blob: e49a3f92df4cca25abe91ccbbdb60484bfbaf0d9 [file] [log] [blame]
/*
* Copyright (C) 2017 Michael Brown <mbrown@fensystems.co.uk>.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
/**
* @file
*
* SAN booting
*
*/
#include <stdint.h>
#include <stdlib.h>
#include <errno.h>
#include <assert.h>
#include <ipxe/xfer.h>
#include <ipxe/open.h>
#include <ipxe/timer.h>
#include <ipxe/process.h>
#include <ipxe/iso9660.h>
#include <ipxe/dhcp.h>
#include <ipxe/settings.h>
#include <ipxe/quiesce.h>
#include <ipxe/sanboot.h>
/**
* Timeout for block device commands (in ticks)
*
* Underlying devices should ideally never become totally stuck.
* However, if they do, then the blocking SAN APIs provide no means
* for the caller to cancel the operation, and the machine appears to
* hang. Use an overall timeout for all commands to avoid this
* problem and bounce timeout failures to the caller.
*/
#define SAN_COMMAND_TIMEOUT ( 15 * TICKS_PER_SEC )
/**
* Default number of times to retry commands
*
* We may need to retry commands. For example, the underlying
* connection may be closed by the SAN target due to an inactivity
* timeout, or the SAN target may return pointless "error" messages
* such as "SCSI power-on occurred".
*/
#define SAN_DEFAULT_RETRIES 10
/**
* Delay between reopening attempts
*
* Some SAN targets will always accept connections instantly and
* report a temporary unavailability by e.g. failing the TEST UNIT
* READY command. Avoid bombarding such targets by introducing a
* small delay between attempts.
*/
#define SAN_REOPEN_DELAY_SECS 5
/** List of SAN devices */
LIST_HEAD ( san_devices );
/** Number of times to retry commands */
static unsigned long san_retries = SAN_DEFAULT_RETRIES;
/**
* Find SAN device by drive number
*
* @v drive Drive number
* @ret sandev SAN device, or NULL
*/
struct san_device * sandev_find ( unsigned int drive ) {
struct san_device *sandev;
list_for_each_entry ( sandev, &san_devices, list ) {
if ( sandev->drive == drive )
return sandev;
}
return NULL;
}
/**
* Find next SAN device by drive number
*
* @v drive Minimum drive number
* @ret sandev SAN device, or NULL
*/
struct san_device * sandev_next ( unsigned int drive ) {
struct san_device *sandev;
list_for_each_entry ( sandev, &san_devices, list ) {
if ( sandev->drive >= drive )
return sandev;
}
return NULL;
}
/**
* Free SAN device
*
* @v refcnt Reference count
*/
static void sandev_free ( struct refcnt *refcnt ) {
struct san_device *sandev =
container_of ( refcnt, struct san_device, refcnt );
unsigned int i;
assert ( ! timer_running ( &sandev->timer ) );
assert ( ! sandev->active );
assert ( list_empty ( &sandev->opened ) );
for ( i = 0 ; i < sandev->paths ; i++ ) {
uri_put ( sandev->path[i].uri );
assert ( sandev->path[i].desc == NULL );
}
free ( sandev );
}
/**
* Close SAN device command
*
* @v sandev SAN device
* @v rc Reason for close
*/
static void sandev_command_close ( struct san_device *sandev, int rc ) {
/* Stop timer */
stop_timer ( &sandev->timer );
/* Restart interface */
intf_restart ( &sandev->command, rc );
/* Record command status */
sandev->command_rc = rc;
}
/**
* Record SAN device capacity
*
* @v sandev SAN device
* @v capacity SAN device capacity
*/
static void sandev_command_capacity ( struct san_device *sandev,
struct block_device_capacity *capacity ) {
/* Record raw capacity information */
memcpy ( &sandev->capacity, capacity, sizeof ( sandev->capacity ) );
}
/** SAN device command interface operations */
static struct interface_operation sandev_command_op[] = {
INTF_OP ( intf_close, struct san_device *, sandev_command_close ),
INTF_OP ( block_capacity, struct san_device *,
sandev_command_capacity ),
};
/** SAN device command interface descriptor */
static struct interface_descriptor sandev_command_desc =
INTF_DESC ( struct san_device, command, sandev_command_op );
/**
* Handle SAN device command timeout
*
* @v retry Retry timer
*/
static void sandev_command_expired ( struct retry_timer *timer,
int over __unused ) {
struct san_device *sandev =
container_of ( timer, struct san_device, timer );
sandev_command_close ( sandev, -ETIMEDOUT );
}
/**
* Open SAN path
*
* @v sanpath SAN path
* @ret rc Return status code
*/
