Added scsi_tgt kernel module source code.

git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@2156 d57e44dd-8a1f-0410-8b47-8ef2f437770f
This commit is contained in:
Bart Van Assche
2010-09-22 17:00:46 +00:00
parent 14638a27a5
commit 20098b3634
17 changed files with 3542 additions and 1 deletions

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@@ -3,7 +3,9 @@ EXTRA_CFLAGS += -DCONFIG_SCST_TRACING
EXTRA_CFLAGS += -DCONFIG_SCST_DEBUG
#EXTRA_CFLAGS += -g -fno-inline -fno-inline-functions
EXTRA_CFLAGS += -DCONFIG_SCST_EXTRACHECKS
EXTRA_CFLAGS += -Wextra -Wno-unused-parameter
#EXTRA_CFLAGS += -Wextra -Wno-unused-parameter
obj-m += ibmvstgt.o
obj-m += libsrpnew.o
scsi_tgt-y += scsi_tgt_lib.o scsi_tgt_if.o

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@@ -0,0 +1,878 @@
#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 <scsi/scsi.h>
struct request_queue;
struct block_device;
struct completion;
struct module;
struct scsi_cmnd;
struct scsi_device;
struct scsi_target;
struct Scsi_Host;
struct scsi_host_cmd_pool;
struct scsi_transport_template;
struct blk_queue_tags;
/*
* The various choices mean:
* NONE: Self evident. Host adapter is not capable of scatter-gather.
* ALL: Means that the host adapter module can do scatter-gather,
* and that there is no limit to the size of the table to which
* we scatter/gather data. The value we set here is the maximum
* single element sglist. To use chained sglists, the adapter
* has to set a value beyond ALL (and correctly use the chain
* handling API.
* Anything else: Indicates the maximum number of chains that can be
* used in one scatter-gather request.
*/
#define SG_NONE 0
#define SG_ALL SCSI_MAX_SG_SEGMENTS
#define MODE_UNKNOWN 0x00
#define MODE_INITIATOR 0x01
#define MODE_TARGET 0x02
#define DISABLE_CLUSTERING 0
#define ENABLE_CLUSTERING 1
enum {
SCSI_QDEPTH_DEFAULT, /* default requested change, e.g. from sysfs */
SCSI_QDEPTH_QFULL, /* scsi-ml requested due to queue full */
SCSI_QDEPTH_RAMP_UP, /* scsi-ml requested due to threshhold event */
};
struct scsi_host_template {
struct module *module;
const char *name;
/*
* Used to initialize old-style drivers. For new-style drivers
* just perform all work in your module initialization function.
*
* Status: OBSOLETE
*/
int (* detect)(struct scsi_host_template *);
/*
* Used as unload callback for hosts with old-style drivers.
*
* Status: OBSOLETE
*/
int (* release)(struct Scsi_Host *);
/*
* 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, 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, int cmd, void __user *arg);
#endif
/*
* 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 HBA has accepted the
* command. 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_cmnd *,
void (*done)(struct scsi_cmnd *));
/*
* The transfer functions are used to queue a scsi command to
* the LLD. When the driver is finished processing the command
* the done callback is invoked.
*
* This is called to inform the LLD to transfer
* scsi_bufflen(cmd) bytes. scsi_sg_count(cmd) speciefies the
* number of scatterlist entried in the command and
* scsi_sglist(cmd) returns the scatterlist.
*
* return values: see queuecommand
*
* If the LLD accepts the cmd, it should set the result to an
* appropriate value when completed before calling the done function.
*
* STATUS: REQUIRED FOR TARGET DRIVERS
*/
/* TODO: rename */
int (* transfer_response)(struct scsi_cmnd *,
void (*done)(struct scsi_cmnd *));
/*
* 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_adjust_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, int);
/*
* Fill in this function to allow the changing of tag types
* (this also allows the enabling/disabling of tag command
* queueing). An error should only be returned if something
* went wrong in the driver while trying to set the tag type.
* If the driver doesn't support the requested tag type, then
* it should set the closest type it does support without
* returning an error. Returns the actual tag type set.
*
* Status: OPTIONAL
*/
int (* change_queue_type)(struct scsi_device *, int);
/*
* 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 (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, 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:
* EH_HANDLED: I fixed the error, please complete the command
* EH_RESET_TIMER: I need more time, reset the timer and
* begin counting again
* EH_NOT_HANDLED Begin normal error recovery
*
* Status: OPTIONAL
*/
enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
/*
* Name of proc directory
*/
const char *proc_name;
/*
* Used to store the procfs directory if a driver implements the
* proc_info method.
*/
struct proc_dir_entry *proc_dir;
/*
* 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 given host adapter 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;
/*
* Set this if the host adapter has limitations beside segment count.
*/
unsigned short max_sectors;
/*
* DMA scatter gather segment boundary limit. A segment crossing this
* boundary will be split in two.
*/
unsigned long dma_boundary;
/*
* 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;
/*
* present contains counter indicating how many boards of this
* type were found when we did the scan.
*/
unsigned char present;
/*
* This specifies the mode that a LLD supports.
*/
unsigned supported_mode:2;
/*
* True if this host adapter uses unchecked DMA onto an ISA bus.
*/
unsigned unchecked_isa_dma:1;
/*
* True if this host adapter can make good use of clustering.
* I originally thought that if the tablesize was large that it
* was a waste of CPU cycles to prepare a cluster list, but
* it works out that the Buslogic is faster if you use a smaller
* number of segments (i.e. use clustering). I guess it is
* inefficient.
*/
unsigned use_clustering:1;
/*
* 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 we are using ordered write support.
*/
unsigned ordered_tag: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 sysfs class properties for this host, NULL terminated.
*/
struct device_attribute **shost_attrs;
/*
* Pointer to the SCSI device properties for this host, NULL terminated.
*/
struct device_attribute **sdev_attrs;
/*
* List of hosts per template.
*
* This is only for use by scsi_module.c for legacy templates.
* For these access to it is synchronized implicitly by
* module_init/module_exit.
*/
struct list_head legacy_hosts;
/*
* 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;
};
/*
* 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 beeing 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 scsi_host_cmd_pool *cmd_pool;
spinlock_t free_list_lock;
struct list_head free_list; /* backup store of cmd structs */
struct list_head starved_list;
spinlock_t default_lock;
spinlock_t *host_lock;
struct mutex scan_mutex;/* serialize scanning activity */
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;
struct scsi_host_template *hostt;
struct scsi_transport_template *transportt;
/*
* Area to keep a shared tag map (if needed, will be
* NULL if not).
*/
struct blk_queue_tag *bqt;
/*
* The following two fields are protected with host_lock;
* however, eh routines can safely access during eh processing
* without acquiring the lock.
*/
unsigned int host_busy; /* commands actually active on low-level */
unsigned int host_failed; /* commands that failed. */
unsigned int host_eh_scheduled; /* EH scheduled without command */
unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
int resetting; /* if set, it means that last_reset is a valid value */
unsigned long last_reset;
/*
* These three parameters can be used to allow for wide scsi,
* and for host adapters that support multiple busses
* The first two should be set to 1 more than the actual max id
* or lun (i.e. 8 for normal systems).
*/
unsigned int max_id;
unsigned int max_lun;
unsigned int max_channel;
/*
* 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 max_sectors;
unsigned long dma_boundary;
/*
* Used to assign serial numbers to the cmds.
* Protected by the host lock.
*/
unsigned long cmd_serial_number;
unsigned active_mode:2;
unsigned unchecked_isa_dma:1;
unsigned use_clustering:1;
unsigned use_blk_tcq:1;
/*
* 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;
/*
* Ordered write support
*/
unsigned ordered_tag:1;
/* Task mgmt function in progress */
unsigned tmf_in_progress:1;
/* Asynchronous scan in progress */
unsigned async_scan:1;
/*
* Optional work queue to be utilized by the transport
*/
char work_q_name[20];
struct workqueue_struct *work_q;
/*
* Host has rejected a command because it was busy.
*/
unsigned int host_blocked;
/*
* Value host_blocked counts down from
*/
unsigned int max_host_blocked;
/* Protection Information */
unsigned int prot_capabilities;
unsigned char prot_guard_type;
/*
* q used for scsi_tgt msgs, async events or any other requests that
* need to be processed in userspace
*/
struct request_queue *uspace_req_q;
/* 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;
/*
* List of hosts per template.
*
* This is only for use by scsi_module.c for legacy templates.
* For these access to it is synchronized implicitly by
* module_init/module_exit.
*/
struct list_head sht_legacy_list;
/*
* 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[0] /* 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(struct scsi_host_template *, int);
extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
struct device *,
struct device *);
extern void scsi_scan_host(struct Scsi_Host *);
extern void scsi_rescan_device(struct device *);
extern void scsi_remove_host(struct Scsi_Host *);
extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
extern void scsi_host_put(struct Scsi_Host *t);
extern struct Scsi_Host *scsi_host_lookup(unsigned short);
extern const char *scsi_host_state_name(enum scsi_host_state);
extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *);
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;
}
extern void scsi_unblock_requests(struct Scsi_Host *);
extern void scsi_block_requests(struct Scsi_Host *);
struct class_container;
extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
void (*) (struct request_queue *));
/*
* These two functions are used to allocate and free a pseudo device
* which will connect to the host adapter itself rather than any
* physical device. You must deallocate when you are done with the
* thing. This physical pseudo-device isn't real and won't be available
* from any high-level drivers.
*/
extern void scsi_free_host_dev(struct scsi_device *);
extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
/*
* 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 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 };
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 };
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;
}
/* legacy interfaces */
extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
extern void scsi_unregister(struct Scsi_Host *);
extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
#endif /* _SCSI_SCSI_HOST_H */

