Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 619 insertions, 0 deletions

diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
new file mode 100644
index 000000000..3642b8e39
--- /dev/null
+++ b/include/scsi/scsi_device.h
@@ -0,0 +1,619 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _SCSI_SCSI_DEVICE_H
+#define _SCSI_SCSI_DEVICE_H
+
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/blk-mq.h>
+#include <scsi/scsi.h>
+#include <linux/atomic.h>
+#include <linux/sbitmap.h>
+
+struct bsg_device;
+struct device;
+struct request_queue;
+struct scsi_cmnd;
+struct scsi_lun;
+struct scsi_sense_hdr;
+
+typedef __u64 __bitwise blist_flags_t;
+
+#define SCSI_SENSE_BUFFERSIZE	96
+
+struct scsi_mode_data {
+	__u32	length;
+	__u16	block_descriptor_length;
+	__u8	medium_type;
+	__u8	device_specific;
+	__u8	header_length;
+	__u8	longlba:1;
+};
+
+/*
+ * sdev state: If you alter this, you also need to alter scsi_sysfs.c
+ * (for the ascii descriptions) and the state model enforcer:
+ * scsi_lib:scsi_device_set_state().
+ */
+enum scsi_device_state {
+	SDEV_CREATED = 1,	/* device created but not added to sysfs
+				 * Only internal commands allowed (for inq) */
+	SDEV_RUNNING,		/* device properly configured
+				 * All commands allowed */
+	SDEV_CANCEL,		/* beginning to delete device
+				 * Only error handler commands allowed */
+	SDEV_DEL,		/* device deleted 
+				 * no commands allowed */
+	SDEV_QUIESCE,		/* Device quiescent.  No block commands
+				 * will be accepted, only specials (which
+				 * originate in the mid-layer) */
+	SDEV_OFFLINE,		/* Device offlined (by error handling or
+				 * user request */
+	SDEV_TRANSPORT_OFFLINE,	/* Offlined by transport class error handler */
+	SDEV_BLOCK,		/* Device blocked by scsi lld.  No
+				 * scsi commands from user or midlayer
+				 * should be issued to the scsi
+				 * lld. */
+	SDEV_CREATED_BLOCK,	/* same as above but for created devices */
+};
+
+enum scsi_scan_mode {
+	SCSI_SCAN_INITIAL = 0,
+	SCSI_SCAN_RESCAN,
+	SCSI_SCAN_MANUAL,
+};
+
+enum scsi_device_event {
+	SDEV_EVT_MEDIA_CHANGE	= 1,	/* media has changed */
+	SDEV_EVT_INQUIRY_CHANGE_REPORTED,		/* 3F 03  UA reported */
+	SDEV_EVT_CAPACITY_CHANGE_REPORTED,		/* 2A 09  UA reported */
+	SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED,	/* 38 07  UA reported */
+	SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED,	/* 2A 01  UA reported */
+	SDEV_EVT_LUN_CHANGE_REPORTED,			/* 3F 0E  UA reported */
+	SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,		/* 2A 06  UA reported */
+	SDEV_EVT_POWER_ON_RESET_OCCURRED,		/* 29 00  UA reported */
+
+	SDEV_EVT_FIRST		= SDEV_EVT_MEDIA_CHANGE,
+	SDEV_EVT_LAST		= SDEV_EVT_POWER_ON_RESET_OCCURRED,
+
+	SDEV_EVT_MAXBITS	= SDEV_EVT_LAST + 1
+};
+
+struct scsi_event {
+	enum scsi_device_event	evt_type;
+	struct list_head	node;
+
+	/* put union of data structures, for non-simple event types,
+	 * here
+	 */
+};
+
+/**
+ * struct scsi_vpd - SCSI Vital Product Data
+ * @rcu: For kfree_rcu().
+ * @len: Length in bytes of @data.
+ * @data: VPD data as defined in various T10 SCSI standard documents.