static int sanpath_open ( struct san_path *sanpath ) {
struct san_device *sandev = sanpath->sandev;
int rc;
/* Sanity check */
list_check_contains_entry ( sanpath, &sandev->closed, list );
/* Open interface */
if ( ( rc = xfer_open_uri ( &sanpath->block, sanpath->uri ) ) != 0 ) {
DBGC ( sandev->drive, "SAN %#02x.%d could not (re)open URI: "
"%s\n", sandev->drive, sanpath->index, strerror ( rc ) );
return rc;
}
/* Update ACPI descriptor, if applicable */
if ( ! ( sandev->flags & SAN_NO_DESCRIBE ) ) {
if ( sanpath->desc )
acpi_del ( sanpath->desc );
sanpath->desc = acpi_describe ( &sanpath->block );
if ( sanpath->desc )
acpi_add ( sanpath->desc );
}
/* Start process */
process_add ( &sanpath->process );
/* Mark as opened */
list_del ( &sanpath->list );
list_add_tail ( &sanpath->list, &sandev->opened );
/* Record as in progress */
sanpath->path_rc = -EINPROGRESS;
return 0;
}
/**
* Close SAN path
*
* @v sanpath SAN path
* @v rc Reason for close
*/
static void sanpath_close ( struct san_path *sanpath, int rc ) {
struct san_device *sandev = sanpath->sandev;
/* Record status */
sanpath->path_rc = rc;
/* Mark as closed */
list_del ( &sanpath->list );
list_add_tail ( &sanpath->list, &sandev->closed );
/* Stop process */
process_del ( &sanpath->process );
/* Restart interfaces, avoiding potential loops */
if ( sanpath == sandev->active ) {
intfs_restart ( rc, &sandev->command, &sanpath->block, NULL );
sandev->active = NULL;
sandev_command_close ( sandev, rc );
} else {
intf_restart ( &sanpath->block, rc );
}
}
/**
* Handle closure of underlying block device interface
*
* @v sanpath SAN path
* @v rc Reason for close
*/
static void sanpath_block_close ( struct san_path *sanpath, int rc ) {
struct san_device *sandev = sanpath->sandev;
/* Any closure is an error from our point of view */
if ( rc == 0 )
rc = -ENOTCONN;
DBGC ( sandev->drive, "SAN %#02x.%d closed: %s\n",
sandev->drive, sanpath->index, strerror ( rc ) );
/* Close path */
sanpath_close ( sanpath, rc );
}
/**
* Check flow control window
*
* @v sanpath SAN path
*/
static size_t sanpath_block_window ( struct san_path *sanpath __unused ) {
/* We are never ready to receive data via this interface.
* This prevents objects that support both block and stream
* interfaces from attempting to send us stream data.
*/
return 0;
}
/**
* SAN path process
*
* @v sanpath SAN path
*/
static void sanpath_step ( struct san_path *sanpath ) {
struct san_device *sandev = sanpath->sandev;
/* Ignore if we are already the active device */
if ( sanpath == sandev->active )
return;
/* Wait until path has become available */
if ( ! xfer_window ( &sanpath->block ) )
return;
/* Record status */
sanpath->path_rc = 0;
/* Mark as active path or close as applicable */
if ( ! sandev->active ) {
DBGC ( sandev->drive, "SAN %#02x.%d is active\n",
sandev->drive, sanpath->index );
sandev->active = sanpath;
} else {
DBGC ( sandev->drive, "SAN %#02x.%d is available\n",
sandev->drive, sanpath->index );
sanpath_close ( sanpath, 0 );
}
}
/** SAN path block interface operations */
static struct interface_operation sanpath_block_op[] = {
INTF_OP ( intf_close, struct san_path *, sanpath_block_close ),
INTF_OP ( xfer_window, struct san_path *, sanpath_block_window ),
INTF_OP ( xfer_window_changed, struct san_path *, sanpath_step ),
};
/** SAN path block interface descriptor */
static struct interface_descriptor sanpath_block_desc =
INTF_DESC ( struct san_path, block, sanpath_block_op );
/** SAN path process descriptor */
static struct process_descriptor sanpath_process_desc =
PROC_DESC_ONCE ( struct san_path, process, sanpath_step );
/**
* Restart SAN device interface
*
* @v sandev SAN device
* @v rc Reason for restart
*/
static void sandev_restart ( struct san_device *sandev, int rc ) {
struct san_path *sanpath;
/* Restart all block device interfaces */
while ( ( sanpath = list_first_entry ( &sandev->opened,
struct san_path, list ) ) ) {
sanpath_close ( sanpath, rc );
}
/* Clear active path */
sandev->active = NULL;
/* Close any outstanding command */
sandev_command_close ( sandev, rc );
}
/**
* (Re)open SAN device
*
* @v sandev SAN device
* @ret rc Return status code
*
* This function will block until the device is available.