View File

@@ -0,0 +1,21 @@
/*
* SCSI target definitions
*/
#include <linux/dma-mapping.h>
struct Scsi_Host;
struct scsi_cmnd;
struct scsi_lun;
extern struct Scsi_Host *scsi_tgt_cmd_to_host(struct scsi_cmnd *);
extern int scsi_tgt_alloc_queue(struct Scsi_Host *);
extern void scsi_tgt_free_queue(struct Scsi_Host *);
extern int scsi_tgt_queue_command(struct scsi_cmnd *, u64, struct scsi_lun *, u64);
extern int scsi_tgt_tsk_mgmt_request(struct Scsi_Host *, u64, int, u64,
struct scsi_lun *, void *);
extern struct scsi_cmnd *scsi_host_get_command(struct Scsi_Host *,
enum dma_data_direction, gfp_t);
extern void scsi_host_put_command(struct Scsi_Host *, struct scsi_cmnd *);
extern int scsi_tgt_it_nexus_create(struct Scsi_Host *, u64, char *);
extern int scsi_tgt_it_nexus_destroy(struct Scsi_Host *, u64);

View File

@@ -0,0 +1,399 @@
/*
* SCSI target kernel/user interface functions
*
* Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org>
* Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/miscdevice.h>
#include <linux/gfp.h>
#include <linux/file.h>
#include <linux/smp_lock.h>
#include <net/tcp.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tgt.h>
#include <scsi/scsi_tgt_if.h>
#include <asm/cacheflush.h>
#include "scsi_tgt_priv.h"
#if TGT_RING_SIZE < PAGE_SIZE
# define TGT_RING_SIZE PAGE_SIZE
#endif
#define TGT_RING_PAGES (TGT_RING_SIZE >> PAGE_SHIFT)
#define TGT_EVENT_PER_PAGE (PAGE_SIZE / sizeof(struct tgt_event))
#define TGT_MAX_EVENTS (TGT_EVENT_PER_PAGE * TGT_RING_PAGES)
struct tgt_ring {
u32 tr_idx;
unsigned long tr_pages[TGT_RING_PAGES];
spinlock_t tr_lock;
};
/* tx_ring : kernel->user, rx_ring : user->kernel */
static struct tgt_ring tx_ring, rx_ring;
static DECLARE_WAIT_QUEUE_HEAD(tgt_poll_wait);
static inline void tgt_ring_idx_inc(struct tgt_ring *ring)
{
if (ring->tr_idx == TGT_MAX_EVENTS - 1)
ring->tr_idx = 0;
else
ring->tr_idx++;
}
static struct tgt_event *tgt_head_event(struct tgt_ring *ring, u32 idx)
{
u32 pidx, off;
pidx = idx / TGT_EVENT_PER_PAGE;
off = idx % TGT_EVENT_PER_PAGE;
return (struct tgt_event *)
(ring->tr_pages[pidx] + sizeof(struct tgt_event) * off);
}
static int tgt_uspace_send_event(u32 type, struct tgt_event *p)
{
struct tgt_event *ev;
struct tgt_ring *ring = &tx_ring;
unsigned long flags;
int err = 0;
spin_lock_irqsave(&ring->tr_lock, flags);
ev = tgt_head_event(ring, ring->tr_idx);
if (!ev->hdr.status)
tgt_ring_idx_inc(ring);
else
err = -BUSY;
spin_unlock_irqrestore(&ring->tr_lock, flags);
if (err)
return err;
memcpy(ev, p, sizeof(*ev));
ev->hdr.type = type;
mb();
ev->hdr.status = 1;
flush_dcache_page(virt_to_page(ev));
wake_up_interruptible(&tgt_poll_wait);
return 0;
}
int scsi_tgt_uspace_send_cmd(struct scsi_cmnd *cmd, u64 itn_id,
struct scsi_lun *lun, u64 tag)
{
struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd);
struct tgt_event ev;
int err;
memset(&ev, 0, sizeof(ev));
ev.p.cmd_req.host_no = shost->host_no;
ev.p.cmd_req.itn_id = itn_id;
ev.p.cmd_req.data_len = scsi_bufflen(cmd);
memcpy(ev.p.cmd_req.scb, cmd->cmnd, sizeof(ev.p.cmd_req.scb));
memcpy(ev.p.cmd_req.lun, lun, sizeof(ev.p.cmd_req.lun));
ev.p.cmd_req.attribute = cmd->tag;
ev.p.cmd_req.tag = tag;
dprintk("%p %d %u %x %llx\n", cmd, shost->host_no,
ev.p.cmd_req.data_len, cmd->tag,
(unsigned long long) ev.p.cmd_req.tag);
err = tgt_uspace_send_event(TGT_KEVENT_CMD_REQ, &ev);
if (err)
eprintk("tx buf is full, could not send\n");
return err;
}
int scsi_tgt_uspace_send_status(struct scsi_cmnd *cmd, u64 itn_id, u64 tag)
{
struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd);
struct tgt_event ev;
int err;
memset(&ev, 0, sizeof(ev));
ev.p.cmd_done.host_no = shost->host_no;
ev.p.cmd_done.itn_id = itn_id;
ev.p.cmd_done.tag = tag;
ev.p.cmd_done.result = cmd->result;
dprintk("%p %d %llu %u %x\n", cmd, shost->host_no,
(unsigned long long) ev.p.cmd_req.tag,
ev.p.cmd_req.data_len, cmd->tag);
err = tgt_uspace_send_event(TGT_KEVENT_CMD_DONE, &ev);
if (err)
eprintk("tx buf is full, could not send\n");
return err;
}
int scsi_tgt_uspace_send_tsk_mgmt(int host_no, u64 itn_id, int function,
u64 tag, struct scsi_lun *scsilun, void *data)
{
struct tgt_event ev;
int err;
memset(&ev, 0, sizeof(ev));
ev.p.tsk_mgmt_req.host_no = host_no;
ev.p.tsk_mgmt_req.itn_id = itn_id;
ev.p.tsk_mgmt_req.function = function;
ev.p.tsk_mgmt_req.tag = tag;
memcpy(ev.p.tsk_mgmt_req.lun, scsilun, sizeof(ev.p.tsk_mgmt_req.lun));
ev.p.tsk_mgmt_req.mid = (u64) (unsigned long) data;
dprintk("%d %x %llx %llx\n", host_no, function, (unsigned long long) tag,
(unsigned long long) ev.p.tsk_mgmt_req.mid);
err = tgt_uspace_send_event(TGT_KEVENT_TSK_MGMT_REQ, &ev);
if (err)
eprintk("tx buf is full, could not send\n");
return err;
}
int scsi_tgt_uspace_send_it_nexus_request(int host_no, u64 itn_id,
int function, char *initiator_id)
{
struct tgt_event ev;
int err;
memset(&ev, 0, sizeof(ev));
ev.p.it_nexus_req.host_no = host_no;
ev.p.it_nexus_req.function = function;
ev.p.it_nexus_req.itn_id = itn_id;
if (initiator_id)
strncpy(ev.p.it_nexus_req.initiator_id, initiator_id,
sizeof(ev.p.it_nexus_req.initiator_id));
dprintk("%d %x %llx\n", host_no, function, (unsigned long long)itn_id);
err = tgt_uspace_send_event(TGT_KEVENT_IT_NEXUS_REQ, &ev);
if (err)
eprintk("tx buf is full, could not send\n");
return err;
}
static int event_recv_msg(struct tgt_event *ev)
{
int err = 0;
switch (ev->hdr.type) {
case TGT_UEVENT_CMD_RSP:
err = scsi_tgt_kspace_exec(ev->p.cmd_rsp.host_no,
ev->p.cmd_rsp.itn_id,
ev->p.cmd_rsp.result,
ev->p.cmd_rsp.tag,
ev->p.cmd_rsp.uaddr,
ev->p.cmd_rsp.len,
ev->p.cmd_rsp.sense_uaddr,
ev->p.cmd_rsp.sense_len,
ev->p.cmd_rsp.rw);
break;
case TGT_UEVENT_TSK_MGMT_RSP:
err = scsi_tgt_kspace_tsk_mgmt(ev->p.tsk_mgmt_rsp.host_no,
ev->p.tsk_mgmt_rsp.itn_id,
ev->p.tsk_mgmt_rsp.mid,
ev->p.tsk_mgmt_rsp.result);
break;
case TGT_UEVENT_IT_NEXUS_RSP:
err = scsi_tgt_kspace_it_nexus_rsp(ev->p.it_nexus_rsp.host_no,
ev->p.it_nexus_rsp.itn_id,
ev->p.it_nexus_rsp.result);
break;
default:
eprintk("unknown type %d\n", ev->hdr.type);
err = -EINVAL;
}
return err;
}
static ssize_t tgt_write(struct file *file, const char __user * buffer,
size_t count, loff_t * ppos)
{
struct tgt_event *ev;
struct tgt_ring *ring = &rx_ring;
while (1) {
ev = tgt_head_event(ring, ring->tr_idx);
/* do we need this? */
flush_dcache_page(virt_to_page(ev));
if (!ev->hdr.status)
break;
tgt_ring_idx_inc(ring);
event_recv_msg(ev);
ev->hdr.status = 0;
};
return count;
}
static unsigned int tgt_poll(struct file * file, struct poll_table_struct *wait)
{
struct tgt_event *ev;
struct tgt_ring *ring = &tx_ring;
unsigned long flags;
unsigned int mask = 0;
u32 idx;
poll_wait(file, &tgt_poll_wait, wait);
spin_lock_irqsave(&ring->tr_lock, flags);
idx = ring->tr_idx ? ring->tr_idx - 1 : TGT_MAX_EVENTS - 1;
ev = tgt_head_event(ring, idx);
if (ev->hdr.status)
mask |= POLLIN | POLLRDNORM;
spin_unlock_irqrestore(&ring->tr_lock, flags);
return mask;
}
static int uspace_ring_map(struct vm_area_struct *vma, unsigned long addr,
struct tgt_ring *ring)
{
int i, err;
for (i = 0; i < TGT_RING_PAGES; i++) {
struct page *page = virt_to_page(ring->tr_pages[i]);
err = vm_insert_page(vma, addr, page);
if (err)
return err;
addr += PAGE_SIZE;
}
return 0;
}
static int tgt_mmap(struct file *filp, struct vm_area_struct *vma)
{
unsigned long addr;
int err;
if (vma->vm_pgoff)
return -EINVAL;
if (vma->vm_end - vma->vm_start != TGT_RING_SIZE * 2) {
eprintk("mmap size must be %lu, not %lu \n",
TGT_RING_SIZE * 2, vma->vm_end - vma->vm_start);
return -EINVAL;
}
addr = vma->vm_start;
err = uspace_ring_map(vma, addr, &tx_ring);
if (err)
return err;
err = uspace_ring_map(vma, addr + TGT_RING_SIZE, &rx_ring);
return err;
}
static int tgt_open(struct inode *inode, struct file *file)
{
tx_ring.tr_idx = rx_ring.tr_idx = 0;
cycle_kernel_lock();
return 0;
}
static const struct file_operations tgt_fops = {
.owner = THIS_MODULE,
.open = tgt_open,
.poll = tgt_poll,
.write = tgt_write,
.mmap = tgt_mmap,
};
static struct miscdevice tgt_miscdev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "tgt",
.fops = &tgt_fops,
};
static void tgt_ring_exit(struct tgt_ring *ring)
{
int i;
for (i = 0; i < TGT_RING_PAGES; i++)
free_page(ring->tr_pages[i]);
}
static int tgt_ring_init(struct tgt_ring *ring)
{
int i;
spin_lock_init(&ring->tr_lock);
for (i = 0; i < TGT_RING_PAGES; i++) {
ring->tr_pages[i] = get_zeroed_page(GFP_KERNEL);
if (!ring->tr_pages[i]) {
eprintk("out of memory\n");
return -ENOMEM;
}
}
return 0;
}
void scsi_tgt_if_exit(void)
{
tgt_ring_exit(&tx_ring);
tgt_ring_exit(&rx_ring);
misc_deregister(&tgt_miscdev);
}
int scsi_tgt_if_init(void)
{
int err;
err = tgt_ring_init(&tx_ring);
if (err)
return err;
err = tgt_ring_init(&rx_ring);
if (err)
goto free_tx_ring;
err = misc_register(&tgt_miscdev);
if (err)
goto free_rx_ring;
return 0;
free_rx_ring:
tgt_ring_exit(&rx_ring);
free_tx_ring:
tgt_ring_exit(&tx_ring);
return err;
}

