[PATCH] aoe [1/8]: zero packet data after skb allocation
[linux-2.6] / drivers / block / aoe / aoeblk.c
1 /* Copyright (c) 2004 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 /* add attributes for our block devices in sysfs */
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_CLOSEWAIT) ? ",closewait" : "");
26 }
27 static ssize_t aoedisk_show_mac(struct gendisk * disk, char *page)
28 {
29         struct aoedev *d = disk->private_data;
30
31         return snprintf(page, PAGE_SIZE, "%012llx\n",
32                         (unsigned long long)mac_addr(d->addr));
33 }
34 static ssize_t aoedisk_show_netif(struct gendisk * disk, char *page)
35 {
36         struct aoedev *d = disk->private_data;
37
38         return snprintf(page, PAGE_SIZE, "%s\n", d->ifp->name);
39 }
40 /* firmware version */
41 static ssize_t aoedisk_show_fwver(struct gendisk * disk, char *page)
42 {
43         struct aoedev *d = disk->private_data;
44
45         return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
46 }
47
48 static struct disk_attribute disk_attr_state = {
49         .attr = {.name = "state", .mode = S_IRUGO },
50         .show = aoedisk_show_state
51 };
52 static struct disk_attribute disk_attr_mac = {
53         .attr = {.name = "mac", .mode = S_IRUGO },
54         .show = aoedisk_show_mac
55 };
56 static struct disk_attribute disk_attr_netif = {
57         .attr = {.name = "netif", .mode = S_IRUGO },
58         .show = aoedisk_show_netif
59 };
60 static struct disk_attribute disk_attr_fwver = {
61         .attr = {.name = "firmware-version", .mode = S_IRUGO },
62         .show = aoedisk_show_fwver
63 };
64
65 static void
66 aoedisk_add_sysfs(struct aoedev *d)
67 {
68         sysfs_create_file(&d->gd->kobj, &disk_attr_state.attr);
69         sysfs_create_file(&d->gd->kobj, &disk_attr_mac.attr);
70         sysfs_create_file(&d->gd->kobj, &disk_attr_netif.attr);
71         sysfs_create_file(&d->gd->kobj, &disk_attr_fwver.attr);
72 }
73 void
74 aoedisk_rm_sysfs(struct aoedev *d)
75 {
76         sysfs_remove_link(&d->gd->kobj, "state");
77         sysfs_remove_link(&d->gd->kobj, "mac");
78         sysfs_remove_link(&d->gd->kobj, "netif");
79         sysfs_remove_link(&d->gd->kobj, "firmware-version");
80 }
81
82 static int
83 aoeblk_open(struct inode *inode, struct file *filp)
84 {
85         struct aoedev *d;
86         ulong flags;
87
88         d = inode->i_bdev->bd_disk->private_data;
89
90         spin_lock_irqsave(&d->lock, flags);
91         if (d->flags & DEVFL_UP) {
92                 d->nopen++;
93                 spin_unlock_irqrestore(&d->lock, flags);
94                 return 0;
95         }
96         spin_unlock_irqrestore(&d->lock, flags);
97         return -ENODEV;
98 }
99
100 static int
101 aoeblk_release(struct inode *inode, struct file *filp)
102 {
103         struct aoedev *d;
104         ulong flags;
105
106         d = inode->i_bdev->bd_disk->private_data;
107
108         spin_lock_irqsave(&d->lock, flags);
109
110         if (--d->nopen == 0 && (d->flags & DEVFL_CLOSEWAIT)) {
111                 d->flags &= ~DEVFL_CLOSEWAIT;
112                 spin_unlock_irqrestore(&d->lock, flags);
113                 aoecmd_cfg(d->aoemajor, d->aoeminor);
114                 return 0;
115         }
116         spin_unlock_irqrestore(&d->lock, flags);
117
118         return 0;
119 }
120
121 static int
122 aoeblk_make_request(request_queue_t *q, struct bio *bio)
123 {
124         struct aoedev *d;
125         struct buf *buf;
126         struct sk_buff *sl;
127         ulong flags;
128
129         blk_queue_bounce(q, &bio);
130
131         d = bio->bi_bdev->bd_disk->private_data;
132         buf = mempool_alloc(d->bufpool, GFP_NOIO);
133         if (buf == NULL) {
134                 printk(KERN_INFO "aoe: aoeblk_make_request: buf allocation "
135                         "failure\n");
136                 bio_endio(bio, bio->bi_size, -ENOMEM);
137                 return 0;
138         }
139         memset(buf, 0, sizeof(*buf));
140         INIT_LIST_HEAD(&buf->bufs);
