sanboot.c File Reference

SAN booting. More...

#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>

Go to the source code of this file.

Data Structures
struct	san_command_rw_params
	SAN device read/write command parameters. More...
union	san_command_params
	SAN device command parameters. More...

Macros
#define	SAN_COMMAND_TIMEOUT   ( 15 * TICKS_PER_SEC )
	Timeout for block device commands (in ticks) More...
#define	SAN_DEFAULT_RETRIES   10
	Default number of times to retry commands. More...
#define	SAN_REOPEN_DELAY_SECS   5
	Delay between reopening attempts. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
	LIST_HEAD (san_devices)
	List of SAN devices. More...
struct san_device *	sandev_find (unsigned int drive)
	Find SAN device by drive number. More...
struct san_device *	sandev_next (unsigned int drive)
	Find next SAN device by drive number. More...
static void	sandev_free (struct refcnt *refcnt)
	Free SAN device. More...
static void	sandev_command_close (struct san_device *sandev, int rc)
	Close SAN device command. More...
static void	sandev_command_capacity (struct san_device *sandev, struct block_device_capacity *capacity)
	Record SAN device capacity. More...
static void	sandev_command_expired (struct retry_timer *timer, int over __unused)
	Handle SAN device command timeout. More...
static int	sanpath_open (struct san_path *sanpath)
	Open SAN path. More...
static void	sanpath_close (struct san_path *sanpath, int rc)
	Close SAN path. More...
static void	sanpath_block_close (struct san_path *sanpath, int rc)
	Handle closure of underlying block device interface. More...
static size_t	sanpath_block_window (struct san_path *sanpath __unused)
	Check flow control window. More...
static void	sanpath_step (struct san_path *sanpath)
	SAN path process. More...
static void	sandev_restart (struct san_device *sandev, int rc)
	Restart SAN device interface. More...
int	sandev_reopen (struct san_device *sandev)
	(Re)open SAN device More...
static int	sandev_command_rw (struct san_device *sandev, const union san_command_params *params)
	Initiate SAN device read/write command. More...
static int	sandev_command_read_capacity (struct san_device *sandev, const union san_command_params *params __unused)
	Initiate SAN device read capacity command. More...
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)
	Execute a single SAN device command and wait for completion. More...
int	sandev_reset (struct san_device *sandev)
	Reset SAN device. More...
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))
	Read from or write to SAN device. More...
int	sandev_read (struct san_device *sandev, uint64_t lba, unsigned int count, userptr_t buffer)
	Read from SAN device. More...
int	sandev_write (struct san_device *sandev, uint64_t lba, unsigned int count, userptr_t buffer)
	Write to SAN device. More...
static int	sandev_describe (struct san_device *sandev)
	Describe SAN device. More...
static void	sandev_undescribe (struct san_device *sandev)
	Remove SAN device descriptors. More...
static int	sandev_parse_iso9660 (struct san_device *sandev)
	Configure SAN device as a CD-ROM, if applicable. More...
struct san_device *	alloc_sandev (struct uri **uris, unsigned int count, size_t priv_size)
	Allocate SAN device. More...
int	register_sandev (struct san_device *sandev, unsigned int drive, unsigned int flags)
	Register SAN device. More...
void	unregister_sandev (struct san_device *sandev)
	Unregister SAN device. More...
const struct setting san_drive_setting	__setting (SETTING_SANBOOT_EXTRA, san-drive)
	The "san-drive" setting. More...
unsigned int	san_default_drive (void)
	Get default SAN drive number. More...
static int	sandev_apply (void)
	Apply SAN boot settings. More...

Variables
static unsigned long	san_retries = SAN_DEFAULT_RETRIES
	Number of times to retry commands. More...
static struct interface_operation	sandev_command_op []
	SAN device command interface operations. More...
static struct interface_descriptor	sandev_command_desc
	SAN device command interface descriptor. More...
static struct interface_operation	sanpath_block_op []
	SAN path block interface operations. More...
static struct interface_descriptor	sanpath_block_desc
	SAN path block interface descriptor. More...
static struct process_descriptor	sanpath_process_desc
	SAN path process descriptor. More...
struct settings_applicator sandev_applicator	__settings_applicator
	Settings applicator. More...

