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/fs.h>
  10 #include <linux/ioctl.h>
  11 #include <linux/genhd.h>
  12 #include <linux/netdevice.h>
  13 #include "aoe.h"
  14
  15 static kmem_cache_t *buf_pool_cache;
  16
  17 static ssize_t aoedisk_show_state(struct gendisk * disk, char *page)
  18 {
  19         struct aoedev *d = disk->private_data;
  20
  21         return snprintf(page, PAGE_SIZE,
  22                         "%s%s\n",
  23                         (d->flags & DEVFL_UP) ? "up" : "down",
  24                         (d->flags & DEVFL_PAUSE) ? ",paused" :
  25                         (d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
  26         /* I'd rather see nopen exported so we can ditch closewait */
  27 }
  28 static ssize_t aoedisk_show_mac(struct gendisk * disk, char *page)
  29 {
  30         struct aoedev *d = disk->private_data;
  31
  32         return snprintf(page, PAGE_SIZE, "%012llx\n",
  33                         (unsigned long long)mac_addr(d->addr));
  34 }
  35 static ssize_t aoedisk_show_netif(struct gendisk * disk, char *page)
  36 {
  37         struct aoedev *d = disk->private_data;
  38
  39         return snprintf(page, PAGE_SIZE, "%s\n", d->ifp->name);
  40 }
  41 /* firmware version */
  42 static ssize_t aoedisk_show_fwver(struct gendisk * disk, char *page)
  43 {
  44         struct aoedev *d = disk->private_data;
  45
  46         return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
  47 }
  48
  49 static struct disk_attribute disk_attr_state = {
  50         .attr = {.name = "state", .mode = S_IRUGO },
  51         .show = aoedisk_show_state
  52 };
  53 static struct disk_attribute disk_attr_mac = {
  54         .attr = {.name = "mac", .mode = S_IRUGO },
  55         .show = aoedisk_show_mac
  56 };
  57 static struct disk_attribute disk_attr_netif = {
  58         .attr = {.name = "netif", .mode = S_IRUGO },
  59         .show = aoedisk_show_netif
  60 };
  61 static struct disk_attribute disk_attr_fwver = {
  62         .attr = {.name = "firmware-version", .mode = S_IRUGO },
  63         .show = aoedisk_show_fwver
  64 };
  65
  66 static struct attribute *aoe_attrs[] = {
  67         &disk_attr_state.attr,
  68         &disk_attr_mac.attr,
  69         &disk_attr_netif.attr,
  70         &disk_attr_fwver.attr,
  71 };
  72
  73 static const struct attribute_group attr_group = {
  74         .attrs = aoe_attrs,
  75 };
  76
  77 static int
  78 aoedisk_add_sysfs(struct aoedev *d)
  79 {
  80         return sysfs_create_group(&d->gd->kobj, &attr_group);
  81 }
  82 void
  83 aoedisk_rm_sysfs(struct aoedev *d)
  84 {
  85         sysfs_remove_group(&d->gd->kobj, &attr_group);
  86 }
  87
  88 static int
  89 aoeblk_open(struct inode *inode, struct file *filp)
  90 {
  91         struct aoedev *d;
  92         ulong flags;
  93
  94         d = inode->i_bdev->bd_disk->private_data;
  95
  96         spin_lock_irqsave(&d->lock, flags);
  97         if (d->flags & DEVFL_UP) {
  98                 d->nopen++;
  99                 spin_unlock_irqrestore(&d->lock, flags);
 100                 return 0;
 101         }
 102         spin_unlock_irqrestore(&d->lock, flags);
 103         return -ENODEV;
 104 }
 105
 106 static int
 107 aoeblk_release(struct inode *inode, struct file *filp)
 108 {
 109         struct aoedev *d;
 110         ulong flags;
 111
 112         d = inode->i_bdev->bd_disk->private_data;
 113
 114         spin_lock_irqsave(&d->lock, flags);
 115
 116         if (--d->nopen == 0) {
 117                 spin_unlock_irqrestore(&d->lock, flags);
 118                 aoecmd_cfg(d->aoemajor, d->aoeminor);
 119                 return 0;
 120         }
 121         spin_unlock_irqrestore(&d->lock, flags);
 122
 123         return 0;
 124 }
 125
 126 static int
 127 aoeblk_make_request(request_queue_t *q, struct bio *bio)
 128 {
 129         struct aoedev *d;
 130         struct buf *buf;
 131         struct sk_buff *sl;
 132         ulong flags;
 133
 134         blk_queue_bounce(q, &bio);
 135
 136         d = bio->bi_bdev->bd_disk->private_data;
 137         buf = mempool_alloc(d->bufpool, GFP_NOIO);
 138         if (buf == NULL) {
 139                 printk(KERN_INFO "aoe: buf allocation failure\n");