View File

@@ -0,0 +1,108 @@
/*
* SCSI target kernel/user interface
*
* Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org>
* Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#ifndef __SCSI_TARGET_IF_H
#define __SCSI_TARGET_IF_H
/* user -> kernel */
#define TGT_UEVENT_CMD_RSP 0x0001
#define TGT_UEVENT_IT_NEXUS_RSP 0x0002
#define TGT_UEVENT_TSK_MGMT_RSP 0x0003
/* kernel -> user */
#define TGT_KEVENT_CMD_REQ 0x1001
#define TGT_KEVENT_CMD_DONE 0x1002
#define TGT_KEVENT_IT_NEXUS_REQ 0x1003
#define TGT_KEVENT_TSK_MGMT_REQ 0x1004
struct tgt_event_hdr {
uint16_t version;
uint16_t status;
uint16_t type;
uint16_t len;
} __attribute__ ((aligned (sizeof(uint64_t))));
struct tgt_event {
struct tgt_event_hdr hdr;
union {
/* user-> kernel */
struct {
int host_no;
int result;
aligned_u64 itn_id;
aligned_u64 tag;
aligned_u64 uaddr;
aligned_u64 sense_uaddr;
uint32_t len;
uint32_t sense_len;
uint8_t rw;
} cmd_rsp;
struct {
int host_no;
int result;
aligned_u64 itn_id;
aligned_u64 mid;
} tsk_mgmt_rsp;
struct {
__s32 host_no;
__s32 result;
aligned_u64 itn_id;
__u32 function;
} it_nexus_rsp;
/* kernel -> user */
struct {
int host_no;
uint32_t data_len;
aligned_u64 itn_id;
uint8_t scb[16];
uint8_t lun[8];
int attribute;
aligned_u64 tag;
} cmd_req;
struct {
int host_no;
int result;
aligned_u64 itn_id;
aligned_u64 tag;
} cmd_done;
struct {
int host_no;
int function;
aligned_u64 itn_id;
aligned_u64 tag;
uint8_t lun[8];
aligned_u64 mid;
} tsk_mgmt_req;
struct {
__s32 host_no;
__u32 function;
aligned_u64 itn_id;
__u32 max_cmds;
__u8 initiator_id[16];
} it_nexus_req;
} p;
} __attribute__ ((aligned (sizeof(uint64_t))));
#define TGT_RING_SIZE (1UL << 16)
#endif