Detailed Description

SAN booting.

Definition in file sanboot.c.

Macro Definition Documentation

SAN_COMMAND_TIMEOUT

#define SAN_COMMAND_TIMEOUT   ( 15 * TICKS_PER_SEC )

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.

Definition at line 56 of file sanboot.c.

SAN_DEFAULT_RETRIES

#define SAN_DEFAULT_RETRIES   10

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".

Definition at line 66 of file sanboot.c.

SAN_REOPEN_DELAY_SECS

#define SAN_REOPEN_DELAY_SECS   5

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.

Definition at line 76 of file sanboot.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

LIST_HEAD()

LIST_HEAD

(

san_devices

)

List of SAN devices.

sandev_find()

struct san_device* sandev_find

(

unsigned int

drive

)

Find SAN device by drive number.

Parameters

drive

Drive number

Return values

sandev

SAN device, or NULL

Definition at line 90 of file sanboot.c.

                                                       {
        struct san_device *sandev;

        list_for_each_entry ( sandev, &san_devices, list ) {
                if ( sandev->drive == drive )
                        return sandev;
        }
        return NULL;
}

References drive, san_device::drive, san_device::list, list_for_each_entry, NULL, and san_devices.

Referenced by dummy_san_unhook(), efi_block_unhook(), int13_unhook(), and register_sandev().

sandev_next()

struct san_device* sandev_next

(

unsigned int

drive

)

Find next SAN device by drive number.

Parameters

drive

Minimum drive number

Return values

sandev

SAN device, or NULL

Definition at line 106 of file sanboot.c.

                                                       {
        struct san_device *sandev;

        list_for_each_entry ( sandev, &san_devices, list ) {
                if ( sandev->drive >= drive )
                        return sandev;
        }
        return NULL;
}

References drive, san_device::drive, san_device::list, list_for_each_entry, NULL, and san_devices.

Referenced by efi_block_boot().

sandev_free()

static void sandev_free ( struct refcnt *  refcnt )

static

Free SAN device.

Parameters

refcnt

Reference count

Definition at line 121 of file sanboot.c.

                                                  {
        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 );
}

References san_device::active, assert(), container_of, san_path::desc, free, list_empty, NULL, san_device::opened, san_device::path, san_device::paths, san_device::timer, san_path::uri, and uri_put().

Referenced by alloc_sandev().

sandev_command_close()

static void sandev_command_close ( struct san_device *  sandev, int  rc  )

static

Close SAN device command.

Parameters

sandev	SAN device
rc	Reason for close

Definition at line 142 of file sanboot.c.

                                                                       {

        /* Stop timer */
        stop_timer ( &sandev->timer );

        /* Restart interface */
        intf_restart ( &sandev->command, rc );

        /* Record command status */
        sandev->command_rc = rc;
}

References san_device::command, san_device::command_rc, intf_restart(), rc, stop_timer(), and san_device::timer.

Referenced by sandev_command_expired(), sandev_restart(), and sanpath_close().

sandev_command_capacity()

static void sandev_command_capacity ( struct san_device *  sandev, struct block_device_capacity *  capacity  )

static

Record SAN device capacity.

Parameters

sandev	SAN device
capacity	SAN device capacity

Definition at line 160 of file sanboot.c.

                                                                               {

        /* Record raw capacity information */
        memcpy ( &sandev->capacity, capacity, sizeof ( sandev->capacity ) );
}

References san_device::capacity, and memcpy().

sandev_command_expired()

static void sandev_command_expired ( struct retry_timer *  timer, int over  __unused  )

static

Handle SAN device command timeout.

Parameters

retry

Retry timer

Definition at line 183 of file sanboot.c.

