2 * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or (at your option) any later version.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19 * You can also choose to distribute this program under the terms of
20 * the Unmodified Binary Distribution Licence (as given in the file
21 * COPYING.UBDL), provided that you have satisfied its requirements.
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
29 #include <ipxe/xfer.h>
30 #include <ipxe/iobuf.h>
31 #include <ipxe/umalloc.h>
32 #include <ipxe/profile.h>
33 #include <ipxe/xferbuf.h>
37 * Data transfer buffer
41 /** Data delivery profiler */
42 static struct profiler xferbuf_deliver_profiler __profiler =
43 { .name = "xferbuf.deliver" };
45 /** Data write profiler */
46 static struct profiler xferbuf_write_profiler __profiler =
47 { .name = "xferbuf.write" };
49 /** Data read profiler */
50 static struct profiler xferbuf_read_profiler __profiler =
51 { .name = "xferbuf.read" };
54 * Free data transfer buffer
56 * @v xferbuf Data transfer buffer
58 void xferbuf_free ( struct xfer_buffer *xferbuf ) {
60 xferbuf->op->realloc ( xferbuf, 0 );
66 * Ensure that data transfer buffer is large enough for the specified size
68 * @v xferbuf Data transfer buffer
69 * @v len Required minimum size
70 * @ret rc Return status code
72 static int xferbuf_ensure_size ( struct xfer_buffer *xferbuf, size_t len ) {
75 /* If buffer is already large enough, do nothing */
76 if ( len <= xferbuf->len )
80 if ( ( rc = xferbuf->op->realloc ( xferbuf, len ) ) != 0 ) {
81 DBGC ( xferbuf, "XFERBUF %p could not extend buffer to "
82 "%zd bytes: %s\n", xferbuf, len, strerror ( rc ) );
91 * Write to data transfer buffer
93 * @v xferbuf Data transfer buffer
94 * @v offset Starting offset
95 * @v data Data to write
96 * @v len Length of data
98 int xferbuf_write ( struct xfer_buffer *xferbuf, size_t offset,
99 const void *data, size_t len ) {
103 /* Check for overflow */
104 max_len = ( offset + len );
105 if ( max_len < offset )
108 /* Ensure buffer is large enough to contain this write */
109 if ( ( rc = xferbuf_ensure_size ( xferbuf, max_len ) ) != 0 )
112 /* Copy data to buffer */
113 profile_start ( &xferbuf_write_profiler );
114 xferbuf->op->write ( xferbuf, offset, data, len );
115 profile_stop ( &xferbuf_write_profiler );
121 * Read from data transfer buffer
123 * @v xferbuf Data transfer buffer
124 * @v offset Starting offset
125 * @v data Data to write
126 * @v len Length of data
128 int xferbuf_read ( struct xfer_buffer *xferbuf, size_t offset,
129 void *data, size_t len ) {
131 /* Check that read is within buffer range */
132 if ( ( offset > xferbuf->len ) ||
133 ( len > ( xferbuf->len - offset ) ) )
136 /* Copy data from buffer */
137 profile_start ( &xferbuf_read_profiler );
138 xferbuf->op->read ( xferbuf, offset, data, len );
139 profile_stop ( &xferbuf_read_profiler );
145 * Add received data to data transfer buffer
147 * @v xferbuf Data transfer buffer
148 * @v iobuf I/O buffer
149 * @v meta Data transfer metadata
150 * @ret rc Return status code
152 int xferbuf_deliver ( struct xfer_buffer *xferbuf, struct io_buffer *iobuf,
153 struct xfer_metadata *meta ) {
154 size_t len = iob_len ( iobuf );
158 /* Start profiling */
159 profile_start ( &xferbuf_deliver_profiler );
161 /* Calculate new buffer position */
163 if ( meta->flags & XFER_FL_ABS_OFFSET )
167 /* Write data to buffer */
168 if ( ( rc = xferbuf_write ( xferbuf, pos, iobuf->data, len ) ) != 0 )
171 /* Update current buffer position */
172 xferbuf->pos = ( pos + len );
176 profile_stop ( &xferbuf_deliver_profiler );
181 * Reallocate malloc()-based data buffer
