1 /*- 2 * Copyright (c) 2016 Landon Fuller <landonf@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer, 10 * without modification. 11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 12 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 13 * redistribution must be conditioned upon including a substantially 14 * similar Disclaimer requirement for further binary redistribution. 15 * 16 * NO WARRANTY 17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 20 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 21 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 22 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 25 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 27 * THE POSSIBILITY OF SUCH DAMAGES. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #ifdef _KERNEL 34 #include <sys/param.h> 35 #else /* !_KERNEL */ 36 #include <errno.h> 37 #include <stdint.h> 38 #include <stdlib.h> 39 #endif /* _KERNEL */ 40 41 #include "bhnd_nvram_io.h" 42 #include "bhnd_nvram_iovar.h" 43 44 /** 45 * Read exactly @p nbytes from @p io at @p offset. 46 * 47 * @param io NVRAM I/O context. 48 * @param offset The offset within @p io at which to perform the read. 49 * @param[out] buffer Output buffer to which @p nbytes from @p io will be 50 * written. 51 * @param nbytes The maximum number of bytes to be read from @p io. 52 * 53 * @retval 0 success 54 * @retval EIO if an input error occured reading @p io. 55 * @retval ENXIO if the request for @p offset or @p nbytes exceeds the size 56 * of @p io. 57 * @retval EFAULT if @p io requires I/O request alignment and @p offset is 58 * misaligned. 59 * @retval EFAULT if @p io requires I/O request alignment and @p nbytes is 60 * misaligned and cannot be rounded down to an aligned non-zero value. 61 */ 62 int 63 bhnd_nvram_io_read(struct bhnd_nvram_io *io, size_t offset, void *buffer, 64 size_t nbytes) 65 { 66 return (io->iops->read(io, offset, buffer, nbytes)); 67 } 68 69 70 /** 71 * Attempt to fetch a pointer to @p io's internal read buffer, if 72 * supported by @p io. 73 * 74 * The returned pointer is only gauranteed to be valid until the next I/O 75 * operation performed on @p io; concrete implementations of bhnd_nvram_io 76 * may provide stronger gaurantees. 77 * 78 * @param io NVRAM I/O context. 79 * @param offset The offset within @p io for which to return a buffer pointer. 80 * @param[out] ptr On success, will be initialized with a pointer to @p io's 81 * internal read buffer. 82 * @param nbytes The minimum number of bytes that must be readable at @p offset. 83 * @param[out] navail The actual number of readable bytes, which may be greater 84 * than @p nbytes. If this value is not required, a NULL pointer may be 85 * provided. 86 * 87 * @retval 0 success 88 * @retval EIO if an input error occured reading @p io. 89 * @retval ENODEV if @p io does not support direct access to its backing read 90 * buffer. 91 * @retval ENXIO if the request exceeds the size of @p io. 92 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 93 * @p nbytes are misaligned. 94 */ 95 int 96 bhnd_nvram_io_read_ptr(struct bhnd_nvram_io *io, size_t offset, 97 const void **ptr, size_t nbytes, size_t *navail) 98 { 99 return (io->iops->read_ptr(io, offset, ptr, nbytes, navail)); 100 } 101 102 /** 103 * Write @p nbytes to @p io at @p offset. 104 * 105 * @param io NVRAM I/O context. 106 * @param offset The offset within @p io at which to perform the write. 107 * @param buffer Data to be written to @p io. 108 * @param nbytes The number of bytes to be written from @p buffer. 109 * 110 * @retval 0 success 111 * @retval EIO if an output error occurs writing to @p io. 112 * @retval ENODEV if @p io does not support writing. 113 * @retval ENXIO if @p io does not support writes beyond the existing 114 * end-of-file, and a write at @p offset would exceed the size of the @p io 115 * backing data store. 116 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 117 * @p nbytes are misaligned. 118 */ 119 int 120 bhnd_nvram_io_write(struct bhnd_nvram_io *io, size_t offset, void *buffer, 121 size_t nbytes) 122 { 123 return (io->iops->write(io, offset, buffer, nbytes)); 124 } 125 126 /** 127 * Attempt to fetch a writable pointer to @p io's internal write buffer, if 128 * supported by @p io. 129 * 130 * The returned pointer is only gauranteed to be valid until the next I/O 131 * operation performed on @p io; concrete implementations of bhnd_nvram_io 132 * may provide stronger gaurantees. 133 * 134 * @param io NVRAM I/O context. 135 * @param offset The offset within @p io for which to return a buffer pointer. 136 * @param[in,out] ptr On success, will be initialized with a pointer to @p io's 137 * internal buffer at which up to @p nbytes may be written. 138 * @param nbytes The minimum number of bytes that must be writable at @p offset. 139 * @param[out] navail The actual number of writable bytes, which may be greater 140 * than @p nbytes. If this value is not required, a NULL pointer may be 141 * provided. 142 * 143 * @retval 0 success 144 * @retval EIO if an output error occurs preparing @p io's write buffer. 145 * @retval ENODEV if @p io does not support direct access to its backing write 146 * buffer. 147 * @retval ENXIO if @p io does not support writes beyond the existing 148 * end-of-file, and a write at @p offset of @p nbytes would exceed the size of 149 * the @p io backing data store. 150 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 151 * @p nbytes are misaligned. 152 */ 153 int 154 bhnd_nvram_io_write_ptr(struct bhnd_nvram_io *io, size_t offset, void **ptr, 155 size_t nbytes, size_t *navail) 156 { 157 return (io->iops->write_ptr(io, offset, ptr, nbytes, navail)); 158 } 159 160 /** 161 * Return the total number of bytes readable via @p io. 162 * 163 * @param io NVRAM I/O context. 164 */ 165 size_t 166 bhnd_nvram_io_getsize(struct bhnd_nvram_io *io) 167 { 168 return (io->iops->getsize(io)); 169 } 170 171 /** 172 * Attempt to set the size of @p io to @p size. 173 * 174 * If the total size of @p io is increased, the contents of the newly mapped 175 * bytes are undefined; concrete implementations of bhnd_nvram_io may 176 * provide stronger gaurantees. 177 * 178 * @param io NVRAM I/O context. 179 * @param size The new size. 180 * 181 * @retval 0 success 182 * @retval EIO if an I/O error occurs resizing @p io. 183 * @retval ENODEV if @p io does not support resizing. 184 * @retval ENXIO if @p size exceeds the capacity or other limits of @p io. 185 * @retval EFAULT if @p io requires I/O request alignment and @p size is 186 * misaligned. 187 */ 188 int 189 bhnd_nvram_io_setsize(struct bhnd_nvram_io *io, size_t size) 190 { 191 return (io->iops->setsize(io, size)); 192 } 193 194 /** 195 * Free a previously allocated I/O context, releasing all associated 196 * resources. 197 * 198 * @param io The I/O context to be freed. 199 */ 200 void 201 bhnd_nvram_io_free(struct bhnd_nvram_io *io) 202 { 203 return (io->iops->free(io)); 204 } 205 206