kernel/linux.git/lib/kstrtox.c, branch v7.3-rc1

lib: kstrtox: add kstrtoudec64() and kstrtodec64()

2026-06-29T23:15:52+00:00

Add helpers that parses decimal numbers into 64-bit number, i.e., decimal point numbers with pre-defined scale are parsed into a 64-bit value (fixed precision). After the decimal point, digits beyond the specified scale are ignored. Signed-off-by: Rodrigo Alencar Reviewed-by: Andy Shevchenko Signed-off-by: Jonathan Cameron

lib: kstrtox: add initial value to _parse_integer_limit()

2026-06-29T23:15:51+00:00

Add init parameter to _parse_integer_limit() that defines an initial value for the accumulated result when parsing an 64-bit integer. The new function prototype is adjusted so that the _parse_integer() macros stay consistent allowing for one more argument, which defaults to 0. Signed-off-by: Rodrigo Alencar Reviewed-by: Andy Shevchenko Signed-off-by: Jonathan Cameron

lib: kstrtox: Make _parse_integer() take variadic arguments

2026-06-29T18:05:38+00:00

Instead of having different functions that just use default parameters, combine those to use variadic arguments, so the user may call it using the same name. Signed-off-by: Andy Shevchenko Acked-by: Petr Mladek Signed-off-by: Rodrigo Alencar Signed-off-by: Jonathan Cameron

lib: fix _parse_integer_limit() to handle overflow

2026-05-29T04:24:49+00:00

Patch series "lib and lib/cmdline enhancements", v11. This series is a merge of the recently posted [1] and [2]. The first one is intended to adjust '_parse_integer_limit()' and 'memparse()' to not ignore overflows, extend string to 64-bit integer conversion tests, add KUnit-based test for 'memparse()' and fix kernel-doc glitches found in lib/cmdline.c. The second one was originated from RISCV-specific build fixes needed to integrate the former and now aims to provide platform-specific double-word shifts and corresponding KUnit test. Getting feedback from RISCV core maintainers would be very helpful. Special thanks to Andy Shevchenko, Charlie Jenkins, and Andrew Morton. This patch (of 8): In '_parse_integer_limit()', adjust native integer arithmetic with near-to-overflow branch where 'check_mul_overflow()' and 'check_add_overflow()' are used to check whether an intermediate result goes out of range, and denote such a case with ULLONG_MAX, thus making the function more similar to standard C library's 'strtoull()'. Adjust comment to kernel-doc style as well. Link: https://lore.kernel.org/20260519172259.908980-1-dmantipov@yandex.ru Link: https://lore.kernel.org/20260519172259.908980-2-dmantipov@yandex.ru Link: https://lore.kernel.org/linux-riscv/20260403103338.1122415-1-dmantipov@yandex.ru [1] Link: https://lore.kernel.org/linux-riscv/20260427090105.705529-1-dmantipov@yandex.ru [2] Signed-off-by: Dmitry Antipov Reviewed-by: Andy Shevchenko Cc: Albert Ou Cc: Alexandre Ghiti Cc: Andriy Shevchenko Cc: Ard Biesheuvel Cc: Palmer Dabbelt Cc: Charlie Jenkins Signed-off-by: Andrew Morton

lib/kstrtox: fix kstrtobool() docstring to mention enabled/disabled

2026-01-27T03:07:10+00:00

Commit ae5b3500856f ("kstrtox: add support for enabled and disabled in kstrtobool()") added support for 'e'/'E' (enabled) and 'd'/'D' (disabled) inputs, but did not update the docstring accordingly. Update the docstring to include 'Ee' (for true) and 'Dd' (for false) in the list of accepted first characters. Link: https://lkml.kernel.org/r/20251227092229.57330-1-chaitanyamishra.ai@gmail.com Fixes: ae5b3500856f ("kstrtox: add support for enabled and disabled in kstrtobool()") Signed-off-by: Chaitanya Mishra Cc: Mario Limonciello Signed-off-by: Andrew Morton

kstrtox: add support for enabled and disabled in kstrtobool()