+ */
+struct scsi_vpd {
+	struct rcu_head	rcu;
+	int		len;
+	unsigned char	data[];
+};
+
+enum scsi_vpd_parameters {
+	SCSI_VPD_HEADER_SIZE = 4,
+};
+
+struct scsi_device {
+	struct Scsi_Host *host;
+	struct request_queue *request_queue;
+
+	/* the next two are protected by the host->host_lock */
+	struct list_head    siblings;   /* list of all devices on this host */
+	struct list_head    same_target_siblings; /* just the devices sharing same target id */
+
+	struct sbitmap budget_map;
+	atomic_t device_blocked;	/* Device returned QUEUE_FULL. */
+
+	atomic_t restarts;
+	spinlock_t list_lock;
+	struct list_head starved_entry;
+	unsigned short queue_depth;	/* How deep of a queue we want */
+	unsigned short max_queue_depth;	/* max queue depth */
+	unsigned short last_queue_full_depth; /* These two are used by */
+	unsigned short last_queue_full_count; /* scsi_track_queue_full() */
+	unsigned long last_queue_full_time;	/* last queue full time */
+	unsigned long queue_ramp_up_period;	/* ramp up period in jiffies */
+#define SCSI_DEFAULT_RAMP_UP_PERIOD	(120 * HZ)
+
+	unsigned long last_queue_ramp_up;	/* last queue ramp up time */
+
+	unsigned int id, channel;
+	u64 lun;
+	unsigned int manufacturer;	/* Manufacturer of device, for using 
+					 * vendor-specific cmd's */
+	unsigned sector_size;	/* size in bytes */
+
+	void *hostdata;		/* available to low-level driver */
+	unsigned char type;
+	char scsi_level;
+	char inq_periph_qual;	/* PQ from INQUIRY data */	
+	struct mutex inquiry_mutex;
+	unsigned char inquiry_len;	/* valid bytes in 'inquiry' */
+	unsigned char * inquiry;	/* INQUIRY response data */
+	const char * vendor;		/* [back_compat] point into 'inquiry' ... */
+	const char * model;		/* ... after scan; point to static string */
+	const char * rev;		/* ... "nullnullnullnull" before scan */
+
+	struct scsi_vpd __rcu *vpd_pg0;
+	struct scsi_vpd __rcu *vpd_pg83;
+	struct scsi_vpd __rcu *vpd_pg80;
+	struct scsi_vpd __rcu *vpd_pg89;
+	struct scsi_vpd __rcu *vpd_pgb0;
+	struct scsi_vpd __rcu *vpd_pgb1;
+	struct scsi_vpd __rcu *vpd_pgb2;
+
+	struct scsi_target      *sdev_target;
+
+	blist_flags_t		sdev_bflags; /* black/white flags as also found in
+				 * scsi_devinfo.[hc]. For now used only to
+				 * pass settings from slave_alloc to scsi
+				 * core. */
+	unsigned int eh_timeout; /* Error handling timeout */
+	unsigned removable:1;
+	unsigned changed:1;	/* Data invalid due to media change */
+	unsigned busy:1;	/* Used to prevent races */
+	unsigned lockable:1;	/* Able to prevent media removal */
+	unsigned locked:1;      /* Media removal disabled */
+	unsigned borken:1;	/* Tell the Seagate driver to be 
+				 * painfully slow on this device */
+	unsigned disconnect:1;	/* can disconnect */
+	unsigned soft_reset:1;	/* Uses soft reset option */
+	unsigned sdtr:1;	/* Device supports SDTR messages */
+	unsigned wdtr:1;	/* Device supports WDTR messages */
+	unsigned ppr:1;		/* Device supports PPR messages */
+	unsigned tagged_supported:1;	/* Supports SCSI-II tagged queuing */
+	unsigned simple_tags:1;	/* simple queue tag messages are enabled */
+	unsigned was_reset:1;	/* There was a bus reset on the bus for 
+				 * this device */
+	unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
+				     * because we did a bus reset. */
+	unsigned use_10_for_rw:1; /* first try 10-byte read / write */
+	unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
+	unsigned set_dbd_for_ms:1; /* Set "DBD" field in mode sense */
+	unsigned no_report_opcodes:1;	/* no REPORT SUPPORTED OPERATION CODES */
+	unsigned no_write_same:1;	/* no WRITE SAME command */
+	unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
+	unsigned use_16_for_sync:1;	/* Use sync (16) over sync (10) */
+	unsigned skip_ms_page_8:1;	/* do not use MODE SENSE page 0x08 */
+	unsigned skip_ms_page_3f:1;	/* do not use MODE SENSE page 0x3f */
+	unsigned skip_vpd_pages:1;	/* do not read VPD pages */
+	unsigned try_vpd_pages:1;	/* attempt to read VPD pages */
+	unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