                                                         {
        struct san_device *sandev =
                container_of ( timer, struct san_device, timer );

        sandev_command_close ( sandev, -ETIMEDOUT );
}

References container_of, ETIMEDOUT, and sandev_command_close().

Referenced by alloc_sandev().

sanpath_open()

static int sanpath_open ( struct san_path *  sanpath )

static

Open SAN path.

Parameters

sanpath

SAN path

Return values

rc	Return status code

Definition at line 197 of file sanboot.c.

                                                     {
        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;
}

References acpi_add(), acpi_del(), acpi_describe(), san_path::block, san_device::closed, DBGC, san_path::desc, san_device::drive, EINPROGRESS, san_device::flags, san_path::index, san_path::list, san_device::list, list_add_tail, list_check_contains_entry, list_del, san_device::opened, san_path::path_rc, san_path::process, process_add(), rc, SAN_NO_DESCRIBE, san_path::sandev, strerror(), san_path::uri, and xfer_open_uri().

Referenced by sandev_reopen().

sanpath_close()

static void sanpath_close ( struct san_path *  sanpath, int  rc  )

static

Close SAN path.

Parameters

sanpath	SAN path
rc	Reason for close

Definition at line 239 of file sanboot.c.

                                                               {
        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 );
        }
}

References san_device::active, san_path::block, san_device::closed, san_device::command, intf_restart(), intfs_restart(), san_path::list, list_add_tail, list_del, NULL, san_path::path_rc, san_path::process, process_del(), rc, san_path::sandev, and sandev_command_close().

Referenced by sandev_restart(), sanpath_block_close(), and sanpath_step().

sanpath_block_close()

static void sanpath_block_close ( struct san_path *  sanpath, int  rc  )

static

Handle closure of underlying block device interface.

Parameters

sanpath	SAN path
rc	Reason for close

Definition at line 268 of file sanboot.c.

                                                                     {
        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 );
}

References DBGC, san_device::drive, ENOTCONN, san_path::index, rc, san_path::sandev, sanpath_close(), and strerror().

sanpath_block_window()

static size_t sanpath_block_window ( struct san_path *sanpath  __unused )

static

Check flow control window.

Parameters

sanpath

SAN path

Definition at line 286 of file sanboot.c.

                                                                         {

        /* 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;
}

sanpath_step()

static void sanpath_step ( struct san_path *  sanpath )

static

SAN path process.

Parameters

sanpath

SAN path

Definition at line 300 of file sanboot.c.

                                                      {
        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 );
        }
}

References san_device::active, san_path::block, DBGC, san_device::drive, san_path::index, san_path::path_rc, san_path::sandev, sanpath_close(), and xfer_window().

sandev_restart()

static void sandev_restart ( struct san_device *  sandev, int  rc  )

static

Restart SAN device interface.

Parameters

sandev	SAN device
rc	Reason for restart

Definition at line 347 of file sanboot.c.

                                                                 {
        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 );
}

References san_device::active, san_path::list, list_first_entry, NULL, san_device::opened, rc, san_path::sandev, sandev_command_close(), and sanpath_close().

Referenced by register_sandev(), sandev_reopen(), and unregister_sandev().

sandev_reopen()

int sandev_reopen

(

struct san_device *

sandev

)

(Re)open SAN device

Parameters

sandev

SAN device

Return values

rc	Return status code

This function will block until the device is available.

Definition at line 371 of file sanboot.c.

                                                {
        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;
}

References san_device::active, assert(), san_device::closed, DBGC, san_device::drive, ECONNRESET, ENODEV, san_path::list, list_empty, list_first_entry, list_for_each_entry, NULL, san_device::opened, san_path::path_rc, rc, san_path::sandev, sandev_restart(), sanpath_open(), step(), strerror(), and unquiesce().

Referenced by int13_device_path_info(), register_sandev(), sandev_command(), and sandev_reset().

sandev_command_rw()

static int sandev_command_rw ( struct san_device *  sandev, const union san_command_params *  params  )

static

Initiate SAN device read/write command.

