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-rw-r--r--Documentation/DocBook/Makefile3
-rw-r--r--Documentation/DocBook/genericirq.tmpl474
-rw-r--r--Documentation/IRQ.txt22
-rw-r--r--Documentation/kernel-parameters.txt9
-rw-r--r--Documentation/keys-request-key.txt54
-rw-r--r--Documentation/keys.txt29
-rw-r--r--Documentation/sound/alsa/ALSA-Configuration.txt106
7 files changed, 674 insertions, 23 deletions
diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile
index 5a2882d275ba..66e1cf733571 100644
--- a/Documentation/DocBook/Makefile
+++ b/Documentation/DocBook/Makefile
@@ -10,7 +10,8 @@ DOCBOOKS := wanbook.xml z8530book.xml mcabook.xml videobook.xml \
10 kernel-hacking.xml kernel-locking.xml deviceiobook.xml \ 10 kernel-hacking.xml kernel-locking.xml deviceiobook.xml \
11 procfs-guide.xml writing_usb_driver.xml \ 11 procfs-guide.xml writing_usb_driver.xml \
12 kernel-api.xml journal-api.xml lsm.xml usb.xml \ 12 kernel-api.xml journal-api.xml lsm.xml usb.xml \
13 gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml 13 gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \
14 genericirq.xml
14 15
15### 16###
16# The build process is as follows (targets): 17# The build process is as follows (targets):
diff --git a/Documentation/DocBook/genericirq.tmpl b/Documentation/DocBook/genericirq.tmpl
new file mode 100644
index 000000000000..0f4a4b6321e4
--- /dev/null
+++ b/Documentation/DocBook/genericirq.tmpl
@@ -0,0 +1,474 @@
1<?xml version="1.0" encoding="UTF-8"?>
2<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
4
5<book id="Generic-IRQ-Guide">
6 <bookinfo>
7 <title>Linux generic IRQ handling</title>
8
9 <authorgroup>
10 <author>
11 <firstname>Thomas</firstname>
12 <surname>Gleixner</surname>
13 <affiliation>
14 <address>
15 <email>tglx@linutronix.de</email>
16 </address>
17 </affiliation>
18 </author>
19 <author>
20 <firstname>Ingo</firstname>
21 <surname>Molnar</surname>
22 <affiliation>
23 <address>
24 <email>mingo@elte.hu</email>
25 </address>
26 </affiliation>
27 </author>
28 </authorgroup>
29
30 <copyright>
31 <year>2005-2006</year>
32 <holder>Thomas Gleixner</holder>
33 </copyright>
34 <copyright>
35 <year>2005-2006</year>
36 <holder>Ingo Molnar</holder>
37 </copyright>
38
39 <legalnotice>
40 <para>
41 This documentation is free software; you can redistribute
42 it and/or modify it under the terms of the GNU General Public
43 License version 2 as published by the Free Software Foundation.
44 </para>
45
46 <para>
47 This program is distributed in the hope that it will be
48 useful, but WITHOUT ANY WARRANTY; without even the implied
49 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
50 See the GNU General Public License for more details.
51 </para>
52
53 <para>
54 You should have received a copy of the GNU General Public
55 License along with this program; if not, write to the Free
56 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
57 MA 02111-1307 USA
58 </para>
59
60 <para>
61 For more details see the file COPYING in the source
62 distribution of Linux.
63 </para>
64 </legalnotice>
65 </bookinfo>
66
67<toc></toc>
68
69 <chapter id="intro">
70 <title>Introduction</title>
71 <para>
72 The generic interrupt handling layer is designed to provide a
73 complete abstraction of interrupt handling for device drivers.
74 It is able to handle all the different types of interrupt controller
75 hardware. Device drivers use generic API functions to request, enable,
76 disable and free interrupts. The drivers do not have to know anything
77 about interrupt hardware details, so they can be used on different
78 platforms without code changes.
79 </para>
80 <para>
81 This documentation is provided to developers who want to implement
82 an interrupt subsystem based for their architecture, with the help
83 of the generic IRQ handling layer.
84 </para>
85 </chapter>
86
87 <chapter id="rationale">
88 <title>Rationale</title>
89 <para>
90 The original implementation of interrupt handling in Linux is using
91 the __do_IRQ() super-handler, which is able to deal with every
92 type of interrupt logic.