*/
int sandev_reopen ( struct san_device *sandev ) {
struct san_path *sanpath;
int rc;
/* Unquiesce system */
unquiesce();
/* Close any outstanding command and restart interfaces */
sandev_restart ( sandev, -ECONNRESET );
assert ( sandev->active == NULL );
assert ( list_empty ( &sandev->opened ) );
/* Open all paths */
while ( ( sanpath = list_first_entry ( &sandev->closed,
struct san_path, list ) ) ) {
if ( ( rc = sanpath_open ( sanpath ) ) != 0 )
goto err_open;
}
/* Wait for any device to become available, or for all devices
* to fail.
*/
while ( sandev->active == NULL ) {
step();
if ( list_empty ( &sandev->opened ) ) {
/* Get status of the first device to be
* closed. Do this on the basis that earlier
* errors (e.g. "invalid IQN") are probably
* more interesting than later errors
* (e.g. "TCP timeout").
*/
rc = -ENODEV;
list_for_each_entry ( sanpath, &sandev->closed, list ) {
rc = sanpath->path_rc;
break;
}
DBGC ( sandev->drive, "SAN %#02x never became "
"available: %s\n", sandev->drive,
strerror ( rc ) );
goto err_none;
}
}
assert ( ! list_empty ( &sandev->opened ) );
return 0;
err_none:
err_open:
sandev_restart ( sandev, rc );
return rc;
}
/** SAN device read/write command parameters */
struct san_command_rw_params {
/** SAN device read/write operation */
int ( * block_rw ) ( struct interface *control, struct interface *data,
uint64_t lba, unsigned int count,
userptr_t buffer, size_t len );
/** Data buffer */
userptr_t buffer;
/** Starting LBA */
uint64_t lba;
/** Block count */
unsigned int count;
};
/** SAN device command parameters */
union san_command_params {
/** Read/write command parameters */
struct san_command_rw_params rw;
};
/**
* Initiate SAN device read/write command
*
* @v sandev SAN device
* @v params Command parameters
* @ret rc Return status code
*/
static int sandev_command_rw ( struct san_device *sandev,
const union san_command_params *params ) {
struct san_path *sanpath = sandev->active;
size_t len = ( params->rw.count * sandev->capacity.blksize );
int rc;
/* Sanity check */
assert ( sanpath != NULL );
/* Initiate read/write command */
if ( ( rc = params->rw.block_rw ( &sanpath->block, &sandev->command,
params->rw.lba, params->rw.count,
params->rw.buffer, len ) ) != 0 ) {
DBGC ( sandev->drive, "SAN %#02x.%d could not initiate "
"read/write: %s\n", sandev->drive, sanpath->index,
strerror ( rc ) );
return rc;
}
return 0;
}
/**
* Initiate SAN device read capacity command
*
* @v sandev SAN device
* @v params Command parameters
* @ret rc Return status code
*/
static int
sandev_command_read_capacity ( struct san_device *sandev,
const union san_command_params *params __unused){
struct san_path *sanpath = sandev->active;
int rc;
/* Sanity check */
assert ( sanpath != NULL );
/* Initiate read capacity command */
if ( ( rc = block_read_capacity ( &sanpath->block,
&sandev->command ) ) != 0 ) {
DBGC ( sandev->drive, "SAN %#02x.%d could not initiate read "
"capacity: %s\n", sandev->drive, sanpath->index,
strerror ( rc ) );
return rc;
}
return 0;
}
/**
* Execute a single SAN device command and wait for completion
*
* @v sandev SAN device
* @v command Command
* @v params Command parameters (if required)
* @ret rc Return status code
*/
static int
sandev_command ( struct san_device *sandev,
int ( * command ) ( struct san_device *sandev,
const union san_command_params *params ),
const union san_command_params *params ) {
unsigned int retries = 0;
int rc;
/* Sanity check */
assert ( ! timer_running ( &sandev->timer ) );
/* Unquiesce system */
unquiesce();
/* (Re)try command */
do {
/* Reopen block device if applicable */
