The Linux Kernel API

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Table of Contents

1. Driver Basics
Driver Entry and Exit points
Atomic and pointer manipulation
Delaying, scheduling, and timer routines
High-resolution timers
Workqueues and Kevents
Internal Functions
Kernel objects manipulation
Kernel utility functions
Device Resource Management
2. Data Types
Doubly Linked Lists
3. Basic C Library Functions
String Conversions
String Manipulation
Bit Operations
4. Basic Kernel Library Functions
Bitmap Operations
Command-line Parsing
CRC Functions
5. Memory Management in Linux
The Slab Cache
User Space Memory Access
More Memory Management Functions
6. Kernel IPC facilities
IPC utilities
7. FIFO Buffer
kfifo interface
8. relay interface support
relay interface
9. Module Support
Module Loading
Inter Module support
10. Hardware Interfaces
Interrupt Handling
DMA Channels
Resources Management
MTRR Handling
PCI Support Library
PCI Hotplug Support Library
MCA Architecture
MCA Device Functions
11. Firmware Interfaces
DMI Interfaces
EDD Interfaces
12. Security Framework
security_init — initializes the security framework
security_module_enable — Load given security module on boot ?
register_security — registers a security framework with the kernel
mod_reg_security — allows security modules to be “stacked
13. Audit Interfaces
audit_log_start — obtain an audit buffer
audit_log_format — format a message into the audit buffer.
audit_log_end — end one audit record
audit_log — Log an audit record
audit_alloc — allocate an audit context block for a task
audit_free — free a per-task audit context
audit_syscall_entry — fill in an audit record at syscall entry
audit_syscall_exit — deallocate audit context after a system call
__audit_getname — add a name to the list
__audit_inode — store the inode and device from a lookup
auditsc_get_stamp — get local copies of audit_context values
audit_set_loginuid — set a task's audit_context loginuid
__audit_mq_open — record audit data for a POSIX MQ open
__audit_mq_timedsend — record audit data for a POSIX MQ timed send
__audit_mq_timedreceive — record audit data for a POSIX MQ timed receive
__audit_mq_notify — record audit data for a POSIX MQ notify
__audit_mq_getsetattr — record audit data for a POSIX MQ get/set attribute
__audit_ipc_obj — record audit data for ipc object
__audit_ipc_set_perm — record audit data for new ipc permissions
audit_socketcall — record audit data for sys_socketcall
__audit_fd_pair — record audit data for pipe and socketpair
audit_sockaddr — record audit data for sys_bind, sys_connect, sys_sendto
__audit_signal_info — record signal info for shutting down audit subsystem
audit_core_dumps — record information about processes that end abnormally
audit_receive_filter — apply all rules to the specified message type
14. Accounting Framework
sys_acct — enable/disable process accounting
acct_auto_close_mnt — turn off a filesystem's accounting if it is on
acct_auto_close — turn off a filesystem's accounting if it is on
acct_init_pacct — initialize a new pacct_struct
acct_collect — collect accounting information into pacct_struct
acct_process — now just a wrapper around do_acct_process
15. Device drivers infrastructure
Device Drivers Base
Device Drivers Power Management
Device Drivers ACPI Support
Device drivers PnP support
Userspace IO devices
16. Block Devices
blk_get_backing_dev_info — get the address of a queue's backing_dev_info
generic_unplug_device — fire a request queue
blk_start_queue — restart a previously stopped queue
blk_stop_queue — stop a queue
blk_sync_queue — cancel any pending callbacks on a queue
__blk_run_queue — run a single device queue
blk_run_queue — run a single device queue
blk_init_queue — prepare a request queue for use with a block device
blk_start_queueing — initiate dispatch of requests to device
blk_requeue_request — put a request back on queue
blk_insert_request — insert a special request in to a request queue
blk_complete_request — end I/O on a request
blk_rq_bytes — Returns bytes left to complete in the entire request
blk_rq_cur_bytes — Returns bytes left to complete in the current segment
end_queued_request — end all I/O on a queued request
end_dequeued_request — end all I/O on a dequeued request
end_request — end I/O on the current segment of the request
blk_end_request — Helper function for drivers to complete the request.
