Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 1396 insertions, 0 deletions

diff --git a/tools/vm/page-types.c b/tools/vm/page-types.c
new file mode 100644
index 000000000..381dcc00c
--- /dev/null
+++ b/tools/vm/page-types.c
@@ -0,0 +1,1396 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * page-types: Tool for querying page flags
+ *
+ * Copyright (C) 2009 Intel corporation
+ *
+ * Authors: Wu Fengguang <fengguang.wu@intel.com>
+ */
+
+#define _FILE_OFFSET_BITS 64
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <stdarg.h>
+#include <string.h>
+#include <getopt.h>
+#include <limits.h>
+#include <assert.h>
+#include <ftw.h>
+#include <time.h>
+#include <setjmp.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/errno.h>
+#include <sys/fcntl.h>
+#include <sys/mount.h>
+#include <sys/statfs.h>
+#include <sys/mman.h>
+#include "../../include/uapi/linux/magic.h"
+#include "../../include/uapi/linux/kernel-page-flags.h"
+#include <api/fs/fs.h>
+
+#ifndef MAX_PATH
+# define MAX_PATH 256
+#endif
+
+#ifndef STR
+# define _STR(x) #x
+# define STR(x) _STR(x)
+#endif
+
+/*
+ * pagemap kernel ABI bits
+ */
+
+#define PM_ENTRY_BYTES		8
+#define PM_PFRAME_BITS		55
+#define PM_PFRAME_MASK		((1LL << PM_PFRAME_BITS) - 1)
+#define PM_PFRAME(x)		((x) & PM_PFRAME_MASK)
+#define MAX_SWAPFILES_SHIFT	5
+#define PM_SWAP_OFFSET(x)	(((x) & PM_PFRAME_MASK) >> MAX_SWAPFILES_SHIFT)
+#define PM_SOFT_DIRTY		(1ULL << 55)
+#define PM_MMAP_EXCLUSIVE	(1ULL << 56)
+#define PM_FILE			(1ULL << 61)
+#define PM_SWAP			(1ULL << 62)
+#define PM_PRESENT		(1ULL << 63)
+
+/*
+ * kernel page flags
+ */
+
+#define KPF_BYTES		8
+#define PROC_KPAGEFLAGS		"/proc/kpageflags"
+#define PROC_KPAGECOUNT		"/proc/kpagecount"
+#define PROC_KPAGECGROUP	"/proc/kpagecgroup"
+
+#define SYS_KERNEL_MM_PAGE_IDLE "/sys/kernel/mm/page_idle/bitmap"
+
+/* [32-] kernel hacking assistances */
+#define KPF_RESERVED		32
+#define KPF_MLOCKED		33
+#define KPF_MAPPEDTODISK	34
+#define KPF_PRIVATE		35
+#define KPF_PRIVATE_2		36
+#define KPF_OWNER_PRIVATE	37
+#define KPF_ARCH		38
+#define KPF_UNCACHED		39
+#define KPF_SOFTDIRTY		40
+#define KPF_ARCH_2		41
+
+/* [47-] take some arbitrary free slots for expanding overloaded flags
+ * not part of kernel API
+ */
+#define KPF_ANON_EXCLUSIVE	47
+#define KPF_READAHEAD		48
+#define KPF_SLOB_FREE		49
+#define KPF_SLUB_FROZEN		50
+#define KPF_SLUB_DEBUG		51
+#define KPF_FILE		61
+#define KPF_SWAP		62
+#define KPF_MMAP_EXCLUSIVE	63
+
+#define KPF_ALL_BITS		((uint64_t)~0ULL)
+#define KPF_HACKERS_BITS	(0xffffULL << 32)
+#define KPF_OVERLOADED_BITS	(0xffffULL << 48)
+#define BIT(name)		(1ULL << KPF_##name)
+#define BITS_COMPOUND		(BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
+
+static const char * const page_flag_names[] = {
+	[KPF_LOCKED]		= "L:locked",
+	[KPF_ERROR]		= "E:error",
+	[KPF_REFERENCED]	= "R:referenced",
+	[KPF_UPTODATE]		= "U:uptodate",
+	[KPF_DIRTY]		= "D:dirty",
+	[KPF_LRU]		= "l:lru",
+	[KPF_ACTIVE]		= "A:active",
+	[KPF_SLAB]		= "S:slab",
+	[KPF_WRITEBACK]		= "W:writeback",
+	[KPF_RECLAIM]		= "I:reclaim",
+	[KPF_BUDDY]		= "B:buddy",
+
+	[KPF_MMAP]		= "M:mmap",
+	[KPF_ANON]		= "a:anonymous",
+	[KPF_SWAPCACHE]		= "s:swapcache",
