xref: /illumos-gate/usr/src/man/man9f/scsi_hba_tgtmap_create.9f (revision 3385b4726f1b09aa9511340017fb23c7cde6aadd)
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14.Dd Apr 18, 2017
15.Dt SCSI_HBA_TGTMAP_CREATE 9F
16.Os
17.Sh NAME
18.Nm scsi_hba_tgtmap_create ,
19.Nm scsi_hba_tgtmap_destroy ,
20.Nm scsi_hba_tgtmap_set_begin ,
21.Nm scsi_hba_tgtmap_set_add ,
22.Nm scsi_hba_tgtmap_set_end ,
23.Nm scsi_hba_tgtmap_set_flush ,
24.Nm scsi_hba_tgtmap_tgt_add ,
25.Nm scsi_hba_tgtmap_tgt_remove
26.Nd SCSI target map functions
27.Sh SYNOPSIS
28.In sys/scsi/scsi.h
29.Ft int
30.Fo scsi_hba_tgtmap_create
31.Fa "dev_info_t *dip"
32.Fa "scsi_tgtmap_mode_t mode"
33.Fa "int csync_usec"
34.Fa "int settle_usec"
35.Fa "void *tgtmap_priv"
36.Fa "scsi_tgt_activate_cb_t activate_cb"
37.Fa "scsi_tgt_deactivate_cb_t deactivate_cb"
38.Fa "scsi_hba_tgtmap_t *tgtmapout"
39.Fc
40.Ft void
41.Fo scsi_hba_tgtmap_destroy
42.Fa "scsi_hba_tgtmap_t *tgtmap"
43.Fc
44.Ft void
45.Fo (*scsi_tgt_activate_cb_t)
46.Fa "void *tgtmap_priv"
47.Fa "char *tgt_addr"
48.Fa "scsi_tgtmap_tgt_type_t type"
49.Fa "void **tgt_privp"
50.Fc
51.Ft boolean_t
52.Fo (*scsi_tgt_deactivate_cb_t)
53.Fa "void *tgtmap_priv"
54.Fa "char *tgt_addr"
55.Fa "scsi_tgtmap_tgt_type_t type"
56.Fa "void *tgt_priv"
57.Fa "scsi_tgtmap_deact_rsn_t deact"
58.Fc
59.Ft int
60.Fo scsi_hba_tgtmap_set_begin
61.Fa "scsi_hba_tgtmap_t *map"
62.Fc
63.Ft int
64.Fo scsi_hba_tgtmap_set_add
65.Fa "scsi_hba_tgtmap_t *tgtmap"
66.Fa "scsi_tgtmap_tgt_type_t type"
67.Fa "char *tgt_addr"
68.Fa "void *tgt_priv"
69.Fc
70.Ft int
71.Fo scsi_hba_tgtmap_set_end
72.Fa "scsi_hba_tgtmap_t *map"
73.Fc
74.Ft int
75.Fo scsi_hba_tgtmap_set_flush
76.Fa "scsi_hba_tgtmap_t *map"
77.Fc
78.Ft int
79.Fo scsi_hba_tgtmap_tgt_add
80.Fa "scsi_hba_tgtmap_t *tgtmap"
81.Fa "scsi_tgtmap_tgt_type_t type"
82.Fa "char *tgt_addr"
83.Fa "void *tgt_priv"
84.Fc
85.Ft int
86.Fo scsi_hba_tgtmap_tgt_remove
87.Fa "scsi_hba_tgtmap_t *tgtmap"
88.Fa "scsi_tgtmap_tgt_type_t type"
89.Fa "char *tgt_addr"
90.Fc
91.Sh INTERFACE LEVEL
92.Sy Evolving -
93This interface is still evolving in illumos.
94API and ABI stability is
95not guaranteed.
96.Sh PARAMETERS
97.Bl -tag -width Fa
98.It Fa dip
99Pointer to
100.Vt dev_info
101structure.
102.It Fa mode
103One of the following values:
104.Bl -tag -width Dv
105.It Dv SCSI_TM_FULLSET
106The target map operates by full-set reporting.
