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bitmap patches for v6.7 

Hi Linus,
 
 Please pull patches for v6.7.
 
 This request includes "bitmap: cleanup bitmap_*_region() implementation"
 series, and scattered cleanup patches.
 
 Thanks,
         Yury
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Merge tag 'bitmap-for-6.7' of https://github.com/norov/linux

Pull bitmap updates from Yury Norov:
 "This includes the 'bitmap: cleanup bitmap_*_region() implementation'
  series, and scattered cleanup patches"

* tag 'bitmap-for-6.7' of https://github.com/norov/linux:
  buildid: reduce header file dependencies for module
  bitmap: move bitmap_*_region() functions to bitmap.h
  bitmap: drop _reg_op() function
  bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit()
  bitmap: replace _reg_op(REG_OP_RELEASE) with bitmap_clear()
  bitmap: replace _reg_op(REG_OP_ALLOC) with bitmap_set()
  bitmap: fix opencoded bitmap_allocate_region()
  bitmap: add test for bitmap_*_region() functions
  bitmap: align __reg_op() wrappers with modern coding style
  lib/bitmap: split-out string-related operations to a separate files
  bitmap: Remove dead code, i.e. bitmap_copy_le()
  bitmap: Fix a typo ("identify map")
  cpumask: kernel-doc cleanups and additions
This commit is contained in:
Linus Torvalds 2023-11-03 07:08:36 -10:00
parent 8f6f76a6a2 bdcb37a5d8
commit 9a719c2145
10 changed files with 700 additions and 754 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
MAINTAINERS
View File

@ -3539,12 +3539,14 @@ R: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
R: Rasmus Villemoes <linux@rasmusvillemoes.dk>
S: Maintained
F: include/linux/bitfield.h
F: include/linux/bitmap-str.h
F: include/linux/bitmap.h
F: include/linux/bits.h
F: include/linux/cpumask.h
F: include/linux/find.h
F: include/linux/nodemask.h
F: include/vdso/bits.h
F: lib/bitmap-str.c
F: lib/bitmap.c
F: lib/cpumask.c
F: lib/cpumask_kunit.c

16
include/linux/bitmap-str.h Normal file
View File

@ -0,0 +1,16 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_BITMAP_STR_H
#define __LINUX_BITMAP_STR_H
int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, unsigned long *dst, int nbits);
int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp, int nmaskbits);
extern int bitmap_print_bitmask_to_buf(char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count);
extern int bitmap_print_list_to_buf(char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count);
int bitmap_parse(const char *buf, unsigned int buflen, unsigned long *dst, int nbits);
int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits);
int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
unsigned long *dst, int nbits);
#endif /* __LINUX_BITMAP_STR_H */

87
include/linux/bitmap.h
View File

@ -6,10 +6,12 @@
#include <linux/align.h>
#include <linux/bitops.h>
#include <linux/errno.h>
#include <linux/find.h>
#include <linux/limits.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/bitmap-str.h>
struct device;
@ -200,14 +202,6 @@ bitmap_find_next_zero_area(unsigned long *map,
align_mask, 0);
}
int bitmap_parse(const char *buf, unsigned int buflen,
unsigned long *dst, int nbits);
int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
unsigned long *dst, int nbits);
int bitmap_parselist(const char *buf, unsigned long *maskp,
int nmaskbits);
int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
unsigned long *dst, int nbits);
void bitmap_remap(unsigned long *dst, const unsigned long *src,
const unsigned long *old, const unsigned long *new, unsigned int nbits);
int bitmap_bitremap(int oldbit,
@ -216,23 +210,6 @@ void bitmap_onto(unsigned long *dst, const unsigned long *orig,
const unsigned long *relmap, unsigned int bits);
void bitmap_fold(unsigned long *dst, const unsigned long *orig,
unsigned int sz, unsigned int nbits);
int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
#ifdef __BIG_ENDIAN
void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
#else
#define bitmap_copy_le bitmap_copy
#endif
int bitmap_print_to_pagebuf(bool list, char *buf,
const unsigned long *maskp, int nmaskbits);
extern int bitmap_print_bitmask_to_buf(char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count);
extern int bitmap_print_list_to_buf(char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count);
#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
@ -518,6 +495,66 @@ static inline void bitmap_next_set_region(unsigned long *bitmap,
*re = find_next_zero_bit(bitmap, end, *rs + 1);
}
/**
* bitmap_release_region - release allocated bitmap region
* @bitmap: array of unsigned longs corresponding to the bitmap
* @pos: beginning of bit region to release
* @order: region size (log base 2 of number of bits) to release
*
* This is the complement to __bitmap_find_free_region() and releases
* the found region (by clearing it in the bitmap).
*/
static inline void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order)
{
bitmap_clear(bitmap, pos, BIT(order));
}
/**
* bitmap_allocate_region - allocate bitmap region
* @bitmap: array of unsigned longs corresponding to the bitmap
* @pos: beginning of bit region to allocate
* @order: region size (log base 2 of number of bits) to allocate
*
* Allocate (set bits in) a specified region of a bitmap.
*
* Returns: 0 on success, or %-EBUSY if specified region wasn't
* free (not all bits were zero).
*/
static inline int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
{
unsigned int len = BIT(order);
if (find_next_bit(bitmap, pos + len, pos) < pos + len)
return -EBUSY;
bitmap_set(bitmap, pos, len);
return 0;
}
/**
* bitmap_find_free_region - find a contiguous aligned mem region
* @bitmap: array of unsigned longs corresponding to the bitmap
* @bits: number of bits in the bitmap
* @order: region size (log base 2 of number of bits) to find
*
* Find a region of free (zero) bits in a @bitmap of @bits bits and
* allocate them (set them to one). Only consider regions of length
* a power (@order) of two, aligned to that power of two, which
* makes the search algorithm much faster.
*
* Returns: the bit offset in bitmap of the allocated region,
* or -errno on failure.
*/
static inline int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order)
{
unsigned int pos, end; /* scans bitmap by regions of size order */
for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) {
if (!bitmap_allocate_region(bitmap, pos, order))
return pos;
}
return -ENOMEM;
}
/**
* BITMAP_FROM_U64() - Represent u64 value in the format suitable for bitmap.
* @n: u64 value

3
include/linux/buildid.h
View File

@ -2,10 +2,11 @@
#ifndef _LINUX_BUILDID_H
#define _LINUX_BUILDID_H
#include <linux/mm_types.h>
#include <linux/types.h>
#define BUILD_ID_SIZE_MAX 20
struct vm_area_struct;
int build_id_parse(struct vm_area_struct *vma, unsigned char *build_id,
__u32 *size);
int build_id_parse_buf(const void *buf, unsigned char *build_id, u32 buf_size);

