drivers/block/aoe/aoeblk.c

   1 /* Copyright (c) 2006 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_PAUSE) ? ",paused" :
  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
  37         return snprintf(page, PAGE_SIZE, "%012llx\n",
  38                         (unsigned long long)mac_addr(d->addr));
  39 }
  40 static ssize_t aoedisk_show_netif(struct device *dev,
  41                                   struct device_attribute *attr, char *page)
  42 {
  43         struct gendisk *disk = dev_to_disk(dev);
  44         struct aoedev *d = disk->private_data;
  45
  46         return snprintf(page, PAGE_SIZE, "%s\n", d->ifp->name);
  47 }
  48 /* firmware version */
  49 static ssize_t aoedisk_show_fwver(struct device *dev,
  50                                   struct device_attribute *attr, char *page)
  51 {
  52         struct gendisk *disk = dev_to_disk(dev);
  53         struct aoedev *d = disk->private_data;
  54
  55         return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
  56 }
  57
  58 static DEVICE_ATTR(state, S_IRUGO, aoedisk_show_state, NULL);
  59 static DEVICE_ATTR(mac, S_IRUGO, aoedisk_show_mac, NULL);
  60 static DEVICE_ATTR(netif, S_IRUGO, aoedisk_show_netif, NULL);
  61 static struct device_attribute dev_attr_firmware_version = {
  62         .attr = { .name = "firmware-version", .mode = S_IRUGO, .owner = THIS_MODULE },
  63         .show = aoedisk_show_fwver,
  64 };
  65
  66 static struct attribute *aoe_attrs[] = {
  67         &dev_attr_state.attr,
  68         &dev_attr_mac.attr,
  69         &dev_attr_netif.attr,
  70         &dev_attr_firmware_version.attr,
  71         NULL,
  72 };
  73
  74 static const struct attribute_group attr_group = {
  75         .attrs = aoe_attrs,
  76 };
  77
  78 static int
  79 aoedisk_add_sysfs(struct aoedev *d)
  80 {
  81         return sysfs_create_group(&d->gd->dev.kobj, &attr_group);
  82 }
  83 void
  84 aoedisk_rm_sysfs(struct aoedev *d)
  85 {
  86         sysfs_remove_group(&d->gd->dev.kobj, &attr_group);
  87 }
  88
  89 static int
  90 aoeblk_open(struct inode *inode, struct file *filp)
  91 {
  92         struct aoedev *d;
  93         ulong flags;
  94
  95         d = inode->i_bdev->bd_disk->private_data;
  96
  97         spin_lock_irqsave(&d->lock, flags);
  98         if (d->flags & DEVFL_UP) {
  99                 d->nopen++;
 100                 spin_unlock_irqrestore(&d->lock, flags);
 101                 return 0;
 102         }
 103         spin_unlock_irqrestore(&d->lock, flags);
 104         return -ENODEV;
 105 }
 106
 107 static int
 108 aoeblk_release(struct inode *inode, struct file *filp)
 109 {
 110         struct aoedev *d;
 111         ulong flags;
 112
 113         d = inode->i_bdev->bd_disk->private_data;
 114
 115         spin_lock_irqsave(&d->lock, flags);
 116
 117         if (--d->nopen == 0) {
 118                 spin_unlock_irqrestore(&d->lock, flags);
 119                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 120                 return 0;
 121         }
 122         spin_unlock_irqrestore(&d->lock, flags);
 123
 124         return 0;
 125 }
 126
 127 static int
 128 aoeblk_make_request(struct request_queue *q, struct bio *bio)
 129 {
 130         struct aoedev *d;
 131         struct buf *buf;
 132         struct sk_buff *sl;
 133         ulong flags;
 134
 135         blk_queue_bounce(q, &bio);
 136
 137         d = bio->bi_bdev->bd_disk->private_data;
 138         buf = mempool_alloc(d->bufpool, GFP_NOIO);
 139         if (buf == NULL) {
 140                 printk(KERN_INFO "aoe: buf allocation failure\n");
 141                 bio_endio(bio, -ENOMEM);
 142                 return 0;
 143         }
 144         memset(buf, 0, sizeof(*buf));
 145         INIT_LIST_HEAD(&buf->bufs);
 146         buf->start_time = jiffies;
 147         buf->bio = bio;
 148         buf->resid = bio->bi_size;
 149         buf->sector = bio->bi_sector;
