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, 788 insertions, 0 deletions

diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
new file mode 100644
index 000000000..b536befd8
--- /dev/null
+++ b/drivers/md/raid0.c
@@ -0,0 +1,788 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+   raid0.c : Multiple Devices driver for Linux
+	     Copyright (C) 1994-96 Marc ZYNGIER
+	     <zyngier@ufr-info-p7.ibp.fr> or
+	     <maz@gloups.fdn.fr>
+	     Copyright (C) 1999, 2000 Ingo Molnar, Red Hat
+
+   RAID-0 management functions.
+
+*/
+
+#include <linux/blkdev.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <trace/events/block.h>
+#include "md.h"
+#include "raid0.h"
+#include "raid5.h"
+
+static int default_layout = 0;
+module_param(default_layout, int, 0644);
+
+#define UNSUPPORTED_MDDEV_FLAGS		\
+	((1L << MD_HAS_JOURNAL) |	\
+	 (1L << MD_JOURNAL_CLEAN) |	\
+	 (1L << MD_FAILFAST_SUPPORTED) |\
+	 (1L << MD_HAS_PPL) |		\
+	 (1L << MD_HAS_MULTIPLE_PPLS))
+
+/*
+ * inform the user of the raid configuration
+*/
+static void dump_zones(struct mddev *mddev)
+{
+	int j, k;
+	sector_t zone_size = 0;
+	sector_t zone_start = 0;
+	struct r0conf *conf = mddev->private;
+	int raid_disks = conf->strip_zone[0].nb_dev;
+	pr_debug("md: RAID0 configuration for %s - %d zone%s\n",
+		 mdname(mddev),
+		 conf->nr_strip_zones, conf->nr_strip_zones==1?"":"s");
+	for (j = 0; j < conf->nr_strip_zones; j++) {
+		char line[200];
+		int len = 0;
+
+		for (k = 0; k < conf->strip_zone[j].nb_dev; k++)
+			len += scnprintf(line+len, 200-len, "%s%pg", k?"/":"",
+				conf->devlist[j * raid_disks + k]->bdev);
+		pr_debug("md: zone%d=[%s]\n", j, line);
+
+		zone_size  = conf->strip_zone[j].zone_end - zone_start;
+		pr_debug("      zone-offset=%10lluKB, device-offset=%10lluKB, size=%10lluKB\n",
+			(unsigned long long)zone_start>>1,
+			(unsigned long long)conf->strip_zone[j].dev_start>>1,
+			(unsigned long long)zone_size>>1);
+		zone_start = conf->strip_zone[j].zone_end;
+	}
+}
+
+static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
+{
+	int i, c, err;
+	sector_t curr_zone_end, sectors;
+	struct md_rdev *smallest, *rdev1, *rdev2, *rdev, **dev;
+	struct strip_zone *zone;
+	int cnt;
+	struct r0conf *conf = kzalloc(sizeof(*conf), GFP_KERNEL);
+	unsigned blksize = 512;
+
+	*private_conf = ERR_PTR(-ENOMEM);
+	if (!conf)
+		return -ENOMEM;
+	rdev_for_each(rdev1, mddev) {
+		pr_debug("md/raid0:%s: looking at %pg\n",
+			 mdname(mddev),
+			 rdev1->bdev);
+		c = 0;
+
+		/* round size to chunk_size */
+		sectors = rdev1->sectors;
+		sector_div(sectors, mddev->chunk_sectors);
+		rdev1->sectors = sectors * mddev->chunk_sectors;
+
+		blksize = max(blksize, queue_logical_block_size(
+				      rdev1->bdev->bd_disk->queue));
+
+		rdev_for_each(rdev2, mddev) {
+			pr_debug("md/raid0:%s:   comparing %pg(%llu)"
+				 " with %pg(%llu)\n",
+				 mdname(mddev),
+				 rdev1->bdev,
+				 (unsigned long long)rdev1->sectors,
+				 rdev2->bdev,
+				 (unsigned long long)rdev2->sectors);
+			if (rdev2 == rdev1) {
+				pr_debug("md/raid0:%s:   END\n",
+					 mdname(mddev));
+				break;
+			}
+			if (rdev2->sectors == rdev1->sectors) {
