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 <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 DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL);
 114 static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL);
 115 static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL);
 116 static struct device_attribute dev_attr_firmware_version = {
 117         .attr = { .name = "firmware-version", .mode = S_IRUGO },
 118         .show = aoedisk_show_fwver,
 119 };
 120 static DEVICE_ATTR(payload, S_IRUGO, aoedisk_show_payload, NULL);
 121
 122 static struct attribute *aoe_attrs[] = {
 123         &dev_attr_state.attr,
 124         &dev_attr_mac.attr,
 125         &dev_attr_netif.attr,
 126         &dev_attr_firmware_version.attr,
 127         &dev_attr_payload.attr,
 128         NULL,
 129 };
 130
 131 static const struct attribute_group attr_group = {
 132         .attrs = aoe_attrs,
 133 };
 134
 135 static int
 136 aoedisk_add_sysfs(struct aoedev *d)
 137 {
 138         return sysfs_create_group(&disk_to_dev(d->gd)->kobj, &attr_group);
 139 }
 140 void
 141 aoedisk_rm_sysfs(struct aoedev *d)
 142 {
 143         sysfs_remove_group(&disk_to_dev(d->gd)->kobj, &attr_group);
 144 }
 145
 146 static int
 147 aoeblk_open(struct block_device *bdev, fmode_t mode)
 148 {
 149         struct aoedev *d = bdev->bd_disk->private_data;
 150         ulong flags;
 151
 152         if (!virt_addr_valid(d)) {
 153                 pr_crit("aoe: invalid device pointer in %s\n",
 154                         __func__);
 155                 WARN_ON(1);
 156                 return -ENODEV;
 157         }
 158         if (!(d->flags & DEVFL_UP) || d->flags & DEVFL_TKILL)
 159                 return -ENODEV;
 160
 161         mutex_lock(&aoeblk_mutex);
 162         spin_lock_irqsave(&d->lock, flags);
 163         if (d->flags & DEVFL_UP && !(d->flags & DEVFL_TKILL)) {
 164                 d->nopen++;
 165                 spin_unlock_irqrestore(&d->lock, flags);
 166                 mutex_unlock(&aoeblk_mutex);
 167                 return 0;
 168         }
 169         spin_unlock_irqrestore(&d->lock, flags);
 170         mutex_unlock(&aoeblk_mutex);
 171         return -ENODEV;
 172 }
 173
 174 static void
 175 aoeblk_release(struct gendisk *disk, fmode_t mode)
 176 {
 177         struct aoedev *d = disk->private_data;
 178         ulong flags;
 179
 180         spin_lock_irqsave(&d->lock, flags);
 181
 182         if (--d->nopen == 0) {
 183                 spin_unlock_irqrestore(&d->lock, flags);
 184                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 185                 return;
 186         }
 187         spin_unlock_irqrestore(&d->lock, flags);
 188 }
 189
 190 static void
 191 aoeblk_request(struct request_queue *q)
 192 {
 193         struct aoedev *d;
 194         struct request *rq;
 195
 196         d = q->queuedata;
 197         if ((d->flags & DEVFL_UP) == 0) {
 198                 pr_info_ratelimited("aoe: device %ld.%d is not up\n",
 199                         d->aoemajor, d->aoeminor);
 200                 while ((rq = blk_peek_request(q))) {
 201                         blk_start_request(rq);
 202                         aoe_end_request(d, rq, 1);
 203                 }
 204                 return;
 205         }
 206         aoecmd_work(d);
 207 }
 208
 209 static int
 210 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 211 {
 212         struct aoedev *d = bdev->bd_disk->private_data;
 213
 214         if ((d->flags & DEVFL_UP) == 0) {
 215                 printk(KERN_ERR "aoe: disk not up\n");
 216                 return -ENODEV;
 217         }
 218
 219         geo->cylinders = d->geo.cylinders;
 220         geo->heads = d->geo.heads;
 221         geo->sectors = d->geo.sectors;
 222         return 0;
 223 }
 224
 225 static int
 226 aoeblk_ioctl(struct block_device *bdev, fmode_t mode, uint cmd, ulong arg)
 227 {
 228         struct aoedev *d;
 229
 230         if (!arg)
 231                 return -EINVAL;
 232
 233         d = bdev->bd_disk->private_data;
 234         if ((d->flags & DEVFL_UP) == 0) {
 235                 pr_err("aoe: disk not up\n");
 236                 return -ENODEV;
 237         }
 238
 239         if (cmd == HDIO_GET_IDENTITY) {
 240                 if (!copy_to_user((void __user *) arg, &d->ident,
 241                         sizeof(d->ident)))
 242                         return 0;
 243                 return -EFAULT;
 244         }
 245
 246         /* udev calls scsi_id, which uses SG_IO, resulting in noise */