113
include/linux/cpumask.h
View File

@ -4,7 +4,7 @@
/*
* Cpumasks provide a bitmap suitable for representing the
* set of CPU's in a system, one bit position per CPU number. In general,
* set of CPUs in a system, one bit position per CPU number. In general,
* only nr_cpu_ids (<= NR_CPUS) bits are valid.
*/
#include <linux/kernel.h>
@ -97,7 +97,7 @@ static inline void set_nr_cpu_ids(unsigned int nr)
*
* If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
*
* The cpu_possible_mask is fixed at boot time, as the set of CPU id's
* The cpu_possible_mask is fixed at boot time, as the set of CPU IDs
* that it is possible might ever be plugged in at anytime during the
* life of that system boot. The cpu_present_mask is dynamic(*),
* representing which CPUs are currently plugged in. And
@ -112,7 +112,7 @@ static inline void set_nr_cpu_ids(unsigned int nr)
* hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
*
* Subtleties:
* 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
* 1) UP ARCHes (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
* assumption that their single CPU is online. The UP
* cpu_{online,possible,present}_masks are placebos. Changing them
* will have no useful affect on the following num_*_cpus()
@ -155,7 +155,7 @@ static __always_inline unsigned int cpumask_check(unsigned int cpu)
* cpumask_first - get the first cpu in a cpumask
* @srcp: the cpumask pointer
*
* Returns >= nr_cpu_ids if no cpus set.
* Return: >= nr_cpu_ids if no cpus set.
*/
static inline unsigned int cpumask_first(const struct cpumask *srcp)
{
@ -166,7 +166,7 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
* cpumask_first_zero - get the first unset cpu in a cpumask
* @srcp: the cpumask pointer
*
* Returns >= nr_cpu_ids if all cpus are set.
* Return: >= nr_cpu_ids if all cpus are set.
*/
static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
{
@ -178,7 +178,7 @@ static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
* @srcp1: the first input
* @srcp2: the second input
*
* Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
* Return: >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
*/
static inline
unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
@ -190,7 +190,7 @@ unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask
* cpumask_last - get the last CPU in a cpumask
* @srcp: - the cpumask pointer
*
* Returns >= nr_cpumask_bits if no CPUs set.
* Return: >= nr_cpumask_bits if no CPUs set.
*/
static inline unsigned int cpumask_last(const struct cpumask *srcp)
{
@ -199,10 +199,10 @@ static inline unsigned int cpumask_last(const struct cpumask *srcp)
/**
* cpumask_next - get the next cpu in a cpumask
* @n: the cpu prior to the place to search (ie. return will be > @n)
* @n: the cpu prior to the place to search (i.e. return will be > @n)
* @srcp: the cpumask pointer
*
* Returns >= nr_cpu_ids if no further cpus set.
* Return: >= nr_cpu_ids if no further cpus set.
*/
static inline
unsigned int cpumask_next(int n, const struct cpumask *srcp)
@ -215,10 +215,10 @@ unsigned int cpumask_next(int n, const struct cpumask *srcp)
/**
* cpumask_next_zero - get the next unset cpu in a cpumask
* @n: the cpu prior to the place to search (ie. return will be > @n)
* @n: the cpu prior to the place to search (i.e. return will be > @n)
* @srcp: the cpumask pointer
*
* Returns >= nr_cpu_ids if no further cpus unset.
* Return: >= nr_cpu_ids if no further cpus unset.
*/
static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
{
@ -254,11 +254,11 @@ unsigned int cpumask_any_distribute(const struct cpumask *srcp);
/**
* cpumask_next_and - get the next cpu in *src1p & *src2p
* @n: the cpu prior to the place to search (ie. return will be > @n)
* @n: the cpu prior to the place to search (i.e. return will be > @n)
* @src1p: the first cpumask pointer
* @src2p: the second cpumask pointer
*
* Returns >= nr_cpu_ids if no further cpus set in both.
* Return: >= nr_cpu_ids if no further cpus set in both.
*/
static inline
unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
@ -373,7 +373,7 @@ unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int sta
* @cpu: the cpu to ignore.
*
* Often used to find any cpu but smp_processor_id() in a mask.
* Returns >= nr_cpu_ids if no cpus set.
* Return: >= nr_cpu_ids if no cpus set.
*/
static inline
unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
@ -388,11 +388,11 @@ unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
}
/**
* cpumask_nth - get the first cpu in a cpumask
* cpumask_nth - get the Nth cpu in a cpumask
* @srcp: the cpumask pointer
* @cpu: the N'th cpu to find, starting from 0
* @cpu: the Nth cpu to find, starting from 0
*
* Returns >= nr_cpu_ids if such cpu doesn't exist.
* Return: >= nr_cpu_ids if such cpu doesn't exist.
*/
static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp)
{
@ -400,12 +400,12 @@ static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *s
}
/**
* cpumask_nth_and - get the first cpu in 2 cpumasks
* cpumask_nth_and - get the Nth cpu in 2 cpumasks
* @srcp1: the cpumask pointer
* @srcp2: the cpumask pointer
* @cpu: the N'th cpu to find, starting from 0
* @cpu: the Nth cpu to find, starting from 0
*
* Returns >= nr_cpu_ids if such cpu doesn't exist.
* Return: >= nr_cpu_ids if such cpu doesn't exist.
*/
static inline
unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1,
@ -416,12 +416,12 @@ unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1,
}
/**
* cpumask_nth_andnot - get the first cpu set in 1st cpumask, and clear in 2nd.
* cpumask_nth_andnot - get the Nth cpu set in 1st cpumask, and clear in 2nd.
* @srcp1: the cpumask pointer
* @srcp2: the cpumask pointer
* @cpu: the N'th cpu to find, starting from 0
* @cpu: the Nth cpu to find, starting from 0
*
* Returns >= nr_cpu_ids if such cpu doesn't exist.
* Return: >= nr_cpu_ids if such cpu doesn't exist.
*/
static inline
unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1,
@ -436,9 +436,9 @@ unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1,
* @srcp1: the cpumask pointer
* @srcp2: the cpumask pointer
* @srcp3: the cpumask pointer
* @cpu: the N'th cpu to find, starting from 0
* @cpu: the Nth cpu to find, starting from 0
*
* Returns >= nr_cpu_ids if such cpu doesn't exist.
* Return: >= nr_cpu_ids if such cpu doesn't exist.
*/
static __always_inline
unsigned int cpumask_nth_and_andnot(unsigned int cpu, const struct cpumask *srcp1,
@ -497,7 +497,7 @@ static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
* @cpu: cpu number (< nr_cpu_ids)
* @cpumask: the cpumask pointer
*
* Returns true if @cpu is set in @cpumask, else returns false
* Return: true if @cpu is set in @cpumask, else returns false
*/
static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
{
@ -509,9 +509,9 @@ static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpum
* @cpu: cpu number (< nr_cpu_ids)
* @cpumask: the cpumask pointer
*
* Returns true if @cpu is set in old bitmap of @cpumask, else returns false
*
* test_and_set_bit wrapper for cpumasks.
*
* Return: true if @cpu is set in old bitmap of @cpumask, else returns false
*/
static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
{
@ -523,9 +523,9 @@ static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cp
* @cpu: cpu number (< nr_cpu_ids)
* @cpumask: the cpumask pointer
*
* Returns true if @cpu is set in old bitmap of @cpumask, else returns false
*
* test_and_clear_bit wrapper for cpumasks.
*
* Return: true if @cpu is set in old bitmap of @cpumask, else returns false
*/
static __always_inline bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
{
@ -560,7 +560,7 @@ static inline void cpumask_clear(struct cpumask *dstp)