 140                 bio_endio(bio, bio->bi_size, -ENOMEM);
 141                 return 0;
 142         }
 143         memset(buf, 0, sizeof(*buf));
 144         INIT_LIST_HEAD(&buf->bufs);
 145         buf->start_time = jiffies;
 146         buf->bio = bio;
 147         buf->resid = bio->bi_size;
 148         buf->sector = bio->bi_sector;
 149         buf->bv = &bio->bi_io_vec[bio->bi_idx];
 150         WARN_ON(buf->bv->bv_len == 0);
 151         buf->bv_resid = buf->bv->bv_len;
 152         buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
 153
 154         spin_lock_irqsave(&d->lock, flags);
 155
 156         if ((d->flags & DEVFL_UP) == 0) {
 157                 printk(KERN_INFO "aoe: device %ld.%ld is not up\n",
 158                         d->aoemajor, d->aoeminor);
 159                 spin_unlock_irqrestore(&d->lock, flags);
 160                 mempool_free(buf, d->bufpool);
 161                 bio_endio(bio, bio->bi_size, -ENXIO);
 162                 return 0;
 163         }
 164
 165         list_add_tail(&buf->bufs, &d->bufq);
 166
 167         aoecmd_work(d);
 168         sl = d->sendq_hd;
 169         d->sendq_hd = d->sendq_tl = NULL;
 170
 171         spin_unlock_irqrestore(&d->lock, flags);
 172         aoenet_xmit(sl);
 173
 174         return 0;
 175 }
 176
 177 static int
 178 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 179 {
 180         struct aoedev *d = bdev->bd_disk->private_data;
 181
 182         if ((d->flags & DEVFL_UP) == 0) {
 183                 printk(KERN_ERR "aoe: disk not up\n");
 184                 return -ENODEV;
 185         }
 186
 187         geo->cylinders = d->geo.cylinders;
 188         geo->heads = d->geo.heads;
 189         geo->sectors = d->geo.sectors;
 190         return 0;
 191 }
 192
 193 static struct block_device_operations aoe_bdops = {
 194         .open = aoeblk_open,
 195         .release = aoeblk_release,
 196         .getgeo = aoeblk_getgeo,
 197         .owner = THIS_MODULE,
 198 };
 199
 200 /* alloc_disk and add_disk can sleep */
 201 void
 202 aoeblk_gdalloc(void *vp)
 203 {
 204         struct aoedev *d = vp;
 205         struct gendisk *gd;
 206         ulong flags;
 207
 208         gd = alloc_disk(AOE_PARTITIONS);
 209         if (gd == NULL) {
 210                 printk(KERN_ERR "aoe: cannot allocate disk structure for %ld.%ld\n",
 211                         d->aoemajor, d->aoeminor);
 212                 spin_lock_irqsave(&d->lock, flags);
 213                 d->flags &= ~DEVFL_GDALLOC;
 214                 spin_unlock_irqrestore(&d->lock, flags);
 215                 return;
 216         }
 217
 218         d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache);
 219         if (d->bufpool == NULL) {
 220                 printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%ld\n",
 221                         d->aoemajor, d->aoeminor);
 222                 put_disk(gd);
 223                 spin_lock_irqsave(&d->lock, flags);
 224                 d->flags &= ~DEVFL_GDALLOC;
 225                 spin_unlock_irqrestore(&d->lock, flags);
 226                 return;
 227         }
 228
 229         spin_lock_irqsave(&d->lock, flags);
 230         blk_queue_make_request(&d->blkq, aoeblk_make_request);
 231         gd->major = AOE_MAJOR;
 232         gd->first_minor = d->sysminor * AOE_PARTITIONS;
 233         gd->fops = &aoe_bdops;
 234         gd->private_data = d;
 235         gd->capacity = d->ssize;
 236         snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%ld",
 237                 d->aoemajor, d->aoeminor);
 238
 239         gd->queue = &d->blkq;
 240         d->gd = gd;
 241         d->flags &= ~DEVFL_GDALLOC;
 242         d->flags |= DEVFL_UP;
 243
 244         spin_unlock_irqrestore(&d->lock, flags);
 245
 246         add_disk(gd);
 247         aoedisk_add_sysfs(d);
 248 }
 249
 250 void
 251 aoeblk_exit(void)
 252 {
 253         kmem_cache_destroy(buf_pool_cache);
 254 }
 255
 256 int __init
 257 aoeblk_init(void)
 258 {
 259         buf_pool_cache = kmem_cache_create("aoe_bufs",
 260                                            sizeof(struct buf),
 261                                            0, 0, NULL, NULL);
 262         if (buf_pool_cache == NULL)
 263                 return -ENOMEM;
 264
 265         return 0;
 266 }
 267