__blk_end_request — Helper function for drivers to complete the request.
blk_end_bidi_request — Helper function for drivers to complete bidi request.
blk_end_request_callback — Special helper function for tricky drivers
__end_that_request_first — end I/O on a request
blk_end_io — Generic end_io function to complete a request.
blk_rq_map_user — map user data to a request, for REQ_BLOCK_PC usage
blk_rq_unmap_user — unmap a request with user data
blk_rq_map_kern — map kernel data to a request, for REQ_BLOCK_PC usage
blk_release_queue — release a struct request_queue when it is no longer needed
blk_queue_prep_rq — set a prepare_request function for queue
blk_queue_merge_bvec — set a merge_bvec function for queue
blk_queue_make_request — define an alternate make_request function for a device
blk_queue_bounce_limit — set bounce buffer limit for queue
blk_queue_max_sectors — set max sectors for a request for this queue
blk_queue_max_phys_segments — set max phys segments for a request for this queue
blk_queue_max_hw_segments — set max hw segments for a request for this queue
blk_queue_max_segment_size — set max segment size for blk_rq_map_sg
blk_queue_hardsect_size — set hardware sector size for the queue
blk_queue_stack_limits — inherit underlying queue limits for stacked drivers
blk_queue_dma_pad — set pad mask
blk_queue_dma_drain — Set up a drain buffer for excess dma.
blk_queue_segment_boundary — set boundary rules for segment merging
blk_queue_dma_alignment — set dma length and memory alignment
blk_queue_update_dma_alignment — update dma length and memory alignment
blk_end_sync_rq — executes a completion event on a request
blk_execute_rq_nowait — insert a request into queue for execution
blk_execute_rq — insert a request into queue for execution
blk_queue_ordered — does this queue support ordered writes
blkdev_issue_flush — queue a flush
blk_queue_find_tag — find a request by its tag and queue
blk_free_tags — release a given set of tag maintenance info
blk_queue_free_tags — release tag maintenance info
blk_init_tags — initialize the tag info for an external tag map
blk_queue_init_tags — initialize the queue tag info
blk_queue_resize_tags — change the queueing depth
blk_queue_end_tag — end tag operations for a request
blk_queue_start_tag — find a free tag and assign it
blk_queue_invalidate_tags — invalidate all pending tags
__blk_free_tags — release a given set of tag maintenance info
__blk_queue_free_tags — release tag maintenance info
17. Char devices
register_chrdev_region — register a range of device numbers
alloc_chrdev_region — register a range of char device numbers
register_chrdev — Register a major number for character devices.
unregister_chrdev_region — return a range of device numbers
cdev_add — add a char device to the system
cdev_del — remove a cdev from the system
cdev_alloc — allocate a cdev structure
cdev_init — initialize a cdev structure
18. Miscellaneous Devices
misc_register — register a miscellaneous device
misc_deregister — unregister a miscellaneous device
19. Parallel Port Devices
parport_yield — relinquish a parallel port temporarily
parport_yield_blocking — relinquish a parallel port temporarily
parport_wait_event — wait for an event on a parallel port
parport_wait_peripheral — wait for status lines to change in 35ms
parport_negotiate — negotiate an IEEE 1284 mode
parport_write — write a block of data to a parallel port
parport_read — read a block of data from a parallel port
parport_set_timeout — set the inactivity timeout for a device
parport_register_driver — register a parallel port device driver
parport_unregister_driver — deregister a parallel port device driver
parport_get_port — increment a port's reference count
parport_put_port — decrement a port's reference count
parport_register_port — register a parallel port
parport_announce_port — tell device drivers about a parallel port
parport_remove_port — deregister a parallel port
parport_register_device — register a device on a parallel port
parport_unregister_device — deregister a device on a parallel port
parport_find_number — find a parallel port by number
parport_find_base — find a parallel port by base address
parport_claim — claim access to a parallel port device
parport_claim_or_block — claim access to a parallel port device
parport_release — give up access to a parallel port device
parport_open — find a device by canonical device number
parport_close — close a device opened with parport_open
20. Message-based devices
Fusion message devices
I2O message devices
21. Sound Devices
snd_register_device — Register the ALSA device file for the card
snd_printk — printk wrapper
snd_printd — debug printk
snd_assert — run-time assertion macro
snd_printdd — debug printk
register_sound_special_device — register a special sound node
register_sound_mixer — register a mixer device