* @src1p: the first input
* @src2p: the second input
*
* If *@dstp is empty, returns false, else returns true
* Return: false if *@dstp is empty, else returns true
*/
static inline bool cpumask_and(struct cpumask *dstp,
const struct cpumask *src1p,
@ -603,7 +603,7 @@ static inline void cpumask_xor(struct cpumask *dstp,
* @src1p: the first input
* @src2p: the second input
*
* If *@dstp is empty, returns false, else returns true
* Return: false if *@dstp is empty, else returns true
*/
static inline bool cpumask_andnot(struct cpumask *dstp,
const struct cpumask *src1p,
@ -617,6 +617,8 @@ static inline bool cpumask_andnot(struct cpumask *dstp,
* cpumask_equal - *src1p == *src2p
* @src1p: the first input
* @src2p: the second input
*
* Return: true if the cpumasks are equal, false if not
*/
static inline bool cpumask_equal(const struct cpumask *src1p,
const struct cpumask *src2p)
@ -630,6 +632,9 @@ static inline bool cpumask_equal(const struct cpumask *src1p,
* @src1p: the first input
* @src2p: the second input
* @src3p: the third input
*
* Return: true if first cpumask ORed with second cpumask == third cpumask,
* otherwise false
*/
static inline bool cpumask_or_equal(const struct cpumask *src1p,
const struct cpumask *src2p,
@ -643,6 +648,9 @@ static inline bool cpumask_or_equal(const struct cpumask *src1p,
* cpumask_intersects - (*src1p & *src2p) != 0
* @src1p: the first input
* @src2p: the second input
*
* Return: true if first cpumask ANDed with second cpumask is non-empty,
* otherwise false
*/
static inline bool cpumask_intersects(const struct cpumask *src1p,
const struct cpumask *src2p)
@ -656,7 +664,7 @@ static inline bool cpumask_intersects(const struct cpumask *src1p,
* @src1p: the first input
* @src2p: the second input
*
* Returns true if *@src1p is a subset of *@src2p, else returns false
* Return: true if *@src1p is a subset of *@src2p, else returns false
*/
static inline bool cpumask_subset(const struct cpumask *src1p,
const struct cpumask *src2p)
@ -668,6 +676,8 @@ static inline bool cpumask_subset(const struct cpumask *src1p,
/**
* cpumask_empty - *srcp == 0
* @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
*
* Return: true if srcp is empty (has no bits set), else false
*/
static inline bool cpumask_empty(const struct cpumask *srcp)
{
@ -677,6 +687,8 @@ static inline bool cpumask_empty(const struct cpumask *srcp)
/**
* cpumask_full - *srcp == 0xFFFFFFFF...
* @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
*
* Return: true if srcp is full (has all bits set), else false
*/
static inline bool cpumask_full(const struct cpumask *srcp)
{
@ -686,6 +698,8 @@ static inline bool cpumask_full(const struct cpumask *srcp)
/**
* cpumask_weight - Count of bits in *srcp
* @srcp: the cpumask to count bits (< nr_cpu_ids) in.
*
* Return: count of bits set in *srcp
*/
static inline unsigned int cpumask_weight(const struct cpumask *srcp)
{
@ -696,6 +710,8 @@ static inline unsigned int cpumask_weight(const struct cpumask *srcp)
* cpumask_weight_and - Count of bits in (*srcp1 & *srcp2)
* @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
* @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
*
* Return: count of bits set in both *srcp1 and *srcp2
*/
static inline unsigned int cpumask_weight_and(const struct cpumask *srcp1,
const struct cpumask *srcp2)
@ -744,7 +760,7 @@ static inline void cpumask_copy(struct cpumask *dstp,
* cpumask_any - pick a "random" cpu from *srcp
* @srcp: the input cpumask
*
* Returns >= nr_cpu_ids if no cpus set.
* Return: >= nr_cpu_ids if no cpus set.
*/
#define cpumask_any(srcp) cpumask_first(srcp)
@ -753,7 +769,7 @@ static inline void cpumask_copy(struct cpumask *dstp,
* @mask1: the first input cpumask
* @mask2: the second input cpumask
*
* Returns >= nr_cpu_ids if no cpus set.
* Return: >= nr_cpu_ids if no cpus set.
*/
#define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
@ -769,7 +785,7 @@ static inline void cpumask_copy(struct cpumask *dstp,
* @len: the length of the buffer
* @dstp: the cpumask to set.
*
* Returns -errno, or 0 for success.
* Return: -errno, or 0 for success.
*/
static inline int cpumask_parse_user(const char __user *buf, int len,
struct cpumask *dstp)
@ -783,7 +799,7 @@ static inline int cpumask_parse_user(const char __user *buf, int len,
* @len: the length of the buffer
* @dstp: the cpumask to set.
*
* Returns -errno, or 0 for success.
* Return: -errno, or 0 for success.
*/
static inline int cpumask_parselist_user(const char __user *buf, int len,
struct cpumask *dstp)
@ -797,7 +813,7 @@ static inline int cpumask_parselist_user(const char __user *buf, int len,
* @buf: the buffer to extract from
* @dstp: the cpumask to set.
*
* Returns -errno, or 0 for success.
* Return: -errno, or 0 for success.
*/
static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
{
@ -809,7 +825,7 @@ static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
* @buf: the buffer to extract from
* @dstp: the cpumask to set.
*
* Returns -errno, or 0 for success.
* Return: -errno, or 0 for success.
*/
static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
{
@ -817,7 +833,9 @@ static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
}
/**
* cpumask_size - size to allocate for a 'struct cpumask' in bytes
* cpumask_size - calculate size to allocate for a 'struct cpumask' in bytes
*
* Return: size to allocate for a &struct cpumask in bytes
*/
static inline unsigned int cpumask_size(void)
{
@ -831,7 +849,7 @@ static inline unsigned int cpumask_size(void)
* little more difficult, we typedef cpumask_var_t to an array or a
* pointer: doing &mask on an array is a noop, so it still works.
*
* ie.
* i.e.
* cpumask_var_t tmpmask;
* if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
* return -ENOMEM;
@ -887,6 +905,8 @@ bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
* a nop returning a constant 1 (in <linux/cpumask.h>).
*
* See alloc_cpumask_var_node.
*
* Return: %true if allocation succeeded, %false if not
*/
static inline
bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
@ -1025,7 +1045,7 @@ set_cpu_dying(unsigned int cpu, bool dying)
}
/**
* to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
* to_cpumask - convert a NR_CPUS bitmap to a struct cpumask *
* @bitmap: the bitmap
*
* There are a few places where cpumask_var_t isn't appropriate and
@ -1068,6 +1088,8 @@ static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
* interface gives only a momentary snapshot and is not protected against
* concurrent CPU hotplug operations unless invoked from a cpuhp_lock held
* region.
*
* Return: momentary snapshot of the number of online CPUs
*/
static __always_inline unsigned int num_online_cpus(void)
{
@ -1160,7 +1182,7 @@ static inline bool cpu_dying(unsigned int cpu)
* @mask: the cpumask to copy
* @buf: the buffer to copy into
*
* Returns the length of the (null-terminated) @buf string, zero if
* Return: the length of the (null-terminated) @buf string, zero if
* nothing is copied.
*/
static inline ssize_t
@ -1183,7 +1205,7 @@ cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
* cpumask; Typically used by bin_attribute to export cpumask bitmask
* ABI.
*
* Returns the length of how many bytes have been copied, excluding
* Return: the length of how many bytes have been copied, excluding
* terminating '\0'.
*/
static inline ssize_t
@ -1204,6 +1226,9 @@ cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask,
*
* Everything is same with the above cpumap_print_bitmask_to_buf()
* except the print format.
*
* Return: the length of how many bytes have been copied, excluding
* terminating '\0'.
*/
static inline ssize_t
cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,

