Commit 55324e46 authored by Suren Baghdasaryan's avatar Suren Baghdasaryan Committed by Andrew Morton
Browse files

mm: add FAULT_FLAG_VMA_LOCK flag 

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

[surenb@google.com: document FAULT_FLAG_VMA_LOCK flag]
  Link: https://lkml.kernel.org/r/20230301022720.1380780-2-surenb@google.com
  Link: https://lore.kernel.org/all/20230301113648.7c279865@canb.auug.org.au/
Link: https://lkml.kernel.org/r/20230227173632.3292573-26-surenb@google.com


Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
Reviewed-by: default avatarLaurent Dufour <laurent.dufour@fr.ibm.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 2ac0af1b

include/linux/mm.h

+2 −1
Original line number Diff line number Diff line
@@ -479,7 +479,8 @@ 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

include/linux/mm_types.h

+2 −0
Original line number Diff line number Diff line
@@ -1049,6 +1049,7 @@ typedef struct { 
 *                      mapped after the fault.

 * @FAULT_FLAG_ORIG_PTE_VALID: whether the fault has vmf->orig_pte cached.

 *                        We should only access orig_pte if this flag set.

 * @FAULT_FLAG_VMA_LOCK: The fault is handled under VMA lock.

 *

 * About @FAULT_FLAG_ALLOW_RETRY and @FAULT_FLAG_TRIED: we can specify

 * whether we would allow page faults to retry by specifying these two
@@ -1086,6 +1087,7 @@ 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;