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, 671 insertions, 0 deletions

diff --git a/init/do_mounts.c b/init/do_mounts.c
new file mode 100644
index 000000000..811e94daf
--- /dev/null
+++ b/init/do_mounts.c
@@ -0,0 +1,671 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/ctype.h>
+#include <linux/fd.h>
+#include <linux/tty.h>
+#include <linux/suspend.h>
+#include <linux/root_dev.h>
+#include <linux/security.h>
+#include <linux/delay.h>
+#include <linux/mount.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/initrd.h>
+#include <linux/async.h>
+#include <linux/fs_struct.h>
+#include <linux/slab.h>
+#include <linux/ramfs.h>
+#include <linux/shmem_fs.h>
+
+#include <linux/nfs_fs.h>
+#include <linux/nfs_fs_sb.h>
+#include <linux/nfs_mount.h>
+#include <linux/raid/detect.h>
+#include <uapi/linux/mount.h>
+
+#include "do_mounts.h"
+
+int root_mountflags = MS_RDONLY | MS_SILENT;
+static char * __initdata root_device_name;
+static char __initdata saved_root_name[64];
+static int root_wait;
+
+dev_t ROOT_DEV;
+
+static int __init load_ramdisk(char *str)
+{
+	pr_warn("ignoring the deprecated load_ramdisk= option\n");
+	return 1;
+}
+__setup("load_ramdisk=", load_ramdisk);
+
+static int __init readonly(char *str)
+{
+	if (*str)
+		return 0;
+	root_mountflags |= MS_RDONLY;
+	return 1;
+}
+
+static int __init readwrite(char *str)
+{
+	if (*str)
+		return 0;
+	root_mountflags &= ~MS_RDONLY;
+	return 1;
+}
+
+__setup("ro", readonly);
+__setup("rw", readwrite);
+
+#ifdef CONFIG_BLOCK
+struct uuidcmp {
+	const char *uuid;
+	int len;
+};
+
+/**
+ * match_dev_by_uuid - callback for finding a partition using its uuid
+ * @dev:	device passed in by the caller
+ * @data:	opaque pointer to the desired struct uuidcmp to match
+ *
+ * Returns 1 if the device matches, and 0 otherwise.
+ */
+static int match_dev_by_uuid(struct device *dev, const void *data)
+{
+	struct block_device *bdev = dev_to_bdev(dev);
+	const struct uuidcmp *cmp = data;
+
+	if (!bdev->bd_meta_info ||
+	    strncasecmp(cmp->uuid, bdev->bd_meta_info->uuid, cmp->len))
+		return 0;
+	return 1;
+}
+
+/**
+ * devt_from_partuuid - looks up the dev_t of a partition by its UUID
+ * @uuid_str:	char array containing ascii UUID
+ *
+ * The function will return the first partition which contains a matching
+ * UUID value in its partition_meta_info struct.  This does not search
+ * by filesystem UUIDs.
+ *
+ * If @uuid_str is followed by a "/PARTNROFF=%d", then the number will be
+ * extracted and used as an offset from the partition identified by the UUID.
+ *
+ * Returns the matching dev_t on success or 0 on failure.
+ */
+static dev_t devt_from_partuuid(const char *uuid_str)
+{
+	struct uuidcmp cmp;
+	struct device *dev = NULL;
+	dev_t devt = 0;
+	int offset = 0;
+	char *slash;
+
+	cmp.uuid = uuid_str;
+
+	slash = strchr(uuid_str, '/');
+	/* Check for optional partition number offset attributes. */
+	if (slash) {
+		char c = 0;
+
+		/* Explicitly fail on poor PARTUUID syntax. */
+		if (sscanf(slash + 1, "PARTNROFF=%d%c", &offset, &c) != 1)
+			goto clear_root_wait;
+		cmp.len = slash - uuid_str;
+	} else {
+		cmp.len = strlen(uuid_str);
+	}
+
+	if (!cmp.len)
+		goto clear_root_wait;
+
+	dev = class_find_device(&block_class, NULL, &cmp, &match_dev_by_uuid);
+	if (!dev)
+		return 0;
+
+	if (offset) {
+		/*
+		 * Attempt to find the requested partition by adding an offset
+		 * to the partition number found by UUID.
