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0ac23deee2033dfd4fab16e20f0bcfcfa2ccb168
scst/scst/include/scst.h
Bart Van Assche 0ac23deee2 scst: Introduce tgt_dev.tgtt 
A later patch will free tgt_devs after an RCU grace period. Make it
safe to access the target template pointer after an RCU grace period.



git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@8474 d57e44dd-8a1f-0410-8b47-8ef2f437770f
2019-07-24 01:09:25 +00:00

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/*
* include/scst.h
*
* Copyright (C) 2004 - 2018 Vladislav Bolkhovitin <vst@vlnb.net>
* Copyright (C) 2004 - 2005 Leonid Stoljar
* Copyright (C) 2007 - 2018 Western Digital Corporation
* Copyright (C) 2010 - 2011 Bart Van Assche <bvanassche@acm.org>.
*
* Main SCSI target mid-level include file.
*
* 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, version 2
* of the License.
*
* 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.
*/
#ifndef __SCST_H
#define __SCST_H
/** See README for description of those conditional defines **/
/* #define CONFIG_SCST_DEBUG_TM */
/* #define CONFIG_SCST_TM_DBG_GO_OFFLINE */
/** See README for description of those conditional defines **/
#define CONFIG_SCST_DIF_INJECT_CORRUPTED_TAGS
/* #define CONFIG_SCST_FORWARD_MODE_PASS_THROUGH */
#define CONFIG_SCST_NO_TOTAL_MEM_CHECKS
#include <linux/types.h>
#ifndef INSIDE_KERNEL_TREE
#include <linux/version.h>
#endif
#include <linux/blkdev.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/cpumask.h>
#include <linux/dlm.h>
#include <asm/unaligned.h>
#if 0 /* Let's disable it for now to see if users will complain about it */
#define CONFIG_SCST_PER_DEVICE_CMD_COUNT_LIMIT
#endif
#if defined(RHEL_MAJOR) && RHEL_MAJOR -0 <= 5
#error RHEL 5 is no longer supported. Please upgrade to RHEL 6 or later.
#elif LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
#error The SCST sysfs interface is supported from kernel version 2.6.26 on. Please upgrade to a newer kernel version.
#endif
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi.h>
#ifdef INSIDE_KERNEL_TREE
#include <scst/backport.h>
#include <scst/scst_const.h>
#else
#include <build_mode.h>
#include <backport.h>
#include <scst_const.h>
#endif
#ifdef NOLOCKDEP_SUPPORTED
#define spin_lock_nolockdep(lock) \
do { \
current->nolockdep_call = 1; \
spin_lock(lock); \
current->nolockdep_call = 0; \
} while (0)
#define spin_unlock_nolockdep(lock) \
do { \
current->nolockdep_call = 1; \
spin_unlock(lock); \
current->nolockdep_call = 0; \
} while (0)
#define mutex_lock_nolockdep(lock) \
do { \
current->nolockdep_call = 1; \
mutex_lock(lock); \
current->nolockdep_call = 0; \
} while (0)
#define mutex_unlock_nolockdep(lock) \
do { \
current->nolockdep_call = 1; \
mutex_unlock(lock); \
current->nolockdep_call = 0; \
} while (0)
#define down_read_nolockdep(lock) \
do { \
current->nolockdep_call = 1; \
down_read(lock); \
current->nolockdep_call = 0; \
} while (0)
#define up_read_nolockdep(lock) \
do { \
current->nolockdep_call = 1; \
up_read(lock); \
current->nolockdep_call = 0; \
} while (0)
#define down_write_nolockdep(lock) \
do { \
current->nolockdep_call = 1; \
down_write(lock); \
current->nolockdep_call = 0; \
} while (0)
#define up_write_nolockdep(lock) \
do { \
current->nolockdep_call = 1; \
up_write(lock); \
current->nolockdep_call = 0; \
} while (0)
#else
#define spin_lock_nolockdep spin_lock
#define spin_unlock_nolockdep spin_unlock
#define mutex_lock_nolockdep mutex_lock
#define mutex_unlock_nolockdep mutex_unlock
#define down_read_nolockdep down_read
#define up_read_nolockdep up_read
#define down_write_nolockdep down_write
#define up_write_nolockdep up_write
#endif
#ifdef INSIDE_KERNEL_TREE
#include <scst/scst_sgv.h>
#else
#include "scst_sgv.h"
#endif
#define SCST_INTERFACE_VERSION \
SCST_VERSION_STRING SCST_INTF_VER SCST_CONST_VERSION
#define SCST_LOCAL_NAME "scst_local"
/*************************************************************
** States of command processing state machine. At first,
** "active" states, then - "passive" ones. This is to have
** more efficient generated code of the corresponding
** "switch" statements.
**
** !! Adding new states don't forget to update scst_cmd_state_name
** !! as well!
*************************************************************/
enum scst_cmd_state {
/** Active states **/
/* Dev handler's parse() is going to be called */
SCST_CMD_STATE_PARSE = 0,
/* Allocation of the cmd's data buffer */
SCST_CMD_STATE_PREPARE_SPACE,
/* Calling preprocessing_done() */
SCST_CMD_STATE_PREPROCESSING_DONE,
/* Target driver's rdy_to_xfer() is going to be called */
SCST_CMD_STATE_RDY_TO_XFER,
/* Target driver's pre_exec() is going to be called */
SCST_CMD_STATE_TGT_PRE_EXEC,
/*
* Cmd is going to be sent for execution. The first stage of it is
* order checking
*/
SCST_CMD_STATE_EXEC_CHECK_SN,
/* Internal post-exec checks */
SCST_CMD_STATE_PRE_DEV_DONE,
/* Internal MODE SELECT pages related checks */
SCST_CMD_STATE_MODE_SELECT_CHECKS,
/* Dev handler's dev_done() is going to be called */
SCST_CMD_STATE_DEV_DONE,
/* Checks before target driver's xmit_response() is called */
SCST_CMD_STATE_PRE_XMIT_RESP,
/* Checks 1 before target driver's xmit_response() is called */
SCST_CMD_STATE_PRE_XMIT_RESP1,
SCST_CMD_STATE_CSW2,
/* Checks 2 before target driver's xmit_response() is called */
SCST_CMD_STATE_PRE_XMIT_RESP2,
/* Target driver's xmit_response() is going to be called */
SCST_CMD_STATE_XMIT_RESP,
/* Cmd finished */
SCST_CMD_STATE_FINISHED,
/* Internal cmd finished */
SCST_CMD_STATE_FINISHED_INTERNAL,
/* An invalid command state */
SCST_CMD_STATE_LAST_ACTIVE,
/** Passive states **/
/* A cmd is created, but scst_cmd_init_done() not called */
SCST_CMD_STATE_INIT_WAIT,
/* LUN translation (cmd->tgt_dev assignment) */
SCST_CMD_STATE_INIT,
SCST_CMD_STATE_CSW1,
/* Waiting for scst_restart_cmd() */
SCST_CMD_STATE_PREPROCESSING_DONE_CALLED,
/* Waiting for data from the initiator (until scst_rx_data() called) */
SCST_CMD_STATE_DATA_WAIT,
/*
* Cmd is ready for exec (after check if its device is blocked or should
* be blocked)
*/
SCST_CMD_STATE_EXEC_CHECK_BLOCKING,
/* Cmd is being checked if it should be executed locally */
SCST_CMD_STATE_LOCAL_EXEC,
/* Cmd is ready for execution */
SCST_CMD_STATE_REAL_EXEC,
/* Waiting for CDB's execution finish */
SCST_CMD_STATE_EXEC_WAIT,
/* Waiting for response's transmission finish */
SCST_CMD_STATE_XMIT_WAIT,
};
enum {
SCST_CMD_STATE_COUNT = SCST_CMD_STATE_XMIT_WAIT + 1
};
/*************************************************************
* Can be returned instead of cmd's state by dev handlers'
* functions, if the command's state should be set by default
*************************************************************/
#define SCST_CMD_STATE_DEFAULT 500
/*************************************************************
* Can be returned instead of cmd's state by dev handlers'
* functions, if it is impossible to complete requested
* task in atomic context. The cmd will be restarted in thread
* context.
*************************************************************/
#define SCST_CMD_STATE_NEED_THREAD_CTX 1000
/*************************************************************
* Can be returned instead of cmd's state by dev handlers'
* parse function, if the cmd processing should be stopped
* for now. The cmd will be restarted by dev handlers itself.
*************************************************************/
#define SCST_CMD_STATE_STOP 1001
/*************************************************************
** States of mgmt command processing state machine
**
** !! Adding new states don't forget to update
** !! scst_mcmd_state_name as well!
*************************************************************/
enum {
/* LUN translation (mcmd->tgt_dev assignment) */
SCST_MCMD_STATE_INIT = 0,
/* Mgmt cmd is being processed */
SCST_MCMD_STATE_EXEC,
/* Waiting for affected commands done */
SCST_MCMD_STATE_WAITING_AFFECTED_CMDS_DONE,
/* Post actions when affected commands done */
SCST_MCMD_STATE_AFFECTED_CMDS_DONE,
/* Waiting for affected local commands finished */
SCST_MCMD_STATE_WAITING_AFFECTED_CMDS_FINISHED,
/* Target driver's task_mgmt_fn_done() is going to be called */
SCST_MCMD_STATE_DONE,
/* The mcmd finished */
SCST_MCMD_STATE_FINISHED,
};
/*************************************************************
** Constants for "atomic" parameter of SCST's functions
*************************************************************/
#define SCST_NON_ATOMIC 0
#define SCST_ATOMIC 1
/*************************************************************
** Values for pref_context parameter of scst_cmd_init_done(),
** scst_rx_data(), scst_restart_cmd(), scst_tgt_cmd_done()
** and scst_cmd_done()
*************************************************************/
enum scst_exec_context {
/*
* Direct cmd's processing (i.e. regular function calls in the current
* context) sleeping is not allowed
*/
SCST_CONTEXT_DIRECT_ATOMIC,
/*
* Direct cmd's processing (i.e. regular function calls in the current
* context), sleeping is allowed, no restrictions
*/
SCST_CONTEXT_DIRECT,
/* Tasklet or thread context required for cmd's processing */
SCST_CONTEXT_TASKLET,
/* Thread context required for cmd's processing */
SCST_CONTEXT_THREAD,
/*
* Context is the same as it was in previous call of the corresponding
* callback. For example, if dev handler's exec() does sync. data
* reading this value should be used for scst_cmd_done(). The same is
* true if scst_tgt_cmd_done() called directly from target driver's
* xmit_response(). Not allowed in scst_cmd_init_done() and
* scst_cmd_init_stage1_done().
*/
SCST_CONTEXT_SAME
};
/*************************************************************
** Values for status parameter of scst_rx_data()
*************************************************************/
/* Success */
#define SCST_RX_STATUS_SUCCESS 0
/*
* Data receiving finished with error, so set the sense and
* finish the command, including xmit_response() call
*/
#define SCST_RX_STATUS_ERROR 1
/*
* Data receiving finished with error and the sense is set,
* so finish the command, including xmit_response() call
*/
#define SCST_RX_STATUS_ERROR_SENSE_SET 2
/*
* Data receiving finished with fatal error, so finish the command,
* but don't call xmit_response()
*/
#define SCST_RX_STATUS_ERROR_FATAL 3
/*************************************************************
** Values for status parameter of scst_restart_cmd()
*************************************************************/
/* Success */
#define SCST_PREPROCESS_STATUS_SUCCESS 0
/*
* Command's processing finished with error, so set the sense and
* finish the command, including xmit_response() call
*/
#define SCST_PREPROCESS_STATUS_ERROR 1
/*
* Command's processing finished with error and the sense is set,
* so finish the command, including xmit_response() call
*/
#define SCST_PREPROCESS_STATUS_ERROR_SENSE_SET 2
/*
* Command's processing finished with fatal error, so finish the command,
* but don't call xmit_response()
*/
#define SCST_PREPROCESS_STATUS_ERROR_FATAL 3
/*************************************************************
** Values for AEN functions
*************************************************************/
/*
* SCSI Asynchronous Event. Parameter contains SCSI sense
* (Unit Attention). AENs generated only for 2 the following UAs:
* CAPACITY DATA HAS CHANGED and REPORTED LUNS DATA HAS CHANGED.
* Other UAs reported regularly as CHECK CONDITION status,
* because it doesn't look safe to report them using AENs, since
* reporting using AENs opens delivery race windows even in case of
* untagged commands.
*/
#define SCST_AEN_SCSI 0
/*
* Notifies that CPU affinity mask on the corresponding session changed
*/
#define SCST_AEN_CPU_MASK_CHANGED 1
/*************************************************************
** Allowed return/status codes for report_aen() callback and
** scst_set_aen_delivery_status() function
*************************************************************/
/* Success */
#define SCST_AEN_RES_SUCCESS 0
/* Not supported */
#define SCST_AEN_RES_NOT_SUPPORTED -1
/* Failure */
#define SCST_AEN_RES_FAILED -2
/*************************************************************
** Allowed return codes for xmit_response(), rdy_to_xfer()
*************************************************************/
/* Success */
#define SCST_TGT_RES_SUCCESS 0
/* Internal device queue is full, retry again later */
#define SCST_TGT_RES_QUEUE_FULL -1
/*
* It is impossible to complete requested task in atomic context.
* The cmd will be restarted in thread context.
*/
#define SCST_TGT_RES_NEED_THREAD_CTX -2
/*
* Fatal error, if returned by xmit_response() the cmd will
* be destroyed, if by any other function, xmit_response()
* will be called with READ or WRITE FAILED sense data
*/
#define SCST_TGT_RES_FATAL_ERROR -3
/*************************************************************
** Return codes for dev handler's exec()
*************************************************************/
enum scst_exec_res {
/*
* The device handler has finished executing the command or has
* started executing the command asynchronously.
*/
SCST_EXEC_COMPLETED = 0,
/* Pass through the command to the SCSI mid-level. */
SCST_EXEC_NOT_COMPLETED = 1,
};
/*************************************************************
** Session initialization phases
*************************************************************/
/* Set if session is being initialized */
#define SCST_SESS_IPH_INITING 0
/* Set if the session is successfully initialized */
#define SCST_SESS_IPH_SUCCESS 1
/* Set if the session initialization failed */
#define SCST_SESS_IPH_FAILED 2
/* Set if session is initialized and ready */
#define SCST_SESS_IPH_READY 3
/*************************************************************
** Session shutdown phases
*************************************************************/
/* Set if session is initialized and ready */
#define SCST_SESS_SPH_READY 0
/* Set if session is shutting down */
#define SCST_SESS_SPH_SHUTDOWN 1
/* Set if session is shutting down */
#define SCST_SESS_SPH_UNREG_DONE_CALLING 2
/*************************************************************
** Session's async (atomic) flags
*************************************************************/
/* Set if the sess's hw pending work is scheduled */
#define SCST_SESS_HW_PENDING_WORK_SCHEDULED 0
/*************************************************************
** Cmd's async (atomic) flags
*************************************************************/
/*
* Set if the cmd is aborted and should be unconditionally finished
* as soon as possible.
*
* !! Direct check of this bit must not be done anywhere outside of !!
* !! SCST core! Use the corresponding helper functions listed below !!
* !! for that! !!
*/
#define SCST_CMD_ABORTED 0
/* Set if the cmd is aborted by other initiator */
#define SCST_CMD_ABORTED_OTHER 1
/*
* Set if no response should be sent to the target about this cmd.
* Must be set together with SCST_CMD_ABORTED for better ACA processing
* in scst_pre_xmit_response2().
*/
#define SCST_CMD_NO_RESP 2
/* Set if the cmd is dead and can be destroyed at any time */
#define SCST_CMD_CAN_BE_DESTROYED 3
/*
* Set if the cmd's device has TAS flag set. Used only when aborted by
* other initiator.
*/
#define SCST_CMD_DEVICE_TAS 4
#ifdef CONFIG_SCST_EXTRACHECKS
/* Set if scst_inc_expected_sn() passed for this cmd */
#define SCST_CMD_INC_EXPECTED_SN_PASSED 10
#endif
/*************************************************************
** Tgt_dev's async. flags (tgt_dev_flags)
*************************************************************/
/* Set if tgt_dev has Unit Attention sense */
#define SCST_TGT_DEV_UA_PENDING 0
/* Cache of acg->acg_black_hole_type */
#define SCST_TGT_DEV_BLACK_HOLE 1
/* Cache of tgt->tgt_forwarding */
#define SCST_TGT_DEV_FORWARDING 5
/*************************************************************
** I/O grouping types. Changing them don't forget to change
** the corresponding *_STR values in scst_const.h!
*************************************************************/
/*
* All initiators with the same name connected to this group will have
* shared IO context, for each name own context. All initiators with
* different names will have own IO context.
*/
#define SCST_IO_GROUPING_AUTO 0
/* All initiators connected to this group will have shared IO context */
#define SCST_IO_GROUPING_THIS_GROUP_ONLY -1
/* Each initiator connected to this group will have own IO context */
#define SCST_IO_GROUPING_NEVER -2
/*************************************************************
** Valid_mask constants for scst_analyze_sense()
*************************************************************/
#define SCST_SENSE_KEY_VALID 1
#define SCST_SENSE_ASC_VALID 2
#define SCST_SENSE_ASCQ_VALID 4
#define SCST_SENSE_ASCx_VALID (SCST_SENSE_ASC_VALID | \
SCST_SENSE_ASCQ_VALID)
#define SCST_SENSE_ALL_VALID (SCST_SENSE_KEY_VALID | \
SCST_SENSE_ASC_VALID | \
SCST_SENSE_ASCQ_VALID)
/*************************************************************
** T10-PI (DIF) support
*************************************************************/
/*
* Defines where and how to deal with DIF tags. Can be OR'ed to get
* multilevel checks
*/
enum scst_dif_mode {
SCST_DIF_MODE_NONE = 0,
/* STRIP/INSERT/CHECK inside target HW */
SCST_DIF_MODE_TGT = 1,
/* SCST checking or creating tags on the fly */
SCST_DIF_MODE_SCST = 2,
/* Backend device checking tags */
SCST_DIF_MODE_DEV_CHECK = 4,
/* Backend device storing tags, creating them on writes, if needed */
SCST_DIF_MODE_DEV_STORE = 8,
};
#define SCST_DIF_MODE_DEV (SCST_DIF_MODE_DEV_CHECK|SCST_DIF_MODE_DEV_STORE)
#define SCST_DIF_MODE_TGT_STR "tgt"
#define SCST_DIF_MODE_SCST_STR "scst"
#define SCST_DIF_MODE_DEV_CHECK_STR "dev_check"
#define SCST_DIF_MODE_DEV_STORE_STR "dev_store"
/*
* T10-PI actions.
*
* Don't use masks and shifts directly! Use helper functions instead!
*/
enum scst_dif_actions {
SCST_DIF_ACTION_NONE = 0, /* do nothing */
#define SCST_DIF_CHECKS_SHIFT 0
/* OR'able tags to check */
SCST_DIF_CHECK_GUARD_TAG = 1,
SCST_DIF_CHECK_APP_TAG = 2,
SCST_DIF_CHECK_REF_TAG = 4,
#define SCST_DIF_CHECKS_MASK (SCST_DIF_CHECK_GUARD_TAG|SCST_DIF_CHECK_APP_TAG| \
SCST_DIF_CHECK_REF_TAG)
#define SCST_DIF_ACTION_SHIFT 4
/* How to handle PI */
SCST_DIF_ACTION_STRIP = (1 << SCST_DIF_ACTION_SHIFT), /* check then strip, if OK */
SCST_DIF_ACTION_INSERT = (2 << SCST_DIF_ACTION_SHIFT),
SCST_DIF_ACTION_PASS_CHECK = (3 << SCST_DIF_ACTION_SHIFT), /* check then pass, if OK */
SCST_DIF_ACTION_PASS = (4 << SCST_DIF_ACTION_SHIFT), /* just pass, no check */
#define SCST_DIF_ACTION_MASK (SCST_DIF_ACTION_STRIP|SCST_DIF_ACTION_INSERT| \
SCST_DIF_ACTION_PASS_CHECK|SCST_DIF_ACTION_PASS)
};
/* Shift for target driver DIF actions */
#define SCST_DIF_TGT_ACTION_SHIFT 0
/* Shift for SCST DIF actions */
#define SCST_DIF_SCST_ACTION_SHIFT (SCST_DIF_TGT_ACTION_SHIFT+4)
/* Shift for dev handler DIF actions */
#define SCST_DIF_DEV_ACTION_SHIFT (SCST_DIF_SCST_ACTION_SHIFT+4)
/* Returns DIF checks by stripping the action part from a */
static inline enum scst_dif_actions scst_get_dif_checks(enum scst_dif_actions a)
{
return a & SCST_DIF_CHECKS_MASK;
}
/* Sets the DIF checks part in a */
static inline void scst_set_dif_checks(enum scst_dif_actions *a,
enum scst_dif_actions checks)
{
checks &= ~SCST_DIF_CHECKS_MASK;
*a |= checks << SCST_DIF_CHECKS_SHIFT;
return;
}
/* Returns DIF action by stripping the checks part from a */
static inline enum scst_dif_actions scst_get_dif_action(enum scst_dif_actions a)
{
return a & SCST_DIF_ACTION_MASK;
}
/* Sets the DIF action part in a */
static inline void scst_set_dif_action(enum scst_dif_actions *a,
enum scst_dif_actions action)
{
action &= ~SCST_DIF_ACTION_MASK;
*a |= action;
return;
}
/* Returns TGT DIF actions from a, including checks */
static inline enum scst_dif_actions scst_get_tgt_dif_actions(enum scst_dif_actions a)
{
BUILD_BUG_ON(SCST_DIF_CHECKS_SHIFT != 0);
return ((a >> SCST_DIF_TGT_ACTION_SHIFT) & SCST_DIF_ACTION_MASK) |
(a & SCST_DIF_CHECKS_MASK);
}
/* Sets TGT DIF action in a. DIF checks in a are not affected by this function. */
static inline void scst_set_tgt_dif_action(enum scst_dif_actions *a,
enum scst_dif_actions tgt_a)
{
tgt_a &= SCST_DIF_ACTION_MASK;
*a |= tgt_a << SCST_DIF_TGT_ACTION_SHIFT;
return;
}
/* Returns SCST DIF actions from a, including checks */
static inline enum scst_dif_actions scst_get_scst_dif_actions(enum scst_dif_actions a)
{
BUILD_BUG_ON(SCST_DIF_CHECKS_SHIFT != 0);
return ((a >> SCST_DIF_SCST_ACTION_SHIFT) & SCST_DIF_ACTION_MASK) |
(a & SCST_DIF_CHECKS_MASK);
}
/* Sets SCST DIF action in a. DIF checks in a are not affected by this function. */
static inline void scst_set_scst_dif_action(enum scst_dif_actions *a,
enum scst_dif_actions scst_a)
{
scst_a &= SCST_DIF_ACTION_MASK;
*a |= scst_a << SCST_DIF_SCST_ACTION_SHIFT;
return;
}
/* Returns DEV DIF actions from a, including checks */
static inline enum scst_dif_actions scst_get_dev_dif_actions(enum scst_dif_actions a)
{
BUILD_BUG_ON(SCST_DIF_CHECKS_SHIFT != 0);
return ((a >> SCST_DIF_DEV_ACTION_SHIFT) & SCST_DIF_ACTION_MASK) |
(a & SCST_DIF_CHECKS_MASK);
}
/* Sets SCST DIF action in a. DIF checks in a are not affected by this function. */
static inline void scst_set_dev_dif_action(enum scst_dif_actions *a,
enum scst_dif_actions dev_a)
{
dev_a &= SCST_DIF_ACTION_MASK;
*a |= dev_a << SCST_DIF_DEV_ACTION_SHIFT;
return;
}
/*************************************************************
* TYPES
*************************************************************/
struct scst_tgt;
struct scst_session;
struct scst_cmd;
struct scst_mgmt_cmd;
struct scst_device;
struct scst_tgt_dev;
struct scst_dev_type;
struct scst_acg;
struct scst_acg_dev;
struct scst_acn;
struct scst_aen;
struct scst_ext_copy_seg_descr;
struct scst_opcode_descriptor;
/*
* SCST uses 64-bit numbers to represent LUN's internally. The value
* NO_SUCH_LUN is guaranteed to be different of every valid LUN.
