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, 950 insertions, 0 deletions

diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
new file mode 100644
index 000000000..ce0e000b7
--- /dev/null
+++ b/drivers/target/target_core_file.c
@@ -0,0 +1,950 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ * Filename:  target_core_file.c
+ *
+ * This file contains the Storage Engine <-> FILEIO transport specific functions
+ *
+ * (c) Copyright 2005-2013 Datera, Inc.
+ *
+ * Nicholas A. Bellinger <nab@kernel.org>
+ *
+ ******************************************************************************/
+
+#include <linux/string.h>
+#include <linux/parser.h>
+#include <linux/timer.h>
+#include <linux/blkdev.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/falloc.h>
+#include <linux/uio.h>
+#include <linux/scatterlist.h>
+#include <scsi/scsi_proto.h>
+#include <asm/unaligned.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_backend.h>
+
+#include "target_core_file.h"
+
+static inline struct fd_dev *FD_DEV(struct se_device *dev)
+{
+	return container_of(dev, struct fd_dev, dev);
+}
+
+static int fd_attach_hba(struct se_hba *hba, u32 host_id)
+{
+	struct fd_host *fd_host;
+
+	fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
+	if (!fd_host) {
+		pr_err("Unable to allocate memory for struct fd_host\n");
+		return -ENOMEM;
+	}
+
+	fd_host->fd_host_id = host_id;
+
+	hba->hba_ptr = fd_host;
+
+	pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
+		" Target Core Stack %s\n", hba->hba_id, FD_VERSION,
+		TARGET_CORE_VERSION);
+	pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n",
+		hba->hba_id, fd_host->fd_host_id);
+
+	return 0;
+}
+
+static void fd_detach_hba(struct se_hba *hba)
+{
+	struct fd_host *fd_host = hba->hba_ptr;
+
+	pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
+		" Target Core\n", hba->hba_id, fd_host->fd_host_id);
+
+	kfree(fd_host);
+	hba->hba_ptr = NULL;
+}
+
+static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name)
+{
+	struct fd_dev *fd_dev;
+	struct fd_host *fd_host = hba->hba_ptr;
+
+	fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
+	if (!fd_dev) {
+		pr_err("Unable to allocate memory for struct fd_dev\n");
+		return NULL;
+	}
+
+	fd_dev->fd_host = fd_host;
+
+	pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
+
+	return &fd_dev->dev;
+}
+
+static bool fd_configure_unmap(struct se_device *dev)
+{
+	struct file *file = FD_DEV(dev)->fd_file;
+	struct inode *inode = file->f_mapping->host;
+
+	if (S_ISBLK(inode->i_mode))
+		return target_configure_unmap_from_queue(&dev->dev_attrib,
+							 I_BDEV(inode));
+
+	/* Limit UNMAP emulation to 8k Number of LBAs (NoLB) */
+	dev->dev_attrib.max_unmap_lba_count = 0x2000;
+	/* Currently hardcoded to 1 in Linux/SCSI code. */
+	dev->dev_attrib.max_unmap_block_desc_count = 1;
+	dev->dev_attrib.unmap_granularity = 1;
+	dev->dev_attrib.unmap_granularity_alignment = 0;
+	return true;
+}
+
+static int fd_configure_device(struct se_device *dev)
+{
+	struct fd_dev *fd_dev = FD_DEV(dev);
+	struct fd_host *fd_host = dev->se_hba->hba_ptr;
+	struct file *file;
+	struct inode *inode = NULL;
+	int flags, ret = -EINVAL;
+
+	if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
+		pr_err("Missing fd_dev_name=\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Use O_DSYNC by default instead of O_SYNC to forgo syncing
+	 * of pure timestamp updates.
+	 */
+	flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
+
+	/*
+	 * Optionally allow fd_buffered_io=1 to be enabled for people
+	 * who want use the fs buffer cache as an WriteCache mechanism.
+	 *
+	 * This means that in event of a hard failure, there is a risk
+	 * of silent data-loss if the SCSI client has *not* performed a
+	 * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
+	 * to write-out the entire device cache.
