390 lines
7.9 KiB
ReStructuredText
390 lines
7.9 KiB
ReStructuredText
====================
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The Linux Kernel API
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====================
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List Management Functions
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=========================
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.. kernel-doc:: include/linux/list.h
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:internal:
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Basic C Library Functions
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=========================
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When writing drivers, you cannot in general use routines which are from
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the C Library. Some of the functions have been found generally useful
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and they are listed below. The behaviour of these functions may vary
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slightly from those defined by ANSI, and these deviations are noted in
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the text.
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String Conversions
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------------------
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.. kernel-doc:: lib/vsprintf.c
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:export:
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.. kernel-doc:: include/linux/kernel.h
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:functions: kstrtol
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.. kernel-doc:: include/linux/kernel.h
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:functions: kstrtoul
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.. kernel-doc:: lib/kstrtox.c
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:export:
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String Manipulation
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-------------------
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.. kernel-doc:: lib/string.c
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:export:
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.. kernel-doc:: mm/util.c
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:functions: kstrdup kstrdup_const kstrndup kmemdup kmemdup_nul memdup_user
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vmemdup_user strndup_user memdup_user_nul
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Basic Kernel Library Functions
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==============================
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The Linux kernel provides more basic utility functions.
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Bit Operations
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--------------
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.. kernel-doc:: arch/x86/include/asm/bitops.h
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:internal:
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Bitmap Operations
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-----------------
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.. kernel-doc:: lib/bitmap.c
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:doc: bitmap introduction
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.. kernel-doc:: include/linux/bitmap.h
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:doc: declare bitmap
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.. kernel-doc:: include/linux/bitmap.h
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:doc: bitmap overview
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.. kernel-doc:: include/linux/bitmap.h
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:doc: bitmap bitops
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.. kernel-doc:: lib/bitmap.c
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:export:
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.. kernel-doc:: lib/bitmap.c
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:internal:
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.. kernel-doc:: include/linux/bitmap.h
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:internal:
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Command-line Parsing
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--------------------
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.. kernel-doc:: lib/cmdline.c
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:export:
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Sorting
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-------
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.. kernel-doc:: lib/sort.c
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:export:
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.. kernel-doc:: lib/list_sort.c
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:export:
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Text Searching
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--------------
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.. kernel-doc:: lib/textsearch.c
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:doc: ts_intro
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.. kernel-doc:: lib/textsearch.c
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:export:
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.. kernel-doc:: include/linux/textsearch.h
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:functions: textsearch_find textsearch_next \
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textsearch_get_pattern textsearch_get_pattern_len
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CRC and Math Functions in Linux
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===============================
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CRC Functions
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-------------
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.. kernel-doc:: lib/crc4.c
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:export:
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.. kernel-doc:: lib/crc7.c
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:export:
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.. kernel-doc:: lib/crc8.c
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:export:
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.. kernel-doc:: lib/crc16.c
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:export:
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.. kernel-doc:: lib/crc32.c
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.. kernel-doc:: lib/crc-ccitt.c
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:export:
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.. kernel-doc:: lib/crc-itu-t.c
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:export:
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Base 2 log and power Functions
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------------------------------
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.. kernel-doc:: include/linux/log2.h
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:internal:
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Division Functions
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------------------
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.. kernel-doc:: include/asm-generic/div64.h
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:functions: do_div
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.. kernel-doc:: include/linux/math64.h
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:internal:
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.. kernel-doc:: lib/div64.c
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:functions: div_s64_rem div64_u64_rem div64_u64 div64_s64
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.. kernel-doc:: lib/gcd.c
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:export:
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UUID/GUID
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---------
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.. kernel-doc:: lib/uuid.c
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:export:
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Kernel IPC facilities
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=====================
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IPC utilities
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-------------
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.. kernel-doc:: ipc/util.c
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:internal:
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FIFO Buffer
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===========
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kfifo interface
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---------------
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.. kernel-doc:: include/linux/kfifo.h
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:internal:
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relay interface support
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=======================
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Relay interface support is designed to provide an efficient mechanism
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for tools and facilities to relay large amounts of data from kernel
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space to user space.
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relay interface
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---------------
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.. kernel-doc:: kernel/relay.c
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:export:
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.. kernel-doc:: kernel/relay.c
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:internal:
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Module Support
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==============
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Module Loading
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--------------
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.. kernel-doc:: kernel/kmod.c
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:export:
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Inter Module support
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--------------------
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Refer to the file kernel/module.c for more information.
