Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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="LinuxKernelAPI">
6 <bookinfo>
7 <title>The Linux Kernel API</title>
8
9 <legalnotice>
10 <para>
11 This documentation is free software; you can redistribute
12 it and/or modify it under the terms of the GNU General Public
13 License as published by the Free Software Foundation; either
14 version 2 of the License, or (at your option) any later
15 version.
16 </para>
17
18 <para>
19 This program is distributed in the hope that it will be
20 useful, but WITHOUT ANY WARRANTY; without even the implied
21 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 See the GNU General Public License for more details.
23 </para>
24
25 <para>
26 You should have received a copy of the GNU General Public
27 License along with this program; if not, write to the Free
28 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
29 MA 02111-1307 USA
30 </para>
31
32 <para>
33 For more details see the file COPYING in the source
34 distribution of Linux.
35 </para>
36 </legalnotice>
37 </bookinfo>
38
39<toc></toc>
40
41 <chapter id="Basics">
42 <title>Driver Basics</title>
43 <sect1><title>Driver Entry and Exit points</title>
44!Iinclude/linux/init.h
45 </sect1>
46
47 <sect1><title>Atomic and pointer manipulation</title>
48!Iinclude/asm-i386/atomic.h
49!Iinclude/asm-i386/unaligned.h
50 </sect1>
51
52 <sect1><title>Delaying, scheduling, and timer routines</title>
53!Iinclude/linux/sched.h
54!Ekernel/sched.c
55!Ekernel/timer.c
56 </sect1>
57 <sect1><title>High-resolution timers</title>
58!Iinclude/linux/ktime.h
59!Iinclude/linux/hrtimer.h
60!Ekernel/hrtimer.c
61 </sect1>
62 <sect1><title>Workqueues and Kevents</title>
63!Ekernel/workqueue.c
64 </sect1>
65 <sect1><title>Internal Functions</title>
66!Ikernel/exit.c
67!Ikernel/signal.c
68!Iinclude/linux/kthread.h
69!Ekernel/kthread.c
70 </sect1>
71
72 <sect1><title>Kernel objects manipulation</title>
73<!--
74X!Iinclude/linux/kobject.h
75-->
76!Elib/kobject.c
77 </sect1>
78
79 <sect1><title>Kernel utility functions</title>
80!Iinclude/linux/kernel.h
81!Ekernel/printk.c
82!Ekernel/panic.c
83!Ekernel/sys.c
84!Ekernel/rcupdate.c
85 </sect1>
86
87 <sect1><title>Device Resource Management</title>
88!Edrivers/base/devres.c
89 </sect1>
90
91 </chapter>
92
93 <chapter id="adt">
94 <title>Data Types</title>
95 <sect1><title>Doubly Linked Lists</title>
96!Iinclude/linux/list.h
97 </sect1>
98 </chapter>
99
100 <chapter id="libc">
101 <title>Basic C Library Functions</title>
102
103 <para>
104 When writing drivers, you cannot in general use routines which are
105 from the C Library. Some of the functions have been found generally
106 useful and they are listed below. The behaviour of these functions
107 may vary slightly from those defined by ANSI, and these deviations
108 are noted in the text.
