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