drivers/block/aoe/aoeblk.c

   1 /* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
   2 /*
   3  * aoeblk.c
   4  * block device routines
   5  */
   6
   7 #include <linux/hdreg.h>
   8 #include <linux/blkdev.h>
   9 #include <linux/backing-dev.h>
  10 #include <linux/fs.h>
  11 #include <linux/ioctl.h>
  12 #include <linux/genhd.h>
  13 #include <linux/netdevice.h>
  14 #include "aoe.h"
  15
  16 static struct kmem_cache *buf_pool_cache;
  17
  18 static ssize_t aoedisk_show_state(struct device *dev,
  19                                   struct device_attribute *attr, char *page)
  20 {
  21         struct gendisk *disk = dev_to_disk(dev);
  22         struct aoedev *d = disk->private_data;
  23
  24         return snprintf(page, PAGE_SIZE,
  25                         "%s%s\n",
  26                         (d->flags & DEVFL_UP) ? "up" : "down",
  27                         (d->flags & DEVFL_KICKME) ? ",kickme" :
  28                         (d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
  29         /* I'd rather see nopen exported so we can ditch closewait */
  30 }
  31 static ssize_t aoedisk_show_mac(struct device *dev,
  32                                 struct device_attribute *attr, char *page)
  33 {
  34         struct gendisk *disk = dev_to_disk(dev);
  35         struct aoedev *d = disk->private_data;
  36         struct aoetgt *t = d->targets[0];
  37
  38         if (t == NULL)
  39                 return snprintf(page, PAGE_SIZE, "none\n");
  40         return snprintf(page, PAGE_SIZE, "%pm\n", t->addr);
  41 }
  42 static ssize_t aoedisk_show_netif(struct device *dev,
  43                                   struct device_attribute *attr, char *page)
  44 {
  45         struct gendisk *disk = dev_to_disk(dev);
  46         struct aoedev *d = disk->private_data;
  47         struct net_device *nds[8], **nd, **nnd, **ne;
  48         struct aoetgt **t, **te;
  49         struct aoeif *ifp, *e;
  50         char *p;
  51
  52         memset(nds, 0, sizeof nds);
  53         nd = nds;
  54         ne = nd + ARRAY_SIZE(nds);
  55         t = d->targets;
  56         te = t + NTARGETS;
  57         for (; t < te && *t; t++) {
  58                 ifp = (*t)->ifs;
  59                 e = ifp + NAOEIFS;
  60                 for (; ifp < e && ifp->nd; ifp++) {
  61                         for (nnd = nds; nnd < nd; nnd++)
  62                                 if (*nnd == ifp->nd)
  63                                         break;
  64                         if (nnd == nd && nd != ne)
  65                                 *nd++ = ifp->nd;
  66                 }
  67         }
  68
  69         ne = nd;
  70         nd = nds;
  71         if (*nd == NULL)
  72                 return snprintf(page, PAGE_SIZE, "none\n");
  73         for (p = page; nd < ne; nd++)
  74                 p += snprintf(p, PAGE_SIZE - (p-page), "%s%s",
  75                         p == page ? "" : ",", (*nd)->name);
  76         p += snprintf(p, PAGE_SIZE - (p-page), "\n");
  77         return p-page;
  78 }
  79 /* firmware version */
  80 static ssize_t aoedisk_show_fwver(struct device *dev,
  81                                   struct device_attribute *attr, char *page)
  82 {
  83         struct gendisk *disk = dev_to_disk(dev);
  84         struct aoedev *d = disk->private_data;
  85
  86         return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
  87 }
  88
  89 static DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL);
  90 static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL);
  91 static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL);
  92 static struct device_attribute dev_attr_firmware_version = {
  93         .attr = { .name = "firmware-version", .mode = S_IRUGO },
