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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /include/scsi/scsi_host.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/scsi/scsi_host.h')
-rw-r--r--include/scsi/scsi_host.h901
1 files changed, 901 insertions, 0 deletions
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
new file mode 100644
index 0000000000..4c2dc8150c
--- /dev/null
+++ b/include/scsi/scsi_host.h
@@ -0,0 +1,901 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _SCSI_SCSI_HOST_H
+#define _SCSI_SCSI_HOST_H
+
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+#include <linux/mutex.h>
+#include <linux/seq_file.h>
+#include <linux/blk-mq.h>
+#include <scsi/scsi.h>
+
+struct block_device;
+struct completion;
+struct module;
+struct scsi_cmnd;
+struct scsi_device;
+struct scsi_target;
+struct Scsi_Host;
+struct scsi_transport_template;
+
+
+#define SG_ALL SG_CHUNK_SIZE
+
+#define MODE_UNKNOWN 0x00
+#define MODE_INITIATOR 0x01
+#define MODE_TARGET 0x02
+
+/**
+ * enum scsi_timeout_action - How to handle a command that timed out.
+ * @SCSI_EH_DONE: The command has already been completed.
+ * @SCSI_EH_RESET_TIMER: Reset the timer and continue waiting for completion.
+ * @SCSI_EH_NOT_HANDLED: The command has not yet finished. Abort the command.
+ */
+enum scsi_timeout_action {
+ SCSI_EH_DONE,
+ SCSI_EH_RESET_TIMER,
+ SCSI_EH_NOT_HANDLED,
+};
+
+struct scsi_host_template {
+ /*
+ * Put fields referenced in IO submission path together in
+ * same cacheline
+ */
+
+ /*
+ * Additional per-command data allocated for the driver.
+ */
+ unsigned int cmd_size;
+
+ /*
+ * The queuecommand function is used to queue up a scsi
+ * command block to the LLDD. When the driver finished
+ * processing the command the done callback is invoked.
+ *
+ * If queuecommand returns 0, then the driver has accepted the
+ * command. It must also push it to the HBA if the scsi_cmnd
+ * flag SCMD_LAST is set, or if the driver does not implement
+ * commit_rqs. The done() function must be called on the command
+ * when the driver has finished with it. (you may call done on the
+ * command before queuecommand returns, but in this case you
+ * *must* return 0 from queuecommand).
+ *
+ * Queuecommand may also reject the command, in which case it may
+ * not touch the command and must not call done() for it.
+ *
+ * There are two possible rejection returns:
+ *
+ * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
+ * allow commands to other devices serviced by this host.
+ *
+ * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
+ * host temporarily.
+ *
+ * For compatibility, any other non-zero return is treated the
+ * same as SCSI_MLQUEUE_HOST_BUSY.
+ *
+ * NOTE: "temporarily" means either until the next command for#
+ * this device/host completes, or a period of time determined by
+ * I/O pressure in the system if there are no other outstanding
+ * commands.
+ *
+ * STATUS: REQUIRED
+ */
+ int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
+
+ /*
+ * The commit_rqs function is used to trigger a hardware
+ * doorbell after some requests have been queued with
+ * queuecommand, when an error is encountered before sending
+ * the request with SCMD_LAST set.
+ *
+ * STATUS: OPTIONAL
+ */
+ void (*commit_rqs)(struct Scsi_Host *, u16);
+
+ struct module *module;
+ const char *name;
+
+ /*
+ * The info function will return whatever useful information the
+ * developer sees fit. If not provided, then the name field will
+ * be used instead.
+ *
+ * Status: OPTIONAL
+ */
+ const char *(*info)(struct Scsi_Host *);
+
+ /*
+ * Ioctl interface
+ *
+ * Status: OPTIONAL
+ */
+ int (*ioctl)(struct scsi_device *dev, unsigned int cmd,
+ void __user *arg);
+
+
+#ifdef CONFIG_COMPAT
+ /*
+ * Compat handler. Handle 32bit ABI.
+ * When unknown ioctl is passed return -ENOIOCTLCMD.
