1/** @file 2 BlockIo implementation for Xen PV Block driver. 3 4 This file is implementing the interface between the actual driver in 5 BlockFront.c to the BlockIo protocol. 6 7 Copyright (C) 2014, Citrix Ltd. 8 9 This program and the accompanying materials 10 are licensed and made available under the terms and conditions of the BSD License 11 which accompanies this distribution. The full text of the license may be found at 12 http://opensource.org/licenses/bsd-license.php 13 14 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 15 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 16 17**/ 18 19#include "XenPvBlkDxe.h" 20 21#include "BlockFront.h" 22 23/// 24/// Block I/O Media structure 25/// 26GLOBAL_REMOVE_IF_UNREFERENCED 27EFI_BLOCK_IO_MEDIA gXenPvBlkDxeBlockIoMedia = { 28 0, // MediaId 29 FALSE, // RemovableMedia 30 FALSE, // MediaPresent 31 FALSE, // LogicalPartition 32 TRUE, // ReadOnly 33 FALSE, // WriteCaching 34 512, // BlockSize 35 512, // IoAlign, BlockFront does not support less than 512 bits-aligned. 36 0, // LastBlock 37 0, // LowestAlignedLba 38 0, // LogicalBlocksPerPhysicalBlock 39 0 // OptimalTransferLengthGranularity 40}; 41 42/// 43/// Block I/O Protocol instance 44/// 45GLOBAL_REMOVE_IF_UNREFERENCED 46EFI_BLOCK_IO_PROTOCOL gXenPvBlkDxeBlockIo = { 47 EFI_BLOCK_IO_PROTOCOL_REVISION3, // Revision 48 &gXenPvBlkDxeBlockIoMedia, // Media 49 XenPvBlkDxeBlockIoReset, // Reset 50 XenPvBlkDxeBlockIoReadBlocks, // ReadBlocks 51 XenPvBlkDxeBlockIoWriteBlocks, // WriteBlocks 52 XenPvBlkDxeBlockIoFlushBlocks // FlushBlocks 53}; 54 55 56 57 58/** 59 Read/Write BufferSize bytes from Lba into Buffer. 60 61 This function is commun to XenPvBlkDxeBlockIoReadBlocks and 62 XenPvBlkDxeBlockIoWriteBlocks. 63 64 @param This Indicates a pointer to the calling context. 65 @param MediaId Id of the media, changes every time the media is replaced. 66 @param Lba The starting Logical Block Address to read from/write to. 67 @param BufferSize Size of Buffer, must be a multiple of device block size. 68 @param Buffer A pointer to the destination/source buffer for the data. 69 @param IsWrite Indicate if the operation is write or read. 70 71 @return See description of XenPvBlkDxeBlockIoReadBlocks and 72 XenPvBlkDxeBlockIoWriteBlocks. 73**/ 74STATIC 75EFI_STATUS 76XenPvBlkDxeBlockIoReadWriteBlocks ( 77 IN EFI_BLOCK_IO_PROTOCOL *This, 78 IN UINT32 MediaId, 79 IN EFI_LBA Lba, 80 IN UINTN BufferSize, 81 IN OUT VOID *Buffer, 82 IN BOOLEAN IsWrite 83 ) 84{ 85 XEN_BLOCK_FRONT_IO IoData; 86 EFI_BLOCK_IO_MEDIA *Media = This->Media; 87 UINTN Sector; 88 EFI_STATUS Status; 89 90 if (Buffer == NULL) { 91 return EFI_INVALID_PARAMETER; 92 } 93 if (BufferSize == 0) { 94 return EFI_SUCCESS; 95 } 96 97 if (BufferSize % Media->BlockSize != 0) { 98 DEBUG ((EFI_D_ERROR, "XenPvBlkDxe: Bad buffer size: 0x%Lx\n", 99 (UINT64)BufferSize)); 100 return EFI_BAD_BUFFER_SIZE; 101 } 102 103 if (Lba > Media->LastBlock || 104 (BufferSize / Media->BlockSize) - 1 > Media->LastBlock - Lba) { 105 DEBUG ((EFI_D_ERROR, 106 "XenPvBlkDxe: %a with invalid LBA: 0x%Lx, size: 0x%Lx\n", 107 IsWrite ? "Write" : "Read", Lba, (UINT64)BufferSize)); 108 return EFI_INVALID_PARAMETER; 109 } 110 111 if (IsWrite && Media->ReadOnly) { 112 return EFI_WRITE_PROTECTED; 113 } 114 115 if ((Media->IoAlign > 1) && (UINTN)Buffer & (Media->IoAlign - 1)) { 116 // 117 // Grub2 does not appear to respect IoAlign of 512, so reallocate the 118 // buffer here. 119 // 120 VOID *NewBuffer; 121 122 // 123 // Try again with a properly aligned buffer. 124 // 125 NewBuffer = AllocateAlignedPages((BufferSize + EFI_PAGE_SIZE) / EFI_PAGE_SIZE, 126 Media->IoAlign); 127 if (!IsWrite) { 128 Status = XenPvBlkDxeBlockIoReadBlocks (This, MediaId, 129 Lba, BufferSize, NewBuffer); 130 CopyMem (Buffer, NewBuffer, BufferSize); 131 } else { 132 CopyMem (NewBuffer, Buffer, BufferSize); 133 Status = XenPvBlkDxeBlockIoWriteBlocks (This, MediaId, 134 Lba, BufferSize, NewBuffer); 135 } 136 FreeAlignedPages (NewBuffer, (BufferSize + EFI_PAGE_SIZE) / EFI_PAGE_SIZE); 137 return Status; 138 } 139 140 IoData.Dev = XEN_BLOCK_FRONT_FROM_BLOCK_IO (This); 141 Sector = (UINTN)MultU64x32 (Lba, Media->BlockSize / 512); 142 143 while (BufferSize > 0) { 144 if (((UINTN)Buffer & EFI_PAGE_MASK) == 0) { 145 IoData.Size = MIN (BLKIF_MAX_SEGMENTS_PER_REQUEST * EFI_PAGE_SIZE, 146 BufferSize); 147 } else { 148 IoData.Size = MIN ((BLKIF_MAX_SEGMENTS_PER_REQUEST - 1) * EFI_PAGE_SIZE, 149 BufferSize); 150 } 151 152 IoData.Buffer = Buffer; 153 IoData.Sector = Sector; 154 BufferSize -= IoData.Size; 155 Buffer = (VOID*) ((UINTN) Buffer + IoData.Size); 156 Sector += IoData.Size / 512; 157 Status = XenPvBlockIo (&IoData, IsWrite); 158 if (EFI_ERROR (Status)) { 159 DEBUG ((EFI_D_ERROR, "XenPvBlkDxe: Error durring %a operation.