107.It Dv SCSI_TM_PERADDR
108The target map operates by per-address reporting.
109.El
110.It Fa csync_usec
111A time in microseconds.
112.It Fa settle_usec
113A time in microseconds.
114.It Fa tgtmap_priv
115A private value to be passed to callback functions.
116.It Fa activate_cb
117An optional callback that will be called when a new device is being
118added to the system.
119.It Fa deactivate_cb
120An optional callback that will be called when an existing devices is
121removed from the system.
122.It Fa tgtmapout
123Pointer where the target map is stored.
124.It Fa tgtmap
125Pointer to an allocated target map.
126.It Fa tgt_addr
127The address of the target map entry the callback is acting upon.
128.It Fa type
129One of the following values, indicating the type of the target:
130.Bl -tag -width Dv
131.It Dv SCSI_TGT_SCSI_DEVICE
132The target is some form of SCSI device such as a parallel SCSI, SATA,
133SAS, SES, etc.
134.It Dv SCSI_TGT_SMP_DEVICE
135The target is a SCSI Management Protocol device.
136.El
137.It Fa deact
138One of the following values, indicating why the target is being removed:
139.Bl -tag -width Dv
140.It Dv SCSI_TGT_DEACT_RSN_GONE
141The device is being deactivated because it is gone.
142.It Dv SCSI_TGT_DEACT_RSN_CFG_FAIL
143The device is being deactivated because the configuration callback
144failed.
145.It Dv SCSI_TGT_DEACT_RSN_UNSTBL
146The device is being deactivated because it was added and removed during
147the stabilization period and therefore is considered unstable.
148.El
149.El
150.Sh DESCRIPTION
151The
152.Fn scsi_hba_tgtmap_create
153and
154.Fn scsi_hba_tgtmap_destroy
155functions are used to create and destroy target maps.
156A target map is used to manage SCSI and SMP (SCSI Management Protocol)
157devices.
158For more background on target maps, see
159.Xr tgtmap 9 .
160.Pp
161To create a target map, the driver should call the
162.Fn scsi_hba_tgtmap_create
163function.
164Upon successful completion, a pointer to the target map will be placed
165in the
166.Fa tgtmapout
167argument.
168.Pp
169The
170.Fa dip
171argument should correspond to the HBA driver's device node or one of its
172iports.
173.Pp
174The
175.Fa mode
176argument describes how addresses are reported into the target map and
177the functions used to add and remove devices.
178If
179.Fa mode
180is
181.Dv SCSI_TM_FULLSET
182then the driver must always report all the devices that are in the set
183and will be told when the corresponding devices have been removed.
184See
185the section
186.Sx Full-Set Reporting
187for more information.
188.Pp
189Otherwise, the driver should set the
190.Fa mode
191argument to
192.Dv SCSI_TM_PERADDR
193and use the
194.Fn scsi_hba_tgtmap_tgt_add
195and
196.Fn scsi_hba_tgtmap_tgt_destroy
197functions.
198See the section
199.Sx Per-Address Reporting
200for more information.
201.Pp
202The
203.Fa csync_usec
204and
205.Fa settle_usec
206are both times measured in microseconds that control two different
207properties of the target map and how it behaves.
208The value in
209.Fa settle_usec
210indicates the amount of time that the system should wait to quiesce all
211changes and consider the resulting system stable.
212Changes will not be reported until after
213.Fa settle_usec
214have passed.
215.Fa csync_usec
216indicates how much time needs to elapse after creation before an initial
217enumeration has been completed.
218.Pp
219The
220.Fa activate_cb
221and
222.Fa deactivate_cb
223arguments are optional function pointers that will be run in the context
224of devices being added and removed from the system.
225This allows the HBA driver to perform any required operations prior to
226the system attaching a target driver such as
227.Xr sd 7D
228or
229.Xr ses 7D
230in the activate case and after the system has detached the driver, in
231the removal case.
232.Pp
233To destroy a target map, a caller should use the
234.Fn scsi_hba_tgtmap_destroy
235function.