  94         .show = aoedisk_show_fwver,
  95 };
  96
  97 static struct attribute *aoe_attrs[] = {
  98         &dev_attr_state.attr,
  99         &dev_attr_mac.attr,
 100         &dev_attr_netif.attr,
 101         &dev_attr_firmware_version.attr,
 102         NULL,
 103 };
 104
 105 static const struct attribute_group attr_group = {
 106         .attrs = aoe_attrs,
 107 };
 108
 109 static int
 110 aoedisk_add_sysfs(struct aoedev *d)
 111 {
 112         return sysfs_create_group(&disk_to_dev(d->gd)->kobj, &attr_group);
 113 }
 114 void
 115 aoedisk_rm_sysfs(struct aoedev *d)
 116 {
 117         sysfs_remove_group(&disk_to_dev(d->gd)->kobj, &attr_group);
 118 }
 119
 120 static int
 121 aoeblk_open(struct block_device *bdev, fmode_t mode)
 122 {
 123         struct aoedev *d = bdev->bd_disk->private_data;
 124         ulong flags;
 125
 126         spin_lock_irqsave(&d->lock, flags);
 127         if (d->flags & DEVFL_UP) {
 128                 d->nopen++;
 129                 spin_unlock_irqrestore(&d->lock, flags);
 130                 return 0;
 131         }
 132         spin_unlock_irqrestore(&d->lock, flags);
 133         return -ENODEV;
 134 }
 135
 136 static int
 137 aoeblk_release(struct gendisk *disk, fmode_t mode)
 138 {
 139         struct aoedev *d = disk->private_data;
 140         ulong flags;
 141
 142         spin_lock_irqsave(&d->lock, flags);
 143
 144         if (--d->nopen == 0) {
 145                 spin_unlock_irqrestore(&d->lock, flags);
 146                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 147                 return 0;
 148         }
 149         spin_unlock_irqrestore(&d->lock, flags);
 150
 151         return 0;
 152 }
 153
 154 static int
 155 aoeblk_make_request(struct request_queue *q, struct bio *bio)
 156 {
 157         struct sk_buff_head queue;
 158         struct aoedev *d;
 159         struct buf *buf;
 160         ulong flags;
 161
 162         blk_queue_bounce(q, &bio);
 163
 164         if (bio == NULL) {
 165                 printk(KERN_ERR "aoe: bio is NULL\n");
 166                 BUG();
 167                 return 0;
 168         }
 169         d = bio->bi_bdev->bd_disk->private_data;
 170         if (d == NULL) {
 171                 printk(KERN_ERR "aoe: bd_disk->private_data is NULL\n");
 172                 BUG();
 173                 bio_endio(bio, -ENXIO);
 174                 return 0;
 175         } else if (bio_rw_flagged(bio, BIO_RW_BARRIER)) {
 176                 bio_endio(bio, -EOPNOTSUPP);
 177                 return 0;
 178         } else if (bio->bi_io_vec == NULL) {
 179                 printk(KERN_ERR "aoe: bi_io_vec is NULL\n");
 180                 BUG();
 181                 bio_endio(bio, -ENXIO);
 182                 return 0;
 183         }
 184         buf = mempool_alloc(d->bufpool, GFP_NOIO);
 185         if (buf == NULL) {
 186                 printk(KERN_INFO "aoe: buf allocation failure\n");
 187                 bio_endio(bio, -ENOMEM);
 188                 return 0;
 189         }
 190         memset(buf, 0, sizeof(*buf));
 191         INIT_LIST_HEAD(&buf->bufs);
 192         buf->stime = jiffies;
 193         buf->bio = bio;
 194         buf->resid = bio->bi_size;
 195         buf->sector = bio->bi_sector;
 196         buf->bv = &bio->bi_io_vec[bio->bi_idx];
 197         buf->bv_resid = buf->bv->bv_len;
 198         WARN_ON(buf->bv_resid == 0);
 199         buf->bv_off = buf->bv->bv_offset;
 200
 201         spin_lock_irqsave(&d->lock, flags);
 202
 203         if ((d->flags & DEVFL_UP) == 0) {
 204                 printk(KERN_INFO "aoe: device %ld.%d is not up\n",
 205                         d->aoemajor, d->aoeminor);
 206                 spin_unlock_irqrestore(&d->lock, flags);