93 </para>
94 <para>
95 Originally, Russell King identified different types of handlers to
96 build a quite universal set for the ARM interrupt handler
97 implementation in Linux 2.5/2.6. He distinguished between:
98 <itemizedlist>
99 <listitem><para>Level type</para></listitem>
100 <listitem><para>Edge type</para></listitem>
101 <listitem><para>Simple type</para></listitem>
102 </itemizedlist>
103 In the SMP world of the __do_IRQ() super-handler another type
104 was identified:
105 <itemizedlist>
106 <listitem><para>Per CPU type</para></listitem>
107 </itemizedlist>
108 </para>
109 <para>
110 This split implementation of highlevel IRQ handlers allows us to
111 optimize the flow of the interrupt handling for each specific
112 interrupt type. This reduces complexity in that particular codepath
113 and allows the optimized handling of a given type.
114 </para>
115 <para>
116 The original general IRQ implementation used hw_interrupt_type
117 structures and their ->ack(), ->end() [etc.] callbacks to
118 differentiate the flow control in the super-handler. This leads to
119 a mix of flow logic and lowlevel hardware logic, and it also leads
120 to unnecessary code duplication: for example in i386, there is a
121 ioapic_level_irq and a ioapic_edge_irq irq-type which share many
122 of the lowlevel details but have different flow handling.
123 </para>
124 <para>
125 A more natural abstraction is the clean separation of the
126 'irq flow' and the 'chip details'.
127 </para>
128 <para>
129 Analysing a couple of architecture's IRQ subsystem implementations
130 reveals that most of them can use a generic set of 'irq flow'
131 methods and only need to add the chip level specific code.
132 The separation is also valuable for (sub)architectures
133 which need specific quirks in the irq flow itself but not in the
134 chip-details - and thus provides a more transparent IRQ subsystem
135 design.
136 </para>
137 <para>
138 Each interrupt descriptor is assigned its own highlevel flow
139 handler, which is normally one of the generic
140 implementations. (This highlevel flow handler implementation also
141 makes it simple to provide demultiplexing handlers which can be
142 found in embedded platforms on various architectures.)
143 </para>
144 <para>
145 The separation makes the generic interrupt handling layer more
146 flexible and extensible. For example, an (sub)architecture can
147 use a generic irq-flow implementation for 'level type' interrupts
148 and add a (sub)architecture specific 'edge type' implementation.
149 </para>
150 <para>
151 To make the transition to the new model easier and prevent the
152 breakage of existing implementations, the __do_IRQ() super-handler
153 is still available. This leads to a kind of duality for the time
154 being. Over time the new model should be used in more and more
155 architectures, as it enables smaller and cleaner IRQ subsystems.
156 </para>
157 </chapter>
158 <chapter id="bugs">
159 <title>Known Bugs And Assumptions</title>
160 <para>
161 None (knock on wood).
162 </para>
163 </chapter>
164
165 <chapter id="Abstraction">
166 <title>Abstraction layers</title>
167 <para>
168 There are three main levels of abstraction in the interrupt code:
169 <orderedlist>
170 <listitem><para>Highlevel driver API</para></listitem>
171 <listitem><para>Highlevel IRQ flow handlers</para></listitem>
172 <listitem><para>Chiplevel hardware encapsulation</para></listitem>
173 </orderedlist>
174 </para>
175 <sect1>
176 <title>Interrupt control flow</title>
177 <para>
178 Each interrupt is described by an interrupt descriptor structure
179 irq_desc. The interrupt is referenced by an 'unsigned int' numeric
180 value which selects the corresponding interrupt decription structure
181 in the descriptor structures array.
182 The descriptor structure contains status information and pointers
183 to the interrupt flow method and the interrupt chip structure
184 which are assigned to this interrupt.
185 </para>
186 <para>
187 Whenever an interrupt triggers, the lowlevel arch code calls into
188 the generic interrupt code by calling desc->handle_irq().
189 This highlevel IRQ handling function only uses desc->chip primitives
190 referenced by the assigned chip descriptor structure.