 150         buf->bv = &bio->bi_io_vec[bio->bi_idx];
 151         WARN_ON(buf->bv->bv_len == 0);
 152         buf->bv_resid = buf->bv->bv_len;
 153         buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
 154
 155         spin_lock_irqsave(&d->lock, flags);
 156
 157         if ((d->flags & DEVFL_UP) == 0) {
 158                 printk(KERN_INFO "aoe: device %ld.%ld is not up\n",
 159                         d->aoemajor, d->aoeminor);
 160                 spin_unlock_irqrestore(&d->lock, flags);
 161                 mempool_free(buf, d->bufpool);
 162                 bio_endio(bio, -ENXIO);
 163                 return 0;
 164         }
 165
 166         list_add_tail(&buf->bufs, &d->bufq);
 167
 168         aoecmd_work(d);
 169         sl = d->sendq_hd;
 170         d->sendq_hd = d->sendq_tl = NULL;
 171
 172         spin_unlock_irqrestore(&d->lock, flags);
 173         aoenet_xmit(sl);
 174
 175         return 0;
 176 }
 177
 178 static int
 179 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 180 {
 181         struct aoedev *d = bdev->bd_disk->private_data;
 182
 183         if ((d->flags & DEVFL_UP) == 0) {
 184                 printk(KERN_ERR "aoe: disk not up\n");
 185                 return -ENODEV;
 186         }
 187
 188         geo->cylinders = d->geo.cylinders;
 189         geo->heads = d->geo.heads;
 190         geo->sectors = d->geo.sectors;
 191         return 0;
 192 }
 193
 194 static struct block_device_operations aoe_bdops = {
 195         .open = aoeblk_open,
 196         .release = aoeblk_release,
 197         .getgeo = aoeblk_getgeo,
 198         .owner = THIS_MODULE,
 199 };
 200
 201 /* alloc_disk and add_disk can sleep */
 202 void
 203 aoeblk_gdalloc(void *vp)
 204 {
 205         struct aoedev *d = vp;
 206         struct gendisk *gd;
 207         ulong flags;
 208
 209         gd = alloc_disk(AOE_PARTITIONS);
 210         if (gd == NULL) {
 211                 printk(KERN_ERR "aoe: cannot allocate disk structure for %ld.%ld\n",
 212                         d->aoemajor, d->aoeminor);
 213                 goto err;
 214         }
 215
 216         d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache);
 217         if (d->bufpool == NULL) {
 218                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%ld\n",
 219                         d->aoemajor, d->aoeminor);
 220                 goto err_disk;
 221         }
 222
 223         blk_queue_make_request(&d->blkq, aoeblk_make_request);
 224         if (bdi_init(&d->blkq.backing_dev_info))
 225                 goto err_mempool;
 226         spin_lock_irqsave(&d->lock, flags);
 227         gd->major = AOE_MAJOR;
 228         gd->first_minor = d->sysminor * AOE_PARTITIONS;
 229         gd->fops = &aoe_bdops;
 230         gd->private_data = d;
 231         gd->capacity = d->ssize;
 232         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%ld",
 233                 d->aoemajor, d->aoeminor);
 234
 235         gd->queue = &d->blkq;
 236         d->gd = gd;
 237         d->flags &= ~DEVFL_GDALLOC;
 238         d->flags |= DEVFL_UP;
 239
 240         spin_unlock_irqrestore(&d->lock, flags);
 241
 242         add_disk(gd);
 243         aoedisk_add_sysfs(d);
 244         return;
 245
 246 err_mempool:
 247         mempool_destroy(d->bufpool);
 248 err_disk:
 249         put_disk(gd);
 250 err:
 251         spin_lock_irqsave(&d->lock, flags);
 252         d->flags &= ~DEVFL_GDALLOC;
 253         spin_unlock_irqrestore(&d->lock, flags);
 254 }
 255
 256 void
 257 aoeblk_exit(void)
 258 {
 259         kmem_cache_destroy(buf_pool_cache);
 260 }
 261
 262 int __init
 263 aoeblk_init(void)
 264 {
 265         buf_pool_cache = kmem_cache_create("aoe_bufs",
 266                                            sizeof(struct buf),
 267                                            0, 0, NULL);
 268         if (buf_pool_cache == NULL)
 269                 return -ENOMEM;
 270
 271         return 0;
 272 }
 273