2
lib/Makefile
View File

@ -48,7 +48,7 @@ obj-y += bcd.o sort.o parser.o debug_locks.o random32.o \
bsearch.o find_bit.o llist.o lwq.o memweight.o kfifo.o \
percpu-refcount.o rhashtable.o base64.o \
once.o refcount.o rcuref.o usercopy.o errseq.o bucket_locks.o \
generic-radix-tree.o
generic-radix-tree.o bitmap-str.o
obj-$(CONFIG_STRING_SELFTEST) += test_string.o
obj-y += string_helpers.o
obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o

510
lib/bitmap-str.c Normal file
View File

@ -0,0 +1,510 @@
// SPDX-License-Identifier: GPL-2.0-only
#include <linux/bitmap.h>
#include <linux/ctype.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/hex.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include "kstrtox.h"
/**
* bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap
*
* @ubuf: pointer to user buffer containing string.
* @ulen: buffer size in bytes. If string is smaller than this
* then it must be terminated with a \0.
* @maskp: pointer to bitmap array that will contain result.
* @nmaskbits: size of bitmap, in bits.
*/
int bitmap_parse_user(const char __user *ubuf,
unsigned int ulen, unsigned long *maskp,
int nmaskbits)
{
char *buf;
int ret;
buf = memdup_user_nul(ubuf, ulen);
if (IS_ERR(buf))
return PTR_ERR(buf);
ret = bitmap_parse(buf, UINT_MAX, maskp, nmaskbits);
kfree(buf);
return ret;
}
EXPORT_SYMBOL(bitmap_parse_user);
/**
* bitmap_print_to_pagebuf - convert bitmap to list or hex format ASCII string
* @list: indicates whether the bitmap must be list
* @buf: page aligned buffer into which string is placed
* @maskp: pointer to bitmap to convert
* @nmaskbits: size of bitmap, in bits
*
* Output format is a comma-separated list of decimal numbers and
* ranges if list is specified or hex digits grouped into comma-separated
* sets of 8 digits/set. Returns the number of characters written to buf.
*
* It is assumed that @buf is a pointer into a PAGE_SIZE, page-aligned
* area and that sufficient storage remains at @buf to accommodate the
* bitmap_print_to_pagebuf() output. Returns the number of characters
* actually printed to @buf, excluding terminating '\0'.
*/
int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
int nmaskbits)
{
ptrdiff_t len = PAGE_SIZE - offset_in_page(buf);
return list ? scnprintf(buf, len, "%*pbl\n", nmaskbits, maskp) :
scnprintf(buf, len, "%*pb\n", nmaskbits, maskp);
}
EXPORT_SYMBOL(bitmap_print_to_pagebuf);
/**
* bitmap_print_to_buf - convert bitmap to list or hex format ASCII string
* @list: indicates whether the bitmap must be list
* true: print in decimal list format
* false: print in hexadecimal bitmask format
* @buf: buffer into which string is placed
* @maskp: pointer to bitmap to convert
* @nmaskbits: size of bitmap, in bits
* @off: in the string from which we are copying, We copy to @buf
* @count: the maximum number of bytes to print
*/
static int bitmap_print_to_buf(bool list, char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count)
{
const char *fmt = list ? "%*pbl\n" : "%*pb\n";
ssize_t size;
void *data;
data = kasprintf(GFP_KERNEL, fmt, nmaskbits, maskp);
if (!data)
return -ENOMEM;
size = memory_read_from_buffer(buf, count, &off, data, strlen(data) + 1);
kfree(data);
return size;
}
/**
* bitmap_print_bitmask_to_buf - convert bitmap to hex bitmask format ASCII string
* @buf: buffer into which string is placed
* @maskp: pointer to bitmap to convert
* @nmaskbits: size of bitmap, in bits
* @off: in the string from which we are copying, We copy to @buf
* @count: the maximum number of bytes to print
*
* The bitmap_print_to_pagebuf() is used indirectly via its cpumap wrapper
* cpumap_print_to_pagebuf() or directly by drivers to export hexadecimal
* bitmask and decimal list to userspace by sysfs ABI.
* Drivers might be using a normal attribute for this kind of ABIs. A
* normal attribute typically has show entry as below::
*
* static ssize_t example_attribute_show(struct device *dev,
* struct device_attribute *attr, char *buf)
* {
* ...
* return bitmap_print_to_pagebuf(true, buf, &mask, nr_trig_max);
* }
*
* show entry of attribute has no offset and count parameters and this
* means the file is limited to one page only.
* bitmap_print_to_pagebuf() API works terribly well for this kind of
* normal attribute with buf parameter and without offset, count::
*
* bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
* int nmaskbits)
* {
* }
*
* The problem is once we have a large bitmap, we have a chance to get a
* bitmask or list more than one page. Especially for list, it could be
* as complex as 0,3,5,7,9,... We have no simple way to know it exact size.
* It turns out bin_attribute is a way to break this limit. bin_attribute
* has show entry as below::
*
* static ssize_t
* example_bin_attribute_show(struct file *filp, struct kobject *kobj,
* struct bin_attribute *attr, char *buf,
* loff_t offset, size_t count)
* {
* ...
* }
*
* With the new offset and count parameters, this makes sysfs ABI be able
* to support file size more than one page. For example, offset could be
* >= 4096.
* bitmap_print_bitmask_to_buf(), bitmap_print_list_to_buf() wit their
* cpumap wrapper cpumap_print_bitmask_to_buf(), cpumap_print_list_to_buf()
* make those drivers be able to support large bitmask and list after they
* move to use bin_attribute. In result, we have to pass the corresponding
* parameters such as off, count from bin_attribute show entry to this API.
*
* The role of cpumap_print_bitmask_to_buf() and cpumap_print_list_to_buf()
* is similar with cpumap_print_to_pagebuf(), the difference is that
* bitmap_print_to_pagebuf() mainly serves sysfs attribute with the assumption
* the destination buffer is exactly one page and won't be more than one page.
* cpumap_print_bitmask_to_buf() and cpumap_print_list_to_buf(), on the other
* hand, mainly serves bin_attribute which doesn't work with exact one page,
* and it can break the size limit of converted decimal list and hexadecimal
* bitmask.
*
* WARNING!
*
* This function is not a replacement for sprintf() or bitmap_print_to_pagebuf().
* It is intended to workaround sysfs limitations discussed above and should be
* used carefully in general case for the following reasons:
*
* - Time complexity is O(nbits^2/count), comparing to O(nbits) for snprintf().
* - Memory complexity is O(nbits), comparing to O(1) for snprintf().
* - @off and @count are NOT offset and number of bits to print.
* - If printing part of bitmap as list, the resulting string is not a correct
* list representation of bitmap. Particularly, some bits within or out of
* related interval may be erroneously set or unset. The format of the string
* may be broken, so bitmap_parselist-like parser may fail parsing it.
* - If printing the whole bitmap as list by parts, user must ensure the order
* of calls of the function such that the offset is incremented linearly.
* - If printing the whole bitmap as list by parts, user must keep bitmap
* unchanged between the very first and very last call. Otherwise concatenated
* result may be incorrect, and format may be broken.
*
* Returns the number of characters actually printed to @buf
*/
int bitmap_print_bitmask_to_buf(char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count)
{
return bitmap_print_to_buf(false, buf, maskp, nmaskbits, off, count);
}
EXPORT_SYMBOL(bitmap_print_bitmask_to_buf);
/**
* bitmap_print_list_to_buf - convert bitmap to decimal list format ASCII string
* @buf: buffer into which string is placed
* @maskp: pointer to bitmap to convert