View File

@@ -0,0 +1,661 @@
/*
* SCSI target lib functions
*
* Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu>
* Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/blkdev.h>
#include <linux/hash.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_tgt.h>
#include "scsi_tgt_priv.h"
static struct workqueue_struct *scsi_tgtd;
static struct kmem_cache *scsi_tgt_cmd_cache;
/*
* TODO: this struct will be killed when the block layer supports large bios
* and James's work struct code is in
*/
struct scsi_tgt_cmd {
/* TODO replace work with James b's code */
struct work_struct work;
/* TODO fix limits of some drivers */
struct bio *bio;
struct list_head hash_list;
struct request *rq;
u64 itn_id;
u64 tag;
};
#define TGT_HASH_ORDER 4
#define cmd_hashfn(tag) hash_long((unsigned long) (tag), TGT_HASH_ORDER)
struct scsi_tgt_queuedata {
struct Scsi_Host *shost;
struct list_head cmd_hash[1 << TGT_HASH_ORDER];
spinlock_t cmd_hash_lock;
};
/*
* Function: scsi_host_get_command()
*
* Purpose: Allocate and setup a scsi command block and blk request
*
* Arguments: shost - scsi host
* data_dir - dma data dir
* gfp_mask- allocator flags
*
* Returns: The allocated scsi command structure.
*
* This should be called by target LLDs to get a command.
*/
struct scsi_cmnd *scsi_host_get_command(struct Scsi_Host *shost,
enum dma_data_direction data_dir,
gfp_t gfp_mask)
{
int write = (data_dir == DMA_TO_DEVICE);
struct request *rq;
struct scsi_cmnd *cmd;
struct scsi_tgt_cmd *tcmd;
/* Bail if we can't get a reference to the device */
if (!get_device(&shost->shost_gendev))
return NULL;
tcmd = kmem_cache_alloc(scsi_tgt_cmd_cache, GFP_ATOMIC);
if (!tcmd)
goto put_dev;
/*
* The blk helpers are used to the READ/WRITE requests
* transfering data from a initiator point of view. Since
* we are in target mode we want the opposite.
*/
rq = blk_get_request(shost->uspace_req_q, !write, gfp_mask);
if (!rq)
goto free_tcmd;
cmd = __scsi_get_command(shost, gfp_mask);
if (!cmd)
goto release_rq;
cmd->sc_data_direction = data_dir;
cmd->jiffies_at_alloc = jiffies;
cmd->request = rq;
cmd->cmnd = rq->cmd;
rq->special = cmd;
rq->cmd_type = REQ_TYPE_SPECIAL;
rq->cmd_flags |= REQ_TYPE_BLOCK_PC;
rq->end_io_data = tcmd;
tcmd->rq = rq;
return cmd;
release_rq:
blk_put_request(rq);
free_tcmd:
kmem_cache_free(scsi_tgt_cmd_cache, tcmd);
put_dev:
put_device(&shost->shost_gendev);
return NULL;
}
EXPORT_SYMBOL_GPL(scsi_host_get_command);
/*
* Function: scsi_host_put_command()
*
* Purpose: Free a scsi command block
*
* Arguments: shost - scsi host
* cmd - command block to free
*
* Returns: Nothing.
*
* Notes: The command must not belong to any lists.
*/
void scsi_host_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
{
struct request_queue *q = shost->uspace_req_q;
struct request *rq = cmd->request;
struct scsi_tgt_cmd *tcmd = rq->end_io_data;
unsigned long flags;
kmem_cache_free(scsi_tgt_cmd_cache, tcmd);
spin_lock_irqsave(q->queue_lock, flags);
__blk_put_request(q, rq);
spin_unlock_irqrestore(q->queue_lock, flags);
__scsi_put_command(shost, cmd, &shost->shost_gendev);
}
EXPORT_SYMBOL_GPL(scsi_host_put_command);
static void cmd_hashlist_del(struct scsi_cmnd *cmd)
{
struct request_queue *q = cmd->request->q;
struct scsi_tgt_queuedata *qdata = q->queuedata;
unsigned long flags;
struct scsi_tgt_cmd *tcmd = cmd->request->end_io_data;
spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
list_del(&tcmd->hash_list);
spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
}
static void scsi_unmap_user_pages(struct scsi_tgt_cmd *tcmd)
{
blk_rq_unmap_user(tcmd->bio);
}
static void scsi_tgt_cmd_destroy(struct work_struct *work)
{
struct scsi_tgt_cmd *tcmd =
container_of(work, struct scsi_tgt_cmd, work);
struct scsi_cmnd *cmd = tcmd->rq->special;
dprintk("cmd %p %d %u\n", cmd, cmd->sc_data_direction,
rq_data_dir(cmd->request));
scsi_unmap_user_pages(tcmd);
scsi_host_put_command(scsi_tgt_cmd_to_host(cmd), cmd);
}
static void init_scsi_tgt_cmd(struct request *rq, struct scsi_tgt_cmd *tcmd,
u64 itn_id, u64 tag)
{
struct scsi_tgt_queuedata *qdata = rq->q->queuedata;
unsigned long flags;
struct list_head *head;
tcmd->itn_id = itn_id;
tcmd->tag = tag;
tcmd->bio = NULL;
INIT_WORK(&tcmd->work, scsi_tgt_cmd_destroy);
spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
head = &qdata->cmd_hash[cmd_hashfn(tag)];
list_add(&tcmd->hash_list, head);
spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
}
/*
* scsi_tgt_alloc_queue - setup queue used for message passing
* shost: scsi host
*
* This should be called by the LLD after host allocation.
* And will be released when the host is released.
*/
int scsi_tgt_alloc_queue(struct Scsi_Host *shost)
{
struct scsi_tgt_queuedata *queuedata;
struct request_queue *q;
int err, i;
/*
* Do we need to send a netlink event or should uspace
* just respond to the hotplug event?
*/
q = __scsi_alloc_queue(shost, NULL);
if (!q)
return -ENOMEM;
queuedata = kzalloc(sizeof(*queuedata), GFP_KERNEL);
if (!queuedata) {
err = -ENOMEM;
goto cleanup_queue;
}
queuedata->shost = shost;
q->queuedata = queuedata;
/*
* this is a silly hack. We should probably just queue as many
* command as is recvd to userspace. uspace can then make
* sure we do not overload the HBA
*/
q->nr_requests = shost->can_queue;
/*
* We currently only support software LLDs so this does
* not matter for now. Do we need this for the cards we support?
* If so we should make it a host template value.
*/
blk_queue_dma_alignment(q, 0);
shost->uspace_req_q = q;
for (i = 0; i < ARRAY_SIZE(queuedata->cmd_hash); i++)
INIT_LIST_HEAD(&queuedata->cmd_hash[i]);
spin_lock_init(&queuedata->cmd_hash_lock);
return 0;
cleanup_queue:
blk_cleanup_queue(q);
return err;
}
EXPORT_SYMBOL_GPL(scsi_tgt_alloc_queue);
void scsi_tgt_free_queue(struct Scsi_Host *shost)
{
int i;
unsigned long flags;
struct request_queue *q = shost->uspace_req_q;
struct scsi_cmnd *cmd;
struct scsi_tgt_queuedata *qdata = q->queuedata;
struct scsi_tgt_cmd *tcmd, *n;
LIST_HEAD(cmds);
spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
for (i = 0; i < ARRAY_SIZE(qdata->cmd_hash); i++) {
list_for_each_entry_safe(tcmd, n, &qdata->cmd_hash[i],
hash_list) {
list_del(&tcmd->hash_list);
list_add(&tcmd->hash_list, &cmds);
}
}
spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
while (!list_empty(&cmds)) {
tcmd = list_entry(cmds.next, struct scsi_tgt_cmd, hash_list);
list_del(&tcmd->hash_list);
cmd = tcmd->rq->special;
shost->hostt->eh_abort_handler(cmd);
scsi_tgt_cmd_destroy(&tcmd->work);
}
}
EXPORT_SYMBOL_GPL(scsi_tgt_free_queue);
struct Scsi_Host *scsi_tgt_cmd_to_host(struct scsi_cmnd *cmd)
{
struct scsi_tgt_queuedata *queue = cmd->request->q->queuedata;
return queue->shost;
}
EXPORT_SYMBOL_GPL(scsi_tgt_cmd_to_host);
/*
* scsi_tgt_queue_command - queue command for userspace processing
* @cmd: scsi command
* @scsilun: scsi lun
* @tag: unique value to identify this command for tmf
*/
int scsi_tgt_queue_command(struct scsi_cmnd *cmd, u64 itn_id,
struct scsi_lun *scsilun, u64 tag)
{
struct scsi_tgt_cmd *tcmd = cmd->request->end_io_data;
int err;
init_scsi_tgt_cmd(cmd->request, tcmd, itn_id, tag);
err = scsi_tgt_uspace_send_cmd(cmd, itn_id, scsilun, tag);
if (err)
cmd_hashlist_del(cmd);
return err;
}
EXPORT_SYMBOL_GPL(scsi_tgt_queue_command);
/*
* This is run from a interrupt handler normally and the unmap
* needs process context so we must queue
*/
static void scsi_tgt_cmd_done(struct scsi_cmnd *cmd)
{