+ *
+ * Status: OPTIONAL
+ */
+ int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,
+ void __user *arg);
+#endif
+
+ int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
+ int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
+
+ /*
+ * This is an error handling strategy routine. You don't need to
+ * define one of these if you don't want to - there is a default
+ * routine that is present that should work in most cases. For those
+ * driver authors that have the inclination and ability to write their
+ * own strategy routine, this is where it is specified. Note - the
+ * strategy routine is *ALWAYS* run in the context of the kernel eh
+ * thread. Thus you are guaranteed to *NOT* be in an interrupt
+ * handler when you execute this, and you are also guaranteed to
+ * *NOT* have any other commands being queued while you are in the
+ * strategy routine. When you return from this function, operations
+ * return to normal.
+ *
+ * See scsi_error.c scsi_unjam_host for additional comments about
+ * what this function should and should not be attempting to do.
+ *
+ * Status: REQUIRED (at least one of them)
+ */
+ int (* eh_abort_handler)(struct scsi_cmnd *);
+ int (* eh_device_reset_handler)(struct scsi_cmnd *);
+ int (* eh_target_reset_handler)(struct scsi_cmnd *);
+ int (* eh_bus_reset_handler)(struct scsi_cmnd *);
+ int (* eh_host_reset_handler)(struct scsi_cmnd *);
+
+ /*
+ * Before the mid layer attempts to scan for a new device where none
+ * currently exists, it will call this entry in your driver. Should
+ * your driver need to allocate any structs or perform any other init
+ * items in order to send commands to a currently unused target/lun
+ * combo, then this is where you can perform those allocations. This
+ * is specifically so that drivers won't have to perform any kind of
+ * "is this a new device" checks in their queuecommand routine,
+ * thereby making the hot path a bit quicker.
+ *
+ * Return values: 0 on success, non-0 on failure
+ *
+ * Deallocation: If we didn't find any devices at this ID, you will
+ * get an immediate call to slave_destroy(). If we find something
+ * here then you will get a call to slave_configure(), then the
+ * device will be used for however long it is kept around, then when
+ * the device is removed from the system (or * possibly at reboot
+ * time), you will then get a call to slave_destroy(). This is
+ * assuming you implement slave_configure and slave_destroy.
+ * However, if you allocate memory and hang it off the device struct,
+ * then you must implement the slave_destroy() routine at a minimum
+ * in order to avoid leaking memory
+ * each time a device is tore down.
+ *
+ * Status: OPTIONAL
+ */
+ int (* slave_alloc)(struct scsi_device *);
+
+ /*
+ * Once the device has responded to an INQUIRY and we know the
+ * device is online, we call into the low level driver with the
+ * struct scsi_device *. If the low level device driver implements
+ * this function, it *must* perform the task of setting the queue
+ * depth on the device. All other tasks are optional and depend
+ * on what the driver supports and various implementation details.
+ *
+ * Things currently recommended to be handled at this time include:
+ *
+ * 1. Setting the device queue depth. Proper setting of this is
+ * described in the comments for scsi_change_queue_depth.
+ * 2. Determining if the device supports the various synchronous
+ * negotiation protocols. The device struct will already have
+ * responded to INQUIRY and the results of the standard items
+ * will have been shoved into the various device flag bits, eg.
+ * device->sdtr will be true if the device supports SDTR messages.
+ * 3. Allocating command structs that the device will need.
+ * 4. Setting the default timeout on this device (if needed).
+ * 5. Anything else the low level driver might want to do on a device
+ * specific setup basis...
+ * 6. Return 0 on success, non-0 on error. The device will be marked
+ * as offline on error so that no access will occur. If you return
+ * non-0, your slave_destroy routine will never get called for this
+ * device, so don't leave any loose memory hanging around, clean
+ * up after yourself before returning non-0
+ *
+ * Status: OPTIONAL
+ */
+ int (* slave_configure)(struct scsi_device *);
+
+ /*
+ * Immediately prior to deallocating the device and after all activity
+ * has ceased the mid layer calls this point so that the low level
+ * driver may completely detach itself from the scsi device and vice
+ * versa. The low level driver is responsible for freeing any memory
+ * it allocated in the slave_alloc or slave_configure calls.