+	[KPF_SWAPBACKED]	= "b:swapbacked",
+	[KPF_COMPOUND_HEAD]	= "H:compound_head",
+	[KPF_COMPOUND_TAIL]	= "T:compound_tail",
+	[KPF_HUGE]		= "G:huge",
+	[KPF_UNEVICTABLE]	= "u:unevictable",
+	[KPF_HWPOISON]		= "X:hwpoison",
+	[KPF_NOPAGE]		= "n:nopage",
+	[KPF_KSM]		= "x:ksm",
+	[KPF_THP]		= "t:thp",
+	[KPF_OFFLINE]		= "o:offline",
+	[KPF_PGTABLE]		= "g:pgtable",
+	[KPF_ZERO_PAGE]		= "z:zero_page",
+	[KPF_IDLE]              = "i:idle_page",
+
+	[KPF_RESERVED]		= "r:reserved",
+	[KPF_MLOCKED]		= "m:mlocked",
+	[KPF_MAPPEDTODISK]	= "d:mappedtodisk",
+	[KPF_PRIVATE]		= "P:private",
+	[KPF_PRIVATE_2]		= "p:private_2",
+	[KPF_OWNER_PRIVATE]	= "O:owner_private",
+	[KPF_ARCH]		= "h:arch",
+	[KPF_UNCACHED]		= "c:uncached",
+	[KPF_SOFTDIRTY]		= "f:softdirty",
+	[KPF_ARCH_2]		= "H:arch_2",
+
+	[KPF_ANON_EXCLUSIVE]	= "d:anon_exclusive",
+	[KPF_READAHEAD]		= "I:readahead",
+	[KPF_SLOB_FREE]		= "P:slob_free",
+	[KPF_SLUB_FROZEN]	= "A:slub_frozen",
+	[KPF_SLUB_DEBUG]	= "E:slub_debug",
+
+	[KPF_FILE]		= "F:file",
+	[KPF_SWAP]		= "w:swap",
+	[KPF_MMAP_EXCLUSIVE]	= "1:mmap_exclusive",
+};
+
+
+/*
+ * data structures
+ */
+
+static int		opt_raw;	/* for kernel developers */
+static int		opt_list;	/* list pages (in ranges) */
+static int		opt_mark_idle;	/* set accessed bit */
+static int		opt_no_summary;	/* don't show summary */
+static pid_t		opt_pid;	/* process to walk */
+const char		*opt_file;	/* file or directory path */
+static uint64_t		opt_cgroup;	/* cgroup inode */
+static int		opt_list_cgroup;/* list page cgroup */
+static int		opt_list_mapcnt;/* list page map count */
+static const char	*opt_kpageflags;/* kpageflags file to parse */
+
+#define MAX_ADDR_RANGES	1024
+static int		nr_addr_ranges;
+static unsigned long	opt_offset[MAX_ADDR_RANGES];
+static unsigned long	opt_size[MAX_ADDR_RANGES];
+
+#define MAX_VMAS	10240
+static int		nr_vmas;
+static unsigned long	pg_start[MAX_VMAS];
+static unsigned long	pg_end[MAX_VMAS];
+
+#define MAX_BIT_FILTERS	64
+static int		nr_bit_filters;
+static uint64_t		opt_mask[MAX_BIT_FILTERS];
+static uint64_t		opt_bits[MAX_BIT_FILTERS];
+
+static int		page_size;
+
+static int		pagemap_fd;
+static int		kpageflags_fd;
+static int		kpagecount_fd = -1;
+static int		kpagecgroup_fd = -1;
+static int		page_idle_fd = -1;
+
+static int		opt_hwpoison;
+static int		opt_unpoison;
+
+static const char	*hwpoison_debug_fs;
+static int		hwpoison_inject_fd;
+static int		hwpoison_forget_fd;
+
+#define HASH_SHIFT	13
+#define HASH_SIZE	(1 << HASH_SHIFT)
+#define HASH_MASK	(HASH_SIZE - 1)
+#define HASH_KEY(flags)	(flags & HASH_MASK)
+
+static unsigned long	total_pages;
+static unsigned long	nr_pages[HASH_SIZE];
+static uint64_t		page_flags[HASH_SIZE];
+
+
+/*
+ * helper functions
+ */
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+
+#define min_t(type, x, y) ({			\
+	type __min1 = (x);			\
+	type __min2 = (y);			\
+	__min1 < __min2 ? __min1 : __min2; })
+
+#define max_t(type, x, y) ({			\
+	type __max1 = (x);			\
+	type __max2 = (y);			\
+	__max1 > __max2 ? __max1 : __max2; })
+
+static unsigned long pages2mb(unsigned long pages)
+{
+	return (pages * page_size) >> 20;
+}
+
+static void fatal(const char *x, ...)