* @nmaskbits: size of bitmap, in bits
* @off: in the string from which we are copying, We copy to @buf
* @count: the maximum number of bytes to print
*
* Everything is same with the above bitmap_print_bitmask_to_buf() except
* the print format.
*/
int bitmap_print_list_to_buf(char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count)
{
return bitmap_print_to_buf(true, buf, maskp, nmaskbits, off, count);
}
EXPORT_SYMBOL(bitmap_print_list_to_buf);
/*
* Region 9-38:4/10 describes the following bitmap structure:
* 0 9 12 18 38 N
* .........****......****......****..................
* ^ ^ ^ ^ ^
* start off group_len end nbits
*/
struct region {
unsigned int start;
unsigned int off;
unsigned int group_len;
unsigned int end;
unsigned int nbits;
};
static void bitmap_set_region(const struct region *r, unsigned long *bitmap)
{
unsigned int start;
for (start = r->start; start <= r->end; start += r->group_len)
bitmap_set(bitmap, start, min(r->end - start + 1, r->off));
}
static int bitmap_check_region(const struct region *r)
{
if (r->start > r->end || r->group_len == 0 || r->off > r->group_len)
return -EINVAL;
if (r->end >= r->nbits)
return -ERANGE;
return 0;
}
static const char *bitmap_getnum(const char *str, unsigned int *num,
unsigned int lastbit)
{
unsigned long long n;
unsigned int len;
if (str[0] == 'N') {
*num = lastbit;
return str + 1;
}
len = _parse_integer(str, 10, &n);
if (!len)
return ERR_PTR(-EINVAL);
if (len & KSTRTOX_OVERFLOW || n != (unsigned int)n)
return ERR_PTR(-EOVERFLOW);
*num = n;
return str + len;
}
static inline bool end_of_str(char c)
{
return c == '\0' || c == '\n';
}
static inline bool __end_of_region(char c)
{
return isspace(c) || c == ',';
}
static inline bool end_of_region(char c)
{
return __end_of_region(c) || end_of_str(c);
}
/*
* The format allows commas and whitespaces at the beginning
* of the region.
*/
static const char *bitmap_find_region(const char *str)
{
while (__end_of_region(*str))
str++;
return end_of_str(*str) ? NULL : str;
}
static const char *bitmap_find_region_reverse(const char *start, const char *end)
{
while (start <= end && __end_of_region(*end))
end--;
return end;
}
static const char *bitmap_parse_region(const char *str, struct region *r)
{
unsigned int lastbit = r->nbits - 1;
if (!strncasecmp(str, "all", 3)) {
r->start = 0;
r->end = lastbit;
str += 3;
goto check_pattern;
}
str = bitmap_getnum(str, &r->start, lastbit);
if (IS_ERR(str))
return str;
if (end_of_region(*str))
goto no_end;
if (*str != '-')
return ERR_PTR(-EINVAL);
str = bitmap_getnum(str + 1, &r->end, lastbit);
if (IS_ERR(str))
return str;
check_pattern:
if (end_of_region(*str))
goto no_pattern;
if (*str != ':')
return ERR_PTR(-EINVAL);
str = bitmap_getnum(str + 1, &r->off, lastbit);
if (IS_ERR(str))
return str;
if (*str != '/')
return ERR_PTR(-EINVAL);
return bitmap_getnum(str + 1, &r->group_len, lastbit);
no_end:
r->end = r->start;
no_pattern:
r->off = r->end + 1;
r->group_len = r->end + 1;
return end_of_str(*str) ? NULL : str;
}
/**
* bitmap_parselist - convert list format ASCII string to bitmap
* @buf: read user string from this buffer; must be terminated
* with a \0 or \n.
* @maskp: write resulting mask here
* @nmaskbits: number of bits in mask to be written
*
* Input format is a comma-separated list of decimal numbers and
* ranges. Consecutively set bits are shown as two hyphen-separated
* decimal numbers, the smallest and largest bit numbers set in
* the range.
* Optionally each range can be postfixed to denote that only parts of it
* should be set. The range will divided to groups of specific size.
* From each group will be used only defined amount of bits.
* Syntax: range:used_size/group_size
* Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769
* The value 'N' can be used as a dynamically substituted token for the
* maximum allowed value; i.e (nmaskbits - 1). Keep in mind that it is
* dynamic, so if system changes cause the bitmap width to change, such
* as more cores in a CPU list, then any ranges using N will also change.
*
* Returns: 0 on success, -errno on invalid input strings. Error values:
*
* - ``-EINVAL``: wrong region format
* - ``-EINVAL``: invalid character in string
* - ``-ERANGE``: bit number specified too large for mask
* - ``-EOVERFLOW``: integer overflow in the input parameters
*/
int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits)
{
struct region r;
long ret;
r.nbits = nmaskbits;
bitmap_zero(maskp, r.nbits);
while (buf) {
buf = bitmap_find_region(buf);
if (buf == NULL)
return 0;
buf = bitmap_parse_region(buf, &r);
if (IS_ERR(buf))
return PTR_ERR(buf);
ret = bitmap_check_region(&r);
if (ret)
return ret;
bitmap_set_region(&r, maskp);
}
return 0;
}
EXPORT_SYMBOL(bitmap_parselist);
/**
* bitmap_parselist_user() - convert user buffer's list format ASCII
* string to bitmap
*
* @ubuf: pointer to user buffer containing string.
* @ulen: buffer size in bytes. If string is smaller than this
* then it must be terminated with a \0.
* @maskp: pointer to bitmap array that will contain result.
* @nmaskbits: size of bitmap, in bits.
*
* Wrapper for bitmap_parselist(), providing it with user buffer.
*/
int bitmap_parselist_user(const char __user *ubuf,
unsigned int ulen, unsigned long *maskp,
int nmaskbits)
{
char *buf;
int ret;
buf = memdup_user_nul(ubuf, ulen);
if (IS_ERR(buf))
return PTR_ERR(buf);
ret = bitmap_parselist(buf, maskp, nmaskbits);
kfree(buf);
return ret;
}
EXPORT_SYMBOL(bitmap_parselist_user);
static const char *bitmap_get_x32_reverse(const char *start,
const char *end, u32 *num)
{
u32 ret = 0;
int c, i;
for (i = 0; i < 32; i += 4) {
c = hex_to_bin(*end--);
if (c < 0)
return ERR_PTR(-EINVAL);
ret |= c << i;
if (start > end || __end_of_region(*end))
goto out;
}
if (hex_to_bin(*end--) >= 0)
return ERR_PTR(-EOVERFLOW);
out:
*num = ret;
return end;
}
/**
* bitmap_parse - convert an ASCII hex string into a bitmap.
* @start: pointer to buffer containing string.
* @buflen: buffer size in bytes. If string is smaller than this
* then it must be terminated with a \0 or \n. In that case,
* UINT_MAX may be provided instead of string length.
* @maskp: pointer to bitmap array that will contain result.
* @nmaskbits: size of bitmap, in bits.
*
* Commas group hex digits into chunks. Each chunk defines exactly 32
* bits of the resultant bitmask. No chunk may specify a value larger
* than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value
* then leading 0-bits are prepended. %-EINVAL is returned for illegal
* characters. Grouping such as "1,,5", ",44", "," or "" is allowed.
* Leading, embedded and trailing whitespace accepted.
*/
int bitmap_parse(const char *start, unsigned int buflen,
unsigned long *maskp, int nmaskbits)
{
const char *end = strnchrnul(start, buflen, '\n') - 1;
int chunks = BITS_TO_U32(nmaskbits);
u32 *bitmap = (u32 *)maskp;
int unset_bit;
int chunk;
for (chunk = 0; ; chunk++) {
end = bitmap_find_region_reverse(start, end);
if (start > end)
break;
if (!chunks--)
return -EOVERFLOW;
#if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN)
end = bitmap_get_x32_reverse(start, end, &bitmap[chunk ^ 1]);
#else
end = bitmap_get_x32_reverse(start, end, &bitmap[chunk]);
#endif
if (IS_ERR(end))
return PTR_ERR(end);
}
unset_bit = (BITS_TO_U32(nmaskbits) - chunks) * 32;
if (unset_bit < nmaskbits) {
bitmap_clear(maskp, unset_bit, nmaskbits - unset_bit);
return 0;
}
if (find_next_bit(maskp, unset_bit, nmaskbits) != unset_bit)
return -EOVERFLOW;
return 0;
}
EXPORT_SYMBOL(bitmap_parse);

