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+.\" Copyright (C) 1994, 1995, Daniel Quinlan <quinlan@yggdrasil.com>
+.\" Copyright (C) 2002-2008, 2017, Michael Kerrisk <mtk.manpages@gmail.com>
+.\" Copyright (C) 2023, Alejandro Colomar <alx@kernel.org>
+.\"
+.\" SPDX-License-Identifier: GPL-3.0-or-later
+.\"
+.TH proc_pid_pagemap 5 2023-08-15 "Linux man-pages 6.7"
+.SH NAME
+/proc/pid/pagemap \- mapping of virtual pages
+.SH DESCRIPTION
+.TP
+.IR /proc/ pid /pagemap " (since Linux 2.6.25)"
+This file shows the mapping of each of the process's virtual pages
+into physical page frames or swap area.
+It contains one 64-bit value for each virtual page,
+with the bits set as follows:
+.RS
+.TP
+63
+If set, the page is present in RAM.
+.TP
+62
+If set, the page is in swap space
+.TP
+61 (since Linux 3.5)
+The page is a file-mapped page or a shared anonymous page.
+.TP
+60\[en]58 (since Linux 3.11)
+Zero
+.\" Not quite true; see commit 541c237c0923f567c9c4cabb8a81635baadc713f
+.TP
+57 (since Linux 5.14)
+If set, the page is write-protected through
+.BR userfaultfd (2).
+.TP
+56 (since Linux 4.2)
+.\" commit 77bb499bb60f4b79cca7d139c8041662860fcf87
+.\" commit 83b4b0bb635eee2b8e075062e4e008d1bc110ed7
+The page is exclusively mapped.
+.TP
+55 (since Linux 3.11)
+PTE is soft-dirty
+(see the kernel source file
+.IR Documentation/admin\-guide/mm/soft\-dirty.rst ).
+.TP
+54\[en]0
+If the page is present in RAM (bit 63), then these bits
+provide the page frame number, which can be used to index
+.I /proc/kpageflags
+and
+.IR /proc/kpagecount .
+If the page is present in swap (bit 62),
+then bits 4\[en]0 give the swap type, and bits 54\[en]5 encode the swap offset.
+.RE
+.IP
+Before Linux 3.11, bits 60\[en]55 were
+used to encode the base-2 log of the page size.
+.IP
+To employ
+.IR /proc/ pid /pagemap
+efficiently, use
+.IR /proc/ pid /maps
+to determine which areas of memory are actually mapped and seek
+to skip over unmapped regions.
+.IP
+The
+.IR /proc/ pid /pagemap
+file is present only if the
+.B CONFIG_PROC_PAGE_MONITOR
+kernel configuration option is enabled.
+.IP
+Permission to access this file is governed by a ptrace access mode
+.B PTRACE_MODE_READ_FSCREDS
+check; see
+.BR ptrace (2).
+.SH SEE ALSO
+.BR proc (5)