109 </para>
110
111 <sect1><title>String Conversions</title>
112!Ilib/vsprintf.c
113!Elib/vsprintf.c
114 </sect1>
115 <sect1><title>String Manipulation</title>
116<!-- All functions are exported at now
117X!Ilib/string.c
118 -->
119!Elib/string.c
120 </sect1>
121 <sect1><title>Bit Operations</title>
122!Iinclude/asm-i386/bitops.h
123 </sect1>
124 </chapter>
125
126 <chapter id="kernel-lib">
127 <title>Basic Kernel Library Functions</title>
128
129 <para>
130 The Linux kernel provides more basic utility functions.
131 </para>
132
133 <sect1><title>Bitmap Operations</title>
134!Elib/bitmap.c
135!Ilib/bitmap.c
136 </sect1>
137
138 <sect1><title>Command-line Parsing</title>
139!Elib/cmdline.c
140 </sect1>
141
142 <sect1 id="crc"><title>CRC Functions</title>
143!Elib/crc7.c
144!Elib/crc16.c
145!Elib/crc-itu-t.c
146!Elib/crc32.c
147!Elib/crc-ccitt.c
148 </sect1>
149 </chapter>
150
151 <chapter id="mm">
152 <title>Memory Management in Linux</title>
153 <sect1><title>The Slab Cache</title>
154!Iinclude/linux/slab.h
155!Emm/slab.c
156 </sect1>
157 <sect1><title>User Space Memory Access</title>
158!Iinclude/asm-i386/uaccess.h
159!Earch/i386/lib/usercopy.c
160 </sect1>
161 <sect1><title>More Memory Management Functions</title>
162!Emm/readahead.c
163!Emm/filemap.c
164!Emm/memory.c
165!Emm/vmalloc.c
166!Imm/page_alloc.c
167!Emm/mempool.c
168!Emm/page-writeback.c
169!Emm/truncate.c
170 </sect1>
171 </chapter>
172
173
174 <chapter id="ipc">
175 <title>Kernel IPC facilities</title>
176
177 <sect1><title>IPC utilities</title>
178!Iipc/util.c
179 </sect1>
180 </chapter>
181
182 <chapter id="kfifo">
183 <title>FIFO Buffer</title>
184 <sect1><title>kfifo interface</title>
185!Iinclude/linux/kfifo.h
186!Ekernel/kfifo.c
187 </sect1>
188 </chapter>
189
190 <chapter id="relayfs">
191 <title>relay interface support</title>
192
193 <para>
194 Relay interface support
195 is designed to provide an efficient mechanism for tools and
196 facilities to relay large amounts of data from kernel space to
197 user space.
198 </para>
199
200 <sect1><title>relay interface</title>
201!Ekernel/relay.c
202!Ikernel/relay.c
203 </sect1>
204 </chapter>
205
206 <chapter id="netcore">
207 <title>Linux Networking</title>
208 <sect1><title>Networking Base Types</title>
209!Iinclude/linux/net.h
210 </sect1>
211 <sect1><title>Socket Buffer Functions</title>
212!Iinclude/linux/skbuff.h
213!Iinclude/net/sock.h
214!Enet/socket.c
215!Enet/core/skbuff.c
216!Enet/core/sock.c
217!Enet/core/datagram.c
218!Enet/core/stream.c
219 </sect1>
220 <sect1><title>Socket Filter</title>
221!Enet/core/filter.c
222 </sect1>
223 <sect1><title>Generic Network Statistics</title>
224!Iinclude/linux/gen_stats.h
225!Enet/core/gen_stats.c
226!Enet/core/gen_estimator.c
227 </sect1>
228 <sect1><title>SUN RPC subsystem</title>
229<!-- The !D functionality is not perfect, garbage has to be protected by comments
