From f33f01c126dc15836fd0111c6e3175c6279c0193 Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Sat, 13 May 2006 11:37:50 +0000 Subject: [PATCH] Defined SCSI device interface, and added SCSI block device implementation. --- src/drivers/block/scsi.c | 142 +++++++++++++++++++++++++++++++++++++ src/include/gpxe/scsi.h | 148 ++++++++++++++++++++++++++++++++++++--- 2 files changed, 281 insertions(+), 9 deletions(-) create mode 100644 src/drivers/block/scsi.c diff --git a/src/drivers/block/scsi.c b/src/drivers/block/scsi.c new file mode 100644 index 00000000..7ddc4a11 --- /dev/null +++ b/src/drivers/block/scsi.c @@ -0,0 +1,142 @@ +/* + * Copyright (C) 2006 Michael Brown . + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include +#include +#include +#include +#include + +/** @file + * + * SCSI block device + * + */ + +static inline __attribute__ (( always_inline )) struct scsi_device * +block_to_scsi ( struct block_device *blockdev ) { + return container_of ( blockdev, struct scsi_device, blockdev ); +} + +/** + * Issue SCSI command + * + * @v scsi SCSI device + * @v command SCSI command + * @ret rc Return status code + */ +static int scsi_command ( struct scsi_device *scsi, + struct scsi_command *command ) { + return scsi->command ( scsi, command ); +} + +/** + * Read block from SCSI device + * + * @v blockdev Block device + * @v block LBA block number + * @v buffer Data buffer + * @ret rc Return status code + */ +static int scsi_read ( struct block_device *blockdev, uint64_t block, + void *buffer ) { + struct scsi_device *scsi = block_to_scsi ( blockdev ); + struct scsi_command command; + struct scsi_cdb_read_16 *cdb = &command.cdb.read16; + + /* Issue READ (16) */ + memset ( &command, 0, sizeof ( command ) ); + cdb->opcode = SCSI_OPCODE_READ_16; + cdb->lba = cpu_to_be64 ( block ); + cdb->len = cpu_to_be32 ( 1 ); /* always a single block */ + command.data_in = buffer; + command.data_in_len = blockdev->blksize; + return scsi_command ( scsi, &command ); +} + +/** + * Write block to SCSI device + * + * @v blockdev Block device + * @v block LBA block number + * @v buffer Data buffer + * @ret rc Return status code + */ +static int scsi_write ( struct block_device *blockdev, uint64_t block, + const void *buffer ) { + struct scsi_device *scsi = block_to_scsi ( blockdev ); + struct scsi_command command; + struct scsi_cdb_write_16 *cdb = &command.cdb.write16; + + /* Issue WRITE (16) */ + memset ( &command, 0, sizeof ( command ) ); + cdb->opcode = SCSI_OPCODE_WRITE_16; + cdb->lba = cpu_to_be64 ( block ); + cdb->len = cpu_to_be32 ( 1 ); /* always a single block */ + command.data_out = buffer; + command.data_out_len = blockdev->blksize; + return scsi_command ( scsi, &command ); +} + +/** + * Read capacity of SCSI device + * + * @v blockdev Block device + * @ret rc Return status code + */ +static int scsi_read_capacity ( struct block_device *blockdev ) { + struct scsi_device *scsi = block_to_scsi ( blockdev ); + struct scsi_command command; + struct scsi_cdb_read_capacity_16 *cdb = &command.cdb.readcap16; + struct scsi_capacity_16 capacity; + int rc; + + /* Issue READ CAPACITY (16) */ + memset ( &command, 0, sizeof ( command ) ); + cdb->opcode = SCSI_OPCODE_SERVICE_ACTION_IN; + cdb->service_action = SCSI_SERVICE_ACTION_READ_CAPACITY_16; + cdb->len = cpu_to_be32 ( sizeof ( capacity ) ); + command.data_in = &capacity; + command.data_in_len = sizeof ( capacity ); + + if ( ( rc = scsi_command ( scsi, &command ) ) != 0 ) + return rc; + + /* Fill in block device fields */ + blockdev->blksize = be32_to_cpu ( capacity.blksize ); + blockdev->blocks = ( be64_to_cpu ( capacity.lba ) + 1 ); + return 0; +} + +/** + * Initialise SCSI device + * + * @v scsi SCSI device + * @ret rc Return status code + * + * Initialises a SCSI device. The scsi_device::command and + * scsi_device::lun fields must already be filled in. This function + * will configure scsi_device::blockdev, including issuing a READ + * CAPACITY call to determine the block size and total device size. + */ +int init_scsidev ( struct scsi_device *scsi ) { + /** Fill in read and write methods, and get device capacity */ + scsi->blockdev.read = scsi_read; + scsi->blockdev.write = scsi_write; + return scsi_read_capacity ( &scsi->blockdev ); +} diff --git a/src/include/gpxe/scsi.h b/src/include/gpxe/scsi.h index be71bab3..db57e891 100644 --- a/src/include/gpxe/scsi.h +++ b/src/include/gpxe/scsi.h @@ -2,9 +2,39 @@ #define _GPXE_SCSI_H #include +#include -struct scsi_cdb_read_10 { - /** Opcode */ +/** + * @defgroup scsiops SCSI operation codes + * @{ + */ + +#define SCSI_OPCODE_READ_16 0x88 /**< READ (16) */ +#define SCSI_OPCODE_WRITE_16 0x8a /**< WRITE (16) */ +#define SCSI_OPCODE_SERVICE_ACTION_IN 0x9e /**< SERVICE ACTION IN */ +#define SCSI_SERVICE_ACTION_READ_CAPACITY_16 0x10 /**< READ CAPACITY (16) */ + +/** @} */ + +/** + * @defgroup scsiflags SCSI flags + * @{ + */ + +#define SCSI_FL_FUA_NV 0x02 /**< Force unit access to NVS */ +#define SCSI_FL_FUA 0x08 /**< Force unit access */ +#define SCSI_FL_DPO 0x10 /**< Disable cache page out */ + +/** @} */ + +/** + * @defgroup scsicdbs SCSI command data blocks + * @{ + */ + +/** A SCSI "READ (16)" CDB */ +struct scsi_cdb_read_16 { + /** Opcode (0x88) */ uint8_t opcode; /** Flags */ uint8_t flags; @@ -12,23 +42,123 @@ struct scsi_cdb_read_10 { * * This is a logical block number, in big-endian order. */ - uint32_t lba; - /** Group number */ - uint8_t group; + uint64_t lba; /** Transfer length * - * This is a logical block count. + * This is a logical block count, in big-endian order. */ - uint16_t len; + uint32_t len; + /** Group number */ + uint8_t group; /** Control byte */ uint8_t control; } __attribute__ (( packed )); -#define SCSI_OPCODE_READ_10 0x28 +/** A SCSI "WRITE (16)" CDB */ +struct scsi_cdb_write_16 { + /** Opcode (0x8a) */ + uint8_t opcode; + /** Flags */ + uint8_t flags; + /** Start address + * + * This is a logical block number, in big-endian order. + */ + uint64_t lba; + /** Transfer length + * + * This is a logical block count, in big-endian order. + */ + uint32_t len; + /** Group number */ + uint8_t group; + /** Control byte */ + uint8_t control; +} __attribute__ (( packed )); +/** A SCSI "READ CAPACITY (16)" CDB */ +struct scsi_cdb_read_capacity_16 { + /** Opcode (0x9e) */ + uint8_t opcode; + /** Service action */ + uint8_t service_action; + /** Logical block address + * + * Applicable only if the PMI bit is set. + */ + uint64_t lba; + /** Transfer length + * + * This is the size of the data-in buffer, in bytes. + */ + uint32_t len; + /** Reserved */ + uint8_t reserved; + /** Control byte */ + uint8_t control; +} __attribute__ (( packed )); + +/** SCSI "READ CAPACITY (16)" parameter data */ +struct scsi_capacity_16 { + /** Maximum logical block number */ + uint64_t lba; + /** Block length in bytes */ + uint32_t blksize; + /** Reserved */ + uint8_t reserved[20]; +} __attribute__ (( packed )); + +/** A SCSI Command Data Block */ union scsi_cdb { - struct scsi_cdb_read_10 read_10; + struct scsi_cdb_read_16 read16; + struct scsi_cdb_write_16 write16; + struct scsi_cdb_read_capacity_16 readcap16; char bytes[16]; }; +/** @} */ + +/** A SCSI command */ +struct scsi_command { + /** CDB for this command */ + union scsi_cdb cdb; + /** Data-out buffer (may be NULL) */ + const void *data_out; + /** Data-out buffer length + * + * Must be zero if @c data_out is NULL + */ + size_t data_out_len; + /** Data-in buffer (may be NULL) */ + void *data_in; + /** Data-in buffer length + * + * Must be zero if @c data_in is NULL + */ + size_t data_in_len; +}; + +/** A SCSI device */ +struct scsi_device { + /** Block device interface */ + struct block_device blockdev; + /** Logical unit number (LUN) + * + * This is a four-level LUN as specified by SAM-2, in + * big-endian order. + */ + uint64_t lun; + /** + * Issue SCSI command + * + * @v scsi SCSI device + * @v command SCSI command + * @ret rc Return status code + */ + int ( * command ) ( struct scsi_device *scsi, + struct scsi_command *command ); +}; + +extern int init_scsidev ( struct scsi_device *scsi ); + #endif /* _GPXE_SCSI_H */