191 </para>
192 </sect1>
193 <sect1>
194 <title>Highlevel Driver API</title>
195 <para>
196 The highlevel Driver API consists of following functions:
197 <itemizedlist>
198 <listitem><para>request_irq()</para></listitem>
199 <listitem><para>free_irq()</para></listitem>
200 <listitem><para>disable_irq()</para></listitem>
201 <listitem><para>enable_irq()</para></listitem>
202 <listitem><para>disable_irq_nosync() (SMP only)</para></listitem>
203 <listitem><para>synchronize_irq() (SMP only)</para></listitem>
204 <listitem><para>set_irq_type()</para></listitem>
205 <listitem><para>set_irq_wake()</para></listitem>
206 <listitem><para>set_irq_data()</para></listitem>
207 <listitem><para>set_irq_chip()</para></listitem>
208 <listitem><para>set_irq_chip_data()</para></listitem>
209 </itemizedlist>
210 See the autogenerated function documentation for details.
211 </para>
212 </sect1>
213 <sect1>
214 <title>Highlevel IRQ flow handlers</title>
215 <para>
216 The generic layer provides a set of pre-defined irq-flow methods:
217 <itemizedlist>
218 <listitem><para>handle_level_irq</para></listitem>
219 <listitem><para>handle_edge_irq</para></listitem>
220 <listitem><para>handle_simple_irq</para></listitem>
221 <listitem><para>handle_percpu_irq</para></listitem>
222 </itemizedlist>
223 The interrupt flow handlers (either predefined or architecture
224 specific) are assigned to specific interrupts by the architecture
225 either during bootup or during device initialization.
226 </para>
227 <sect2>
228 <title>Default flow implementations</title>
229 <sect3>
230 <title>Helper functions</title>
231 <para>
232 The helper functions call the chip primitives and
233 are used by the default flow implementations.
234 The following helper functions are implemented (simplified excerpt):
235 <programlisting>
236default_enable(irq)
237{
238 desc->chip->unmask(irq);
239}
240
241default_disable(irq)
242{
243 if (!delay_disable(irq))
244 desc->chip->mask(irq);
245}
246
247default_ack(irq)
248{
249 chip->ack(irq);
250}
251
252default_mask_ack(irq)
253{
254 if (chip->mask_ack) {
255 chip->mask_ack(irq);
256 } else {
257 chip->mask(irq);
258 chip->ack(irq);
259 }
260}
261
262noop(irq)
263{
264}
265
266 </programlisting>
267 </para>
268 </sect3>
269 </sect2>
270 <sect2>
271 <title>Default flow handler implementations</title>
272 <sect3>
273 <title>Default Level IRQ flow handler</title>
274 <para>
275 handle_level_irq provides a generic implementation
276 for level-triggered interrupts.
277 </para>
278 <para>
279 The following control flow is implemented (simplified excerpt):
280 <programlisting>
281desc->chip->start();
282handle_IRQ_event(desc->action);
283desc->chip->end();
284 </programlisting>
285 </para>
286 </sect3>
287 <sect3>
288 <title>Default Edge IRQ flow handler</title>
289 <para>
290 handle_edge_irq provides a generic implementation
291 for edge-triggered interrupts.
292 </para>
293 <para>
294 The following control flow is implemented (simplified excerpt):
295 <programlisting>
296if (desc->status &amp; running) {
297 desc->chip->hold();
298 desc->status |= pending | masked;
299 return;
300}
301desc->chip->start();
302desc->status |= running;
303do {
304 if (desc->status &amp; masked)
305 desc->chip->enable();
306 desc-status &amp;= ~pending;
307 handle_IRQ_event(desc->action);
308} while (status &amp; pending);
309desc-status &amp;= ~running;
310desc->chip->end();
311 </programlisting>
312 </para>
313 </sect3>
314 <sect3>
315 <title>Default simple IRQ flow handler</title>
316 <para>
317 handle_simple_irq provides a generic implementation
318 for simple interrupts.
319 </para>
320 <para>
321 Note: The simple flow handler does not call any
322 handler/chip primitives.
323 </para>
324 <para>
325 The following control flow is implemented (simplified excerpt):
326 <programlisting>
327handle_IRQ_event(desc->action);
328 </programlisting>
329 </para>
330 </sect3>
331 <sect3>
332 <title>Default per CPU flow handler</title>
333 <para>
334 handle_percpu_irq provides a generic implementation
335 for per CPU interrupts.
336 </para>
337 <para>
338 Per CPU interrupts are only available on SMP and
339 the handler provides a simplified version without
340 locking.
