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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /arch/arm/lib/findbit.S
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'arch/arm/lib/findbit.S')
-rw-r--r--arch/arm/lib/findbit.S139
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diff --git a/arch/arm/lib/findbit.S b/arch/arm/lib/findbit.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/arch/arm/lib/findbit.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ *
+ * 16th March 2001 - John Ripley <jripley@sonicblue.com>
+ * Fixed so that "size" is an exclusive not an inclusive quantity.
+ * All users of these functions expect exclusive sizes, and may
+ * also call with zero size.
+ * Reworked by rmk.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/unwind.h>
+ .text
+
+#ifdef __ARMEB__
+#define SWAB_ENDIAN le
+#else
+#define SWAB_ENDIAN be
+#endif
+
+ .macro find_first, endian, set, name
+ENTRY(_find_first_\name\()bit_\endian)
+ UNWIND( .fnstart)
+ teq r1, #0
+ beq 3f
+ mov r2, #0
+1: ldr r3, [r0], #4
+ .ifeq \set
+ mvns r3, r3 @ invert/test bits
+ .else
+ movs r3, r3 @ test bits
+ .endif
+ .ifc \endian, SWAB_ENDIAN
+ bne .L_found_swab
+ .else
+ bne .L_found @ found the bit?
+ .endif
+ add r2, r2, #32 @ next index
+2: cmp r2, r1 @ any more?
+ blo 1b
+3: mov r0, r1 @ no more bits
+ ret lr
+ UNWIND( .fnend)
+ENDPROC(_find_first_\name\()bit_\endian)
+ .endm
+
+ .macro find_next, endian, set, name
+ENTRY(_find_next_\name\()bit_\endian)
+ UNWIND( .fnstart)
+ cmp r2, r1
+ bhs 3b
+ mov ip, r2, lsr #5 @ word index
+ add r0, r0, ip, lsl #2
+ ands ip, r2, #31 @ bit position
+ beq 1b
+ ldr r3, [r0], #4
+ .ifeq \set
+ mvn r3, r3 @ invert bits
+ .endif
+ .ifc \endian, SWAB_ENDIAN
+ rev_l r3, ip
+ .if .Lrev_l_uses_tmp
+ @ we need to recompute ip because rev_l will have overwritten
+ @ it.
+ and ip, r2, #31 @ bit position
+ .endif
+ .endif
+ movs r3, r3, lsr ip @ shift off unused bits
+ bne .L_found
+ orr r2, r2, #31 @ no zero bits
+ add r2, r2, #1 @ align bit pointer
+ b 2b @ loop for next bit
+ UNWIND( .fnend)
+ENDPROC(_find_next_\name\()bit_\endian)
+ .endm
+
+ .macro find_bit, endian, set, name
+ find_first \endian, \set, \name
+ find_next \endian, \set, \name
+ .endm
+
+/* _find_first_zero_bit_le and _find_next_zero_bit_le */
+ find_bit le, 0, zero_
+
+/* _find_first_bit_le and _find_next_bit_le */
+ find_bit le, 1
+
+#ifdef __ARMEB__
+
+/* _find_first_zero_bit_be and _find_next_zero_bit_be */
+ find_bit be, 0, zero_
+
+/* _find_first_bit_be and _find_next_bit_be */
+ find_bit be, 1
+
+#endif
+
+/*
+ * One or more bits in the LSB of r3 are assumed to be set.
+ */
+.L_found_swab:
+ UNWIND( .fnstart)
+ rev_l r3, ip
+.L_found:
+#if __LINUX_ARM_ARCH__ >= 7
+ rbit r3, r3 @ reverse bits
+ clz r3, r3 @ count high zero bits
+ add r0, r2, r3 @ add offset of first set bit
+#elif __LINUX_ARM_ARCH__ >= 5
+ rsb r0, r3, #0
+ and r3, r3, r0 @ mask out lowest bit set
+ clz r3, r3 @ count high zero bits
+ rsb r3, r3, #31 @ offset of first set bit
+ add r0, r2, r3 @ add offset of first set bit
+#else
+ mov ip, #~0
+ tst r3, ip, lsr #16 @ test bits 0-15
+ addeq r2, r2, #16
+ moveq r3, r3, lsr #16
+ tst r3, #0x00ff
+ addeq r2, r2, #8
+ moveq r3, r3, lsr #8
+ tst r3, #0x000f
+ addeq r2, r2, #4
+ moveq r3, r3, lsr #4
+ tst r3, #0x0003
+ addeq r2, r2, #2
+ moveq r3, r3, lsr #2
+ tst r3, #0x0001
+ addeq r2, r2, #1
+ mov r0, r2
+#endif
+ cmp r1, r0 @ Clamp to maxbit
+ movlo r0, r1
+ ret lr
+ UNWIND( .fnend)