struct scsi_tgt_cmd *tcmd = cmd->request->end_io_data;
dprintk("cmd %p %u\n", cmd, rq_data_dir(cmd->request));
scsi_tgt_uspace_send_status(cmd, tcmd->itn_id, tcmd->tag);
scsi_release_buffers(cmd);
queue_work(scsi_tgtd, &tcmd->work);
}
static int scsi_tgt_transfer_response(struct scsi_cmnd *cmd)
{
struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd);
int err;
dprintk("cmd %p %u\n", cmd, rq_data_dir(cmd->request));
err = shost->hostt->transfer_response(cmd, scsi_tgt_cmd_done);
switch (err) {
case SCSI_MLQUEUE_HOST_BUSY:
case SCSI_MLQUEUE_DEVICE_BUSY:
return -EAGAIN;
}
return 0;
}
/* TODO: test this crap and replace bio_map_user with new interface maybe */
static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd,
unsigned long uaddr, unsigned int len, int rw)
{
struct request_queue *q = cmd->request->q;
struct request *rq = cmd->request;
int err;
dprintk("%lx %u\n", uaddr, len);
err = blk_rq_map_user(q, rq, NULL, (void *)uaddr, len, GFP_KERNEL);
if (err) {
/*
* TODO: need to fixup sg_tablesize, max_segment_size,
* max_sectors, etc for modern HW and software drivers
* where this value is bogus.
*
* TODO2: we can alloc a reserve buffer of max size
* we can handle and do the slow copy path for really large
* IO.
*/
eprintk("Could not handle request of size %u.\n", len);
return err;
}
tcmd->bio = rq->bio;
err = scsi_init_io(cmd, GFP_KERNEL);
if (err) {
scsi_release_buffers(cmd);
goto unmap_rq;
}
/*
* we use REQ_TYPE_BLOCK_PC so scsi_init_io doesn't set the
* length for us.
*/
cmd->sdb.length = blk_rq_bytes(rq);
return 0;
unmap_rq:
scsi_unmap_user_pages(tcmd);
return err;
}
static int scsi_tgt_copy_sense(struct scsi_cmnd *cmd, unsigned long uaddr,
unsigned len)
{
char __user *p = (char __user *) uaddr;
if (copy_from_user(cmd->sense_buffer, p,
min_t(unsigned, SCSI_SENSE_BUFFERSIZE, len))) {
printk(KERN_ERR "Could not copy the sense buffer\n");
return -EIO;
}
return 0;
}
static int scsi_tgt_abort_cmd(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
{
struct scsi_tgt_cmd *tcmd;
int err;
err = shost->hostt->eh_abort_handler(cmd);
if (err)
eprintk("fail to abort %p\n", cmd);
tcmd = cmd->request->end_io_data;
scsi_tgt_cmd_destroy(&tcmd->work);
return err;
}
static struct request *tgt_cmd_hash_lookup(struct request_queue *q, u64 tag)
{
struct scsi_tgt_queuedata *qdata = q->queuedata;
struct request *rq = NULL;
struct list_head *head;
struct scsi_tgt_cmd *tcmd;
unsigned long flags;
head = &qdata->cmd_hash[cmd_hashfn(tag)];
spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
list_for_each_entry(tcmd, head, hash_list) {
if (tcmd->tag == tag) {
rq = tcmd->rq;
list_del(&tcmd->hash_list);
break;
}
}
spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
return rq;
}
int scsi_tgt_kspace_exec(int host_no, u64 itn_id, int result, u64 tag,
unsigned long uaddr, u32 len, unsigned long sense_uaddr,
u32 sense_len, u8 rw)
{
struct Scsi_Host *shost;
struct scsi_cmnd *cmd;
struct request *rq;
struct scsi_tgt_cmd *tcmd;
int err = 0;
dprintk("%d %llu %d %u %lx %u\n", host_no, (unsigned long long) tag,
result, len, uaddr, rw);
/* TODO: replace with a O(1) alg */
shost = scsi_host_lookup(host_no);
if (!shost) {
printk(KERN_ERR "Could not find host no %d\n", host_no);
return -EINVAL;
}
if (!shost->uspace_req_q) {
printk(KERN_ERR "Not target scsi host %d\n", host_no);
goto done;
}
rq = tgt_cmd_hash_lookup(shost->uspace_req_q, tag);
if (!rq) {
printk(KERN_ERR "Could not find tag %llu\n",
(unsigned long long) tag);
err = -EINVAL;
goto done;
}
cmd = rq->special;
dprintk("cmd %p scb %x result %d len %d bufflen %u %u %x\n",
cmd, cmd->cmnd[0], result, len, scsi_bufflen(cmd),
rq_data_dir(rq), cmd->cmnd[0]);
if (result == TASK_ABORTED) {
scsi_tgt_abort_cmd(shost, cmd);
goto done;
}
/*
* store the userspace values here, the working values are
* in the request_* values
*/
tcmd = cmd->request->end_io_data;
cmd->result = result;
if (cmd->result == SAM_STAT_CHECK_CONDITION)
scsi_tgt_copy_sense(cmd, sense_uaddr, sense_len);
if (len) {
err = scsi_map_user_pages(rq->end_io_data, cmd, uaddr, len, rw);
if (err) {
/*
* user-space daemon bugs or OOM
* TODO: we can do better for OOM.
*/
struct scsi_tgt_queuedata *qdata;
struct list_head *head;
unsigned long flags;
eprintk("cmd %p ret %d uaddr %lx len %d rw %d\n",
cmd, err, uaddr, len, rw);
qdata = shost->uspace_req_q->queuedata;
head = &qdata->cmd_hash[cmd_hashfn(tcmd->tag)];
spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
list_add(&tcmd->hash_list, head);
spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
goto done;
}
}
err = scsi_tgt_transfer_response(cmd);
done:
scsi_host_put(shost);
return err;
}
int scsi_tgt_tsk_mgmt_request(struct Scsi_Host *shost, u64 itn_id,
int function, u64 tag, struct scsi_lun *scsilun,
void *data)
{
int err;
/* TODO: need to retry if this fails. */
err = scsi_tgt_uspace_send_tsk_mgmt(shost->host_no, itn_id,
function, tag, scsilun, data);
if (err < 0)
eprintk("The task management request lost!\n");
return err;
}
EXPORT_SYMBOL_GPL(scsi_tgt_tsk_mgmt_request);
int scsi_tgt_kspace_tsk_mgmt(int host_no, u64 itn_id, u64 mid, int result)
{
struct Scsi_Host *shost;
int err = -EINVAL;
dprintk("%d %d %llx\n", host_no, result, (unsigned long long) mid);
shost = scsi_host_lookup(host_no);
if (!shost) {
printk(KERN_ERR "Could not find host no %d\n", host_no);
return err;
}
if (!shost->uspace_req_q) {
printk(KERN_ERR "Not target scsi host %d\n", host_no);
goto done;
}
err = shost->transportt->tsk_mgmt_response(shost, itn_id, mid, result);
done:
scsi_host_put(shost);
return err;
}
int scsi_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
char *initiator)
{
int err;
/* TODO: need to retry if this fails. */
err = scsi_tgt_uspace_send_it_nexus_request(shost->host_no, itn_id, 0,
initiator);
if (err < 0)
eprintk("The i_t_neuxs request lost, %d %llx!\n",
shost->host_no, (unsigned long long)itn_id);
return err;
}
EXPORT_SYMBOL_GPL(scsi_tgt_it_nexus_create);
int scsi_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
{
int err;
/* TODO: need to retry if this fails. */
err = scsi_tgt_uspace_send_it_nexus_request(shost->host_no,
itn_id, 1, NULL);
if (err < 0)
eprintk("The i_t_neuxs request lost, %d %llx!\n",
shost->host_no, (unsigned long long)itn_id);
return err;
}
EXPORT_SYMBOL_GPL(scsi_tgt_it_nexus_destroy);
int scsi_tgt_kspace_it_nexus_rsp(int host_no, u64 itn_id, int result)
{
struct Scsi_Host *shost;
int err = -EINVAL;
dprintk("%d %d%llx\n", host_no, result, (unsigned long long)itn_id);
shost = scsi_host_lookup(host_no);
if (!shost) {
printk(KERN_ERR "Could not find host no %d\n", host_no);
return err;
}
if (!shost->uspace_req_q) {
printk(KERN_ERR "Not target scsi host %d\n", host_no);
goto done;
}
err = shost->transportt->it_nexus_response(shost, itn_id, result);
done:
scsi_host_put(shost);
return err;
}
static int __init scsi_tgt_init(void)
{
int err;
scsi_tgt_cmd_cache = KMEM_CACHE(scsi_tgt_cmd, 0);
if (!scsi_tgt_cmd_cache)
return -ENOMEM;
scsi_tgtd = create_workqueue("scsi_tgtd");
if (!scsi_tgtd) {
err = -ENOMEM;
goto free_kmemcache;
}
err = scsi_tgt_if_init();
if (err)
goto destroy_wq;
return 0;
destroy_wq:
destroy_workqueue(scsi_tgtd);
free_kmemcache:
kmem_cache_destroy(scsi_tgt_cmd_cache);
return err;
}
static void __exit scsi_tgt_exit(void)
{
destroy_workqueue(scsi_tgtd);
scsi_tgt_if_exit();
kmem_cache_destroy(scsi_tgt_cmd_cache);
}
module_init(scsi_tgt_init);
module_exit(scsi_tgt_exit);
MODULE_DESCRIPTION("SCSI target core");
MODULE_LICENSE("GPL");