+	 */
+	if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
+		pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
+		flags &= ~O_DSYNC;
+	}
+
+	file = filp_open(fd_dev->fd_dev_name, flags, 0600);
+	if (IS_ERR(file)) {
+		pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
+		ret = PTR_ERR(file);
+		goto fail;
+	}
+	fd_dev->fd_file = file;
+	/*
+	 * If using a block backend with this struct file, we extract
+	 * fd_dev->fd_[block,dev]_size from struct block_device.
+	 *
+	 * Otherwise, we use the passed fd_size= from configfs
+	 */
+	inode = file->f_mapping->host;
+	if (S_ISBLK(inode->i_mode)) {
+		struct block_device *bdev = I_BDEV(inode);
+		unsigned long long dev_size;
+
+		fd_dev->fd_block_size = bdev_logical_block_size(bdev);
+		/*
+		 * Determine the number of bytes from i_size_read() minus
+		 * one (1) logical sector from underlying struct block_device
+		 */
+		dev_size = (i_size_read(file->f_mapping->host) -
+				       fd_dev->fd_block_size);
+
+		pr_debug("FILEIO: Using size: %llu bytes from struct"
+			" block_device blocks: %llu logical_block_size: %d\n",
+			dev_size, div_u64(dev_size, fd_dev->fd_block_size),
+			fd_dev->fd_block_size);
+		/*
+		 * Enable write same emulation for IBLOCK and use 0xFFFF as
+		 * the smaller WRITE_SAME(10) only has a two-byte block count.
+		 */
+		dev->dev_attrib.max_write_same_len = 0xFFFF;
+
+		if (bdev_nonrot(bdev))
+			dev->dev_attrib.is_nonrot = 1;
+	} else {
+		if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
+			pr_err("FILEIO: Missing fd_dev_size="
+				" parameter, and no backing struct"
+				" block_device\n");
+			goto fail;
+		}
+
+		fd_dev->fd_block_size = FD_BLOCKSIZE;
+
+		/*
+		 * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
+		 * based upon struct iovec limit for vfs_writev()
+		 */
+		dev->dev_attrib.max_write_same_len = 0x1000;
+	}
+
+	dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
+	dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
+	dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
+
+	if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
+		pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
+			" with FDBD_HAS_BUFFERED_IO_WCE\n");
+		dev->dev_attrib.emulate_write_cache = 1;
+	}
+
+	fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
+	fd_dev->fd_queue_depth = dev->queue_depth;
+
+	pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
+		" %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
+			fd_dev->fd_dev_name, fd_dev->fd_dev_size);
+
+	return 0;
+fail:
+	if (fd_dev->fd_file) {
+		filp_close(fd_dev->fd_file, NULL);
+		fd_dev->fd_file = NULL;
+	}
+	return ret;
+}
+
+static void fd_dev_call_rcu(struct rcu_head *p)
+{
+	struct se_device *dev = container_of(p, struct se_device, rcu_head);
+	struct fd_dev *fd_dev = FD_DEV(dev);
+
+	kfree(fd_dev);
+}
+
+static void fd_free_device(struct se_device *dev)
+{
+	call_rcu(&dev->rcu_head, fd_dev_call_rcu);
+}
+
+static void fd_destroy_device(struct se_device *dev)
+{
+	struct fd_dev *fd_dev = FD_DEV(dev);
+
+	if (fd_dev->fd_file) {
+		filp_close(fd_dev->fd_file, NULL);
+		fd_dev->fd_file = NULL;
+	}
+}
+
+struct target_core_file_cmd {
+	unsigned long	len;
+	struct se_cmd	*cmd;
+	struct kiocb	iocb;
+	struct bio_vec	bvecs[];
+};
+
+static void cmd_rw_aio_complete(struct kiocb *iocb, long ret)