+		 */
+		devt = part_devt(dev_to_disk(dev),
+				 dev_to_bdev(dev)->bd_partno + offset);
+	} else {
+		devt = dev->devt;
+	}
+
+	put_device(dev);
+	return devt;
+
+clear_root_wait:
+	pr_err("VFS: PARTUUID= is invalid.\n"
+	       "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");
+	if (root_wait)
+		pr_err("Disabling rootwait; root= is invalid.\n");
+	root_wait = 0;
+	return 0;
+}
+
+/**
+ * match_dev_by_label - callback for finding a partition using its label
+ * @dev:	device passed in by the caller
+ * @data:	opaque pointer to the label to match
+ *
+ * Returns 1 if the device matches, and 0 otherwise.
+ */
+static int match_dev_by_label(struct device *dev, const void *data)
+{
+	struct block_device *bdev = dev_to_bdev(dev);
+	const char *label = data;
+
+	if (!bdev->bd_meta_info || strcmp(label, bdev->bd_meta_info->volname))
+		return 0;
+	return 1;
+}
+
+static dev_t devt_from_partlabel(const char *label)
+{
+	struct device *dev;
+	dev_t devt = 0;
+
+	dev = class_find_device(&block_class, NULL, label, &match_dev_by_label);
+	if (dev) {
+		devt = dev->devt;
+		put_device(dev);
+	}
+
+	return devt;
+}
+
+static dev_t devt_from_devname(const char *name)
+{
+	dev_t devt = 0;
+	int part;
+	char s[32];
+	char *p;
+
+	if (strlen(name) > 31)
+		return 0;
+	strcpy(s, name);
+	for (p = s; *p; p++) {
+		if (*p == '/')
+			*p = '!';
+	}
+
+	devt = blk_lookup_devt(s, 0);
+	if (devt)
+		return devt;
+
+	/*
+	 * Try non-existent, but valid partition, which may only exist after
+	 * opening the device, like partitioned md devices.
+	 */
+	while (p > s && isdigit(p[-1]))
+		p--;
+	if (p == s || !*p || *p == '0')
+		return 0;
+
+	/* try disk name without <part number> */
+	part = simple_strtoul(p, NULL, 10);
+	*p = '\0';
+	devt = blk_lookup_devt(s, part);
+	if (devt)
+		return devt;
+
+	/* try disk name without p<part number> */
+	if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
+		return 0;
+	p[-1] = '\0';
+	return blk_lookup_devt(s, part);
+}
+#endif /* CONFIG_BLOCK */
+
+static dev_t devt_from_devnum(const char *name)
+{
+	unsigned maj, min, offset;
+	dev_t devt = 0;
+	char *p, dummy;
+
+	if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 ||
+	    sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3) {
+		devt = MKDEV(maj, min);
+		if (maj != MAJOR(devt) || min != MINOR(devt))
+			return 0;
+	} else {
+		devt = new_decode_dev(simple_strtoul(name, &p, 16));
+		if (*p)
+			return 0;
+	}
+
+	return devt;
+}
+
+/*
+ *	Convert a name into device number.  We accept the following variants:
+ *
+ *	1) <hex_major><hex_minor> device number in hexadecimal represents itself
+ *         no leading 0x, for example b302.
+ *	2) /dev/nfs represents Root_NFS (0xff)
+ *	3) /dev/<disk_name> represents the device number of disk
+ *	4) /dev/<disk_name><decimal> represents the device number
+ *         of partition - device number of disk plus the partition number
+ *	5) /dev/<disk_name>p<decimal> - same as the above, that form is
+ *	   used when disk name of partitioned disk ends on a digit.
+ *	6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
+ *	   unique id of a partition if the partition table provides it.
+ *	   The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
+ *	   partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
+ *	   filled hex representation of the 32-bit "NT disk signature", and PP
+ *	   is a zero-filled hex representation of the 1-based partition number.
+ *	7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to
+ *	   a partition with a known unique id.
+ *	8) <major>:<minor> major and minor number of the device separated by
+ *	   a colon.
