summaryrefslogtreecommitdiffstats
path: root/include/asm-generic/atomic.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
commit3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch)
treeb767d7f6e26bc64334d3f14f8422d187239dc45d /include/asm-generic/atomic.h
downloadlinux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz
linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'include/asm-generic/atomic.h')
-rw-r--r--include/asm-generic/atomic.h133
1 files changed, 133 insertions, 0 deletions
diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
new file mode 100644
index 000000000..22142c71d
--- /dev/null
+++ b/include/asm-generic/atomic.h
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Generic C implementation of atomic counter operations. Do not include in
+ * machine independent code.
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+#ifndef __ASM_GENERIC_ATOMIC_H
+#define __ASM_GENERIC_ATOMIC_H
+
+#include <asm/cmpxchg.h>
+#include <asm/barrier.h>
+
+#ifdef CONFIG_SMP
+
+/* we can build all atomic primitives from cmpxchg */
+
+#define ATOMIC_OP(op, c_op) \
+static inline void generic_atomic_##op(int i, atomic_t *v) \
+{ \
+ int c, old; \
+ \
+ c = v->counter; \
+ while ((old = arch_cmpxchg(&v->counter, c, c c_op i)) != c) \
+ c = old; \
+}
+
+#define ATOMIC_OP_RETURN(op, c_op) \
+static inline int generic_atomic_##op##_return(int i, atomic_t *v) \
+{ \
+ int c, old; \
+ \
+ c = v->counter; \
+ while ((old = arch_cmpxchg(&v->counter, c, c c_op i)) != c) \
+ c = old; \
+ \
+ return c c_op i; \
+}
+
+#define ATOMIC_FETCH_OP(op, c_op) \
+static inline int generic_atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ int c, old; \
+ \
+ c = v->counter; \
+ while ((old = arch_cmpxchg(&v->counter, c, c c_op i)) != c) \
+ c = old; \
+ \
+ return c; \
+}
+
+#else
+
+#include <linux/irqflags.h>
+
+#define ATOMIC_OP(op, c_op) \
+static inline void generic_atomic_##op(int i, atomic_t *v) \
+{ \
+ unsigned long flags; \
+ \
+ raw_local_irq_save(flags); \
+ v->counter = v->counter c_op i; \
+ raw_local_irq_restore(flags); \
+}
+
+#define ATOMIC_OP_RETURN(op, c_op) \
+static inline int generic_atomic_##op##_return(int i, atomic_t *v) \
+{ \
+ unsigned long flags; \
+ int ret; \
+ \
+ raw_local_irq_save(flags); \
+ ret = (v->counter = v->counter c_op i); \
+ raw_local_irq_restore(flags); \
+ \
+ return ret; \
+}
+
+#define ATOMIC_FETCH_OP(op, c_op) \
+static inline int generic_atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ unsigned long flags; \
+ int ret; \
+ \
+ raw_local_irq_save(flags); \
+ ret = v->counter; \
+ v->counter = v->counter c_op i; \
+ raw_local_irq_restore(flags); \
+ \
+ return ret; \
+}
+
+#endif /* CONFIG_SMP */
+
+ATOMIC_OP_RETURN(add, +)
+ATOMIC_OP_RETURN(sub, -)
+
+ATOMIC_FETCH_OP(add, +)
+ATOMIC_FETCH_OP(sub, -)
+ATOMIC_FETCH_OP(and, &)
+ATOMIC_FETCH_OP(or, |)
+ATOMIC_FETCH_OP(xor, ^)
+
+ATOMIC_OP(add, +)
+ATOMIC_OP(sub, -)
+ATOMIC_OP(and, &)
+ATOMIC_OP(or, |)
+ATOMIC_OP(xor, ^)
+
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+#define arch_atomic_add_return generic_atomic_add_return
+#define arch_atomic_sub_return generic_atomic_sub_return
+
+#define arch_atomic_fetch_add generic_atomic_fetch_add
+#define arch_atomic_fetch_sub generic_atomic_fetch_sub
+#define arch_atomic_fetch_and generic_atomic_fetch_and
+#define arch_atomic_fetch_or generic_atomic_fetch_or
+#define arch_atomic_fetch_xor generic_atomic_fetch_xor
+
+#define arch_atomic_add generic_atomic_add
+#define arch_atomic_sub generic_atomic_sub
+#define arch_atomic_and generic_atomic_and
+#define arch_atomic_or generic_atomic_or
+#define arch_atomic_xor generic_atomic_xor
+
+#define arch_atomic_read(v) READ_ONCE((v)->counter)
+#define arch_atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
+
+#endif /* __ASM_GENERIC_ATOMIC_H */