341 </para>
342 <para>
343 The following control flow is implemented (simplified excerpt):
344 <programlisting>
345desc->chip->start();
346handle_IRQ_event(desc->action);
347desc->chip->end();
348 </programlisting>
349 </para>
350 </sect3>
351 </sect2>
352 <sect2>
353 <title>Quirks and optimizations</title>
354 <para>
355 The generic functions are intended for 'clean' architectures and chips,
356 which have no platform-specific IRQ handling quirks. If an architecture
357 needs to implement quirks on the 'flow' level then it can do so by
358 overriding the highlevel irq-flow handler.
359 </para>
360 </sect2>
361 <sect2>
362 <title>Delayed interrupt disable</title>
363 <para>
364 This per interrupt selectable feature, which was introduced by Russell
365 King in the ARM interrupt implementation, does not mask an interrupt
366 at the hardware level when disable_irq() is called. The interrupt is
367 kept enabled and is masked in the flow handler when an interrupt event
368 happens. This prevents losing edge interrupts on hardware which does
369 not store an edge interrupt event while the interrupt is disabled at
370 the hardware level. When an interrupt arrives while the IRQ_DISABLED
371 flag is set, then the interrupt is masked at the hardware level and
372 the IRQ_PENDING bit is set. When the interrupt is re-enabled by
373 enable_irq() the pending bit is checked and if it is set, the
374 interrupt is resent either via hardware or by a software resend
375 mechanism. (It's necessary to enable CONFIG_HARDIRQS_SW_RESEND when
376 you want to use the delayed interrupt disable feature and your
377 hardware is not capable of retriggering an interrupt.)
378 The delayed interrupt disable can be runtime enabled, per interrupt,
379 by setting the IRQ_DELAYED_DISABLE flag in the irq_desc status field.
380 </para>
381 </sect2>
382 </sect1>
383 <sect1>
384 <title>Chiplevel hardware encapsulation</title>
385 <para>
386 The chip level hardware descriptor structure irq_chip
387 contains all the direct chip relevant functions, which
388 can be utilized by the irq flow implementations.
389 <itemizedlist>
390 <listitem><para>ack()</para></listitem>
391 <listitem><para>mask_ack() - Optional, recommended for performance</para></listitem>
392 <listitem><para>mask()</para></listitem>
393 <listitem><para>unmask()</para></listitem>
394 <listitem><para>retrigger() - Optional</para></listitem>
395 <listitem><para>set_type() - Optional</para></listitem>
396 <listitem><para>set_wake() - Optional</para></listitem>
397 </itemizedlist>
398 These primitives are strictly intended to mean what they say: ack means
399 ACK, masking means masking of an IRQ line, etc. It is up to the flow
400 handler(s) to use these basic units of lowlevel functionality.
401 </para>
402 </sect1>
403 </chapter>
404
405 <chapter id="doirq">
406 <title>__do_IRQ entry point</title>
407 <para>
408 The original implementation __do_IRQ() is an alternative entry
409 point for all types of interrupts.
410 </para>
411 <para>
412 This handler turned out to be not suitable for all
413 interrupt hardware and was therefore reimplemented with split
414 functionality for egde/level/simple/percpu interrupts. This is not
415 only a functional optimization. It also shortens code paths for
416 interrupts.
417 </para>
418 <para>
419 To make use of the split implementation, replace the call to
420 __do_IRQ by a call to desc->chip->handle_irq() and associate
421 the appropriate handler function to desc->chip->handle_irq().
422 In most cases the generic handler implementations should
423 be sufficient.
424 </para>
425 </chapter>
426
427 <chapter id="locking">
428 <title>Locking on SMP</title>
429 <para>
430 The locking of chip registers is up to the architecture that
431 defines the chip primitives. There is a chip->lock field that can be used
432 for serialization, but the generic layer does not touch it. The per-irq
433 structure is protected via desc->lock, by the generic layer.
434 </para>
435 </chapter>
436 <chapter id="structs">
437 <title>Structures</title>
438 <para>
439 This chapter contains the autogenerated documentation of the structures which are
440 used in the generic IRQ layer.
441 </para>
442!Iinclude/linux/irq.h
443 </chapter>
444
445 <chapter id="pubfunctions">
446 <title>Public Functions Provided</title>
447 <para>
448 This chapter contains the autogenerated documentation of the kernel API functions
449 which are exported.