*/
#define NO_SUCH_LUN ((uint64_t)-1)
/*
* SCST target template: defines target driver's parameters and callback
* functions.
*
* MUST HAVEs define functions that are expected to be defined in order to
* work. OPTIONAL says that there is a choice.
*/
struct scst_tgt_template {
/* public: */
/*
* If not NULL, points to 0-terminated array of integers listing all
* supported for T10-PI DIF-enabled devices block sizes. SCST will not
* allow to add DIF-enabled devices with another block sizes to this
* target driver's initiator groups.
*
* Can be overiden by scst_tgt_set_supported_dif_block_sizes()
*
* OPTIONAL
*/
const int *const supported_dif_block_sizes;
/*
* Preferred SCSI LUN addressing method.
*/
enum scst_lun_addr_method preferred_addr_method;
/*
* The maximum time in seconds cmd can stay inside the target
* hardware, i.e. after rdy_to_xfer() and xmit_response(), before
* on_hw_pending_cmd_timeout() will be called, if defined.
*
* In the current implementation a cmd will be aborted in time t
* max_hw_pending_time <= t < 2*max_hw_pending_time.
*/
int max_hw_pending_time;
/*
* SG tablesize allows to check whether scatter/gather can be used
* or not.
*/
int sg_tablesize;
/*
* True, if this target adapter uses unchecked DMA onto an ISA bus.
*/
unsigned unchecked_isa_dma:1;
/*
* True, if this target adapter can benefit from using SG-vector
* clustering (i.e. smaller number of segments).
*/
unsigned use_clustering:1;
/*
* True, if this target adapter doesn't support SG-vector clustering
*/
unsigned no_clustering:1;
/*
* True, if corresponding function supports execution in
* the atomic (non-sleeping) context
*/
unsigned xmit_response_atomic:1;
unsigned rdy_to_xfer_atomic:1;
/* True, if this target doesn't need "enabled" attribute */
unsigned enabled_attr_not_needed:1;
/*
* True, if this target adapter can call scst_cmd_init_done() from
* several threads at the same time.
*/
unsigned multithreaded_init_done:1;
/*
* True, if this target driver supports T10-PI (DIF), i.e. sending and
* receiving DIF PI tags. If false, SCST will not allow to add
* DIF-enabled devices to this target driver's initiator groups.
*
* Can be overridden per target by scst_tgt_set_dif_supported()
*/
unsigned dif_supported:1;
/*
* True, if this target driver supports T10-PI (DIF), i.e. INSERT/STRIPE
* mode, in hardware for type 1 protection. If false, SCST will not
* allow to add type 1 devices with TGT DIF mode to this target driver's
* initiator groups.
*
* Can be overridden per target by scst_tgt_set_hw_dif_type1_supported()
*/
unsigned hw_dif_type1_supported:1;
/*
* True, if this target driver supports T10-PI (DIF), i.e. INSERT/STRIPE
* mode, in hardware for type 2 protection. If false, SCST will not
* allow to add type 2 devices with TGT DIF mode to this target driver's
* initiator groups.
*
* Can be overridden per target by scst_tgt_set_hw_dif_type2_supported()
*/
unsigned hw_dif_type2_supported:1;
/*
* True, if this target driver supports T10-PI (DIF), i.e. INSERT/STRIPE
* mode, in hardware for type 3 protection. If false, SCST will not
* allow to add type 3 devices with TGT DIF mode to this target driver's
* initiator groups.
*
* Can be overridden per target by scst_tgt_set_hw_dif_type3_supported()
*/
unsigned hw_dif_type3_supported:1;
/*
* True, if this target driver supports IP checksum format of T10-PI
* (DIF) guard tags, i.e. hardware translation of guard tags between IP
* and CRC on SCST/target driver boundary for better performance,
* because IP checksums are much cheaper for CPU, than CRC.
*
* Can be overridden per target by scst_tgt_set_hw_dif_ip_supported()
*/
unsigned hw_dif_ip_supported:1;
/*
* True, if this target driver requires the same layout for both data
* and DIF tags SG vectors. Otherwise, for DIF tags minimally possible
* SG vector size will be allocated.
*
* Can be overridden per target by scst_tgt_set_hw_dif_same_sg_layout_required()
*/
unsigned hw_dif_same_sg_layout_required:1;
/*
* This function is equivalent to the SCSI
* queuecommand. The target should transmit the response
* buffer and the status in the scst_cmd struct.
* The expectation is that this executing this command is NON-BLOCKING.
* If it is blocking, consider to set threads_num to some none 0 number.
*
* After the response is actually transmitted, the target
* should call the scst_tgt_cmd_done() function of the
* mid-level, which will allow it to free up the command.
* Returns one of the SCST_TGT_RES_* constants.
*
* Pay attention to "atomic" attribute of the cmd, which can be get
* by scst_cmd_atomic(): it is true if the function called in the
* atomic (non-sleeping) context.
*
* MUST HAVE
*/
int (*xmit_response)(struct scst_cmd *cmd);
/*
* This function informs the driver that data
* buffer corresponding to the said command have now been
* allocated and it is OK to receive data for this command.
* This function is necessary because a SCSI target does not
* have any control over the commands it receives. Most lower
* level protocols have a corresponding function which informs
* the initiator that buffers have been allocated e.g., XFER_
* RDY in Fibre Channel. After the data is actually received
* the low-level driver needs to call scst_rx_data() in order to
* continue processing this command.
* Returns one of the SCST_TGT_RES_* constants.
*
* This command is expected to be NON-BLOCKING.
* If it is blocking, consider to set threads_num to some none 0 number.
*
* Pay attention to "atomic" attribute of the cmd, which can be get
* by scst_cmd_atomic(): it is true if the function called in the
* atomic (non-sleeping) context.
*
* OPTIONAL
*/
int (*rdy_to_xfer)(struct scst_cmd *cmd);
/*
* Called if cmd stays inside the target hardware, i.e. after
* rdy_to_xfer() and xmit_response(), more than max_hw_pending_time
* time. The target driver supposed to cleanup this command and
* resume cmd's processing.
*
* OPTIONAL
*/
void (*on_hw_pending_cmd_timeout)(struct scst_cmd *cmd);
/*
* Called to notify the driver that the command is about to be freed.
* Necessary, because for aborted commands xmit_response() could not
* be called. Could be called on IRQ context.
*
* This callback is called when the last reference to cmd is dropped,
* which can be much later after scst_tgt_cmd_done() called by the
* target driver, so it is not recommended that the target driver
* clean hardware or connection related cmd resources in this callback.
* It is recommended to clean them before calling scst_tgt_cmd_done()
* instead.
*
* OPTIONAL
*/
void (*on_free_cmd)(struct scst_cmd *cmd);
/*
* This function allows target driver to handle data buffer
* allocations on its own.
*
* Target driver doesn't have to always allocate buffer in this
* function, but if it decide to do it, it must check that
* scst_cmd_get_data_buff_alloced() returns 0, otherwise to avoid
* double buffer allocation and memory leaks tgt_alloc_data_buf() shall
* fail.
*
* Shall return 0 in case of success or < 0 (preferably -ENOMEM)
* in case of error, or > 0 if the regular SCST allocation should be
* done. In case of returning successfully,
* scst_cmd->tgt_i_data_buf_alloced will be set by SCST.
*
* It is possible that both target driver and dev handler request own
* memory allocation. In this case, data will be memcpy() between
* buffers, where necessary.
*
* If allocation in atomic context - cf. scst_cmd_atomic() - is not
* desired or fails and consequently < 0 is returned, this function
* will be re-called in thread context.
*
* Please note that the driver will have to handle itself all relevant
* details such as scatterlist setup, highmem, freeing the allocated
* memory, etc.
*
* OPTIONAL.
*/
int (*tgt_alloc_data_buf)(struct scst_cmd *cmd);
/*
* This function informs the driver that data
* buffer corresponding to the said command have now been
* allocated and other preprocessing tasks have been done.
* A target driver could need to do some actions at this stage.
* After the target driver done the needed actions, it shall call
* scst_restart_cmd() in order to continue processing this command.
* In case of preliminary the command completion, this function will
* also be called before xmit_response().
*
* Called only if the cmd is queued using scst_cmd_init_stage1_done()
* instead of scst_cmd_init_done().
*
* Returns void, the result is expected to be returned using
* scst_restart_cmd().
*
* This command is expected to be NON-BLOCKING.
* If it is blocking, consider to set threads_num to some none 0 number.
*
* Pay attention to "atomic" attribute of the cmd, which can be get
* by scst_cmd_atomic(): it is true if the function called in the
* atomic (non-sleeping) context.
*
* OPTIONAL.
*/
void (*preprocessing_done)(struct scst_cmd *cmd);
/*
* This function informs the driver that the said command is about
* to be executed.
*
* Returns one of the SCST_PREPROCESS_* constants.
*
* This command is expected to be NON-BLOCKING.
* If it is blocking, consider to set threads_num to some none 0 number.
*
* OPTIONAL
*/
int (*pre_exec)(struct scst_cmd *cmd);
/*
* This function informs the driver that all affected by the
* corresponding task management function commands have beed completed.
* No return value expected.
*
* This function is expected to be NON-BLOCKING.
*
* Called without any locks held from a thread context.
*
* OPTIONAL
*/
void (*task_mgmt_affected_cmds_done)(struct scst_mgmt_cmd *mgmt_cmd);
/*
* This function informs the driver that the corresponding task
* management function has been completed, i.e. all the corresponding
* commands completed and freed. No return value expected.
*
* This function is expected to be NON-BLOCKING.
*
* Called without any locks held from a thread context.
*
* MUST HAVE if the target supports task management.
*/
void (*task_mgmt_fn_done)(struct scst_mgmt_cmd *mgmt_cmd);
/*
* Called to notify target driver that the command is being aborted.
* If target driver wants to redirect processing to some outside
* processing, it should get it using scst_cmd_get(). Since this
* function is invoked from the context of a task management function
* it runs asynchronously with the regular command processing finite
* state machine. In other words, it is only safe to invoke functions
* like scst_tgt_cmd_done() or scst_rx_data() from this callback
* function if the target driver owns the command and if appropriate
* measures have been taken to avoid that the target driver would
* invoke one of these functions from the regular command processing
* path. Note: if scst_tgt_cmd_done() or scst_rx_data() is invoked
* from this callback function these must be invoked with the
* SCST_CONTEXT_THREAD argument.
*
* OPTIONAL
*/
void (*on_abort_cmd)(struct scst_cmd *cmd);
/*
* This function should detect the target adapters that
* are present in the system. The function should return a value
* >= 0 to signify the number of detected target adapters.
* A negative value should be returned whenever there is
* an error.
*
* OBSOLETE
*/
int (*detect)(struct scst_tgt_template *tgt_template);
/*
* This function should free up the resources allocated to the device.
* The function should return 0 to indicate successful release
* or a negative value if there are some issues with the release.
* In the current version the return value is ignored.
*
* MUST HAVE
*/
int (*release)(struct scst_tgt *tgt);
/*
* This function is used for Asynchronous Event Notifications.
*
* Returns one of the SCST_AEN_RES_* constants.
* After AEN is sent, target driver must call scst_aen_done() and,
* optionally, scst_set_aen_delivery_status().
*
* This function is expected to be NON-BLOCKING, but can sleep.
*
* This function must be prepared to handle AENs between calls for the
* corresponding session of scst_unregister_session() and
* unreg_done_fn() callback called or before scst_unregister_session()
* returned, if its called in the blocking mode. AENs for such sessions
* should be ignored.
*
* MUST HAVE, if low-level protocol supports AENs.
*/
int (*report_aen)(struct scst_aen *aen);
/*
* This function returns in tr_id the corresponding to sess initiator
* port TransportID in the form as it's used by PR commands, see
* "Transport Identifiers" in SPC. Space for the initiator port
* TransportID must be allocated via kmalloc(). Caller supposed to
* kfree() it, when it isn't needed anymore.
*
* If sess is NULL, this function must return TransportID PROTOCOL
* IDENTIFIER for the requested target.
*
* Returns 0 on success or negative error code otherwise.
*
* SHOULD HAVE, because it's required for Persistent Reservations.
*/
int (*get_initiator_port_transport_id)(struct scst_tgt *tgt,
struct scst_session *sess, uint8_t **transport_id);
/*
* This function allows to enable or disable particular target.
* A disabled target doesn't receive and process any SCSI commands.
*
* SHOULD HAVE to avoid race when there are connected initiators,
* while target not yet completed the initial configuration. In this
* case the too early connected initiators would see not those devices,
* which they intended to see.
*
* If you are sure your target driver doesn't need enabling target,
* you should set enabled_attr_not_needed in 1.
*/
int (*enable_target)(struct scst_tgt *tgt, bool enable);
/*
* This function shows if particular target is enabled or not.
*
* SHOULD HAVE, see above why.
*/
bool (*is_target_enabled)(struct scst_tgt *tgt);
/*
* This function adds a virtual target.
*
* If both add_target and del_target callbacks defined, then this
* target driver supposed to support virtual targets. In this case
* an "mgmt" entry will be created in the sysfs root for this driver.
* The "mgmt" entry will support 2 commands: "add_target" and
* "del_target", for which the corresponding callbacks will be called.
* Also target driver can define own commands for the "mgmt" entry, see
* mgmt_cmd and mgmt_cmd_help below.
*
* This approach allows uniform targets management to simplify external
* management tools like scstadmin. See README for more details.
*
* Either both add_target and del_target must be defined, or none.
*
* MUST HAVE if virtual targets are supported.
*/
ssize_t (*add_target)(const char *target_name, char *params);
/*
* This function deletes a virtual target. See comment for add_target
* above.
*
* MUST HAVE if virtual targets are supported.
*/
ssize_t (*del_target)(const char *target_name);
/*
* This function called if not "add_target" or "del_target" command is
* sent to the mgmt entry (see comment for add_target above). In this
* case the command passed to this function as is in a string form.
*
* OPTIONAL.
*/
ssize_t (*mgmt_cmd)(char *cmd);
/*
* Forcibly close a session. Note: this function may operate
* asynchronously - there is no guarantee the session will actually
* have been closed at the time this function returns. May be called
* with scst_mutex held. Activity may be suspended while this function
* is invoked. May sleep but must not wait until session
* unregistration finished. Must return 0 upon success and -EINTR if
* the session has not been closed because a signal has been received.
*
* OPTIONAL
*/
int (*close_session)(struct scst_session *sess);
/*
* Should return physical transport version. Used in the corresponding
* INQUIRY version descriptor. See SPC for the list of available codes.
*
* OPTIONAL
*/
uint16_t (*get_phys_transport_version)(struct scst_tgt *tgt);
/*
* Should return SCSI transport version. Used in the corresponding
* INQUIRY version descriptor. See SPC for the list of available codes.
*
* OPTIONAL
*/
uint16_t (*get_scsi_transport_version)(struct scst_tgt *tgt);
/*
* Name of the template. Must be unique to identify
* the template. MUST HAVE
*/
const char name[SCST_MAX_NAME];
/*
* Number of additional threads to the pool of dedicated threads.
* Used if xmit_response() or rdy_to_xfer() is blocking.
* It is the target driver's duty to ensure that not more, than that
* number of threads, are blocked in those functions at any time.
*/
int threads_num;
/* Optional default log flags */
const unsigned long default_trace_flags;
/* Optional pointer to trace flags */
unsigned long *trace_flags;
/* Optional local trace table */
struct scst_trace_log *trace_tbl;
/* Optional local trace table help string */
const char *trace_tbl_help;
/* sysfs attributes, if any */
const struct attribute **tgtt_attrs;
/* sysfs target attributes, if any */
const struct attribute **tgt_attrs;
/* sysfs session attributes, if any */
const struct attribute **sess_attrs;
/* sysfs ACG attributes, if any */
const struct attribute **acg_attrs;
/* Optional help string for mgmt_cmd commands */
const char *mgmt_cmd_help;
/* List of parameters for add_target command, if any */
const char *add_target_parameters;
/*
* List of optional, i.e. which could be added by add_attribute command
* and deleted by del_attribute command, sysfs attributes, if any.
* Helpful for scstadmin to work correctly.
*/
const char *tgtt_optional_attributes;
/*
* List of optional, i.e. which could be added by add_target_attribute
* command and deleted by del_target_attribute command, sysfs
* attributes, if any. Helpful for scstadmin to work correctly.
*/
const char *tgt_optional_attributes;
/** Private, must be inited to 0 by memset() **/
/* List of targets per template, protected by scst_mutex */
struct list_head tgt_list;
/* List entry of global templates list */
struct list_head scst_template_list_entry;
struct kobject tgtt_kobj; /* target driver sysfs entry */
/* Number of currently active sysfs mgmt works (scst_sysfs_work_item) */
int tgtt_active_sysfs_works_count;
/* sysfs release completion */
struct completion *tgtt_kobj_release_cmpl;
/*
* Optional method that writes the serial number of a target device in
* [buf, buf+size) and returns the number of bytes written.
*
* Note: SCST can be configured such that a device can be accessed
* from several different transports at the same time. It is important
* that all clients see the same USN for proper operation. Overriding
* the serial number can lead to subtle misbehavior. Particularly,
* "usn" sysfs attribute of the corresponding devices will still show
* the devices generated or assigned serial numbers.
*/
int (*get_serial)(const struct scst_tgt_dev *tgt_dev, char *buf,
int size);
};
/*
* Threads pool types. Changing them don't forget to change
* the corresponding *_STR values in scst_const.h!
*/
enum scst_dev_type_threads_pool_type {
/* Each initiator will have dedicated threads pool. */
SCST_THREADS_POOL_PER_INITIATOR = 0,
/* All connected initiators will use shared threads pool */
SCST_THREADS_POOL_SHARED,
/* Invalid value for scst_parse_threads_pool_type() */
SCST_THREADS_POOL_TYPE_INVALID,
};
/*
* SCST dev handler template: defines dev handler's parameters and callback
* functions.
*
* MUST HAVEs define functions that are expected to be defined in order to
* work. OPTIONAL says that there is a choice.
*/
struct scst_dev_type {
/* SCSI type of the supported device. MUST HAVE */
int type;
/*
* True, if corresponding function supports execution in
* the atomic (non-sleeping) context
*/
unsigned parse_atomic:1;
unsigned dev_alloc_data_buf_atomic:1;
unsigned dev_done_atomic:1;
/*
* Should be set if the device wants to receive notification of
* Persistent Reservation commands (PR OUT only)
* Note: The notification will not be send if the command failed
*/
unsigned pr_cmds_notifications:1;
/*
* Set if the Copy Manager can auto assing to devices of this
* template on their registration.
*/
unsigned auto_cm_assignment_possible:1;
/*
* Set if this handler does not have run time devices management
*/
unsigned no_mgmt:1;
/*
* Called to parse CDB from the cmd and initialize
* cmd->bufflen and cmd->data_direction (both - REQUIRED).
*
* Returns the command's next state or SCST_CMD_STATE_DEFAULT,
* if the next default state should be used, or
* SCST_CMD_STATE_NEED_THREAD_CTX if the function called in atomic
* context, but requires sleeping, or SCST_CMD_STATE_STOP if the
* command should not be further processed for now. In the
* SCST_CMD_STATE_NEED_THREAD_CTX case the function
* will be recalled in the thread context, where sleeping is allowed.
*
* Pay attention to "atomic" attribute of the cmd, which can be get
* by scst_cmd_atomic(): it is true if the function called in the
* atomic (non-sleeping) context.
*
* MUST HAVE
*/
int (*parse)(struct scst_cmd *cmd);
/*
* This function allows dev handler to handle data buffer
* allocations on its own.
*
* Returns the command's next state or SCST_CMD_STATE_DEFAULT,
* if the next default state should be used, or
* SCST_CMD_STATE_NEED_THREAD_CTX if the function called in atomic
* context, but requires sleeping, or SCST_CMD_STATE_STOP if the
* command should not be further processed for now. In the
* SCST_CMD_STATE_NEED_THREAD_CTX case the function
* will be recalled in the thread context, where sleeping is allowed.
*
* Pay attention to "atomic" attribute of the cmd, which can be get
* by scst_cmd_atomic(): it is true if the function called in the
* atomic (non-sleeping) context.
*
* OPTIONAL
*/
int (*dev_alloc_data_buf)(struct scst_cmd *cmd);
/*
* Called to execute CDB. Useful, for instance, to implement
* data caching. The result of CDB execution is reported via
* cmd->scst_cmd_done() callback.
* Returns:
* - SCST_EXEC_COMPLETED - the cmd is done, go to other ones
* - SCST_EXEC_NOT_COMPLETED - the cmd should be sent to SCSI
* mid-level.