+	unsigned no_start_on_add:1;	/* do not issue start on add */
+	unsigned allow_restart:1; /* issue START_UNIT in error handler */
+	unsigned manage_start_stop:1;	/* Let HLD (sd) manage start/stop */
+	unsigned start_stop_pwr_cond:1;	/* Set power cond. in START_STOP_UNIT */
+	unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
+	unsigned select_no_atn:1;
+	unsigned fix_capacity:1;	/* READ_CAPACITY is too high by 1 */
+	unsigned guess_capacity:1;	/* READ_CAPACITY might be too high by 1 */
+	unsigned retry_hwerror:1;	/* Retry HARDWARE_ERROR */
+	unsigned last_sector_bug:1;	/* do not use multisector accesses on
+					   SD_LAST_BUGGY_SECTORS */
+	unsigned no_read_disc_info:1;	/* Avoid READ_DISC_INFO cmds */
+	unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */
+	unsigned try_rc_10_first:1;	/* Try READ_CAPACACITY_10 first */
+	unsigned security_supported:1;	/* Supports Security Protocols */
+	unsigned is_visible:1;	/* is the device visible in sysfs */
+	unsigned wce_default_on:1;	/* Cache is ON by default */
+	unsigned no_dif:1;	/* T10 PI (DIF) should be disabled */
+	unsigned broken_fua:1;		/* Don't set FUA bit */
+	unsigned lun_in_cdb:1;		/* Store LUN bits in CDB[1] */
+	unsigned unmap_limit_for_ws:1;	/* Use the UNMAP limit for WRITE SAME */
+	unsigned rpm_autosuspend:1;	/* Enable runtime autosuspend at device
+					 * creation time */
+	unsigned ignore_media_change:1; /* Ignore MEDIA CHANGE on resume */
+	unsigned silence_suspend:1;	/* Do not print runtime PM related messages */
+
+	unsigned int queue_stopped;	/* request queue is quiesced */
+	bool offline_already;		/* Device offline message logged */
+
+	atomic_t disk_events_disable_depth; /* disable depth for disk events */
+
+	DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
+	DECLARE_BITMAP(pending_events, SDEV_EVT_MAXBITS); /* pending events */
+	struct list_head event_list;	/* asserted events */
+	struct work_struct event_work;
+
+	unsigned int max_device_blocked; /* what device_blocked counts down from  */
+#define SCSI_DEFAULT_DEVICE_BLOCKED	3
+
+	atomic_t iorequest_cnt;
+	atomic_t iodone_cnt;
+	atomic_t ioerr_cnt;
+	atomic_t iotmo_cnt;
+
+	struct device		sdev_gendev,
+				sdev_dev;
+
+	struct work_struct	requeue_work;
+
+	struct scsi_device_handler *handler;
+	void			*handler_data;
+
+	size_t			dma_drain_len;
+	void			*dma_drain_buf;
+
+	unsigned int		sg_timeout;
+	unsigned int		sg_reserved_size;
+
+	struct bsg_device	*bsg_dev;
+	unsigned char		access_state;
+	struct mutex		state_mutex;
+	enum scsi_device_state sdev_state;
+	struct task_struct	*quiesced_by;
+	unsigned long		sdev_data[];
+} __attribute__((aligned(sizeof(unsigned long))));
+
+#define	to_scsi_device(d)	\
+	container_of(d, struct scsi_device, sdev_gendev)
+#define	class_to_sdev(d)	\
+	container_of(d, struct scsi_device, sdev_dev)
+#define transport_class_to_sdev(class_dev) \
+	to_scsi_device(class_dev->parent)
+
+#define sdev_dbg(sdev, fmt, a...) \
+	dev_dbg(&(sdev)->sdev_gendev, fmt, ##a)
+
+/*
+ * like scmd_printk, but the device name is passed in
+ * as a string pointer
+ */
+__printf(4, 5) void
+sdev_prefix_printk(const char *, const struct scsi_device *, const char *,
+		const char *, ...);
+
+#define sdev_printk(l, sdev, fmt, a...)				\
+	sdev_prefix_printk(l, sdev, NULL, fmt, ##a)
+
+__printf(3, 4) void
+scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
+
+#define scmd_dbg(scmd, fmt, a...)					\
+	do {								\
+		struct request *__rq = scsi_cmd_to_rq((scmd));		\
+									\
+		if (__rq->q->disk)					\
+			sdev_dbg((scmd)->device, "[%s] " fmt,		\
+				 __rq->q->disk->disk_name, ##a);	\
+		else							\
+			sdev_dbg((scmd)->device, fmt, ##a);		\
+	} while (0)
+
+enum scsi_target_state {
+	STARGET_CREATED = 1,
+	STARGET_RUNNING,
+	STARGET_REMOVE,
+	STARGET_CREATED_REMOVE,
+	STARGET_DEL,
+};
+
+/*
+ * scsi_target: representation of a scsi target, for now, this is only
+ * used for single_lun devices. If no one has active IO to the target,
+ * starget_sdev_user is NULL, else it points to the active sdev.