450 </para>
451!Ekernel/irq/manage.c
452!Ekernel/irq/chip.c
453 </chapter>
454
455 <chapter id="intfunctions">
456 <title>Internal Functions Provided</title>
457 <para>
458 This chapter contains the autogenerated documentation of the internal functions.
459 </para>
460!Ikernel/irq/handle.c
461!Ikernel/irq/chip.c
462 </chapter>
463
464 <chapter id="credits">
465 <title>Credits</title>
466 <para>
467 The following people have contributed to this document:
468 <orderedlist>
469 <listitem><para>Thomas Gleixner<email>tglx@linutronix.de</email></para></listitem>
470 <listitem><para>Ingo Molnar<email>mingo@elte.hu</email></para></listitem>
471 </orderedlist>
472 </para>
473 </chapter>
474</book>
diff --git a/Documentation/IRQ.txt b/Documentation/IRQ.txt
new file mode 100644
index 000000000000..1011e7175021
--- /dev/null
+++ b/Documentation/IRQ.txt
@@ -0,0 +1,22 @@
1What is an IRQ?
2
3An IRQ is an interrupt request from a device.
4Currently they can come in over a pin, or over a packet.
5Several devices may be connected to the same pin thus
6sharing an IRQ.
7
8An IRQ number is a kernel identifier used to talk about a hardware
9interrupt source. Typically this is an index into the global irq_desc
10array, but except for what linux/interrupt.h implements the details
11are architecture specific.
12
13An IRQ number is an enumeration of the possible interrupt sources on a
14machine. Typically what is enumerated is the number of input pins on
15all of the interrupt controller in the system. In the case of ISA
16what is enumerated are the 16 input pins on the two i8259 interrupt
17controllers.
18
19Architectures can assign additional meaning to the IRQ numbers, and
20are encouraged to in the case where there is any manual configuration
21of the hardware involved. The ISA IRQs are a classic example of
22assigning this kind of additional meaning.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 0d189c93eeaf..25f8d20dac53 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1689,9 +1689,14 @@ running once the system is up.
1689 decrease the size and leave more room for directly 1689 decrease the size and leave more room for directly
1690 mapped kernel RAM. 1690 mapped kernel RAM.
1691 1691
1692 vmhalt= [KNL,S390] 1692 vmhalt= [KNL,S390] Perform z/VM CP command after system halt.
1693 Format: <command>
1693 1694
1694 vmpoff= [KNL,S390] 1695 vmpanic= [KNL,S390] Perform z/VM CP command after kernel panic.
1696 Format: <command>
1697
1698 vmpoff= [KNL,S390] Perform z/VM CP command after power off.
1699 Format: <command>
1695 1700
1696 waveartist= [HW,OSS] 1701 waveartist= [HW,OSS]
1697 Format: <io>,<irq>,<dma>,<dma2> 1702 Format: <io>,<irq>,<dma>,<dma2>
diff --git a/Documentation/keys-request-key.txt b/Documentation/keys-request-key.txt
index 22488d791168..c1f64fdf84cb 100644
--- a/Documentation/keys-request-key.txt
+++ b/Documentation/keys-request-key.txt
@@ -3,16 +3,23 @@
3 =================== 3 ===================
4 4
5The key request service is part of the key retention service (refer to 5The key request service is part of the key retention service (refer to
6Documentation/keys.txt). This document explains more fully how that the 6Documentation/keys.txt). This document explains more fully how the requesting
7requesting algorithm works. 7algorithm works.
8 8
9The process starts by either the kernel requesting a service by calling 9The process starts by either the kernel requesting a service by calling
10request_key(): 10request_key*():
11 11
12 struct key *request_key(const struct key_type *type, 12 struct key *request_key(const struct key_type *type,
13 const char *description, 13 const char *description,
14 const char *callout_string); 14 const char *callout_string);
15 15
16or:
17
18 struct key *request_key_with_auxdata(const struct key_type *type,
19 const char *description,
20 const char *callout_string,
21 void *aux);
22
16Or by userspace invoking the request_key system call: 23Or by userspace invoking the request_key system call:
17 24
18 key_serial_t request_key(const char *type, 25 key_serial_t request_key(const char *type,
@@ -20,16 +27,26 @@ Or by userspace invoking the request_key system call:
20 const char *callout_info, 27 const char *callout_info,
21 key_serial_t dest_keyring); 28 key_serial_t dest_keyring);
22 29
23The main difference between the two access points is that the in-kernel 30The main difference between the access points is that the in-kernel interface
24interface does not need to link the key to a keyring to prevent it from being 31does not need to link the key to a keyring to prevent it from being immediately
25immediately destroyed. The kernel interface returns a pointer directly to the 32destroyed. The kernel interface returns a pointer directly to the key, and
26key, and it's up to the caller to destroy the key. 33it's up to the caller to destroy the key.