+ *
+ * Status: OPTIONAL
+ */
+ void (* slave_destroy)(struct scsi_device *);
+
+ /*
+ * Before the mid layer attempts to scan for a new device attached
+ * to a target where no target currently exists, it will call this
+ * entry in your driver. Should your driver need to allocate any
+ * structs or perform any other init items in order to send commands
+ * to a currently unused target, then this is where you can perform
+ * those allocations.
+ *
+ * Return values: 0 on success, non-0 on failure
+ *
+ * Status: OPTIONAL
+ */
+ int (* target_alloc)(struct scsi_target *);
+
+ /*
+ * Immediately prior to deallocating the target structure, and
+ * after all activity to attached scsi devices has ceased, the
+ * midlayer calls this point so that the driver may deallocate
+ * and terminate any references to the target.
+ *
+ * Status: OPTIONAL
+ */
+ void (* target_destroy)(struct scsi_target *);
+
+ /*
+ * If a host has the ability to discover targets on its own instead
+ * of scanning the entire bus, it can fill in this function and
+ * call scsi_scan_host(). This function will be called periodically
+ * until it returns 1 with the scsi_host and the elapsed time of
+ * the scan in jiffies.
+ *
+ * Status: OPTIONAL
+ */
+ int (* scan_finished)(struct Scsi_Host *, unsigned long);
+
+ /*
+ * If the host wants to be called before the scan starts, but
+ * after the midlayer has set up ready for the scan, it can fill
+ * in this function.
+ *
+ * Status: OPTIONAL
+ */
+ void (* scan_start)(struct Scsi_Host *);
+
+ /*
+ * Fill in this function to allow the queue depth of this host
+ * to be changeable (on a per device basis). Returns either
+ * the current queue depth setting (may be different from what
+ * was passed in) or an error. An error should only be
+ * returned if the requested depth is legal but the driver was
+ * unable to set it. If the requested depth is illegal, the
+ * driver should set and return the closest legal queue depth.
+ *
+ * Status: OPTIONAL
+ */
+ int (* change_queue_depth)(struct scsi_device *, int);
+
+ /*
+ * This functions lets the driver expose the queue mapping
+ * to the block layer.
+ *
+ * Status: OPTIONAL
+ */
+ void (* map_queues)(struct Scsi_Host *shost);
+
+ /*
+ * SCSI interface of blk_poll - poll for IO completions.
+ * Only applicable if SCSI LLD exposes multiple h/w queues.
+ *
+ * Return value: Number of completed entries found.
+ *
+ * Status: OPTIONAL
+ */
+ int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num);
+
+ /*
+ * Check if scatterlists need to be padded for DMA draining.
+ *
+ * Status: OPTIONAL
+ */
+ bool (* dma_need_drain)(struct request *rq);
+
+ /*
+ * This function determines the BIOS parameters for a given
+ * harddisk. These tend to be numbers that are made up by
+ * the host adapter. Parameters:
+ * size, device, list (heads, sectors, cylinders)
+ *
+ * Status: OPTIONAL
+ */
+ int (* bios_param)(struct scsi_device *, struct block_device *,
+ sector_t, int []);
+
+ /*
+ * This function is called when one or more partitions on the
+ * device reach beyond the end of the device.
+ *
+ * Status: OPTIONAL
+ */
+ void (*unlock_native_capacity)(struct scsi_device *);
+
+ /*
+ * Can be used to export driver statistics and other infos to the
+ * world outside the kernel ie. userspace and it also provides an
+ * interface to feed the driver with information.
+ *
+ * Status: OBSOLETE
+ */
+ int (*show_info)(struct seq_file *, struct Scsi_Host *);
+ int (*write_info)(struct Scsi_Host *, char *, int);
+
+ /*
+ * This is an optional routine that allows the transport to become
+ * involved when a scsi io timer fires. The return value tells the
+ * timer routine how to finish the io timeout handling.
+ *
+ * Status: OPTIONAL
+ */
+ enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *);
+ /*
+ * Optional routine that allows the transport to decide if a cmd
+ * is retryable. Return true if the transport is in a state the
+ * cmd should be retried on.
