1 /* Copyright (c) 2007 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 "aoe.h" 20 21 static DEFINE_MUTEX(aoeblk_mutex); 22 static struct kmem_cache *buf_pool_cache; 23 24 static ssize_t aoedisk_show_state(struct device *dev, 25 struct device_attribute *attr, char *page) 26 { 27 struct gendisk *disk = dev_to_disk(dev); 28 struct aoedev *d = disk->private_data; 29 30 return snprintf(page, PAGE_SIZE, 31 "%s%s\n", 32 (d->flags & DEVFL_UP) ? "up" : "down", 33 (d->flags & DEVFL_KICKME) ? ",kickme" : 34 (d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : ""); 35 /* I'd rather see nopen exported so we can ditch closewait */ 36 } 37 static ssize_t aoedisk_show_mac(struct device *dev, 38 struct device_attribute *attr, char *page) 39 { 40 struct gendisk *disk = dev_to_disk(dev); 41 struct aoedev *d = disk->private_data; 42 struct aoetgt *t = d->targets[0]; 43 44 if (t == NULL) 45 return snprintf(page, PAGE_SIZE, "none\n"); 46 return snprintf(page, PAGE_SIZE, "%pm\n", t->addr); 47 } 48 static ssize_t aoedisk_show_netif(struct device *dev, 49 struct device_attribute *attr, char *page) 50 { 51 struct gendisk *disk = dev_to_disk(dev); 52 struct aoedev *d = disk->private_data; 53 struct net_device *nds[8], **nd, **nnd, **ne; 54 struct aoetgt **t, **te; 55 struct aoeif *ifp, *e; 56 char *p; 57 58 memset(nds, 0, sizeof nds); 59 nd = nds; 60 ne = nd + ARRAY_SIZE(nds); 61 t = d->targets; 62 te = t + NTARGETS; 63 for (; t < te && *t; t++) { 64 ifp = (*t)->ifs; 65 e = ifp + NAOEIFS; 66 for (; ifp < e && ifp->nd; ifp++) { 67 for (nnd = nds; nnd < nd; nnd++) 68 if (*nnd == ifp->nd) 69 break; 70 if (nnd == nd && nd != ne) 71 *nd++ = ifp->nd; 72 } 73 } 74 75 ne = nd; 76 nd = nds; 77 if (*nd == NULL) 78 return snprintf(page, PAGE_SIZE, "none\n"); 79 for (p = page; nd < ne; nd++) 80 p += snprintf(p, PAGE_SIZE - (p-page), "%s%s", 81 p == page ? "" : ",", (*nd)->name); 82 p += snprintf(p, PAGE_SIZE - (p-page), "\n"); 83 return p-page; 84 } 85 /* firmware version */ 86 static ssize_t aoedisk_show_fwver(struct device *dev, 87 struct device_attribute *attr, char *page) 88 { 89 struct gendisk *disk = dev_to_disk(dev); 90 struct aoedev *d = disk->private_data; 91 92 return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver); 93 } 94 95 static DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL); 96 static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL); 97 static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL); 98 static struct device_attribute dev_attr_firmware_version = { 99 .attr = { .name = "firmware-version", .mode = S_IRUGO }, 100 .show = aoedisk_show_fwver, 101 }; 102 103 static struct attribute *aoe_attrs[] = { 104 &dev_attr_state.attr, 105 &dev_attr_mac.attr, 106 &dev_attr_netif.attr, 107 &dev_attr_firmware_version.attr, 108 NULL, 109 }; 110 111 static const struct attribute_group attr_group = { 112 .attrs = aoe_attrs, 113 }; 114 115 static int 116 aoedisk_add_sysfs(struct aoedev *d) 117 { 118 return sysfs_create_group(&disk_to_dev(d->gd)->kobj, &attr_group); 119 } 120 void 121 aoedisk_rm_sysfs(struct aoedev *d) 122 { 123 sysfs_remove_group(&disk_to_dev(d->gd)->kobj, &attr_group); 124 } 125 126 static int 127 aoeblk_open(struct block_device *bdev, fmode_t mode) 128 { 129 struct aoedev *d = bdev->bd_disk->private_data; 130 ulong flags; 131 132 mutex_lock(&aoeblk_mutex); 133 spin_lock_irqsave(&d->lock, flags); 134 if (d->flags & DEVFL_UP) { 135 d->nopen++; 136 spin_unlock_irqrestore(&d->lock, flags); 137 mutex_unlock(&aoeblk_mutex); 138 return 0; 139 } 140 spin_unlock_irqrestore(&d->lock, flags); 141 mutex_unlock(&aoeblk_mutex); 142 return -ENODEV; 143 } 144 145 static int 146 aoeblk_release(struct gendisk *disk, fmode_t mode) 147 { 148 struct aoedev *d = disk->private_data; 149 ulong flags; 150 151 spin_lock_irqsave(&d->lock, flags); 152 153 if (--d->nopen == 0) { 154 spin_unlock_irqrestore(&d->lock, flags); 155 aoecmd_cfg(d->aoemajor, d->aoeminor); 156 return 0; 157 } 158 spin_unlock_irqrestore(&d->lock, flags); 159 160 return 0; 161 } 162 163 static void 164 aoeblk_make_request(struct request_queue *q, struct bio *bio) 165 { 166 struct sk_buff_head queue; 167 struct aoedev *d; 168 struct buf *buf; 169 ulong flags; 170 171 blk_queue_bounce(q, &bio); 172 173 if (bio == NULL) { 174 printk(KERN_ERR "aoe: bio is NULL\n"); 175 BUG(); 176 return; 177 } 178 d = bio->bi_bdev->bd_disk->private_data; 179 if (d == NULL) { 180 printk(KERN_ERR "aoe: bd_disk->private_data is NULL\n"); 181 BUG(); 182 bio_endio(bio, -ENXIO); 183 return; 184 } else if (bio->bi_io_vec == NULL) { 185 printk(KERN_ERR "aoe: bi_io_vec is NULL\n"); 186 BUG(); 187 bio_endio(bio, -ENXIO); 188 return; 189 } 190 buf = mempool_alloc(d->bufpool, GFP_NOIO); 191 if (buf == NULL) { 192 printk(KERN_INFO "aoe: buf allocation failure\n"); 193 bio_endio(bio, -ENOMEM); 194 return; 195 } 196 memset(buf, 0, sizeof(*buf)); 197 INIT_LIST_HEAD(&buf->bufs); 198 buf->stime = jiffies; 199 buf->bio = bio; 200 buf->resid = bio->bi_size; 201 buf->sector = bio->bi_sector; 202 buf->bv = &bio->bi_io_vec[bio->bi_idx]; 203 buf->bv_resid = buf->bv->bv_len; 204 WARN_ON(buf->bv_resid == 0); 205 buf->bv_off = buf->bv->bv_offset; 206 207 spin_lock_irqsave(&d->lock, flags); 208 209 if ((d->flags & DEVFL_UP) == 0) { 210 pr_info_ratelimited("aoe: device %ld.%d is not up\n", 211 d->aoemajor, d->aoeminor); 212 spin_unlock_irqrestore(&d->lock, flags); 213 mempool_free(buf, d->bufpool); 214 bio_endio(bio, -ENXIO); 215 return; 216 } 217 218 list_add_tail(&buf->bufs, &d->bufq); 219 220 aoecmd_work(d); 221 __skb_queue_head_init(&queue); 222 skb_queue_splice_init(&d->sendq, &queue); 223 224 spin_unlock_irqrestore(&d->lock, flags); 225 aoenet_xmit(&queue); 226 } 227 228 static int 229 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo) 230 { 231 struct aoedev *d = bdev->bd_disk->private_data; 232 233 if ((d->flags & DEVFL_UP) == 0) { 234 printk(KERN_ERR "aoe: disk not up\n"); 235 return -ENODEV; 236 } 237 238 geo->cylinders = d->geo.cylinders; 239 geo->heads = d->geo.heads; 240 geo->sectors = d->geo.sectors; 241 return 0; 242 } 243 244 static const struct block_device_operations aoe_bdops = { 245 .open = aoeblk_open, 246 .release = aoeblk_release, 247 .getgeo = aoeblk_getgeo, 248 .owner = THIS_MODULE, 249 }; 250 251 /* alloc_disk and add_disk can sleep */ 252 void 253 aoeblk_gdalloc(void *vp) 254 { 255 struct aoedev *d = vp; 256 struct gendisk *gd; 257 ulong flags; 258 259 gd = alloc_disk(AOE_PARTITIONS); 260 if (gd == NULL) { 261 printk(KERN_ERR 262 "aoe: cannot allocate disk structure for %ld.%d\n", 263 d->aoemajor, d->aoeminor); 264 goto err; 265 } 266 267 d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache); 268 if (d->bufpool == NULL) { 269 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n", 270 d->aoemajor, d->aoeminor); 271 goto err_disk; 272 } 273 274 d->blkq = blk_alloc_queue(GFP_KERNEL); 275 if (!d->blkq) 276 goto err_mempool; 277 blk_queue_make_request(d->blkq, aoeblk_make_request); 278 d->blkq->backing_dev_info.name = "aoe"; 279 if (bdi_init(&d->blkq->backing_dev_info)) 280 goto err_blkq; 281 spin_lock_irqsave(&d->lock, flags); 282 gd->major = AOE_MAJOR; 283 gd->first_minor = d->sysminor * AOE_PARTITIONS; 284 gd->fops = &aoe_bdops; 285 gd->private_data = d; 286 set_capacity(gd, d->ssize); 287 snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d", 288 d->aoemajor, d->aoeminor); 289 290 gd->queue = d->blkq; 291 d->gd = gd; 292 d->flags &= ~DEVFL_GDALLOC; 293 d->flags |= DEVFL_UP; 294 295 spin_unlock_irqrestore(&d->lock, flags); 296 297 add_disk(gd); 298 aoedisk_add_sysfs(d); 299 return; 300 301 err_blkq: 302 blk_cleanup_queue(d->blkq); 303 d->blkq = NULL; 304 err_mempool: 305 mempool_destroy(d->bufpool); 306 err_disk: 307 put_disk(gd); 308 err: 309 spin_lock_irqsave(&d->lock, flags); 310 d->flags &= ~DEVFL_GDALLOC; 311 spin_unlock_irqrestore(&d->lock, flags); 312 } 313 314 void 315 aoeblk_exit(void) 316 { 317 kmem_cache_destroy(buf_pool_cache); 318 } 319 320 int __init 321 aoeblk_init(void) 322 { 323 buf_pool_cache = kmem_cache_create("aoe_bufs", 324 sizeof(struct buf), 325 0, 0, NULL); 326 if (buf_pool_cache == NULL) 327 return -ENOMEM; 328 329 return 0; 330 } 331 332