, PAGE_SIZE,
  39                         "%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 snprintf(page, PAGE_SIZE, "none\n");
  54         return snprintf(page, PAGE_SIZE, "%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 snprintf(page, PAGE_SIZE, "none\n");
  87         for (p = page; nd < ne; nd++)
  88                 p += snprintf(p, PAGE_SIZE - (p-page), "%s%s",
  89                         p == page ? "" : ",", (*nd)->name);
  90         p += snprintf(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 snprintf(page, PAGE_SIZE, "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 snprintf(page, PAGE_SIZE, "%lu\n", d->maxbcnt);
 109 }
 110
 111 static DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL);
 112 static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL);
 113 static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL);
 114 static struct device_attribute dev_attr_firmware_version = {
 115         .attr = { .name = "firmware-version", .mode = S_IRUGO },
 116         .show = aoedisk_show_fwver,
 117 };
 118 static DEVICE_ATTR(payload, S_IRUGO, aoedisk_show_payload, NULL);
 119
 120 static struct attribute *aoe_attrs[] = {
 121         &dev_attr_state.attr,
 122         &dev_attr_mac.attr,
 123         &dev_attr_netif.attr,
 124         &dev_attr_firmware_version.attr,
 125         &dev_attr_payload.attr,
 126         NULL,
 127 };
 128
 129 static const struct attribute_group attr_group = {
 130         .attrs = aoe_attrs,
 131 };
 132
 133 static int
 134 aoedisk_add_sysfs(struct aoedev *d)
 135 {
 136         return sysfs_create_group(&disk_to_dev(d->gd)->kobj, &attr_group);
 137 }
 138 void
 139 aoedisk_rm_sysfs(struct aoedev *d)
 140 {
 141         sysfs_remove_group(&disk_to_dev(d->gd)->kobj, &attr_group);
 142 }
 143
 144 static int
 145 aoeblk_open(struct block_device *bdev, fmode_t mode)
 146 {
 147         struct aoedev *d = bdev->bd_disk->private_data;
 148         ulong flags;
 149
 150         if (!virt_addr_valid(d)) {
 151                 pr_crit("aoe: invalid device pointer in %s\n",
 152                         __func__);
 153                 WARN_ON(1);
 154                 return -ENODEV;
 155         }
 156         if (!(d->flags & DEVFL_UP) || d->flags & DEVFL_TKILL)
 157                 return -ENODEV;
 158
 159         mutex_lock(&aoeblk_mutex);
 160         spin_lock_irqsave(&d->lock, flags);
 161         if (d->flags & DEVFL_UP && !(d->flags & DEVFL_TKILL)) {
 162                 d->nopen++;
 163                 spin_unlock_irqrestore(&d->lock, flags);
 164                 mutex_unlock(&aoeblk_mutex);
 165                 return 0;
 166         }
 167         spin_unlock_irqrestore(&d->lock, flags);
 168         mutex_unlock(&aoeblk_mutex);
 169         return -ENODEV;
 170 }
 171
 172 static void
 173 aoeblk_release(struct gendisk *disk, fmode_t mode)
 174 {
 175         struct aoedev *d = disk->private_data;
 176         ulong flags;
 177
 178         spin_lock_irqsave(&d->lock, flags);
 179
 180         if (--d->nopen == 0) {
 181                 spin_unlock_irqrestore(&d->lock, flags);
 182                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 183                 return;
 184         }
 185         spin_unlock_irqrestore(&d->lock, flags);
 186 }
 187
 188 static void
 189 aoeblk_request(struct request_queue *q)
 190 {
 191         struct aoedev *d;
 192         struct request *rq;
 193
 194         d = q->queuedata;
 195         if ((d->flags & DEVFL_UP) == 0) {
 196                 pr_info_ratelimited("aoe: device %ld.%d is not up\n",
 197                         d->aoemajor, d->aoeminor);
 198                 while ((rq = blk_peek_request(q))) {
 199                         blk_start_request(rq);
 200                         aoe_end_request(d, rq, 1);
 201                 }
 202                 return;
 203         }
 204         aoecmd_work(d);
 205 }
 206
 207 static int
 208 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 209 {
 210         struct aoedev *d = bdev->bd_disk->private_data;
 211
 212         if ((d->flags & DEVFL_UP) == 0) {
 213                 printk(KERN_ERR "aoe: disk not up\n");
 214                 return -ENODEV;
 215         }
 216
 217         geo->cylinders = d->geo.cylinders;
 218         geo->heads = d->geo.heads;
 219         geo->sectors = d->geo.sectors;
 220         return 0;
 221 }
 222
 223 static int
 224 aoeblk_ioctl(struct block_device *bdev, fmode_t mode, uint cmd, ulong arg)
 225 {
 226         struct aoedev *d;
 227
 228         if (!arg)
 229                 return -EINVAL;
 230
 231         d = bdev->bd_disk->private_data;