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Hardware Interfaces
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===================
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Interrupt Handling
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------------------
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.. kernel-doc:: kernel/irq/manage.c
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:export:
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DMA Channels
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------------
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.. kernel-doc:: kernel/dma.c
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:export:
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Resources Management
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--------------------
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.. kernel-doc:: kernel/resource.c
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:internal:
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.. kernel-doc:: kernel/resource.c
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:export:
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MTRR Handling
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-------------
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.. kernel-doc:: arch/x86/kernel/cpu/mtrr/mtrr.c
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:export:
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Security Framework
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==================
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.. kernel-doc:: security/security.c
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:internal:
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.. kernel-doc:: security/inode.c
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:export:
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Audit Interfaces
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================
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.. kernel-doc:: kernel/audit.c
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:export:
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.. kernel-doc:: kernel/auditsc.c
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:internal:
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.. kernel-doc:: kernel/auditfilter.c
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:internal:
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Accounting Framework
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====================
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.. kernel-doc:: kernel/acct.c
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:internal:
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Block Devices
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=============
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.. kernel-doc:: block/blk-core.c
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:export:
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.. kernel-doc:: block/blk-core.c
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:internal:
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.. kernel-doc:: block/blk-map.c
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:export:
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.. kernel-doc:: block/blk-sysfs.c
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:internal:
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.. kernel-doc:: block/blk-settings.c
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:export:
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.. kernel-doc:: block/blk-exec.c
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:export:
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.. kernel-doc:: block/blk-flush.c
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:export:
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.. kernel-doc:: block/blk-lib.c
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:export:
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.. kernel-doc:: block/blk-tag.c
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:export:
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.. kernel-doc:: block/blk-tag.c
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:internal:
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.. kernel-doc:: block/blk-integrity.c
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:export:
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.. kernel-doc:: kernel/trace/blktrace.c
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:internal:
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.. kernel-doc:: block/genhd.c
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:internal:
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.. kernel-doc:: block/genhd.c
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:export:
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Char devices
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============
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.. kernel-doc:: fs/char_dev.c
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:export:
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Clock Framework
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===============
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The clock framework defines programming interfaces to support software
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management of the system clock tree. This framework is widely used with
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System-On-Chip (SOC) platforms to support power management and various
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devices which may need custom clock rates. Note that these "clocks"
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don't relate to timekeeping or real time clocks (RTCs), each of which
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have separate frameworks. These :c:type:`struct clk <clk>`
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instances may be used to manage for example a 96 MHz signal that is used
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to shift bits into and out of peripherals or busses, or otherwise
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trigger synchronous state machine transitions in system hardware.
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Power management is supported by explicit software clock gating: unused
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clocks are disabled, so the system doesn't waste power changing the
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state of transistors that aren't in active use. On some systems this may
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be backed by hardware clock gating, where clocks are gated without being
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disabled in software. Sections of chips that are powered but not clocked
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may be able to retain their last state. This low power state is often
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called a *retention mode*. This mode still incurs leakage currents,
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especially with finer circuit geometries, but for CMOS circuits power is
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mostly used by clocked state changes.
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Power-aware drivers only enable their clocks when the device they manage
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is in active use. Also, system sleep states often differ according to
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which clock domains are active: while a "standby" state may allow wakeup
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from several active domains, a "mem" (suspend-to-RAM) state may require
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a more wholesale shutdown of clocks derived from higher speed PLLs and
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oscillators, limiting the number of possible wakeup event sources. A
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driver's suspend method may need to be aware of system-specific clock
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constraints on the target sleep state.
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Some platforms support programmable clock generators. These can be used
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by external chips of various kinds, such as other CPUs, multimedia
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codecs, and devices with strict requirements for interface clocking.
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.. kernel-doc:: include/linux/clk.h
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:internal:
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Synchronization Primitives
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==========================
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Read-Copy Update (RCU)
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----------------------
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.. kernel-doc:: include/linux/rcupdate.h
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.. kernel-doc:: include/linux/rcupdate_wait.h
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.. kernel-doc:: include/linux/rcutree.h
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.. kernel-doc:: kernel/rcu/tree.c
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.. kernel-doc:: kernel/rcu/tree_plugin.h
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.. kernel-doc:: kernel/rcu/tree_exp.h
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.. kernel-doc:: kernel/rcu/update.c
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.. kernel-doc:: include/linux/srcu.h
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.. kernel-doc:: kernel/rcu/srcutree.c
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.. kernel-doc:: include/linux/rculist_bl.h
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.. kernel-doc:: include/linux/rculist.h
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.. kernel-doc:: include/linux/rculist_nulls.h
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.. kernel-doc:: include/linux/rcu_sync.h
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.. kernel-doc:: kernel/rcu/sync.c
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