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
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
|
/*
* Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
/**
* @file
*
* Block device translator
*
*/
#include <stdlib.h>
#include <errno.h>
#include <assert.h>
#include <ipxe/iobuf.h>
#include <ipxe/xfer.h>
#include <ipxe/blockdev.h>
#include <ipxe/blocktrans.h>
/**
* Reallocate block device translator data buffer
*
* @v xferbuf Data transfer buffer
* @v len New length (or zero to free buffer)
* @ret rc Return status code
*/
static int blktrans_xferbuf_realloc ( struct xfer_buffer *xferbuf,
size_t len ) {
struct block_translator *blktrans =
container_of ( xferbuf, struct block_translator, xferbuf );
/* Record length, if applicable */
if ( blktrans->buffer ) {
/* We have a (non-reallocatable) data buffer */
return -ENOTSUP;
} else {
/* Record length (for block device capacity) */
xferbuf->len = len;
return 0;
}
}
/**
* Write data to block device translator data buffer
*
* @v xferbuf Data transfer buffer
* @v offset Starting offset
* @v data Data to copy
* @v len Length of data
*/
static void blktrans_xferbuf_write ( struct xfer_buffer *xferbuf, size_t offset,
const void *data, size_t len ) {
struct block_translator *blktrans =
container_of ( xferbuf, struct block_translator, xferbuf );
/* Write data to buffer, if applicable */
if ( blktrans->buffer ) {
/* Write data to buffer */
copy_to_user ( blktrans->buffer, offset, data, len );
} else {
/* Sanity check */
assert ( len == 0 );
}
}
/**
* Read data from block device translator data buffer
*
* @v xferbuf Data transfer buffer
* @v offset Starting offset
* @v data Data to read
* @v len Length of data
*/
static void blktrans_xferbuf_read ( struct xfer_buffer *xferbuf, size_t offset,
void *data, size_t len ) {
struct block_translator *blktrans =
container_of ( xferbuf, struct block_translator, xferbuf );
/* Read data from buffer, if applicable */
if ( blktrans->buffer ) {
/* Read data from buffer */
copy_from_user ( data, blktrans->buffer, offset, len );
} else {
/* Sanity check */
assert ( len == 0 );
}
}
/** Block device translator data transfer buffer operations */
static struct xfer_buffer_operations blktrans_xferbuf_operations = {
.realloc = blktrans_xferbuf_realloc,
.write = blktrans_xferbuf_write,
.read = blktrans_xferbuf_read,
};
/**
* Close block device translator
*
* @v blktrans Block device translator
* @v rc Reason for close
*/
static void blktrans_close ( struct block_translator *blktrans, int rc ) {
struct block_device_capacity capacity;
/* Report block device capacity, if applicable */
if ( ( rc == 0 ) && ( blktrans->blksize ) ) {
/* Construct block device capacity */
capacity.blocks =
( blktrans->xferbuf.len / blktrans->blksize );
capacity.blksize = blktrans->blksize;
capacity.max_count = -1U;
/* Report block device capacity */
block_capacity ( &blktrans->block, &capacity );
}
/* Shut down interfaces */
intf_shutdown ( &blktrans->xfer, rc );
intf_shutdown ( &blktrans->block, rc );
}
/**
* Deliver data
*
* @v blktrans Block device translator
* @v iobuf I/O buffer
* @v meta Data transfer metadata
* @ret rc Return status code
*/
static int blktrans_deliver ( struct block_translator *blktrans,
struct io_buffer *iobuf,
struct xfer_metadata *meta ) {
int rc;
/* Deliver to buffer */
if ( ( rc = xferbuf_deliver ( &blktrans->xferbuf, iob_disown ( iobuf ),
meta ) ) != 0 ) {
DBGC ( blktrans, "BLKTRANS %p could not deliver: %s\n",
blktrans, strerror ( rc ) );
goto err;
}
return 0;
err:
blktrans_close ( blktrans, rc );
return rc;
}
/**
* Get underlying data transfer buffer
*
* @v blktrans Block device translator
* @ret xferbuf Data transfer buffer
*/
static struct xfer_buffer *
blktrans_buffer ( struct block_translator *blktrans ) {
return &blktrans->xferbuf;
}
/** Block device translator block device interface operations */
static struct interface_operation blktrans_block_operations[] = {
INTF_OP ( intf_close, struct block_translator *, blktrans_close ),
};
/** Block device translator block device interface descriptor */
static struct interface_descriptor blktrans_block_desc =
INTF_DESC_PASSTHRU ( struct block_translator, block,
blktrans_block_operations, xfer );
/** Block device translator data transfer interface operations */
static struct interface_operation blktrans_xfer_operations[] = {
INTF_OP ( xfer_deliver, struct block_translator *, blktrans_deliver ),
INTF_OP ( xfer_buffer, struct block_translator *, blktrans_buffer ),
INTF_OP ( intf_close, struct block_translator *, blktrans_close ),
};
/** Block device translator data transfer interface descriptor */
static struct interface_descriptor blktrans_xfer_desc =
INTF_DESC_PASSTHRU ( struct block_translator, xfer,
blktrans_xfer_operations, block );
/**
* Insert block device translator
*
* @v block Block device interface
* @v buffer Data buffer (or UNULL)
* @v size Length of data buffer, or block size
* @ret rc Return status code
*/
int block_translate ( struct interface *block, userptr_t buffer, size_t size ) {
struct block_translator *blktrans;
int rc;
/* Allocate and initialise structure */
blktrans = zalloc ( sizeof ( *blktrans ) );
if ( ! blktrans ) {
rc = -ENOMEM;
goto err_alloc;
}
ref_init ( &blktrans->refcnt, NULL );
intf_init ( &blktrans->block, &blktrans_block_desc, &blktrans->refcnt );
intf_init ( &blktrans->xfer, &blktrans_xfer_desc, &blktrans->refcnt );
blktrans->xferbuf.op = &blktrans_xferbuf_operations;
blktrans->buffer = buffer;
if ( buffer ) {
blktrans->xferbuf.len = size;
} else {
blktrans->blksize = size;
}
/* Attach to interfaces, mortalise self, and return */
assert ( block->dest != &null_intf );
intf_plug_plug ( &blktrans->xfer, block->dest );
intf_plug_plug ( &blktrans->block, block );
ref_put ( &blktrans->refcnt );
DBGC2 ( blktrans, "BLKTRANS %p created", blktrans );
if ( buffer ) {
DBGC2 ( blktrans, " for %#lx+%#zx",
user_to_phys ( buffer, 0 ), size );
}
DBGC2 ( blktrans, "\n" );
return 0;
ref_put ( &blktrans->refcnt );
err_alloc:
return rc;
}
|
