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 gendisk * disk, char *page)
  19 {
  20         struct aoedev *d = disk->private_data;
  21
  22         return snprintf(page, PAGE_SIZE,
  23                         "%s%s\n",
  24                         (d->flags & DEVFL_UP) ? "up" : "down",
  25                         (d->flags & DEVFL_PAUSE) ? ",paused" :
  26                         (d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
  27         /* I'd rather see nopen exported so we can ditch closewait */
  28 }
  29 static ssize_t aoedisk_show_mac(struct gendisk * disk, char *page)
  30 {
  31         struct aoedev *d = disk->private_data;
  32
  33         return snprintf(page, PAGE_SIZE, "%012llx\n",
  34                         (unsigned long long)mac_addr(d->addr));
  35 }
  36 static ssize_t aoedisk_show_netif(struct gendisk * disk, char *page)
  37 {
  38         struct aoedev *d = disk->private_data;
  39
  40         return snprintf(page, PAGE_SIZE, "%s\n", d->ifp->name);
  41 }
  42 /* firmware version */
  43 static ssize_t aoedisk_show_fwver(struct gendisk * disk, char *page)
  44 {
  45         struct aoedev *d = disk->private_data;
  46
  47         return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
  48 }
  49
  50 static struct disk_attribute disk_attr_state = {
  51         .attr = {.name = "state", .mode = S_IRUGO },
  52         .show = aoedisk_show_state
  53 };
  54 static struct disk_attribute disk_attr_mac = {
  55         .attr = {.name = "mac", .mode = S_IRUGO },
  56         .show = aoedisk_show_mac
  57 };
  58 static struct disk_attribute disk_attr_netif = {
  59         .attr = {.name = "netif", .mode = S_IRUGO },
  60         .show = aoedisk_show_netif
  61 };
  62 static struct disk_attribute disk_attr_fwver = {
  63         .attr = {.name = "firmware-version", .mode = S_IRUGO },
  64         .show = aoedisk_show_fwver
  65 };
  66
  67 static struct attribute *aoe_attrs[] = {
  68         &disk_attr_state.attr,
  69         &disk_attr_mac.attr,
  70         &disk_attr_netif.attr,
  71         &disk_attr_fwver.attr,
  72         NULL
  73 };
  74
  75 static const struct attribute_group attr_group = {
  76         .attrs = aoe_attrs,
  77 };
  78
  79 static int
  80 aoedisk_add_sysfs(struct aoedev *d)
  81 {
  82         return sysfs_create_group(&d->gd->kobj, &attr_group);
  83 }
  84 void
  85 aoedisk_rm_sysfs(struct aoedev *d)
  86 {
  87         sysfs_remove_group(&d->gd->kobj, &attr_group);
  88 }
  89
  90 static int
  91 aoeblk_open(struct inode *inode, struct file *filp)
  92 {
  93         struct aoedev *d;
  94         ulong flags;
  95
  96         d = inode->i_bdev->bd_disk->private_data;
  97
  98         spin_lock_irqsave(&d->lock, flags);
  99         if (d->flags & DEVFL_UP) {
 100                 d->nopen++;
 101                 spin_unlock_irqrestore(&d->lock, flags);
 102                 return 0;
 103         }
 104         spin_unlock_irqrestore(&d->lock, flags);
 105         return -ENODEV;
 106 }
 107
 108 static int
 109 aoeblk_release(struct inode *inode, struct file *filp)
 110 {
 111         struct aoedev *d;
 112         ulong flags;
 113
 114         d = inode->i_bdev->bd_disk->private_data;
 115
 116         spin_lock_irqsave(&d->lock, flags);
 117
 118         if (--d->nopen == 0) {
 119                 spin_unlock_irqrestore(&d->lock, flags);
 120                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 121                 return 0;
 122         }
 123         spin_unlock_irqrestore(&d->lock, flags);
 124
 125         return 0;
 126 }
 127
 128 static int
 129 aoeblk_make_request(struct request_queue *q, struct bio *bio)
 130 {
 131         struct aoedev *d;
 132         struct buf *buf;
 133         struct sk_buff *sl;
 134         ulong flags;
 135
 136         blk_queue_bounce(q, &bio);
 137
 138         d = bio->bi_bdev->bd_disk->private_data;
 139         buf = mempool_alloc(d->bufpool, GFP_NOIO);
 140         if (buf == NULL) {
 141                 printk(KERN_INFO "aoe: buf allocation failure\n");
 142                 bio_endio(bio, -ENOMEM);
 143                 return 0;
 144         }