+{
+	struct target_core_file_cmd *cmd;
+
+	cmd = container_of(iocb, struct target_core_file_cmd, iocb);
+
+	if (ret != cmd->len)
+		target_complete_cmd(cmd->cmd, SAM_STAT_CHECK_CONDITION);
+	else
+		target_complete_cmd(cmd->cmd, SAM_STAT_GOOD);
+
+	kfree(cmd);
+}
+
+static sense_reason_t
+fd_execute_rw_aio(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
+	      enum dma_data_direction data_direction)
+{
+	int is_write = !(data_direction == DMA_FROM_DEVICE);
+	struct se_device *dev = cmd->se_dev;
+	struct fd_dev *fd_dev = FD_DEV(dev);
+	struct file *file = fd_dev->fd_file;
+	struct target_core_file_cmd *aio_cmd;
+	struct iov_iter iter;
+	struct scatterlist *sg;
+	ssize_t len = 0;
+	int ret = 0, i;
+
+	aio_cmd = kmalloc(struct_size(aio_cmd, bvecs, sgl_nents), GFP_KERNEL);
+	if (!aio_cmd)
+		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+	for_each_sg(sgl, sg, sgl_nents, i) {
+		bvec_set_page(&aio_cmd->bvecs[i], sg_page(sg), sg->length,
+			      sg->offset);
+		len += sg->length;
+	}
+
+	iov_iter_bvec(&iter, is_write, aio_cmd->bvecs, sgl_nents, len);
+
+	aio_cmd->cmd = cmd;
+	aio_cmd->len = len;
+	aio_cmd->iocb.ki_pos = cmd->t_task_lba * dev->dev_attrib.block_size;
+	aio_cmd->iocb.ki_filp = file;
+	aio_cmd->iocb.ki_complete = cmd_rw_aio_complete;
+	aio_cmd->iocb.ki_flags = IOCB_DIRECT;
+
+	if (is_write && (cmd->se_cmd_flags & SCF_FUA))
+		aio_cmd->iocb.ki_flags |= IOCB_DSYNC;
+
+	if (is_write)
+		ret = call_write_iter(file, &aio_cmd->iocb, &iter);
+	else
+		ret = call_read_iter(file, &aio_cmd->iocb, &iter);
+
+	if (ret != -EIOCBQUEUED)
+		cmd_rw_aio_complete(&aio_cmd->iocb, ret);
+
+	return 0;
+}
+
+static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
+		    u32 block_size, struct scatterlist *sgl,
+		    u32 sgl_nents, u32 data_length, int is_write)
+{
+	struct scatterlist *sg;
+	struct iov_iter iter;
+	struct bio_vec *bvec;
+	ssize_t len = 0;
+	loff_t pos = (cmd->t_task_lba * block_size);
+	int ret = 0, i;
+
+	bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
+	if (!bvec) {
+		pr_err("Unable to allocate fd_do_readv iov[]\n");
+		return -ENOMEM;
+	}
+
+	for_each_sg(sgl, sg, sgl_nents, i) {
+		bvec_set_page(&bvec[i], sg_page(sg), sg->length, sg->offset);
+		len += sg->length;
+	}
+
+	iov_iter_bvec(&iter, is_write, bvec, sgl_nents, len);
+	if (is_write)
+		ret = vfs_iter_write(fd, &iter, &pos, 0);
+	else
+		ret = vfs_iter_read(fd, &iter, &pos, 0);
+
+	if (is_write) {
+		if (ret < 0 || ret != data_length) {
+			pr_err("%s() write returned %d\n", __func__, ret);
+			if (ret >= 0)
+				ret = -EINVAL;
+		}
+	} else {
+		/*
+		 * Return zeros and GOOD status even if the READ did not return
+		 * the expected virt_size for struct file w/o a backing struct
+		 * block_device.
+		 */
+		if (S_ISBLK(file_inode(fd)->i_mode)) {
+			if (ret < 0 || ret != data_length) {
+				pr_err("%s() returned %d, expecting %u for "
+						"S_ISBLK\n", __func__, ret,
+						data_length);
+				if (ret >= 0)
+					ret = -EINVAL;
+			}
+		} else {
+			if (ret < 0) {
+				pr_err("%s() returned %d for non S_ISBLK\n",
+						__func__, ret);
+			} else if (ret != data_length) {
+				/*
+				 * Short read case:
+				 * Probably some one truncate file under us.
+				 * We must explicitly zero sg-pages to prevent
+				 * expose uninizialized pages to userspace.