Parameters

sandev	SAN device
params	Command parameters

Return values

rc	Return status code

Definition at line 450 of file sanboot.c.

                                                                        {
        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;
}

References san_device::active, assert(), block_device_capacity::blksize, san_path::block, san_command_rw_params::block_rw, san_command_rw_params::buffer, san_device::capacity, san_device::command, san_command_rw_params::count, DBGC, san_device::drive, san_path::index, san_command_rw_params::lba, len, NULL, rc, san_command_params::rw, san_path::sandev, and strerror().

Referenced by sandev_rw().

sandev_command_read_capacity()

static int sandev_command_read_capacity ( struct san_device *  sandev, const union san_command_params *params  __unused  )

static

Initiate SAN device read capacity command.

Parameters

sandev	SAN device
params	Command parameters

Return values

rc	Return status code

Definition at line 480 of file sanboot.c.

                                                                               {
        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;
}

References san_device::active, assert(), san_path::block, block_read_capacity(), san_device::command, DBGC, san_device::drive, san_path::index, NULL, rc, san_path::sandev, and strerror().

Referenced by register_sandev().

sandev_command()

static int sandev_command ( struct san_device *  sandev, int(*)(struct san_device *sandev, const union san_command_params *params)  command, const union san_command_params *  params  )

static

Execute a single SAN device command and wait for completion.

Parameters

sandev	SAN device
command	Command
params	Command parameters (if required)

Return values

rc	Return status code

Definition at line 509 of file sanboot.c.

                                                          {
        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;
}

References assert(), san_device::command_rc, san_device::paths, rc, SAN_COMMAND_TIMEOUT, SAN_REOPEN_DELAY_SECS, san_retries, san_path::sandev, sandev_needs_reopen(), sandev_reopen(), sleep_fixed(), start_timer_fixed(), step(), san_device::timer, and unquiesce().

Referenced by register_sandev(), and sandev_rw().

sandev_reset()

int sandev_reset

(

struct san_device *

sandev

)

Reset SAN device.

Parameters

sandev

SAN device

Return values

rc	Return status code

Definition at line 574 of file sanboot.c.

                                               {
        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;
}

References DBGC, san_device::drive, rc, san_path::sandev, and sandev_reopen().

Referenced by efi_block_io_reset(), and int13_reset().

sandev_rw()

static int sandev_rw ( struct san_device *  sandev, uint64_t  lba, unsigned int  count, userptr_t  buffer, int(*)(struct interface *control, struct interface *data, uint64_t lba, unsigned int count, userptr_t buffer, size_t len)  block_rw  )

static

Read from or write to SAN device.

Parameters

sandev	SAN device
lba	Starting logical block address
count	Number of logical blocks
buffer	Data buffer
block_rw	Block read/write method

Return values

rc	Return status code

Definition at line 596 of file sanboot.c.

                                                                             {
        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;
}

References block_device_capacity::blksize, san_device::blksize_shift, san_command_rw_params::block_rw, buffer, san_command_rw_params::buffer, san_device::capacity, count, san_command_rw_params::count, lba, san_command_rw_params::lba, block_device_capacity::max_count, rc, san_command_params::rw, sandev_command(), sandev_command_rw(), and userptr_add().

Referenced by efi_block_rw(), int13_extended_rw(), int13_rw_sectors(), sandev_read(), and sandev_write().

sandev_read()

int sandev_read	(	struct san_device *	sandev,
		uint64_t	lba,
		unsigned int	count,
		userptr_t	buffer
	)

Read from SAN device.

Parameters

sandev	SAN device
lba	Starting logical block address
count	Number of logical blocks
buffer	Data buffer

Return values

rc	Return status code

Definition at line 645 of file sanboot.c.

                                                         {
        int rc;

        /* Read from device */
        if ( ( rc = sandev_rw ( sandev, lba, count, buffer, block_read ) ) != 0 )
                return rc;

        return 0;
}

References block_read(), buffer, count, lba, rc, and sandev_rw().