680
lib/bitmap.c
View File

@ -6,21 +6,10 @@
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/ctype.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/thread_info.h>
#include <linux/uaccess.h>
#include <asm/page.h>
#include "kstrtox.h"
/**
* DOC: bitmap introduction
@ -440,508 +429,6 @@ again:
}
EXPORT_SYMBOL(bitmap_find_next_zero_area_off);
/*
* Bitmap printing & parsing functions: first version by Nadia Yvette Chambers,
* second version by Paul Jackson, third by Joe Korty.
*/
/**
* bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap
*
* @ubuf: pointer to user buffer containing string.
* @ulen: buffer size in bytes. If string is smaller than this
* then it must be terminated with a \0.
* @maskp: pointer to bitmap array that will contain result.
* @nmaskbits: size of bitmap, in bits.
*/
int bitmap_parse_user(const char __user *ubuf,
unsigned int ulen, unsigned long *maskp,
int nmaskbits)
{
char *buf;
int ret;
buf = memdup_user_nul(ubuf, ulen);
if (IS_ERR(buf))
return PTR_ERR(buf);
ret = bitmap_parse(buf, UINT_MAX, maskp, nmaskbits);
kfree(buf);
return ret;
}
EXPORT_SYMBOL(bitmap_parse_user);
/**
* bitmap_print_to_pagebuf - convert bitmap to list or hex format ASCII string
* @list: indicates whether the bitmap must be list
* @buf: page aligned buffer into which string is placed
* @maskp: pointer to bitmap to convert
* @nmaskbits: size of bitmap, in bits
*
* Output format is a comma-separated list of decimal numbers and
* ranges if list is specified or hex digits grouped into comma-separated
* sets of 8 digits/set. Returns the number of characters written to buf.
*
* It is assumed that @buf is a pointer into a PAGE_SIZE, page-aligned
* area and that sufficient storage remains at @buf to accommodate the
* bitmap_print_to_pagebuf() output. Returns the number of characters
* actually printed to @buf, excluding terminating '\0'.
*/
int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
int nmaskbits)
{
ptrdiff_t len = PAGE_SIZE - offset_in_page(buf);
return list ? scnprintf(buf, len, "%*pbl\n", nmaskbits, maskp) :
scnprintf(buf, len, "%*pb\n", nmaskbits, maskp);
}
EXPORT_SYMBOL(bitmap_print_to_pagebuf);
/**
* bitmap_print_to_buf - convert bitmap to list or hex format ASCII string
* @list: indicates whether the bitmap must be list
* true: print in decimal list format
* false: print in hexadecimal bitmask format
* @buf: buffer into which string is placed
* @maskp: pointer to bitmap to convert
* @nmaskbits: size of bitmap, in bits
* @off: in the string from which we are copying, We copy to @buf
* @count: the maximum number of bytes to print
*/
static int bitmap_print_to_buf(bool list, char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count)
{
const char *fmt = list ? "%*pbl\n" : "%*pb\n";
ssize_t size;
void *data;
data = kasprintf(GFP_KERNEL, fmt, nmaskbits, maskp);
if (!data)
return -ENOMEM;
size = memory_read_from_buffer(buf, count, &off, data, strlen(data) + 1);
kfree(data);
return size;
}
/**
* bitmap_print_bitmask_to_buf - convert bitmap to hex bitmask format ASCII string
* @buf: buffer into which string is placed
* @maskp: pointer to bitmap to convert
* @nmaskbits: size of bitmap, in bits
* @off: in the string from which we are copying, We copy to @buf
* @count: the maximum number of bytes to print
*
* The bitmap_print_to_pagebuf() is used indirectly via its cpumap wrapper
* cpumap_print_to_pagebuf() or directly by drivers to export hexadecimal
* bitmask and decimal list to userspace by sysfs ABI.
* Drivers might be using a normal attribute for this kind of ABIs. A
* normal attribute typically has show entry as below::
*
* static ssize_t example_attribute_show(struct device *dev,
* struct device_attribute *attr, char *buf)
* {
* ...
* return bitmap_print_to_pagebuf(true, buf, &mask, nr_trig_max);
* }
*
* show entry of attribute has no offset and count parameters and this
* means the file is limited to one page only.
* bitmap_print_to_pagebuf() API works terribly well for this kind of
* normal attribute with buf parameter and without offset, count::
*
* bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
* int nmaskbits)
* {
* }
*
* The problem is once we have a large bitmap, we have a chance to get a
* bitmask or list more than one page. Especially for list, it could be
* as complex as 0,3,5,7,9,... We have no simple way to know it exact size.
* It turns out bin_attribute is a way to break this limit. bin_attribute
* has show entry as below::
*
* static ssize_t
* example_bin_attribute_show(struct file *filp, struct kobject *kobj,
* struct bin_attribute *attr, char *buf,
* loff_t offset, size_t count)
* {
* ...
* }
*
* With the new offset and count parameters, this makes sysfs ABI be able
* to support file size more than one page. For example, offset could be
* >= 4096.
* bitmap_print_bitmask_to_buf(), bitmap_print_list_to_buf() wit their
* cpumap wrapper cpumap_print_bitmask_to_buf(), cpumap_print_list_to_buf()
* make those drivers be able to support large bitmask and list after they
* move to use bin_attribute. In result, we have to pass the corresponding
* parameters such as off, count from bin_attribute show entry to this API.
*
* The role of cpumap_print_bitmask_to_buf() and cpumap_print_list_to_buf()
* is similar with cpumap_print_to_pagebuf(), the difference is that
* bitmap_print_to_pagebuf() mainly serves sysfs attribute with the assumption
* the destination buffer is exactly one page and won't be more than one page.
* cpumap_print_bitmask_to_buf() and cpumap_print_list_to_buf(), on the other
* hand, mainly serves bin_attribute which doesn't work with exact one page,
* and it can break the size limit of converted decimal list and hexadecimal
* bitmask.
*
* WARNING!
*
* This function is not a replacement for sprintf() or bitmap_print_to_pagebuf().
* It is intended to workaround sysfs limitations discussed above and should be
* used carefully in general case for the following reasons:
*
* - Time complexity is O(nbits^2/count), comparing to O(nbits) for snprintf().
* - Memory complexity is O(nbits), comparing to O(1) for snprintf().
* - @off and @count are NOT offset and number of bits to print.
* - If printing part of bitmap as list, the resulting string is not a correct
* list representation of bitmap. Particularly, some bits within or out of
* related interval may be erroneously set or unset. The format of the string
* may be broken, so bitmap_parselist-like parser may fail parsing it.
* - If printing the whole bitmap as list by parts, user must ensure the order
* of calls of the function such that the offset is incremented linearly.
* - If printing the whole bitmap as list by parts, user must keep bitmap
* unchanged between the very first and very last call. Otherwise concatenated
* result may be incorrect, and format may be broken.
*
* Returns the number of characters actually printed to @buf
*/
int bitmap_print_bitmask_to_buf(char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count)
{
return bitmap_print_to_buf(false, buf, maskp, nmaskbits, off, count);
}
EXPORT_SYMBOL(bitmap_print_bitmask_to_buf);
/**
* bitmap_print_list_to_buf - convert bitmap to decimal list format ASCII string
* @buf: buffer into which string is placed
* @maskp: pointer to bitmap to convert
* @nmaskbits: size of bitmap, in bits
* @off: in the string from which we are copying, We copy to @buf
* @count: the maximum number of bytes to print
*
* Everything is same with the above bitmap_print_bitmask_to_buf() except
* the print format.
*/
int bitmap_print_list_to_buf(char *buf, const unsigned long *maskp,
int nmaskbits, loff_t off, size_t count)
{
return bitmap_print_to_buf(true, buf, maskp, nmaskbits, off, count);
}
EXPORT_SYMBOL(bitmap_print_list_to_buf);
/*
* Region 9-38:4/10 describes the following bitmap structure:
* 0 9 12 18 38 N
* .........****......****......****..................
* ^ ^ ^ ^ ^
* start off group_len end nbits
*/
struct region {
unsigned int start;
unsigned int off;
unsigned int group_len;
unsigned int end;
unsigned int nbits;
};
static void bitmap_set_region(const struct region *r, unsigned long *bitmap)
{
unsigned int start;
for (start = r->start; start <= r->end; start += r->group_len)
bitmap_set(bitmap, start, min(r->end - start + 1, r->off));
}
static int bitmap_check_region(const struct region *r)
{
if (r->start > r->end || r->group_len == 0 || r->off > r->group_len)
return -EINVAL;
if (r->end >= r->nbits)
return -ERANGE;
return 0;
}
static const char *bitmap_getnum(const char *str, unsigned int *num,
unsigned int lastbit)
{
unsigned long long n;
unsigned int len;
if (str[0] == 'N') {
*num = lastbit;
return str + 1;
}
len = _parse_integer(str, 10, &n);
if (!len)
return ERR_PTR(-EINVAL);
if (len & KSTRTOX_OVERFLOW || n != (unsigned int)n)
return ERR_PTR(-EOVERFLOW);
*num = n;
return str + len;
}
static inline bool end_of_str(char c)
{
return c == '\0' || c == '\n';
}
static inline bool __end_of_region(char c)
{
return isspace(c) || c == ',';
}
static inline bool end_of_region(char c)
{
return __end_of_region(c) || end_of_str(c);
}
/*
* The format allows commas and whitespaces at the beginning
* of the region.
*/
static const char *bitmap_find_region(const char *str)
{
while (__end_of_region(*str))
str++;
return end_of_str(*str) ? NULL : str;
}
static const char *bitmap_find_region_reverse(const char *start, const char *end)
{
while (start <= end && __end_of_region(*end))
end--;
return end;
}
static const char *bitmap_parse_region(const char *str, struct region *r)
{
unsigned int lastbit = r->nbits - 1;
if (!strncasecmp(str, "all", 3)) {
r->start = 0;
r->end = lastbit;
str += 3;
goto check_pattern;
}
str = bitmap_getnum(str, &r->start, lastbit);
if (IS_ERR(str))
return str;
if (end_of_region(*str))
goto no_end;
if (*str != '-')
return ERR_PTR(-EINVAL);
str = bitmap_getnum(str + 1, &r->end, lastbit);
if (IS_ERR(str))
return str;
check_pattern:
if (end_of_region(*str))
goto no_pattern;
if (*str != ':')
return ERR_PTR(-EINVAL);
str = bitmap_getnum(str + 1, &r->off, lastbit);
if (IS_ERR(str))
return str;
if (*str != '/')
return ERR_PTR(-EINVAL);
return bitmap_getnum(str + 1, &r->group_len, lastbit);
no_end:
r->end = r->start;
no_pattern:
r->off = r->end + 1;