230!Dnet/sunrpc/sunrpc_syms.c
231-->
232!Enet/sunrpc/xdr.c
233!Enet/sunrpc/svcsock.c
234!Enet/sunrpc/sched.c
235 </sect1>
236 </chapter>
237
238 <chapter id="netdev">
239 <title>Network device support</title>
240 <sect1><title>Driver Support</title>
241!Enet/core/dev.c
242!Enet/ethernet/eth.c
243!Iinclude/linux/etherdevice.h
244!Edrivers/net/phy/phy.c
245!Idrivers/net/phy/phy.c
246!Edrivers/net/phy/phy_device.c
247!Idrivers/net/phy/phy_device.c
248!Edrivers/net/phy/mdio_bus.c
249!Idrivers/net/phy/mdio_bus.c
250<!-- FIXME: Removed for now since no structured comments in source
251X!Enet/core/wireless.c
252-->
253 </sect1>
254 <sect1><title>Synchronous PPP</title>
255!Edrivers/net/wan/syncppp.c
256 </sect1>
257 </chapter>
258
259 <chapter id="modload">
260 <title>Module Support</title>
261 <sect1><title>Module Loading</title>
262!Ekernel/kmod.c
263 </sect1>
264 <sect1><title>Inter Module support</title>
265 <para>
266 Refer to the file kernel/module.c for more information.
267 </para>
268<!-- FIXME: Removed for now since no structured comments in source
269X!Ekernel/module.c
270-->
271 </sect1>
272 </chapter>
273
274 <chapter id="hardware">
275 <title>Hardware Interfaces</title>
276 <sect1><title>Interrupt Handling</title>
277!Ekernel/irq/manage.c
278 </sect1>
279
280 <sect1><title>DMA Channels</title>
281!Ekernel/dma.c
282 </sect1>
283
284 <sect1><title>Resources Management</title>
285!Ikernel/resource.c
286!Ekernel/resource.c
287 </sect1>
288
289 <sect1><title>MTRR Handling</title>
290!Earch/i386/kernel/cpu/mtrr/main.c
291 </sect1>
292
293 <sect1><title>PCI Support Library</title>
294!Edrivers/pci/pci.c
295!Edrivers/pci/pci-driver.c
296!Edrivers/pci/remove.c
297!Edrivers/pci/pci-acpi.c
298!Edrivers/pci/search.c
299!Edrivers/pci/msi.c
300!Edrivers/pci/bus.c
301<!-- FIXME: Removed for now since no structured comments in source
302X!Edrivers/pci/hotplug.c
303-->
304!Edrivers/pci/probe.c
305!Edrivers/pci/rom.c
306 </sect1>
307 <sect1><title>PCI Hotplug Support Library</title>
308!Edrivers/pci/hotplug/pci_hotplug_core.c
309 </sect1>
310 <sect1><title>MCA Architecture</title>
311 <sect2><title>MCA Device Functions</title>
312 <para>
313 Refer to the file arch/i386/kernel/mca.c for more information.
314 </para>
315<!-- FIXME: Removed for now since no structured comments in source
316X!Earch/i386/kernel/mca.c
317-->
318 </sect2>
319 <sect2><title>MCA Bus DMA</title>
320!Iinclude/asm-i386/mca_dma.h
321 </sect2>
322 </sect1>
323 </chapter>
324
325 <chapter id="firmware">
326 <title>Firmware Interfaces</title>
327 <sect1><title>DMI Interfaces</title>
328!Edrivers/firmware/dmi_scan.c
329 </sect1>
330 <sect1><title>EDD Interfaces</title>
331!Idrivers/firmware/edd.c
332 </sect1>
333 </chapter>
334
335 <chapter id="security">
336 <title>Security Framework</title>
337!Esecurity/security.c
338 </chapter>
339
340 <chapter id="audit">
341 <title>Audit Interfaces</title>
342!Ekernel/audit.c
343!Ikernel/auditsc.c
344!Ikernel/auditfilter.c
345 </chapter>
346
347 <chapter id="accounting">
348 <title>Accounting Framework</title>
349!Ikernel/acct.c
350 </chapter>
351
352 <chapter id="pmfuncs">
353 <title>Power Management</title>
354!Ekernel/power/pm.c
355 </chapter>
356
357 <chapter id="devdrivers">
358 <title>Device drivers infrastructure</title>
359 <sect1><title>Device Drivers Base</title>
360<!--
361X!Iinclude/linux/device.h
362-->
363!Edrivers/base/driver.c
364!Edrivers/base/core.c
365!Edrivers/base/class.c
366!Edrivers/base/firmware_class.c
367!Edrivers/base/transport_class.c
368!Edrivers/base/dmapool.c
369<!-- Cannot be included, because
370 attribute_container_add_class_device_adapter
371 and attribute_container_classdev_to_container
372 exceed allowed 44 characters maximum
373X!Edrivers/base/attribute_container.c
374-->
375!Edrivers/base/sys.c
376<!--
377X!Edrivers/base/interface.c
378-->