+{
+	va_list ap;
+
+	va_start(ap, x);
+	vfprintf(stderr, x, ap);
+	va_end(ap);
+	exit(EXIT_FAILURE);
+}
+
+static int checked_open(const char *pathname, int flags)
+{
+	int fd = open(pathname, flags);
+
+	if (fd < 0) {
+		perror(pathname);
+		exit(EXIT_FAILURE);
+	}
+
+	return fd;
+}
+
+/*
+ * pagemap/kpageflags routines
+ */
+
+static unsigned long do_u64_read(int fd, const char *name,
+				 uint64_t *buf,
+				 unsigned long index,
+				 unsigned long count)
+{
+	long bytes;
+
+	if (index > ULONG_MAX / 8)
+		fatal("index overflow: %lu\n", index);
+
+	bytes = pread(fd, buf, count * 8, (off_t)index * 8);
+	if (bytes < 0) {
+		perror(name);
+		exit(EXIT_FAILURE);
+	}
+	if (bytes % 8)
+		fatal("partial read: %lu bytes\n", bytes);
+
+	return bytes / 8;
+}
+
+static unsigned long kpageflags_read(uint64_t *buf,
+				     unsigned long index,
+				     unsigned long pages)
+{
+	return do_u64_read(kpageflags_fd, opt_kpageflags, buf, index, pages);
+}
+
+static unsigned long kpagecgroup_read(uint64_t *buf,
+				      unsigned long index,
+				      unsigned long pages)
+{
+	if (kpagecgroup_fd < 0)
+		return pages;
+
+	return do_u64_read(kpagecgroup_fd, opt_kpageflags, buf, index, pages);
+}
+
+static unsigned long kpagecount_read(uint64_t *buf,
+				     unsigned long index,
+				     unsigned long pages)
+{
+	return kpagecount_fd < 0 ? pages :
+		do_u64_read(kpagecount_fd, PROC_KPAGECOUNT,
+			    buf, index, pages);
+}
+
+static unsigned long pagemap_read(uint64_t *buf,
+				  unsigned long index,
+				  unsigned long pages)
+{
+	return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
+}
+
+static unsigned long pagemap_pfn(uint64_t val)
+{
+	unsigned long pfn;
+
+	if (val & PM_PRESENT)
+		pfn = PM_PFRAME(val);
+	else
+		pfn = 0;
+
+	return pfn;
+}
+
+static unsigned long pagemap_swap_offset(uint64_t val)
+{
+	return val & PM_SWAP ? PM_SWAP_OFFSET(val) : 0;
+}
+
+/*
+ * page flag names
+ */
+
+static char *page_flag_name(uint64_t flags)
+{
+	static char buf[65];
+	int present;
+	size_t i, j;
+
+	for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
+		present = (flags >> i) & 1;
+		if (!page_flag_names[i]) {
+			if (present)
+				fatal("unknown flag bit %d\n", i);
+			continue;
+		}
+		buf[j++] = present ? page_flag_names[i][0] : '_';
+	}
+
+	return buf;
+}
+
+static char *page_flag_longname(uint64_t flags)
+{
+	static char buf[1024];
+	size_t i, n;
+
+	for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
+		if (!page_flag_names[i])
+			continue;
+		if ((flags >> i) & 1)
+			n += snprintf(buf + n, sizeof(buf) - n, "%s,",
+					page_flag_names[i] + 2);
+	}
+	if (n)
+		n--;
+	buf[n] = '\0';
+
+	return buf;
+}
+
+
+/*
+ * page list and summary
+ */
+
+static void show_page_range(unsigned long voffset, unsigned long offset,
+			    unsigned long size, uint64_t flags,
+			    uint64_t cgroup, uint64_t mapcnt)
+{
+	static uint64_t      flags0;
+	static uint64_t	     cgroup0;
+	static uint64_t      mapcnt0;
+	static unsigned long voff;
+	static unsigned long index;
+	static unsigned long count;
+
+	if (flags == flags0 && cgroup == cgroup0 && mapcnt == mapcnt0 &&
+	    offset == index + count && size && voffset == voff + count) {
+		count += size;
+		return;
+	}
+
+	if (count) {
+		if (opt_pid)
+			printf("%lx\t", voff);
+		if (opt_file)
+			printf("%lx\t", voff);
+		if (opt_list_cgroup)
+			printf("@%llu\t", (unsigned long long)cgroup0);
+		if (opt_list_mapcnt)
+			printf("%lu\t", mapcnt0);
+		printf("%lx\t%lx\t%s\n",
+				index, count, page_flag_name(flags0));
+	}
+
+	flags0 = flags;
+	cgroup0 = cgroup;
+	mapcnt0 = mapcnt;
+	index  = offset;
+	voff   = voffset;
+	count  = size;
+}
+
+static void flush_page_range(void)
+{
+	show_page_range(0, 0, 0, 0, 0, 0);
+}
+
+static void show_page(unsigned long voffset, unsigned long offset,
+		      uint64_t flags, uint64_t cgroup, uint64_t mapcnt)
+{
+	if (opt_pid)
+		printf("%lx\t", voffset);
+	if (opt_file)
+		printf("%lx\t", voffset);
+	if (opt_list_cgroup)
+		printf("@%llu\t", (unsigned long long)cgroup);
+	if (opt_list_mapcnt)
+		printf("%lu\t", mapcnt);
+
+	printf("%lx\t%s\n", offset, page_flag_name(flags));
+}
+
+static void show_summary(void)
+{
+	size_t i;
+
+	printf("             flags\tpage-count       MB"
+		"  symbolic-flags\t\t\tlong-symbolic-flags\n");
+
+	for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
+		if (nr_pages[i])
+			printf("0x%016llx\t%10lu %8lu  %s\t%s\n",
+				(unsigned long long)page_flags[i],
+				nr_pages[i],
+				pages2mb(nr_pages[i]),
+				page_flag_name(page_flags[i]),
+				page_flag_longname(page_flags[i]));
+	}
+
+	printf("             total\t%10lu %8lu\n",
+			total_pages, pages2mb(total_pages));
+}
+
+
+/*
+ * page flag filters
+ */
+
+static int bit_mask_ok(uint64_t flags)
+{
+	int i;
+
+	for (i = 0; i < nr_bit_filters; i++) {
+		if (opt_bits[i] == KPF_ALL_BITS) {
+			if ((flags & opt_mask[i]) == 0)
+				return 0;
+		} else {