register_sound_midi — register a midi device
register_sound_dsp — register a DSP device
unregister_sound_special — unregister a special sound device
unregister_sound_mixer — unregister a mixer
unregister_sound_midi — unregister a midi device
unregister_sound_dsp — unregister a DSP device
snd_pcm_playback_ready — check whether the playback buffer is available
snd_pcm_capture_ready — check whether the capture buffer is available
snd_pcm_playback_data — check whether any data exists on the playback buffer
snd_pcm_playback_empty — check whether the playback buffer is empty
snd_pcm_capture_empty — check whether the capture buffer is empty
snd_pcm_format_cpu_endian — Check the PCM format is CPU-endian
snd_pcm_new_stream — create a new PCM stream
snd_pcm_new — create a new PCM instance
snd_device_new — create an ALSA device component
snd_device_free — release the device from the card
snd_device_register — register the device
snd_iprintf — printf on the procfs buffer
snd_info_get_line — read one line from the procfs buffer
snd_info_get_str — parse a string token
snd_info_create_module_entry — create an info entry for the given module
snd_info_create_card_entry — create an info entry for the given card
snd_card_proc_new — create an info entry for the given card
snd_info_free_entry — release the info entry
snd_info_register — register the info entry
snd_rawmidi_receive — receive the input data from the device
snd_rawmidi_transmit_empty — check whether the output buffer is empty
snd_rawmidi_transmit_peek — copy data from the internal buffer
snd_rawmidi_transmit_ack — acknowledge the transmission
snd_rawmidi_transmit — copy from the buffer to the device
snd_rawmidi_new — create a rawmidi instance
snd_rawmidi_set_ops — set the rawmidi operators
snd_request_card — try to load the card module
snd_lookup_minor_data — get user data of a registered device
snd_register_device_for_dev — Register the ALSA device file for the card
snd_unregister_device — unregister the device on the given card
copy_to_user_fromio — copy data from mmio-space to user-space
copy_from_user_toio — copy data from user-space to mmio-space
snd_pcm_lib_preallocate_free_for_all — release all pre-allocated buffers on the pcm
snd_pcm_lib_preallocate_pages — pre-allocation for the given DMA type
snd_pcm_lib_preallocate_pages_for_all — pre-allocation for continous memory type (all substreams)
snd_pcm_sgbuf_ops_page — get the page struct at the given offset
snd_pcm_lib_malloc_pages — allocate the DMA buffer
snd_pcm_lib_free_pages — release the allocated DMA buffer.
snd_card_new — create and initialize a soundcard structure
snd_card_disconnect — disconnect all APIs from the file-operations (user space)
snd_card_register — register the soundcard
snd_component_add — add a component string
snd_card_file_add — add the file to the file list of the card
snd_card_file_remove — remove the file from the file list
snd_power_wait — wait until the power-state is changed.
snd_dma_program — program an ISA DMA transfer
snd_dma_disable — stop the ISA DMA transfer
snd_dma_pointer — return the current pointer to DMA transfer buffer in bytes
snd_ctl_new1 — create a control instance from the template
snd_ctl_free_one — release the control instance
snd_ctl_add — add the control instance to the card
snd_ctl_remove — remove the control from the card and release it
snd_ctl_remove_id — remove the control of the given id and release it
snd_ctl_rename_id — replace the id of a control on the card
snd_ctl_find_numid — find the control instance with the given number-id
snd_ctl_find_id — find the control instance with the given id
snd_pcm_set_ops — set the PCM operators
snd_pcm_set_sync — set the PCM sync id
snd_interval_refine — refine the interval value of configurator
snd_interval_ratnum — refine the interval value
snd_interval_list — refine the interval value from the list
snd_pcm_hw_rule_add — add the hw-constraint rule
snd_pcm_lib_ioctl — a generic PCM ioctl callback
snd_pcm_period_elapsed — update the pcm status for the next period
snd_hwdep_new — create a new hwdep instance
snd_malloc_pages — allocate pages with the given size
snd_free_pages — release the pages
snd_dma_alloc_pages — allocate the buffer area according to the given type
snd_dma_alloc_pages_fallback — allocate the buffer area according to the given type with fallback
snd_dma_free_pages — release the allocated buffer
snd_dma_get_reserved_buf — get the reserved buffer for the given device
snd_dma_reserve_buf — reserve the buffer
22. 16x50 UART Driver
uart_handle_dcd_change — handle a change of carrier detect state
uart_handle_cts_change — handle a change of clear-to-send state
uart_update_timeout — update per-port FIFO timeout.
uart_get_baud_rate — return baud rate for a particular port
uart_get_divisor — return uart clock divisor
uart_parse_options — Parse serial port baud/parity/bits/flow contro.
