iPXE
nvs.c
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1 /*
2  * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
3  *
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 any later version.
8  *
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.
13  *
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
17  * 02110-1301, USA.
18  *
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.
22  */
23 
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25 
26 #include <stdint.h>
27 #include <string.h>
28 #include <errno.h>
29 #include <assert.h>
30 #include <ipxe/nvs.h>
31 
32 /** @file
33  *
34  * Non-volatile storage
35  *
36  */
37 
38 /**
39  * Calculate length up to next block boundary
40  *
41  * @v nvs NVS device
42  * @v address Starting address
43  * @v max_len Maximum length
44  * @ret len Length to use, stopping at block boundaries
45  */
46 static size_t nvs_frag_len ( struct nvs_device *nvs, unsigned int address,
47  size_t max_len ) {
48  size_t frag_len;
49 
50  /* If there are no block boundaries, return the maximum length */
51  if ( ! nvs->block_size )
52  return max_len;
53 
54  /* Calculate space remaining up to next block boundary */
55  frag_len = ( ( nvs->block_size -
56  ( address & ( nvs->block_size - 1 ) ) )
57  << nvs->word_len_log2 );
58 
59  /* Limit to maximum length */
60  if ( max_len < frag_len )
61  return max_len;
62 
63  return frag_len;
64 }
65 
66 /**
67  * Read from non-volatile storage device
68  *
69  * @v nvs NVS device
70  * @v address Address from which to read
71  * @v data Data buffer
72  * @v len Length of data buffer
73  * @ret rc Return status code
74  */
75 int nvs_read ( struct nvs_device *nvs, unsigned int address,
76  void *data, size_t len ) {
77  size_t frag_len;
78  int rc;
79 
80  /* We don't even attempt to handle buffer lengths that aren't
81  * an integral number of words.
82  */
83  assert ( ( len & ( ( 1 << nvs->word_len_log2 ) - 1 ) ) == 0 );
84 
85  while ( len ) {
86 
87  /* Calculate length to read, stopping at block boundaries */
88  frag_len = nvs_frag_len ( nvs, address, len );
89 
90  /* Read this portion of the buffer from the device */
91  if ( ( rc = nvs->read ( nvs, address, data, frag_len ) ) != 0 )
92  return rc;
93 
94  /* Update parameters */
95  data += frag_len;
96  address += ( frag_len >> nvs->word_len_log2 );
97  len -= frag_len;
98  }
99 
100  return 0;
101 }
102 
103 /**
104  * Verify content of non-volatile storage device
105  *
106  * @v nvs NVS device
107  * @v address Address from which to read
108  * @v data Data to compare against
109  * @v len Length of data buffer
110  * @ret rc Return status code
111  */
112 static int nvs_verify ( struct nvs_device *nvs, unsigned int address,
113  const void *data, size_t len ) {
114  uint8_t read_data[len];
115  int rc;
116 
117  /* Read data into temporary buffer */
118  if ( ( rc = nvs_read ( nvs, address, read_data, len ) ) != 0 )
119  return rc;
120 
121  /* Compare data */
122  if ( memcmp ( data, read_data, len ) != 0 ) {
123  DBG ( "NVS %p verification failed at %#04x+%zd\n",
124  nvs, address, len );
125  return -EIO;
126  }
127 
128  return 0;
129 }
130 
131 /**
132  * Write to non-volatile storage device
133  *
134  * @v nvs NVS device
135  * @v address Address to which to write
136  * @v data Data buffer
137  * @v len Length of data buffer
138  * @ret rc Return status code
139  */
140 int nvs_write ( struct nvs_device *nvs, unsigned int address,
141  const void *data, size_t len ) {
142  size_t frag_len;
143  int rc;
144 
145  /* We don't even attempt to handle buffer lengths that aren't
146  * an integral number of words.
147  */
148  assert ( ( len & ( ( 1 << nvs->word_len_log2 ) - 1 ) ) == 0 );
149 
150  while ( len ) {
151 
152  /* Calculate length to write, stopping at block boundaries */
153  frag_len = nvs_frag_len ( nvs, address, len );
154 
155  /* Write this portion of the buffer to the device */
156  if ( ( rc = nvs->write ( nvs, address, data, frag_len ) ) != 0)
157  return rc;
158 
159  /* Read back and verify data */
160  if ( ( rc = nvs_verify ( nvs, address, data, frag_len ) ) != 0)
161  return rc;
162 
163  /* Update parameters */
164  data += frag_len;
165  address += ( frag_len >> nvs->word_len_log2 );
166  len -= frag_len;
167  }
168 
169  return 0;
170 }
int(* write)(struct nvs_device *nvs, unsigned int address, const void *data, size_t len)
Write data to device.
Definition: nvs.h:59
struct arbelprm_rc_send_wqe rc
Definition: arbel.h:14
unsigned int word_len_log2
Word length.
Definition: nvs.h:22
Error codes.
uint16_t max_len
Maximum length (in bytes)
Definition: ntlm.h:18
A non-volatile storage device.
Definition: nvs.h:15
uint64_t address
Base address.
Definition: ena.h:24
int nvs_write(struct nvs_device *nvs, unsigned int address, const void *data, size_t len)
Write to non-volatile storage device.
Definition: nvs.c:140
Non-volatile storage.
static size_t nvs_frag_len(struct nvs_device *nvs, unsigned int address, size_t max_len)
Calculate length up to next block boundary.
Definition: nvs.c:46
unsigned int block_size
Data block size (in words)
Definition: nvs.h:36
Assertions.
assert((readw(&hdr->flags) &(GTF_reading|GTF_writing))==0)
int(* read)(struct nvs_device *nvs, unsigned int address, void *data, size_t len)
Read data from device.
Definition: nvs.h:47
unsigned char uint8_t
Definition: stdint.h:10
uint32_t len
Length.
Definition: ena.h:14
#define EIO
Input/output error.
Definition: errno.h:433
FILE_LICENCE(GPL2_OR_LATER_OR_UBDL)
uint8_t data[48]
Additional event data.
Definition: ena.h:22
int nvs_read(struct nvs_device *nvs, unsigned int address, void *data, size_t len)
Read from non-volatile storage device.
Definition: nvs.c:75
#define DBG(...)
Print a debugging message.
Definition: compiler.h:498
static int nvs_verify(struct nvs_device *nvs, unsigned int address, const void *data, size_t len)
Verify content of non-volatile storage device.
Definition: nvs.c:112
int memcmp(const void *first, const void *second, size_t len)
Compare memory regions.
Definition: string.c:114
String functions.