*
* If this function provides sync execution, you should to set up
* dedicated threads by setting threads_num > 0.
*
* Dev handlers implementing internal queuing in their exec() callback
* should call scst_check_local_events() just before the actual
* command's execution (i.e. after it's taken from the internal queue).
*
* OPTIONAL, if not set, the commands will be sent directly to SCSI
* device.
*/
enum scst_exec_res (*exec)(struct scst_cmd *cmd);
/*
* Called to notify dev handler about the result of cmd execution
* and perform some post processing. Cmd's fields is_send_status and
* resp_data_len should be set by this function, but SCST offers good
* defaults.
* Returns the command's next state or SCST_CMD_STATE_DEFAULT,
* if the next default state should be used, or
* SCST_CMD_STATE_NEED_THREAD_CTX if the function called in atomic
* context, but requires sleeping. In the last case, the function
* will be recalled in the thread context, where sleeping is allowed.
*
* Pay attention to "atomic" attribute of the cmd, which can be get
* by scst_cmd_atomic(): it is true if the function called in the
* atomic (non-sleeping) context.
*
* OPTIONAL
*/
int (*dev_done)(struct scst_cmd *cmd);
/*
* Called to notify dev handler that the command is about to be freed.
*
* Could be called on IRQ context.
*
* OPTIONAL
*/
void (*on_free_cmd)(struct scst_cmd *cmd);
/*
* Called during EXTENDED COPY command processing to let dev handler
* try to remap blocks at first. Upon finish, the dev handler supposed
* to call scst_ext_copy_remap_done(). See description of this
* function for more details.
*
* In case of error, the dev handler should set the corresponding sense
* to cmd and then call scst_ext_copy_remap_done(cmd, NULL, 0).
*
* It is highly recommended that in the normal circumstances
* scst_ext_copy_remap_done() called from another thread context,
* because otherwise there will be recursion in the segments processing.
* Hopefully, this thread context switch is natural for such
* potentially long operation.
*
* OPTIONAL
*/
void (*ext_copy_remap)(struct scst_cmd *cmd,
struct scst_ext_copy_seg_descr *descr);
/*
* Called to notify dev handler that a ALUA state change is about to
* be started. Can be used to close open file handlers, which might
* prevent the state switch.
*
* Called under scst_dg_mutex and no activities on the dev handler level
* (for implicit ALUA case supposed to be done by the user space via
* "block" sysfs attribute as described in the README).
*
* OPTIONAL
*/
void (*on_alua_state_change_start)(struct scst_device *dev,
enum scst_tg_state old_state, enum scst_tg_state new_state);
/*
* Called to notify dev handler that a ALUA state change is about to
* be finished. Can be used to (re)open file handlers closed in
* on_alua_state_change_start().
*
* Called under scst_dg_mutex and no activities on the dev handler level
* (for implicit ALUA case supposed to be done by the user space via
* "block" sysfs attribute as described in the README).
*
* OPTIONAL
*/
void (*on_alua_state_change_finish)(struct scst_device *dev,
enum scst_tg_state old_state, enum scst_tg_state new_state);
/*
* Called to notify dev handler that a task management command received
*
* Can be called under many internal SCST locks, including under
* disabled IRQs, so dev handler should be careful with locking and,
* if necessary, pass processing somewhere outside (in a work, e.g.)
*
* But at the moment it's called under disabled IRQs only for
* SCST_ABORT_TASK, however dev handler using it should add a BUG_ON
* trap to catch if it's changed in future.
*
* OPTIONAL
*/
void (*task_mgmt_fn_received)(struct scst_mgmt_cmd *mgmt_cmd,
struct scst_tgt_dev *tgt_dev);
/*
* Called to execute a task management command. On any problem, error
* code (one of SCST_MGMT_STATUS_* codes) should be set using function
* scst_mgmt_cmd_set_status().
*
* Can be called under many internal SCST locks, including under
* disabled IRQs, so dev handler should be careful with locking and,
* if necessary, pass processing somewhere outside (in a work, e.g.)
*
* But at the moment it's called under disabled IRQs only for
* SCST_ABORT_TASK, however dev handler using it should add a BUG_ON
* trap to catch if it's changed in future.
*
* OPTIONAL
*/
void (*task_mgmt_fn_done)(struct scst_mgmt_cmd *mgmt_cmd,
struct scst_tgt_dev *tgt_dev);
/*
* Called to reassign retained states (mode pages, etc.) from
* old_tgt_dev to new_tgt_dev during nexus loss (iSCSI sessions
* reinstatement, etc.) processing.
*
* Can be called under scst_mutex.
*
* OPTIONAL
*/
void (*reassign_retained_states)(struct scst_tgt_dev *new_tgt_dev,
struct scst_tgt_dev *old_tgt_dev);
/*
* Called to notify dev handler that its sg_tablesize is too low to
* satisfy this command's data transfer requirements. Should return
* true if exec() callback will split this command's CDB on smaller
* transfers, false otherwise.
*
* Could be called on SIRQ context.
*
* MUST HAVE, if dev handler supports CDB splitting.
*/
bool (*on_sg_tablesize_low)(struct scst_cmd *cmd);
/*
* Called to return array of supported opcodes in out_supp_opcodes
* argument with out_supp_opcodes_cnt elements count or execute
* REPORT SUPPORTED OPERATION CODES command in place. Must return
* 0 on success or any other code otherwise. In the latter case,
* cmd supposed to have correct sense set.
*
* OPTIONAL
*/
int (*get_supported_opcodes)(struct scst_cmd *cmd,
const struct scst_opcode_descriptor ***out_supp_opcodes,
int *out_supp_opcodes_cnt);
/*
* Called to put (release) array of supported opcodes returned
* by get_supported_opcodes() callback.
*
* OPTIONAL
*/
void (*put_supported_opcodes)(struct scst_cmd *cmd,
const struct scst_opcode_descriptor **supp_opcodes,
int supp_opcodes_cnt);
/*
* Called when new device is attaching to the dev handler
* Returns 0 on success, error code otherwise.
*
* OPTIONAL
*/
int (*attach)(struct scst_device *dev);
/*
* Called when a device is detaching from the dev handler.
*
* OPTIONAL
*/
void (*detach)(struct scst_device *dev);
/*
* Called when new tgt_dev (session) is attaching to the dev handler.
* Returns 0 on success, error code otherwise.
*
* OPTIONAL
*/
int (*attach_tgt)(struct scst_tgt_dev *tgt_dev);
/*
* Called when tgt_dev (session) is detaching from the dev handler.
*
* OPTIONAL
*/
void (*detach_tgt)(struct scst_tgt_dev *tgt_dev);
/*
* This function adds a virtual device.
*
* If both add_device and del_device callbacks defined, then this
* dev handler supposed to support adding/deleting virtual devices.
* In this case an "mgmt" entry will be created in the sysfs root for
* this handler. The "mgmt" entry will support 2 commands: "add_device"
* and "del_device", for which the corresponding callbacks will be called.
* Also dev handler can define own commands for the "mgmt" entry, see
* mgmt_cmd and mgmt_cmd_help below.
*
* This approach allows uniform devices management to simplify external
* management tools like scstadmin. See README for more details.
*
* Either both add_device and del_device must be defined, or none.
*
* MUST HAVE if virtual devices are supported.
*/
ssize_t (*add_device)(const char *device_name, char *params);
/*
* This function deletes a virtual device. See comment for add_device
* above.
*
* MUST HAVE if virtual devices are supported.
*/
ssize_t (*del_device)(const char *device_name);
/*
* This function called if not "add_device" or "del_device" command is
* sent to the mgmt entry (see comment for add_device above). In this
* case the command passed to this function as is in a string form.
*
* OPTIONAL.
*/
ssize_t (*mgmt_cmd)(char *cmd);
/*
* Name of the dev handler. Must be unique. MUST HAVE.
*
* It's SCST_MAX_NAME + few more bytes to match scst_user expectations.
*/
char name[SCST_MAX_NAME + 10];
/*
* Number of threads in this handler's devices' threads pools.
* If 0 - no threads will be created, if <0 - creation of the threads
* pools is prohibited. Also pay attention to threads_pool_type below.
*/
int threads_num;
/*
* Maximum count of uncompleted commands that an initiator could
* queue on any device of this handler by default. Then it will start
* getting TASK QUEUE FULL status.
*/
int max_tgt_dev_commands;
/* Threads pool type. Valid only if threads_num > 0. */
enum scst_dev_type_threads_pool_type threads_pool_type;
/* Optional default log flags */
const unsigned long default_trace_flags;
/* Optional pointer to trace flags */
unsigned long *trace_flags;
/* Optional local trace table */
struct scst_trace_log *trace_tbl;
/* Optional local trace table help string */
const char *trace_tbl_help;
/* Optional help string for mgmt_cmd commands */
const char *mgmt_cmd_help;
/*
* Array with parameters for add_device command, if any. NULL
* terminated.
*/
const char *const *add_device_parameters;
/*
* List of optional, i.e. which could be added by add_attribute command
* and deleted by del_attribute command, sysfs attributes, if any.
* Helpful for scstadmin to work correctly.
*/
const char *devt_optional_attributes;
/*
* List of optional, i.e. which could be added by add_device_attribute
* command and deleted by del_device_attribute command, sysfs
* attributes, if any. Helpful for scstadmin to work correctly.
*/
const char *dev_optional_attributes;
/* sysfs attributes, if any */
const struct attribute **devt_attrs;
/* sysfs device attributes, if any */
const struct attribute **dev_attrs;
/* Pointer to dev handler's private data */
void *devt_priv;
/* Pointer to parent dev type in the sysfs hierarchy */
struct scst_dev_type *parent;
struct module *module;
/** Private, must be inited to 0 by memset() **/
/* list entry in scst_(virtual_)dev_type_list */
struct list_head dev_type_list_entry;
struct kobject devt_kobj; /* main handlers/driver */
/* Number of currently active sysfs mgmt works (scst_sysfs_work_item) */
int devt_active_sysfs_works_count;
/* To wait until devt_kobj released */
struct completion *devt_kobj_release_compl;
};
/*
* An SCST target, analog of SCSI target port.
*/
struct scst_tgt {
/* List of remote sessions per target, protected by scst_mutex */
struct list_head sess_list;
/*
* List of remote sessions registered in sysfs per target, protected
* by scst_mutex.
*/
struct list_head sysfs_sess_list;
/* List entry of targets per template (tgts_list) */
struct list_head tgt_list_entry;
struct scst_tgt_template *tgtt; /* corresponding target template */
struct scst_acg *default_acg; /* default acg for this target */
struct list_head tgt_acg_list; /* target ACG groups */
/*
* Set, if this target is forwarding target, i.e. does not check
* any local SCSI events (reservations, etc.). Those event supposed
* to be checked on the another, requester's side.
*/
unsigned tgt_forwarding:1;
/* Per target analog of the corresponding driver's fields */
unsigned tgt_dif_supported:1;
unsigned tgt_hw_dif_type1_supported:1;
unsigned tgt_hw_dif_type2_supported:1;
unsigned tgt_hw_dif_type3_supported:1;
unsigned tgt_hw_dif_ip_supported:1;
unsigned tgt_hw_dif_same_sg_layout_required:1;
/*
* Maximum SG table size. Needed here, since different cards on the
* same target template can have different SG table limitations.
*/
int sg_tablesize;
const int *tgt_supported_dif_block_sizes;
/* Used for storage of target driver private stuff */
void *tgt_priv;
/*
* The following fields used to store and retry cmds if target's
* internal queue is full, so the target is unable to accept
* the cmd returning QUEUE FULL.
* They protected by tgt_lock, where necessary.
*/
bool retry_timer_active;
int retry_cmds;
struct timer_list retry_timer;
struct list_head retry_cmd_list;
spinlock_t tgt_lock;
/* Used to wait until session finished to unregister */
wait_queue_head_t unreg_waitQ;
/* Name of the target */
char *tgt_name;
/* User comment to it to let easier distinguish targets */
char *tgt_comment;
uint16_t rel_tgt_id;
/* How many DIF failures detected on this target on the corresponding stage */
atomic_t tgt_dif_app_failed_tgt, tgt_dif_ref_failed_tgt, tgt_dif_guard_failed_tgt;
atomic_t tgt_dif_app_failed_scst, tgt_dif_ref_failed_scst, tgt_dif_guard_failed_scst;
atomic_t tgt_dif_app_failed_dev, tgt_dif_ref_failed_dev, tgt_dif_guard_failed_dev;
/* sysfs release completion */
struct completion *tgt_kobj_release_cmpl;
struct kobject tgt_kobj; /* main targets/target kobject */
struct kobject *tgt_sess_kobj; /* target/sessions/ */
struct kobject *tgt_luns_kobj; /* target/luns/ */
struct kobject *tgt_ini_grp_kobj; /* target/ini_groups/ */
};
/**
* struct scst_lat_stat_entry - SCST command processing latency data
* @last_update: Time of last update of this data structure in 100 ns.
* @count: Number of samples for which statistics have been gathered.
* @last_update_tsc: Time of the last update of this data structure in 100
* clock cycles.
* @min: Minimum processing time in nanoseconds.
* @max: Maximum processing time.
* @sum: Processing time sum.
* @sumsq: Sum of the squares of the processing times.
* @minc, @maxc, @sumc, @sumsqc: Similar to the above but in hundred clock
* cycles instead of nanoseconds.
*
* Time unit for the uint64_t numbers: 100 ns.
*
* Size: 96 bytes.
*/
struct scst_lat_stat_entry {
ktime_t last_update;
uint32_t count;
uint32_t padding;
#ifdef SCST_MEASURE_CLOCK_CYCLES
uint64_t last_update_tsc;
#endif
uint64_t min;
uint64_t max;
uint64_t sum;
uint64_t sumsq;
#ifdef SCST_MEASURE_CLOCK_CYCLES
uint64_t minc;
uint64_t maxc;
uint64_t sumc;
uint64_t sumsqc;
#endif
};
/*
* lat_stats is an array with three indices:
* - Logarithm base 2 of the data length minus 9.
* - Data direction (SCST_DATA_*).
* - SCST command state.
*
* Size: 11 * 4 * 25 * 96 = 105600 bytes.
*/
#define SCST_STATS_LOG2_SZ_OFFSET 9
#define SCST_STATS_MAX_LOG2_SZ 11
struct scst_lat_stats {
struct scst_lat_stat_entry
ls[SCST_STATS_MAX_LOG2_SZ][4][SCST_CMD_STATE_COUNT];
};
struct scst_io_stat_entry {
uint64_t cmd_count;
uint64_t io_byte_count;
uint64_t unaligned_cmd_count;
};
/*
* SCST session, analog of SCSI I_T nexus
*/
struct scst_session {
/*
* Initialization phase, one of SCST_SESS_IPH_* constants, protected by
* sess_list_lock
*/
int init_phase;
struct scst_tgt *tgt; /* corresponding target */
/* Used for storage of target driver private stuff */
void *sess_tgt_priv;
/* session's async flags */
unsigned long sess_aflags;
/* protects sess_tgt_dev_list[] modifications */
struct mutex tgt_dev_list_mutex;
/*
* Hash list for tgt_dev's for this session with size and fn. Reading
* is allowed either when holding an RCU read lock or when holding
* tgt_dev_list_mutex. Modifying is only allowed when holding
* tgt_dev_list_mutex.
*/
#define SESS_TGT_DEV_LIST_HASH_SIZE (1 << 5)
#define SESS_TGT_DEV_LIST_HASH_FN(val) ((val) & (SESS_TGT_DEV_LIST_HASH_SIZE - 1))
struct list_head sess_tgt_dev_list[SESS_TGT_DEV_LIST_HASH_SIZE];
/*
* List of cmds in this session. Protected by sess_list_lock.
*
* We must always keep commands in the sess list from the
* very beginning, because otherwise they can be missed during
* TM processing.
*/
struct list_head sess_cmd_list ____cacheline_aligned_in_smp;
spinlock_t sess_list_lock; /* protects sess_cmd_list, etc */
struct percpu_ref refcnt; /* get/put counter */
/*
* Alive commands for this session. ToDo: make it part of the common
* IO flow control.
*/
atomic_t sess_cmd_count;
/* Some statistics. Protected by sess_list_lock. */
struct scst_io_stat_entry io_stats[SCST_DATA_DIR_MAX];
/* Access control for this session and list entry there */
struct scst_acg *acg;
/* Initiator port transport id */
uint8_t *transport_id;
/* List entry for the sessions list inside ACG */
struct list_head acg_sess_list_entry;
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20))
struct delayed_work hw_pending_work;
#else
struct work_struct hw_pending_work;
#endif
/* Name of attached initiator */
const char *initiator_name;
/* Unique session name: initiator name + optional _%d. */
const char *sess_name;
/* List entry of sessions per target */
struct list_head sess_list_entry;
/* Per target list entry for sessions registered in sysfs. */
struct list_head sysfs_sess_list_entry;
/* List entry for the list that keeps session, waiting for the init */
struct list_head sess_init_list_entry;
/*
* List entry for the list that keeps session, waiting for the shutdown
*/
struct list_head sess_shut_list_entry;
/*
* Lists of deferred during session initialization commands.
* Protected by sess_list_lock.
*/
struct list_head init_deferred_cmd_list;
struct list_head init_deferred_mcmd_list;
/*
* Shutdown phase, one of SCST_SESS_SPH_* constants, unprotected.
* Async. relating to init_phase, must be a separate variable, because
* session could be unregistered before async. registration is finished.
*/
unsigned long shut_phase;
/* Used if scst_unregister_session() called in wait mode */
struct completion *shutdown_compl;
/*
* Keep list IDs for Extended Copy commands sent over this session.
* Protected by scst_cm_lock.
*/
struct list_head sess_cm_list_id_list;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20)
struct work_struct sess_cm_list_id_cleanup_work;
#else
struct delayed_work sess_cm_list_id_cleanup_work;
#endif
/* sysfs release completion */
struct completion *sess_kobj_release_cmpl;
unsigned int sess_mq:1; /* Multi-queue session, i.e. >1 sessions per same initiator */
unsigned int sess_kobj_ready:1;
struct kobject sess_kobj; /* session sysfs entry */
struct kobject *lat_kobj;
/*
* Functions and data for user callbacks from scst_register_session()
* and scst_unregister_session()
*/
void *reg_sess_data;
void (*init_result_fn)(struct scst_session *sess, void *data,
int result);
void (*unreg_done_fn)(struct scst_session *sess);
/*
* Latency measurement data.
*/
spinlock_t lat_stats_lock;
struct scst_lat_stats *lat_stats;
};
/*
* SCST_PR_ABORT_ALL TM function helper structure
*/
struct scst_pr_abort_all_pending_mgmt_cmds_counter {
/*
* How many there are pending for this cmd SCST_PR_ABORT_ALL TM
* commands.
*/
atomic_t pr_abort_pending_cnt;
/* Saved completion routine */
void (*saved_cmd_done)(struct scst_cmd *cmd, int next_state,
enum scst_exec_context pref_context);
/*
* How many there are pending for this cmd SCST_PR_ABORT_ALL TM
* commands, which not yet aborted all affected commands and
* a completion to signal, when it's done.
*/
atomic_t pr_aborting_cnt;
struct completion pr_aborting_cmpl;
};
/*
* Structure to control commands' queuing and threads pool processing the queue
*/
struct scst_cmd_threads {
spinlock_t cmd_list_lock;
struct list_head active_cmd_list; /* commands queue */
wait_queue_head_t cmd_list_waitQ;
struct io_context *io_context; /* IO context of the threads pool */
int io_context_refcnt;
bool io_context_ready;
wait_queue_head_t ioctx_wq;
/* io_context_mutex protects io_context and io_context_refcnt. */
struct mutex io_context_mutex;
spinlock_t thr_lock; /* Protects nr_threads and threads_list */
int nr_threads; /* number of processing threads */
struct list_head threads_list; /* processing threads */
struct list_head lists_list_entry;
};
int scst_set_thr_cpu_mask(struct scst_cmd_threads *cmd_threads,
cpumask_t *cpu_mask);
struct scst_pr_dlm_data;
/*
* DLM lock status block with completion for notifying completion of
* synchronous DLM lock operations.
*/
struct scst_lksb {
struct dlm_lksb lksb;
struct completion compl;
struct scst_pr_dlm_data *pr_dlm;
};
/*
* Used to execute cmd's in order of arrival, honoring SCSI task attributes
*/
struct scst_order_data {
/*
* All fields, when needed, protected by sn_lock. Curr_sn must have
* the same type as expected_sn to overflow simultaneously!
*/
struct list_head skipped_sn_list;
struct list_head deferred_cmd_list;
spinlock_t sn_lock; /* IRQ lock */
int hq_cmd_count;
/* Set if the prev cmd was ORDERED */
bool prev_cmd_ordered;
/*
* tgt_dev initiated ACA, if any, or 0 otherwise. It can be deleted
* and freed during LUN deletion, so must not be dereferenced.
*/
unsigned long aca_tgt_dev;
/* Active ACA cmd, if any */
struct scst_cmd *aca_cmd;
int def_cmd_count;
unsigned int expected_sn;
unsigned int curr_sn;
int pending_simple_inc_expected_sn;
atomic_t *cur_sn_slot;
atomic_t sn_slots[15];
/*
* Used to serialized scst_cmd_init_done() if the corresponding
* session's target template has multithreaded_init_done set
*/
spinlock_t init_done_lock;
};
struct scst_orig_sg_data {
int *p_orig_sg_cnt;
int orig_sg_cnt;
struct scatterlist *orig_sg_entry;
int orig_entry_offs, orig_entry_len;
};
/*
* SCST command, analog of I_T_L_Q nexus or task
*/
struct scst_cmd {
/* List entry for below *_cmd_threads */
struct list_head cmd_list_entry;
/* Pointer to lists of commands with the lock */
struct scst_cmd_threads *cmd_threads;
/* Assigned processing thread (for better CPU affinity) */
struct scst_cmd_thread_t *cmd_thr;
atomic_t cmd_ref;
struct scst_session *sess; /* corresponding session */
atomic_t *cpu_cmd_counter;
/* Cmd state, one of SCST_CMD_STATE_* constants */
enum scst_cmd_state state;
/*************************************************************
** Cmd's flags
*************************************************************/
/*
* Set if cmd was sent for execution to optimize aborts waiting.
* Also it is a sign under contract that if inc_expected_sn_on_done
* is not set, the thread setting it is committing obligation to
* call scst_inc_expected_sn() after this cmd was sent to exec.