Referenced by efi_block_io_read(), int13_cdrom_read_boot_catalog(), int13_extended_read(), int13_guess_geometry_hdd(), int13_parse_eltorito(), int13_read_sectors(), and sandev_parse_iso9660().

sandev_write()

int sandev_write	(	struct san_device *	sandev,
		uint64_t	lba,
		unsigned int	count,
		userptr_t	buffer
	)

Write to SAN device.

Parameters

sandev	SAN device
lba	Starting logical block address
count	Number of logical blocks
buffer	Data buffer

Return values

rc	Return status code

Definition at line 665 of file sanboot.c.

                                                          {
        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;
}

References block_write(), buffer, count, lba, quiesce(), rc, and sandev_rw().

Referenced by efi_block_io_write(), int13_extended_write(), and int13_write_sectors().

sandev_describe()

static int sandev_describe ( struct san_device *  sandev )

static

Describe SAN device.

Parameters

sandev

SAN device

Return values

rc	Return status code

Allow connections to progress until all existent path descriptors are complete.

Definition at line 693 of file sanboot.c.

                                                         {
        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;
        }
}

References san_device::closed, DBGC, desc, san_path::desc, san_device::drive, san_path::index, acpi_descriptor::list, list_for_each_entry, san_device::opened, rc, step(), and strerror().

Referenced by register_sandev().

sandev_undescribe()

static void sandev_undescribe ( struct san_device *  sandev )

static

Remove SAN device descriptors.

Parameters

sandev

SAN device

Definition at line 736 of file sanboot.c.

                                                            {
        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;
                }
        }
}

References acpi_del(), san_path::desc, NULL, san_device::path, san_device::paths, and san_path::sandev.

Referenced by register_sandev(), and unregister_sandev().

sandev_parse_iso9660()

static int sandev_parse_iso9660 ( struct san_device *  sandev )

static

Configure SAN device as a CD-ROM, if applicable.

Parameters

sandev

SAN device

Return values

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.

Definition at line 764 of file sanboot.c.

                                                              {
        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;
}

References block_device_capacity::blksize, blksize, san_device::blksize_shift, bytes, san_device::capacity, count, DBGC, san_device::drive, ENOMEM, free, san_device::is_cdrom, ISO9660_BLKSIZE, ISO9660_ID, ISO9660_PRIMARY_LBA, ISO9660_TYPE_PRIMARY, lba, malloc(), memcmp(), primary, rc, sandev_read(), strerror(), iso9660_primary_descriptor_fixed::type, and virt_to_user().

Referenced by register_sandev().

alloc_sandev()

struct san_device* alloc_sandev	(	struct uri **	uris,
		unsigned int	count,
		size_t	priv_size
	)

Allocate SAN device.

Parameters

uris	List of URIs
count	Number of URIs
priv_size	Size of private data

Return values

sandev

SAN device, or NULL

Definition at line 834 of file sanboot.c.

                                                      {
        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;
}

References san_path::block, san_device::closed, san_device::command, count, EINPROGRESS, san_path::index, INIT_LIST_HEAD, intf_init(), san_path::list, list_add_tail, NULL, san_device::opened, san_device::path, san_path::path_rc, san_device::paths, san_device::priv, san_path::process, process_init_stopped(), ref_init, san_device::refcnt, san_path::sandev, sandev_command_desc, sandev_command_expired(), sandev_free(), sanpath_block_desc, sanpath_process_desc, size, san_device::timer, san_path::uri, uri_get(), and zalloc().

Referenced by dummy_san_hook(), efi_block_hook(), and int13_hook().

register_sandev()

int register_sandev	(	struct san_device *	sandev,
		unsigned int	drive,
		unsigned int	flags
	)

Register SAN device.

Parameters

sandev	SAN device
drive	Drive number
flags	Flags

Return values

rc	Return status code

Definition at line 877 of file sanboot.c.