+			if ((flags & opt_mask[i]) != opt_bits[i])
+				return 0;
+		}
+	}
+
+	return 1;
+}
+
+static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
+{
+	/* Anonymous pages overload PG_mappedtodisk */
+	if ((flags & BIT(ANON)) && (flags & BIT(MAPPEDTODISK)))
+		flags ^= BIT(MAPPEDTODISK) | BIT(ANON_EXCLUSIVE);
+
+	/* SLOB/SLUB overload several page flags */
+	if (flags & BIT(SLAB)) {
+		if (flags & BIT(PRIVATE))
+			flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
+		if (flags & BIT(ACTIVE))
+			flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
+		if (flags & BIT(ERROR))
+			flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
+	}
+
+	/* PG_reclaim is overloaded as PG_readahead in the read path */
+	if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
+		flags ^= BIT(RECLAIM) | BIT(READAHEAD);
+
+	if (pme & PM_SOFT_DIRTY)
+		flags |= BIT(SOFTDIRTY);
+	if (pme & PM_FILE)
+		flags |= BIT(FILE);
+	if (pme & PM_SWAP)
+		flags |= BIT(SWAP);
+	if (pme & PM_MMAP_EXCLUSIVE)
+		flags |= BIT(MMAP_EXCLUSIVE);
+
+	return flags;
+}
+
+static uint64_t well_known_flags(uint64_t flags)
+{
+	/* hide flags intended only for kernel hacker */
+	flags &= ~KPF_HACKERS_BITS;
+
+	/* hide non-hugeTLB compound pages */
+	if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
+		flags &= ~BITS_COMPOUND;
+
+	return flags;
+}
+
+static uint64_t kpageflags_flags(uint64_t flags, uint64_t pme)
+{
+	if (opt_raw)
+		flags = expand_overloaded_flags(flags, pme);
+	else
+		flags = well_known_flags(flags);
+
+	return flags;
+}
+
+/*
+ * page actions
+ */
+
+static void prepare_hwpoison_fd(void)
+{
+	char buf[MAX_PATH + 1];
+
+	hwpoison_debug_fs = debugfs__mount();
+	if (!hwpoison_debug_fs) {
+		perror("mount debugfs");
+		exit(EXIT_FAILURE);
+	}
+
+	if (opt_hwpoison && !hwpoison_inject_fd) {
+		snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
+			hwpoison_debug_fs);
+		hwpoison_inject_fd = checked_open(buf, O_WRONLY);
+	}
+
+	if (opt_unpoison && !hwpoison_forget_fd) {
+		snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
+			hwpoison_debug_fs);
+		hwpoison_forget_fd = checked_open(buf, O_WRONLY);
+	}
+}
+
+static int hwpoison_page(unsigned long offset)
+{
+	char buf[100];
+	int len;
+
+	len = sprintf(buf, "0x%lx\n", offset);
+	len = write(hwpoison_inject_fd, buf, len);
+	if (len < 0) {
+		perror("hwpoison inject");
+		return len;
+	}
+	return 0;
+}
+
+static int unpoison_page(unsigned long offset)
+{
+	char buf[100];
+	int len;
+
+	len = sprintf(buf, "0x%lx\n", offset);
+	len = write(hwpoison_forget_fd, buf, len);
+	if (len < 0) {
+		perror("hwpoison forget");
+		return len;
+	}
+	return 0;
+}
+
+static int mark_page_idle(unsigned long offset)
+{
+	static unsigned long off;
+	static uint64_t buf;
+	int len;
+
+	if ((offset / 64 == off / 64) || buf == 0) {
+		buf |= 1UL << (offset % 64);
+		off = offset;
+		return 0;
+	}
+
+	len = pwrite(page_idle_fd, &buf, 8, 8 * (off / 64));
+	if (len < 0) {
+		perror("mark page idle");
+		return len;
+	}
+
+	buf = 1UL << (offset % 64);
+	off = offset;
+
+	return 0;
+}
+
+/*
+ * page frame walker
+ */
+
+static size_t hash_slot(uint64_t flags)
+{
+	size_t k = HASH_KEY(flags);
+	size_t i;
+
+	/* Explicitly reserve slot 0 for flags 0: the following logic
+	 * cannot distinguish an unoccupied slot from slot (flags==0).
+	 */
+	if (flags == 0)
+		return 0;
+
+	/* search through the remaining (HASH_SIZE-1) slots */
+	for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
+		if (!k || k >= ARRAY_SIZE(page_flags))
+			k = 1;
+		if (page_flags[k] == 0) {
+			page_flags[k] = flags;
+			return k;
+		}
+		if (page_flags[k] == flags)
+			return k;
+	}
+
+	fatal("hash table full: bump up HASH_SHIFT?\n");
+	exit(EXIT_FAILURE);
+}
+
+static void add_page(unsigned long voffset, unsigned long offset,
+		     uint64_t flags, uint64_t cgroup, uint64_t mapcnt,
+		     uint64_t pme)
+{
+	flags = kpageflags_flags(flags, pme);
+
+	if (!bit_mask_ok(flags))
+		return;
+
+	if (opt_cgroup && cgroup != (uint64_t)opt_cgroup)
+		return;
+
+	if (opt_hwpoison)
+		hwpoison_page(offset);
+	if (opt_unpoison)
+		unpoison_page(offset);
+
+	if (opt_mark_idle)
+		mark_page_idle(offset);
+
+	if (opt_list == 1)
+		show_page_range(voffset, offset, 1, flags, cgroup, mapcnt);
+	else if (opt_list == 2)
+		show_page(voffset, offset, flags, cgroup, mapcnt);
+
+	nr_pages[hash_slot(flags)]++;
+	total_pages++;
+}
+
+#define KPAGEFLAGS_BATCH	(64 << 10)	/* 64k pages */
+static void walk_pfn(unsigned long voffset,
+		     unsigned long index,
+		     unsigned long count,
+		     uint64_t pme)
+{
+	uint64_t buf[KPAGEFLAGS_BATCH];
+	uint64_t cgi[KPAGEFLAGS_BATCH];
+	uint64_t cnt[KPAGEFLAGS_BATCH];
+	unsigned long batch;
+	unsigned long pages;
+	unsigned long i;
+
+	/*
+	 * kpagecgroup_read() reads only if kpagecgroup were opened, but
+	 * /proc/kpagecgroup might even not exist, so it's better to fill
+	 * them with zeros here.