*/
unsigned int sent_for_exec:1;
/* Set if cmd's SN was set */
unsigned int sn_set:1;
/* Set if increment expected_sn in cmd->scst_cmd_done() */
unsigned int inc_expected_sn_on_done:1;
/* Set if the cmd's action is completed */
unsigned int completed:1;
/* Set if we should ignore Unit Attention in scst_check_sense() */
unsigned int ua_ignore:1;
/* Set if cmd is being processed in atomic context */
unsigned int atomic:1;
/* Set if this command was sent in double UA possible state */
unsigned int double_ua_possible:1;
/* Set if DIF check for just read data was deferred to thread context */
unsigned int deferred_dif_read_check:1;
/* Set if this command contains status */
unsigned int is_send_status:1;
/* Set if cmd is being retried */
unsigned int retry:1;
/* Set if cmd is internally generated */
unsigned int internal:1;
/* Set if local events should be checked for internally generated cmd */
unsigned int internal_check_local_events:1;
/* Set if the blocking machinery should be bypassed for this cmd */
unsigned int bypass_blocking:1;
/* Set if the device was blocked by scst_check_blocked_dev() */
unsigned int unblock_dev:1;
/* Set if scst_dec_on_dev_cmd() call is needed on the cmd's finish */
unsigned int dec_on_dev_needed:1;
/* Set if cmd is on dev's exec_cmd_list */
unsigned int on_dev_exec_list:1;
/* Set if this cmd passed check for SCSI atomicity */
unsigned int scsi_atomicity_checked:1;
/* Set if cmd is queued as hw pending */
unsigned int cmd_hw_pending:1;
/* Set if cmd has NACA bit set in CDB */
unsigned int cmd_naca:1;
/* Set if cmd was allowed during ACA */
unsigned int cmd_aca_allowed:1;
/*
* Set if the target driver wants to alloc data buffers on its own.
* In this case tgt_alloc_data_buf() must be provided in the target
* driver template.
*/
unsigned int tgt_need_alloc_data_buf:1;
/*
* Set by SCST if the custom data buffer allocated by the target driver
* or, for internal commands, by SCST core.
*/
unsigned int tgt_i_data_buf_alloced:1;
/* Set if custom data buffer allocated by dev handler */
unsigned int dh_data_buf_alloced:1;
/*
* Set length of each member of dif_sg was normalized to match
* tgtt->hw_dif_same_sg_layout_required requirements
*/
unsigned int dif_sg_normalized:1;
/* Set if the target driver called scst_set_expected() */
unsigned int expected_values_set:1;
/* Set if the SG buffer was modified by scst_adjust_sg*() */
unsigned int sg_buff_modified:1;
/* Set if the DIF SG buffer was modified by scst_adjust_sg*() */
unsigned int dif_sg_buff_modified:1;
/*
* Set if cmd buffer was vmallocated and copied from more
* then one sg chunk
*/
unsigned int sg_buff_vmallocated:1;
/*
* Set if scst_cmd_init_stage1_done() called and the target
* want that preprocessing_done() will be called
*/
unsigned int preprocessing_only:1;
/* Set if hq_cmd_count was incremented */
unsigned int hq_cmd_inced:1;
/*
* Set if scst_cmd_init_stage1_done() called and the target wants
* that the SN for the cmd won't be assigned until scst_restart_cmd()
*/
unsigned int set_sn_on_restart_cmd:1;
/* Set if the cmd's must not use sgv cache for data buffer */
unsigned int no_sgv:1;
/*
* Set if target driver may need to call dma_sync_sg() or similar
* function before transferring cmd' data to the target device
* via DMA.
*/
unsigned int may_need_dma_sync:1;
/* Set if the cmd was done or aborted out of its SN */
unsigned int out_of_sn:1;
/* Set if tgt_sn field is valid */
unsigned int tgt_sn_set:1;
/* Set if any direction residual is possible */
unsigned int resid_possible:1;
/* Set if DIF data should be included in the residual considerations */
unsigned int tgt_dif_data_expected:1;
/* Set if cmd is done */
unsigned int done:1;
/*
* Set if cmd is finished. Used under sess_list_lock to sync
* between scst_finish_cmd() and scst_abort_cmd()
*/
unsigned int finished:1;
/* Set if cmd was pre-alloced by target driver */
unsigned int pre_alloced:1;
/* Set if cmd was already ALUA checked in TRANSITIONING state */
unsigned int already_transitioning:1;
/* Set if scst_cmd_set_write_not_received_data_len() was called */
unsigned int write_not_received_set:1;
/* Set if cmd has LINK bit set in CDB */
unsigned int cmd_linked:1;
/* Set if cmd is on scst_global_stpg_list */
unsigned int cmd_on_global_stpg_list:1;
/* Set if cmd was globally STPG blocked in __scst_check_blocked_dev() */
unsigned int cmd_global_stpg_blocked:1;
/* Set by WRITE VERIFY commands to trigger a verify after write */
unsigned int do_verify:1;
/**************************************************************/
/* cmd's async flags */
unsigned long cmd_flags;
/*
* GFP mask with which memory on READ or WRITE data path for this cmd
* should be allocated, if the current context is not ATOMIC. Useful
* for cases like if this cmd required to not have any IO or FS calls
* on allocations, like for file systems mounted over scst_local's
* devices.
*/
gfp_t cmd_gfp_mask;
/* Keeps status of cmd's status/data delivery to remote initiator */
int delivery_status;
struct scst_tgt_template *tgtt; /* to save extra dereferences */
struct scst_tgt *tgt; /* to save extra dereferences */
struct scst_device *dev; /* to save extra dereferences */
struct scst_dev_type *devt; /* to save extra dereferences */
/* corresponding I_T_L device for this cmd */
struct scst_tgt_dev *tgt_dev;
struct scst_order_data *cur_order_data; /* to save extra dereferences */
uint64_t lun; /* LUN for this cmd */
unsigned long start_time;
ktime_t init_wait_time;
uint64_t init_wait_tsc;
/* List entry for tgt_dev's deferred (SN, ACA, etc.) lists */
struct list_head deferred_cmd_list_entry;
/* Cmd's serial number, used to execute cmd's in order of arrival */
unsigned int sn;
/* The corresponding sn_slot in tgt_dev->sn_slots */
atomic_t *sn_slot;
/* List entry for sess's sess_cmd_list */
struct list_head sess_cmd_list_entry;
/*
* Used to found the cmd by scst_find_cmd_by_tag(). Set by the
* target driver on the cmd's initialization time
*/
uint64_t tag;
uint32_t tgt_sn; /* SN set by target driver (for TM purposes) */
uint8_t *cdb; /* Pointer on CDB. Points on cdb_buf for small CDBs. */
unsigned short cdb_len;
uint8_t cdb_buf[SCST_MAX_CDB_SIZE];
/* List entry for dev's dev_exec_cmd_list */
struct list_head dev_exec_cmd_list_entry;
/*
* Array of blocked by this cmd SCSI atomic cmds with size
* scsi_atomic_blocked_cmds_count. Protected by dev->dev_lock.
*/
struct scst_cmd **scsi_atomic_blocked_cmds;
uint8_t lba_off; /* LBA offset in cdb */
uint8_t lba_len; /* LBA length in cdb */
uint8_t len_off; /* length offset in cdb */
uint8_t len_len; /* length length in cdb */
uint32_t op_flags; /* various flags of this opcode */
const char *op_name; /* op code SCSI full name */
enum scst_cmd_queue_type queue_type;
int timeout; /* CDB execution timeout in seconds */
int retries; /* Amount of retries that will be done by SCSI mid-level */
/*
* Data direction derived from the opcode and the ANSI T10 SCSI specs.
* One of SCST_DATA_* constants.
*/
scst_data_direction data_direction;
/* Values supplied by the initiator in the transport layer header, if any */
scst_data_direction expected_data_direction;
int expected_transfer_len_full; /* both data and DIF tags, if any */
int expected_out_transfer_len; /* for bidi writes */
int64_t lba; /* LBA of this cmd */
/*
* Cmd data length. Could be different from bufflen for commands like
* VERIFY, which transfer different amount of data (if any), than
* processed.
*/
int64_t data_len;
/* Completion routine */
void (*scst_cmd_done)(struct scst_cmd *cmd, int next_state,
enum scst_exec_context pref_context);
struct sgv_pool_obj *sgv; /* data sgv object */
int bufflen; /* cmd buffer length */
int sg_cnt; /* SG segments count */
struct scatterlist *sg; /* cmd data buffer SG vector */
struct sgv_pool_obj *dif_sgv; /* DIF sgv object */
struct scatterlist *dif_sg; /* cmd DIF tags buffer SG vector */
int dif_sg_cnt; /* DIF SG segments count */
/*
* Response data length in data buffer. Must not be set
* directly, use scst_set_resp_data_len() for that.
*/
int resp_data_len;
/*
* Response data length adjusted on residual, i.e.
* min(expected_len, resp_len), if expected len set.
*/
int adjusted_resp_data_len;
/*
* Data length to write, i.e. transfer from the initiator. Might be
* different from (out_)bufflen, if the initiator asked too big or too
* small expected(_out_)transfer_len.
*/
int write_len;
/*
* Write sg and sg_cnt to point out either on sg/sg_cnt, or on
* out_sg/out_sg_cnt.
*/
struct scatterlist **write_sg;
int *write_sg_cnt;
/* scst_get_sg_buf_[first,next]() support */
struct scatterlist *get_sg_buf_cur_sg_entry;
int get_sg_buf_entry_num;
/* Bidirectional transfers support */
int out_bufflen; /* WRITE buffer length */
struct sgv_pool_obj *out_sgv; /* WRITE sgv object */
struct scatterlist *out_sg; /* WRITE data buffer SG vector */
int out_sg_cnt; /* WRITE SG segments count */
/* No out DIF tags buffer, because there's no BIDI command with them */
/*
* Used if both target driver or SCST core for internal commands and
* dev handler request own memory allocation. In other cases, both
* are equal to sg and sg_cnt correspondingly.
*
* If target driver requests own memory allocations, it MUST use
* functions scst_cmd_get_tgt_sg*() to get sg and sg_cnt! Otherwise,
* it may use functions scst_cmd_get_sg*().
*/
struct scatterlist *tgt_i_sg;
int tgt_i_sg_cnt;
int tgt_i_dif_sg_cnt;
struct scatterlist *tgt_i_dif_sg; /* DIF tags */
/*
* There's no tgt_i_dif_sg_cnt, because it's supposed to be strictly
* bound to tgt_i_sg_cnt.
*/
struct scatterlist *tgt_out_sg; /* bidirectional */
int tgt_out_sg_cnt; /* bidirectional */
/* No out DIF tags buffer, because there's no BIDI command with them */
/*
* The status fields in case of errors must be set using
* scst_set_cmd_error_status()!
*/
uint8_t status; /* status byte from target device */
uint8_t msg_status; /* return status from host adapter itself */
uint8_t host_status; /* set by low-level driver to indicate status */
uint8_t driver_status; /* set by mid-level */
/* DIF actions on this cmd */
enum scst_dif_actions cmd_dif_actions;
#ifdef CONFIG_SCST_DIF_INJECT_CORRUPTED_TAGS
uint32_t cmd_corrupt_dif_tag;
#endif
uint8_t *sense; /* pointer to sense buffer */
unsigned short sense_valid_len; /* length of valid sense data */
unsigned short sense_buflen; /* length of the sense buffer, if any */
/* Start time when cmd was sent to rdy_to_xfer() or xmit_response() */
unsigned long hw_pending_start;
/* Used for storage of target driver or internal commands private stuff */
void *tgt_i_priv;
/* Used for storage of dev handler private stuff */
void *dh_priv;
/*
* Number of waiting for this cmd to finish commands
* with SCSI atomic guarantees. Protected by dev->dev_lock.
*/
int scsi_atomic_blockers;
/*
* How many SCSI atomic cmds this cmd blocked, i.e. size of array
* scsi_atomic_blocked_cmds. Protected by dev->dev_lock.
*/
int scsi_atomic_blocked_cmds_count;
/* List entry for dev's blocked_cmd_list */
struct list_head blocked_cmd_list_entry;
/* Used to retry commands in case of double UA */
int dbl_ua_orig_resp_data_len, dbl_ua_orig_data_direction;
/*
* List of the corresponding mgmt cmds, if any. Protected by
* sess_list_lock.
*/
struct list_head mgmt_cmd_list;
/* Used to restore sg if it was modified by scst_adjust_sg*() */
struct scst_orig_sg_data orig_sg, orig_dif_sg;
/* Per opcode stuff */
union {
/* Counter of the corresponding SCST_PR_ABORT_ALL TM commands */
struct scst_pr_abort_all_pending_mgmt_cmds_counter *pr_abort_counter;
/*
* List of parsed data descriptors for commands operating with
* several lba and data_len pairs, like UNMAP, and its size
* in elements.
*/
struct {
void *cmd_data_descriptors;
int cmd_data_descriptors_cnt;
};
/* STPG commands global serialization */
struct {
struct list_head global_stpg_list_entry;
};
};
#if defined(CONFIG_SCST_DEBUG) || defined(CONFIG_SCST_TRACING)
char not_parsed_op_name[8];
#endif
#ifdef CONFIG_SCST_DEBUG_TM
/* Set if the cmd was delayed by task management debugging code */
unsigned int tm_dbg_delayed:1;
/* Set if the cmd must be ignored by task management debugging code */
unsigned int tm_dbg_immut:1;
#endif
};
/*
* Parameters for SCST management commands
*/
struct scst_rx_mgmt_params {
int fn;
uint64_t tag;
const uint8_t *lun;
int lun_len;
uint32_t cmd_sn;
int atomic;
void *tgt_priv;
unsigned char tag_set;
unsigned char lun_set;
unsigned char cmd_sn_set;
};
/*
* A stub structure to link an management command and affected regular commands
*/
struct scst_mgmt_cmd_stub {
struct scst_mgmt_cmd *mcmd;
/* List entry in cmd->mgmt_cmd_list */
struct list_head cmd_mgmt_cmd_list_entry;
/* Set if the cmd was counted in mcmd->cmd_done_wait_count */
unsigned int done_counted:1;
/* Set if the cmd was counted in mcmd->cmd_finish_wait_count */
unsigned int finish_counted:1;
};
/*
* SCST task management structure
*/
struct scst_mgmt_cmd {
/* List entry for *_mgmt_cmd_list */
struct list_head mgmt_cmd_list_entry;
struct scst_session *sess;
atomic_t *cpu_cmd_counter;
/* Mgmt cmd state, one of SCST_MCMD_STATE_* constants */
int state;
int fn; /* task management function */
/* Set if device(s) should be unblocked after mcmd's finish */
unsigned int needs_unblocking:1;
unsigned int lun_set:1; /* set, if lun field is valid */
unsigned int cmd_sn_set:1; /* set, if cmd_sn field is valid */
/* Set if dev handler's task_mgmt_fn_received was called */
unsigned int task_mgmt_fn_received_called:1;
unsigned int mcmd_dropped:1; /* set if mcmd was dropped */
/*
* Number of commands to finish before sending response,
* protected by scst_mcmd_lock
*/
int cmd_finish_wait_count;
/*
* Number of commands to complete (done) before resetting reservation,
* protected by scst_mcmd_lock
*/
int cmd_done_wait_count;
/* Number of completed commands, protected by scst_mcmd_lock */
int completed_cmd_count;
uint64_t lun; /* LUN for this mgmt cmd */
/* or (and for iSCSI) */
uint64_t tag; /* for ABORT TASK, tag of the cmd to abort */
uint32_t cmd_sn; /* affected command's highest SN */
/* corresponding cmd (to be aborted, found by tag) */
struct scst_cmd *cmd_to_abort;
/* corresponding device for this mgmt cmd (found by lun or by tag) */
struct scst_tgt_dev *mcmd_tgt_dev;
/* completion status, one of the SCST_MGMT_STATUS_* constants */
int status;
/* Used for storage of target driver private stuff or origin PR cmd */
union {
void *tgt_priv;
struct scst_cmd *origin_pr_cmd;
};
};
/*
* Persistent reservations registrant
*/
struct scst_dev_registrant {
uint8_t *transport_id;
uint16_t rel_tgt_id;
__be64 key;
/* tgt_dev (I_T nexus) for this registrant, if any */
struct scst_tgt_dev *tgt_dev;
/* List entry for dev_registrants_list */
struct list_head dev_registrants_list_entry;
/* 2 auxiliary fields used to rollback changes for errors, etc. */
struct list_head aux_list_entry;
__be64 rollback_key;
/* For registrant information managed via the DLM. */
int dlm_idx;
struct scst_lksb lksb;
char lvb[PR_DLM_LVB_LEN];
};
/**
* struct scst_cl_ops - Encapsulation of behavior that depends on cluster mode
* @pr_init: Initialize resources needed by one of the functions below.
* @pr_cleanup: Free resources allocated by one of the functions below.
* @pr_is_set: Whether or not one of the registrants holds a reservation.
* @pr_init_reg: Cluster-specific registrant initialization.
* @pr_rm_reg: Cluster-specific registrant cleanup.
* @pr_write_lock: Lock the PR data structures for write access.
* @pr_write_unlock: Unlock the PR data structures for write access.
* @reserved: Whether an initiator holds an SPC-2 reservation.
* @res_lock: Protect the SPC-2 reservation state against concurrent
* modifications.
* @res_unlock: Counterpart of @res_lock.
* @is_rsv_holder: Whether session @sess holds an SPC-2 reservation on @dev.
* @is_not_rsv_holder: Whether another session than @sess holds an SPC-2
* reservation on @dev.
* @reserve: Apply an SPC-2 reservation for session @sess on @dev if
* @sess != NULL or clear that reservation if @ses == NULL.
*/
struct scst_cl_ops {
int (*pr_init)(struct scst_device *dev, const char *cl_dev_id);
void (*pr_cleanup)(struct scst_device *dev);
bool (*pr_is_set)(struct scst_device *dev);
void (*pr_init_reg)(struct scst_device *dev,
struct scst_dev_registrant *reg);
void (*pr_rm_reg)(struct scst_device *dev,
struct scst_dev_registrant *reg);
void (*pr_write_lock)(struct scst_device *dev,
struct scst_lksb *pr_lksb);
void (*pr_write_unlock)(struct scst_device *dev,
struct scst_lksb *pr_lksb);
bool (*reserved)(struct scst_device *dev);
void (*res_lock)(struct scst_device *dev, struct scst_lksb *pr_lksb);
void (*res_unlock)(struct scst_device *dev, struct scst_lksb *pr_lksb);
bool (*is_rsv_holder)(struct scst_device *dev,
struct scst_session *sess);
bool (*is_not_rsv_holder)(struct scst_device *dev,
struct scst_session *sess);
void (*reserve)(struct scst_device *dev, struct scst_session *sess);
};
/*
* Extended, e.g. via sysfs, blockers
*/
typedef void (*ext_blocker_done_fn_t) (struct scst_device *dev,
uint8_t *data, int len);
struct scst_ext_blocker {
struct list_head ext_blockers_list_entry;
ext_blocker_done_fn_t ext_blocker_done_fn;
int ext_blocker_data_len;
uint8_t ext_blocker_data[];
};
/*
* SCST device
*/
struct scst_device {
unsigned int type; /* SCSI type of the device */
/*************************************************************
** Dev's flags. Updates serialized by dev_lock or suspended
** activity
*************************************************************/
/* Set if double reset UA is possible */
unsigned int dev_double_ua_possible:1;
/* If set, dev is read only */
unsigned int dev_rd_only:1;
/* Set, if a strictly serialized cmd is waiting blocked */
unsigned int strictly_serialized_cmd_waiting:1;
/*
* Set if ext blocking is pending. It is just shortcut for
* !list_empty(&dev->ext_blockers_list) to save a cache miss.
*/
unsigned int ext_blocking_pending:1;
/* Used to serialize invocations of __scst_ext_blocking_done() */
unsigned int ext_unblock_scheduled:1;
/* Set if this device was blocked during STPG command processing */
unsigned int stpg_ext_blocked:1;
/* Set if this device does not support DIF IP checking */
unsigned int dev_dif_ip_not_supported:1;
/**************************************************************/
/*************************************************************
** Dev's control mode page related values. Updates serialized
** by device blocking. Since device blocking protects only
** commands on the execution stage, in all other read cases
** use READ_ONCE(), if necessary. Modified independently
** to the above fields, hence the alignment.
*************************************************************/
unsigned int queue_alg:4 __aligned(sizeof(long));
unsigned int tst:3;
unsigned int qerr:2;
unsigned int tmf_only:1;
unsigned int tas:1;
unsigned int swp:1;
unsigned int d_sense:1;
unsigned int dpicz:1;
unsigned int ato:1;
/**
** Saved and default versions of them, which supported. TST is not
** among them, because it's hard to switch curr_order_data on the
** fly. To ensure that no commands lost, we need to flush the previous
** curr_order_data at first and with one being active command (MODE
** SELECT), we don't have facility for that at the moment. Suspending
** activities will hang waiting for the active MODE SELECT. ToDo.
**/
unsigned int queue_alg_saved:4;
unsigned int queue_alg_default:4;
unsigned int tmf_only_saved:1;
unsigned int tmf_only_default:1;
unsigned int qerr_saved:2;
unsigned int qerr_default:2;
unsigned int tas_saved:1;
unsigned int tas_default:1;
unsigned int swp_saved:1;
unsigned int swp_default:1;
unsigned int d_sense_saved:1;
unsigned int d_sense_default:1;
unsigned int dpicz_saved:1;
unsigned int dpicz_default:1;
/*
* Set if device implements own ordered commands management. If not set
* and queue_alg is SCST_QUEUE_ALG_0_RESTRICTED_REORDER, expected_sn
* will be incremented only after commands finished.
*/
unsigned int has_own_order_mgmt:1;
/**************************************************************/
/*
* SCST_DIF_CHECK_APP_TAG (to match usage in the xPROTECT parsing
* routines), if app tag is checked, or 0 otherwise. Might be used
* as bool.
*/
unsigned int dif_app_chk;
/*
* SCST_DIF_CHECK_REF_TAG (to match usage in the xPROTECT parsing
* routines), if ref tag is checked, or 0 otherwise. Might be used
* as bool.
*/
unsigned int dif_ref_chk;
/**************************************************************/
/*
* Device block size and block shift if fixed size blocks used. Supposed
* to be read-only or serialized the same way as MODE pages changes.