+				/*
+				 * Not unique, don't count it as a new
+				 * group
+				 */
+				pr_debug("md/raid0:%s:   EQUAL\n",
+					 mdname(mddev));
+				c = 1;
+				break;
+			}
+			pr_debug("md/raid0:%s:   NOT EQUAL\n",
+				 mdname(mddev));
+		}
+		if (!c) {
+			pr_debug("md/raid0:%s:   ==> UNIQUE\n",
+				 mdname(mddev));
+			conf->nr_strip_zones++;
+			pr_debug("md/raid0:%s: %d zones\n",
+				 mdname(mddev), conf->nr_strip_zones);
+		}
+	}
+	pr_debug("md/raid0:%s: FINAL %d zones\n",
+		 mdname(mddev), conf->nr_strip_zones);
+
+	/*
+	 * now since we have the hard sector sizes, we can make sure
+	 * chunk size is a multiple of that sector size
+	 */
+	if ((mddev->chunk_sectors << 9) % blksize) {
+		pr_warn("md/raid0:%s: chunk_size of %d not multiple of block size %d\n",
+			mdname(mddev),
+			mddev->chunk_sectors << 9, blksize);
+		err = -EINVAL;
+		goto abort;
+	}
+
+	err = -ENOMEM;
+	conf->strip_zone = kcalloc(conf->nr_strip_zones,
+				   sizeof(struct strip_zone),
+				   GFP_KERNEL);
+	if (!conf->strip_zone)
+		goto abort;
+	conf->devlist = kzalloc(array3_size(sizeof(struct md_rdev *),
+					    conf->nr_strip_zones,
+					    mddev->raid_disks),
+				GFP_KERNEL);
+	if (!conf->devlist)
+		goto abort;
+
+	/* The first zone must contain all devices, so here we check that
+	 * there is a proper alignment of slots to devices and find them all
+	 */
+	zone = &conf->strip_zone[0];
+	cnt = 0;
+	smallest = NULL;
+	dev = conf->devlist;
+	err = -EINVAL;
+	rdev_for_each(rdev1, mddev) {
+		int j = rdev1->raid_disk;
+
+		if (mddev->level == 10) {
+			/* taking over a raid10-n2 array */
+			j /= 2;
+			rdev1->new_raid_disk = j;
+		}
+
+		if (mddev->level == 1) {
+			/* taiking over a raid1 array-
+			 * we have only one active disk
+			 */
+			j = 0;
+			rdev1->new_raid_disk = j;
+		}
+
+		if (j < 0) {
+			pr_warn("md/raid0:%s: remove inactive devices before converting to RAID0\n",
+				mdname(mddev));
+			goto abort;
+		}
+		if (j >= mddev->raid_disks) {
+			pr_warn("md/raid0:%s: bad disk number %d - aborting!\n",
+				mdname(mddev), j);
+			goto abort;
+		}
+		if (dev[j]) {
+			pr_warn("md/raid0:%s: multiple devices for %d - aborting!\n",
+				mdname(mddev), j);
+			goto abort;
+		}
+		dev[j] = rdev1;
+
+		if (!smallest || (rdev1->sectors < smallest->sectors))
+			smallest = rdev1;
+		cnt++;
+	}
+	if (cnt != mddev->raid_disks) {
+		pr_warn("md/raid0:%s: too few disks (%d of %d) - aborting!\n",
+			mdname(mddev), cnt, mddev->raid_disks);
+		goto abort;
+	}
+	zone->nb_dev = cnt;
+	zone->zone_end = smallest->sectors * cnt;
+
+	curr_zone_end = zone->zone_end;
+
+	/* now do the other zones */
+	for (i = 1; i < conf->nr_strip_zones; i++)
+	{
+		int j;
+
+		zone = conf->strip_zone + i;
+		dev = conf->devlist + i * mddev->raid_disks;
+
+		pr_debug("md/raid0:%s: zone %d\n", mdname(mddev), i);
+		zone->dev_start = smallest->sectors;
+		smallest = NULL;
+		c = 0;
+
+		for (j=0; j<cnt; j++) {
+			rdev = conf->devlist[j];
+			if (rdev->sectors <= zone->dev_start) {
+				pr_debug("md/raid0:%s: checking %pg ... nope\n",
+					 mdname(mddev),
+					 rdev->bdev);
+				continue;
+			}
+			pr_debug("md/raid0:%s: checking %pg ..."