+	 */
+	if (count == 1)
+		cgi[0] = 0;
+	else
+		memset(cgi, 0, sizeof cgi);
+
+	while (count) {
+		batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
+		pages = kpageflags_read(buf, index, batch);
+		if (pages == 0)
+			break;
+
+		if (kpagecgroup_read(cgi, index, pages) != pages)
+			fatal("kpagecgroup returned fewer pages than expected");
+
+		if (kpagecount_read(cnt, index, pages) != pages)
+			fatal("kpagecount returned fewer pages than expected");
+
+		for (i = 0; i < pages; i++)
+			add_page(voffset + i, index + i,
+				 buf[i], cgi[i], cnt[i], pme);
+
+		index += pages;
+		count -= pages;
+	}
+}
+
+static void walk_swap(unsigned long voffset, uint64_t pme)
+{
+	uint64_t flags = kpageflags_flags(0, pme);
+
+	if (!bit_mask_ok(flags))
+		return;
+
+	if (opt_cgroup)
+		return;
+
+	if (opt_list == 1)
+		show_page_range(voffset, pagemap_swap_offset(pme),
+				1, flags, 0, 0);
+	else if (opt_list == 2)
+		show_page(voffset, pagemap_swap_offset(pme), flags, 0, 0);
+
+	nr_pages[hash_slot(flags)]++;
+	total_pages++;
+}
+
+#define PAGEMAP_BATCH	(64 << 10)
+static void walk_vma(unsigned long index, unsigned long count)
+{
+	uint64_t buf[PAGEMAP_BATCH];
+	unsigned long batch;
+	unsigned long pages;
+	unsigned long pfn;
+	unsigned long i;
+
+	while (count) {
+		batch = min_t(unsigned long, count, PAGEMAP_BATCH);
+		pages = pagemap_read(buf, index, batch);
+		if (pages == 0)
+			break;
+
+		for (i = 0; i < pages; i++) {
+			pfn = pagemap_pfn(buf[i]);
+			if (pfn)
+				walk_pfn(index + i, pfn, 1, buf[i]);
+			if (buf[i] & PM_SWAP)
+				walk_swap(index + i, buf[i]);
+		}
+
+		index += pages;
+		count -= pages;
+	}
+}
+
+static void walk_task(unsigned long index, unsigned long count)
+{
+	const unsigned long end = index + count;
+	unsigned long start;
+	int i = 0;
+
+	while (index < end) {
+
+		while (pg_end[i] <= index)
+			if (++i >= nr_vmas)
+				return;
+		if (pg_start[i] >= end)
+			return;
+
+		start = max_t(unsigned long, pg_start[i], index);
+		index = min_t(unsigned long, pg_end[i], end);
+
+		assert(start < index);
+		walk_vma(start, index - start);
+	}
+}
+
+static void add_addr_range(unsigned long offset, unsigned long size)
+{
+	if (nr_addr_ranges >= MAX_ADDR_RANGES)
+		fatal("too many addr ranges\n");
+
+	opt_offset[nr_addr_ranges] = offset;
+	opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
+	nr_addr_ranges++;
+}
+
+static void walk_addr_ranges(void)
+{
+	int i;
+
+	kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
+
+	if (!nr_addr_ranges)
+		add_addr_range(0, ULONG_MAX);
+
+	for (i = 0; i < nr_addr_ranges; i++)
+		if (!opt_pid)
+			walk_pfn(opt_offset[i], opt_offset[i], opt_size[i], 0);
+		else
+			walk_task(opt_offset[i], opt_size[i]);
+
+	if (opt_mark_idle)
+		mark_page_idle(0);
+
+	close(kpageflags_fd);
+}
+
+
+/*
+ * user interface
+ */
+
+static const char *page_flag_type(uint64_t flag)
+{
+	if (flag & KPF_HACKERS_BITS)
+		return "(r)";
+	if (flag & KPF_OVERLOADED_BITS)
+		return "(o)";
+	return "   ";
+}
+
+static void usage(void)
+{
+	size_t i, j;
+
+	printf(
+"page-types [options]\n"
+"            -r|--raw                   Raw mode, for kernel developers\n"
+"            -d|--describe flags        Describe flags\n"
+"            -a|--addr    addr-spec     Walk a range of pages\n"
+"            -b|--bits    bits-spec     Walk pages with specified bits\n"
+"            -c|--cgroup  path|@inode   Walk pages within memory cgroup\n"
+"            -p|--pid     pid           Walk process address space\n"
+"            -f|--file    filename      Walk file address space\n"
+"            -i|--mark-idle             Mark pages idle\n"
+"            -l|--list                  Show page details in ranges\n"
+"            -L|--list-each             Show page details one by one\n"
+"            -C|--list-cgroup           Show cgroup inode for pages\n"
+"            -M|--list-mapcnt           Show page map count\n"
+"            -N|--no-summary            Don't show summary info\n"
+"            -X|--hwpoison              hwpoison pages\n"
+"            -x|--unpoison              unpoison pages\n"
+"            -F|--kpageflags filename   kpageflags file to parse\n"