+ */
+ bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd);
+
+ /* This is an optional routine that allows transport to initiate
+ * LLD adapter or firmware reset using sysfs attribute.
+ *
+ * Return values: 0 on success, -ve value on failure.
+ *
+ * Status: OPTIONAL
+ */
+
+ int (*host_reset)(struct Scsi_Host *shost, int reset_type);
+#define SCSI_ADAPTER_RESET 1
+#define SCSI_FIRMWARE_RESET 2
+
+
+ /*
+ * Name of proc directory
+ */
+ const char *proc_name;
+
+ /*
+ * This determines if we will use a non-interrupt driven
+ * or an interrupt driven scheme. It is set to the maximum number
+ * of simultaneous commands a single hw queue in HBA will accept.
+ */
+ int can_queue;
+
+ /*
+ * In many instances, especially where disconnect / reconnect are
+ * supported, our host also has an ID on the SCSI bus. If this is
+ * the case, then it must be reserved. Please set this_id to -1 if
+ * your setup is in single initiator mode, and the host lacks an
+ * ID.
+ */
+ int this_id;
+
+ /*
+ * This determines the degree to which the host adapter is capable
+ * of scatter-gather.
+ */
+ unsigned short sg_tablesize;
+ unsigned short sg_prot_tablesize;
+
+ /*
+ * Set this if the host adapter has limitations beside segment count.
+ */
+ unsigned int max_sectors;
+
+ /*
+ * Maximum size in bytes of a single segment.
+ */
+ unsigned int max_segment_size;
+
+ /*
+ * DMA scatter gather segment boundary limit. A segment crossing this
+ * boundary will be split in two.
+ */
+ unsigned long dma_boundary;
+
+ unsigned long virt_boundary_mask;
+
+ /*
+ * This specifies "machine infinity" for host templates which don't
+ * limit the transfer size. Note this limit represents an absolute
+ * maximum, and may be over the transfer limits allowed for
+ * individual devices (e.g. 256 for SCSI-1).
+ */
+#define SCSI_DEFAULT_MAX_SECTORS 1024
+
+ /*
+ * True if this host adapter can make good use of linked commands.
+ * This will allow more than one command to be queued to a given
+ * unit on a given host. Set this to the maximum number of command
+ * blocks to be provided for each device. Set this to 1 for one
+ * command block per lun, 2 for two, etc. Do not set this to 0.
+ * You should make sure that the host adapter will do the right thing
+ * before you try setting this above 1.
+ */
+ short cmd_per_lun;
+
+ /* If use block layer to manage tags, this is tag allocation policy */
+ int tag_alloc_policy;
+
+ /*
+ * Track QUEUE_FULL events and reduce queue depth on demand.
+ */
+ unsigned track_queue_depth:1;
+
+ /*
+ * This specifies the mode that a LLD supports.
+ */
+ unsigned supported_mode:2;
+
+ /*
+ * True for emulated SCSI host adapters (e.g. ATAPI).
+ */
+ unsigned emulated:1;
+
+ /*
+ * True if the low-level driver performs its own reset-settle delays.
+ */
+ unsigned skip_settle_delay:1;
+
+ /* True if the controller does not support WRITE SAME */
+ unsigned no_write_same:1;
+
+ /* True if the host uses host-wide tagspace */
+ unsigned host_tagset:1;
+
+ /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
+ unsigned queuecommand_may_block:1;
+
+ /*
+ * Countdown for host blocking with no commands outstanding.
+ */
+ unsigned int max_host_blocked;
+
+ /*
+ * Default value for the blocking. If the queue is empty,
+ * host_blocked counts down in the request_fn until it restarts
+ * host operations as zero is reached.
+ *
+ * FIXME: This should probably be a value in the template
+ */
+#define SCSI_DEFAULT_HOST_BLOCKED 7
+
+ /*
+ * Pointer to the SCSI host sysfs attribute groups, NULL terminated.
+ */
+ const struct attribute_group **shost_groups;
+
+ /*
+ * Pointer to the SCSI device attribute groups for this host,
+ * NULL terminated.