+ *	9) PARTLABEL=<name> with name being the GPT partition label.
+ *	   MSDOS partitions do not support labels!
+ *	10) /dev/cifs represents Root_CIFS (0xfe)
+ *
+ *	If name doesn't have fall into the categories above, we return (0,0).
+ *	block_class is used to check if something is a disk name. If the disk
+ *	name contains slashes, the device name has them replaced with
+ *	bangs.
+ */
+dev_t name_to_dev_t(const char *name)
+{
+	if (strcmp(name, "/dev/nfs") == 0)
+		return Root_NFS;
+	if (strcmp(name, "/dev/cifs") == 0)
+		return Root_CIFS;
+	if (strcmp(name, "/dev/ram") == 0)
+		return Root_RAM0;
+#ifdef CONFIG_BLOCK
+	if (strncmp(name, "PARTUUID=", 9) == 0)
+		return devt_from_partuuid(name + 9);
+	if (strncmp(name, "PARTLABEL=", 10) == 0)
+		return devt_from_partlabel(name + 10);
+	if (strncmp(name, "/dev/", 5) == 0)
+		return devt_from_devname(name + 5);
+#endif
+	return devt_from_devnum(name);
+}
+EXPORT_SYMBOL_GPL(name_to_dev_t);
+
+static int __init root_dev_setup(char *line)
+{
+	strscpy(saved_root_name, line, sizeof(saved_root_name));
+	return 1;
+}
+
+__setup("root=", root_dev_setup);
+
+static int __init rootwait_setup(char *str)
+{
+	if (*str)
+		return 0;
+	root_wait = 1;
+	return 1;
+}
+
+__setup("rootwait", rootwait_setup);
+
+static char * __initdata root_mount_data;
+static int __init root_data_setup(char *str)
+{
+	root_mount_data = str;
+	return 1;
+}
+
+static char * __initdata root_fs_names;
+static int __init fs_names_setup(char *str)
+{
+	root_fs_names = str;
+	return 1;
+}
+
+static unsigned int __initdata root_delay;
+static int __init root_delay_setup(char *str)
+{
+	root_delay = simple_strtoul(str, NULL, 0);
+	return 1;
+}
+
+__setup("rootflags=", root_data_setup);
+__setup("rootfstype=", fs_names_setup);
+__setup("rootdelay=", root_delay_setup);
+
+/* This can return zero length strings. Caller should check */
+static int __init split_fs_names(char *page, size_t size, char *names)
+{
+	int count = 1;
+	char *p = page;
+
+	strscpy(p, root_fs_names, size);
+	while (*p++) {
+		if (p[-1] == ',') {
+			p[-1] = '\0';
+			count++;
+		}
+	}
+
+	return count;
+}
+
+static int __init do_mount_root(const char *name, const char *fs,
+				 const int flags, const void *data)
+{
+	struct super_block *s;
+	struct page *p = NULL;
+	char *data_page = NULL;
+	int ret;
+
+	if (data) {
+		/* init_mount() requires a full page as fifth argument */
+		p = alloc_page(GFP_KERNEL);
+		if (!p)
+			return -ENOMEM;
+		data_page = page_address(p);
+		/* zero-pad. init_mount() will make sure it's terminated */
+		strncpy(data_page, data, PAGE_SIZE);
+	}
+
+	ret = init_mount(name, "/root", fs, flags, data_page);
+	if (ret)
+		goto out;
+
+	init_chdir("/root");
+	s = current->fs->pwd.dentry->d_sb;
+	ROOT_DEV = s->s_dev;
+	printk(KERN_INFO
+	       "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
+	       s->s_type->name,
+	       sb_rdonly(s) ? " readonly" : "",
+	       MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
+
+out:
+	if (p)
+		put_page(p);
+	return ret;
+}
+
+void __init mount_block_root(char *name, int flags)
+{
+	struct page *page = alloc_page(GFP_KERNEL);
+	char *fs_names = page_address(page);
+	char *p;
+	char b[BDEVNAME_SIZE];
+	int num_fs, i;
+
+	scnprintf(b, BDEVNAME_SIZE, "unknown-block(%u,%u)",
+		  MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
+	if (root_fs_names)
+		num_fs = split_fs_names(fs_names, PAGE_SIZE, root_fs_names);
+	else
+		num_fs = list_bdev_fs_names(fs_names, PAGE_SIZE);
+retry:
+	for (i = 0, p = fs_names; i < num_fs; i++, p += strlen(p)+1) {
+		int err;
+
+		if (!*p)
+			continue;
+		err = do_mount_root(name, p, flags, root_mount_data);
+		switch (err) {
+			case 0:
+				goto out;
+			case -EACCES:
+			case -EINVAL:
+				continue;
+		}
+	        /*
+		 * Allow the user to distinguish between failed sys_open
+		 * and bad superblock on root device.
