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 #ifdef _KERNEL 32 #include <sys/param.h> 33 #else /* !_KERNEL */ 34 #include <errno.h> 35 #include <stdint.h> 36 #include <stdlib.h> 37 #endif /* _KERNEL */ 38 39 #include "bhnd_nvram_io.h" 40 #include "bhnd_nvram_iovar.h" 41 42 /** 43 * Read exactly @p nbytes from @p io at @p offset. 44 * 45 * @param io NVRAM I/O context. 46 * @param offset The offset within @p io at which to perform the read. 47 * @param[out] buffer Output buffer to which @p nbytes from @p io will be 48 * written. 49 * @param nbytes The maximum number of bytes to be read from @p io. 50 * 51 * @retval 0 success 52 * @retval EIO if an input error occurred reading @p io. 53 * @retval ENXIO if the request for @p offset or @p nbytes exceeds the size 54 * of @p io. 55 * @retval EFAULT if @p io requires I/O request alignment and @p offset is 56 * misaligned. 57 * @retval EFAULT if @p io requires I/O request alignment and @p nbytes is 58 * misaligned and cannot be rounded down to an aligned non-zero value. 59 */ 60 int 61 bhnd_nvram_io_read(struct bhnd_nvram_io *io, size_t offset, void *buffer, 62 size_t nbytes) 63 { 64 return (io->iops->read(io, offset, buffer, nbytes)); 65 } 66 67 /** 68 * Attempt to fetch a pointer to @p io's internal read buffer, if 69 * supported by @p io. 70 * 71 * The returned pointer is only gauranteed to be valid until the next I/O 72 * operation performed on @p io; concrete implementations of bhnd_nvram_io 73 * may provide stronger gaurantees. 74 * 75 * @param io NVRAM I/O context. 76 * @param offset The offset within @p io for which to return a buffer pointer. 77 * @param[out] ptr On success, will be initialized with a pointer to @p io's 78 * internal read buffer. 79 * @param nbytes The minimum number of bytes that must be readable at @p offset. 80 * @param[out] navail The actual number of readable bytes, which may be greater 81 * than @p nbytes. If this value is not required, a NULL pointer may be 82 * provided. 83 * 84 * @retval 0 success 85 * @retval EIO if an input error occurred reading @p io. 86 * @retval ENODEV if @p io does not support direct access to its backing read 87 * buffer. 88 * @retval ENXIO if the request exceeds the size of @p io. 89 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 90 * @p nbytes are misaligned. 91 */ 92 int 93 bhnd_nvram_io_read_ptr(struct bhnd_nvram_io *io, size_t offset, 94 const void **ptr, size_t nbytes, size_t *navail) 95 { 96 return (io->iops->read_ptr(io, offset, ptr, nbytes, navail)); 97 } 98 99 /** 100 * Write @p nbytes to @p io at @p offset. 101 * 102 * @param io NVRAM I/O context. 103 * @param offset The offset within @p io at which to perform the write. 104 * @param buffer Data to be written to @p io. 105 * @param nbytes The number of bytes to be written from @p buffer. 106 * 107 * @retval 0 success 108 * @retval EIO if an output error occurs writing to @p io. 109 * @retval ENODEV if @p io does not support writing. 110 * @retval ENXIO if @p io does not support writes beyond the existing 111 * end-of-file, and a write at @p offset would exceed the size of the @p io 112 * backing data store. 113 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 114 * @p nbytes are misaligned. 115 */ 116 int 117 bhnd_nvram_io_write(struct bhnd_nvram_io *io, size_t offset, void *buffer, 118 size_t nbytes) 119 { 120 return (io->iops->write(io, offset, buffer, nbytes)); 121 } 122 123 /** 124 * Attempt to fetch a writable pointer to @p io's internal write buffer, if 125 * supported by @p io. 126 * 127 * The returned pointer is only gauranteed to be valid until the next I/O 128 * operation performed on @p io; concrete implementations of bhnd_nvram_io 129 * may provide stronger gaurantees. 130 * 131 * @param io NVRAM I/O context. 132 * @param offset The offset within @p io for which to return a buffer pointer. 133 * @param[in,out] ptr On success, will be initialized with a pointer to @p io's 134 * internal buffer at which up to @p nbytes may be written. 135 * @param nbytes The minimum number of bytes that must be writable at @p offset. 136 * @param[out] navail The actual number of writable bytes, which may be greater 137 * than @p nbytes. If this value is not required, a NULL pointer may be 138 * provided. 139 * 140 * @retval 0 success 141 * @retval EIO if an output error occurs preparing @p io's write buffer. 142 * @retval ENODEV if @p io does not support direct access to its backing write 143 * buffer. 144 * @retval ENXIO if @p io does not support writes beyond the existing 145 * end-of-file, and a write at @p offset of @p nbytes would exceed the size of 146 * the @p io backing data store. 147 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 148 * @p nbytes are misaligned. 149 */ 150 int 151 bhnd_nvram_io_write_ptr(struct bhnd_nvram_io *io, size_t offset, void **ptr, 152 size_t nbytes, size_t *navail) 153 { 154 return (io->iops->write_ptr(io, offset, ptr, nbytes, navail)); 155 } 156 157 /** 158 * Return the total number of bytes readable via @p io. 159 * 160 * @param io NVRAM I/O context. 161 */ 162 size_t 163 bhnd_nvram_io_getsize(struct bhnd_nvram_io *io) 164 { 165 return (io->iops->getsize(io)); 166 } 167 168 /** 169 * Attempt to set the size of @p io to @p size. 170 * 171 * If the total size of @p io is increased, the contents of the newly mapped 172 * bytes are undefined; concrete implementations of bhnd_nvram_io may 173 * provide stronger gaurantees. 174 * 175 * @param io NVRAM I/O context. 176 * @param size The new size. 177 * 178 * @retval 0 success 179 * @retval EIO if an I/O error occurs resizing @p io. 180 * @retval ENODEV if @p io does not support resizing. 181 * @retval ENXIO if @p size exceeds the capacity or other limits of @p io. 182 * @retval EFAULT if @p io requires I/O request alignment and @p size is 183 * misaligned. 184 */ 185 int 186 bhnd_nvram_io_setsize(struct bhnd_nvram_io *io, size_t size) 187 { 188 return (io->iops->setsize(io, size)); 189 } 190 191 /** 192 * Free a previously allocated I/O context, releasing all associated 193 * resources. 194 * 195 * @param io The I/O context to be freed. 196 */ 197 void 198 bhnd_nvram_io_free(struct bhnd_nvram_io *io) 199 { 200 return (io->iops->free(io)); 201 } 202