+ */
+ const struct attribute_group **sdev_groups;
+
+ /*
+ * Vendor Identifier associated with the host
+ *
+ * Note: When specifying vendor_id, be sure to read the
+ * Vendor Type and ID formatting requirements specified in
+ * scsi_netlink.h
+ */
+ u64 vendor_id;
+
+ /* Delay for runtime autosuspend */
+ int rpm_autosuspend_delay;
+};
+
+/*
+ * Temporary #define for host lock push down. Can be removed when all
+ * drivers have been updated to take advantage of unlocked
+ * queuecommand.
+ *
+ */
+#define DEF_SCSI_QCMD(func_name) \
+ int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
+ { \
+ unsigned long irq_flags; \
+ int rc; \
+ spin_lock_irqsave(shost->host_lock, irq_flags); \
+ rc = func_name##_lck(cmd); \
+ spin_unlock_irqrestore(shost->host_lock, irq_flags); \
+ return rc; \
+ }
+
+
+/*
+ * shost state: If you alter this, you also need to alter scsi_sysfs.c
+ * (for the ascii descriptions) and the state model enforcer:
+ * scsi_host_set_state()
+ */
+enum scsi_host_state {
+ SHOST_CREATED = 1,
+ SHOST_RUNNING,
+ SHOST_CANCEL,
+ SHOST_DEL,
+ SHOST_RECOVERY,
+ SHOST_CANCEL_RECOVERY,
+ SHOST_DEL_RECOVERY,
+};
+
+struct Scsi_Host {
+ /*
+ * __devices is protected by the host_lock, but you should
+ * usually use scsi_device_lookup / shost_for_each_device
+ * to access it and don't care about locking yourself.
+ * In the rare case of being in irq context you can use
+ * their __ prefixed variants with the lock held. NEVER
+ * access this list directly from a driver.
+ */
+ struct list_head __devices;
+ struct list_head __targets;
+
+ struct list_head starved_list;
+
+ spinlock_t default_lock;
+ spinlock_t *host_lock;
+
+ struct mutex scan_mutex;/* serialize scanning activity */
+
+ struct list_head eh_abort_list;
+ struct list_head eh_cmd_q;
+ struct task_struct * ehandler; /* Error recovery thread. */
+ struct completion * eh_action; /* Wait for specific actions on the
+ host. */
+ wait_queue_head_t host_wait;
+ const struct scsi_host_template *hostt;
+ struct scsi_transport_template *transportt;
+
+ struct kref tagset_refcnt;
+ struct completion tagset_freed;
+ /* Area to keep a shared tag map */
+ struct blk_mq_tag_set tag_set;
+
+ atomic_t host_blocked;
+
+ unsigned int host_failed; /* commands that failed.
+ protected by host_lock */
+ unsigned int host_eh_scheduled; /* EH scheduled without command */
+
+ unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
+
+ /* next two fields are used to bound the time spent in error handling */
+ int eh_deadline;
+ unsigned long last_reset;
+
+
+ /*
+ * These three parameters can be used to allow for wide scsi,
+ * and for host adapters that support multiple busses
+ * The last two should be set to 1 more than the actual max id
+ * or lun (e.g. 8 for SCSI parallel systems).
+ */
+ unsigned int max_channel;
+ unsigned int max_id;
+ u64 max_lun;
+
+ /*
+ * This is a unique identifier that must be assigned so that we
+ * have some way of identifying each detected host adapter properly
+ * and uniquely. For hosts that do not support more than one card
+ * in the system at one time, this does not need to be set. It is
+ * initialized to 0 in scsi_register.
+ */
+ unsigned int unique_id;
+
+ /*
+ * The maximum length of SCSI commands that this host can accept.
+ * Probably 12 for most host adapters, but could be 16 for others.
+ * or 260 if the driver supports variable length cdbs.
+ * For drivers that don't set this field, a value of 12 is
+ * assumed.
+ */
+ unsigned short max_cmd_len;
+
+ int this_id;
+ int can_queue;
+ short cmd_per_lun;
+ short unsigned int sg_tablesize;
+ short unsigned int sg_prot_tablesize;
+ unsigned int max_sectors;
+ unsigned int opt_sectors;
+ unsigned int max_segment_size;
+ unsigned long dma_boundary;
+ unsigned long virt_boundary_mask;
+ /*
+ * In scsi-mq mode, the number of hardware queues supported by the LLD.