*/
int block_size;
int block_shift;
struct scst_dev_type *handler; /* corresponding dev handler */
/* Used for storage of dev handler private stuff */
void *dh_priv;
/* Corresponding real SCSI device, could be NULL for virtual devices */
struct scsi_device *scsi_dev;
/* Device lock */
spinlock_t dev_lock ____cacheline_aligned_in_smp;
#ifdef CONFIG_SCST_PER_DEVICE_CMD_COUNT_LIMIT
/* Number of commands associated with this device. */
atomic_t dev_cmd_count;
#endif
/*
* One more than the number of commands associated with this device
* and the number of SCST data structures holding a reference on this
* data structure.
*/
struct percpu_ref refcnt;
struct work_struct free_work;
struct completion *dev_freed_cmpl;
/*
* Maximum count of uncompleted commands that an initiator could
* queue on this device. Then it will start getting TASK QUEUE FULL
* status.
*/
int max_tgt_dev_commands;
/*
* How many times device was blocked for new cmds execution.
* Protected by dev_lock.
*/
int block_count;
/*
* How many there are "on_dev" commands, i.e. ones who passed
* scst_check_blocked_dev(). Protected by dev_lock.
*/
int on_dev_cmd_count;
/*
* How many atomic SCSI commands being executed. Protected by dev_lock.
*/
int dev_scsi_atomic_cmd_active;
/*
* List of all being executed on the dev commands.
* Protected by dev_lock.
*/
struct list_head dev_exec_cmd_list;
/* Memory limits for this device */
struct scst_mem_lim dev_mem_lim;
/* List of commands with lock, if dedicated threads are used */
struct scst_cmd_threads dev_cmd_threads;
/*************************************************************
** T10-PI fields. Read-only, hence no protection.
*************************************************************/
enum scst_dif_mode dev_dif_mode;
int dev_dif_type; /* SCSI DIF type */
/*
* Callback to process DIF tags by SCST as required by device
* formatting and *protect cmd's bits. Supposed to return 0 on
* success, i.e. when cmd processing should proceed normally, or
* negative error code otherwise, i.e. when cmd processing should
* be stopped and status send to its initiator.
*/
int (*dev_dif_fn)(struct scst_cmd *cmd);
__be16 dev_dif_static_app_tag; /* fixed APP TAG for all blocks in dev */
/*
* Fixed APP TAG part from REF TAG for all blocks in dev. Valid only
* with dif type 3.
*/
__be32 dev_dif_static_app_ref_tag;
/* Cache to optimize scst_parse_*protect() routines */
enum scst_dif_actions dev_dif_rd_actions;
enum scst_dif_actions dev_dif_wr_actions;
enum scst_dif_actions dev_dif_rd_prot0_actions;
enum scst_dif_actions dev_dif_wr_prot0_actions;
enum scst_dif_actions dev_dif_vr_actions;
/* Set if reserved via the SPC-2 SCSI RESERVE command. */
struct scst_session *reserved_by;
/* Operations that depend on whether or not cluster mode is enabled */
const struct scst_cl_ops *cl_ops;
/**********************************************************************
* Persistent reservation fields. Protected as follows:
* - Reading PR data must be protected via scst_pr_read_lock() /
* scst_pr_read_unlock().
* - Modifying PR data modifications must be protected via
* scst_pr_write_lock() / scst_pr_write_unlock().
**********************************************************************/
/*
* Set if dev is persistently reserved. Modified independently
* to the above field, hence the alignment.
*/
unsigned short pr_is_set:1 __aligned(sizeof(long));
/* True if persist through power loss is activated. */
unsigned short pr_aptpl:1;
/* Whether or not pr_file_name has been modified via sysfs. */
unsigned int pr_file_name_is_set:1;
/*
* Whether or not the PR state must be synchronized with other cluster
* nodes.
*/
unsigned int cluster_mode:1;
/* Persistent reservation type */
uint8_t pr_type;
/* Persistent reservation scope */
uint8_t pr_scope;
/* Data structures for managing PR data via the DLM */
struct scst_pr_dlm_data *pr_dlm;
/* Mutex to protect PR operations */
struct mutex dev_pr_mutex;
/* Persistent reservation generation value */
uint32_t pr_generation;
/* Reference to registrant - persistent reservation holder */
struct scst_dev_registrant *pr_holder;
/* List of dev's registrants */
struct list_head dev_registrants_list;
/* End of persistent reservation fields protected by dev_pr_mutex. */
/* NUMA node id of this device, if any (default - NUMA_NO_NODE) */
int dev_numa_node_id;
/*
* Count of connected tgt_devs from transports, which don't support
* PRs, i.e. don't have get_initiator_port_transport_id(). Protected
* by scst_mutex.
*/
int not_pr_supporting_tgt_devs_num;
struct scst_order_data dev_order_data;
/*
* Where to save persistent reservation information. Protected by
* dev_pr_mutex.
*/
char *pr_file_name;
char *pr_file_name1;
/**************************************************************/
/* List of blocked commands, protected by dev_lock. */
struct list_head blocked_cmd_list;
/* Number of ext blocking requests, protected by dev_lock */
int ext_blocks_cnt;
/* List of ext blockers, protected by dev_lock */
struct list_head ext_blockers_list;
/* Work to notify ext blockers out of dev_lock context */
struct work_struct ext_blockers_work;
/* MAXIMUM WRITE SAME LENGTH in bytes */
uint64_t max_write_same_len;
/* A list entry used during TM */
struct list_head tm_dev_list_entry;
int virt_id; /* virtual device internal ID */
/* Pointer to virtual device name, for convenience only */
char *virt_name;
struct list_head dev_list_entry; /* list entry in global devices list */
/*
* List of tgt_dev's, one per session, protected by scst_mutex or
* dev_lock for reads and both for writes
*/
struct list_head dev_tgt_dev_list;
/* List of acg_dev's, one per acg, protected by scst_mutex */
struct list_head dev_acg_dev_list;
/* Number of threads in the device's threads pools */
int threads_num;
/* Threads pool type of the device. Valid only if threads_num > 0. */
enum scst_dev_type_threads_pool_type threads_pool_type;
/* sysfs release completion */
struct completion *dev_kobj_release_cmpl;
struct kobject dev_kobj; /* device sysfs entry */
struct kobject *dev_exp_kobj; /* exported groups */
/* Export number in the dev's sysfs list. Protected by scst_mutex */
int dev_exported_lun_num;
};
/*
* Used to clearly dispose async io_context
*/
struct scst_async_io_context_keeper {
struct kref aic_keeper_kref;
bool aic_ready;
struct io_context *aic;
struct task_struct *aic_keeper_thr;
wait_queue_head_t aic_keeper_waitQ;
};
/*
* Used to store per-session specific device information, analog of
* SCSI I_T_L nexus.
*/
struct scst_tgt_dev {
/* List entry in sess->sess_tgt_dev_list */
struct list_head sess_tgt_dev_list_entry;
struct scst_tgt_template *tgtt; /* to avoid use-after-free issues */
struct scst_device *dev; /* to save extra dereferences */
uint64_t lun; /* to save extra dereferences */
/*
* Extra flags in GFP mask for data buffers allocations of this
* tgt_dev's cmds
*/
gfp_t tgt_dev_gfp_mask;
/* SGV pool from which buffers of this tgt_dev's cmds should be allocated */
struct sgv_pool **pools;
/* Max number of allowed in this tgt_dev SG segments */
int max_sg_cnt;
/*************************************************************
** Flags that control the behavior of a tgt_dev.
*************************************************************/
/* Set if tgt_dev is read only (to save extra dereferences) */
unsigned int tgt_dev_rd_only:1;
/* Set if the corresponding context should be atomic */
unsigned int tgt_dev_after_init_wr_atomic:1;
unsigned int tgt_dev_after_exec_atomic:1;
/* Set if tgt_dev uses clustered SGV pool */
unsigned int tgt_dev_clust_pool:1;
/* Taken from the target on initialization to save a cache miss */
unsigned hw_dif_same_sg_layout_required:1;
/**************************************************************/
/*
* Tgt_dev's async flags. Modified independently to the neighbour
* fields.
*/
unsigned long tgt_dev_flags;
/* Used for storage of dev handler private stuff */
void *dh_priv;
/* Pointer to function to compute DIF guard tag */
__be16 (*tgt_dev_dif_crc_fn)(const void *buffer, unsigned int len);
/*
* Guard tags format, one of SCST_DIF_GUARD_FORMAT_* constants.
* Put here to save extra dereferences, this space isn't used anyway.
*/
int tgt_dev_dif_guard_format;
/* One more than the number of commands associated with this tgt_dev. */
atomic_t tgt_dev_cmd_count ____cacheline_aligned_in_smp;
/* ALUA command filter */
#define SCST_ALUA_CHECK_OK 0
#define SCST_ALUA_CHECK_DELAYED 1
#define SCST_ALUA_CHECK_ERROR -1
int (*alua_filter)(struct scst_cmd *cmd);
struct scst_order_data *curr_order_data;
struct scst_order_data tgt_dev_order_data;
/* Pointer to lists of commands with the lock */
struct scst_cmd_threads *active_cmd_threads;
/* Union to save some CPU cache footprint */
union {
struct {
/* Copy to save fast path dereference */
struct io_context *async_io_context;
struct scst_async_io_context_keeper *aic_keeper;
};
/* Lists of commands with lock, if dedicated threads are used */
struct scst_cmd_threads tgt_dev_cmd_threads;
};
spinlock_t tgt_dev_lock; /* per-session device lock */
/* List of UA's for this device, protected by tgt_dev_lock */
struct list_head UA_list;
struct scst_session *sess; /* corresponding session */
struct scst_acg_dev *acg_dev; /* corresponding acg_dev */
/* Reference to registrant to find quicker */
struct scst_dev_registrant *registrant;
/* List entry in dev->dev_tgt_dev_list */
struct list_head dev_tgt_dev_list_entry;
/* Internal tmp list entry. User must hold scst_mutex. */
struct list_head extra_tgt_dev_list_entry;
/* Set if INQUIRY DATA HAS CHANGED UA is needed */
unsigned int inq_changed_ua_needed:1;
/* How many DIF failures detected on this tgt_dev on the corresponding stage */
atomic_t tgt_dev_dif_app_failed_tgt, tgt_dev_dif_ref_failed_tgt, tgt_dev_dif_guard_failed_tgt;
atomic_t tgt_dev_dif_app_failed_scst, tgt_dev_dif_ref_failed_scst, tgt_dev_dif_guard_failed_scst;
atomic_t tgt_dev_dif_app_failed_dev, tgt_dev_dif_ref_failed_dev, tgt_dev_dif_guard_failed_dev;
/*
* Stored Unit Attention sense and its length for possible
* subsequent REQUEST SENSE. Both protected by tgt_dev_lock.
*/
unsigned short tgt_dev_valid_sense_len;
uint8_t tgt_dev_sense[SCST_SENSE_BUFFERSIZE];
/*
* LUN thread index assigned by scst_add_threads(). Exported via
* sysfs. Can be used to look up which export thread is serving which
* target since this index also appears in the export thread name. Has
* a value in the range 0..n-1 for threads_pool_type per_initiator or
* -1 when using a shared thread pool per LUN or the global thread
* pool.
*/
int thread_index;
/* sysfs release completion */
struct completion *tgt_dev_kobj_release_cmpl;
struct kobject tgt_dev_kobj; /* sessions' LUNs sysfs entry */
};
/*
* Used to store ACG-specific device information, like LUN
*/
struct scst_acg_dev {
struct scst_device *dev; /* corresponding device */
uint64_t lun; /* device's LUN in this acg */
/* If set, the corresponding LU is read only */
unsigned int acg_dev_rd_only:1;
/* Guard tags format, one of SCST_DIF_GUARD_FORMAT_* constants */
int acg_dev_dif_guard_format;
struct scst_acg *acg; /* parent acg */
/* List entry in dev->dev_acg_dev_list */
struct list_head dev_acg_dev_list_entry;
/* List entry in acg->acg_dev_list */
struct list_head acg_dev_list_entry;
struct kobject acg_dev_kobj; /* targets' LUNs sysfs entry */
/* sysfs release completion */
struct completion *acg_dev_kobj_release_cmpl;
/* Name of the link to the corresponding LUN */
char acg_dev_link_name[20];
};
/*
* ACG - access control group. Used to store group related
* control information.
*/
struct scst_acg {
/* One more than the number of sessions in acg_sess_list */
struct kref acg_kref;
/* Owner target */
struct scst_tgt *tgt;
/* List of acg_dev's in this acg, protected by scst_mutex */
struct list_head acg_dev_list;
/* List of attached sessions, protected by scst_mutex */
struct list_head acg_sess_list;
/* List of attached acn's, protected by scst_mutex */
struct list_head acn_list;
/* List entry in tgt_acg_list */
struct list_head acg_list_entry;
/* Name of this acg */
const char *acg_name;
/* Type of I/O initiators grouping */
int acg_io_grouping_type;
/* CPU affinity for threads in this ACG */
cpumask_t acg_cpu_mask;
unsigned int tgt_acg:1;
/* Not a black hole */
#define SCST_ACG_BLACK_HOLE_NONE 0
/* Immediately abort all coming commands */
#define SCST_ACG_BLACK_HOLE_CMD 1
/*
* Immediately abort all coming commands and drop all coming TM commands.
*
* CAUTION! With some target drivers it can cause internal resources
* leaks, so don't abuse this option!
*/
#define SCST_ACG_BLACK_HOLE_ALL 2
/* Immediately abort all coming data transfer commands */
#define SCST_ACG_BLACK_HOLE_DATA_CMD 3
/*
* Immediately abort all coming data transfer commands and drop all
* coming TM commands.
*
* CAUTION! With some target drivers it can cause internal resources
* leaks, so don't abuse this option!
*/
#define SCST_ACG_BLACK_HOLE_DATA_MCMD 4
volatile int acg_black_hole_type;
/* sysfs release completion */
struct completion *acg_kobj_release_cmpl;
struct kobject acg_kobj; /* targets' ini_groups sysfs entry */
struct kobject *luns_kobj;
struct kobject *initiators_kobj;
/* LUNS addressing method for all LUNs in this ACG */
enum scst_lun_addr_method addr_method;
/* Private stuff for target drivers */
void *acg_tgt_priv;
};
/*
* ACN - access control name. Used to store names, by which
* incoming sessions will be assigned to appropriate ACG.
*/
struct scst_acn {
struct scst_acg *acg; /* owner ACG */
const char *name; /* initiator's name */
/* List entry in acg->acn_list */
struct list_head acn_list_entry;
/* sysfs file attributes */
struct kobj_attribute *acn_attr;
};
/**
* struct scst_dev_group - A group of SCST devices (struct scst_device).
* @name: Name of this device group.
* @entry: Entry in scst_dev_group_list.
* @dev_list: List of scst_dg_dev structures; protected by scst_mutex.
* @tg_list: List of scst_target_group structures; protected by scst_mutex.
* @kobj: For making this object visible in sysfs.
* @dev_kobj: Sysfs devices directory.
* @tg_kobj: Sysfs target groups directory.
* @stpg_transport_id Initiator transport ID for STPG originating I_T nexus, if any
* @stpg_rel_tgt_id Relative target ID for STPG originating I_T nexus, if any
*
* Each device is member of zero or one device groups. With each device group
* there are zero or more target groups associated.
*/
struct scst_dev_group {
char *name;
struct list_head entry;
struct list_head dev_list;
struct list_head tg_list;
struct kobject kobj;
struct kobject *dev_kobj;
struct kobject *tg_kobj;
uint8_t *stpg_transport_id;
uint16_t stpg_rel_tgt_id;
};
/**
* struct scst_dg_dev - A node in scst_dev_group.dev_list.
*/
struct scst_dg_dev {
struct list_head entry;
struct scst_device *dev;
};
/**
* struct scst_target_group - A group of SCSI targets (struct scst_tgt).
* @dg: Pointer to the device group that contains this target group.
* @name: Name of this target group.
* @group_id: SPC-4 target port group ID.
* @state: SPC-4 target port group ALUA state.
* @preferred: Value of the SPC-4 target port group PREF attribute.
* @entry: Entry in scst_dev_group.tg_list.
* @tgt_list: list of scst_tg_tgt elements; protected by scst_mutex.
* @kobj: For making this object visible in sysfs.
*
* Such a group is either a primary target port group or a secondary
* port group. See also SPC-4 for more information.
*/
struct scst_target_group {
struct scst_dev_group *dg;
char *name;
uint16_t group_id;
enum scst_tg_state state;
bool preferred;
struct list_head entry;
struct list_head tgt_list;
struct kobject kobj;
};
/**
* struct scst_tg_tgt - A node in scst_target_group.tgt_list.
*
* Such a node can either represent a local storage target (struct scst_tgt)
* or a storage target on another system running SCST. In the former case tgt
* != NULL and rel_tgt_id is ignored. In the latter case tgt == NULL and
* rel_tgt_id is relevant.
*/
struct scst_tg_tgt {
struct list_head entry;
struct scst_target_group *tg;
struct kobject kobj;
struct scst_tgt *tgt;
char *name;
uint16_t rel_tgt_id;
};
/*
* Used to store per-session UNIT ATTENTIONs
*/
struct scst_tgt_dev_UA {
/* List entry in tgt_dev->UA_list */
struct list_head UA_list_entry;
/* Set if UA is global for session */
unsigned short global_UA:1;
/* Unit Attention valid sense len */
unsigned short UA_valid_sense_len;
/* Unit Attention sense buf */
uint8_t UA_sense_buffer[SCST_SENSE_BUFFERSIZE];
};
/* Used to deliver AENs */
struct scst_aen {
int event_fn; /* AEN fn */
struct scst_session *sess; /* corresponding session */
__be64 lun; /* corresponding LUN in SCSI form */
union {
/* SCSI AEN data */
struct {
int aen_sense_len;
uint8_t aen_sense[SCST_STANDARD_SENSE_LEN];
};
};
/* Keeps status of AEN's delivery to remote initiator */
int delivery_status;
};
#define SCST_OD_DEFAULT_CONTROL_BYTE 4 /* NACA */
struct scst_opcode_descriptor {
uint16_t od_serv_action;
uint8_t od_opcode;
uint8_t od_serv_action_valid:1;
uint8_t od_support:3; /* SUPPORT bits */
uint16_t od_cdb_size;
uint8_t od_comm_specific_timeout;
uint32_t od_nominal_timeout;
uint32_t od_recommended_timeout;
uint8_t od_cdb_usage_bits[];
} __packed;
extern const struct scst_opcode_descriptor scst_op_descr_log_select;
extern const struct scst_opcode_descriptor scst_op_descr_log_sense;
extern const struct scst_opcode_descriptor scst_op_descr_mode_select6;
extern const struct scst_opcode_descriptor scst_op_descr_mode_sense6;
extern const struct scst_opcode_descriptor scst_op_descr_mode_select10;
extern const struct scst_opcode_descriptor scst_op_descr_mode_sense10;
extern const struct scst_opcode_descriptor scst_op_descr_rtpg;
extern const struct scst_opcode_descriptor scst_op_descr_stpg;
extern const struct scst_opcode_descriptor scst_op_descr_send_diagnostic;
extern const struct scst_opcode_descriptor scst_op_descr_inquiry;
extern const struct scst_opcode_descriptor scst_op_descr_extended_copy;
extern const struct scst_opcode_descriptor scst_op_descr_tur;
extern const struct scst_opcode_descriptor scst_op_descr_reserve6;
extern const struct scst_opcode_descriptor scst_op_descr_release6;
extern const struct scst_opcode_descriptor scst_op_descr_reserve10;
extern const struct scst_opcode_descriptor scst_op_descr_release10;
extern const struct scst_opcode_descriptor scst_op_descr_pr_in;
extern const struct scst_opcode_descriptor scst_op_descr_pr_out;
extern const struct scst_opcode_descriptor scst_op_descr_report_luns;
extern const struct scst_opcode_descriptor scst_op_descr_request_sense;
extern const struct scst_opcode_descriptor scst_op_descr_report_supp_tm_fns;
extern const struct scst_opcode_descriptor scst_op_descr_report_supp_opcodes;
#define SCST_OPCODE_DESCRIPTORS \
&scst_op_descr_inquiry, \
&scst_op_descr_tur, \
&scst_op_descr_reserve6, \
&scst_op_descr_release6, \
&scst_op_descr_reserve10, \
&scst_op_descr_release10, \
&scst_op_descr_pr_in, \
&scst_op_descr_pr_out, \
&scst_op_descr_report_luns, \
&scst_op_descr_request_sense, \
&scst_op_descr_report_supp_opcodes, \
&scst_op_descr_report_supp_tm_fns,
#ifndef smp_mb__after_set_bit
/* There is no smp_mb__after_set_bit() in the kernel */
#define smp_mb__after_set_bit() smp_mb()
#endif
/*
* Registers target template.
* Returns 0 on success or appropriate error code otherwise.
*/
int __scst_register_target_template(struct scst_tgt_template *vtt,
const char *version);
static inline int scst_register_target_template(struct scst_tgt_template *vtt)
{
return __scst_register_target_template(vtt, SCST_INTERFACE_VERSION);
}
/*
* Registers target template, non-GPL version.
* Returns 0 on success or appropriate error code otherwise.
*
* Note: *vtt must be static!
*/
int __scst_register_target_template_non_gpl(struct scst_tgt_template *vtt,
const char *version);
static inline int scst_register_target_template_non_gpl(
struct scst_tgt_template *vtt)
{
return __scst_register_target_template_non_gpl(vtt,
SCST_INTERFACE_VERSION);
}
void scst_unregister_target_template(struct scst_tgt_template *vtt);
struct scst_tgt *scst_register_target(struct scst_tgt_template *vtt,
const char *target_name);
void scst_unregister_target(struct scst_tgt *tgt);
struct scst_session *scst_register_session(struct scst_tgt *tgt, int atomic,
const char *initiator_name, void *tgt_priv, void *result_fn_data,
void (*result_fn)(struct scst_session *sess, void *data, int result));
struct scst_session *scst_register_session_mq(struct scst_tgt *tgt, int atomic,
const char *initiator_name, void *tgt_priv, void *result_fn_data,
void (*result_fn)(struct scst_session *sess, void *data, int result));
struct scst_session *scst_register_session_non_gpl(struct scst_tgt *tgt,
const char *initiator_name, void *tgt_priv);
void scst_unregister_session(struct scst_session *sess, int wait,
void (*unreg_done_fn)(struct scst_session *sess));
void scst_unregister_session_non_gpl(struct scst_session *sess);
int __scst_register_dev_driver(struct scst_dev_type *dev_type,
const char *version);
static inline int scst_register_dev_driver(struct scst_dev_type *dev_type)
{
return __scst_register_dev_driver(dev_type, SCST_INTERFACE_VERSION);
}
void scst_unregister_dev_driver(struct scst_dev_type *dev_type);
int __scst_register_virtual_dev_driver(struct scst_dev_type *dev_type,
const char *version);
/*
* Registers dev handler driver for virtual devices (eg VDISK).