+"            -h|--help                  Show this usage message\n"
+"flags:\n"
+"            0x10                       bitfield format, e.g.\n"
+"            anon                       bit-name, e.g.\n"
+"            0x10,anon                  comma-separated list, e.g.\n"
+"addr-spec:\n"
+"            N                          one page at offset N (unit: pages)\n"
+"            N+M                        pages range from N to N+M-1\n"
+"            N,M                        pages range from N to M-1\n"
+"            N,                         pages range from N to end\n"
+"            ,M                         pages range from 0 to M-1\n"
+"bits-spec:\n"
+"            bit1,bit2                  (flags & (bit1|bit2)) != 0\n"
+"            bit1,bit2=bit1             (flags & (bit1|bit2)) == bit1\n"
+"            bit1,~bit2                 (flags & (bit1|bit2)) == bit1\n"
+"            =bit1,bit2                 flags == (bit1|bit2)\n"
+"bit-names:\n"
+	);
+
+	for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
+		if (!page_flag_names[i])
+			continue;
+		printf("%16s%s", page_flag_names[i] + 2,
+				 page_flag_type(1ULL << i));
+		if (++j > 3) {
+			j = 0;
+			putchar('\n');
+		}
+	}
+	printf("\n                                   "
+		"(r) raw mode bits  (o) overloaded bits\n");
+}
+
+static unsigned long long parse_number(const char *str)
+{
+	unsigned long long n;
+
+	n = strtoll(str, NULL, 0);
+
+	if (n == 0 && str[0] != '0')
+		fatal("invalid name or number: %s\n", str);
+
+	return n;
+}
+
+static void parse_pid(const char *str)
+{
+	FILE *file;
+	char buf[5000];
+
+	opt_pid = parse_number(str);
+
+	sprintf(buf, "/proc/%d/pagemap", opt_pid);
+	pagemap_fd = checked_open(buf, O_RDONLY);
+
+	sprintf(buf, "/proc/%d/maps", opt_pid);
+	file = fopen(buf, "r");
+	if (!file) {
+		perror(buf);
+		exit(EXIT_FAILURE);
+	}
+
+	while (fgets(buf, sizeof(buf), file) != NULL) {
+		unsigned long vm_start;
+		unsigned long vm_end;
+		unsigned long long pgoff;
+		int major, minor;
+		char r, w, x, s;
+		unsigned long ino;
+		int n;
+
+		n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
+			   &vm_start,
+			   &vm_end,
+			   &r, &w, &x, &s,
+			   &pgoff,
+			   &major, &minor,
+			   &ino);
+		if (n < 10) {
+			fprintf(stderr, "unexpected line: %s\n", buf);
+			continue;
+		}
+		pg_start[nr_vmas] = vm_start / page_size;
+		pg_end[nr_vmas] = vm_end / page_size;
+		if (++nr_vmas >= MAX_VMAS) {
+			fprintf(stderr, "too many VMAs\n");
+			break;
+		}
+	}
+	fclose(file);
+}
+
+static void show_file(const char *name, const struct stat *st)
+{
+	unsigned long long size = st->st_size;
+	char atime[64], mtime[64];
+	long now = time(NULL);
+
+	printf("%s\tInode: %u\tSize: %llu (%llu pages)\n",
+			name, (unsigned)st->st_ino,
+			size, (size + page_size - 1) / page_size);
+
+	strftime(atime, sizeof(atime), "%c", localtime(&st->st_atime));
+	strftime(mtime, sizeof(mtime), "%c", localtime(&st->st_mtime));
+
+	printf("Modify: %s (%ld seconds ago)\nAccess: %s (%ld seconds ago)\n",
+			mtime, now - st->st_mtime,
+			atime, now - st->st_atime);
+}
+
+static sigjmp_buf sigbus_jmp;
+
+static void * volatile sigbus_addr;
+
+static void sigbus_handler(int sig, siginfo_t *info, void *ucontex)
+{
+	(void)sig;
+	(void)ucontex;
+	sigbus_addr = info ? info->si_addr : NULL;
+	siglongjmp(sigbus_jmp, 1);
+}
+
+static struct sigaction sigbus_action = {
+	.sa_sigaction = sigbus_handler,
+	.sa_flags = SA_SIGINFO,
+};
+
+static void walk_file_range(const char *name, int fd,
+			    unsigned long off, unsigned long end)
+{
+	uint8_t vec[PAGEMAP_BATCH];
+	uint64_t buf[PAGEMAP_BATCH], flags;
+	uint64_t cgroup = 0;
+	uint64_t mapcnt = 0;
+	unsigned long nr_pages, pfn, i;
+	ssize_t len;
+	void *ptr;
+	int first = 1;
+
+	for (; off < end; off += len) {
+		nr_pages = (end - off + page_size - 1) / page_size;
+		if (nr_pages > PAGEMAP_BATCH)
+			nr_pages = PAGEMAP_BATCH;
+		len = nr_pages * page_size;
+
+		ptr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, off);
+		if (ptr == MAP_FAILED)
+			fatal("mmap failed: %s", name);
+
+		/* determine cached pages */
+		if (mincore(ptr, len, vec))