+		 * and give them a list of the available devices
+		 */
+		printk("VFS: Cannot open root device \"%s\" or %s: error %d\n",
+				root_device_name, b, err);
+		printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
+
+		printk_all_partitions();
+		panic("VFS: Unable to mount root fs on %s", b);
+	}
+	if (!(flags & SB_RDONLY)) {
+		flags |= SB_RDONLY;
+		goto retry;
+	}
+
+	printk("List of all partitions:\n");
+	printk_all_partitions();
+	printk("No filesystem could mount root, tried: ");
+	for (i = 0, p = fs_names; i < num_fs; i++, p += strlen(p)+1)
+		printk(" %s", p);
+	printk("\n");
+	panic("VFS: Unable to mount root fs on %s", b);
+out:
+	put_page(page);
+}
+ 
+#ifdef CONFIG_ROOT_NFS
+
+#define NFSROOT_TIMEOUT_MIN	5
+#define NFSROOT_TIMEOUT_MAX	30
+#define NFSROOT_RETRY_MAX	5
+
+static int __init mount_nfs_root(void)
+{
+	char *root_dev, *root_data;
+	unsigned int timeout;
+	int try, err;
+
+	err = nfs_root_data(&root_dev, &root_data);
+	if (err != 0)
+		return 0;
+
+	/*
+	 * The server or network may not be ready, so try several
+	 * times.  Stop after a few tries in case the client wants
+	 * to fall back to other boot methods.
+	 */
+	timeout = NFSROOT_TIMEOUT_MIN;
+	for (try = 1; ; try++) {
+		err = do_mount_root(root_dev, "nfs",
+					root_mountflags, root_data);
+		if (err == 0)
+			return 1;
+		if (try > NFSROOT_RETRY_MAX)
+			break;
+
+		/* Wait, in case the server refused us immediately */
+		ssleep(timeout);
+		timeout <<= 1;
+		if (timeout > NFSROOT_TIMEOUT_MAX)
+			timeout = NFSROOT_TIMEOUT_MAX;
+	}
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_CIFS_ROOT
+
+extern int cifs_root_data(char **dev, char **opts);
+
+#define CIFSROOT_TIMEOUT_MIN	5
+#define CIFSROOT_TIMEOUT_MAX	30
+#define CIFSROOT_RETRY_MAX	5
+
+static int __init mount_cifs_root(void)
+{
+	char *root_dev, *root_data;
+	unsigned int timeout;
+	int try, err;
+
+	err = cifs_root_data(&root_dev, &root_data);
+	if (err != 0)
+		return 0;
+
+	timeout = CIFSROOT_TIMEOUT_MIN;
+	for (try = 1; ; try++) {
+		err = do_mount_root(root_dev, "cifs", root_mountflags,
+				    root_data);
+		if (err == 0)
+			return 1;
+		if (try > CIFSROOT_RETRY_MAX)
+			break;
+
+		ssleep(timeout);
+		timeout <<= 1;
+		if (timeout > CIFSROOT_TIMEOUT_MAX)
+			timeout = CIFSROOT_TIMEOUT_MAX;
+	}
+	return 0;
+}
+#endif
+
+static bool __init fs_is_nodev(char *fstype)
+{
+	struct file_system_type *fs = get_fs_type(fstype);
+	bool ret = false;
+
+	if (fs) {
+		ret = !(fs->fs_flags & FS_REQUIRES_DEV);
+		put_filesystem(fs);
+	}
+
+	return ret;
+}
+
+static int __init mount_nodev_root(void)
+{
+	char *fs_names, *fstype;
+	int err = -EINVAL;
+	int num_fs, i;
+
+	fs_names = (void *)__get_free_page(GFP_KERNEL);
+	if (!fs_names)
+		return -EINVAL;
+	num_fs = split_fs_names(fs_names, PAGE_SIZE, root_fs_names);
+
+	for (i = 0, fstype = fs_names; i < num_fs;
+	     i++, fstype += strlen(fstype) + 1) {