View File

@@ -0,0 +1,32 @@
struct scsi_cmnd;
struct scsi_lun;
struct Scsi_Host;
struct task_struct;
/* tmp - will replace with SCSI logging stuff */
#define eprintk(fmt, args...) \
do { \
printk("%s(%d) " fmt, __func__, __LINE__, ##args); \
} while (0)
#define dprintk(fmt, args...)
/* #define dprintk eprintk */
extern void scsi_tgt_if_exit(void);
extern int scsi_tgt_if_init(void);
extern int scsi_tgt_uspace_send_cmd(struct scsi_cmnd *cmd, u64 it_nexus_id,
struct scsi_lun *lun, u64 tag);
extern int scsi_tgt_uspace_send_status(struct scsi_cmnd *cmd, u64 it_nexus_id,
u64 tag);
extern int scsi_tgt_kspace_exec(int host_no, u64 it_nexus_id, int result, u64 tag,
unsigned long uaddr, u32 len,
unsigned long sense_uaddr, u32 sense_len, u8 rw);
extern int scsi_tgt_uspace_send_tsk_mgmt(int host_no, u64 it_nexus_id,
int function, u64 tag,
struct scsi_lun *scsilun, void *data);
extern int scsi_tgt_kspace_tsk_mgmt(int host_no, u64 it_nexus_id,
u64 mid, int result);
extern int scsi_tgt_uspace_send_it_nexus_request(int host_no, u64 it_nexus_id,
int function, char *initiator);
extern int scsi_tgt_kspace_it_nexus_rsp(int host_no, u64 it_nexus_id, int result);

View File

@@ -0,0 +1,26 @@
#include <scsi/scsi_tgt.h>
#ifdef CONFIG_SCSI_FC_TGT_ATTRS
static inline int fc_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
char *initiator)
{
return scsi_tgt_it_nexus_create(shost, itn_id, initiator);
}
static inline int fc_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
{
return scsi_tgt_it_nexus_destroy(shost, itn_id);
}
#else
static inline int fc_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
char *initiator)
{
return 0;
}
static inline int fc_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
{
return 0;
}
#endif

View File

@@ -0,0 +1,25 @@
#include <scsi/scsi_tgt.h>
#ifdef CONFIG_SCSI_SRP_TGT_ATTRS
static inline int srp_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
char *initiator)
{
return scsi_tgt_it_nexus_create(shost, itn_id, initiator);
}
static inline int srp_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
{
return scsi_tgt_it_nexus_destroy(shost, itn_id);
}
#else
static inline int srp_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
char *initiator)
{
return 0;
}
static inline int srp_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
{
return 0;
}
#endif

