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, "%012llx\n", mac_addr(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, .owner = THIS_MODULE },
  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(&d->gd->dev.kobj, &attr_group);
 113 }
 114 void
 115 aoedisk_rm_sysfs(struct aoedev *d)
 116 {
 117         sysfs_remove_group(&d->gd->dev.kobj, &attr_group);
 118 }
 119
 120 static int
 121 aoeblk_open(struct inode *inode, struct file *filp)
 122 {
 123         struct aoedev *d;
 124         ulong flags;
 125
 126         d = inode->i_bdev->bd_disk->private_data;
 127
 128         spin_lock_irqsave(&d->lock, flags);
 129         if (d->flags & DEVFL_UP) {
 130                 d->nopen++;
 131                 spin_unlock_irqrestore(&d->lock, flags);
 132                 return 0;
 133         }
 134         spin_unlock_irqrestore(&d->lock, flags);
 135         return -ENODEV;
 136 }
 137
 138 static int
 139 aoeblk_release(struct inode *inode, struct file *filp)
 140 {
 141         struct aoedev *d;
 142         ulong flags;
 143
 144         d = inode->i_bdev->bd_disk->private_data;
 145
 146         spin_lock_irqsave(&d->lock, flags);
 147
 148         if (--d->nopen == 0) {
 149                 spin_unlock_irqrestore(&d->lock, flags);
 150                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 151                 return 0;
 152         }
 153         spin_unlock_irqrestore(&d->lock, flags);
 154
 155         return 0;
 156 }
 157
 158 static int
 159 aoeblk_make_request(struct request_queue *q, struct bio *bio)
 160 {
 161         struct aoedev *d;
 162         struct buf *buf;
 163         struct sk_buff *sl;
 164         ulong flags;
 165
 166         blk_queue_bounce(q, &bio);
 167
 168         if (bio == NULL) {
 169                 printk(KERN_ERR "aoe: bio is NULL\n");
 170                 BUG();
 171                 return 0;
 172         }
 173         d = bio->bi_bdev->bd_disk->private_data;
 174         if (d == NULL) {
 175                 printk(KERN_ERR "aoe: bd_disk->private_data is NULL\n");
 176                 BUG();
 177                 bio_endio(bio, -ENXIO);
 178                 return 0;
 179         } else if (bio->bi_io_vec == NULL) {
 180                 printk(KERN_ERR "aoe: bi_io_vec is NULL\n");
 181                 BUG();
 182                 bio_endio(bio, -ENXIO);
 183                 return 0;
 184         }
 185         buf = mempool_alloc(d->bufpool, GFP_NOIO);
 186         if (buf == NULL) {
 187                 printk(KERN_INFO "aoe: buf allocation failure\n");
 188                 bio_endio(bio, -ENOMEM);
 189                 return 0;
 190         }
 191         memset(buf, 0, sizeof(*buf));
 192         INIT_LIST_HEAD(&buf->bufs);
 193         buf->stime = jiffies;
 194         buf->bio = bio;
 195         buf->resid = bio->bi_size;
 196         buf->sector = bio->bi_sector;
 197         buf->bv = &bio->bi_io_vec[bio->bi_idx];
 198         buf->bv_resid = buf->bv->bv_len;
 199         WARN_ON(buf->bv_resid == 0);
 200         buf->bv_off = buf->bv->bv_offset;
 201
 202         spin_lock_irqsave(&d->lock, flags);
 203
 204         if ((d->flags & DEVFL_UP) == 0) {
 205                 printk(KERN_INFO "aoe: device %ld.%d is not up\n",
 206                         d->aoemajor, d->aoeminor);
 207                 spin_unlock_irqrestore(&d->lock, flags);
 208                 mempool_free(buf, d->bufpool);
 209                 bio_endio(bio, -ENXIO);
 210                 return 0;
 211         }
 212
 213         list_add_tail(&buf->bufs, &d->bufq);
 214
 215         aoecmd_work(d);
 216         sl = d->sendq_hd;
 217         d->sendq_hd = d->sendq_tl = NULL;
 218
 219         spin_unlock_irqrestore(&d->lock, flags);
 220         aoenet_xmit(sl);
 221
 222         return 0;
 223 }
 224
 225 static int
 226 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 227 {
 228         struct aoedev *d = bdev->bd_disk->private_data;
 229
 230         if ((d->flags & DEVFL_UP) == 0) {
 231                 printk(KERN_ERR "aoe: disk not up\n");
 232                 return -ENODEV;
 233         }
 234
 235         geo->cylinders = d->geo.cylinders;
 236         geo->heads = d->geo.heads;
 237         geo->sectors = d->geo.sectors;
 238         return 0;
 239 }
 240
 241 static struct block_device_operations aoe_bdops = {
 242         .open = aoeblk_open,
 243         .release = aoeblk_release,
 244         .getgeo = aoeblk_getgeo,
 245         .owner = THIS_MODULE,
 246 };
 247
 248 /* alloc_disk and add_disk can sleep */
 249 void
 250 aoeblk_gdalloc(void *vp)
 251 {
 252         struct aoedev *d = vp;
 253         struct gendisk *gd;
 254         ulong flags;
 255
 256         gd = alloc_disk(AOE_PARTITIONS);
 257         if (gd == NULL) {
 258                 printk(KERN_ERR
 259                         "aoe: cannot allocate disk structure for %ld.%d\n",
 260                         d->aoemajor, d->aoeminor);
 261                 goto err;
 262         }
 263
 264         d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache);
 265         if (d->bufpool == NULL) {
 266                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
 267                         d->aoemajor, d->aoeminor);
 268                 goto err_disk;
 269         }
 270
 271         blk_queue_make_request(&d->blkq, aoeblk_make_request);
 272         if (bdi_init(&d->blkq.backing_dev_info))
 273                 goto err_mempool;
 274         spin_lock_irqsave(&d->lock, flags);
 275         gd->major = AOE_MAJOR;
 276         gd->first_minor = d->sysminor * AOE_PARTITIONS;
 277         gd->fops = &aoe_bdops;
 278         gd->private_data = d;
 279         gd->capacity = d->ssize;
 280         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
 281                 d->aoemajor, d->aoeminor);
 282
 283         gd->queue = &d->blkq;
 284         d->gd = gd;
 285         d->flags &= ~DEVFL_GDALLOC;
 286         d->flags |= DEVFL_UP;
 287
 288         spin_unlock_irqrestore(&d->lock, flags);
 289
 290         add_disk(gd);
 291         aoedisk_add_sysfs(d);
 292         return;
 293
 294 err_mempool:
 295         mempool_destroy(d->bufpool);
 296 err_disk:
 297         put_disk(gd);
 298 err:
 299         spin_lock_irqsave(&d->lock, flags);
 300         d->flags &= ~DEVFL_GDALLOC;
 301         spin_unlock_irqrestore(&d->lock, flags);
 302 }
 303
 304 void
 305 aoeblk_exit(void)
 306 {
 307         kmem_cache_destroy(buf_pool_cache);
 308 }
 309
 310 int __init
 311 aoeblk_init(void)
 312 {
 313         buf_pool_cache = kmem_cache_create("aoe_bufs",
 314                                            sizeof(struct buf),
 315                                            0, 0, NULL);
 316         if (buf_pool_cache == NULL)
 317                 return -ENOMEM;
 318
 319         return 0;
 320 }
 321