236Destroying a target map causes all currently present devices
237to be deactivated, as though they were removed, prior to the
238final destruction of the target map.
239.Ss Callbacks
240Target maps allow for callbacks to be registered and called when
241devices are being added and removed from the system.
242A driver specifies these when the target map is created by passing in
243function pointers to
244the
245.Fn activate_cb
246and
247.Fn deactivate_cb
248arguments.
249.Pp
250When a new address is registered in a target map and the driver has
251specified a function in the
252.Fa activate_cb
253argument, the driver will eventually have their activation function
254called.
255This call will be asynchronous with respect to the adding and
256removing of entries, regardless of whether the target map is using
257per-address or full-set reporting.
258This call will occur before any driver is bound to the discovered
259address.
260.Pp
261The
262.Fa tgtmap_priv
263argument will point to the optional, private argument that was passed
264to the
265.Fn scsi_hba_tgtmap_create
266function when the target map was created.
267The
268.Fa tgt_addr
269and
270.Fa tgt_type
271will describe the address and type of the new device and will correspond
272with the values passed into either the
273.Fn scsi_hba_tgtmap_set_add
274or
275.Fn scsi_hba_tgtmap_tgt_add
276functions.
277.Pp
278The
279.Fa tgt_privp
280argument is a modifiable private value.
281Initially,
282.Fa tgt_privp
283points to the value passed in as
284.Fa tgt_priv
285to either the
286.Fn scsi_hba_tgtmap_set_add
287or
288.Fn scsi_hba_tgtmap_tgt_add
289functions.
290The driver may change the value as needed.
291It will receive the value stored in
292.Fa tgt_privp
293during the deactivate callback.
294.Pp
295When a target map has been updated to indicate that a device has been
296removed, then the driver will receive a deactivation callback if it
297registered one.
298The deactivate callback will occur after a driver has
299been detached from the corresponding device.
300.Pp
301The
302.Fa tgtmap_priv ,
303.Fa tgt_addr ,
304and
305.Fa type
306arguments to the callback function are the same as for the activate
307case.
308The
309.Fa tgt_priv
310pointer will be set to the value that was passed when the device was
311added and will reflect any updates made during an activate callback, if
312present.
313.Pp
314The
315.Fa deact
316argument gives the driver some amount of information as to why device
317was being removed.
318The deactivation reason provides the driver
319more information about why the address was being removed from the target
320map which can be useful in the cases that it itself did not issue it.
321.Pp
322The return value indicates whether or not some amount of rediscovery of
323the address is desired or not.
324This is only meaningful in the case where the
325.Fa deact
326argument was
327.Dv SCSI_TGT_DEACT_RSN_CFG_FAIL .
328If the driver does wish to attempt rediscovery, then it should return
329.Dv B_TRUE .
330Otherwise, the driver should return
331.Dv B_FALSE .
332If in doubt, use the return value
333.Dv B_FALSE .
334Note, even if the driver returns
335.Dv B_TRUE ,
336no action may be taken by the system.
337.Ss Full-Set Reporting
338Full-Set reporting is one way of managing a target map.
339In full-set reporting, whenever an update is being made, the entire data
340set is reported to the target map.
341The target map then determines which
342addresses are new, which have been removed, and which have stayed the
343same and updates the system state appropriately.
344If devices have been added or removed from the system, then any activate
345and deactivate endpoints will be called.
346.Pp
347To begin a new report, the driver should call the
348.Fn scsi_hba_tgtmap_set_begin
349function.
350Once the report has begun, the driver should add devices by calling the
351.Fn scsi_hba_tgtmap_set_add
352function.
353Once all devices have been added, the driver should call the
354.Fn scsi_hba_tgtmap_set_end
355function to indicate that the target map processing has ended.
356If driver wishes to discard a report that has begun, but not yet
357terminated, then the driver should call the
358.Fn scsi_hba_tgtmap_set_flush
359function.
360.Pp
361When adding entries, the driver should indicate the address of the
362device in
363.Fa tgt_addr .
364This will generally be a world wide number (WWN) in a unit-addressable
365form.
366However, the driver may use its own synthetic numbering.
