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 * Attempt to fetch a pointer to @p io's internal read buffer, if 71 * supported by @p io. 72 * 73 * The returned pointer is only gauranteed to be valid until the next I/O 74 * operation performed on @p io; concrete implementations of bhnd_nvram_io 75 * may provide stronger gaurantees. 76 * 77 * @param io NVRAM I/O context. 78 * @param offset The offset within @p io for which to return a buffer pointer. 79 * @param[out] ptr On success, will be initialized with a pointer to @p io's 80 * internal read buffer. 81 * @param nbytes The minimum number of bytes that must be readable at @p offset. 82 * @param[out] navail The actual number of readable bytes, which may be greater 83 * than @p nbytes. If this value is not required, a NULL pointer may be 84 * provided. 85 * 86 * @retval 0 success 87 * @retval EIO if an input error occured reading @p io. 88 * @retval ENODEV if @p io does not support direct access to its backing read 89 * buffer. 90 * @retval ENXIO if the request exceeds the size of @p io. 91 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 92 * @p nbytes are misaligned. 93 */ 94 int 95 bhnd_nvram_io_read_ptr(struct bhnd_nvram_io *io, size_t offset, 96 const void **ptr, size_t nbytes, size_t *navail) 97 { 98 return (io->iops->read_ptr(io, offset, ptr, nbytes, navail)); 99 } 100 101 /** 102 * Write @p nbytes to @p io at @p offset. 103 * 104 * @param io NVRAM I/O context. 105 * @param offset The offset within @p io at which to perform the write. 106 * @param buffer Data to be written to @p io. 107 * @param nbytes The number of bytes to be written from @p buffer. 108 * 109 * @retval 0 success 110 * @retval EIO if an output error occurs writing to @p io. 111 * @retval ENODEV if @p io does not support writing. 112 * @retval ENXIO if @p io does not support writes beyond the existing 113 * end-of-file, and a write at @p offset would exceed the size of the @p io 114 * backing data store. 115 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 116 * @p nbytes are misaligned. 117 */ 118 int 119 bhnd_nvram_io_write(struct bhnd_nvram_io *io, size_t offset, void *buffer, 120 size_t nbytes) 121 { 122 return (io->iops->write(io, offset, buffer, nbytes)); 123 } 124 125 /** 126 * Attempt to fetch a writable pointer to @p io's internal write buffer, if 127 * supported by @p io. 128 * 129 * The returned pointer is only gauranteed to be valid until the next I/O 130 * operation performed on @p io; concrete implementations of bhnd_nvram_io 131 * may provide stronger gaurantees. 132 * 133 * @param io NVRAM I/O context. 134 * @param offset The offset within @p io for which to return a buffer pointer. 135 * @param[in,out] ptr On success, will be initialized with a pointer to @p io's 136 * internal buffer at which up to @p nbytes may be written. 137 * @param nbytes The minimum number of bytes that must be writable at @p offset. 138 * @param[out] navail The actual number of writable bytes, which may be greater 139 * than @p nbytes. If this value is not required, a NULL pointer may be 140 * provided. 141 * 142 * @retval 0 success 143 * @retval EIO if an output error occurs preparing @p io's write buffer. 144 * @retval ENODEV if @p io does not support direct access to its backing write 145 * buffer. 146 * @retval ENXIO if @p io does not support writes beyond the existing 147 * end-of-file, and a write at @p offset of @p nbytes would exceed the size of 148 * the @p io backing data store. 149 * @retval EFAULT if @p io requires I/O request alignment and @p offset or 150 * @p nbytes are misaligned. 151 */ 152 int 153 bhnd_nvram_io_write_ptr(struct bhnd_nvram_io *io, size_t offset, void **ptr, 154 size_t nbytes, size_t *navail) 155 { 156 return (io->iops->write_ptr(io, offset, ptr, nbytes, navail)); 157 } 158 159 /** 160 * Return the total number of bytes readable via @p io. 161 * 162 * @param io NVRAM I/O context. 163 */ 164 size_t 165 bhnd_nvram_io_getsize(struct bhnd_nvram_io *io) 166 { 167 return (io->iops->getsize(io)); 168 } 169 170 /** 171 * Attempt to set the size of @p io to @p size. 172 * 173 * If the total size of @p io is increased, the contents of the newly mapped 174 * bytes are undefined; concrete implementations of bhnd_nvram_io may 175 * provide stronger gaurantees. 176 * 177 * @param io NVRAM I/O context. 178 * @param size The new size. 179 * 180 * @retval 0 success 181 * @retval EIO if an I/O error occurs resizing @p io. 182 * @retval ENODEV if @p io does not support resizing. 183 * @retval ENXIO if @p size exceeds the capacity or other limits of @p io. 184 * @retval EFAULT if @p io requires I/O request alignment and @p size is 185 * misaligned. 186 */ 187 int 188 bhnd_nvram_io_setsize(struct bhnd_nvram_io *io, size_t size) 189 { 190 return (io->iops->setsize(io, size)); 191 } 192 193 /** 194 * Free a previously allocated I/O context, releasing all associated 195 * resources. 196 * 197 * @param io The I/O context to be freed. 198 */ 199 void 200 bhnd_nvram_io_free(struct bhnd_nvram_io *io) 201 { 202 return (io->iops->free(io)); 203 } 204