blob: 7e1377fcfdcee6a96f7da0e5a41a4252a1ed0384 [file] [log] [blame]
Jim Reesfe0a9b72011-07-30 20:52:42 -04001/*
2 * linux/fs/nfs/blocklayout/blocklayoutdev.c
3 *
4 * Device operations for the pnfs nfs4 file layout driver.
5 *
6 * Copyright (c) 2006 The Regents of the University of Michigan.
7 * All rights reserved.
8 *
9 * Andy Adamson <andros@citi.umich.edu>
10 * Fred Isaman <iisaman@umich.edu>
11 *
12 * permission is granted to use, copy, create derivative works and
13 * redistribute this software and such derivative works for any purpose,
14 * so long as the name of the university of michigan is not used in
15 * any advertising or publicity pertaining to the use or distribution
16 * of this software without specific, written prior authorization. if
17 * the above copyright notice or any other identification of the
18 * university of michigan is included in any copy of any portion of
19 * this software, then the disclaimer below must also be included.
20 *
21 * this software is provided as is, without representation from the
22 * university of michigan as to its fitness for any purpose, and without
23 * warranty by the university of michigan of any kind, either express
24 * or implied, including without limitation the implied warranties of
25 * merchantability and fitness for a particular purpose. the regents
26 * of the university of michigan shall not be liable for any damages,
27 * including special, indirect, incidental, or consequential damages,
28 * with respect to any claim arising out or in connection with the use
29 * of the software, even if it has been or is hereafter advised of the
30 * possibility of such damages.
31 */
32#include <linux/module.h>
33#include <linux/buffer_head.h> /* __bread */
34
35#include <linux/genhd.h>
36#include <linux/blkdev.h>
37#include <linux/hash.h>
38
39#include "blocklayout.h"
40
41#define NFSDBG_FACILITY NFSDBG_PNFS_LD
42
43/* Open a block_device by device number. */
44struct block_device *nfs4_blkdev_get(dev_t dev)
45{
46 struct block_device *bd;
47
48 dprintk("%s enter\n", __func__);
49 bd = blkdev_get_by_dev(dev, FMODE_READ, NULL);
50 if (IS_ERR(bd))
51 goto fail;
52 return bd;
53fail:
54 dprintk("%s failed to open device : %ld\n",
55 __func__, PTR_ERR(bd));
56 return NULL;
57}
58
59/*
60 * Release the block device
61 */
62int nfs4_blkdev_put(struct block_device *bdev)
63{
64 dprintk("%s for device %d:%d\n", __func__, MAJOR(bdev->bd_dev),
65 MINOR(bdev->bd_dev));
66 return blkdev_put(bdev, FMODE_READ);
67}
68
69/*
70 * Shouldn't there be a rpc_generic_upcall() to do this for us?
71 */
72ssize_t bl_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg,
73 char __user *dst, size_t buflen)
74{
75 char *data = (char *)msg->data + msg->copied;
76 size_t mlen = min(msg->len - msg->copied, buflen);
77 unsigned long left;
78
79 left = copy_to_user(dst, data, mlen);
80 if (left == mlen) {
81 msg->errno = -EFAULT;
82 return -EFAULT;
83 }
84
85 mlen -= left;
86 msg->copied += mlen;
87 msg->errno = 0;
88 return mlen;
89}
90
91static struct bl_dev_msg bl_mount_reply;
92
93ssize_t bl_pipe_downcall(struct file *filp, const char __user *src,
94 size_t mlen)
95{
96 if (mlen != sizeof (struct bl_dev_msg))
97 return -EINVAL;
98
99 if (copy_from_user(&bl_mount_reply, src, mlen) != 0)
100 return -EFAULT;
101
102 wake_up(&bl_wq);
103
104 return mlen;
105}
106
107void bl_pipe_destroy_msg(struct rpc_pipe_msg *msg)
108{
109 if (msg->errno >= 0)
110 return;
111 wake_up(&bl_wq);
112}
113
114/*
115 * Decodes pnfs_block_deviceaddr4 which is XDR encoded in dev->dev_addr_buf.
116 */
117struct pnfs_block_dev *
118nfs4_blk_decode_device(struct nfs_server *server,
119 struct pnfs_device *dev,
120 struct list_head *sdlist)
121{
122 struct pnfs_block_dev *rv = NULL;
123 struct block_device *bd = NULL;
124 struct rpc_pipe_msg msg;
125 struct bl_msg_hdr bl_msg = {
126 .type = BL_DEVICE_MOUNT,
127 .totallen = dev->mincount,
128 };
129 uint8_t *dataptr;
130 DECLARE_WAITQUEUE(wq, current);
131 struct bl_dev_msg *reply = &bl_mount_reply;
132
133 dprintk("%s CREATING PIPEFS MESSAGE\n", __func__);
134 dprintk("%s: deviceid: %s, mincount: %d\n", __func__, dev->dev_id.data,
135 dev->mincount);
136
137 memset(&msg, 0, sizeof(msg));
138 msg.data = kzalloc(sizeof(bl_msg) + dev->mincount, GFP_NOFS);
139 if (!msg.data) {
140 rv = ERR_PTR(-ENOMEM);
141 goto out;
142 }
143
144 memcpy(msg.data, &bl_msg, sizeof(bl_msg));
145 dataptr = (uint8_t *) msg.data;
146 memcpy(&dataptr[sizeof(bl_msg)], dev->area, dev->mincount);
147 msg.len = sizeof(bl_msg) + dev->mincount;
148
149 dprintk("%s CALLING USERSPACE DAEMON\n", __func__);
150 add_wait_queue(&bl_wq, &wq);
151 if (rpc_queue_upcall(bl_device_pipe->d_inode, &msg) < 0) {
152 remove_wait_queue(&bl_wq, &wq);
153 goto out;
154 }
155
156 set_current_state(TASK_UNINTERRUPTIBLE);
157 schedule();
158 __set_current_state(TASK_RUNNING);
159 remove_wait_queue(&bl_wq, &wq);
160
161 if (reply->status != BL_DEVICE_REQUEST_PROC) {
162 dprintk("%s failed to open device: %d\n",
163 __func__, reply->status);
164 rv = ERR_PTR(-EINVAL);
165 goto out;
166 }
167
168 bd = nfs4_blkdev_get(MKDEV(reply->major, reply->minor));
169 if (IS_ERR(bd)) {
170 dprintk("%s failed to open device : %ld\n",
171 __func__, PTR_ERR(bd));
172 goto out;
173 }
174
175 rv = kzalloc(sizeof(*rv), GFP_NOFS);
176 if (!rv) {
177 rv = ERR_PTR(-ENOMEM);
178 goto out;
179 }
180
181 rv->bm_mdev = bd;
182 memcpy(&rv->bm_mdevid, &dev->dev_id, sizeof(struct nfs4_deviceid));
183 dprintk("%s Created device %s with bd_block_size %u\n",
184 __func__,
185 bd->bd_disk->disk_name,
186 bd->bd_block_size);
187
188out:
189 kfree(msg.data);
190 return rv;
191}