 247         if (cmd != SG_IO)
 248                 pr_info("aoe: unknown ioctl 0x%x\n", cmd);
 249
 250         return -ENOTTY;
 251 }
 252
 253 static const struct block_device_operations aoe_bdops = {
 254         .open = aoeblk_open,
 255         .release = aoeblk_release,
 256         .ioctl = aoeblk_ioctl,
 257         .getgeo = aoeblk_getgeo,
 258         .owner = THIS_MODULE,
 259 };
 260
 261 /* alloc_disk and add_disk can sleep */
 262 void
 263 aoeblk_gdalloc(void *vp)
 264 {
 265         struct aoedev *d = vp;
 266         struct gendisk *gd;
 267         mempool_t *mp;
 268         struct request_queue *q;
 269         enum { KB = 1024, MB = KB * KB, READ_AHEAD = 2 * MB, };
 270         ulong flags;
 271         int late = 0;
 272
 273         spin_lock_irqsave(&d->lock, flags);
 274         if (d->flags & DEVFL_GDALLOC
 275         && !(d->flags & DEVFL_TKILL)
 276         && !(d->flags & DEVFL_GD_NOW))
 277                 d->flags |= DEVFL_GD_NOW;
 278         else
 279                 late = 1;
 280         spin_unlock_irqrestore(&d->lock, flags);
 281         if (late)
 282                 return;
 283
 284         gd = alloc_disk(AOE_PARTITIONS);
 285         if (gd == NULL) {
 286                 pr_err("aoe: cannot allocate disk structure for %ld.%d\n",
 287                         d->aoemajor, d->aoeminor);
 288                 goto err;
 289         }
 290
 291         mp = mempool_create(MIN_BUFS, mempool_alloc_slab, mempool_free_slab,
 292                 buf_pool_cache);
 293         if (mp == NULL) {
 294                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
 295                         d->aoemajor, d->aoeminor);
 296                 goto err_disk;
 297         }
 298         q = blk_init_queue(aoeblk_request, &d->lock);
 299         if (q == NULL) {
 300                 pr_err("aoe: cannot allocate block queue for %ld.%d\n",
 301                         d->aoemajor, d->aoeminor);
 302                 goto err_mempool;
 303         }
 304
 305         spin_lock_irqsave(&d->lock, flags);
 306         WARN_ON(!(d->flags & DEVFL_GD_NOW));
 307         WARN_ON(!(d->flags & DEVFL_GDALLOC));
 308         WARN_ON(d->flags & DEVFL_TKILL);
 309         WARN_ON(d->gd);
 310         WARN_ON(d->flags & DEVFL_UP);
 311         blk_queue_max_hw_sectors(q, BLK_DEF_MAX_SECTORS);
 312         q->backing_dev_info.name = "aoe";
 313         q->backing_dev_info.ra_pages = READ_AHEAD / PAGE_CACHE_SIZE;
 314         d->bufpool = mp;
 315         d->blkq = gd->queue = q;
 316         q->queuedata = d;
 317         d->gd = gd;
 318         if (aoe_maxsectors)
 319                 blk_queue_max_hw_sectors(q, aoe_maxsectors);
 320         gd->major = AOE_MAJOR;
 321         gd->first_minor = d->sysminor;
 322         gd->fops = &aoe_bdops;
 323         gd->private_data = d;
 324         set_capacity(gd, d->ssize);
 325         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
 326                 d->aoemajor, d->aoeminor);
 327
 328         d->flags &= ~DEVFL_GDALLOC;
 329         d->flags |= DEVFL_UP;
 330
 331         spin_unlock_irqrestore(&d->lock, flags);
 332
 333         add_disk(gd);
 334         aoedisk_add_sysfs(d);
 335
 336         spin_lock_irqsave(&d->lock, flags);
 337         WARN_ON(!(d->flags & DEVFL_GD_NOW));
 338         d->flags &= ~DEVFL_GD_NOW;
 339         spin_unlock_irqrestore(&d->lock, flags);
 340         return;
 341
 342 err_mempool:
 343         mempool_destroy(mp);
 344 err_disk:
 345         put_disk(gd);
 346 err:
 347         spin_lock_irqsave(&d->lock, flags);
 348         d->flags &= ~DEVFL_GD_NOW;
 349         schedule_work(&d->work);
 350         spin_unlock_irqrestore(&d->lock, flags);
 351 }
 352
 353 void
 354 aoeblk_exit(void)
 355 {
 356         debugfs_remove_recursive(aoe_debugfs_dir);
 357         aoe_debugfs_dir = NULL;
 358         kmem_cache_destroy(buf_pool_cache);
 359 }
 360
 361 int __init
 362 aoeblk_init(void)
 363 {
 364         buf_pool_cache = kmem_cache_create("aoe_bufs",
 365                                            sizeof(struct buf),
 366                                            0, 0, NULL);
 367         if (buf_pool_cache == NULL)
 368                 return -ENOMEM;
 369         aoe_debugfs_dir = debugfs_create_dir("aoe", NULL);
 370         if (IS_ERR_OR_NULL(aoe_debugfs_dir)) {
 371                 pr_info("aoe: cannot create debugfs directory\n");
 372                 aoe_debugfs_dir = NULL;
 373         }
 374         return 0;
 375 }
 376