+ */
+struct scsi_target {
+	struct scsi_device	*starget_sdev_user;
+	struct list_head	siblings;
+	struct list_head	devices;
+	struct device		dev;
+	struct kref		reap_ref; /* last put renders target invisible */
+	unsigned int		channel;
+	unsigned int		id; /* target id ... replace
+				     * scsi_device.id eventually */
+	unsigned int		create:1; /* signal that it needs to be added */
+	unsigned int		single_lun:1;	/* Indicates we should only
+						 * allow I/O to one of the luns
+						 * for the device at a time. */
+	unsigned int		pdt_1f_for_no_lun:1;	/* PDT = 0x1f
+						 * means no lun present. */
+	unsigned int		no_report_luns:1;	/* Don't use
+						 * REPORT LUNS for scanning. */
+	unsigned int		expecting_lun_change:1;	/* A device has reported
+						 * a 3F/0E UA, other devices on
+						 * the same target will also. */
+	/* commands actually active on LLD. */
+	atomic_t		target_busy;
+	atomic_t		target_blocked;
+
+	/*
+	 * LLDs should set this in the slave_alloc host template callout.
+	 * If set to zero then there is not limit.
+	 */
+	unsigned int		can_queue;
+	unsigned int		max_target_blocked;
+#define SCSI_DEFAULT_TARGET_BLOCKED	3
+
+	char			scsi_level;
+	enum scsi_target_state	state;
+	void 			*hostdata; /* available to low-level driver */
+	unsigned long		starget_data[]; /* for the transport */
+	/* starget_data must be the last element!!!! */
+} __attribute__((aligned(sizeof(unsigned long))));
+
+#define to_scsi_target(d)	container_of(d, struct scsi_target, dev)
+static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
+{
+	return to_scsi_target(sdev->sdev_gendev.parent);
+}
+#define transport_class_to_starget(class_dev) \
+	to_scsi_target(class_dev->parent)
+
+#define starget_printk(prefix, starget, fmt, a...)	\
+	dev_printk(prefix, &(starget)->dev, fmt, ##a)
+
+extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
+		uint, uint, u64, void *hostdata);
+extern int scsi_add_device(struct Scsi_Host *host, uint channel,
+			   uint target, u64 lun);
+extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
+extern void scsi_remove_device(struct scsi_device *);
+extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
+void scsi_attach_vpd(struct scsi_device *sdev);
+
+extern struct scsi_device *scsi_device_from_queue(struct request_queue *q);
+extern int __must_check scsi_device_get(struct scsi_device *);
+extern void scsi_device_put(struct scsi_device *);
+extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
+					      uint, uint, u64);
+extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
+						uint, uint, u64);
+extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
+							u64);
+extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
+							  u64);
+extern void starget_for_each_device(struct scsi_target *, void *,
+		     void (*fn)(struct scsi_device *, void *));
+extern void __starget_for_each_device(struct scsi_target *, void *,
+				      void (*fn)(struct scsi_device *,
+						 void *));
+
+/* only exposed to implement shost_for_each_device */
+extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
+						  struct scsi_device *);
+
+/**
+ * shost_for_each_device - iterate over all devices of a host
+ * @sdev: the &struct scsi_device to use as a cursor
+ * @shost: the &struct scsi_host to iterate over
+ *
+ * Iterator that returns each device attached to @shost.  This loop
+ * takes a reference on each device and releases it at the end.  If
+ * you break out of the loop, you must call scsi_device_put(sdev).
