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| author | Dapeng Mi <dapeng1.mi@linux.intel.com> | 2026-09-17 09:52:33 +0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2026-09-22 11:37:46 +0200 |
| commit | 0102c8c7fdfc4bd700971daff2b94470f4eafae4 (patch) | |
| tree | 531306c2299f9a269f0a986e29f17ba972180104 /lib/devmem_is_allowed.c | |
| download | linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.tar.gz linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.zip | |
perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted
DMR introduces Offmodule Response events in place of the legacy
Offcore Response events, but it still exposes the inherited
offcore_rsp PMU attribute for programming the corresponding MSR data.
Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface
matches the underlying event name and avoids user & tooling confusion.
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com
Diffstat (limited to 'lib/devmem_is_allowed.c')
| -rw-r--r-- | lib/devmem_is_allowed.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/lib/devmem_is_allowed.c b/lib/devmem_is_allowed.c new file mode 100644 index 000000000..9c060c69f --- /dev/null +++ b/lib/devmem_is_allowed.c @@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * A generic version of devmem_is_allowed. + * + * Based on arch/arm64/mm/mmap.c + * + * Copyright (C) 2020 Google, Inc. + * Copyright (C) 2012 ARM Ltd. + */ + +#include <linux/mm.h> +#include <linux/ioport.h> +#include <linux/io.h> + +/* + * devmem_is_allowed() checks to see if /dev/mem access to a certain address + * is valid. The argument is a physical page number. We mimic x86 here by + * disallowing access to system RAM as well as device-exclusive MMIO regions. + * This effectively disable read()/write() on /dev/mem. + */ +int devmem_is_allowed(unsigned long pfn) +{ + if (iomem_is_exclusive(PFN_PHYS(pfn))) + return 0; + if (!page_is_ram(pfn)) + return 1; + return 0; +} |
