Date:   Fri, 27 Jan 2023 11:41:02 -0800
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Subject: [PATCH v2 25/33] mm: add FAULT_FLAG_VMA_LOCK flag
From:   Suren Baghdasaryan <surenb@google.com>
To:     akpm@linux-foundation.org
Cc:     michel@lespinasse.org, jglisse@google.com, mhocko@suse.com,
        vbabka@suse.cz, hannes@cmpxchg.org, mgorman@techsingularity.net,
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        linuxppc-dev@lists.ozlabs.org, x86@kernel.org,
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        surenb@google.com, Laurent Dufour <laurent.dufour@fr.ibm.com>
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Precedence: bulk

Add a new flag to distinguish page faults handled under protection of
per-vma lock.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Laurent Dufour <laurent.dufour@fr.ibm.com>
---
 include/linux/mm.h       | 3 ++-
 include/linux/mm_types.h | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index fa2b9d6e665e..a6de58bb40c7 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -472,7 +472,8 @@ static inline bool fault_flag_allow_retry_first(enum fault_flag flags)
 	{ FAULT_FLAG_USER,		"USER" }, \
 	{ FAULT_FLAG_REMOTE,		"REMOTE" }, \
 	{ FAULT_FLAG_INSTRUCTION,	"INSTRUCTION" }, \
-	{ FAULT_FLAG_INTERRUPTIBLE,	"INTERRUPTIBLE" }
+	{ FAULT_FLAG_INTERRUPTIBLE,	"INTERRUPTIBLE" }, \
+	{ FAULT_FLAG_VMA_LOCK,		"VMA_LOCK" }
 
 /*
  * vm_fault is filled by the pagefault handler and passed to the vma's
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 88619c6a29a3..c4c43f10344a 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -1053,6 +1053,7 @@ enum fault_flag {
 	FAULT_FLAG_INTERRUPTIBLE =	1 << 9,
 	FAULT_FLAG_UNSHARE =		1 << 10,
 	FAULT_FLAG_ORIG_PTE_VALID =	1 << 11,
+	FAULT_FLAG_VMA_LOCK =		1 << 12,
 };
 
 typedef unsigned int __bitwise zap_flags_t;
-- 
2.39.1