* Returns 0 on success or appropriate error code otherwise.
*/
static inline int scst_register_virtual_dev_driver(
struct scst_dev_type *dev_type)
{
return __scst_register_virtual_dev_driver(dev_type,
SCST_INTERFACE_VERSION);
}
void scst_unregister_virtual_dev_driver(struct scst_dev_type *dev_type);
bool scst_initiator_has_luns(struct scst_tgt *tgt, const char *initiator_name);
struct scst_cmd *scst_rx_cmd(struct scst_session *sess,
const uint8_t *lun, int lun_len, const uint8_t *cdb,
unsigned int cdb_len, bool atomic);
int scst_rx_cmd_prealloced(struct scst_cmd *cmd, struct scst_session *sess,
const uint8_t *lun, int lun_len, const uint8_t *cdb,
unsigned int cdb_len, bool atomic);
void scst_cmd_init_done(struct scst_cmd *cmd,
enum scst_exec_context pref_context);
/*
* Notifies SCST that the driver finished the first stage of the command
* initialization, and the command is ready for execution, but after
* SCST done the command's preprocessing preprocessing_done() function
* should be called. The second argument sets preferred command execution
* context. See SCST_CONTEXT_* constants for details.
*
* See comment for scst_cmd_init_done() for the serialization requirements.
*/
static inline void scst_cmd_init_stage1_done(struct scst_cmd *cmd,
enum scst_exec_context pref_context, int set_sn)
{
cmd->preprocessing_only = 1;
cmd->set_sn_on_restart_cmd = !set_sn;
scst_cmd_init_done(cmd, pref_context);
}
void scst_restart_cmd(struct scst_cmd *cmd, int status,
enum scst_exec_context pref_context);
void scst_rx_data(struct scst_cmd *cmd, int status,
enum scst_exec_context pref_context);
void scst_tgt_cmd_done(struct scst_cmd *cmd,
enum scst_exec_context pref_context);
int scst_rx_mgmt_fn(struct scst_session *sess,
const struct scst_rx_mgmt_params *params);
static inline void scst_rx_mgmt_params_init(
struct scst_rx_mgmt_params *params)
{
memset(params, 0, sizeof(*params));
}
/*
* Creates new management command using tag and sends it for execution.
* Can be used for SCST_ABORT_TASK only.
* Must not be called in parallel with scst_unregister_session() for the
* same sess. Returns 0 for success, error code otherwise.
*
* Obsolete in favor of scst_rx_mgmt_fn()
*/
static inline int scst_rx_mgmt_fn_tag(struct scst_session *sess, int fn,
uint64_t tag, int atomic, void *tgt_priv)
{
struct scst_rx_mgmt_params params;
BUG_ON(fn != SCST_ABORT_TASK);
scst_rx_mgmt_params_init(&params);
params.fn = fn;
params.tag = tag;
params.tag_set = 1;
params.atomic = atomic;
params.tgt_priv = tgt_priv;
return scst_rx_mgmt_fn(sess, &params);
}
/*
* Creates new management command using LUN and sends it for execution.
* Currently can be used for any fn, except SCST_ABORT_TASK.
* Must not be called in parallel with scst_unregister_session() for the
* same sess. Returns 0 for success, error code otherwise.
*
* Obsolete in favor of scst_rx_mgmt_fn()
*/
static inline int scst_rx_mgmt_fn_lun(struct scst_session *sess, int fn,
const void *lun, int lun_len, int atomic, void *tgt_priv)
{
struct scst_rx_mgmt_params params;
BUG_ON(fn == SCST_ABORT_TASK);
scst_rx_mgmt_params_init(&params);
params.fn = fn;
params.lun = lun;
params.lun_len = lun_len;
params.lun_set = !!lun;
params.atomic = atomic;
params.tgt_priv = tgt_priv;
return scst_rx_mgmt_fn(sess, &params);
}
int scst_get_cdb_info(struct scst_cmd *cmd);
int scst_set_cmd_error_status(struct scst_cmd *cmd, int status);
int scst_set_cmd_error(struct scst_cmd *cmd, int key, int asc, int ascq);
int scst_set_cmd_error_and_inf(struct scst_cmd *cmd, int key, int asc,
int ascq, uint64_t information);
void scst_set_busy(struct scst_cmd *cmd);
void scst_check_convert_sense(struct scst_cmd *cmd);
void scst_set_initial_UA(struct scst_session *sess, int key, int asc, int ascq);
void scst_capacity_data_changed(struct scst_device *dev);
struct scst_cmd *scst_find_cmd_by_tag(struct scst_session *sess, uint64_t tag);
struct scst_cmd *scst_find_cmd(struct scst_session *sess, void *data,
int (*cmp_fn)(struct scst_cmd *cmd,
void *data));
enum dma_data_direction scst_to_dma_dir(int scst_dir);
enum dma_data_direction scst_to_tgt_dma_dir(int scst_dir);
int scst_register_virtual_device_node(struct scst_dev_type *dev_handler,
const char *dev_name, int nodeid);
static inline int scst_register_virtual_device(struct scst_dev_type *dev_handler,
const char *dev_name)
{
return scst_register_virtual_device_node(dev_handler, dev_name,
NUMA_NO_NODE);
}
void scst_unregister_virtual_device(int id,
void (*on_free)(struct scst_device *dev,
void *arg),
void *arg);
/*
* Get/Set functions for tgt's sg_tablesize
*/
static inline int scst_tgt_get_sg_tablesize(struct scst_tgt *tgt)
{
return tgt->sg_tablesize;
}
static inline void scst_tgt_set_sg_tablesize(struct scst_tgt *tgt, int val)
{
tgt->sg_tablesize = val;
}
/*
* Get/Set functions for tgt's target private data
*/
static inline void *scst_tgt_get_tgt_priv(struct scst_tgt *tgt)
{
return tgt->tgt_priv;
}
static inline void scst_tgt_set_tgt_priv(struct scst_tgt *tgt, void *val)
{
tgt->tgt_priv = val;
}
/*
* Get/Set functions for tgt's tgt_dif_supported
*/
static inline bool scst_tgt_get_dif_supported(struct scst_tgt *tgt)
{
return tgt->tgt_dif_supported;
}
static inline void scst_tgt_set_dif_supported(struct scst_tgt *tgt, bool val)
{
tgt->tgt_dif_supported = !!val;
}
/*
* Get/Set functions for tgt's tgt_hw_dif_type1_supported
*/
static inline bool scst_tgt_get_hw_dif_type1_supported(struct scst_tgt *tgt)
{
return tgt->tgt_hw_dif_type1_supported;
}
static inline void scst_tgt_set_hw_dif_type1_supported(struct scst_tgt *tgt, bool val)
{
tgt->tgt_hw_dif_type1_supported = !!val;
}
/*
* Get/Set functions for tgt's tgt_hw_dif_type2_supported
*/
static inline bool scst_tgt_get_hw_dif_type2_supported(struct scst_tgt *tgt)
{
return tgt->tgt_hw_dif_type2_supported;
}
static inline void scst_tgt_set_hw_dif_type2_supported(struct scst_tgt *tgt, bool val)
{
tgt->tgt_hw_dif_type2_supported = !!val;
}
/*
* Get/Set functions for tgt's tgt_hw_dif_type3_supported
*/
static inline bool scst_tgt_get_hw_dif_type3_supported(struct scst_tgt *tgt)
{
return tgt->tgt_hw_dif_type3_supported;
}
static inline void scst_tgt_set_hw_dif_type3_supported(struct scst_tgt *tgt, bool val)
{
tgt->tgt_hw_dif_type3_supported = !!val;
}
/*
* Get/Set functions for tgt's tgt_hw_dif_ip_supported
*/
static inline bool scst_tgt_get_hw_dif_ip_supported(struct scst_tgt *tgt)
{
return tgt->tgt_hw_dif_ip_supported;
}
static inline void scst_tgt_set_hw_dif_ip_supported(struct scst_tgt *tgt, bool val)
{
tgt->tgt_hw_dif_ip_supported = !!val;
}
/*
* Get/Set functions for tgt's tgt_hw_dif_same_sg_layout_required
*/
static inline bool scst_tgt_get_hw_dif_same_sg_layout_required(struct scst_tgt *tgt)
{
return tgt->tgt_hw_dif_same_sg_layout_required;
}
static inline void scst_tgt_set_hw_dif_same_sg_layout_required(struct scst_tgt *tgt, bool val)
{
tgt->tgt_hw_dif_same_sg_layout_required = !!val;
}
/*
* Get/Set functions for tgt's tgt_supported_dif_block_sizes
*/
static inline const int *scst_tgt_get_supported_dif_block_sizes(
struct scst_tgt *tgt)
{
return tgt->tgt_supported_dif_block_sizes;
}
static inline void scst_tgt_set_supported_dif_block_sizes(struct scst_tgt *tgt,
const int *const val)
{
tgt->tgt_supported_dif_block_sizes = val;
}
void scst_update_hw_pending_start(struct scst_cmd *cmd);
/*
* Get/Set functions for session's target private data
*/
static inline void *scst_sess_get_tgt_priv(struct scst_session *sess)
{
return sess->sess_tgt_priv;
}
static inline void scst_sess_set_tgt_priv(struct scst_session *sess,
void *val)
{
sess->sess_tgt_priv = val;
}
uint16_t scst_lookup_tg_id(struct scst_device *dev, struct scst_tgt *tgt);
enum scst_tg_state scst_get_alua_state(struct scst_device *dev, struct scst_tgt *tgt);
bool scst_alua_configured(struct scst_device *dev);
int scst_tg_get_group_info(void **buf, uint32_t *response_length,
struct scst_device *dev, uint8_t data_format);
int scst_tg_set_group_info(struct scst_cmd *cmd);
const char *scst_alua_state_name(enum scst_tg_state s);
void scst_stpg_del_unblock_next(struct scst_cmd *cmd);
/*
* Get/set functions for dev's static DIF APP TAG
*/
static inline __be16 scst_dev_get_dif_static_app_tag(struct scst_device *dev)
{
return dev->dev_dif_static_app_tag;
}
static inline __be32 scst_dev_get_dif_static_app_ref_tag(struct scst_device *dev)
{
return dev->dev_dif_static_app_ref_tag;
}
static inline __be64 scst_dev_get_dif_static_app_tag_combined(
struct scst_device *dev)
{
uint64_t a = (((uint64_t)be32_to_cpu(dev->dev_dif_static_app_ref_tag)) << 16) |
be16_to_cpu(dev->dev_dif_static_app_tag);
return cpu_to_be64(a);
}
void scst_dev_set_dif_static_app_tag_combined(struct scst_device *dev,
__be64 app_tag);
/*
* Get/set functions for dev's DIF APP TAG checking
*/
static inline bool scst_dev_get_dif_app_tag_check(struct scst_device *dev)
{
return dev->dif_app_chk == SCST_DIF_CHECK_APP_TAG;
}
int scst_set_dif_params(struct scst_device *dev,
enum scst_dif_mode dif_mode, int dif_type);
/*
* Functions to account detected DIF errors on the corresponding stages
*/
static inline void scst_dif_acc_app_check_failed_tgt(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_app_failed_tgt);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_app_failed_tgt);
}
static inline void scst_dif_acc_ref_check_failed_tgt(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_ref_failed_tgt);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_ref_failed_tgt);
}
static inline void scst_dif_acc_guard_check_failed_tgt(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_guard_failed_tgt);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_guard_failed_tgt);
}
static inline void scst_dif_acc_app_check_failed_scst(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_app_failed_scst);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_app_failed_scst);
}
static inline void scst_dif_acc_ref_check_failed_scst(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_ref_failed_scst);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_ref_failed_scst);
}
static inline void scst_dif_acc_guard_check_failed_scst(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_guard_failed_scst);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_guard_failed_scst);
}
static inline void scst_dif_acc_app_check_failed_dev(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_app_failed_dev);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_app_failed_dev);
}
static inline void scst_dif_acc_ref_check_failed_dev(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_ref_failed_dev);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_ref_failed_dev);
}
static inline void scst_dif_acc_guard_check_failed_(struct scst_cmd *cmd)
{
atomic_inc(&cmd->tgt->tgt_dif_guard_failed_dev);
atomic_inc(&cmd->tgt_dev->tgt_dev_dif_guard_failed_dev);
}
/*
* Functions to process DIF tags by SCST as required by device
* formatting and *protect cmd's bits.
*
* Return 0 on success, i.e. when cmd processing should proceed normally,
* or negative error code otherwise, i.e. when cmd processing should be
* stopped and status send to its initiator.
*/
static inline int scst_dif_process_read(struct scst_cmd *cmd)
{
return cmd->dev->dev_dif_fn(cmd);
}
static inline int scst_dif_process_write(struct scst_cmd *cmd)
{
return cmd->dev->dev_dif_fn(cmd);
}
/**
* Returns TRUE if cmd is being executed in atomic context.
*
* This function must be used outside of spinlocks and preempt/BH/IRQ
* disabled sections, because of the EXTRACHECK in it.
*/
static inline bool scst_cmd_atomic(struct scst_cmd *cmd)
{
int res = cmd->atomic;
#ifdef CONFIG_SCST_EXTRACHECKS
/*
* Checkpatch will complain on the use of in_atomic() below. You
* can safely ignore this warning since in_atomic() is used here
* only for debugging purposes.
*/
if (unlikely((in_atomic() || in_interrupt() || irqs_disabled()) &&
!res)) {
pr_err("ERROR: atomic context and non-atomic cmd!\n");
dump_stack();
cmd->atomic = 1;
res = 1;
}
#endif
return res;
}
/* Returns TRUE if cmd completed with SAM_STAT_GOOD */
static inline bool scst_cmd_completed_good(struct scst_cmd *cmd)
{
return cmd->completed && (cmd->status == SAM_STAT_GOOD);
}
/*
* Returns TRUE if cmd has been preliminary completed, i.e. completed or
* aborted.
*/
static inline bool scst_cmd_prelim_completed(struct scst_cmd *cmd)
{
return cmd->completed || test_bit(SCST_CMD_ABORTED, &cmd->cmd_flags);
}
static inline enum scst_exec_context __scst_estimate_context(bool atomic)
{
if (in_irq())
return SCST_CONTEXT_TASKLET;
/*
* We come here from many non reliable places, like the block layer, and don't
* have any reliable way to detect if we called under atomic context or not
* (in_atomic() isn't reliable), so let's be safe and disable this section
* for now to unconditionally return thread context.
*/
#if 0
else if (irqs_disabled())
return SCST_CONTEXT_THREAD;
else if (in_atomic())
return SCST_CONTEXT_DIRECT_ATOMIC;
else
return atomic ? SCST_CONTEXT_DIRECT_ATOMIC :
SCST_CONTEXT_DIRECT;
#else
return SCST_CONTEXT_THREAD;
#endif
}
static inline enum scst_exec_context scst_estimate_context(void)
{
return __scst_estimate_context(false);
}
static inline enum scst_exec_context scst_estimate_context_atomic(void)
{
return __scst_estimate_context(true);
}
/* Returns cmd's CDB */
static inline const uint8_t *scst_cmd_get_cdb(struct scst_cmd *cmd)
{
return cmd->cdb;
}
/* Returns cmd's CDB length */
static inline unsigned int scst_cmd_get_cdb_len(struct scst_cmd *cmd)
{
return cmd->cdb_len;
}
void scst_cmd_set_ext_cdb(struct scst_cmd *cmd,
uint8_t *ext_cdb, unsigned int ext_cdb_len, gfp_t gfp_mask);
/* Returns cmd's session */
static inline struct scst_session *scst_cmd_get_session(struct scst_cmd *cmd)
{
return cmd->sess;
}
/* Returns cmd's response data length */
static inline int scst_cmd_get_resp_data_len(struct scst_cmd *cmd)
{
return cmd->resp_data_len;
}
/* Returns cmd's adjusted response data length */
static inline int scst_cmd_get_adjusted_resp_data_len(struct scst_cmd *cmd)
{
return cmd->adjusted_resp_data_len;
}
/* Returns if status should be sent for cmd */
static inline int scst_cmd_get_is_send_status(struct scst_cmd *cmd)
{
return cmd->is_send_status;
}
/*
* Returns pointer to cmd's SG data buffer.
*
* Usage of this function is not recommended, use scst_get_buf_*()
* family of functions instead.
*/
static inline struct scatterlist *scst_cmd_get_sg(struct scst_cmd *cmd)
{
return cmd->sg;
}
/*
* Returns cmd's sg_cnt.
*
* Usage of this function is not recommended, use scst_get_buf_*()
* family of functions instead.
*/
static inline int scst_cmd_get_sg_cnt(struct scst_cmd *cmd)
{
return cmd->sg_cnt;
}
/*
* Returns pointer to cmd's DIF tags SG data buffer.
*
* Usage of this function is not recommended, use scst_get_dif_buf()
* function instead.
*/
static inline struct scatterlist *scst_cmd_get_dif_sg(struct scst_cmd *cmd)
{
return cmd->dif_sg;
}
/*
* Returns pointer to cmd's DIF tags SG data buffer elements count.
*
* Usage of this function is not recommended, use scst_get_dif_buf()
* function instead.
*/
static inline int scst_cmd_get_dif_sg_cnt(struct scst_cmd *cmd)
{
return cmd->dif_sg_cnt;
}
/* Returns cmd's LBA */
static inline int64_t scst_cmd_get_lba(struct scst_cmd *cmd)
{
return cmd->lba;
}
/*
* Returns cmd's data buffer length.
*
* In case if you need to iterate over data in the buffer, usage of
* this function is not recommended, use scst_get_buf_*()
* family of functions instead.
*/
static inline int scst_cmd_get_bufflen(struct scst_cmd *cmd)
{
return cmd->bufflen;
}
/*
* Returns cmd's data_len. See the corresponding field's description in
* struct scst_cmd above.
*/
static inline int64_t scst_cmd_get_data_len(struct scst_cmd *cmd)
{
return cmd->data_len;
}
/* Returns true, if cmd needs DIF buffer */
static inline bool scst_cmd_needs_dif_buf(struct scst_cmd *cmd)
{
return (scst_get_dif_action(scst_get_scst_dif_actions(cmd->cmd_dif_actions)) != SCST_DIF_ACTION_NONE) ||
(scst_get_dif_action(scst_get_dev_dif_actions(cmd->cmd_dif_actions)) != SCST_DIF_ACTION_NONE);
}
/* Returns length of DIF buffer of this cmd */
static inline int __scst_cmd_get_bufflen_dif(struct scst_cmd *cmd)
{
return (cmd->bufflen >> cmd->dev->block_shift) << SCST_DIF_TAG_SHIFT;
}
static inline int scst_cmd_get_bufflen_dif(struct scst_cmd *cmd)
{
if (scst_cmd_needs_dif_buf(cmd))
return __scst_cmd_get_bufflen_dif(cmd);
else
return 0;
}
/*
* Returns pointer to cmd's bidirectional in (WRITE) SG data buffer.
*
* Usage of this function is not recommended, use scst_get_out_buf_*()
* family of functions instead.
*/
static inline struct scatterlist *scst_cmd_get_out_sg(struct scst_cmd *cmd)
{
return cmd->out_sg;
}
/*
* Returns cmd's bidirectional in (WRITE) sg_cnt.
*
* Usage of this function is not recommended, use scst_get_out_buf_*()
* family of functions instead.
*/
static inline int scst_cmd_get_out_sg_cnt(struct scst_cmd *cmd)
{
return cmd->out_sg_cnt;
}
void scst_restore_sg_buff(struct scst_cmd *cmd);
/* Restores modified sg buffer in the original state, if necessary */
static inline void scst_check_restore_sg_buff(struct scst_cmd *cmd)
{
if (unlikely(cmd->sg_buff_modified || cmd->dif_sg_buff_modified))
scst_restore_sg_buff(cmd);
}
/*
* Returns cmd's bidirectional in (WRITE) data buffer length.
*
* In case if you need to iterate over data in the buffer, usage of
* this function is not recommended, use scst_get_out_buf_*()
* family of functions instead.
*/
static inline unsigned int scst_cmd_get_out_bufflen(struct scst_cmd *cmd)
{
return cmd->out_bufflen;
}
/*
* Returns pointer to cmd's target's SG data buffer. Since it's for target
* drivers, the "_i_" part is omitted.
*/
static inline struct scatterlist *scst_cmd_get_tgt_sg(struct scst_cmd *cmd)
{
return cmd->tgt_i_sg;
}
/*
* Returns cmd's target's sg_cnt. Since it's for target
* drivers, the "_i_" part is omitted.
*/
static inline int scst_cmd_get_tgt_sg_cnt(struct scst_cmd *cmd)
{
return cmd->tgt_i_sg_cnt;
}
/*
* Sets cmd's target's SG data buffer. Since it's for target
* drivers, the "_i_" part is omitted.
*/
static inline void scst_cmd_set_tgt_sg(struct scst_cmd *cmd,
struct scatterlist *sg, int sg_cnt)
{
cmd->tgt_i_sg = sg;
cmd->tgt_i_sg_cnt = sg_cnt;
cmd->tgt_i_data_buf_alloced = 1;
}
/*
* Returns pointer to cmd's target's DIF tags SG data buffer. Since it's
* for target drivers, the "_i_" part is omitted.
*/
static inline struct scatterlist *scst_cmd_get_tgt_dif_sg(struct scst_cmd *cmd)
{
return cmd->tgt_i_dif_sg;
}
/*
* Returns cmd's target's DIF tags SG data buffer elements count. Since it's
* for target drivers, the "_i_" part is omitted.
*/
static inline int scst_cmd_get_tgt_dif_sg_cnt(struct scst_cmd *cmd)
{
return cmd->tgt_i_dif_sg_cnt;
}
/*
* Sets cmd's target's DIF tags SG data buffer. Since it's for target
* drivers, the "_i_" part is omitted.