if ( sandev_needs_reopen ( sandev ) &&
( ( rc = sandev_reopen ( sandev ) ) != 0 ) ) {
/* Delay reopening attempts */
sleep_fixed ( SAN_REOPEN_DELAY_SECS );
/* Retry opening indefinitely for multipath devices */
if ( sandev->paths <= 1 )
retries++;
continue;
}
/* Initiate command */
if ( ( rc = command ( sandev, params ) ) != 0 ) {
retries++;
continue;
}
/* Start expiry timer */
start_timer_fixed ( &sandev->timer, SAN_COMMAND_TIMEOUT );
/* Wait for command to complete */
while ( timer_running ( &sandev->timer ) )
step();
/* Check command status */
if ( ( rc = sandev->command_rc ) != 0 ) {
retries++;
continue;
}
return 0;
} while ( retries <= san_retries );
/* Sanity check */
assert ( ! timer_running ( &sandev->timer ) );
return rc;
}
/**
* Reset SAN device
*
* @v sandev SAN device
* @ret rc Return status code
*/
int sandev_reset ( struct san_device *sandev ) {
int rc;
DBGC ( sandev->drive, "SAN %#02x reset\n", sandev->drive );
/* Close and reopen underlying block device */
if ( ( rc = sandev_reopen ( sandev ) ) != 0 )
return rc;
return 0;
}
/**
* Read from or write to SAN device
*
* @v sandev SAN device
* @v lba Starting logical block address
* @v count Number of logical blocks
* @v buffer Data buffer
* @v block_rw Block read/write method
* @ret rc Return status code
*/
static int sandev_rw ( struct san_device *sandev, uint64_t lba,
unsigned int count, userptr_t buffer,
int ( * block_rw ) ( struct interface *control,
struct interface *data,
uint64_t lba, unsigned int count,
userptr_t buffer, size_t len ) ) {
union san_command_params params;
unsigned int remaining;
size_t frag_len;
int rc;
/* Initialise command parameters */
params.rw.block_rw = block_rw;
params.rw.buffer = buffer;
params.rw.lba = ( lba << sandev->blksize_shift );
params.rw.count = sandev->capacity.max_count;
remaining = ( count << sandev->blksize_shift );
/* Read/write fragments */
while ( remaining ) {
/* Determine fragment length */
if ( params.rw.count > remaining )
params.rw.count = remaining;
/* Execute command */
if ( ( rc = sandev_command ( sandev, sandev_command_rw,
&params ) ) != 0 )
return rc;
/* Move to next fragment */
frag_len = ( sandev->capacity.blksize * params.rw.count );
params.rw.buffer = userptr_add ( params.rw.buffer, frag_len );
params.rw.lba += params.rw.count;
remaining -= params.rw.count;
}
return 0;
}
/**
* Read from SAN device
*
* @v sandev SAN device
* @v lba Starting logical block address
* @v count Number of logical blocks
* @v buffer Data buffer
* @ret rc Return status code
*/
int sandev_read ( struct san_device *sandev, uint64_t lba,
unsigned int count, userptr_t buffer ) {
int rc;
/* Read from device */
if ( ( rc = sandev_rw ( sandev, lba, count, buffer, block_read ) ) != 0 )
return rc;
return 0;
}
/**
* Write to SAN device
*
* @v sandev SAN device
* @v lba Starting logical block address
* @v count Number of logical blocks
* @v buffer Data buffer
* @ret rc Return status code
*/
int sandev_write ( struct san_device *sandev, uint64_t lba,
unsigned int count, userptr_t buffer ) {
int rc;
/* Write to device */
if ( ( rc = sandev_rw ( sandev, lba, count, buffer, block_write ) ) != 0 )
return rc;
/* Quiesce system. This is a heuristic designed to ensure
* that the system is quiesced before Windows starts up, since
* a Windows SAN boot will typically write a status flag to
* the disk as its last action before transferring control to
* the native drivers.
*/
quiesce();
return 0;
}
/**
* Describe SAN device
*
* @v sandev SAN device
* @ret rc Return status code
*
* Allow connections to progress until all existent path descriptors
* are complete.