+		if (!*fstype)
+			continue;
+		if (!fs_is_nodev(fstype))
+			continue;
+		err = do_mount_root(root_device_name, fstype, root_mountflags,
+				    root_mount_data);
+		if (!err)
+			break;
+	}
+
+	free_page((unsigned long)fs_names);
+	return err;
+}
+
+void __init mount_root(void)
+{
+#ifdef CONFIG_ROOT_NFS
+	if (ROOT_DEV == Root_NFS) {
+		if (!mount_nfs_root())
+			printk(KERN_ERR "VFS: Unable to mount root fs via NFS.\n");
+		return;
+	}
+#endif
+#ifdef CONFIG_CIFS_ROOT
+	if (ROOT_DEV == Root_CIFS) {
+		if (!mount_cifs_root())
+			printk(KERN_ERR "VFS: Unable to mount root fs via SMB.\n");
+		return;
+	}
+#endif
+	if (ROOT_DEV == 0 && root_device_name && root_fs_names) {
+		if (mount_nodev_root() == 0)
+			return;
+	}
+#ifdef CONFIG_BLOCK
+	{
+		int err = create_dev("/dev/root", ROOT_DEV);
+
+		if (err < 0)
+			pr_emerg("Failed to create /dev/root: %d\n", err);
+		mount_block_root("/dev/root", root_mountflags);
+	}
+#endif
+}
+
+/*
+ * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
+ */
+void __init prepare_namespace(void)
+{
+	if (root_delay) {
+		printk(KERN_INFO "Waiting %d sec before mounting root device...\n",
+		       root_delay);
+		ssleep(root_delay);
+	}
+
+	/*
+	 * wait for the known devices to complete their probing
+	 *
+	 * Note: this is a potential source of long boot delays.
+	 * For example, it is not atypical to wait 5 seconds here
+	 * for the touchpad of a laptop to initialize.
+	 */
+	wait_for_device_probe();
+
+	md_run_setup();
+
+	if (saved_root_name[0]) {
+		root_device_name = saved_root_name;
+		if (!strncmp(root_device_name, "mtd", 3) ||
+		    !strncmp(root_device_name, "ubi", 3)) {
+			mount_block_root(root_device_name, root_mountflags);
+			goto out;
+		}
+		ROOT_DEV = name_to_dev_t(root_device_name);
+		if (strncmp(root_device_name, "/dev/", 5) == 0)
+			root_device_name += 5;
+	}
+
+	if (initrd_load())
+		goto out;
+
+	/* wait for any asynchronous scanning to complete */
+	if ((ROOT_DEV == 0) && root_wait) {
+		printk(KERN_INFO "Waiting for root device %s...\n",
+			saved_root_name);
+		while (driver_probe_done() != 0 ||
+			(ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
+			msleep(5);
+		async_synchronize_full();
+	}
+
+	mount_root();
+out:
+	devtmpfs_mount();
+	init_mount(".", "/", NULL, MS_MOVE, NULL);
+	init_chroot(".");
+}
+
+static bool is_tmpfs;
+static int rootfs_init_fs_context(struct fs_context *fc)
+{
+	if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs)
+		return shmem_init_fs_context(fc);
+
+	return ramfs_init_fs_context(fc);
+}
+
+struct file_system_type rootfs_fs_type = {
+	.name		= "rootfs",
+	.init_fs_context = rootfs_init_fs_context,
+	.kill_sb	= kill_litter_super,
+};
+
+void __init init_rootfs(void)
+{
+	if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] &&
+		(!root_fs_names || strstr(root_fs_names, "tmpfs")))
+		is_tmpfs = true;
+}