 145         memset(buf, 0, sizeof(*buf));
 146         INIT_LIST_HEAD(&buf->bufs);
 147         buf->start_time = jiffies;
 148         buf->bio = bio;
 149         buf->resid = bio->bi_size;
 150         buf->sector = bio->bi_sector;
 151         buf->bv = &bio->bi_io_vec[bio->bi_idx];
 152         WARN_ON(buf->bv->bv_len == 0);
 153         buf->bv_resid = buf->bv->bv_len;
 154         buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
 155
 156         spin_lock_irqsave(&d->lock, flags);
 157
 158         if ((d->flags & DEVFL_UP) == 0) {
 159                 printk(KERN_INFO "aoe: device %ld.%ld is not up\n",
 160                         d->aoemajor, d->aoeminor);
 161                 spin_unlock_irqrestore(&d->lock, flags);
 162                 mempool_free(buf, d->bufpool);
 163                 bio_endio(bio, -ENXIO);
 164                 return 0;
 165         }
 166
 167         list_add_tail(&buf->bufs, &d->bufq);
 168
 169         aoecmd_work(d);
 170         sl = d->sendq_hd;
 171         d->sendq_hd = d->sendq_tl = NULL;
 172
 173         spin_unlock_irqrestore(&d->lock, flags);
 174         aoenet_xmit(sl);
 175
 176         return 0;
 177 }
 178
 179 static int
 180 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 181 {
 182         struct aoedev *d = bdev->bd_disk->private_data;
 183
 184         if ((d->flags & DEVFL_UP) == 0) {
 185                 printk(KERN_ERR "aoe: disk not up\n");
 186                 return -ENODEV;
 187         }
 188
 189         geo->cylinders = d->geo.cylinders;
 190         geo->heads = d->geo.heads;
 191         geo->sectors = d->geo.sectors;
 192         return 0;
 193 }
 194
 195 static struct block_device_operations aoe_bdops = {
 196         .open = aoeblk_open,
 197         .release = aoeblk_release,
 198         .getgeo = aoeblk_getgeo,
 199         .owner = THIS_MODULE,
 200 };
 201
 202 /* alloc_disk and add_disk can sleep */
 203 void
 204 aoeblk_gdalloc(void *vp)
 205 {
 206         struct aoedev *d = vp;
 207         struct gendisk *gd;
 208         ulong flags;
 209
 210         gd = alloc_disk(AOE_PARTITIONS);
 211         if (gd == NULL) {
 212                 printk(KERN_ERR "aoe: cannot allocate disk structure for %ld.%ld\n",
 213                         d->aoemajor, d->aoeminor);
 214                 goto err;
 215         }
 216
 217         d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache);
 218         if (d->bufpool == NULL) {
 219                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%ld\n",
 220                         d->aoemajor, d->aoeminor);
 221                 goto err_disk;
 222         }
 223
 224         blk_queue_make_request(&d->blkq, aoeblk_make_request);
 225         if (bdi_init(&d->blkq.backing_dev_info))
 226                 goto err_mempool;
 227         spin_lock_irqsave(&d->lock, flags);
 228         gd->major = AOE_MAJOR;
 229         gd->first_minor = d->sysminor * AOE_PARTITIONS;
 230         gd->fops = &aoe_bdops;
 231         gd->private_data = d;
 232         gd->capacity = d->ssize;
 233         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%ld",
 234                 d->aoemajor, d->aoeminor);
 235
 236         gd->queue = &d->blkq;
 237         d->gd = gd;
 238         d->flags &= ~DEVFL_GDALLOC;
 239         d->flags |= DEVFL_UP;
 240
 241         spin_unlock_irqrestore(&d->lock, flags);
 242
 243         add_disk(gd);
 244         aoedisk_add_sysfs(d);
 245         return;
 246
 247 err_mempool:
 248         mempool_destroy(d->bufpool);
 249 err_disk:
 250         put_disk(gd);
 251 err:
 252         spin_lock_irqsave(&d->lock, flags);
 253         d->flags &= ~DEVFL_GDALLOC;
 254         spin_unlock_irqrestore(&d->lock, flags);
 255 }
 256
 257 void
 258 aoeblk_exit(void)
 259 {
 260         kmem_cache_destroy(buf_pool_cache);
 261 }
 262
 263 int __init
 264 aoeblk_init(void)
 265 {
 266         buf_pool_cache = kmem_cache_create("aoe_bufs",
 267                                            sizeof(struct buf),
 268                                            0, 0, NULL);
 269         if (buf_pool_cache == NULL)
 270                 return -ENOMEM;
 271
 272         return 0;
 273 }
 274