*/
static int sandev_describe ( struct san_device *sandev ) {
struct san_path *sanpath;
struct acpi_descriptor *desc;
int rc;
/* Wait for all paths to be either described or closed */
while ( 1 ) {
/* Allow connections to progress */
step();
/* Fail if any closed path has an incomplete descriptor */
list_for_each_entry ( sanpath, &sandev->closed, list ) {
desc = sanpath->desc;
if ( ! desc )
continue;
if ( ( rc = desc->model->complete ( desc ) ) != 0 ) {
DBGC ( sandev->drive, "SAN %#02x.%d could not "
"be described: %s\n", sandev->drive,
sanpath->index, strerror ( rc ) );
return rc;
}
}
/* Succeed if no paths have an incomplete descriptor */
rc = 0;
list_for_each_entry ( sanpath, &sandev->opened, list ) {
desc = sanpath->desc;
if ( ! desc )
continue;
if ( ( rc = desc->model->complete ( desc ) ) != 0 )
break;
}
if ( rc == 0 )
return 0;
}
}
/**
* Remove SAN device descriptors
*
* @v sandev SAN device
*/
static void sandev_undescribe ( struct san_device *sandev ) {
struct san_path *sanpath;
unsigned int i;
/* Remove all ACPI descriptors */
for ( i = 0 ; i < sandev->paths ; i++ ) {
sanpath = &sandev->path[i];
if ( sanpath->desc ) {
acpi_del ( sanpath->desc );
sanpath->desc = NULL;
}
}
}
/**
* Configure SAN device as a CD-ROM, if applicable
*
* @v sandev SAN device
* @ret rc Return status code
*
* Both BIOS and UEFI require SAN devices to be accessed with a block
* size of 2048. While we could require the user to configure the
* block size appropriately, this is non-trivial and would impose a
* substantial learning effort on the user. Instead, we check for the
* presence of the ISO9660 primary volume descriptor and, if found,
* then we force a block size of 2048 and map read/write requests
* appropriately.
*/
static int sandev_parse_iso9660 ( struct san_device *sandev ) {
static const struct iso9660_primary_descriptor_fixed primary_check = {
.type = ISO9660_TYPE_PRIMARY,
.id = ISO9660_ID,
};
union {
struct iso9660_primary_descriptor primary;
char bytes[ISO9660_BLKSIZE];
} *scratch;
unsigned int blksize;
unsigned int blksize_shift;
unsigned int lba;
unsigned int count;
int rc;
/* Calculate required blocksize shift for potential CD-ROM access */
blksize = sandev->capacity.blksize;
blksize_shift = 0;
while ( blksize < ISO9660_BLKSIZE ) {
blksize <<= 1;
blksize_shift++;
}
if ( blksize > ISO9660_BLKSIZE ) {
/* Cannot be a CD-ROM. This is not an error. */
rc = 0;
goto invalid_blksize;
}
lba = ( ISO9660_PRIMARY_LBA << blksize_shift );
count = ( 1 << blksize_shift );
/* Allocate scratch area */
scratch = malloc ( ISO9660_BLKSIZE );
if ( ! scratch ) {
rc = -ENOMEM;
goto err_alloc;
}
/* Read primary volume descriptor */
if ( ( rc = sandev_read ( sandev, lba, count,
virt_to_user ( scratch ) ) ) != 0 ) {
DBGC ( sandev->drive, "SAN %#02x could not read ISO9660 "
"primary volume descriptor: %s\n",
sandev->drive, strerror ( rc ) );
goto err_rw;
}
/* Configure as CD-ROM if applicable */
if ( memcmp ( &scratch->primary.fixed, &primary_check,
sizeof ( primary_check ) ) == 0 ) {
DBGC ( sandev->drive, "SAN %#02x contains an ISO9660 "
"filesystem; treating as CD-ROM\n", sandev->drive );
sandev->blksize_shift = blksize_shift;
sandev->is_cdrom = 1;
}
err_rw:
free ( scratch );
err_alloc:
invalid_blksize:
return rc;
}
/**
* Allocate SAN device
*
* @v uris List of URIs
* @v count Number of URIs
* @v priv_size Size of private data
* @ret sandev SAN device, or NULL
*/
struct san_device * alloc_sandev ( struct uri **uris, unsigned int count,
size_t priv_size ) {
struct san_device *sandev;
struct san_path *sanpath;
size_t size;
unsigned int i;
/* Allocate and initialise structure */
size = ( sizeof ( *sandev ) + ( count * sizeof ( sandev->path[0] ) ) );
sandev = zalloc ( size + priv_size );
if ( ! sandev )
return NULL;
ref_init ( &sandev->refcnt, sandev_free );