857
ibmvstgt/src/scsi_host.h Normal file
View File

@@ -0,0 +1,857 @@
#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 <scsi/scsi.h>
struct request_queue;
struct block_device;
struct completion;
struct module;
struct scsi_cmnd;
struct scsi_device;
struct scsi_target;
struct Scsi_Host;
struct scsi_host_cmd_pool;
struct scsi_transport_template;
struct blk_queue_tags;
/*
* The various choices mean:
* NONE: Self evident. Host adapter is not capable of scatter-gather.
* ALL: Means that the host adapter module can do scatter-gather,
* and that there is no limit to the size of the table to which
* we scatter/gather data. The value we set here is the maximum
* single element sglist. To use chained sglists, the adapter
* has to set a value beyond ALL (and correctly use the chain
* handling API.
* Anything else: Indicates the maximum number of chains that can be
* used in one scatter-gather request.
*/
#define SG_NONE 0
#define SG_ALL SCSI_MAX_SG_SEGMENTS
#define MODE_UNKNOWN 0x00
#define MODE_INITIATOR 0x01
#define MODE_TARGET 0x02
#define DISABLE_CLUSTERING 0
#define ENABLE_CLUSTERING 1
enum {
SCSI_QDEPTH_DEFAULT, /* default requested change, e.g. from sysfs */
SCSI_QDEPTH_QFULL, /* scsi-ml requested due to queue full */
SCSI_QDEPTH_RAMP_UP, /* scsi-ml requested due to threshhold event */
};
struct scsi_host_template {
struct module *module;
const char *name;
/*
* Used to initialize old-style drivers. For new-style drivers
* just perform all work in your module initialization function.
*
* Status: OBSOLETE
*/
int (* detect)(struct scsi_host_template *);
/*
* Used as unload callback for hosts with old-style drivers.
*
* Status: OBSOLETE
*/
int (* release)(struct Scsi_Host *);
/*
* 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, 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, int cmd, void __user *arg);
#endif
/*
* 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 HBA has accepted the
* command. 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_cmnd *,
void (*done)(struct scsi_cmnd *));
/*
* 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_adjust_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, int);
/*
* Fill in this function to allow the changing of tag types
* (this also allows the enabling/disabling of tag command
* queueing). An error should only be returned if something
* went wrong in the driver while trying to set the tag type.
* If the driver doesn't support the requested tag type, then
* it should set the closest type it does support without
* returning an error. Returns the actual tag type set.
*
* Status: OPTIONAL
*/
int (* change_queue_type)(struct scsi_device *, int);
/*
* 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 (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, 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:
* EH_HANDLED: I fixed the error, please complete the command
* EH_RESET_TIMER: I need more time, reset the timer and
* begin counting again
* EH_NOT_HANDLED Begin normal error recovery
*
* Status: OPTIONAL
*/
enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
/*
* Name of proc directory
*/
const char *proc_name;
/*
* Used to store the procfs directory if a driver implements the
* proc_info method.
*/
struct proc_dir_entry *proc_dir;
/*
* 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 given host adapter 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;
/*
* Set this if the host adapter has limitations beside segment count.
*/
unsigned short max_sectors;
/*
* DMA scatter gather segment boundary limit. A segment crossing this
* boundary will be split in two.
*/
unsigned long dma_boundary;
/*
* 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;
/*
* present contains counter indicating how many boards of this
* type were found when we did the scan.
*/
unsigned char present;
/*
* This specifies the mode that a LLD supports.
*/
unsigned supported_mode:2;
/*
* True if this host adapter uses unchecked DMA onto an ISA bus.
*/
unsigned unchecked_isa_dma:1;
/*
* True if this host adapter can make good use of clustering.
* I originally thought that if the tablesize was large that it
* was a waste of CPU cycles to prepare a cluster list, but
* it works out that the Buslogic is faster if you use a smaller
* number of segments (i.e. use clustering). I guess it is
* inefficient.
*/
unsigned use_clustering:1;
/*
* 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 we are using ordered write support.
*/
unsigned ordered_tag: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 sysfs class properties for this host, NULL terminated.
*/
struct device_attribute **shost_attrs;
/*
* Pointer to the SCSI device properties for this host, NULL terminated.
*/
struct device_attribute **sdev_attrs;
/*
* List of hosts per template.
*
* This is only for use by scsi_module.c for legacy templates.
* For these access to it is synchronized implicitly by
* module_init/module_exit.
*/
struct list_head legacy_hosts;
/*
* 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;
};
/*
* 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 beeing 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 scsi_host_cmd_pool *cmd_pool;
spinlock_t free_list_lock;
struct list_head free_list; /* backup store of cmd structs */
struct list_head starved_list;
spinlock_t default_lock;
spinlock_t *host_lock;
struct mutex scan_mutex;/* serialize scanning activity */
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;
struct scsi_host_template *hostt;
struct scsi_transport_template *transportt;
/*
* Area to keep a shared tag map (if needed, will be
* NULL if not).
*/
struct blk_queue_tag *bqt;
/*
* The following two fields are protected with host_lock;
* however, eh routines can safely access during eh processing
* without acquiring the lock.
*/
unsigned int host_busy; /* commands actually active on low-level */
unsigned int host_failed; /* commands that failed. */
unsigned int host_eh_scheduled; /* EH scheduled without command */
unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
int resetting; /* if set, it means that last_reset is a valid value */
unsigned long last_reset;
/*
* These three parameters can be used to allow for wide scsi,
* and for host adapters that support multiple busses
* The first two should be set to 1 more than the actual max id
* or lun (i.e. 8 for normal systems).
*/
unsigned int max_id;
unsigned int max_lun;
unsigned int max_channel;
/*
* 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 max_sectors;
unsigned long dma_boundary;
/*
* Used to assign serial numbers to the cmds.
* Protected by the host lock.
*/
unsigned long cmd_serial_number;
unsigned active_mode:2;
unsigned unchecked_isa_dma:1;
unsigned use_clustering:1;
unsigned use_blk_tcq:1;
/*
* 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;
/*
* Ordered write support
*/
unsigned ordered_tag:1;
/* Task mgmt function in progress */
unsigned tmf_in_progress:1;
/* Asynchronous scan in progress */
unsigned async_scan:1;
/*
* Optional work queue to be utilized by the transport
*/
char work_q_name[20];
struct workqueue_struct *work_q;
/*
* Host has rejected a command because it was busy.
*/
unsigned int host_blocked;
/*
* Value host_blocked counts down from
*/
unsigned int max_host_blocked;
/* Protection Information */
unsigned int prot_capabilities;
unsigned char prot_guard_type;
/*
* q used for scsi_tgt msgs, async events or any other requests that
* need to be processed in userspace
*/
struct request_queue *uspace_req_q;
/* 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;
/*
* List of hosts per template.
*
* This is only for use by scsi_module.c for legacy templates.
* For these access to it is synchronized implicitly by
* module_init/module_exit.
*/
struct list_head sht_legacy_list;
/*
* 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[0] /* 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(struct scsi_host_template *, int);
extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
struct device *,
struct device *);
extern void scsi_scan_host(struct Scsi_Host *);
extern void scsi_rescan_device(struct device *);
extern void scsi_remove_host(struct Scsi_Host *);
extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
extern void scsi_host_put(struct Scsi_Host *t);
extern struct Scsi_Host *scsi_host_lookup(unsigned short);
extern const char *scsi_host_state_name(enum scsi_host_state);
extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *);
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;
}
extern void scsi_unblock_requests(struct Scsi_Host *);
extern void scsi_block_requests(struct Scsi_Host *);
struct class_container;
extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
void (*) (struct request_queue *));
/*
* These two functions are used to allocate and free a pseudo device
* which will connect to the host adapter itself rather than any
* physical device. You must deallocate when you are done with the
* thing. This physical pseudo-device isn't real and won't be available
* from any high-level drivers.
*/
extern void scsi_free_host_dev(struct scsi_device *);
extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
/*
* 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 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 };
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 };
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;
}
/* legacy interfaces */
extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
extern void scsi_unregister(struct Scsi_Host *);
extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
#endif /* _SCSI_SCSI_HOST_H */

3
ibmvstgt/src/scsi_tgt.h Normal file
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@@ -0,0 +1,3 @@
/*
* SCSI target definitions
*/

289
ibmvstgt/src/scsi_tgt_if.c Normal file
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@@ -0,0 +1,289 @@
/*
* SCSI target kernel/user interface functions
*
* Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org>
* Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/miscdevice.h>
#include <linux/gfp.h>
#include <linux/file.h>
#include <linux/smp_lock.h>
#include <net/tcp.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tgt.h>
#include <scsi/scsi_tgt_if.h>
#include <asm/cacheflush.h>
#include "scsi_tgt_priv.h"
#if TGT_RING_SIZE < PAGE_SIZE
# define TGT_RING_SIZE PAGE_SIZE
#endif
#define TGT_RING_PAGES (TGT_RING_SIZE >> PAGE_SHIFT)
#define TGT_EVENT_PER_PAGE (PAGE_SIZE / sizeof(struct tgt_event))
#define TGT_MAX_EVENTS (TGT_EVENT_PER_PAGE * TGT_RING_PAGES)
struct tgt_ring {
u32 tr_idx;
unsigned long tr_pages[TGT_RING_PAGES];
spinlock_t tr_lock;
};
/* tx_ring : kernel->user, rx_ring : user->kernel */
static struct tgt_ring tx_ring, rx_ring;
static DECLARE_WAIT_QUEUE_HEAD(tgt_poll_wait);
static inline void tgt_ring_idx_inc(struct tgt_ring *ring)
{
if (ring->tr_idx == TGT_MAX_EVENTS - 1)
ring->tr_idx = 0;
else
ring->tr_idx++;
}
static struct tgt_event *tgt_head_event(struct tgt_ring *ring, u32 idx)
{
u32 pidx, off;
pidx = idx / TGT_EVENT_PER_PAGE;
off = idx % TGT_EVENT_PER_PAGE;
return (struct tgt_event *)
(ring->tr_pages[pidx] + sizeof(struct tgt_event) * off);
}
static int tgt_uspace_send_event(u32 type, struct tgt_event *p)
{
struct tgt_event *ev;
struct tgt_ring *ring = &tx_ring;
unsigned long flags;
int err = 0;
spin_lock_irqsave(&ring->tr_lock, flags);
ev = tgt_head_event(ring, ring->tr_idx);
if (!ev->hdr.status)
tgt_ring_idx_inc(ring);
else
err = -BUSY;
spin_unlock_irqrestore(&ring->tr_lock, flags);
if (err)
return err;
memcpy(ev, p, sizeof(*ev));
ev->hdr.type = type;
mb();
ev->hdr.status = 1;
flush_dcache_page(virt_to_page(ev));
wake_up_interruptible(&tgt_poll_wait);
return 0;
}
static int event_recv_msg(struct tgt_event *ev)
{
int err = 0;
switch (ev->hdr.type) {
case TGT_UEVENT_CMD_RSP:
err = -EINVAL;
break;
case TGT_UEVENT_TSK_MGMT_RSP:
err = -EINVAL;
break;
case TGT_UEVENT_IT_NEXUS_RSP:
err = -EINVAL;
break;
default:
eprintk("unknown type %d\n", ev->hdr.type);
err = -EINVAL;
}
return err;
}
static ssize_t tgt_write(struct file *file, const char __user * buffer,
size_t count, loff_t * ppos)
{
struct tgt_event *ev;
struct tgt_ring *ring = &rx_ring;
while (1) {
ev = tgt_head_event(ring, ring->tr_idx);
/* do we need this? */
flush_dcache_page(virt_to_page(ev));
if (!ev->hdr.status)
break;
tgt_ring_idx_inc(ring);
event_recv_msg(ev);
ev->hdr.status = 0;
};
return count;
}
static unsigned int tgt_poll(struct file * file, struct poll_table_struct *wait)
{
struct tgt_event *ev;
struct tgt_ring *ring = &tx_ring;
unsigned long flags;
unsigned int mask = 0;
u32 idx;
poll_wait(file, &tgt_poll_wait, wait);
spin_lock_irqsave(&ring->tr_lock, flags);
idx = ring->tr_idx ? ring->tr_idx - 1 : TGT_MAX_EVENTS - 1;
ev = tgt_head_event(ring, idx);
if (ev->hdr.status)
mask |= POLLIN | POLLRDNORM;
spin_unlock_irqrestore(&ring->tr_lock, flags);
return mask;
}
static int uspace_ring_map(struct vm_area_struct *vma, unsigned long addr,
struct tgt_ring *ring)
{
int i, err;
for (i = 0; i < TGT_RING_PAGES; i++) {
struct page *page = virt_to_page(ring->tr_pages[i]);
err = vm_insert_page(vma, addr, page);
if (err)
return err;
addr += PAGE_SIZE;
}
return 0;
}
static int tgt_mmap(struct file *filp, struct vm_area_struct *vma)
{
unsigned long addr;
int err;
if (vma->vm_pgoff)
return -EINVAL;
if (vma->vm_end - vma->vm_start != TGT_RING_SIZE * 2) {
eprintk("mmap size must be %lu, not %lu \n",
TGT_RING_SIZE * 2, vma->vm_end - vma->vm_start);
return -EINVAL;
}
addr = vma->vm_start;
err = uspace_ring_map(vma, addr, &tx_ring);
if (err)
return err;
err = uspace_ring_map(vma, addr + TGT_RING_SIZE, &rx_ring);
return err;
}
static int tgt_open(struct inode *inode, struct file *file)
{
tx_ring.tr_idx = rx_ring.tr_idx = 0;
cycle_kernel_lock();
return 0;
}
static const struct file_operations tgt_fops = {
.owner = THIS_MODULE,
.open = tgt_open,
.poll = tgt_poll,
.write = tgt_write,
.mmap = tgt_mmap,
};
static struct miscdevice tgt_miscdev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "tgt",
.fops = &tgt_fops,
};
static void tgt_ring_exit(struct tgt_ring *ring)
{
int i;
for (i = 0; i < TGT_RING_PAGES; i++)
free_page(ring->tr_pages[i]);
}
static int tgt_ring_init(struct tgt_ring *ring)
{
int i;
spin_lock_init(&ring->tr_lock);
for (i = 0; i < TGT_RING_PAGES; i++) {
ring->tr_pages[i] = get_zeroed_page(GFP_KERNEL);
if (!ring->tr_pages[i]) {
eprintk("out of memory\n");
return -ENOMEM;
}
}
return 0;
}
void scsi_tgt_if_exit(void)
{
tgt_ring_exit(&tx_ring);
tgt_ring_exit(&rx_ring);
misc_deregister(&tgt_miscdev);
}
int scsi_tgt_if_init(void)
{
int err;
err = tgt_ring_init(&tx_ring);
if (err)
return err;
err = tgt_ring_init(&rx_ring);
if (err)
goto free_tx_ring;
err = misc_register(&tgt_miscdev);
if (err)
goto free_rx_ring;
return 0;
free_rx_ring:
tgt_ring_exit(&rx_ring);
free_tx_ring:
tgt_ring_exit(&tx_ring);
return err;
}