 232         if ((d->flags & DEVFL_UP) == 0) {
 233                 pr_err("aoe: disk not up\n");
 234                 return -ENODEV;
 235         }
 236
 237         if (cmd == HDIO_GET_IDENTITY) {
 238                 if (!copy_to_user((void __user *) arg, &d->ident,
 239                         sizeof(d->ident)))
 240                         return 0;
 241                 return -EFAULT;
 242         }
 243
 244         /* udev calls scsi_id, which uses SG_IO, resulting in noise */
 245         if (cmd != SG_IO)
 246                 pr_info("aoe: unknown ioctl 0x%x\n", cmd);
 247
 248         return -ENOTTY;
 249 }
 250
 251 static const struct block_device_operations aoe_bdops = {
 252         .open = aoeblk_open,
 253         .release = aoeblk_release,
 254         .ioctl = aoeblk_ioctl,
 255         .getgeo = aoeblk_getgeo,
 256         .owner = THIS_MODULE,
 257 };
 258
 259 /* alloc_disk and add_disk can sleep */
 260 void
 261 aoeblk_gdalloc(void *vp)
 262 {
 263         struct aoedev *d = vp;
 264         struct gendisk *gd;
 265         mempool_t *mp;
 266         struct request_queue *q;
 267         enum { KB = 1024, MB = KB * KB, READ_AHEAD = 2 * MB, };
 268         ulong flags;
 269         int late = 0;
 270
 271         spin_lock_irqsave(&d->lock, flags);
 272         if (d->flags & DEVFL_GDALLOC
 273         && !(d->flags & DEVFL_TKILL)
 274         && !(d->flags & DEVFL_GD_NOW))
 275                 d->flags |= DEVFL_GD_NOW;
 276         else
 277                 late = 1;
 278         spin_unlock_irqrestore(&d->lock, flags);
 279         if (late)
 280                 return;
 281
 282         gd = alloc_disk(AOE_PARTITIONS);
 283         if (gd == NULL) {
 284                 pr_err("aoe: cannot allocate disk structure for %ld.%d\n",
 285                         d->aoemajor, d->aoeminor);
 286                 goto err;
 287         }
 288
 289         mp = mempool_create(MIN_BUFS, mempool_alloc_slab, mempool_free_slab,
 290                 buf_pool_cache);
 291         if (mp == NULL) {
 292                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
 293                         d->aoemajor, d->aoeminor);
 294                 goto err_disk;
 295         }
 296         q = blk_init_queue(aoeblk_request, &d->lock);
 297         if (q == NULL) {
 298                 pr_err("aoe: cannot allocate block queue for %ld.%d\n",
 299                         d->aoemajor, d->aoeminor);
 300                 goto err_mempool;
 301         }
 302
 303         spin_lock_irqsave(&d->lock, flags);
 304         WARN_ON(!(d->flags & DEVFL_GD_NOW));
 305         WARN_ON(!(d->flags & DEVFL_GDALLOC));
 306         WARN_ON(d->flags & DEVFL_TKILL);
 307         WARN_ON(d->gd);
 308         WARN_ON(d->flags & DEVFL_UP);
 309         blk_queue_max_hw_sectors(q, BLK_DEF_MAX_SECTORS);
 310         q->backing_dev_info.name = "aoe";
 311         q->backing_dev_info.ra_pages = READ_AHEAD / PAGE_CACHE_SIZE;
 312         d->bufpool = mp;
 313         d->blkq = gd->queue = q;
 314         q->queuedata = d;
 315         d->gd = gd;
 316         if (aoe_maxsectors)
 317                 blk_queue_max_hw_sectors(q, aoe_maxsectors);
 318         gd->major = AOE_MAJOR;
 319         gd->first_minor = d->sysminor;
 320         gd->fops = &aoe_bdops;
 321         gd->private_data = d;
 322         set_capacity(gd, d->ssize);
 323         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
 324                 d->aoemajor, d->aoeminor);
 325
 326         d->flags &= ~DEVFL_GDALLOC;
 327         d->flags |= DEVFL_UP;
 328
 329         spin_unlock_irqrestore(&d->lock, flags);
 330
 331         add_disk(gd);
 332         aoedisk_add_sysfs(d);
 333
 334         spin_lock_irqsave(&d->lock, flags);
 335         WARN_ON(!(d->flags & DEVFL_GD_NOW));
 336         d->flags &= ~DEVFL_GD_NOW;
 337         spin_unlock_irqrestore(&d->lock, flags);
 338         return;
 339
 340 err_mempool:
 341         mempool_destroy(mp);
 342 err_disk:
 343         put_disk(gd);
 344 err:
 345         spin_lock_irqsave(&d->lock, flags);
 346         d->flags &= ~DEVFL_GD_NOW;
 347         schedule_work(&d->work);
 348         spin_unlock_irqrestore(&d->lock, flags);
 349 }
 350
 351 void
 352 aoeblk_exit(void)
 353 {
 354         kmem_cache_destroy(buf_pool_cache);
 355 }
 356
 357 int __init
 358 aoeblk_init(void)
 359 {
 360         buf_pool_cache = kmem_cache_create("aoe_bufs",
 361                                            sizeof(struct buf),
 362                                            0, 0, NULL);
 363         if (buf_pool_cache == NULL)
 364                 return -ENOMEM;
 365
 366         return 0;
 367 }
 368