141         buf->start_time = jiffies;
142         buf->bio = bio;
143         buf->resid = bio->bi_size;
144         buf->sector = bio->bi_sector;
145         buf->bv = buf->bio->bi_io_vec;
146         buf->bv_resid = buf->bv->bv_len;
147         buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
148
149         spin_lock_irqsave(&d->lock, flags);
150
151         if ((d->flags & DEVFL_UP) == 0) {
152                 printk(KERN_INFO "aoe: aoeblk_make_request: device %ld.%ld is not up\n",
153                         d->aoemajor, d->aoeminor);
154                 spin_unlock_irqrestore(&d->lock, flags);
155                 mempool_free(buf, d->bufpool);
156                 bio_endio(bio, bio->bi_size, -ENXIO);
157                 return 0;
158         }
159
160         list_add_tail(&buf->bufs, &d->bufq);
161         aoecmd_work(d);
162
163         sl = d->sendq_hd;
164         d->sendq_hd = d->sendq_tl = NULL;
165
166         spin_unlock_irqrestore(&d->lock, flags);
167
168         aoenet_xmit(sl);
169         return 0;
170 }
171
172 static int
173 aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
174 {
175         struct aoedev *d = bdev->bd_disk->private_data;
176
177         if ((d->flags & DEVFL_UP) == 0) {
178                 printk(KERN_ERR "aoe: aoeblk_ioctl: disk not up\n");
179                 return -ENODEV;
180         }
181
182         geo->cylinders = d->geo.cylinders;
183         geo->heads = d->geo.heads;
184         geo->sectors = d->geo.sectors;
185         return 0;
186 }
187
188 static struct block_device_operations aoe_bdops = {
189         .open = aoeblk_open,
190         .release = aoeblk_release,
191         .getgeo = aoeblk_getgeo,
192         .owner = THIS_MODULE,
193 };
194
195 /* alloc_disk and add_disk can sleep */
196 void
197 aoeblk_gdalloc(void *vp)
198 {
199         struct aoedev *d = vp;
200         struct gendisk *gd;
201         ulong flags;
202
203         gd = alloc_disk(AOE_PARTITIONS);
204         if (gd == NULL) {
205                 printk(KERN_ERR "aoe: aoeblk_gdalloc: cannot allocate disk "
206                         "structure for %ld.%ld\n", d->aoemajor, d->aoeminor);
207                 spin_lock_irqsave(&d->lock, flags);
208                 d->flags &= ~DEVFL_WORKON;
209                 spin_unlock_irqrestore(&d->lock, flags);
210                 return;
211         }
212
213         d->bufpool = mempool_create(MIN_BUFS,
214                                     mempool_alloc_slab, mempool_free_slab,
215                                     buf_pool_cache);
216         if (d->bufpool == NULL) {
217                 printk(KERN_ERR "aoe: aoeblk_gdalloc: cannot allocate bufpool "
218                         "for %ld.%ld\n", d->aoemajor, d->aoeminor);
219                 put_disk(gd);
220                 spin_lock_irqsave(&d->lock, flags);
221                 d->flags &= ~DEVFL_WORKON;
222                 spin_unlock_irqrestore(&d->lock, flags);
223                 return;
224         }
225
226         spin_lock_irqsave(&d->lock, flags);
227         blk_queue_make_request(&d->blkq, aoeblk_make_request);
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_WORKON;
239         d->flags |= DEVFL_UP;
240
241         spin_unlock_irqrestore(&d->lock, flags);
242
243         add_disk(gd);
244         aoedisk_add_sysfs(d);
245         
246         printk(KERN_INFO "aoe: %012llx e%lu.%lu v%04x has %llu "
247                 "sectors\n", (unsigned long long)mac_addr(d->addr),
248                 d->aoemajor, d->aoeminor,
249                 d->fw_ver, (long long)d->ssize);
250 }
251
252 void
253 aoeblk_exit(void)
254 {
255         kmem_cache_destroy(buf_pool_cache);
256 }
257
258 int __init
259 aoeblk_init(void)
260 {
261         buf_pool_cache = kmem_cache_create("aoe_bufs", 
262                                            sizeof(struct buf),
263                                            0, 0, NULL, NULL);
264         if (buf_pool_cache == NULL)
265                 return -ENOMEM;
266
267         return 0;
268 }
269