+				 " contained as device %d\n",
+				 mdname(mddev),
+				 rdev->bdev, c);
+			dev[c] = rdev;
+			c++;
+			if (!smallest || rdev->sectors < smallest->sectors) {
+				smallest = rdev;
+				pr_debug("md/raid0:%s:  (%llu) is smallest!.\n",
+					 mdname(mddev),
+					 (unsigned long long)rdev->sectors);
+			}
+		}
+
+		zone->nb_dev = c;
+		sectors = (smallest->sectors - zone->dev_start) * c;
+		pr_debug("md/raid0:%s: zone->nb_dev: %d, sectors: %llu\n",
+			 mdname(mddev),
+			 zone->nb_dev, (unsigned long long)sectors);
+
+		curr_zone_end += sectors;
+		zone->zone_end = curr_zone_end;
+
+		pr_debug("md/raid0:%s: current zone start: %llu\n",
+			 mdname(mddev),
+			 (unsigned long long)smallest->sectors);
+	}
+
+	if (conf->nr_strip_zones == 1 || conf->strip_zone[1].nb_dev == 1) {
+		conf->layout = RAID0_ORIG_LAYOUT;
+	} else if (mddev->layout == RAID0_ORIG_LAYOUT ||
+		   mddev->layout == RAID0_ALT_MULTIZONE_LAYOUT) {
+		conf->layout = mddev->layout;
+	} else if (default_layout == RAID0_ORIG_LAYOUT ||
+		   default_layout == RAID0_ALT_MULTIZONE_LAYOUT) {
+		conf->layout = default_layout;
+	} else {
+		pr_err("md/raid0:%s: cannot assemble multi-zone RAID0 with default_layout setting\n",
+		       mdname(mddev));
+		pr_err("md/raid0: please set raid0.default_layout to 1 or 2\n");
+		err = -EOPNOTSUPP;
+		goto abort;
+	}
+
+	pr_debug("md/raid0:%s: done.\n", mdname(mddev));
+	*private_conf = conf;
+
+	return 0;
+abort:
+	kfree(conf->strip_zone);
+	kfree(conf->devlist);
+	kfree(conf);
+	*private_conf = ERR_PTR(err);
+	return err;
+}
+
+/* Find the zone which holds a particular offset
+ * Update *sectorp to be an offset in that zone
+ */
+static struct strip_zone *find_zone(struct r0conf *conf,
+				    sector_t *sectorp)
+{
+	int i;
+	struct strip_zone *z = conf->strip_zone;
+	sector_t sector = *sectorp;
+
+	for (i = 0; i < conf->nr_strip_zones; i++)
+		if (sector < z[i].zone_end) {
+			if (i)
+				*sectorp = sector - z[i-1].zone_end;
+			return z + i;
+		}
+	BUG();
+}
+
+/*
+ * remaps the bio to the target device. we separate two flows.