+ *
+ * Note: it is assumed that each hardware queue has a queue depth of
+ * can_queue. In other words, the total queue depth per host
+ * is nr_hw_queues * can_queue. However, for when host_tagset is set,
+ * the total queue depth is can_queue.
+ */
+ unsigned nr_hw_queues;
+ unsigned nr_maps;
+ unsigned active_mode:2;
+
+ /*
+ * Host has requested that no further requests come through for the
+ * time being.
+ */
+ unsigned host_self_blocked:1;
+
+ /*
+ * Host uses correct SCSI ordering not PC ordering. The bit is
+ * set for the minority of drivers whose authors actually read
+ * the spec ;).
+ */
+ unsigned reverse_ordering:1;
+
+ /* Task mgmt function in progress */
+ unsigned tmf_in_progress:1;
+
+ /* Asynchronous scan in progress */
+ unsigned async_scan:1;
+
+ /* Don't resume host in EH */
+ unsigned eh_noresume:1;
+
+ /* The controller does not support WRITE SAME */
+ unsigned no_write_same:1;
+
+ /* True if the host uses host-wide tagspace */
+ unsigned host_tagset:1;
+
+ /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
+ unsigned queuecommand_may_block:1;
+
+ /* Host responded with short (<36 bytes) INQUIRY result */
+ unsigned short_inquiry:1;
+
+ /* The transport requires the LUN bits NOT to be stored in CDB[1] */
+ unsigned no_scsi2_lun_in_cdb:1;
+
+ /*
+ * Optional work queue to be utilized by the transport
+ */
+ char work_q_name[20];
+ struct workqueue_struct *work_q;
+
+ /*
+ * Task management function work queue
+ */
+ struct workqueue_struct *tmf_work_q;
+
+ /*
+ * Value host_blocked counts down from
+ */
+ unsigned int max_host_blocked;
+
+ /* Protection Information */
+ unsigned int prot_capabilities;
+ unsigned char prot_guard_type;
+
+ /* legacy crap */
+ unsigned long base;
+ unsigned long io_port;
+ unsigned char n_io_port;
+ unsigned char dma_channel;
+ unsigned int irq;
+
+
+ enum scsi_host_state shost_state;
+
+ /* ldm bits */
+ struct device shost_gendev, shost_dev;
+
+ /*
+ * Points to the transport data (if any) which is allocated
+ * separately
+ */
+ void *shost_data;
+
+ /*
+ * Points to the physical bus device we'd use to do DMA
+ * Needed just in case we have virtual hosts.
+ */
+ struct device *dma_dev;
+
+ /*
+ * We should ensure that this is aligned, both for better performance
+ * and also because some compilers (m68k) don't automatically force
+ * alignment to a long boundary.
+ */
+ unsigned long hostdata[] /* Used for storage of host specific stuff */
+ __attribute__ ((aligned (sizeof(unsigned long))));
+};
+
+#define class_to_shost(d) \
+ container_of(d, struct Scsi_Host, shost_dev)
+
+#define shost_printk(prefix, shost, fmt, a...) \
+ dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
+
+static inline void *shost_priv(struct Scsi_Host *shost)
+{
+ return (void *)shost->hostdata;
+}
+
+int scsi_is_host_device(const struct device *);
+
+static inline struct Scsi_Host *dev_to_shost(struct device *dev)
+{
+ while (!scsi_is_host_device(dev)) {
+ if (!dev->parent)
+ return NULL;
+ dev = dev->parent;
+ }
+ return container_of(dev, struct Scsi_Host, shost_gendev);
+}
+
+static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
+{
+ return shost->shost_state == SHOST_RECOVERY ||
+ shost->shost_state == SHOST_CANCEL_RECOVERY ||
+ shost->shost_state == SHOST_DEL_RECOVERY ||
+ shost->tmf_in_progress;
+}
+
+extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
+extern void scsi_flush_work(struct Scsi_Host *);
+
+extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int);
+extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
+ struct device *,
+ struct device *);
+#if defined(CONFIG_SCSI_PROC_FS)
+struct proc_dir_entry *
+scsi_template_proc_dir(const struct scsi_host_template *sht);
+#else
+#define scsi_template_proc_dir(sht) NULL
+#endif
+extern void scsi_scan_host(struct Scsi_Host *);
+extern int scsi_rescan_device(struct scsi_device *sdev);
+extern void scsi_remove_host(struct Scsi_Host *);
+extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
+extern int scsi_host_busy(struct Scsi_Host *shost);
+extern void scsi_host_put(struct Scsi_Host *t);
+extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum);
+extern const char *scsi_host_state_name(enum scsi_host_state);
+extern void scsi_host_complete_all_commands(struct Scsi_Host *shost,
+ enum scsi_host_status status);
+
+static inline int __must_check scsi_add_host(struct Scsi_Host *host,
+ struct device *dev)
+{
+ return scsi_add_host_with_dma(host, dev, dev);
+}
+
+static inline struct device *scsi_get_device(struct Scsi_Host *shost)
+{
+ return shost->shost_gendev.parent;
+}
+
+/**
+ * scsi_host_scan_allowed - Is scanning of this host allowed
+ * @shost: Pointer to Scsi_Host.
+ **/
+static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
+{
+ return shost->shost_state == SHOST_RUNNING ||
+ shost->shost_state == SHOST_RECOVERY;
+}
+
+extern void scsi_unblock_requests(struct Scsi_Host *);
+extern void scsi_block_requests(struct Scsi_Host *);
+extern int scsi_host_block(struct Scsi_Host *shost);
+extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);
+
+void scsi_host_busy_iter(struct Scsi_Host *,
+ bool (*fn)(struct scsi_cmnd *, void *), void *priv);
+
+struct class_container;
+
+/*
+ * DIF defines the exchange of protection information between
+ * initiator and SBC block device.
+ *
+ * DIX defines the exchange of protection information between OS and
+ * initiator.
+ */
+enum scsi_host_prot_capabilities {
+ SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
+ SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
+ SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
+
+ SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
+ SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
+ SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
+ SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
+};
+
+/*
+ * SCSI hosts which support the Data Integrity Extensions must
+ * indicate their capabilities by setting the prot_capabilities using
+ * this call.
+ */
+static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
+{
+ shost->prot_capabilities = mask;
+}
+
+static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
+{
+ return shost->prot_capabilities;
+}
+
+static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
+{
+ return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
+}
+
+static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
+{
+ static unsigned char cap[] = { 0,
+ SHOST_DIF_TYPE1_PROTECTION,
+ SHOST_DIF_TYPE2_PROTECTION,
+ SHOST_DIF_TYPE3_PROTECTION };
+
+ if (target_type >= ARRAY_SIZE(cap))
+ return 0;
+
+ return shost->prot_capabilities & cap[target_type] ? target_type : 0;
+}
+
+static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
+{
+#if defined(CONFIG_BLK_DEV_INTEGRITY)
+ static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
+ SHOST_DIX_TYPE1_PROTECTION,
+ SHOST_DIX_TYPE2_PROTECTION,
+ SHOST_DIX_TYPE3_PROTECTION };
+
+ if (target_type >= ARRAY_SIZE(cap))
+ return 0;
+
+ return shost->prot_capabilities & cap[target_type];
+#endif
+ return 0;
+}
+
+/*
+ * All DIX-capable initiators must support the T10-mandated CRC
+ * checksum. Controllers can optionally implement the IP checksum
+ * scheme which has much lower impact on system performance. Note
+ * that the main rationale for the checksum is to match integrity
+ * metadata with data. Detecting bit errors are a job for ECC memory
+ * and buses.
+ */
+
+enum scsi_host_guard_type {
+ SHOST_DIX_GUARD_CRC = 1 << 0,
+ SHOST_DIX_GUARD_IP = 1 << 1,
+};
+
+static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
+{
+ shost->prot_guard_type = type;
+}
+
+static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
+{
+ return shost->prot_guard_type;
+}
+
+extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
+
+#endif /* _SCSI_SCSI_HOST_H */