r->group_len = r->end + 1;
return end_of_str(*str) ? NULL : str;
}
/**
* bitmap_parselist - convert list format ASCII string to bitmap
* @buf: read user string from this buffer; must be terminated
* with a \0 or \n.
* @maskp: write resulting mask here
* @nmaskbits: number of bits in mask to be written
*
* Input format is a comma-separated list of decimal numbers and
* ranges. Consecutively set bits are shown as two hyphen-separated
* decimal numbers, the smallest and largest bit numbers set in
* the range.
* Optionally each range can be postfixed to denote that only parts of it
* should be set. The range will divided to groups of specific size.
* From each group will be used only defined amount of bits.
* Syntax: range:used_size/group_size
* Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769
* The value 'N' can be used as a dynamically substituted token for the
* maximum allowed value; i.e (nmaskbits - 1). Keep in mind that it is
* dynamic, so if system changes cause the bitmap width to change, such
* as more cores in a CPU list, then any ranges using N will also change.
*
* Returns: 0 on success, -errno on invalid input strings. Error values:
*
* - ``-EINVAL``: wrong region format
* - ``-EINVAL``: invalid character in string
* - ``-ERANGE``: bit number specified too large for mask
* - ``-EOVERFLOW``: integer overflow in the input parameters
*/
int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits)
{
struct region r;
long ret;
r.nbits = nmaskbits;
bitmap_zero(maskp, r.nbits);
while (buf) {
buf = bitmap_find_region(buf);
if (buf == NULL)
return 0;
buf = bitmap_parse_region(buf, &r);
if (IS_ERR(buf))
return PTR_ERR(buf);
ret = bitmap_check_region(&r);
if (ret)
return ret;
bitmap_set_region(&r, maskp);
}
return 0;
}
EXPORT_SYMBOL(bitmap_parselist);
/**
* bitmap_parselist_user() - convert user buffer's list format ASCII
* string to bitmap
*
* @ubuf: pointer to user buffer containing string.
* @ulen: buffer size in bytes. If string is smaller than this
* then it must be terminated with a \0.
* @maskp: pointer to bitmap array that will contain result.
* @nmaskbits: size of bitmap, in bits.
*
* Wrapper for bitmap_parselist(), providing it with user buffer.
*/
int bitmap_parselist_user(const char __user *ubuf,
unsigned int ulen, unsigned long *maskp,
int nmaskbits)
{
char *buf;
int ret;
buf = memdup_user_nul(ubuf, ulen);
if (IS_ERR(buf))
return PTR_ERR(buf);
ret = bitmap_parselist(buf, maskp, nmaskbits);
kfree(buf);
return ret;
}
EXPORT_SYMBOL(bitmap_parselist_user);
static const char *bitmap_get_x32_reverse(const char *start,
const char *end, u32 *num)
{
u32 ret = 0;
int c, i;
for (i = 0; i < 32; i += 4) {
c = hex_to_bin(*end--);
if (c < 0)
return ERR_PTR(-EINVAL);
ret |= c << i;
if (start > end || __end_of_region(*end))
goto out;
}
if (hex_to_bin(*end--) >= 0)
return ERR_PTR(-EOVERFLOW);
out:
*num = ret;
return end;
}
/**
* bitmap_parse - convert an ASCII hex string into a bitmap.
* @start: pointer to buffer containing string.
* @buflen: buffer size in bytes. If string is smaller than this
* then it must be terminated with a \0 or \n. In that case,
* UINT_MAX may be provided instead of string length.
* @maskp: pointer to bitmap array that will contain result.
* @nmaskbits: size of bitmap, in bits.
*
* Commas group hex digits into chunks. Each chunk defines exactly 32
* bits of the resultant bitmask. No chunk may specify a value larger
* than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value
* then leading 0-bits are prepended. %-EINVAL is returned for illegal
* characters. Grouping such as "1,,5", ",44", "," or "" is allowed.
* Leading, embedded and trailing whitespace accepted.
*/
int bitmap_parse(const char *start, unsigned int buflen,
unsigned long *maskp, int nmaskbits)
{
const char *end = strnchrnul(start, buflen, '\n') - 1;
int chunks = BITS_TO_U32(nmaskbits);
u32 *bitmap = (u32 *)maskp;
int unset_bit;
int chunk;
for (chunk = 0; ; chunk++) {
end = bitmap_find_region_reverse(start, end);
if (start > end)
break;
if (!chunks--)
return -EOVERFLOW;
#if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN)
end = bitmap_get_x32_reverse(start, end, &bitmap[chunk ^ 1]);
#else
end = bitmap_get_x32_reverse(start, end, &bitmap[chunk]);
#endif
if (IS_ERR(end))
return PTR_ERR(end);
}
unset_bit = (BITS_TO_U32(nmaskbits) - chunks) * 32;
if (unset_bit < nmaskbits) {
bitmap_clear(maskp, unset_bit, nmaskbits - unset_bit);
return 0;
}
if (find_next_bit(maskp, unset_bit, nmaskbits) != unset_bit)
return -EOVERFLOW;
return 0;
}
EXPORT_SYMBOL(bitmap_parse);
/**
* bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap
* @buf: pointer to a bitmap
@ -988,7 +475,7 @@ static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigne
* to @dst.
*
* The positions of unset bits in @old are mapped to themselves
* (the identify map).
* (the identity map).
*
* Apply the above specified mapping to @src, placing the result in
* @dst, clearing any bits previously set in @dst.
@ -1037,7 +524,7 @@ EXPORT_SYMBOL(bitmap_remap);
* the position of the m-th set bit in @new, where m == n % w.
*
* The positions of unset bits in @old are mapped to themselves
* (the identify map).
* (the identity map).
*
* Apply the above specified mapping to bit position @oldbit, returning
* the new bit position.
@ -1220,169 +707,6 @@ void bitmap_fold(unsigned long *dst, const unsigned long *orig,
}
#endif /* CONFIG_NUMA */
/*
* Common code for bitmap_*_region() routines.
* bitmap: array of unsigned longs corresponding to the bitmap
* pos: the beginning of the region
* order: region size (log base 2 of number of bits)
* reg_op: operation(s) to perform on that region of bitmap
*
* Can set, verify and/or release a region of bits in a bitmap,
* depending on which combination of REG_OP_* flag bits is set.
*
* A region of a bitmap is a sequence of bits in the bitmap, of
* some size '1 << order' (a power of two), aligned to that same
* '1 << order' power of two.
*
* Returns 1 if REG_OP_ISFREE succeeds (region is all zero bits).
* Returns 0 in all other cases and reg_ops.
*/
enum {
REG_OP_ISFREE, /* true if region is all zero bits */
REG_OP_ALLOC, /* set all bits in region */
REG_OP_RELEASE, /* clear all bits in region */
};
static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op)
{
int nbits_reg; /* number of bits in region */
int index; /* index first long of region in bitmap */
int offset; /* bit offset region in bitmap[index] */
int nlongs_reg; /* num longs spanned by region in bitmap */
int nbitsinlong; /* num bits of region in each spanned long */
unsigned long mask; /* bitmask for one long of region */
int i; /* scans bitmap by longs */
int ret = 0; /* return value */
/*
* Either nlongs_reg == 1 (for small orders that fit in one long)
* or (offset == 0 && mask == ~0UL) (for larger multiword orders.)
*/
nbits_reg = 1 << order;
index = pos / BITS_PER_LONG;
offset = pos - (index * BITS_PER_LONG);
nlongs_reg = BITS_TO_LONGS(nbits_reg);
nbitsinlong = min(nbits_reg, BITS_PER_LONG);
/*
* Can't do "mask = (1UL << nbitsinlong) - 1", as that
* overflows if nbitsinlong == BITS_PER_LONG.
*/
mask = (1UL << (nbitsinlong - 1));
mask += mask - 1;
mask <<= offset;
switch (reg_op) {
case REG_OP_ISFREE:
for (i = 0; i < nlongs_reg; i++) {
if (bitmap[index + i] & mask)
goto done;
}
ret = 1; /* all bits in region free (zero) */
break;
case REG_OP_ALLOC:
for (i = 0; i < nlongs_reg; i++)
bitmap[index + i] |= mask;
break;
case REG_OP_RELEASE:
for (i = 0; i < nlongs_reg; i++)
bitmap[index + i] &= ~mask;
break;
}
done:
return ret;
}
/**
* bitmap_find_free_region - find a contiguous aligned mem region
* @bitmap: array of unsigned longs corresponding to the bitmap
* @bits: number of bits in the bitmap
* @order: region size (log base 2 of number of bits) to find
*
* Find a region of free (zero) bits in a @bitmap of @bits bits and
* allocate them (set them to one). Only consider regions of length
* a power (@order) of two, aligned to that power of two, which
* makes the search algorithm much faster.
*
* Return the bit offset in bitmap of the allocated region,
* or -errno on failure.
*/
int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order)
{
unsigned int pos, end; /* scans bitmap by regions of size order */
for (pos = 0 ; (end = pos + (1U << order)) <= bits; pos = end) {
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
continue;
__reg_op(bitmap, pos, order, REG_OP_ALLOC);
return pos;
}
return -ENOMEM;
}
EXPORT_SYMBOL(bitmap_find_free_region);
/**
* bitmap_release_region - release allocated bitmap region
* @bitmap: array of unsigned longs corresponding to the bitmap
* @pos: beginning of bit region to release
* @order: region size (log base 2 of number of bits) to release
*
* This is the complement to __bitmap_find_free_region() and releases
* the found region (by clearing it in the bitmap).
*
* No return value.
*/
void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order)
{
__reg_op(bitmap, pos, order, REG_OP_RELEASE);
}
EXPORT_SYMBOL(bitmap_release_region);
/**
* bitmap_allocate_region - allocate bitmap region
* @bitmap: array of unsigned longs corresponding to the bitmap
* @pos: beginning of bit region to allocate
* @order: region size (log base 2 of number of bits) to allocate
*
* Allocate (set bits in) a specified region of a bitmap.
*
* Return 0 on success, or %-EBUSY if specified region wasn't
* free (not all bits were zero).
*/
int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
{
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
return -EBUSY;
return __reg_op(bitmap, pos, order, REG_OP_ALLOC);
}
EXPORT_SYMBOL(bitmap_allocate_region);
/**
* bitmap_copy_le - copy a bitmap, putting the bits into little-endian order.
* @dst: destination buffer
* @src: bitmap to copy
* @nbits: number of bits in the bitmap
*
* Require nbits % BITS_PER_LONG == 0.
*/
#ifdef __BIG_ENDIAN
void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits)
{
unsigned int i;
for (i = 0; i < nbits/BITS_PER_LONG; i++) {
if (BITS_PER_LONG == 64)
dst[i] = cpu_to_le64(src[i]);
else
dst[i] = cpu_to_le32(src[i]);
}
}
EXPORT_SYMBOL(bitmap_copy_le);
#endif
unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags)
{
return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long),