2025-05-12T00:54:06+00:00

In some places in the kernel there is a design pattern for sysfs attributes to use kstrtobool() in store() and str_enabled_disabled() in show(). This is counterintuitive to interact with because kstrtobool() takes on/off but str_enabled_disabled() shows enabled/disabled. Some of those sysfs uses could switch to str_on_off() but for some attributes enabled/disabled really makes more sense. Add support for kstrtobool() to accept enabled/disabled. Link: https://lkml.kernel.org/r/20250321022538.1532445-1-superm1@kernel.org Signed-off-by: Mario Limonciello Signed-off-by: Andrew Morton

kstrtox: consistently use _tolower()

2023-08-21T20:46:25+00:00

We already use _tolower() in other places, so convert the one which open codes it. Link: https://lkml.kernel.org/r/20230817145919.543251-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko Signed-off-by: Andrew Morton

lib/kstrtox.c: add "false"/"true" support to kstrtobool()

2022-05-13T14:20:13+00:00

At many places in kernel, It is necessary to convert sysfs input to corresponding bool value e.g. "false" or "0" need to be converted to bool false, "true" or "1" need to be converted to bool true, places where such conversion is needed currently check the input string manually, kstrtobool() can be utilized at such places but currently it doesn't have support to accept "false"/"true". Add support to accept "false"/"true" as valid string in kstrtobool(). [akpm@linux-foundation.org: undo s/iff/if/, per Matthew] Link: https://lkml.kernel.org/r/20220426180203.70782-1-jvgediya@linux.ibm.com Signed-off-by: Jagdish Gediya Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: Andy Shevchenko Cc: "Huang, Ying" Cc: Dave Hansen Cc: Jonathan Cameron Cc: Alexey Dobriyan Cc: Richard Fitzgerald Cc: Petr Mladek Signed-off-by: Andrew Morton

kstrtox: uninline everything

2022-01-20T06:52:53+00:00

I've made a mistake of looking into lib/kstrtox.o code generation. The only function remotely performance critical is _parse_integer() (via /proc/*/map_files/*), everything else is not. Uninline everything, shrink lib/kstrtox.o by ~20 % ! Space savings on x86_64: add/remove: 0/0 grow/shrink: 0/23 up/down: 0/-1269 (-1269 !!!) Function old new delta kstrtoull 16 13 -3 kstrtouint 59 48 -11 kstrtou8 60 49 -11 kstrtou16 61 50 -11 _kstrtoul 46 35 -11 kstrtoull_from_user 95 83 -12 kstrtoul_from_user 95 83 -12 kstrtoll 93 80 -13 kstrtouint_from_user 124 83 -41 kstrtou8_from_user 125 83 -42 kstrtou16_from_user 126 83 -43 kstrtos8 101 50 -51 kstrtos16 102 51 -51 kstrtoint 100 49 -51 _kstrtol 93 35 -58 kstrtobool_from_user 156 75 -81 kstrtoll_from_user 165 83 -82 kstrtol_from_user 165 83 -82 kstrtoint_from_user 172 83 -89 kstrtos8_from_user 173 83 -90 kstrtos16_from_user 174 83 -91 _parse_integer 136 10 -126 _kstrtoull 308 101 -207 Total: Before=3421236, After=3419967, chg -0.04% Link: https://lkml.kernel.org/r/YZDsFDhHst4m2Pnt@localhost.localdomain Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'akpm' (patches from Andrew)

2021-07-02T19:08:10+00:00

Merge more updates from Andrew Morton: "190 patches. Subsystems affected by this patch series: mm (hugetlb, userfaultfd, vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock, migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap, zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc, core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs, signals, exec, kcov, selftests, compress/decompress, and ipc" * emailed patches from Andrew Morton : (190 commits) ipc/util.c: use binary search for max_idx ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock ipc: use kmalloc for msg_queue and shmid_kernel ipc sem: use kvmalloc for sem_undo allocation lib/decompressors: remove set but not used variabled 'level' selftests/vm/pkeys: exercise x86 XSAVE init state selftests/vm/pkeys: refill shadow register after implicit kernel write selftests/vm/pkeys: handle negative sys_pkey_alloc() return code selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random kcov: add __no_sanitize_coverage to fix noinstr for all architectures exec: remove checks in __register_bimfmt() x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned hfsplus: report create_date to kstat.btime hfsplus: remove unnecessary oom message nilfs2: remove redundant continue statement in a while-loop kprobes: remove duplicated strong free_insn_page in x86 and s390 init: print out unknown kernel parameters checkpatch: do not complain about positive return values starting with EPOLL checkpatch: improve the indented label test checkpatch: scripts/spdxcheck.py now requires python3 ...