xref: /openbmc/linux/drivers/block/aoe/aoedev.c (revision 87c2ce3b)
1 /* Copyright (c) 2004 Coraid, Inc.  See COPYING for GPL terms. */
2 /*
3  * aoedev.c
4  * AoE device utility functions; maintains device list.
5  */
6 
7 #include <linux/hdreg.h>
8 #include <linux/blkdev.h>
9 #include <linux/netdevice.h>
10 #include "aoe.h"
11 
12 static struct aoedev *devlist;
13 static spinlock_t devlist_lock;
14 
15 struct aoedev *
16 aoedev_by_aoeaddr(int maj, int min)
17 {
18 	struct aoedev *d;
19 	ulong flags;
20 
21 	spin_lock_irqsave(&devlist_lock, flags);
22 
23 	for (d=devlist; d; d=d->next)
24 		if (d->aoemajor == maj && d->aoeminor == min)
25 			break;
26 
27 	spin_unlock_irqrestore(&devlist_lock, flags);
28 	return d;
29 }
30 
31 /* called with devlist lock held */
32 static struct aoedev *
33 aoedev_newdev(ulong nframes)
34 {
35 	struct aoedev *d;
36 	struct frame *f, *e;
37 
38 	d = kzalloc(sizeof *d, GFP_ATOMIC);
39 	if (d == NULL)
40 		return NULL;
41 	f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
42 	if (f == NULL) {
43 		kfree(d);
44 		return NULL;
45 	}
46 
47 	d->nframes = nframes;
48 	d->frames = f;
49 	e = f + nframes;
50 	for (; f<e; f++)
51 		f->tag = FREETAG;
52 
53 	spin_lock_init(&d->lock);
54 	init_timer(&d->timer);
55 	d->bufpool = NULL;	/* defer to aoeblk_gdalloc */
56 	INIT_LIST_HEAD(&d->bufq);
57 	d->next = devlist;
58 	devlist = d;
59 
60 	return d;
61 }
62 
63 void
64 aoedev_downdev(struct aoedev *d)
65 {
66 	struct frame *f, *e;
67 	struct buf *buf;
68 	struct bio *bio;
69 
70 	d->flags |= DEVFL_TKILL;
71 	del_timer(&d->timer);
72 
73 	f = d->frames;
74 	e = f + d->nframes;
75 	for (; f<e; f->tag = FREETAG, f->buf = NULL, f++) {
76 		if (f->tag == FREETAG || f->buf == NULL)
77 			continue;
78 		buf = f->buf;
79 		bio = buf->bio;
80 		if (--buf->nframesout == 0) {
81 			mempool_free(buf, d->bufpool);
82 			bio_endio(bio, bio->bi_size, -EIO);
83 		}
84 	}
85 	d->inprocess = NULL;
86 
87 	while (!list_empty(&d->bufq)) {
88 		buf = container_of(d->bufq.next, struct buf, bufs);
89 		list_del(d->bufq.next);
90 		bio = buf->bio;
91 		mempool_free(buf, d->bufpool);
92 		bio_endio(bio, bio->bi_size, -EIO);
93 	}
94 
95 	if (d->nopen)
96 		d->flags |= DEVFL_CLOSEWAIT;
97 	if (d->gd)
98 		d->gd->capacity = 0;
99 
100 	d->flags &= ~DEVFL_UP;
101 }
102 
103 struct aoedev *
104 aoedev_set(ulong sysminor, unsigned char *addr, struct net_device *ifp, ulong bufcnt)
105 {
106 	struct aoedev *d;
107 	ulong flags;
108 
109 	spin_lock_irqsave(&devlist_lock, flags);
110 
111 	for (d=devlist; d; d=d->next)
112 		if (d->sysminor == sysminor)
113 			break;
114 
115 	if (d == NULL && (d = aoedev_newdev(bufcnt)) == NULL) {
116 		spin_unlock_irqrestore(&devlist_lock, flags);
117 		printk(KERN_INFO "aoe: aoedev_set: aoedev_newdev failure.\n");
118 		return NULL;
119 	} /* if newdev, (d->flags & DEVFL_UP) == 0 for below */
120 
121 	spin_unlock_irqrestore(&devlist_lock, flags);
122 	spin_lock_irqsave(&d->lock, flags);
123 
124 	d->ifp = ifp;
125 	memcpy(d->addr, addr, sizeof d->addr);
126 	if ((d->flags & DEVFL_UP) == 0) {
127 		aoedev_downdev(d); /* flushes outstanding frames */
128 		d->sysminor = sysminor;
129 		d->aoemajor = AOEMAJOR(sysminor);
130 		d->aoeminor = AOEMINOR(sysminor);
131 	}
132 
133 	spin_unlock_irqrestore(&d->lock, flags);
134 	return d;
135 }
136 
137 static void
138 aoedev_freedev(struct aoedev *d)
139 {
140 	if (d->gd) {
141 		aoedisk_rm_sysfs(d);
142 		del_gendisk(d->gd);
143 		put_disk(d->gd);
144 	}
145 	kfree(d->frames);
146 	if (d->bufpool)
147 		mempool_destroy(d->bufpool);
148 	kfree(d);
149 }
150 
151 void
152 aoedev_exit(void)
153 {
154 	struct aoedev *d;
155 	ulong flags;
156 
157 	flush_scheduled_work();
158 
159 	while ((d = devlist)) {
160 		devlist = d->next;
161 
162 		spin_lock_irqsave(&d->lock, flags);
163 		aoedev_downdev(d);
164 		spin_unlock_irqrestore(&d->lock, flags);
165 
166 		del_timer_sync(&d->timer);
167 		aoedev_freedev(d);
168 	}
169 }
170 
171 int __init
172 aoedev_init(void)
173 {
174 	spin_lock_init(&devlist_lock);
175 	return 0;
176 }
177 
178