+			fatal("mincore failed: %s", name);
+
+		/* turn off readahead */
+		if (madvise(ptr, len, MADV_RANDOM))
+			fatal("madvice failed: %s", name);
+
+		if (sigsetjmp(sigbus_jmp, 1)) {
+			end = off + sigbus_addr ? sigbus_addr - ptr : 0;
+			fprintf(stderr, "got sigbus at offset %lld: %s\n",
+					(long long)end, name);
+			goto got_sigbus;
+		}
+
+		/* populate ptes */
+		for (i = 0; i < nr_pages ; i++) {
+			if (vec[i] & 1)
+				(void)*(volatile int *)(ptr + i * page_size);
+		}
+got_sigbus:
+
+		/* turn off harvesting reference bits */
+		if (madvise(ptr, len, MADV_SEQUENTIAL))
+			fatal("madvice failed: %s", name);
+
+		if (pagemap_read(buf, (unsigned long)ptr / page_size,
+					nr_pages) != nr_pages)
+			fatal("cannot read pagemap");
+
+		munmap(ptr, len);
+
+		for (i = 0; i < nr_pages; i++) {
+			pfn = pagemap_pfn(buf[i]);
+			if (!pfn)
+				continue;
+			if (!kpageflags_read(&flags, pfn, 1))
+				continue;
+			if (!kpagecgroup_read(&cgroup, pfn, 1))
+				fatal("kpagecgroup_read failed");
+			if (!kpagecount_read(&mapcnt, pfn, 1))
+				fatal("kpagecount_read failed");
+			if (first && opt_list) {
+				first = 0;
+				flush_page_range();
+			}
+			add_page(off / page_size + i, pfn,
+				 flags, cgroup, mapcnt, buf[i]);
+		}
+	}
+}
+
+static void walk_file(const char *name, const struct stat *st)
+{
+	int i;
+	int fd;
+
+	fd = checked_open(name, O_RDONLY|O_NOATIME|O_NOFOLLOW);
+
+	if (!nr_addr_ranges)
+		add_addr_range(0, st->st_size / page_size);
+
+	for (i = 0; i < nr_addr_ranges; i++)
+		walk_file_range(name, fd, opt_offset[i] * page_size,
+				(opt_offset[i] + opt_size[i]) * page_size);
+
+	close(fd);
+}
+
+int walk_tree(const char *name, const struct stat *st, int type, struct FTW *f)
+{
+	(void)f;
+	switch (type) {
+	case FTW_F:
+		if (S_ISREG(st->st_mode))
+			walk_file(name, st);
+		break;
+	case FTW_DNR:
+		fprintf(stderr, "cannot read dir: %s\n", name);
+		break;
+	}
+	return 0;
+}
+
+struct stat st;
+
+static void walk_page_cache(void)
+{
+	kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
+	pagemap_fd = checked_open("/proc/self/pagemap", O_RDONLY);
+	sigaction(SIGBUS, &sigbus_action, NULL);
+
+	if (stat(opt_file, &st))
+		fatal("stat failed: %s\n", opt_file);
+
+	if (S_ISREG(st.st_mode)) {
+		walk_file(opt_file, &st);
+	} else if (S_ISDIR(st.st_mode)) {
+		/* do not follow symlinks and mountpoints */
+		if (nftw(opt_file, walk_tree, 64, FTW_MOUNT | FTW_PHYS) < 0)
+			fatal("nftw failed: %s\n", opt_file);
+	} else
+		fatal("unhandled file type: %s\n", opt_file);
+
+	close(kpageflags_fd);
+	close(pagemap_fd);
+	signal(SIGBUS, SIG_DFL);
+}
+
+static void parse_file(const char *name)
+{
+	opt_file = name;
+}
+
+static void parse_cgroup(const char *path)
+{
+	if (path[0] == '@') {
+		opt_cgroup = parse_number(path + 1);
+		return;
+	}
+
+	struct stat st;
+
+	if (stat(path, &st))
+		fatal("stat failed: %s: %m\n", path);
+
+	if (!S_ISDIR(st.st_mode))
+		fatal("cgroup supposed to be a directory: %s\n", path);
+
+	opt_cgroup = st.st_ino;
+}
+
+static void parse_addr_range(const char *optarg)
+{
+	unsigned long offset;
+	unsigned long size;
+	char *p;
+
+	p = strchr(optarg, ',');
+	if (!p)
+		p = strchr(optarg, '+');
+
+	if (p == optarg) {
+		offset = 0;
+		size   = parse_number(p + 1);
+	} else if (p) {
+		offset = parse_number(optarg);
+		if (p[1] == '\0')
+			size = ULONG_MAX;
+		else {
+			size = parse_number(p + 1);
+			if (*p == ',') {
+				if (size < offset)
+					fatal("invalid range: %lu,%lu\n",
+							offset, size);
+				size -= offset;
+			}
+		}
+	} else {
+		offset = parse_number(optarg);
+		size   = 1;
+	}
+
+	add_addr_range(offset, size);
+}
+
+static void add_bits_filter(uint64_t mask, uint64_t bits)
+{
+	if (nr_bit_filters >= MAX_BIT_FILTERS)
+		fatal("too much bit filters\n");
+
+	opt_mask[nr_bit_filters] = mask;
+	opt_bits[nr_bit_filters] = bits;
+	nr_bit_filters++;
+}
+
+static uint64_t parse_flag_name(const char *str, int len)
+{
+	size_t i;
+
+	if (!*str || !len)
+		return 0;
+
+	if (len <= 8 && !strncmp(str, "compound", len))
+		return BITS_COMPOUND;
+
+	for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
+		if (!page_flag_names[i])
+			continue;