379!Edrivers/base/platform.c
380!Edrivers/base/bus.c
381 </sect1>
382 <sect1><title>Device Drivers Power Management</title>
383!Edrivers/base/power/resume.c
384!Edrivers/base/power/suspend.c
385 </sect1>
386 <sect1><title>Device Drivers ACPI Support</title>
387<!-- Internal functions only
388X!Edrivers/acpi/sleep/main.c
389X!Edrivers/acpi/sleep/wakeup.c
390X!Edrivers/acpi/motherboard.c
391X!Edrivers/acpi/bus.c
392-->
393!Edrivers/acpi/scan.c
394!Idrivers/acpi/scan.c
395<!-- No correct structured comments
396X!Edrivers/acpi/pci_bind.c
397-->
398 </sect1>
399 <sect1><title>Device drivers PnP support</title>
400!Idrivers/pnp/core.c
401<!-- No correct structured comments
402X!Edrivers/pnp/system.c
403 -->
404!Edrivers/pnp/card.c
405!Idrivers/pnp/driver.c
406!Edrivers/pnp/manager.c
407!Edrivers/pnp/support.c
408 </sect1>
409 <sect1><title>Userspace IO devices</title>
410!Edrivers/uio/uio.c
411!Iinclude/linux/uio_driver.h
412 </sect1>
413 </chapter>
414
415 <chapter id="blkdev">
416 <title>Block Devices</title>
417!Eblock/ll_rw_blk.c
418 </chapter>
419
420 <chapter id="chrdev">
421 <title>Char devices</title>
422!Efs/char_dev.c
423 </chapter>
424
425 <chapter id="miscdev">
426 <title>Miscellaneous Devices</title>
427!Edrivers/char/misc.c
428 </chapter>
429
430 <chapter id="parportdev">
431 <title>Parallel Port Devices</title>
432!Iinclude/linux/parport.h
433!Edrivers/parport/ieee1284.c
434!Edrivers/parport/share.c
435!Idrivers/parport/daisy.c
436 </chapter>
437
438 <chapter id="message_devices">
439 <title>Message-based devices</title>
440 <sect1><title>Fusion message devices</title>
441!Edrivers/message/fusion/mptbase.c
442!Idrivers/message/fusion/mptbase.c
443!Edrivers/message/fusion/mptscsih.c
444!Idrivers/message/fusion/mptscsih.c
445!Idrivers/message/fusion/mptctl.c
446!Idrivers/message/fusion/mptspi.c
447!Idrivers/message/fusion/mptfc.c
448!Idrivers/message/fusion/mptlan.c
449 </sect1>
450 <sect1><title>I2O message devices</title>
451!Iinclude/linux/i2o.h
452!Idrivers/message/i2o/core.h
453!Edrivers/message/i2o/iop.c
454!Idrivers/message/i2o/iop.c
455!Idrivers/message/i2o/config-osm.c
456!Edrivers/message/i2o/exec-osm.c
457!Idrivers/message/i2o/exec-osm.c
458!Idrivers/message/i2o/bus-osm.c
459!Edrivers/message/i2o/device.c
460!Idrivers/message/i2o/device.c
461!Idrivers/message/i2o/driver.c
462!Idrivers/message/i2o/pci.c
463!Idrivers/message/i2o/i2o_block.c
464!Idrivers/message/i2o/i2o_scsi.c
465!Idrivers/message/i2o/i2o_proc.c
466 </sect1>
467 </chapter>
468
469 <chapter id="snddev">
470 <title>Sound Devices</title>
471!Iinclude/sound/core.h
472!Esound/sound_core.c
473!Iinclude/sound/pcm.h
474!Esound/core/pcm.c
475!Esound/core/device.c
476!Esound/core/info.c
477!Esound/core/rawmidi.c
478!Esound/core/sound.c
479!Esound/core/memory.c
480!Esound/core/pcm_memory.c
481!Esound/core/init.c
482!Esound/core/isadma.c
483!Esound/core/control.c
484!Esound/core/pcm_lib.c
485!Esound/core/hwdep.c
486!Esound/core/pcm_native.c
487!Esound/core/memalloc.c
488<!-- FIXME: Removed for now since no structured comments in source
489X!Isound/sound_firmware.c
490-->
491 </chapter>
492
493 <chapter id="uart16x50">
494 <title>16x50 UART Driver</title>
495!Iinclude/linux/serial_core.h
496!Edrivers/serial/serial_core.c
497!Edrivers/serial/8250.c
498 </chapter>
499
500 <chapter id="z85230">
501 <title>Z85230 Support Library</title>
502!Edrivers/net/wan/z85230.c
503 </chapter>
504
505 <chapter id="fbdev">
506 <title>Frame Buffer Library</title>
507
508 <para>
509 The frame buffer drivers depend heavily on four data structures.
510 These structures are declared in include/linux/fb.h. They are
511 fb_info, fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs.
512 The last three can be made available to and from userland.
513 </para>
514
515 <para>
516 fb_info defines the current state of a particular video card.