34
35The request_key_with_auxdata() call is like the in-kernel request_key() call,
36except that it permits auxiliary data to be passed to the upcaller (the default
37is NULL). This is only useful for those key types that define their own upcall
38mechanism rather than using /sbin/request-key.
27 39
28The userspace interface links the key to a keyring associated with the process 40The userspace interface links the key to a keyring associated with the process
29to prevent the key from going away, and returns the serial number of the key to 41to prevent the key from going away, and returns the serial number of the key to
30the caller. 42the caller.
31 43
32 44
45The following example assumes that the key types involved don't define their
46own upcall mechanisms. If they do, then those should be substituted for the
47forking and execution of /sbin/request-key.
48
49
33=========== 50===========
34THE PROCESS 51THE PROCESS
35=========== 52===========
@@ -40,8 +57,8 @@ A request proceeds in the following manner:
40 interface]. 57 interface].
41 58
42 (2) request_key() searches the process's subscribed keyrings to see if there's 59 (2) request_key() searches the process's subscribed keyrings to see if there's
43 a suitable key there. If there is, it returns the key. If there isn't, and 60 a suitable key there. If there is, it returns the key. If there isn't,
44 callout_info is not set, an error is returned. Otherwise the process 61 and callout_info is not set, an error is returned. Otherwise the process
45 proceeds to the next step. 62 proceeds to the next step.
46 63
47 (3) request_key() sees that A doesn't have the desired key yet, so it creates 64 (3) request_key() sees that A doesn't have the desired key yet, so it creates
@@ -62,7 +79,7 @@ A request proceeds in the following manner:
62 instantiation. 79 instantiation.
63 80
64 (7) The program may want to access another key from A's context (say a 81 (7) The program may want to access another key from A's context (say a
65 Kerberos TGT key). It just requests the appropriate key, and the keyring 82 Kerberos TGT key). It just requests the appropriate key, and the keyring
66 search notes that the session keyring has auth key V in its bottom level. 83 search notes that the session keyring has auth key V in its bottom level.
67 84
68 This will permit it to then search the keyrings of process A with the 85 This will permit it to then search the keyrings of process A with the
@@ -79,10 +96,11 @@ A request proceeds in the following manner:
79(10) The program then exits 0 and request_key() deletes key V and returns key 96(10) The program then exits 0 and request_key() deletes key V and returns key
80 U to the caller. 97 U to the caller.
81 98
82This also extends further. If key W (step 7 above) didn't exist, key W would be 99This also extends further. If key W (step 7 above) didn't exist, key W would
83created uninstantiated, another auth key (X) would be created (as per step 3) 100be created uninstantiated, another auth key (X) would be created (as per step
84and another copy of /sbin/request-key spawned (as per step 4); but the context 1013) and another copy of /sbin/request-key spawned (as per step 4); but the
85specified by auth key X will still be process A, as it was in auth key V. 102context specified by auth key X will still be process A, as it was in auth key
103V.
86 104
87This is because process A's keyrings can't simply be attached to 105This is because process A's keyrings can't simply be attached to
88/sbin/request-key at the appropriate places because (a) execve will discard two 106/sbin/request-key at the appropriate places because (a) execve will discard two
@@ -118,17 +136,17 @@ A search of any particular keyring proceeds in the following fashion:
118 136
119 (2) It considers all the non-keyring keys within that keyring and, if any key 137 (2) It considers all the non-keyring keys within that keyring and, if any key
120 matches the criteria specified, calls key_permission(SEARCH) on it to see 138 matches the criteria specified, calls key_permission(SEARCH) on it to see
121 if the key is allowed to be found. If it is, that key is returned; if 139 if the key is allowed to be found. If it is, that key is returned; if
122 not, the search continues, and the error code is retained if of higher 140 not, the search continues, and the error code is retained if of higher
123 priority than the one currently set. 141 priority than the one currently set.
124 142
125 (3) It then considers all the keyring-type keys in the keyring it's currently 143 (3) It then considers all the keyring-type keys in the keyring it's currently
126 searching. It calls key_permission(SEARCH) on each keyring, and if this 144 searching. It calls key_permission(SEARCH) on each keyring, and if this
127 grants permission, it recurses, executing steps (2) and (3) on that 145 grants permission, it recurses, executing steps (2) and (3) on that
128 keyring. 146 keyring.