+ * power 2 flow and a general flow for the sake of performance
+*/
+static struct md_rdev *map_sector(struct mddev *mddev, struct strip_zone *zone,
+				sector_t sector, sector_t *sector_offset)
+{
+	unsigned int sect_in_chunk;
+	sector_t chunk;
+	struct r0conf *conf = mddev->private;
+	int raid_disks = conf->strip_zone[0].nb_dev;
+	unsigned int chunk_sects = mddev->chunk_sectors;
+
+	if (is_power_of_2(chunk_sects)) {
+		int chunksect_bits = ffz(~chunk_sects);
+		/* find the sector offset inside the chunk */
+		sect_in_chunk  = sector & (chunk_sects - 1);
+		sector >>= chunksect_bits;
+		/* chunk in zone */
+		chunk = *sector_offset;
+		/* quotient is the chunk in real device*/
+		sector_div(chunk, zone->nb_dev << chunksect_bits);
+	} else{
+		sect_in_chunk = sector_div(sector, chunk_sects);
+		chunk = *sector_offset;
+		sector_div(chunk, chunk_sects * zone->nb_dev);
+	}
+	/*
+	*  position the bio over the real device
+	*  real sector = chunk in device + starting of zone
+	*	+ the position in the chunk
+	*/
+	*sector_offset = (chunk * chunk_sects) + sect_in_chunk;
+	return conf->devlist[(zone - conf->strip_zone)*raid_disks
+			     + sector_div(sector, zone->nb_dev)];
+}
+
+static sector_t raid0_size(struct mddev *mddev, sector_t sectors, int raid_disks)
+{
+	sector_t array_sectors = 0;
+	struct md_rdev *rdev;
+
+	WARN_ONCE(sectors || raid_disks,
+		  "%s does not support generic reshape\n", __func__);
+
+	rdev_for_each(rdev, mddev)
+		array_sectors += (rdev->sectors &
+				  ~(sector_t)(mddev->chunk_sectors-1));
+
+	return array_sectors;
+}
+
+static void free_conf(struct mddev *mddev, struct r0conf *conf)
+{
+	kfree(conf->strip_zone);
+	kfree(conf->devlist);
+	kfree(conf);
+}
+
+static void raid0_free(struct mddev *mddev, void *priv)
+{
+	struct r0conf *conf = priv;
+
+	free_conf(mddev, conf);
+	acct_bioset_exit(mddev);
+}
+
+static int raid0_run(struct mddev *mddev)
+{
+	struct r0conf *conf;
+	int ret;
+
+	if (mddev->chunk_sectors == 0) {
+		pr_warn("md/raid0:%s: chunk size must be set.\n", mdname(mddev));
+		return -EINVAL;
+	}
+	if (md_check_no_bitmap(mddev))
+		return -EINVAL;
+
+	if (acct_bioset_init(mddev)) {
+		pr_err("md/raid0:%s: alloc acct bioset failed.\n", mdname(mddev));
+		return -ENOMEM;
+	}
+
+	/* if private is not null, we are here after takeover */
+	if (mddev->private == NULL) {
+		ret = create_strip_zones(mddev, &conf);
+		if (ret < 0)
+			goto exit_acct_set;
+		mddev->private = conf;
+	}
+	conf = mddev->private;
+	if (mddev->queue) {
+		struct md_rdev *rdev;
+
+		blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors);
+		blk_queue_max_write_zeroes_sectors(mddev->queue, mddev->chunk_sectors);
+
+		blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9);
+		blk_queue_io_opt(mddev->queue,
+				 (mddev->chunk_sectors << 9) * mddev->raid_disks);
+
+		rdev_for_each(rdev, mddev) {
+			disk_stack_limits(mddev->gendisk, rdev->bdev,
+					  rdev->data_offset << 9);
+		}
+	}
+
+	/* calculate array device size */
+	md_set_array_sectors(mddev, raid0_size(mddev, 0, 0));
+
+	pr_debug("md/raid0:%s: md_size is %llu sectors.\n",
+		 mdname(mddev),
+		 (unsigned long long)mddev->array_sectors);
+
+	dump_zones(mddev);
+
+	ret = md_integrity_register(mddev);
+	if (ret)
+		goto free;
+
+	return ret;
+
+free:
+	free_conf(mddev, conf);
+exit_acct_set:
+	acct_bioset_exit(mddev);
+	return ret;
+}
+
+static void raid0_handle_discard(struct mddev *mddev, struct bio *bio)
+{
+	struct r0conf *conf = mddev->private;