517 Inside fb_info, there exists a fb_ops structure which is a
518 collection of needed functions to make fbdev and fbcon work.
519 fb_info is only visible to the kernel.
520 </para>
521
522 <para>
523 fb_var_screeninfo is used to describe the features of a video card
524 that are user defined. With fb_var_screeninfo, things such as
525 depth and the resolution may be defined.
526 </para>
527
528 <para>
529 The next structure is fb_fix_screeninfo. This defines the
530 properties of a card that are created when a mode is set and can't
531 be changed otherwise. A good example of this is the start of the
532 frame buffer memory. This "locks" the address of the frame buffer
533 memory, so that it cannot be changed or moved.
534 </para>
535
536 <para>
537 The last structure is fb_monospecs. In the old API, there was
538 little importance for fb_monospecs. This allowed for forbidden things
539 such as setting a mode of 800x600 on a fix frequency monitor. With
540 the new API, fb_monospecs prevents such things, and if used
541 correctly, can prevent a monitor from being cooked. fb_monospecs
542 will not be useful until kernels 2.5.x.
543 </para>
544
545 <sect1><title>Frame Buffer Memory</title>
546!Edrivers/video/fbmem.c
547 </sect1>
548<!--
549 <sect1><title>Frame Buffer Console</title>
550X!Edrivers/video/console/fbcon.c
551 </sect1>
552-->
553 <sect1><title>Frame Buffer Colormap</title>
554!Edrivers/video/fbcmap.c
555 </sect1>
556<!-- FIXME:
557 drivers/video/fbgen.c has no docs, which stuffs up the sgml. Comment
558 out until somebody adds docs. KAO
559 <sect1><title>Frame Buffer Generic Functions</title>
560X!Idrivers/video/fbgen.c
561 </sect1>
562KAO -->
563 <sect1><title>Frame Buffer Video Mode Database</title>
564!Idrivers/video/modedb.c
565!Edrivers/video/modedb.c
566 </sect1>
567 <sect1><title>Frame Buffer Macintosh Video Mode Database</title>
568!Edrivers/video/macmodes.c
569 </sect1>
570 <sect1><title>Frame Buffer Fonts</title>
571 <para>
572 Refer to the file drivers/video/console/fonts.c for more information.
573 </para>
574<!-- FIXME: Removed for now since no structured comments in source
575X!Idrivers/video/console/fonts.c
576-->
577 </sect1>
578 </chapter>
579
580 <chapter id="input_subsystem">
581 <title>Input Subsystem</title>
582!Iinclude/linux/input.h
583!Edrivers/input/input.c
584!Edrivers/input/ff-core.c
585!Edrivers/input/ff-memless.c
586 </chapter>
587
588 <chapter id="spi">
589 <title>Serial Peripheral Interface (SPI)</title>
590 <para>
591 SPI is the "Serial Peripheral Interface", widely used with
592 embedded systems because it is a simple and efficient
593 interface: basically a multiplexed shift register.
594 Its three signal wires hold a clock (SCK, often in the range
595 of 1-20 MHz), a "Master Out, Slave In" (MOSI) data line, and
596 a "Master In, Slave Out" (MISO) data line.
597 SPI is a full duplex protocol; for each bit shifted out the
598 MOSI line (one per clock) another is shifted in on the MISO line.
599 Those bits are assembled into words of various sizes on the
600 way to and from system memory.
601 An additional chipselect line is usually active-low (nCS);
602 four signals are normally used for each peripheral, plus
603 sometimes an interrupt.
604 </para>
605 <para>
606 The SPI bus facilities listed here provide a generalized
607 interface to declare SPI busses and devices, manage them
608 according to the standard Linux driver model, and perform
609 input/output operations.
610 At this time, only "master" side interfaces are supported,
611 where Linux talks to SPI peripherals and does not implement
612 such a peripheral itself.
613 (Interfaces to support implementing SPI slaves would
614 necessarily look different.)
615 </para>
616 <para>
617 The programming interface is structured around two kinds of driver,
618 and two kinds of device.
619 A "Controller Driver" abstracts the controller hardware, which may
620 be as simple as a set of GPIO pins or as complex as a pair of FIFOs
621 connected to dual DMA engines on the other side of the SPI shift
622 register (maximizing throughput). Such drivers bridge between
623 whatever bus they sit on (often the platform bus) and SPI, and
624 expose the SPI side of their device as a
625 <structname>struct spi_master</structname>.