 207                 mempool_free(buf, d->bufpool);
 208                 bio_endio(bio, -ENXIO);
 209                 return 0;
 210         }
 211
 212         list_add_tail(&buf->bufs, &d->bufq);
 213
 214         aoecmd_work(d);
 215         __skb_queue_head_init(&queue);
 216         skb_queue_splice_init(&d->sendq, &queue);
 217
 218         spin_unlock_irqrestore(&d->lock, flags);
 219         aoenet_xmit(&queue);
 220
 221         return 0;
 222 }
 223
 224 static int
 225 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 226 {
 227         struct aoedev *d = bdev->bd_disk->private_data;
 228
 229         if ((d->flags & DEVFL_UP) == 0) {
 230                 printk(KERN_ERR "aoe: disk not up\n");
 231                 return -ENODEV;
 232         }
 233
 234         geo->cylinders = d->geo.cylinders;
 235         geo->heads = d->geo.heads;
 236         geo->sectors = d->geo.sectors;
 237         return 0;
 238 }
 239
 240 static const struct block_device_operations aoe_bdops = {
 241         .open = aoeblk_open,
 242         .release = aoeblk_release,
 243         .getgeo = aoeblk_getgeo,
 244         .owner = THIS_MODULE,
 245 };
 246
 247 /* alloc_disk and add_disk can sleep */
 248 void
 249 aoeblk_gdalloc(void *vp)
 250 {
 251         struct aoedev *d = vp;
 252         struct gendisk *gd;
 253         ulong flags;
 254
 255         gd = alloc_disk(AOE_PARTITIONS);
 256         if (gd == NULL) {
 257                 printk(KERN_ERR
 258                         "aoe: cannot allocate disk structure for %ld.%d\n",
 259                         d->aoemajor, d->aoeminor);
 260                 goto err;
 261         }
 262
 263         d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache);
 264         if (d->bufpool == NULL) {
 265                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
 266                         d->aoemajor, d->aoeminor);
 267                 goto err_disk;
 268         }
 269
 270         d->blkq = blk_alloc_queue(GFP_KERNEL);
 271         if (!d->blkq)
 272                 goto err_mempool;
 273         blk_queue_make_request(d->blkq, aoeblk_make_request);
 274         d->blkq->backing_dev_info.name = "aoe";
 275         if (bdi_init(&d->blkq->backing_dev_info))
 276                 goto err_blkq;
 277         spin_lock_irqsave(&d->lock, flags);
 278         gd->major = AOE_MAJOR;
 279         gd->first_minor = d->sysminor * AOE_PARTITIONS;
 280         gd->fops = &aoe_bdops;
 281         gd->private_data = d;
 282         set_capacity(gd, d->ssize);
 283         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
 284                 d->aoemajor, d->aoeminor);
 285
 286         gd->queue = d->blkq;
 287         d->gd = gd;
 288         d->flags &= ~DEVFL_GDALLOC;
 289         d->flags |= DEVFL_UP;
 290
 291         spin_unlock_irqrestore(&d->lock, flags);
 292
 293         add_disk(gd);
 294         aoedisk_add_sysfs(d);
 295         return;
 296
 297 err_blkq:
 298         blk_cleanup_queue(d->blkq);
 299         d->blkq = NULL;
 300 err_mempool:
 301         mempool_destroy(d->bufpool);
 302 err_disk:
 303         put_disk(gd);
 304 err:
 305         spin_lock_irqsave(&d->lock, flags);
 306         d->flags &= ~DEVFL_GDALLOC;
 307         spin_unlock_irqrestore(&d->lock, flags);
 308 }
 309
 310 void
 311 aoeblk_exit(void)
 312 {
 313         kmem_cache_destroy(buf_pool_cache);
 314 }
 315
 316 int __init
 317 aoeblk_init(void)
 318 {
 319         buf_pool_cache = kmem_cache_create("aoe_bufs",
 320                                            sizeof(struct buf),
 321                                            0, 0, NULL);
 322         if (buf_pool_cache == NULL)
 323                 return -ENOMEM;
 324
 325         return 0;
 326 }
 327