+	struct strip_zone *zone;
+	sector_t start = bio->bi_iter.bi_sector;
+	sector_t end;
+	unsigned int stripe_size;
+	sector_t first_stripe_index, last_stripe_index;
+	sector_t start_disk_offset;
+	unsigned int start_disk_index;
+	sector_t end_disk_offset;
+	unsigned int end_disk_index;
+	unsigned int disk;
+
+	zone = find_zone(conf, &start);
+
+	if (bio_end_sector(bio) > zone->zone_end) {
+		struct bio *split = bio_split(bio,
+			zone->zone_end - bio->bi_iter.bi_sector, GFP_NOIO,
+			&mddev->bio_set);
+		bio_chain(split, bio);
+		submit_bio_noacct(bio);
+		bio = split;
+		end = zone->zone_end;
+	} else
+		end = bio_end_sector(bio);
+
+	if (zone != conf->strip_zone)
+		end = end - zone[-1].zone_end;
+
+	/* Now start and end is the offset in zone */
+	stripe_size = zone->nb_dev * mddev->chunk_sectors;
+
+	first_stripe_index = start;
+	sector_div(first_stripe_index, stripe_size);
+	last_stripe_index = end;
+	sector_div(last_stripe_index, stripe_size);
+
+	start_disk_index = (int)(start - first_stripe_index * stripe_size) /
+		mddev->chunk_sectors;
+	start_disk_offset = ((int)(start - first_stripe_index * stripe_size) %
+		mddev->chunk_sectors) +
+		first_stripe_index * mddev->chunk_sectors;
+	end_disk_index = (int)(end - last_stripe_index * stripe_size) /
+		mddev->chunk_sectors;
+	end_disk_offset = ((int)(end - last_stripe_index * stripe_size) %
+		mddev->chunk_sectors) +
+		last_stripe_index * mddev->chunk_sectors;
+
+	for (disk = 0; disk < zone->nb_dev; disk++) {
+		sector_t dev_start, dev_end;
+		struct md_rdev *rdev;
+
+		if (disk < start_disk_index)
+			dev_start = (first_stripe_index + 1) *
+				mddev->chunk_sectors;
+		else if (disk > start_disk_index)
+			dev_start = first_stripe_index * mddev->chunk_sectors;
+		else
+			dev_start = start_disk_offset;
+
+		if (disk < end_disk_index)
+			dev_end = (last_stripe_index + 1) * mddev->chunk_sectors;
+		else if (disk > end_disk_index)
+			dev_end = last_stripe_index * mddev->chunk_sectors;
+		else
+			dev_end = end_disk_offset;
+
+		if (dev_end <= dev_start)
+			continue;
+
+		rdev = conf->devlist[(zone - conf->strip_zone) *
+			conf->strip_zone[0].nb_dev + disk];
+		md_submit_discard_bio(mddev, rdev, bio,
+			dev_start + zone->dev_start + rdev->data_offset,
+			dev_end - dev_start);
+	}
+	bio_endio(bio);
+}
+
+static bool raid0_make_request(struct mddev *mddev, struct bio *bio)
+{
+	struct r0conf *conf = mddev->private;
+	struct strip_zone *zone;
+	struct md_rdev *tmp_dev;
+	sector_t bio_sector;
+	sector_t sector;
+	sector_t orig_sector;
+	unsigned chunk_sects;
+	unsigned sectors;
+
+	if (unlikely(bio->bi_opf & REQ_PREFLUSH)
+	    && md_flush_request(mddev, bio))
+		return true;
+
+	if (unlikely((bio_op(bio) == REQ_OP_DISCARD))) {
+		raid0_handle_discard(mddev, bio);
+		return true;
+	}
+
+	bio_sector = bio->bi_iter.bi_sector;
+	sector = bio_sector;
+	chunk_sects = mddev->chunk_sectors;
+
+	sectors = chunk_sects -
+		(likely(is_power_of_2(chunk_sects))
+		 ? (sector & (chunk_sects-1))
+		 : sector_div(sector, chunk_sects));
+
+	/* Restore due to sector_div */
+	sector = bio_sector;
+
+	if (sectors < bio_sectors(bio)) {
+		struct bio *split = bio_split(bio, sectors, GFP_NOIO,
+					      &mddev->bio_set);
+		bio_chain(split, bio);
+		submit_bio_noacct(bio);
+		bio = split;
+	}
+
+	if (bio->bi_pool != &mddev->bio_set)
+		md_account_bio(mddev, &bio);
+
+	orig_sector = sector;
+	zone = find_zone(mddev->private, &sector);
+	switch (conf->layout) {
+	case RAID0_ORIG_LAYOUT:
