summaryrefslogtreecommitdiff
path: root/fs/nfs/blocklayout/blocklayoutdev.c
blob: 64da33a40eaf04a782c6ba6785c26ca40ae68481 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
/*
 *  linux/fs/nfs/blocklayout/blocklayoutdev.c
 *
 *  Device operations for the pnfs nfs4 file layout driver.
 *
 *  Copyright (c) 2006 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Andy Adamson <andros@citi.umich.edu>
 *  Fred Isaman <iisaman@umich.edu>
 *
 * permission is granted to use, copy, create derivative works and
 * redistribute this software and such derivative works for any purpose,
 * so long as the name of the university of michigan is not used in
 * any advertising or publicity pertaining to the use or distribution
 * of this software without specific, written prior authorization.  if
 * the above copyright notice or any other identification of the
 * university of michigan is included in any copy of any portion of
 * this software, then the disclaimer below must also be included.
 *
 * this software is provided as is, without representation from the
 * university of michigan as to its fitness for any purpose, and without
 * warranty by the university of michigan of any kind, either express
 * or implied, including without limitation the implied warranties of
 * merchantability and fitness for a particular purpose.  the regents
 * of the university of michigan shall not be liable for any damages,
 * including special, indirect, incidental, or consequential damages,
 * with respect to any claim arising out or in connection with the use
 * of the software, even if it has been or is hereafter advised of the
 * possibility of such damages.
 */
#include <linux/module.h>
#include <linux/buffer_head.h> /* __bread */

#include <linux/genhd.h>
#include <linux/blkdev.h>
#include <linux/hash.h>

#include "blocklayout.h"

#define NFSDBG_FACILITY         NFSDBG_PNFS_LD

/* Open a block_device by device number. */
struct block_device *nfs4_blkdev_get(dev_t dev)
{
	struct block_device *bd;

	dprintk("%s enter\n", __func__);
	bd = blkdev_get_by_dev(dev, FMODE_READ, NULL);
	if (IS_ERR(bd))
		goto fail;
	return bd;
fail:
	dprintk("%s failed to open device : %ld\n",
			__func__, PTR_ERR(bd));
	return NULL;
}

/*
 * Release the block device
 */
int nfs4_blkdev_put(struct block_device *bdev)
{
	dprintk("%s for device %d:%d\n", __func__, MAJOR(bdev->bd_dev),
			MINOR(bdev->bd_dev));
	return blkdev_put(bdev, FMODE_READ);
}

/*
 * Shouldn't there be a rpc_generic_upcall() to do this for us?
 */
ssize_t bl_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg,
		       char __user *dst, size_t buflen)
{
	char *data = (char *)msg->data + msg->copied;
	size_t mlen = min(msg->len - msg->copied, buflen);
	unsigned long left;

	left = copy_to_user(dst, data, mlen);
	if (left == mlen) {
		msg->errno = -EFAULT;
		return -EFAULT;
	}

	mlen -= left;
	msg->copied += mlen;
	msg->errno = 0;
	return mlen;
}

static struct bl_dev_msg bl_mount_reply;

ssize_t bl_pipe_downcall(struct file *filp, const char __user *src,
			 size_t mlen)
{
	if (mlen != sizeof (struct bl_dev_msg))
		return -EINVAL;

	if (copy_from_user(&bl_mount_reply, src, mlen) != 0)
		return -EFAULT;

	wake_up(&bl_wq);

	return mlen;
}

void bl_pipe_destroy_msg(struct rpc_pipe_msg *msg)
{
	if (msg->errno >= 0)
		return;
	wake_up(&bl_wq);
}

/*
 * Decodes pnfs_block_deviceaddr4 which is XDR encoded in dev->dev_addr_buf.
 */
struct pnfs_block_dev *
nfs4_blk_decode_device(struct nfs_server *server,
		       struct pnfs_device *dev,
		       struct list_head *sdlist)
{
	struct pnfs_block_dev *rv = NULL;
	struct block_device *bd = NULL;
	struct rpc_pipe_msg msg;
	struct bl_msg_hdr bl_msg = {
		.type = BL_DEVICE_MOUNT,
		.totallen = dev->mincount,
	};
	uint8_t *dataptr;
	DECLARE_WAITQUEUE(wq, current);
	struct bl_dev_msg *reply = &bl_mount_reply;

	dprintk("%s CREATING PIPEFS MESSAGE\n", __func__);
	dprintk("%s: deviceid: %s, mincount: %d\n", __func__, dev->dev_id.data,
		dev->mincount);

	memset(&msg, 0, sizeof(msg));
	msg.data = kzalloc(sizeof(bl_msg) + dev->mincount, GFP_NOFS);
	if (!msg.data) {
		rv = ERR_PTR(-ENOMEM);
		goto out;
	}

	memcpy(msg.data, &bl_msg, sizeof(bl_msg));
	dataptr = (uint8_t *) msg.data;
	memcpy(&dataptr[sizeof(bl_msg)], dev->area, dev->mincount);
	msg.len = sizeof(bl_msg) + dev->mincount;

	dprintk("%s CALLING USERSPACE DAEMON\n", __func__);
	add_wait_queue(&bl_wq, &wq);
	if (rpc_queue_upcall(bl_device_pipe->d_inode, &msg) < 0) {
		remove_wait_queue(&bl_wq, &wq);
		goto out;
	}

	set_current_state(TASK_UNINTERRUPTIBLE);
	schedule();
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&bl_wq, &wq);

	if (reply->status != BL_DEVICE_REQUEST_PROC) {
		dprintk("%s failed to open device: %d\n",
			__func__, reply->status);
		rv = ERR_PTR(-EINVAL);
		goto out;
	}

	bd = nfs4_blkdev_get(MKDEV(reply->major, reply->minor));
	if (IS_ERR(bd)) {
		dprintk("%s failed to open device : %ld\n",
			__func__, PTR_ERR(bd));
		goto out;
	}

	rv = kzalloc(sizeof(*rv), GFP_NOFS);
	if (!rv) {
		rv = ERR_PTR(-ENOMEM);
		goto out;
	}

	rv->bm_mdev = bd;
	memcpy(&rv->bm_mdevid, &dev->dev_id, sizeof(struct nfs4_deviceid));
	dprintk("%s Created device %s with bd_block_size %u\n",
		__func__,
		bd->bd_disk->disk_name,
		bd->bd_block_size);

out:
	kfree(msg.data);
	return rv;
}

int
nfs4_blk_process_layoutget(struct pnfs_layout_hdr *lo,
			   struct nfs4_layoutget_res *lgr, gfp_t gfp_flags)
{
	/* STUB */
	return -EIO;
}