                                           {
        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;
}

References before, DBGC, drive, san_device::drive, EADDRINUSE, flags, san_device::flags, for_each_sandev, san_device::list, list_add_tail, list_del, NULL, rc, sandev_command(), sandev_command_read_capacity(), sandev_describe(), sandev_find(), sandev_parse_iso9660(), sandev_reopen(), sandev_restart(), and sandev_undescribe().

Referenced by dummy_san_hook(), efi_block_hook(), and int13_hook().

unregister_sandev()

void unregister_sandev

(

struct san_device *

sandev

)

Unregister SAN device.

Parameters

sandev

SAN device

Definition at line 939 of file sanboot.c.

                                                     {

        /* 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 );
}

References assert(), DBGC, san_device::drive, san_device::list, list_del, sandev_restart(), sandev_undescribe(), and san_device::timer.

Referenced by dummy_san_hook(), dummy_san_unhook(), efi_block_hook(), efi_block_unhook(), int13_hook(), and int13_unhook().

__setting()

const struct setting san_retries_setting __setting	(	SETTING_SANBOOT_EXTRA	,
		san-	drive
	)

Initial value:

= {
        .name = "san-retries",
        .description = "SAN retry count",
        .tag = DHCP_EB_SAN_RETRY,
        .type = &setting_type_int8,
}

The "san-drive" setting.

The "san-retries" setting.

san_default_drive()

unsigned int san_default_drive

(

void

)

Get default SAN drive number.

Return values

drive

Default drive number

Definition at line 970 of file sanboot.c.

                                        {
        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;
}

References drive, fetch_uint_setting(), NULL, and SAN_DEFAULT_DRIVE.

Referenced by netboot(), and sanboot_core_exec().

sandev_apply()

static int sandev_apply ( void  )

static

Apply SAN boot settings.

Return values

rc	Return status code

Definition at line 995 of file sanboot.c.

                                 {

        /* Apply "san-retries" setting */
        if ( fetch_uint_setting ( NULL, &san_retries_setting,
                                  &san_retries ) < 0 ) {
                san_retries = SAN_DEFAULT_RETRIES;
        }

        return 0;
}

References fetch_uint_setting(), NULL, SAN_DEFAULT_RETRIES, and san_retries.

Variable Documentation

san_retries

unsigned long san_retries = SAN_DEFAULT_RETRIES

static

Number of times to retry commands.

Definition at line 82 of file sanboot.c.

Referenced by sandev_apply(), and sandev_command().

sandev_command_op

struct interface_operation sandev_command_op[]

static

Initial value:

= {
        INTF_OP ( intf_close, struct san_device *, sandev_command_close ),
        INTF_OP ( block_capacity, struct san_device *,
                  sandev_command_capacity ),
}

SAN device command interface operations.

Definition at line 168 of file sanboot.c.

sandev_command_desc

struct interface_descriptor sandev_command_desc

static

Initial value:

=
        INTF_DESC ( struct san_device, command, sandev_command_op )

SAN device command interface descriptor.

Definition at line 175 of file sanboot.c.

Referenced by alloc_sandev().

sanpath_block_op

struct interface_operation sanpath_block_op[]

static

Initial value:

= {
        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 operations.

Definition at line 327 of file sanboot.c.

sanpath_block_desc

struct interface_descriptor sanpath_block_desc

static

Initial value:

=
        INTF_DESC ( struct san_path, block, sanpath_block_op )

SAN path block interface descriptor.

Definition at line 334 of file sanboot.c.

Referenced by alloc_sandev().

sanpath_process_desc

struct process_descriptor sanpath_process_desc

static

Initial value:

=
        PROC_DESC_ONCE ( struct san_path, process, sanpath_step )

SAN path process descriptor.

Definition at line 338 of file sanboot.c.

Referenced by alloc_sandev().

__settings_applicator

struct settings_applicator sandev_applicator __settings_applicator

Initial value:

= {
        .apply = sandev_apply,
}

Settings applicator.

Definition at line 1007 of file sanboot.c.