+		tmp_dev = map_sector(mddev, zone, orig_sector, &sector);
+		break;
+	case RAID0_ALT_MULTIZONE_LAYOUT:
+		tmp_dev = map_sector(mddev, zone, sector, &sector);
+		break;
+	default:
+		WARN(1, "md/raid0:%s: Invalid layout\n", mdname(mddev));
+		bio_io_error(bio);
+		return true;
+	}
+
+	if (unlikely(is_mddev_broken(tmp_dev, "raid0"))) {
+		bio_io_error(bio);
+		return true;
+	}
+
+	bio_set_dev(bio, tmp_dev->bdev);
+	bio->bi_iter.bi_sector = sector + zone->dev_start +
+		tmp_dev->data_offset;
+
+	if (mddev->gendisk)
+		trace_block_bio_remap(bio, disk_devt(mddev->gendisk),
+				      bio_sector);
+	mddev_check_write_zeroes(mddev, bio);
+	submit_bio_noacct(bio);
+	return true;
+}
+
+static void raid0_status(struct seq_file *seq, struct mddev *mddev)
+{
+	seq_printf(seq, " %dk chunks", mddev->chunk_sectors / 2);
+	return;
+}
+
+static void *raid0_takeover_raid45(struct mddev *mddev)
+{
+	struct md_rdev *rdev;
+	struct r0conf *priv_conf;
+
+	if (mddev->degraded != 1) {
+		pr_warn("md/raid0:%s: raid5 must be degraded! Degraded disks: %d\n",
+			mdname(mddev),
+			mddev->degraded);
+		return ERR_PTR(-EINVAL);
+	}
+
+	rdev_for_each(rdev, mddev) {
+		/* check slot number for a disk */
+		if (rdev->raid_disk == mddev->raid_disks-1) {
+			pr_warn("md/raid0:%s: raid5 must have missing parity disk!\n",
+				mdname(mddev));
+			return ERR_PTR(-EINVAL);
+		}
+		rdev->sectors = mddev->dev_sectors;
+	}
+
+	/* Set new parameters */
+	mddev->new_level = 0;
+	mddev->new_layout = 0;
+	mddev->new_chunk_sectors = mddev->chunk_sectors;
+	mddev->raid_disks--;
+	mddev->delta_disks = -1;
+	/* make sure it will be not marked as dirty */
+	mddev->recovery_cp = MaxSector;
+	mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS);
+
+	create_strip_zones(mddev, &priv_conf);
+
+	return priv_conf;
+}
+
+static void *raid0_takeover_raid10(struct mddev *mddev)
+{
+	struct r0conf *priv_conf;
+
+	/* Check layout:
+	 *  - far_copies must be 1
+	 *  - near_copies must be 2
+	 *  - disks number must be even
+	 *  - all mirrors must be already degraded
+	 */
+	if (mddev->layout != ((1 << 8) + 2)) {
+		pr_warn("md/raid0:%s:: Raid0 cannot takeover layout: 0x%x\n",
+			mdname(mddev),
+			mddev->layout);
+		return ERR_PTR(-EINVAL);
+	}
+	if (mddev->raid_disks & 1) {
+		pr_warn("md/raid0:%s: Raid0 cannot takeover Raid10 with odd disk number.\n",
+			mdname(mddev));
+		return ERR_PTR(-EINVAL);
+	}
+	if (mddev->degraded != (mddev->raid_disks>>1)) {
+		pr_warn("md/raid0:%s: All mirrors must be already degraded!\n",
+			mdname(mddev));
+		return ERR_PTR(-EINVAL);
+	}
+
+	/* Set new parameters */
+	mddev->new_level = 0;
+	mddev->new_layout = 0;
+	mddev->new_chunk_sectors = mddev->chunk_sectors;
+	mddev->delta_disks = - mddev->raid_disks / 2;
+	mddev->raid_disks += mddev->delta_disks;
+	mddev->degraded = 0;
+	/* make sure it will be not marked as dirty */
+	mddev->recovery_cp = MaxSector;
+	mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS);
+
+	create_strip_zones(mddev, &priv_conf);
+	return priv_conf;
+}
+
+static void *raid0_takeover_raid1(struct mddev *mddev)
+{
+	struct r0conf *priv_conf;
+	int chunksect;
+
+	/* Check layout:
+	 *  - (N - 1) mirror drives must be already faulty
+	 */
+	if ((mddev->raid_disks - 1) != mddev->degraded) {
+		pr_err("md/raid0:%s: (N - 1) mirrors drives must be already faulty!\n",
+		       mdname(mddev));
+		return ERR_PTR(-EINVAL);
+	}
+
+	/*
+	 * a raid1 doesn't have the notion of chunk size, so
+	 * figure out the largest suitable size we can use.