626 SPI devices are children of that master, represented as a
627 <structname>struct spi_device</structname> and manufactured from
628 <structname>struct spi_board_info</structname> descriptors which
629 are usually provided by board-specific initialization code.
630 A <structname>struct spi_driver</structname> is called a
631 "Protocol Driver", and is bound to a spi_device using normal
632 driver model calls.
633 </para>
634 <para>
635 The I/O model is a set of queued messages. Protocol drivers
636 submit one or more <structname>struct spi_message</structname>
637 objects, which are processed and completed asynchronously.
638 (There are synchronous wrappers, however.) Messages are
639 built from one or more <structname>struct spi_transfer</structname>
640 objects, each of which wraps a full duplex SPI transfer.
641 A variety of protocol tweaking options are needed, because
642 different chips adopt very different policies for how they
643 use the bits transferred with SPI.
644 </para>
645!Iinclude/linux/spi/spi.h
646!Fdrivers/spi/spi.c spi_register_board_info
647!Edrivers/spi/spi.c
648 </chapter>
649
650 <chapter id="i2c">
651 <title>I<superscript>2</superscript>C and SMBus Subsystem</title>
652
653 <para>
654 I<superscript>2</superscript>C (or without fancy typography, "I2C")
655 is an acronym for the "Inter-IC" bus, a simple bus protocol which is
656 widely used where low data rate communications suffice.
657 Since it's also a licensed trademark, some vendors use another
658 name (such as "Two-Wire Interface", TWI) for the same bus.
659 I2C only needs two signals (SCL for clock, SDA for data), conserving
660 board real estate and minimizing signal quality issues.
661 Most I2C devices use seven bit addresses, and bus speeds of up
662 to 400 kHz; there's a high speed extension (3.4 MHz) that's not yet
663 found wide use.
664 I2C is a multi-master bus; open drain signaling is used to
665 arbitrate between masters, as well as to handshake and to
666 synchronize clocks from slower clients.
667 </para>
668
669 <para>
670 The Linux I2C programming interfaces support only the master
671 side of bus interactions, not the slave side.
672 The programming interface is structured around two kinds of driver,
673 and two kinds of device.
674 An I2C "Adapter Driver" abstracts the controller hardware; it binds
675 to a physical device (perhaps a PCI device or platform_device) and
676 exposes a <structname>struct i2c_adapter</structname> representing
677 each I2C bus segment it manages.
678 On each I2C bus segment will be I2C devices represented by a
679 <structname>struct i2c_client</structname>. Those devices will
680 be bound to a <structname>struct i2c_driver</structname>,
681 which should follow the standard Linux driver model.
682 (At this writing, a legacy model is more widely used.)
683 There are functions to perform various I2C protocol operations; at
684 this writing all such functions are usable only from task context.
685 </para>
686
687 <para>
688 The System Management Bus (SMBus) is a sibling protocol. Most SMBus
689 systems are also I2C conformant. The electrical constraints are
690 tighter for SMBus, and it standardizes particular protocol messages
691 and idioms. Controllers that support I2C can also support most
692 SMBus operations, but SMBus controllers don't support all the protocol
693 options that an I2C controller will.
694 There are functions to perform various SMBus protocol operations,
695 either using I2C primitives or by issuing SMBus commands to
696 i2c_adapter devices which don't support those I2C operations.
697 </para>
698
699!Iinclude/linux/i2c.h
700!Fdrivers/i2c/i2c-boardinfo.c i2c_register_board_info
701!Edrivers/i2c/i2c-core.c
702 </chapter>
703
704 <chapter id="splice">
705 <title>splice API</title>
706 <para>
707 splice is a method for moving blocks of data around inside the
708 kernel, without continually transferring them between the kernel
709 and user space.
710 </para>
711!Ffs/splice.c
712 </chapter>
713
714 <chapter id="pipes">
715 <title>pipes API</title>
716 <para>
717 Pipe interfaces are all for in-kernel (builtin image) use.
718 They are not exported for use by modules.
719 </para>
720!Iinclude/linux/pipe_fs_i.h
721!Ffs/pipe.c
722 </chapter>
723
724</book>