*/
static inline void scst_cmd_set_tgt_dif_sg(struct scst_cmd *cmd,
struct scatterlist *dif_sg, int cnt)
{
cmd->tgt_i_dif_sg = dif_sg;
cmd->tgt_i_dif_sg_cnt = cnt;
}
/* Returns pointer to cmd's target's OUT SG data buffer */
static inline struct scatterlist *scst_cmd_get_out_tgt_sg(struct scst_cmd *cmd)
{
return cmd->tgt_out_sg;
}
/* Returns cmd's target's OUT sg_cnt */
static inline int scst_cmd_get_tgt_out_sg_cnt(struct scst_cmd *cmd)
{
return cmd->tgt_out_sg_cnt;
}
/* Sets cmd's target's OUT SG data buffer */
static inline void scst_cmd_set_tgt_out_sg(struct scst_cmd *cmd,
struct scatterlist *sg, int sg_cnt)
{
WARN_ON(!cmd->tgt_i_data_buf_alloced);
cmd->tgt_out_sg = sg;
cmd->tgt_out_sg_cnt = sg_cnt;
}
/* Returns cmd's data direction */
static inline scst_data_direction scst_cmd_get_data_direction(
struct scst_cmd *cmd)
{
return cmd->data_direction;
}
/* Returns cmd's write len as well as write SG and sg_cnt */
static inline int scst_cmd_get_write_fields(struct scst_cmd *cmd,
struct scatterlist **sg, int *sg_cnt)
{
*sg = *cmd->write_sg;
*sg_cnt = *cmd->write_sg_cnt;
return cmd->write_len;
}
void scst_cmd_set_write_not_received_data_len(struct scst_cmd *cmd,
int not_received);
bool __scst_get_resid(struct scst_cmd *cmd, int *resid, int *bidi_out_resid);
/*
* Returns true if cmd has residual(s) and returns them in the corresponding
* parameters(s).
*/
static inline bool scst_get_resid(struct scst_cmd *cmd,
int *resid, int *bidi_out_resid)
{
if (likely(!cmd->resid_possible))
return false;
return __scst_get_resid(cmd, resid, bidi_out_resid);
}
/* Returns cmd's status byte from host device */
static inline uint8_t scst_cmd_get_status(struct scst_cmd *cmd)
{
return cmd->status;
}
/* Returns cmd's status from host adapter itself */
static inline uint8_t scst_cmd_get_msg_status(struct scst_cmd *cmd)
{
return cmd->msg_status;
}
/* Returns cmd's status set by low-level driver to indicate its status */
static inline uint8_t scst_cmd_get_host_status(struct scst_cmd *cmd)
{
return cmd->host_status;
}
/* Returns cmd's status set by SCSI mid-level */
static inline uint8_t scst_cmd_get_driver_status(struct scst_cmd *cmd)
{
return cmd->driver_status;
}
/* Returns pointer to cmd's sense buffer */
static inline uint8_t *scst_cmd_get_sense_buffer(struct scst_cmd *cmd)
{
return cmd->sense;
}
/* Returns cmd's valid sense length */
static inline int scst_cmd_get_sense_buffer_len(struct scst_cmd *cmd)
{
return cmd->sense_valid_len;
}
/*
* Get/Set functions for cmd's queue_type
*/
static inline enum scst_cmd_queue_type scst_cmd_get_queue_type(
struct scst_cmd *cmd)
{
return cmd->queue_type;
}
static inline void scst_cmd_set_queue_type(struct scst_cmd *cmd,
enum scst_cmd_queue_type queue_type)
{
cmd->queue_type = queue_type;
}
/*
* Get/Set functions for cmd's target SN
*/
static inline uint64_t scst_cmd_get_tag(struct scst_cmd *cmd)
{
return cmd->tag;
}
static inline void scst_cmd_set_tag(struct scst_cmd *cmd, uint64_t tag)
{
cmd->tag = tag;
}
/*
* Get/Set functions for cmd's target private data.
* Variant with *_lock must be used if target driver uses
* scst_find_cmd() to avoid race with it, except inside scst_find_cmd()'s
* callback, where lock is already taken.
*/
static inline void *scst_cmd_get_tgt_priv(struct scst_cmd *cmd)
{
return cmd->tgt_i_priv;
}
static inline void scst_cmd_set_tgt_priv(struct scst_cmd *cmd, void *val)
{
cmd->tgt_i_priv = val;
}
/*
* Get/Set functions for tgt_need_alloc_data_buf flag
*/
static inline int scst_cmd_get_tgt_need_alloc_data_buf(struct scst_cmd *cmd)
{
return cmd->tgt_need_alloc_data_buf;
}
static inline void scst_cmd_set_tgt_need_alloc_data_buf(struct scst_cmd *cmd)
{
cmd->tgt_need_alloc_data_buf = 1;
}
/*
* Get/Set functions for tgt_i_data_buf_alloced flag. Since they are for target
* drivers, the "_i_" part is omitted.
*/
static inline int scst_cmd_get_tgt_data_buff_alloced(struct scst_cmd *cmd)
{
return cmd->tgt_i_data_buf_alloced;
}
static inline void scst_cmd_set_tgt_data_buff_alloced(struct scst_cmd *cmd)
{
cmd->tgt_i_data_buf_alloced = 1;
}
/*
* Get/Set functions for dh_data_buf_alloced flag
*/
static inline int scst_cmd_get_dh_data_buff_alloced(struct scst_cmd *cmd)
{
return cmd->dh_data_buf_alloced;
}
static inline void scst_cmd_set_dh_data_buff_alloced(struct scst_cmd *cmd)
{
cmd->dh_data_buf_alloced = 1;
}
/*
* Get/Set functions for no_sgv flag
*/
static inline int scst_cmd_get_no_sgv(struct scst_cmd *cmd)
{
return cmd->no_sgv;
}
static inline void scst_cmd_set_no_sgv(struct scst_cmd *cmd)
{
cmd->no_sgv = 1;
}
/*
* Get/Set functions for tgt_sn
*/
static inline int scst_cmd_get_tgt_sn(struct scst_cmd *cmd)
{
BUG_ON(!cmd->tgt_sn_set);
return cmd->tgt_sn;
}
static inline void scst_cmd_set_tgt_sn(struct scst_cmd *cmd, uint32_t tgt_sn)
{
cmd->tgt_sn_set = 1;
cmd->tgt_sn = tgt_sn;
}
/*
* Forbids for this cmd any IO-causing allocations.
*
* !! Must be called before scst_cmd_init_done() !!
*/
static inline void scst_cmd_set_noio_mem_alloc(struct scst_cmd *cmd)
{
cmd->cmd_gfp_mask = GFP_NOIO;
}
/*
* Returns true if the cmd was aborted, so the caller should complete it as
* soon as possible.
*
* !! Xmit_response() callback must use scst_cmd_aborted_on_xmit() instead !!
* !! to allow status of completed commands aborted by other initiators be !!
* !! delivered to their initiators !!
*/
static inline bool scst_cmd_aborted(struct scst_cmd *cmd)
{
return test_bit(SCST_CMD_ABORTED, &cmd->cmd_flags);
}
/*
* Returns true if the cmd was aborted by its initiator or aborted by another
* initiator and not completed, so its status is invalid and no reply shall
* be sent to the remote initiator. A target driver should only clear
* internal resources, associated with cmd.
*
* This functions shall be called by all target drivers in the beginning of
* xmit_response() callback.
*/
static inline bool scst_cmd_aborted_on_xmit(struct scst_cmd *cmd)
{
return test_bit(SCST_CMD_ABORTED, &cmd->cmd_flags) &&
!test_bit(SCST_CMD_ABORTED_OTHER, &cmd->cmd_flags);
}
/* Returns sense data format for cmd's dev */
static inline bool scst_get_cmd_dev_d_sense(struct scst_cmd *cmd)
{
return (cmd->dev != NULL) ? cmd->dev->d_sense : 0;
}
/*
* Get/Set functions for expected data direction, transfer length
* and its validity flag
*/
static inline int scst_cmd_is_expected_set(struct scst_cmd *cmd)
{
return cmd->expected_values_set;
}
static inline scst_data_direction scst_cmd_get_expected_data_direction(
struct scst_cmd *cmd)
{
return cmd->expected_data_direction;
}
/*
* Returns full expected transfer length, i.e. including both data and
* DIF tags, if any.
*/
static inline int scst_cmd_get_expected_transfer_len_full(
struct scst_cmd *cmd)
{
return cmd->expected_transfer_len_full;
}
int scst_cmd_get_expected_transfer_len_data(struct scst_cmd *cmd);
int scst_cmd_get_expected_transfer_len_dif(struct scst_cmd *cmd);
static inline int scst_cmd_get_expected_out_transfer_len(
struct scst_cmd *cmd)
{
return cmd->expected_out_transfer_len;
}
static inline void scst_cmd_set_expected(struct scst_cmd *cmd,
scst_data_direction expected_data_direction,
int expected_transfer_len_full)
{
cmd->expected_data_direction = expected_data_direction;
cmd->expected_transfer_len_full = expected_transfer_len_full;
cmd->expected_values_set = 1;
}
static inline void scst_cmd_set_expected_out_transfer_len(struct scst_cmd *cmd,
int expected_out_transfer_len)
{
WARN_ON(!cmd->expected_values_set);
cmd->expected_out_transfer_len = expected_out_transfer_len;
}
/*
* Get/clear functions for cmd's may_need_dma_sync
*/
static inline int scst_get_may_need_dma_sync(struct scst_cmd *cmd)
{
return cmd->may_need_dma_sync;
}
static inline void scst_clear_may_need_dma_sync(struct scst_cmd *cmd)
{
cmd->may_need_dma_sync = 0;
}
/*
* Get/set functions for cmd's delivery_status. It is one of
* SCST_CMD_DELIVERY_* constants. It specifies the status of the
* command's delivery to initiator.
*/
static inline int scst_get_delivery_status(struct scst_cmd *cmd)
{
return cmd->delivery_status;
}
static inline void scst_set_delivery_status(struct scst_cmd *cmd,
int delivery_status)
{
cmd->delivery_status = delivery_status;
}
/*
* Returns T10-PI actions, including checks, which target driver should do
* with this command on READ direction transfers (xmit_response()). Might
* be different from WRITE direction for BIDI commands.
*/
static inline enum scst_dif_actions scst_get_read_dif_tgt_actions(
struct scst_cmd *cmd)
{
return scst_get_tgt_dif_actions(cmd->cmd_dif_actions);
}
/*
* Returns T10-PI actions, including checks, which target driver should do
* with this command on WRITE direction transfers (rdy_to_xfer()). Might
* be different from READ direction for BIDI commands.
*/
static inline enum scst_dif_actions scst_get_write_dif_tgt_actions(
struct scst_cmd *cmd)
{
return scst_get_tgt_dif_actions(cmd->cmd_dif_actions);
}
/*
* Returns T10-PI actions, including checks, which dev handler should do
* with this command on READ direction transfers. Might be different
* from WRITE direction for BIDI commands.
*/
static inline enum scst_dif_actions scst_get_read_dif_dev_actions(
struct scst_cmd *cmd)
{
return scst_get_dev_dif_actions(cmd->cmd_dif_actions);
}
/*
* Returns T10-PI actions, including checks, which dev handler should do
* with this command on WRITE direction transfers. Might be different
* from READ direction for BIDI commands.
*/
static inline enum scst_dif_actions scst_get_write_dif_dev_actions(
struct scst_cmd *cmd)
{
return scst_get_dev_dif_actions(cmd->cmd_dif_actions);
}
/*
* Returns T10-PI protection type for this cmd's device. Supposed to be used
* by target drivers.
*/
static inline int scst_cmd_get_dif_prot_type(struct scst_cmd *cmd)
{
return cmd->dev->dev_dif_type;
}
/*
* Returns T10-PI application tag for this cmd's device's lba.
*
* If SCST_DIF_NO_CHECK_APP_TAG returned, the target driver should not
* check app tag for this lba (SCSI requirement).
*
* Parameter out_lba_end returns end LBA of the area, where this app tag
* is valid. Then, if necessary, the target driver supposed to call
* this function again for the next app tag area. This is intended to
* support Application Tag mode page. ToDo, not implemented yet.
*/
static inline __be16 scst_cmd_get_dif_app_tag(struct scst_cmd *cmd,
uint64_t lba_start/*, uint64_t *out_lba_end*/)
{
#ifdef CONFIG_SCST_EXTRACHECKS
WARN_ON(!(scst_get_dif_checks(cmd->cmd_dif_actions) & SCST_DIF_CHECK_APP_TAG));
#endif
return cmd->dev->dev_dif_static_app_tag;
}
/*
* Returns T10-PI type 2 expected initial reference tag as LBA, i.e. converted
* into CPU endianness. Valid only with protection type 2.
*/
static inline uint32_t scst_cmd_get_dif_exp_ref_tag(struct scst_cmd *cmd)
{
#ifdef CONFIG_SCST_EXTRACHECKS
BUG_ON(cmd->dev->dev_dif_type != 2);
WARN_ON(cmd->cdb_len > 32);
#endif
if (cmd->cdb_len == 32)
return get_unaligned_be32(&cmd->cdb[20]);
else
return cmd->lba & 0xFFFFFFFF;
}
/*
* Returns T10-PI type 2 expected logical block application tag converted
* into CPU endianness. Valid only with protection type 2.
*/
static inline uint16_t scst_cmd_get_dif_exp_app_tag(struct scst_cmd *cmd)
{
#ifdef CONFIG_SCST_EXTRACHECKS
BUG_ON(cmd->dev->dev_dif_type != 2);
WARN_ON(cmd->cdb_len > 32);
#endif
if (cmd->cdb_len == 32)
return get_unaligned_be16(&cmd->cdb[24]);
else {
/* cmd->dev must be alive at this point */
return be16_to_cpu(cmd->dev->dev_dif_static_app_tag);
}
}
/*
* Returns T10-PI type 2 logical block application tag mask converted
* into CPU endianness. Valid only with protection type 2.
*/
static inline uint16_t scst_cmd_get_dif_app_tag_mask(struct scst_cmd *cmd)
{
#ifdef CONFIG_SCST_EXTRACHECKS
BUG_ON(cmd->dev->dev_dif_type != 2);
WARN_ON(cmd->cdb_len > 32);
#endif
if (cmd->cdb_len == 32)
return get_unaligned_be16(&cmd->cdb[26]);
else {
if (scst_get_dif_checks(cmd->cmd_dif_actions) & SCST_DIF_CHECK_APP_TAG)
return 0xFFFF;
else
return 0;
}
}
/*
* Returns T10-PI type 3 application/reference tag. Valid only with type 3
* protection type. Alternatively, scst_dev_get_dif_static_app_tag_combined()
* can be used.
*
* If SCST_DIF_NO_CHECK_ALL_REF_TAG returned, the target driver should not
* check the tag for this lba (SCSI requirement).
*/
static inline __be32 scst_cmd_get_dif_app_ref_tag(struct scst_cmd *cmd)
{
#ifdef CONFIG_SCST_EXTRACHECKS
BUG_ON(cmd->dev->dev_dif_type != 3);
WARN_ON(!(scst_get_dif_checks(cmd->cmd_dif_actions) & SCST_DIF_CHECK_REF_TAG));
#endif
return cmd->dev->dev_dif_static_app_ref_tag;
}
/*
* Returns format of T10-PI GUARD TAGs as one of SCST_DIF_GUARD_FORMAT_*
* constants
*/
static inline int scst_cmd_get_dif_guard_format(struct scst_cmd *cmd)
{
return cmd->tgt_dev->tgt_dev_dif_guard_format;
}
/*
* Returns block size of this cmd's device. Supposed to be used
* by target drivers during T10-PI processing.
*/
static inline int scst_cmd_get_block_size(struct scst_cmd *cmd)
{
return cmd->dev->block_size;
}
static inline unsigned int scst_get_active_cmd_count(struct scst_cmd *cmd)
{
if (likely(cmd->tgt_dev != NULL))
return atomic_read(&cmd->tgt_dev->tgt_dev_cmd_count) - 1;
else
return (unsigned int)-1;
}
int scst_set_cdb_lba(struct scst_cmd *cmd, int64_t len);
int scst_set_cdb_transf_len(struct scst_cmd *cmd, int len);
/*
* Get/Set function for mgmt cmd's target private data
*/
static inline void *scst_mgmt_cmd_get_tgt_priv(struct scst_mgmt_cmd *mcmd)
{
return mcmd->tgt_priv;
}
static inline void scst_mgmt_cmd_set_tgt_priv(struct scst_mgmt_cmd *mcmd,
void *val)
{
mcmd->tgt_priv = val;
}
/* Returns mgmt cmd's completion status (SCST_MGMT_STATUS_* constants) */
static inline int scst_mgmt_cmd_get_status(struct scst_mgmt_cmd *mcmd)
{
return mcmd->status;
}
static inline void scst_mgmt_cmd_set_status(struct scst_mgmt_cmd *mcmd,
int status)
{
/* Don't replace existing, i.e. the first, not success status */
if ((mcmd->status == SCST_MGMT_STATUS_SUCCESS) &&
(status != SCST_MGMT_STATUS_RECEIVED_STAGE_COMPLETED))
mcmd->status = status;
}
/* Returns mgmt cmd's TM fn */
static inline int scst_mgmt_cmd_get_fn(struct scst_mgmt_cmd *mcmd)
{
return mcmd->fn;
}
/* Returns true if mgmt cmd should be dropped, i.e. response not sent */
static inline bool scst_mgmt_cmd_dropped(struct scst_mgmt_cmd *mcmd)
{
return mcmd->mcmd_dropped;
}
/*
* Called by dev handler's task_mgmt_fn_*() to notify SCST core that mcmd
* is going to complete asynchronously.
*/
void scst_prepare_async_mcmd(struct scst_mgmt_cmd *mcmd);
/*
* Called by dev handler to notify SCST core that async. mcmd is completed
* with status "status".
*/
void scst_async_mcmd_completed(struct scst_mgmt_cmd *mcmd, int status);
/* Returns AEN's fn */
static inline int scst_aen_get_event_fn(struct scst_aen *aen)
{
return aen->event_fn;
}
/* Returns AEN's session */
static inline struct scst_session *scst_aen_get_sess(struct scst_aen *aen)
{
return aen->sess;
}
/* Returns AEN's LUN */
static inline __be64 scst_aen_get_lun(struct scst_aen *aen)
{
return aen->lun;
}
/* Returns SCSI AEN's sense */
static inline const uint8_t *scst_aen_get_sense(struct scst_aen *aen)
{
return aen->aen_sense;
}
/* Returns SCSI AEN's sense length */
static inline int scst_aen_get_sense_len(struct scst_aen *aen)
{
return aen->aen_sense_len;
}
/*
* Get/set functions for AEN's delivery_status. It is one of
* SCST_AEN_RES_* constants. It specifies the status of the
* command's delivery to initiator.
*/
static inline int scst_get_aen_delivery_status(struct scst_aen *aen)
{
return aen->delivery_status;
}
static inline void scst_set_aen_delivery_status(struct scst_aen *aen,
int status)
{
aen->delivery_status = status;
}
/*
* Get/Set functions for tgt's target private data
*/
static inline void *scst_get_acg_tgt_priv(struct scst_acg *acg)
{
return acg->acg_tgt_priv;
}
static inline void scst_set_acg_tgt_priv(struct scst_acg *acg, void *val)
{
acg->acg_tgt_priv = val;
}
void scst_aen_done(struct scst_aen *aen);
static inline struct scatterlist *__sg_next_inline(struct scatterlist *sg)
{
#ifdef CONFIG_SCST_EXTRACHECKS
BUG_ON(sg_is_last(sg));
#endif
sg++;
if (unlikely(sg_is_chain(sg)))
sg = sg_chain_ptr(sg);
return sg;
}
static inline struct scatterlist *sg_next_inline(struct scatterlist *sg)
{
if (sg_is_last(sg))
return NULL;
return __sg_next_inline(sg);
}
static inline void sg_clear(struct scatterlist *sg)
{
memset(sg, 0, sizeof(*sg));
#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 18, 0) && defined(CONFIG_DEBUG_SG)
sg->sg_magic = SG_MAGIC;
#endif
}
enum scst_sg_copy_dir {
SCST_SG_COPY_FROM_TARGET,
SCST_SG_COPY_TO_TARGET
};
void scst_copy_sg(struct scst_cmd *cmd, enum scst_sg_copy_dir copy_dir);
/*
* Functions for access to the commands data (SG) buffer. Should be used
* instead of direct access. Returns the buffer length for success, 0 for EOD,
* negative error code otherwise.
*
* Never EVER use this function to process only "the first page" of the buffer.
* The first SG entry can be as low as few bytes long. Use scst_get_buf_full()
* instead for such cases.
*
* "Buf" argument returns the mapped buffer
*
* The "put" function unmaps the buffer.
*/
static inline int __scst_get_buf(struct scst_cmd *cmd, int sg_cnt,
uint8_t **buf)
{
int res = 0;
struct scatterlist *sg = cmd->get_sg_buf_cur_sg_entry;
if (cmd->get_sg_buf_entry_num >= sg_cnt) {
*buf = NULL;
goto out;
}
*buf = sg_virt(sg);
res = sg->length;
cmd->get_sg_buf_entry_num++;
cmd->get_sg_buf_cur_sg_entry = sg_next_inline(sg);
out:
return res;
}
static inline int scst_get_buf_first(struct scst_cmd *cmd, uint8_t **buf)
{
if (unlikely(cmd->sg == NULL)) {
*buf = NULL;
return 0;
}
cmd->get_sg_buf_entry_num = 0;
cmd->get_sg_buf_cur_sg_entry = cmd->sg;
cmd->may_need_dma_sync = 1;
return __scst_get_buf(cmd, cmd->sg_cnt, buf);
}
static inline int scst_get_buf_next(struct scst_cmd *cmd, uint8_t **buf)
{
return __scst_get_buf(cmd, cmd->sg_cnt, buf);
}
static inline void scst_put_buf(struct scst_cmd *cmd, void *buf)
{
/* Nothing to do */
}
/*
* Functions for access to the commands DIF tags (SG) buffer. It doesn't
* return any error code, because this buffer is strictly connected to the
* data buffer, so for each block in that buffer, there must be tag here.
*
* Parameter psg on entrance specifies previous DIF tags SG in the access.
* Must point to NULL for the first access. On exit returns current DIF
* tags SG.
*
* The "put" function unmaps the buffer.
*
* !!! NOTE: this function does not check DIF SG cnt, hence must be used !!!