+	 */
+	chunksect = 64 * 2; /* 64K by default */
+
+	/* The array must be an exact multiple of chunksize */
+	while (chunksect && (mddev->array_sectors & (chunksect - 1)))
+		chunksect >>= 1;
+
+	if ((chunksect << 9) < PAGE_SIZE)
+		/* array size does not allow a suitable chunk size */
+		return ERR_PTR(-EINVAL);
+
+	/* Set new parameters */
+	mddev->new_level = 0;
+	mddev->new_layout = 0;
+	mddev->new_chunk_sectors = chunksect;
+	mddev->chunk_sectors = chunksect;
+	mddev->delta_disks = 1 - mddev->raid_disks;
+	mddev->raid_disks = 1;
+	/* make sure it will be not marked as dirty */
+	mddev->recovery_cp = MaxSector;
+	mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS);
+
+	create_strip_zones(mddev, &priv_conf);
+	return priv_conf;
+}
+
+static void *raid0_takeover(struct mddev *mddev)
+{
+	/* raid0 can take over:
+	 *  raid4 - if all data disks are active.
+	 *  raid5 - providing it is Raid4 layout and one disk is faulty
+	 *  raid10 - assuming we have all necessary active disks
+	 *  raid1 - with (N -1) mirror drives faulty
+	 */
+
+	if (mddev->bitmap) {
+		pr_warn("md/raid0: %s: cannot takeover array with bitmap\n",
+			mdname(mddev));
+		return ERR_PTR(-EBUSY);
+	}
+	if (mddev->level == 4)
+		return raid0_takeover_raid45(mddev);
+
+	if (mddev->level == 5) {
+		if (mddev->layout == ALGORITHM_PARITY_N)
+			return raid0_takeover_raid45(mddev);
+
+		pr_warn("md/raid0:%s: Raid can only takeover Raid5 with layout: %d\n",
+			mdname(mddev), ALGORITHM_PARITY_N);
+	}
+
+	if (mddev->level == 10)
+		return raid0_takeover_raid10(mddev);
+
+	if (mddev->level == 1)
+		return raid0_takeover_raid1(mddev);
+
+	pr_warn("Takeover from raid%i to raid0 not supported\n",
+		mddev->level);
+
+	return ERR_PTR(-EINVAL);
+}
+
+static void raid0_quiesce(struct mddev *mddev, int quiesce)
+{
+}
+
+static struct md_personality raid0_personality=
+{
+	.name		= "raid0",
+	.level		= 0,
+	.owner		= THIS_MODULE,
+	.make_request	= raid0_make_request,
+	.run		= raid0_run,
+	.free		= raid0_free,
+	.status		= raid0_status,
+	.size		= raid0_size,
+	.takeover	= raid0_takeover,
+	.quiesce	= raid0_quiesce,
+};
+
+static int __init raid0_init (void)
+{
+	return register_md_personality (&raid0_personality);
+}
+
+static void raid0_exit (void)
+{
+	unregister_md_personality (&raid0_personality);
+}
+
+module_init(raid0_init);
+module_exit(raid0_exit);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("RAID0 (striping) personality for MD");
+MODULE_ALIAS("md-personality-2"); /* RAID0 */
+MODULE_ALIAS("md-raid0");
+MODULE_ALIAS("md-level-0");