108
ibmvstgt/src/scsi_tgt_if.h Normal file
View File

@@ -0,0 +1,108 @@
/*
* SCSI target kernel/user interface
*
* Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org>
* Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#ifndef __SCSI_TARGET_IF_H
#define __SCSI_TARGET_IF_H
/* user -> kernel */
#define TGT_UEVENT_CMD_RSP 0x0001
#define TGT_UEVENT_IT_NEXUS_RSP 0x0002
#define TGT_UEVENT_TSK_MGMT_RSP 0x0003
/* kernel -> user */
#define TGT_KEVENT_CMD_REQ 0x1001
#define TGT_KEVENT_CMD_DONE 0x1002
#define TGT_KEVENT_IT_NEXUS_REQ 0x1003
#define TGT_KEVENT_TSK_MGMT_REQ 0x1004
struct tgt_event_hdr {
uint16_t version;
uint16_t status;
uint16_t type;
uint16_t len;
} __attribute__ ((aligned (sizeof(uint64_t))));
struct tgt_event {
struct tgt_event_hdr hdr;
union {
/* user-> kernel */
struct {
int host_no;
int result;
aligned_u64 itn_id;
aligned_u64 tag;
aligned_u64 uaddr;
aligned_u64 sense_uaddr;
uint32_t len;
uint32_t sense_len;
uint8_t rw;
} cmd_rsp;
struct {
int host_no;
int result;
aligned_u64 itn_id;
aligned_u64 mid;
} tsk_mgmt_rsp;
struct {
__s32 host_no;
__s32 result;
aligned_u64 itn_id;
__u32 function;
} it_nexus_rsp;
/* kernel -> user */
struct {
int host_no;
uint32_t data_len;
aligned_u64 itn_id;
uint8_t scb[16];
uint8_t lun[8];
int attribute;
aligned_u64 tag;
} cmd_req;
struct {
int host_no;
int result;
aligned_u64 itn_id;
aligned_u64 tag;
} cmd_done;
struct {
int host_no;
int function;
aligned_u64 itn_id;
aligned_u64 tag;
uint8_t lun[8];
aligned_u64 mid;
} tsk_mgmt_req;
struct {
__s32 host_no;
__u32 function;
aligned_u64 itn_id;
__u32 max_cmds;
__u8 initiator_id[16];
} it_nexus_req;
} p;
} __attribute__ ((aligned (sizeof(uint64_t))));
#define TGT_RING_SIZE (1UL << 16)
#endif

102
ibmvstgt/src/scsi_tgt_lib.c Normal file
View File

@@ -0,0 +1,102 @@
/*
* SCSI target lib functions
*
* Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu>
* Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/blkdev.h>
#include <linux/hash.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_tgt.h>
#include "scsi_tgt_priv.h"
static struct workqueue_struct *scsi_tgtd;
static struct kmem_cache *scsi_tgt_cmd_cache;
/*
* TODO: this struct will be killed when the block layer supports large bios
* and James's work struct code is in
*/
struct scsi_tgt_cmd {
/* TODO replace work with James b's code */
struct work_struct work;
/* TODO fix limits of some drivers */
struct bio *bio;
struct list_head hash_list;
struct request *rq;
u64 itn_id;
u64 tag;
};
#define TGT_HASH_ORDER 4
#define cmd_hashfn(tag) hash_long((unsigned long) (tag), TGT_HASH_ORDER)
struct scsi_tgt_queuedata {
struct Scsi_Host *shost;
struct list_head cmd_hash[1 << TGT_HASH_ORDER];
spinlock_t cmd_hash_lock;
};
static int __init scsi_tgt_init(void)
{
int err;
scsi_tgt_cmd_cache = KMEM_CACHE(scsi_tgt_cmd, 0);
if (!scsi_tgt_cmd_cache)
return -ENOMEM;
scsi_tgtd = create_workqueue("scsi_tgtd");
if (!scsi_tgtd) {
err = -ENOMEM;
goto free_kmemcache;
}
err = scsi_tgt_if_init();
if (err)
goto destroy_wq;
return 0;
destroy_wq:
destroy_workqueue(scsi_tgtd);
free_kmemcache:
kmem_cache_destroy(scsi_tgt_cmd_cache);
return err;
}
static void __exit scsi_tgt_exit(void)
{
destroy_workqueue(scsi_tgtd);
scsi_tgt_if_exit();
kmem_cache_destroy(scsi_tgt_cmd_cache);
}
module_init(scsi_tgt_init);
module_exit(scsi_tgt_exit);
MODULE_DESCRIPTION("SCSI target core");
MODULE_LICENSE("GPL");

View File

@@ -0,0 +1,11 @@
/* tmp - will replace with SCSI logging stuff */
#define eprintk(fmt, args...) \
do { \
printk("%s(%d) " fmt, __func__, __LINE__, ##args); \
} while (0)
#define dprintk(fmt, args...)
/* #define dprintk eprintk */
extern void scsi_tgt_if_exit(void);
extern int scsi_tgt_if_init(void);

View File

@@ -0,0 +1,10 @@
static inline int fc_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
char *initiator)
{
return 0;
}
static inline int fc_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
{
return 0;
}

View File

@@ -0,0 +1,9 @@
static inline int srp_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
char *initiator)
{
return 0;
}
static inline int srp_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
{
return 0;
}