367This address will be passed to the activate callbacks and will also be
368used as the address of the
369.Xr scsi_device 9S
370in the
371.Xr tran_start 9E
372entry point.
373.Pp
374The
375.Fa type
376argument indicates how the kernel will interpret the type of device.
377At this time, devices are broken into two broad categories.
378Things which are some kind of SCSI device, whether parallel, SCSI, SATA
379behind a SATL, SES, etc. should use the type
380.Dv SCSI_TGT_SCSI_DEVICE .
381The other group,
382.Dv SCSI_TGT_SMP_DEVICE ,
383is for SCSI Management Protocol (SMP) devices.
384.Pp
385The
386.Fa tgt_priv
387argument will be passed to the activate and deactivate callbacks,
388allowing the driver to pass around data corresponding to this address.
389.Ss Per-Address Reporting
390When using a target map with per-address reporting, the driver is
391responsible for indicating what devices have been added and removed.
392This is useful for various hardware configurations where all entries and
393removals are processes in a highly-reliable fashion where hardware
394cannot drop entries.
395.Pp
396To add a new device, the driver should call the
397.Fa scsi_hba_tgtmap_tgt_add
398function.
399The
400.Fa tgt_addr
401and
402.Fa type
403arguments describe the address and what kind of device the address
404corresponds to.
405For more information, see the previous section,
406.Sx Full-Address Reporting .
407The
408.Fa tgt_priv
409argument will be passed along to the activate and deactivate functions,
410allowing the driver to associate a value with the address in question.
411.Pp
412When a device has been removed, the driver should call the
413.Fn scsi_hba_tgtmap_tgt_remove
414function, ensuring that both the
415.Fa tgt_addr
416and
417.Fa type
418arguments match those that were used when calling the
419.Fn scsi_hba_tgtmap_tgt_add
420function.
421.Sh CONTEXT
422The
423.Fn scsi_hba_tgtmap_create
424and
425.Fn scsi_hba_tgtmap_destroy
426functions are generally called from the context of the
427.Xr attach 9E
428and
429.Xr detach 9E
430entry points of HBA drivers and their iports, though may also be called
431from
432.Sy user
433or
434.Sy kernel
435context.
436.Pp
437The optional
438.Fn activate_cb
439and
440.Fn deactivate_cb
441functions for a target map will be called into the driver from
442.Sy kernel
443context.
444.Pp
445The
446.Fn scsi_hba_tgtmap_set_begin ,
447.Fn scsi_hba_tgtmap_set_add ,
448.Fn scsi_hba_tgtmap_set_end ,
449.Fn scsi_hba_tgtmap_set_flush ,
450.Fn scsi_hba_tgtmap_tgt_add ,
451and
452.Fn scsi_hba_tgtmap_tgt_remove
453functions may be called from
454.Sy user
455or
456.Sy kernel
457context.
458It is recommended that device drivers do not call these functions from
459.Sy interrupt
460context and instead should schedule deferred work with a task queue
461or with
462.Xr timeout 9F
463if they receive notifications during an interrupt that causes them to
464need to call these functions.
465.Sh RETURN VALUES
466Upon successful completion, the
467.Fn scsi_hba_tgtmap_create ,
468.Fn scsi_hba_tgtmap_destroy ,
469.Fn scsi_hba_tgtmap_set_begin ,
470.Fn scsi_hba_tgtmap_set_add ,
471.Fn scsi_hba_tgtmap_set_end ,
472.Fn scsi_hba_tgtmap_set_flush ,
473.Fn scsi_hba_tgtmap_tgt_add ,
474and
475.Fn scsi_hba_tgtmap_tgt_remove
476functions return
477.Dv DDI_SUCCESS .
478Otherwise,
479.Dv DDI_FAILURE
480is returned.
481.Sh SEE ALSO
482.Xr sd 7D ,
483.Xr ses 7D ,
484.Xr tgtmap 9 ,
485.Xr attach 9E ,
486.Xr detach 9E ,
487.Xr tran_start 9E ,
488.Xr timeout 9F ,
489.Xr scsi_device 9S
490