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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /include/asm-generic/futex.h
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'include/asm-generic/futex.h')
-rw-r--r--include/asm-generic/futex.h123
1 files changed, 123 insertions, 0 deletions
diff --git a/include/asm-generic/futex.h b/include/asm-generic/futex.h
new file mode 100644
index 000000000..fbbcfd801
--- /dev/null
+++ b/include/asm-generic/futex.h
@@ -0,0 +1,123 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_GENERIC_FUTEX_H
+#define _ASM_GENERIC_FUTEX_H
+
+#include <linux/futex.h>
+#include <linux/uaccess.h>
+#include <asm/errno.h>
+
+#ifndef futex_atomic_cmpxchg_inatomic
+#ifndef CONFIG_SMP
+/*
+ * The following implementation only for uniprocessor machines.
+ * It relies on preempt_disable() ensuring mutual exclusion.
+ *
+ */
+#define futex_atomic_cmpxchg_inatomic(uval, uaddr, oldval, newval) \
+ futex_atomic_cmpxchg_inatomic_local(uval, uaddr, oldval, newval)
+#define arch_futex_atomic_op_inuser(op, oparg, oval, uaddr) \
+ futex_atomic_op_inuser_local(op, oparg, oval, uaddr)
+#endif /* CONFIG_SMP */
+#endif
+
+/**
+ * futex_atomic_op_inuser_local() - Atomic arithmetic operation with constant
+ * argument and comparison of the previous
+ * futex value with another constant.
+ *
+ * @op: operation to execute
+ * @oparg: argument of the operation
+ * @oval: previous value at @uaddr on successful return
+ * @uaddr: pointer to user space address
+ *
+ * Return:
+ * 0 - On success
+ * -EFAULT - User access resulted in a page fault
+ * -EAGAIN - Atomic operation was unable to complete due to contention
+ * -ENOSYS - Operation not supported
+ */
+static inline int
+futex_atomic_op_inuser_local(int op, u32 oparg, int *oval, u32 __user *uaddr)
+{
+ int oldval, ret;
+ u32 tmp;
+
+ preempt_disable();
+
+ ret = -EFAULT;
+ if (unlikely(get_user(oldval, uaddr) != 0))
+ goto out_pagefault_enable;
+
+ ret = 0;
+ tmp = oldval;
+
+ switch (op) {
+ case FUTEX_OP_SET:
+ tmp = oparg;
+ break;
+ case FUTEX_OP_ADD:
+ tmp += oparg;
+ break;
+ case FUTEX_OP_OR:
+ tmp |= oparg;
+ break;
+ case FUTEX_OP_ANDN:
+ tmp &= ~oparg;
+ break;
+ case FUTEX_OP_XOR:
+ tmp ^= oparg;
+ break;
+ default:
+ ret = -ENOSYS;
+ }
+
+ if (ret == 0 && unlikely(put_user(tmp, uaddr) != 0))
+ ret = -EFAULT;
+
+out_pagefault_enable:
+ preempt_enable();
+
+ if (ret == 0)
+ *oval = oldval;
+
+ return ret;
+}
+
+/**
+ * futex_atomic_cmpxchg_inatomic_local() - Compare and exchange the content of the
+ * uaddr with newval if the current value is
+ * oldval.
+ * @uval: pointer to store content of @uaddr
+ * @uaddr: pointer to user space address
+ * @oldval: old value
+ * @newval: new value to store to @uaddr
+ *
+ * Return:
+ * 0 - On success
+ * -EFAULT - User access resulted in a page fault
+ * -EAGAIN - Atomic operation was unable to complete due to contention
+ */
+static inline int
+futex_atomic_cmpxchg_inatomic_local(u32 *uval, u32 __user *uaddr,
+ u32 oldval, u32 newval)
+{
+ u32 val;
+
+ preempt_disable();
+ if (unlikely(get_user(val, uaddr) != 0)) {
+ preempt_enable();
+ return -EFAULT;
+ }
+
+ if (val == oldval && unlikely(put_user(newval, uaddr) != 0)) {
+ preempt_enable();
+ return -EFAULT;
+ }
+
+ *uval = val;
+ preempt_enable();
+
+ return 0;
+}
+
+#endif