+ */
+#define shost_for_each_device(sdev, shost) \
+	for ((sdev) = __scsi_iterate_devices((shost), NULL); \
+	     (sdev); \
+	     (sdev) = __scsi_iterate_devices((shost), (sdev)))
+
+/**
+ * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
+ * @sdev: the &struct scsi_device to use as a cursor
+ * @shost: the &struct scsi_host to iterate over
+ *
+ * Iterator that returns each device attached to @shost.  It does _not_
+ * take a reference on the scsi_device, so the whole loop must be
+ * protected by shost->host_lock.
+ *
+ * Note: The only reason to use this is because you need to access the
+ * device list in interrupt context.  Otherwise you really want to use
+ * shost_for_each_device instead.
+ */
+#define __shost_for_each_device(sdev, shost) \
+	list_for_each_entry((sdev), &((shost)->__devices), siblings)
+
+extern int scsi_change_queue_depth(struct scsi_device *, int);
+extern int scsi_track_queue_full(struct scsi_device *, int);
+
+extern int scsi_set_medium_removal(struct scsi_device *, char);
+
+extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
+			   unsigned char *buffer, int len, int timeout,
+			   int retries, struct scsi_mode_data *data,
+			   struct scsi_sense_hdr *);
+extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
+			    unsigned char *buffer, int len, int timeout,
+			    int retries, struct scsi_mode_data *data,
+			    struct scsi_sense_hdr *);
+extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
+				int retries, struct scsi_sense_hdr *sshdr);
+extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
+			     int buf_len);
+extern int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
+			      unsigned int len, unsigned char opcode);
+extern int scsi_device_set_state(struct scsi_device *sdev,
+				 enum scsi_device_state state);
+extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
+					  gfp_t gfpflags);
+extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
+extern void sdev_evt_send_simple(struct scsi_device *sdev,
+			  enum scsi_device_event evt_type, gfp_t gfpflags);
+extern int scsi_device_quiesce(struct scsi_device *sdev);
+extern void scsi_device_resume(struct scsi_device *sdev);
+extern void scsi_target_quiesce(struct scsi_target *);
+extern void scsi_target_resume(struct scsi_target *);
+extern void scsi_scan_target(struct device *parent, unsigned int channel,
+			     unsigned int id, u64 lun,
+			     enum scsi_scan_mode rescan);
+extern void scsi_target_reap(struct scsi_target *);
+extern void scsi_target_block(struct device *);
+extern void scsi_target_unblock(struct device *, enum scsi_device_state);
+extern void scsi_remove_target(struct device *);
+extern const char *scsi_device_state_name(enum scsi_device_state);
+extern int scsi_is_sdev_device(const struct device *);
+extern int scsi_is_target_device(const struct device *);
+extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
+extern int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
+			int data_direction, void *buffer, unsigned bufflen,
+			unsigned char *sense, struct scsi_sense_hdr *sshdr,
+			int timeout, int retries, blk_opf_t flags,
+			req_flags_t rq_flags, int *resid);
+/* Make sure any sense buffer is the correct size. */
+#define scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense,	\
+		     sshdr, timeout, retries, flags, rq_flags, resid)	\
+({									\
+	BUILD_BUG_ON((sense) != NULL &&					\
+		     sizeof(sense) != SCSI_SENSE_BUFFERSIZE);		\
+	__scsi_execute(sdev, cmd, data_direction, buffer, bufflen,	\
+		       sense, sshdr, timeout, retries, flags, rq_flags,	\
+		       resid);						\
+})
+static inline int scsi_execute_req(struct scsi_device *sdev,
+	const unsigned char *cmd, int data_direction, void *buffer,
+	unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
+	int retries, int *resid)
+{
+	return scsi_execute(sdev, cmd, data_direction, buffer,
+		bufflen, NULL, sshdr, timeout, retries,  0, 0, resid);
+}