+		if (!strncmp(str, page_flag_names[i] + 2, len))
+			return 1ULL << i;
+	}
+
+	return parse_number(str);
+}
+
+static uint64_t parse_flag_names(const char *str, int all)
+{
+	const char *p    = str;
+	uint64_t   flags = 0;
+
+	while (1) {
+		if (*p == ',' || *p == '=' || *p == '\0') {
+			if ((*str != '~') || (*str == '~' && all && *++str))
+				flags |= parse_flag_name(str, p - str);
+			if (*p != ',')
+				break;
+			str = p + 1;
+		}
+		p++;
+	}
+
+	return flags;
+}
+
+static void parse_bits_mask(const char *optarg)
+{
+	uint64_t mask;
+	uint64_t bits;
+	const char *p;
+
+	p = strchr(optarg, '=');
+	if (p == optarg) {
+		mask = KPF_ALL_BITS;
+		bits = parse_flag_names(p + 1, 0);
+	} else if (p) {
+		mask = parse_flag_names(optarg, 0);
+		bits = parse_flag_names(p + 1, 0);
+	} else if (strchr(optarg, '~')) {
+		mask = parse_flag_names(optarg, 1);
+		bits = parse_flag_names(optarg, 0);
+	} else {
+		mask = parse_flag_names(optarg, 0);
+		bits = KPF_ALL_BITS;
+	}
+
+	add_bits_filter(mask, bits);
+}
+
+static void parse_kpageflags(const char *name)
+{
+	opt_kpageflags = name;
+}
+
+static void describe_flags(const char *optarg)
+{
+	uint64_t flags = parse_flag_names(optarg, 0);
+
+	printf("0x%016llx\t%s\t%s\n",
+		(unsigned long long)flags,
+		page_flag_name(flags),
+		page_flag_longname(flags));
+}
+
+static const struct option opts[] = {
+	{ "raw"       , 0, NULL, 'r' },
+	{ "pid"       , 1, NULL, 'p' },
+	{ "file"      , 1, NULL, 'f' },
+	{ "addr"      , 1, NULL, 'a' },
+	{ "bits"      , 1, NULL, 'b' },
+	{ "cgroup"    , 1, NULL, 'c' },
+	{ "describe"  , 1, NULL, 'd' },
+	{ "mark-idle" , 0, NULL, 'i' },
+	{ "list"      , 0, NULL, 'l' },
+	{ "list-each" , 0, NULL, 'L' },
+	{ "list-cgroup", 0, NULL, 'C' },
+	{ "list-mapcnt", 0, NULL, 'M' },
+	{ "no-summary", 0, NULL, 'N' },
+	{ "hwpoison"  , 0, NULL, 'X' },
+	{ "unpoison"  , 0, NULL, 'x' },
+	{ "kpageflags", 0, NULL, 'F' },
+	{ "help"      , 0, NULL, 'h' },
+	{ NULL        , 0, NULL, 0 }
+};
+
+int main(int argc, char *argv[])
+{
+	int c;
+
+	page_size = getpagesize();
+
+	while ((c = getopt_long(argc, argv,
+				"rp:f:a:b:d:c:CilLMNXxF:h",
+				opts, NULL)) != -1) {
+		switch (c) {
+		case 'r':
+			opt_raw = 1;
+			break;
+		case 'p':
+			parse_pid(optarg);
+			break;
+		case 'f':
+			parse_file(optarg);
+			break;
+		case 'a':
+			parse_addr_range(optarg);
+			break;
+		case 'b':
+			parse_bits_mask(optarg);
+			break;
+		case 'c':
+			parse_cgroup(optarg);
+			break;
+		case 'C':
+			opt_list_cgroup = 1;
+			break;
+		case 'd':
+			describe_flags(optarg);
+			exit(0);
+		case 'i':
+			opt_mark_idle = 1;
+			break;
+		case 'l':
+			opt_list = 1;
+			break;
+		case 'L':
+			opt_list = 2;
+			break;
+		case 'M':
+			opt_list_mapcnt = 1;
+			break;
+		case 'N':
+			opt_no_summary = 1;
+			break;
+		case 'X':
+			opt_hwpoison = 1;
+			prepare_hwpoison_fd();
+			break;
+		case 'x':
+			opt_unpoison = 1;
+			prepare_hwpoison_fd();
+			break;
+		case 'F':
+			parse_kpageflags(optarg);
+			break;
+		case 'h':
+			usage();
+			exit(0);
+		default:
+			usage();
+			exit(1);
+		}
+	}
+
+	if (!opt_kpageflags)
+		opt_kpageflags = PROC_KPAGEFLAGS;
+
+	if (opt_cgroup || opt_list_cgroup)
+		kpagecgroup_fd = checked_open(PROC_KPAGECGROUP, O_RDONLY);
+
+	if (opt_list && opt_list_mapcnt)
+		kpagecount_fd = checked_open(PROC_KPAGECOUNT, O_RDONLY);
+
+	if (opt_mark_idle)
+		page_idle_fd = checked_open(SYS_KERNEL_MM_PAGE_IDLE, O_RDWR);
+
+	if (opt_list && opt_pid)
+		printf("voffset\t");
+	if (opt_list && opt_file)
+		printf("foffset\t");
+	if (opt_list && opt_list_cgroup)
+		printf("cgroup\t");
+	if (opt_list && opt_list_mapcnt)
+		printf("map-cnt\t");
+
+	if (opt_list == 1)
+		printf("offset\tlen\tflags\n");
+	if (opt_list == 2)
+		printf("offset\tflags\n");
+
+	if (opt_file)
+		walk_page_cache();
+	else
+		walk_addr_ranges();
+
+	if (opt_list == 1)
+		flush_page_range();
+
+	if (opt_no_summary)
+		return 0;
+
+	if (opt_list)
+		printf("\n\n");
+
+	if (opt_file) {
+		show_file(opt_file, &st);
+		printf("\n");
+	}
+
+	show_summary();
+
+	if (opt_list_mapcnt)
+		close(kpagecount_fd);
+
+	if (page_idle_fd >= 0)
+		close(page_idle_fd);
+
+	return 0;
+}