intf_init ( &sandev->command, &sandev_command_desc, &sandev->refcnt );
timer_init ( &sandev->timer, sandev_command_expired, &sandev->refcnt );
sandev->priv = ( ( ( void * ) sandev ) + size );
sandev->paths = count;
INIT_LIST_HEAD ( &sandev->opened );
INIT_LIST_HEAD ( &sandev->closed );
for ( i = 0 ; i < count ; i++ ) {
sanpath = &sandev->path[i];
sanpath->sandev = sandev;
sanpath->index = i;
sanpath->uri = uri_get ( uris[i] );
list_add_tail ( &sanpath->list, &sandev->closed );
intf_init ( &sanpath->block, &sanpath_block_desc,
&sandev->refcnt );
process_init_stopped ( &sanpath->process, &sanpath_process_desc,
&sandev->refcnt );
sanpath->path_rc = -EINPROGRESS;
}
return sandev;
}
/**
* Register SAN device
*
* @v sandev SAN device
* @v drive Drive number
* @v flags Flags
* @ret rc Return status code
*/
int register_sandev ( struct san_device *sandev, unsigned int drive,
unsigned int flags ) {
struct san_device *before;
int rc;
/* Check that drive number is not in use */
if ( sandev_find ( drive ) != NULL ) {
DBGC ( sandev->drive, "SAN %#02x is already in use\n", drive );
rc = -EADDRINUSE;
goto err_in_use;
}
/* Record drive number and flags */
sandev->drive = drive;
sandev->flags = flags;
/* Check that device is capable of being opened (i.e. that all
* URIs are well-formed and that at least one path is
* working).
*/
if ( ( rc = sandev_reopen ( sandev ) ) != 0 )
goto err_reopen;
/* Describe device */
if ( ( rc = sandev_describe ( sandev ) ) != 0 )
goto err_describe;
/* Read device capacity */
if ( ( rc = sandev_command ( sandev, sandev_command_read_capacity,
NULL ) ) != 0 )
goto err_capacity;
/* Configure as a CD-ROM, if applicable */
if ( ( rc = sandev_parse_iso9660 ( sandev ) ) != 0 )
goto err_iso9660;
/* Add to list of SAN devices, in drive order */
for_each_sandev ( before ) {
if ( before->drive > sandev->drive )
break;
}
list_add_tail ( &sandev->list, &before->list );
DBGC ( sandev->drive, "SAN %#02x registered\n", sandev->drive );
return 0;
list_del ( &sandev->list );
err_iso9660:
err_capacity:
err_describe:
err_reopen:
sandev_restart ( sandev, rc );
sandev_undescribe ( sandev );
err_in_use:
return rc;
}
/**
* Unregister SAN device
*
* @v sandev SAN device
*/
void unregister_sandev ( struct san_device *sandev ) {
/* Sanity check */
assert ( ! timer_running ( &sandev->timer ) );
/* Remove from list of SAN devices */
list_del ( &sandev->list );
/* Shut down interfaces */
sandev_restart ( sandev, 0 );
/* Remove ACPI descriptors */
sandev_undescribe ( sandev );
DBGC ( sandev->drive, "SAN %#02x unregistered\n", sandev->drive );
}
/** The "san-drive" setting */
const struct setting san_drive_setting __setting ( SETTING_SANBOOT_EXTRA,
san-drive ) = {
.name = "san-drive",
.description = "SAN drive number",
.tag = DHCP_EB_SAN_DRIVE,
.type = &setting_type_uint8,
};
/**
* Get default SAN drive number
*
* @ret drive Default drive number
*/
unsigned int san_default_drive ( void ) {
unsigned long drive;
/* Use "san-drive" setting, if specified */
if ( fetch_uint_setting ( NULL, &san_drive_setting, &drive ) >= 0 )
return drive;
/* Otherwise, default to booting from first hard disk */
return SAN_DEFAULT_DRIVE;
}
/** The "san-retries" setting */
const struct setting san_retries_setting __setting ( SETTING_SANBOOT_EXTRA,
san-retries ) = {
.name = "san-retries",
.description = "SAN retry count",
.tag = DHCP_EB_SAN_RETRY,
.type = &setting_type_int8,
};
/**
* Apply SAN boot settings
*
* @ret rc Return status code
*/
static int sandev_apply ( void ) {
/* Apply "san-retries" setting */
if ( fetch_uint_setting ( NULL, &san_retries_setting,
&san_retries ) < 0 ) {
san_retries = SAN_DEFAULT_RETRIES;
}
return 0;
}
/** Settings applicator */
struct settings_applicator sandev_applicator __settings_applicator = {
.apply = sandev_apply,
};