\n", 160 IsWrite ? "write" : "read")); 161 return Status; 162 } 163 } 164 return EFI_SUCCESS; 165} 166 167 168/** 169 Read BufferSize bytes from Lba into Buffer. 170 171 @param This Indicates a pointer to the calling context. 172 @param MediaId Id of the media, changes every time the media is replaced. 173 @param Lba The starting Logical Block Address to read from 174 @param BufferSize Size of Buffer, must be a multiple of device block size. 175 @param Buffer A pointer to the destination buffer for the data. The caller is 176 responsible for either having implicit or explicit ownership of the buffer. 177 178 @retval EFI_SUCCESS The data was read correctly from the device. 179 @retval EFI_DEVICE_ERROR The device reported an error while performing the read. 180 @retval EFI_NO_MEDIA There is no media in the device. 181 @retval EFI_MEDIA_CHANGED The MediaId does not matched the current device. 182 @retval EFI_BAD_BUFFER_SIZE The Buffer was not a multiple of the block size of the device. 183 @retval EFI_INVALID_PARAMETER The read request contains LBAs that are not valid, 184 or the buffer is not on proper alignment. 185 186**/ 187EFI_STATUS 188EFIAPI 189XenPvBlkDxeBlockIoReadBlocks ( 190 IN EFI_BLOCK_IO_PROTOCOL *This, 191 IN UINT32 MediaId, 192 IN EFI_LBA Lba, 193 IN UINTN BufferSize, 194 OUT VOID *Buffer 195 ) 196{ 197 return XenPvBlkDxeBlockIoReadWriteBlocks (This, 198 MediaId, Lba, BufferSize, Buffer, FALSE); 199} 200 201/** 202 Write BufferSize bytes from Lba into Buffer. 203 204 @param This Indicates a pointer to the calling context. 205 @param MediaId The media ID that the write request is for. 206 @param Lba The starting logical block address to be written. The caller is 207 responsible for writing to only legitimate locations. 208 @param BufferSize Size of Buffer, must be a multiple of device block size. 209 @param Buffer A pointer to the source buffer for the data. 210 211 @retval EFI_SUCCESS The data was written correctly to the device. 212 @retval EFI_WRITE_PROTECTED The device can not be written to. 213 @retval EFI_DEVICE_ERROR The device reported an error while performing the write. 214 @retval EFI_NO_MEDIA There is no media in the device. 215 @retval EFI_MEDIA_CHNAGED The MediaId does not matched the current device. 216 @retval EFI_BAD_BUFFER_SIZE The Buffer was not a multiple of the block size of the device. 217 @retval EFI_INVALID_PARAMETER The write request contains LBAs that are not valid, 218 or the buffer is not on proper alignment. 219 220**/ 221EFI_STATUS 222EFIAPI 223XenPvBlkDxeBlockIoWriteBlocks ( 224 IN EFI_BLOCK_IO_PROTOCOL *This, 225 IN UINT32 MediaId, 226 IN EFI_LBA Lba, 227 IN UINTN BufferSize, 228 IN VOID *Buffer 229 ) 230{ 231 return XenPvBlkDxeBlockIoReadWriteBlocks (This, 232 MediaId, Lba, BufferSize, Buffer, TRUE); 233} 234 235/** 236 Flush the Block Device. 237 238 @param This Indicates a pointer to the calling context. 239 240 @retval EFI_SUCCESS All outstanding data was written to the device 241 @retval EFI_DEVICE_ERROR The device reported an error while writting back the data 242 @retval EFI_NO_MEDIA There is no media in the device. 243 244**/ 245EFI_STATUS 246EFIAPI 247XenPvBlkDxeBlockIoFlushBlocks ( 248 IN EFI_BLOCK_IO_PROTOCOL *This 249 ) 250{ 251 XenPvBlockSync (XEN_BLOCK_FRONT_FROM_BLOCK_IO (This)); 252 return EFI_SUCCESS; 253} 254 255/** 256 Reset the block device hardware. 257 258 @param[in] This Indicates a pointer to the calling context. 259 @param[in] ExtendedVerification Not used. 260 261 @retval EFI_SUCCESS The device was reset. 262 263**/ 264EFI_STATUS 265EFIAPI 266XenPvBlkDxeBlockIoReset ( 267 IN EFI_BLOCK_IO_PROTOCOL *This, 268 IN BOOLEAN ExtendedVerification 269 ) 270{ 271 // 272 // Since the initialization of the devices is done, then the device is 273 // working correctly. 274 // 275 return EFI_SUCCESS; 276} 277