* !!! only inside code bound to the corresponding data SG cnt! !!!
*/
static inline uint8_t *scst_get_dif_buf(struct scst_cmd *cmd,
struct scatterlist **psg, int *length)
{
uint8_t *buf;
struct scatterlist *sg;
if (*psg == NULL)
sg = cmd->dif_sg;
else
sg = __sg_next_inline(*psg);
buf = page_address(sg_page(sg));
buf += sg->offset;
*length = sg->length;
*psg = sg;
return buf;
}
static inline void scst_put_dif_buf(struct scst_cmd *cmd, void *buf)
{
/* Nothing to do */
}
static inline int scst_get_out_buf_first(struct scst_cmd *cmd, uint8_t **buf)
{
if (unlikely(cmd->out_sg == NULL)) {
*buf = NULL;
return 0;
}
cmd->get_sg_buf_entry_num = 0;
cmd->get_sg_buf_cur_sg_entry = cmd->out_sg;
cmd->may_need_dma_sync = 1;
return __scst_get_buf(cmd, cmd->out_sg_cnt, buf);
}
static inline int scst_get_out_buf_next(struct scst_cmd *cmd, uint8_t **buf)
{
return __scst_get_buf(cmd, cmd->out_sg_cnt, buf);
}
static inline void scst_put_out_buf(struct scst_cmd *cmd, void *buf)
{
/* Nothing to do */
}
static inline int scst_get_sg_buf_first(struct scst_cmd *cmd, uint8_t **buf,
struct scatterlist *sg, int sg_cnt)
{
if (unlikely(sg == NULL)) {
*buf = NULL;
return 0;
}
cmd->get_sg_buf_entry_num = 0;
cmd->get_sg_buf_cur_sg_entry = cmd->sg;
cmd->may_need_dma_sync = 1;
return __scst_get_buf(cmd, sg_cnt, buf);
}
static inline int scst_get_sg_buf_next(struct scst_cmd *cmd, uint8_t **buf,
struct scatterlist *sg, int sg_cnt)
{
return __scst_get_buf(cmd, sg_cnt, buf);
}
static inline void scst_put_sg_buf(struct scst_cmd *cmd, void *buf,
struct scatterlist *sg, int sg_cnt)
{
/* Nothing to do */
}
/*
* Functions for access to the commands data (SG) page. Should be used
* instead of direct access. Returns the buffer length for success, 0 for EOD,
* negative error code otherwise.
*
* "Page" argument returns the starting page, "offset" - offset in it.
*
* The "put" function "puts" the buffer. It should be always be used, because
* in future may need to do some additional operations.
*/
static inline int __scst_get_sg_page(struct scst_cmd *cmd, int sg_cnt,
struct page **page, int *offset)
{
int res = 0;
struct scatterlist *sg = cmd->get_sg_buf_cur_sg_entry;
if (cmd->get_sg_buf_entry_num >= sg_cnt) {
*page = NULL;
*offset = 0;
goto out;
}
*page = sg_page(sg);
*offset = sg->offset;
res = sg->length;
cmd->get_sg_buf_entry_num++;
cmd->get_sg_buf_cur_sg_entry = sg_next_inline(sg);
out:
return res;
}
static inline int scst_get_sg_page_first(struct scst_cmd *cmd,
struct page **page, int *offset)
{
if (unlikely(cmd->sg == NULL)) {
*page = NULL;
*offset = 0;
return 0;
}
cmd->get_sg_buf_entry_num = 0;
cmd->get_sg_buf_cur_sg_entry = cmd->sg;
return __scst_get_sg_page(cmd, cmd->sg_cnt, page, offset);
}
static inline int scst_get_sg_page_next(struct scst_cmd *cmd,
struct page **page, int *offset)
{
return __scst_get_sg_page(cmd, cmd->sg_cnt, page, offset);
}
static inline void scst_put_sg_page(struct scst_cmd *cmd,
struct page *page, int offset)
{
/* Nothing to do */
}
static inline int scst_get_out_sg_page_first(struct scst_cmd *cmd,
struct page **page, int *offset)
{
if (unlikely(cmd->out_sg == NULL)) {
*page = NULL;
*offset = 0;
return 0;
}
cmd->get_sg_buf_entry_num = 0;
cmd->get_sg_buf_cur_sg_entry = cmd->out_sg;
return __scst_get_sg_page(cmd, cmd->out_sg_cnt, page, offset);
}
static inline int scst_get_out_sg_page_next(struct scst_cmd *cmd,
struct page **page, int *offset)
{
return __scst_get_sg_page(cmd, cmd->out_sg_cnt, page, offset);
}
static inline void scst_put_out_sg_page(struct scst_cmd *cmd,
struct page *page, int offset)
{
/* Nothing to do */
}
/*
* Returns approximate higher rounded buffers count that
* scst_get_buf_[first|next]() return.
*/
static inline int scst_get_buf_count(struct scst_cmd *cmd)
{
return (cmd->sg_cnt == 0) ? 1 : cmd->sg_cnt;
}
/*
* Returns approximate higher rounded buffers count that
* scst_get_out_buf_[first|next]() return.
*/
static inline int scst_get_out_buf_count(struct scst_cmd *cmd)
{
return (cmd->out_sg_cnt == 0) ? 1 : cmd->out_sg_cnt;
}
int scst_get_buf_full(struct scst_cmd *cmd, uint8_t **buf);
int scst_get_buf_full_sense(struct scst_cmd *cmd, uint8_t **buf);
void scst_put_buf_full(struct scst_cmd *cmd, uint8_t *buf);
static inline gfp_t scst_cmd_get_gfp_mask(struct scst_cmd *cmd)
{
return cmd->cmd_gfp_mask;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29) && defined(CONFIG_LOCKDEP)
extern struct lockdep_map scst_suspend_dep_map;
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 32) && \
defined(CONFIG_DEBUG_LOCK_ALLOC)
#define scst_assert_activity_suspended() \
WARN_ON(debug_locks && !lock_is_held(&scst_suspend_dep_map))
#else
/*
* See also patch "lockdep: Introduce lockdep_assert_held()" (commit ID
* f607c6685774811b8112e124f10a053d77015485)
*/
#define scst_assert_activity_suspended() do { } while (0)
#endif
/* Default suspending timeout for user interface actions */
#define SCST_SUSPEND_TIMEOUT_USER (90 * HZ)
/* No timeout in scst_suspend_activity() */
#define SCST_SUSPEND_TIMEOUT_UNLIMITED 0
int scst_suspend_activity(unsigned long timeout);
void scst_resume_activity(void);
void scst_process_active_cmd(struct scst_cmd *cmd, bool atomic);
int __scst_check_local_events(struct scst_cmd *cmd, bool preempt_tests_only);
/**
* scst_check_local_events() - check if there are any local SCSI events
*
* See description of __scst_check_local_events().
*
* Dev handlers implementing internal queuing in their exec() callback should
* call this function just before the actual command's execution (i.e.
* after it's taken from the internal queue).
*/
static inline int scst_check_local_events(struct scst_cmd *cmd)
{
return __scst_check_local_events(cmd, true);
}
int scst_get_cmd_abnormal_done_state(struct scst_cmd *cmd);
void scst_set_cmd_abnormal_done_state(struct scst_cmd *cmd);
struct scst_trace_log {
unsigned int val;
const char *token;
};
extern struct mutex scst_mutex;
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 34))
const struct sysfs_ops *scst_sysfs_get_sysfs_ops(void);
#else
struct sysfs_ops *scst_sysfs_get_sysfs_ops(void);
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29) && defined(CONFIG_LOCKDEP)
#define SCST_SET_DEP_MAP(work, dm) ((work)->dep_map = (dm))
#define SCST_KOBJECT_PUT_AND_WAIT(kobj, category, c, dep_map) \
scst_kobject_put_and_wait(kobj, category, c, dep_map)
void scst_kobject_put_and_wait(struct kobject *kobj, const char *category,
struct completion *c,
struct lockdep_map *dep_map);
#else
#define SCST_SET_DEP_MAP(work, dm) do { } while (0)
#define SCST_KOBJECT_PUT_AND_WAIT(kobj, category, c, dep_map) \
scst_kobject_put_and_wait(kobj, category, c)
void scst_kobject_put_and_wait(struct kobject *kobj, const char *category,
struct completion *c);
#endif
/*
* Returns target driver's root sysfs kobject.
* The driver can create own files/directories/links here.
*/
static inline struct kobject *scst_sysfs_get_tgtt_kobj(
struct scst_tgt_template *tgtt)
{
return &tgtt->tgtt_kobj;
}
int scst_create_tgtt_attr(struct scst_tgt_template *tgtt,
struct kobj_attribute *attribute);
/*
* Returns target's root sysfs kobject.
* The driver can create own files/directories/links here.
*/
static inline struct kobject *scst_sysfs_get_tgt_kobj(
struct scst_tgt *tgt)
{
return &tgt->tgt_kobj;
}
int scst_create_tgt_attr(struct scst_tgt *tgt,
struct kobj_attribute *attribute);
/*
* Returns device handler's root sysfs kobject.
* The driver can create own files/directories/links here.
*/
static inline struct kobject *scst_sysfs_get_devt_kobj(
struct scst_dev_type *devt)
{
return &devt->devt_kobj;
}
int scst_create_devt_attr(struct scst_dev_type *devt,
struct kobj_attribute *attribute);
/*
* Returns device's root sysfs kobject.
* The driver can create own files/directories/links here.
*/
static inline struct kobject *scst_sysfs_get_dev_kobj(
struct scst_device *dev)
{
return &dev->dev_kobj;
}
int scst_create_dev_attr(struct scst_device *dev,
struct kobj_attribute *attribute);
/*
* Returns session's root sysfs kobject.
* The driver can create own files/directories/links here.
*/
static inline struct kobject *scst_sysfs_get_sess_kobj(
struct scst_session *sess)
{
return &sess->sess_kobj;
}
/* Returns target name */
static inline const char *scst_get_tgt_name(const struct scst_tgt *tgt)
{
return tgt->tgt_name;
}
int scst_alloc_sense(struct scst_cmd *cmd, int atomic);
int scst_alloc_set_sense(struct scst_cmd *cmd, int atomic,
const uint8_t *sense, unsigned int len);
int scst_set_sense(uint8_t *buffer, int len, bool d_sense,
int key, int asc, int ascq);
#define SCST_INVAL_FIELD_BIT_OFFS_VALID 0x8000
int scst_set_invalid_field_in_cdb(struct scst_cmd *cmd, int field_offs,
int bit_offs);
int scst_set_invalid_field_in_parm_list(struct scst_cmd *cmd, int field_offs,
int bit_offs);
bool scst_is_ua_sense(const uint8_t *sense, int len);
bool scst_analyze_sense(const uint8_t *sense, int len,
unsigned int valid_mask, int key, int asc, int ascq);
unsigned long scst_random(void);
void scst_set_resp_data_len(struct scst_cmd *cmd, int resp_data_len);
void scst_cmd_get(struct scst_cmd *cmd);
void scst_cmd_put(struct scst_cmd *cmd);
struct scatterlist *scst_alloc_sg(int size, gfp_t gfp_mask, int *count);
void scst_free_sg(struct scatterlist *sg, int count);
int scst_calc_block_shift(int sector_size);
int scst_sbc_generic_parse(struct scst_cmd *cmd);
int scst_cdrom_generic_parse(struct scst_cmd *cmd);
int scst_modisk_generic_parse(struct scst_cmd *cmd);
int scst_tape_generic_parse(struct scst_cmd *cmd);
int scst_changer_generic_parse(struct scst_cmd *cmd);
int scst_processor_generic_parse(struct scst_cmd *cmd);
int scst_raid_generic_parse(struct scst_cmd *cmd);
int scst_block_generic_dev_done(struct scst_cmd *cmd,
void (*set_block_shift)(struct scst_cmd *cmd, int block_shift));
int scst_tape_generic_dev_done(struct scst_cmd *cmd,
void (*set_block_size)(struct scst_cmd *cmd, int block_size));
int scst_obtain_device_parameters(struct scst_device *dev,
const uint8_t *mode_select_cdb);
void scst_reassign_retained_sess_states(struct scst_session *new_sess,
struct scst_session *old_sess);
int scst_get_max_lun_commands(struct scst_session *sess, uint64_t lun);
void scst_dev_inquiry_data_changed(struct scst_device *dev);
/*
* Has to be put here open coded, because Linux doesn't have equivalent, which
* allows exclusive wake ups of threads in LIFO order. We need it to let (yet)
* unneeded threads sleep and not pollute CPU cache by their stacks.
*/
#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 13, 0)
static inline void prepare_to_wait_exclusive_head(wait_queue_head_t *q,
wait_queue_t *wait, int state)
{
unsigned long flags;
wait->flags |= WQ_FLAG_EXCLUSIVE;
spin_lock_irqsave(&q->lock, flags);
if (list_empty(&wait->task_list))
__add_wait_queue(q, wait);
set_current_state(state);
spin_unlock_irqrestore(&q->lock, flags);
}
#else
static inline void prepare_to_wait_exclusive_head(struct wait_queue_head *wq_head,
struct wait_queue_entry *wq_entry, int state)
{
unsigned long flags;
wq_entry->flags |= WQ_FLAG_EXCLUSIVE;
spin_lock_irqsave(&wq_head->lock, flags);
if (list_empty(&wq_entry->entry))
__add_wait_queue(wq_head, wq_entry);
set_current_state(state);
spin_unlock_irqrestore(&wq_head->lock, flags);
}
#endif
/**
* wait_event_locked() - Wait until a condition becomes true.
* @wq: Wait queue to wait on if @condition is false.
* @condition: Condition to wait for. Can be any C expression.
* @lock_type: One of lock, lock_bh or lock_irq.
* @lock: A spinlock.
*
* Caller must hold lock of type @lock_type on @lock.
*/
#define wait_event_locked(wq, condition, lock_type, lock) do { \
if (!(condition)) { \
DEFINE_WAIT(__wait); \
\
do { \
prepare_to_wait_exclusive_head(&(wq), &__wait, \
TASK_INTERRUPTIBLE); \
if (condition) \
break; \
spin_un ## lock_type(&(lock)); \
schedule(); \
spin_ ## lock_type(&(lock)); \
} while (!(condition)); \
finish_wait(&(wq), &__wait); \
} \
} while (0)
/* Only use get_unaligned_be24() if reading p - 1 is allowed. */
static inline uint32_t get_unaligned_be24(const uint8_t *const p)
{
return get_unaligned_be32(p - 1) & 0xffffffU;
}
static inline void put_unaligned_be24(const uint32_t v, uint8_t *const p)
{
p[0] = v >> 16;
p[1] = v >> 8;
p[2] = v >> 0;
}
#if defined(CONFIG_SCST_DEBUG) || defined(CONFIG_SCST_TRACING)
const char *scst_get_opcode_name(struct scst_cmd *cmd);
#else
static inline const char *scst_get_opcode_name(struct scst_cmd *cmd)
{
return cmd->op_name;
}
#endif
/*
* Structure to match events to user space and replies on them
*/
struct scst_sysfs_user_info {
/* Unique cookie to identify request */
uint32_t info_cookie;
/* Entry in the global list */
struct list_head info_list_entry;
/* Set if reply from the user space is being executed */
unsigned int info_being_executed:1;
/* Set if this info is in the info_list */
unsigned int info_in_list:1;
/* Completion to wait on for the request completion */
struct completion info_completion;
/* Request completion status and optional data */
int info_status;
void *data;
};
int scst_sysfs_user_add_info(struct scst_sysfs_user_info **out_info);
void scst_sysfs_user_del_info(struct scst_sysfs_user_info *info);
struct scst_sysfs_user_info *scst_sysfs_user_get_info(uint32_t cookie);
int scst_wait_info_completion(struct scst_sysfs_user_info *info,
unsigned long timeout);
unsigned int scst_get_setup_id(void);
/*
* Needed to avoid potential circular locking dependency between scst_mutex
* and internal sysfs locking (s_active). It could be since most sysfs entries
* are created and deleted under scst_mutex AND scst_mutex is taken inside
* sysfs functions. So, we push from the sysfs functions all the processing
* taking scst_mutex. To avoid deadlock, we return from them with EAGAIN
* if processing is taking too long. User space then should poll
* last_sysfs_mgmt_res until it returns the result of the processing
* (something other than EAGAIN).
*/
struct scst_sysfs_work_item {
/*
* If true, then last_sysfs_mgmt_res will not be updated. This is
* needed to allow read only sysfs monitoring during management actions.
* All management actions are supposed to be externally serialized,
* so then last_sysfs_mgmt_res automatically serialized too.
* Otherwise a monitoring action can overwrite value of simultaneous
* management action's last_sysfs_mgmt_res.
*/
bool read_only_action;
struct list_head sysfs_work_list_entry;
struct kref sysfs_work_kref;
int (*sysfs_work_fn)(struct scst_sysfs_work_item *work);
struct completion sysfs_work_done;
char *buf;
/*
* If the caller of scst_sysfs_queue_wait_work() holds a reference on
* a kobject, must point at the lockdep_map structure associated with
* that kobject.
*/
struct lockdep_map *dep_map;
union {
struct scst_dev_type *devt;
struct scst_tgt_template *tgtt;
struct {
struct scst_tgt *tgt;
struct scst_acg *acg;
union {
bool is_tgt_kobj;
int io_grouping_type;
bool enable;
cpumask_t cpu_mask;
};
};
struct {
struct scst_device *dev;
union {
int new_threads_num;
bool default_val;
};
enum scst_dev_type_threads_pool_type new_threads_pool_type;
};
struct scst_session *sess;
struct {
struct scst_tgt *tgt_r;
unsigned long rel_tgt_id;
};
struct {
struct kobject *kobj;
};
};
int work_res;
char *res_buf;
};
int scst_alloc_sysfs_work(int (*sysfs_work_fn)(struct scst_sysfs_work_item *),
bool read_only_action, struct scst_sysfs_work_item **res_work);
int scst_sysfs_queue_wait_work(struct scst_sysfs_work_item *work);
void scst_sysfs_work_get(struct scst_sysfs_work_item *work);
void scst_sysfs_work_put(struct scst_sysfs_work_item *work);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)
#ifdef CONFIG_LOCKDEP
extern struct lockdep_map scst_dev_dep_map;
#endif
#endif
char *scst_get_next_lexem(char **token_str);
void scst_restore_token_str(char *prev_lexem, char *token_str);
char *scst_get_next_token_str(char **input_str);
void scst_init_threads(struct scst_cmd_threads *cmd_threads);
void scst_deinit_threads(struct scst_cmd_threads *cmd_threads);
void scst_pass_through_cmd_done(void *data, char *sense, int result, int resid);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 30)
int scst_scsi_exec_async(struct scst_cmd *cmd, void *data,
void (*done)(void *data, char *sense, int result, int resid));
#endif
int scst_get_file_mode(const char *path);
bool scst_parent_dir_exists(const char *path);
struct scst_data_descriptor {
uint64_t sdd_lba;
uint64_t sdd_blocks;
};
ssize_t scst_readv(struct file *file, const struct iovec *vec,
unsigned long vlen, loff_t *pos);
ssize_t scst_writev(struct file *file, const struct iovec *vec,
unsigned long vlen, loff_t *pos);
void scst_write_same(struct scst_cmd *cmd, struct scst_data_descriptor *where);
/**
* scsi_execute - insert a SCSI request and wait for the result
* @sdev: scsi device
* @cmd: scsi command
* @data_direction: data direction
* @buffer: data buffer
* @bufflen: length of buffer - DMA_TO_DEVICE, DMA_FROM_DEVICE or DMA_NONE
* @sense: optional sense buffer
* @timeout: request timeout in seconds
* @retries: number of times to retry request
* @flags: flags for ->cmd_flags, e.g. REQ_FAILFAST_DEV
*
* Returns the scsi_cmnd result field if a command was executed, or a negative
* Linux error code if we didn't get that far.
*/
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0)
#define scst_scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense, \
timeout, retries, flags) \
scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense, \
NULL /* sshdr */, timeout, retries, flags, \
0 /* rq_flags */, NULL /* resid */)
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)
#define scst_scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense, \
timeout, retries, flags) \
scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense, \
timeout, retries, flags, NULL /* resid */)
#else
#define scst_scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense, \
timeout, retries, flags) \
scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense, \
timeout, retries, flags)
#endif
__be64 scst_pack_lun(const uint64_t lun, enum scst_lun_addr_method addr_method);
uint64_t scst_unpack_lun(const uint8_t *lun, int len);
int scst_save_global_mode_pages(const struct scst_device *dev,
uint8_t *buf, int size);
int scst_restore_global_mode_pages(struct scst_device *dev, char *params,
char **last_param);
int scst_read_file_transactional(const char *name, const char *name1,
const char *signature, int signature_len, uint8_t *buf, int size);
int scst_write_file_transactional(const char *name, const char *name1,
const char *signature, int signature_len, const uint8_t *buf, int size);
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 39)
void scst_path_put(struct nameidata *nd);
#endif
int scst_remove_file(const char *name);
void scst_set_tp_soft_threshold_reached_UA(struct scst_tgt_dev *tgt_dev);
int scst_pr_set_cluster_mode(struct scst_device *dev, bool cluster_mode,
const char *cl_dev_id);
int scst_pr_init_dev(struct scst_device *dev);
void scst_pr_clear_dev(struct scst_device *dev);
/* Global ALUA lock/unlock functions */
void scst_alua_lock(void);
void scst_alua_unlock(void);
void lockdep_assert_alua_lock_held(void);
struct scst_ext_copy_data_descr {
uint64_t src_lba;
uint64_t dst_lba;
int data_len; /* in bytes */
};
struct scst_ext_copy_seg_descr {
#define SCST_EXT_COPY_SEG_DATA 0
#if 0 /* not implemented yet */
#define SCST_EXT_COPY_SEG_PR_REG 1
#define SCST_EXT_COPY_SEG_PR_MOVE 2
#endif
int type;
union {
struct {
struct scst_tgt_dev *src_tgt_dev;
struct scst_tgt_dev *dst_tgt_dev;
struct scst_ext_copy_data_descr data_descr;
};
};
/* Internal, don't touch! */
int tgt_descr_offs;
};
void scst_ext_copy_remap_done(struct scst_cmd *ec_cmd,
struct scst_ext_copy_data_descr *dds, int dds_cnt);
int scst_ext_copy_get_cur_seg_data_len(struct scst_cmd *ec_cmd);
#endif /* __SCST_H */
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