129 147
130The process stops immediately a valid key is found with permission granted to 148The process stops immediately a valid key is found with permission granted to
131use it. Any error from a previous match attempt is discarded and the key is 149use it. Any error from a previous match attempt is discarded and the key is
132returned. 150returned.
133 151
134When search_process_keyrings() is invoked, it performs the following searches 152When search_process_keyrings() is invoked, it performs the following searches
@@ -153,7 +171,7 @@ The moment one succeeds, all pending errors are discarded and the found key is
153returned. 171returned.
154 172
155Only if all these fail does the whole thing fail with the highest priority 173Only if all these fail does the whole thing fail with the highest priority
156error. Note that several errors may have come from LSM. 174error. Note that several errors may have come from LSM.
157 175
158The error priority is: 176The error priority is:
159 177
diff --git a/Documentation/keys.txt b/Documentation/keys.txt
index 61c0fad2fe2f..e373f0212843 100644
--- a/Documentation/keys.txt
+++ b/Documentation/keys.txt
@@ -780,6 +780,17 @@ payload contents" for more information.
780 See also Documentation/keys-request-key.txt. 780 See also Documentation/keys-request-key.txt.
781 781
782 782
783(*) To search for a key, passing auxiliary data to the upcaller, call:
784
785 struct key *request_key_with_auxdata(const struct key_type *type,
786 const char *description,
787 const char *callout_string,
788 void *aux);
789
790 This is identical to request_key(), except that the auxiliary data is
791 passed to the key_type->request_key() op if it exists.
792
793
783(*) When it is no longer required, the key should be released using: 794(*) When it is no longer required, the key should be released using:
784 795
785 void key_put(struct key *key); 796 void key_put(struct key *key);
@@ -1031,6 +1042,24 @@ The structure has a number of fields, some of which are mandatory:
1031 as might happen when the userspace buffer is accessed. 1042 as might happen when the userspace buffer is accessed.
1032 1043
1033 1044
1045 (*) int (*request_key)(struct key *key, struct key *authkey, const char *op,
1046 void *aux);
1047
1048 This method is optional. If provided, request_key() and
1049 request_key_with_auxdata() will invoke this function rather than
1050 upcalling to /sbin/request-key to operate upon a key of this type.
1051
1052 The aux parameter is as passed to request_key_with_auxdata() or is NULL
1053 otherwise. Also passed are the key to be operated upon, the
1054 authorisation key for this operation and the operation type (currently
1055 only "create").
1056
1057 This function should return only when the upcall is complete. Upon return
1058 the authorisation key will be revoked, and the target key will be
1059 negatively instantiated if it is still uninstantiated. The error will be
1060 returned to the caller of request_key*().