183 * @v xferbuf Data transfer buffer
184 * @v len New length (or zero to free buffer)
185 * @ret rc Return status code
187 static int xferbuf_malloc_realloc ( struct xfer_buffer *xferbuf, size_t len ) {
190 new_data = realloc ( xferbuf->data, len );
193 xferbuf->data = new_data;
198 * Write data to malloc()-based data buffer
200 * @v xferbuf Data transfer buffer
201 * @v offset Starting offset
202 * @v data Data to copy
203 * @v len Length of data
205 static void xferbuf_malloc_write ( struct xfer_buffer *xferbuf, size_t offset,
206 const void *data, size_t len ) {
208 memcpy ( ( xferbuf->data + offset ), data, len );
212 * Read data from malloc()-based data buffer
214 * @v xferbuf Data transfer buffer
215 * @v offset Starting offset
216 * @v data Data to read
217 * @v len Length of data
219 static void xferbuf_malloc_read ( struct xfer_buffer *xferbuf, size_t offset,
220 void *data, size_t len ) {
222 memcpy ( data, ( xferbuf->data + offset ), len );
225 /** malloc()-based data buffer operations */
226 struct xfer_buffer_operations xferbuf_malloc_operations = {
227 .realloc = xferbuf_malloc_realloc,
228 .write = xferbuf_malloc_write,
229 .read = xferbuf_malloc_read,
233 * Reallocate umalloc()-based data buffer
235 * @v xferbuf Data transfer buffer
236 * @v len New length (or zero to free buffer)
237 * @ret rc Return status code
239 static int xferbuf_umalloc_realloc ( struct xfer_buffer *xferbuf, size_t len ) {
240 userptr_t *udata = xferbuf->data;
243 new_udata = urealloc ( *udata, len );
251 * Write data to umalloc()-based data buffer
253 * @v xferbuf Data transfer buffer
254 * @v offset Starting offset
255 * @v data Data to copy
256 * @v len Length of data
258 static void xferbuf_umalloc_write ( struct xfer_buffer *xferbuf, size_t offset,
259 const void *data, size_t len ) {
260 userptr_t *udata = xferbuf->data;
262 copy_to_user ( *udata, offset, data, len );
266 * Read data from umalloc()-based data buffer
268 * @v xferbuf Data transfer buffer
269 * @v offset Starting offset
270 * @v data Data to read
271 * @v len Length of data
273 static void xferbuf_umalloc_read ( struct xfer_buffer *xferbuf, size_t offset,
274 void *data, size_t len ) {
275 userptr_t *udata = xferbuf->data;
277 copy_from_user ( data, *udata, offset, len );
280 /** umalloc()-based data buffer operations */
281 struct xfer_buffer_operations xferbuf_umalloc_operations = {
282 .realloc = xferbuf_umalloc_realloc,
283 .write = xferbuf_umalloc_write,
284 .read = xferbuf_umalloc_read,
288 * Get underlying data transfer buffer
290 * @v interface Data transfer interface
291 * @ret xferbuf Data transfer buffer, or NULL on error
293 * This call will check that the xfer_buffer() handler belongs to the
294 * destination interface which also provides xfer_deliver() for this
297 * This is done to prevent accidental accesses to a data transfer
298 * buffer which may be located behind a non-transparent datapath via a
299 * series of pass-through interfaces.
301 struct xfer_buffer * xfer_buffer ( struct interface *intf ) {
302 struct interface *dest;
303 xfer_buffer_TYPE ( void * ) *op =
304 intf_get_dest_op ( intf, xfer_buffer, &dest );
305 void *object = intf_object ( dest );
306 struct interface *xfer_deliver_dest;
307 struct xfer_buffer *xferbuf;
309 /* Check that this operation is provided by the same interface
310 * which handles xfer_deliver().
312 ( void ) intf_get_dest_op ( intf, xfer_deliver, &xfer_deliver_dest );
314 if ( op && ( dest == xfer_deliver_dest ) ) {
315 xferbuf = op ( object );
317 /* Default is to not have a data transfer buffer */
321 intf_put ( xfer_deliver_dest );