17
lib/cpumask.c
View File

@ -14,7 +14,7 @@
* @start: the start point of the iteration
* @wrap: assume @n crossing @start terminates the iteration
*
* Returns >= nr_cpu_ids on completion
* Return: >= nr_cpu_ids on completion
*
* Note: the @wrap argument is required for the start condition when
* we cannot assume @start is set in @mask.
@ -48,8 +48,9 @@ EXPORT_SYMBOL(cpumask_next_wrap);
* @node: memory node from which to allocate or %NUMA_NO_NODE
*
* Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
* a nop returning a constant 1 (in <linux/cpumask.h>)
* Returns TRUE if memory allocation succeeded, FALSE otherwise.
* a nop returning a constant 1 (in <linux/cpumask.h>).
*
* Return: TRUE if memory allocation succeeded, FALSE otherwise.
*
* In addition, mask will be NULL if this fails. Note that gcc is
* usually smart enough to know that mask can never be NULL if
@ -115,7 +116,7 @@ void __init free_bootmem_cpumask_var(cpumask_var_t mask)
* @i: index number
* @node: local numa_node
*
* Returns online CPU according to a numa aware policy; local cpus are returned
* Return: online CPU according to a numa aware policy; local cpus are returned
* first, followed by non-local ones, then it wraps around.
*
* For those who wants to enumerate all CPUs based on their NUMA distances,
@ -163,7 +164,7 @@ static DEFINE_PER_CPU(int, distribute_cpu_mask_prev);
* Iterated calls using the same srcp1 and srcp2 will be distributed within
* their intersection.
*
* Returns >= nr_cpu_ids if the intersection is empty.
* Return: >= nr_cpu_ids if the intersection is empty.
*/
unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
const struct cpumask *src2p)
@ -182,6 +183,12 @@ unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
}
EXPORT_SYMBOL(cpumask_any_and_distribute);
/**
* cpumask_any_distribute - Return an arbitrary cpu from srcp
* @srcp: &cpumask for selection
*
* Return: >= nr_cpu_ids if the intersection is empty.
*/
unsigned int cpumask_any_distribute(const struct cpumask *srcp)
{
unsigned int next, prev;

24
lib/test_bitmap.c
View File

@ -330,6 +330,29 @@ static void __init test_copy(void)
expect_eq_pbl("0-108,128-1023", bmap2, 1024);
}
static void __init test_bitmap_region(void)
{
int pos, order;
DECLARE_BITMAP(bmap, 1000);
bitmap_zero(bmap, 1000);
for (order = 0; order < 10; order++) {
pos = bitmap_find_free_region(bmap, 1000, order);
if (order == 0)
expect_eq_uint(pos, 0);
else
expect_eq_uint(pos, order < 9 ? BIT(order) : -ENOMEM);
}
bitmap_release_region(bmap, 0, 0);
for (order = 1; order < 9; order++)
bitmap_release_region(bmap, BIT(order), order);
expect_eq_uint(bitmap_weight(bmap, 1000), 0);
}
#define EXP2_IN_BITS (sizeof(exp2) * 8)
static void __init test_replace(void)
@ -1227,6 +1250,7 @@ static void __init selftest(void)
test_zero_clear();
test_fill_set();
test_copy();
test_bitmap_region();
test_replace();
test_bitmap_arr32();
test_bitmap_arr64();