1061
1062
1034============================ 1063============================
1035REQUEST-KEY CALLBACK SERVICE 1064REQUEST-KEY CALLBACK SERVICE
1036============================ 1065============================
diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt
index 87d76a5c73d0..f61af23dd85d 100644
--- a/Documentation/sound/alsa/ALSA-Configuration.txt
+++ b/Documentation/sound/alsa/ALSA-Configuration.txt
@@ -472,6 +472,22 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
472 472
473 The power-management is supported. 473 The power-management is supported.
474 474
475 Module snd-darla20
476 ------------------
477
478 Module for Echoaudio Darla20
479
480 This module supports multiple cards.
481 The driver requires the firmware loader support on kernel.
482
483 Module snd-darla24
484 ------------------
485
486 Module for Echoaudio Darla24
487
488 This module supports multiple cards.
489 The driver requires the firmware loader support on kernel.
490
475 Module snd-dt019x 491 Module snd-dt019x
476 ----------------- 492 -----------------
477 493
@@ -499,6 +515,14 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
499 515
500 The power-management is supported. 516 The power-management is supported.
501 517
518 Module snd-echo3g
519 -----------------
520
521 Module for Echoaudio 3G cards (Gina3G/Layla3G)
522
523 This module supports multiple cards.
524 The driver requires the firmware loader support on kernel.
525
502 Module snd-emu10k1 526 Module snd-emu10k1
503 ------------------ 527 ------------------
504 528
@@ -657,6 +681,22 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
657 681
658 The power-management is supported. 682 The power-management is supported.
659 683
684 Module snd-gina20
685 -----------------
686
687 Module for Echoaudio Gina20
688
689 This module supports multiple cards.
690 The driver requires the firmware loader support on kernel.
691
692 Module snd-gina24
693 -----------------
694
695 Module for Echoaudio Gina24
696
697 This module supports multiple cards.
698 The driver requires the firmware loader support on kernel.
699
660 Module snd-gusclassic 700 Module snd-gusclassic
661 --------------------- 701 ---------------------
662 702
@@ -760,12 +800,18 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
760 basic fixed pin assignment w/o SPDIF 800 basic fixed pin assignment w/o SPDIF
761 auto auto-config reading BIOS (default) 801 auto auto-config reading BIOS (default)
762 802
763 ALC882/883/885 803 ALC882/885
764 3stack-dig 3-jack with SPDIF I/O 804 3stack-dig 3-jack with SPDIF I/O
765 6stck-dig 6-jack digital with SPDIF I/O 805 6stck-dig 6-jack digital with SPDIF I/O
766 auto auto-config reading BIOS (default) 806 auto auto-config reading BIOS (default)
767 807
768 ALC861 808 ALC883/888
809 3stack-dig 3-jack with SPDIF I/O
810 6stack-dig 6-jack digital with SPDIF I/O
811 6stack-dig-demo 6-stack digital for Intel demo board
812 auto auto-config reading BIOS (default)
813
814 ALC861/660
769 3stack 3-jack 815 3stack 3-jack
770 3stack-dig 3-jack with SPDIF I/O 816 3stack-dig 3-jack with SPDIF I/O
771 6stack-dig 6-jack with SPDIF I/O 817 6stack-dig 6-jack with SPDIF I/O
@@ -937,6 +983,30 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
937 driver isn't configured properly or you want to try another 983 driver isn't configured properly or you want to try another
938 type for testing. 984 type for testing.
939 985
986 Module snd-indigo
987 -----------------
988
989 Module for Echoaudio Indigo
990
991 This module supports multiple cards.
992 The driver requires the firmware loader support on kernel.
993
994 Module snd-indigodj
995 -------------------
996
997 Module for Echoaudio Indigo DJ
998
999 This module supports multiple cards.
1000 The driver requires the firmware loader support on kernel.
1001
1002 Module snd-indigoio
1003 -------------------
1004
1005 Module for Echoaudio Indigo IO
1006
1007 This module supports multiple cards.
1008 The driver requires the firmware loader support on kernel.
1009
940 Module snd-intel8x0 1010 Module snd-intel8x0
941 ------------------- 1011 -------------------
942 1012
@@ -1036,6 +1106,22 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
1036 1106
1037 This module supports multiple cards. 1107 This module supports multiple cards.
1038 1108
1109 Module snd-layla20
1110 ------------------
1111
1112 Module for Echoaudio Layla20
1113
1114 This module supports multiple cards.
1115 The driver requires the firmware loader support on kernel.
1116
1117 Module snd-layla24
1118 ------------------
1119
1120 Module for Echoaudio Layla24
1121
1122 This module supports multiple cards.
1123 The driver requires the firmware loader support on kernel.
1124
1039 Module snd-maestro3 1125 Module snd-maestro3
1040 ------------------- 1126 -------------------
1041 1127
@@ -1056,6 +1142,14 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
1056 1142
1057 The power-management is supported. 1143 The power-management is supported.
1058 1144
1145 Module snd-mia
1146 ---------------
1147
1148 Module for Echoaudio Mia
1149
1150 This module supports multiple cards.
1151 The driver requires the firmware loader support on kernel.
1152
1059 Module snd-miro 1153 Module snd-miro
1060 --------------- 1154 ---------------
1061 1155
@@ -1088,6 +1182,14 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
1088 When no hotplug fw loader is available, you need to load the 1182 When no hotplug fw loader is available, you need to load the
1089 firmware via mixartloader utility in alsa-tools package. 1183 firmware via mixartloader utility in alsa-tools package.
1090 1184
1185 Module snd-mona
1186 ---------------
1187
1188 Module for Echoaudio Mona
1189
1190 This module supports multiple cards.
1191 The driver requires the firmware loader support on kernel.
1192
1091 Module snd-mpu401 1193 Module snd-mpu401
1092 ----------------- 1194 -----------------
1093 1195