From 4beba9486abd2f86d125271d6946f7c38ed0fe77 Mon Sep 17 00:00:00 2001 From: Steven Price Date: Wed, 22 Apr 2020 15:25:27 +0100 Subject: [PATCH] mm: Add PG_arch_2 page flag For arm64 MTE support it is necessary to be able to mark pages that contain user space visible tags that will need to be saved/restored e.g. when swapped out. To support this add a new arch specific flag (PG_arch_2). This flag is only available on 64-bit architectures due to the limited number of spare page flags on the 32-bit ones. Signed-off-by: Steven Price [catalin.marinas@arm.com: use CONFIG_64BIT for guarding this new flag] Signed-off-by: Catalin Marinas Cc: Andrew Morton --- fs/proc/page.c | 3 +++ include/linux/kernel-page-flags.h | 1 + include/linux/page-flags.h | 3 +++ include/trace/events/mmflags.h | 9 ++++++++- tools/vm/page-types.c | 2 ++ 5 files changed, 17 insertions(+), 1 deletion(-) diff --git a/fs/proc/page.c b/fs/proc/page.c index f909243d4a66..9f1077d94cde 100644 --- a/fs/proc/page.c +++ b/fs/proc/page.c @@ -217,6 +217,9 @@ u64 stable_page_flags(struct page *page) u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2); u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1); u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1); +#ifdef CONFIG_64BIT + u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_2); +#endif return u; }; diff --git a/include/linux/kernel-page-flags.h b/include/linux/kernel-page-flags.h index abd20ef93c98..eee1877a354e 100644 --- a/include/linux/kernel-page-flags.h +++ b/include/linux/kernel-page-flags.h @@ -17,5 +17,6 @@ #define KPF_ARCH 38 #define KPF_UNCACHED 39 #define KPF_SOFTDIRTY 40 +#define KPF_ARCH_2 41 #endif /* LINUX_KERNEL_PAGE_FLAGS_H */ diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 6be1aa559b1e..276140c94f4a 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -135,6 +135,9 @@ enum pageflags { #if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT) PG_young, PG_idle, +#endif +#ifdef CONFIG_64BIT + PG_arch_2, #endif __NR_PAGEFLAGS, diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h index 5fb752034386..67018d367b9f 100644 --- a/include/trace/events/mmflags.h +++ b/include/trace/events/mmflags.h @@ -79,6 +79,12 @@ #define IF_HAVE_PG_IDLE(flag,string) #endif +#ifdef CONFIG_64BIT +#define IF_HAVE_PG_ARCH_2(flag,string) ,{1UL << flag, string} +#else +#define IF_HAVE_PG_ARCH_2(flag,string) +#endif + #define __def_pageflag_names \ {1UL << PG_locked, "locked" }, \ {1UL << PG_waiters, "waiters" }, \ @@ -105,7 +111,8 @@ IF_HAVE_PG_MLOCK(PG_mlocked, "mlocked" ) \ IF_HAVE_PG_UNCACHED(PG_uncached, "uncached" ) \ IF_HAVE_PG_HWPOISON(PG_hwpoison, "hwpoison" ) \ IF_HAVE_PG_IDLE(PG_young, "young" ) \ -IF_HAVE_PG_IDLE(PG_idle, "idle" ) +IF_HAVE_PG_IDLE(PG_idle, "idle" ) \ +IF_HAVE_PG_ARCH_2(PG_arch_2, "arch_2" ) #define show_page_flags(flags) \ (flags) ? __print_flags(flags, "|", \ diff --git a/tools/vm/page-types.c b/tools/vm/page-types.c index 58c0eab71bca..0517c744b04e 100644 --- a/tools/vm/page-types.c +++ b/tools/vm/page-types.c @@ -78,6 +78,7 @@ #define KPF_ARCH 38 #define KPF_UNCACHED 39 #define KPF_SOFTDIRTY 40 +#define KPF_ARCH_2 41 /* [48-] take some arbitrary free slots for expanding overloaded flags * not part of kernel API @@ -135,6 +136,7 @@ static const char * const page_flag_names[] = { [KPF_ARCH] = "h:arch", [KPF_UNCACHED] = "c:uncached", [KPF_SOFTDIRTY] = "f:softdirty", + [KPF_ARCH_2] = "H:arch_2", [KPF_READAHEAD] = "I:readahead", [KPF_SLOB_FREE] = "P:slob_free",