uart_set_options — setup the serial console parameters
uart_register_driver — register a driver with the uart core layer
uart_unregister_driver — remove a driver from the uart core layer
uart_add_one_port — attach a driver-defined port structure
uart_remove_one_port — detach a driver defined port structure
serial8250_suspend_port — suspend one serial port
serial8250_resume_port — resume one serial port
serial8250_register_port — register a serial port
serial8250_unregister_port — remove a 16x50 serial port at runtime
23. Frame Buffer Library
Frame Buffer Memory
Frame Buffer Colormap
Frame Buffer Video Mode Database
Frame Buffer Macintosh Video Mode Database
Frame Buffer Fonts
24. Input Subsystem
struct ff_replay — defines scheduling of the force-feedback effect
struct ff_trigger — defines what triggers the force-feedback effect
struct ff_envelope — generic force-feedback effect envelope
struct ff_constant_effect — defines parameters of a constant force-feedback effect
struct ff_ramp_effect — defines parameters of a ramp force-feedback effect
struct ff_condition_effect — defines a spring or friction force-feedback effect
struct ff_periodic_effect — defines parameters of a periodic force-feedback effect
struct ff_rumble_effect — defines parameters of a periodic force-feedback effect
struct ff_effect — defines force feedback effect
struct input_dev — represents an input device
struct input_handler — implements one of interfaces for input devices
struct input_handle — links input device with an input handler
struct ff_device — force-feedback part of an input device
input_event — report new input event
input_inject_event — send input event from input handler
input_grab_device — grabs device for exclusive use
input_release_device — release previously grabbed device
input_open_device — open input device
input_close_device — close input device
input_get_keycode — retrieve keycode currently mapped to a given scancode
input_set_keycode — assign new keycode to a given scancode
input_allocate_device — allocate memory for new input device
input_free_device — free memory occupied by input_dev structure
input_set_capability — mark device as capable of a certain event
input_register_device — register device with input core
input_unregister_device — unregister previously registered device
input_register_handler — register a new input handler
input_unregister_handler — unregisters an input handler
input_register_handle — register a new input handle
input_unregister_handle — unregister an input handle
input_ff_upload — upload effect into force-feedback device
input_ff_erase — erase a force-feedback effect from device
input_ff_event — generic handler for force-feedback events
input_ff_create — create force-feedback device
input_ff_destroy — frees force feedback portion of input device
input_ff_create_memless — create memoryless force-feedback device
25. Serial Peripheral Interface (SPI)
struct spi_device — Master side proxy for an SPI slave device
struct spi_driver — Host side “protocol” driver
spi_unregister_driver — reverse effect of spi_register_driver
struct spi_master — interface to SPI master controller
struct spi_transfer — a read/write buffer pair
struct spi_message — one multi-segment SPI transaction
spi_setup — setup SPI mode and clock rate
spi_async — asynchronous SPI transfer
spi_write — SPI synchronous write
spi_read — SPI synchronous read
spi_w8r8 — SPI synchronous 8 bit write followed by 8 bit read
spi_w8r16 — SPI synchronous 8 bit write followed by 16 bit read
struct spi_board_info — board-specific template for a SPI device
spi_register_board_info — register SPI devices for a given board
spi_register_driver — register a SPI driver
spi_new_device — instantiate one new SPI device
spi_alloc_master — allocate SPI master controller
spi_register_master — register SPI master controller
spi_unregister_master — unregister SPI master controller
spi_busnum_to_master — look up master associated with bus_num
spi_sync — blocking/synchronous SPI data transfers
spi_write_then_read — SPI synchronous write followed by read
26. I2C and SMBus Subsystem
struct i2c_client — represent an I2C slave device
struct i2c_board_info — template for device creation
I2C_BOARD_INFO — macro used to list an i2c device and its address
struct i2c_msg — an I2C transaction segment beginning with START
i2c_register_board_info — statically declare I2C devices
i2c_verify_client — return parameter as i2c_client, or NULL
i2c_new_device — instantiate an i2c device for use with a new style driver
i2c_unregister_device — reverse effect of i2c_new_device
i2c_new_dummy — return a new i2c device bound to a dummy driver
i2c_add_adapter — declare i2c adapter, use dynamic bus number
i2c_add_numbered_adapter — declare i2c adapter, use static bus number
i2c_del_adapter — unregister I2C adapter
i2c_del_driver — unregister I2C driver
i2c_use_client — increments the reference count of the i2c client structure
i2c_release_client — release a use of the i2c client structure
i2c_smbus_read_block_data — SMBus block read request
27. Clock Framework
clk_get — lookup and obtain a reference to a clock producer.
clk_enable — inform the system when the clock source should be running.
clk_disable — inform the system when the clock source is no longer required.
clk_get_rate — obtain the current clock rate (in Hz) for a clock source.
clk_put — "free" the clock source
clk_round_rate — adjust a rate to the exact rate a clock can provide
clk_set_rate — set the clock rate for a clock source
clk_set_parent — set the parent clock source for this clock
clk_get_parent — get the parent clock source for this clock