+extern void sdev_disable_disk_events(struct scsi_device *sdev);
+extern void sdev_enable_disk_events(struct scsi_device *sdev);
+extern int scsi_vpd_lun_id(struct scsi_device *, char *, size_t);
+extern int scsi_vpd_tpg_id(struct scsi_device *, int *);
+
+#ifdef CONFIG_PM
+extern int scsi_autopm_get_device(struct scsi_device *);
+extern void scsi_autopm_put_device(struct scsi_device *);
+#else
+static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
+static inline void scsi_autopm_put_device(struct scsi_device *d) {}
+#endif /* CONFIG_PM */
+
+static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
+{
+	return device_reprobe(&sdev->sdev_gendev);
+}
+
+static inline unsigned int sdev_channel(struct scsi_device *sdev)
+{
+	return sdev->channel;
+}
+
+static inline unsigned int sdev_id(struct scsi_device *sdev)
+{
+	return sdev->id;
+}
+
+#define scmd_id(scmd) sdev_id((scmd)->device)
+#define scmd_channel(scmd) sdev_channel((scmd)->device)
+
+/*
+ * checks for positions of the SCSI state machine
+ */
+static inline int scsi_device_online(struct scsi_device *sdev)
+{
+	return (sdev->sdev_state != SDEV_OFFLINE &&
+		sdev->sdev_state != SDEV_TRANSPORT_OFFLINE &&
+		sdev->sdev_state != SDEV_DEL);
+}
+static inline int scsi_device_blocked(struct scsi_device *sdev)
+{
+	return sdev->sdev_state == SDEV_BLOCK ||
+		sdev->sdev_state == SDEV_CREATED_BLOCK;
+}
+static inline int scsi_device_created(struct scsi_device *sdev)
+{
+	return sdev->sdev_state == SDEV_CREATED ||
+		sdev->sdev_state == SDEV_CREATED_BLOCK;
+}
+
+int scsi_internal_device_block_nowait(struct scsi_device *sdev);
+int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
+					enum scsi_device_state new_state);
+
+/* accessor functions for the SCSI parameters */
+static inline int scsi_device_sync(struct scsi_device *sdev)
+{
+	return sdev->sdtr;
+}
+static inline int scsi_device_wide(struct scsi_device *sdev)
+{
+	return sdev->wdtr;
+}
+static inline int scsi_device_dt(struct scsi_device *sdev)
+{
+	return sdev->ppr;
+}
+static inline int scsi_device_dt_only(struct scsi_device *sdev)
+{
+	if (sdev->inquiry_len < 57)
+		return 0;
+	return (sdev->inquiry[56] & 0x0c) == 0x04;
+}
+static inline int scsi_device_ius(struct scsi_device *sdev)
+{
+	if (sdev->inquiry_len < 57)
+		return 0;
+	return sdev->inquiry[56] & 0x01;
+}
+static inline int scsi_device_qas(struct scsi_device *sdev)
+{
+	if (sdev->inquiry_len < 57)
+		return 0;
+	return sdev->inquiry[56] & 0x02;
+}
+static inline int scsi_device_enclosure(struct scsi_device *sdev)
+{
+	return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
+}
+
+static inline int scsi_device_protection(struct scsi_device *sdev)
+{
+	if (sdev->no_dif)
+		return 0;
+
+	return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
+}
+
+static inline int scsi_device_tpgs(struct scsi_device *sdev)
+{
+	return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
+}
+
+/**
+ * scsi_device_supports_vpd - test if a device supports VPD pages
+ * @sdev: the &struct scsi_device to test
+ *
+ * If the 'try_vpd_pages' flag is set it takes precedence.
+ * Otherwise we will assume VPD pages are supported if the
+ * SCSI level is at least SPC-3 and 'skip_vpd_pages' is not set.
+ */
+static inline int scsi_device_supports_vpd(struct scsi_device *sdev)
+{
+	/* Attempt VPD inquiry if the device blacklist explicitly calls
+	 * for it.
+	 */
+	if (sdev->try_vpd_pages)
+		return 1;
+	/*
+	 * Although VPD inquiries can go to SCSI-2 type devices,
+	 * some USB ones crash on receiving them, and the pages
+	 * we currently ask for are mandatory for SPC-2 and beyond
+	 */
+	if (sdev->scsi_level >= SCSI_SPC_2 && !sdev->skip_vpd_pages)
+		return 1;
+	return 0;
+}
+
+static inline int scsi_device_busy(struct scsi_device *sdev)
+{
+	return sbitmap_weight(&sdev->budget_map);
+}
+
+#define MODULE_ALIAS_SCSI_DEVICE(type) \
+	MODULE_ALIAS("scsi:t-" __stringify(type) "*")
+#define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
+
+#endif /* _SCSI_SCSI_DEVICE_H */