+				 */
+				if (ret < data_length)
+					ret += iov_iter_zero(data_length - ret, &iter);
+				else
+					ret = -EINVAL;
+			}
+		}
+	}
+	kfree(bvec);
+	return ret;
+}
+
+static sense_reason_t
+fd_execute_sync_cache(struct se_cmd *cmd)
+{
+	struct se_device *dev = cmd->se_dev;
+	struct fd_dev *fd_dev = FD_DEV(dev);
+	int immed = (cmd->t_task_cdb[1] & 0x2);
+	loff_t start, end;
+	int ret;
+
+	/*
+	 * If the Immediate bit is set, queue up the GOOD response
+	 * for this SYNCHRONIZE_CACHE op
+	 */
+	if (immed)
+		target_complete_cmd(cmd, SAM_STAT_GOOD);
+
+	/*
+	 * Determine if we will be flushing the entire device.
+	 */
+	if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
+		start = 0;
+		end = LLONG_MAX;
+	} else {
+		start = cmd->t_task_lba * dev->dev_attrib.block_size;
+		if (cmd->data_length)
+			end = start + cmd->data_length - 1;
+		else
+			end = LLONG_MAX;
+	}
+
+	ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
+	if (ret != 0)
+		pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
+
+	if (immed)
+		return 0;
+
+	if (ret)
+		target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
+	else
+		target_complete_cmd(cmd, SAM_STAT_GOOD);
+
+	return 0;
+}
+
+static sense_reason_t
+fd_execute_write_same(struct se_cmd *cmd)
+{
+	struct se_device *se_dev = cmd->se_dev;
+	struct fd_dev *fd_dev = FD_DEV(se_dev);
+	loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
+	sector_t nolb = sbc_get_write_same_sectors(cmd);
+	struct iov_iter iter;
+	struct bio_vec *bvec;
+	unsigned int len = 0, i;
+	ssize_t ret;
+
+	if (cmd->prot_op) {
+		pr_err("WRITE_SAME: Protection information with FILEIO"
+		       " backends not supported\n");
+		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+	}
+
+	if (!cmd->t_data_nents)
+		return TCM_INVALID_CDB_FIELD;
+
+	if (cmd->t_data_nents > 1 ||
+	    cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
+		pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
+			" block_size: %u\n",
+			cmd->t_data_nents,
+			cmd->t_data_sg[0].length,
+			cmd->se_dev->dev_attrib.block_size);
+		return TCM_INVALID_CDB_FIELD;
+	}
+
+	bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
+	if (!bvec)
+		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+	for (i = 0; i < nolb; i++) {
+		bvec_set_page(&bvec[i], sg_page(&cmd->t_data_sg[0]),
+			      cmd->t_data_sg[0].length,
+			      cmd->t_data_sg[0].offset);
+		len += se_dev->dev_attrib.block_size;
+	}
+
+	iov_iter_bvec(&iter, ITER_SOURCE, bvec, nolb, len);
+	ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0);
+
+	kfree(bvec);
+	if (ret < 0 || ret != len) {
+		pr_err("vfs_iter_write() returned %zd for write same\n", ret);
+		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+	}
+
+	target_complete_cmd(cmd, SAM_STAT_GOOD);
+	return 0;
+}
+
+static int
+fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
+		void *buf, size_t bufsize)
+{
+	struct fd_dev *fd_dev = FD_DEV(se_dev);
+	struct file *prot_fd = fd_dev->fd_prot_file;
+	sector_t prot_length, prot;
+	loff_t pos = lba * se_dev->prot_length;
+
+	if (!prot_fd) {
+		pr_err("Unable to locate fd_dev->fd_prot_file\n");
+		return -ENODEV;
+	}
+
+	prot_length = nolb * se_dev->prot_length;
+
+	memset(buf, 0xff, bufsize);
+	for (prot = 0; prot < prot_length;) {
+		sector_t len = min_t(sector_t, bufsize, prot_length - prot);
+		ssize_t ret = kernel_write(prot_fd, buf, len, &pos);
+
+		if (ret != len) {
+			pr_err("vfs_write to prot file failed: %zd\n", ret);
+			return ret < 0 ? ret : -ENODEV;
+		}
+		prot += ret;
+	}
+
+	return 0;
+}
+
+static int
+fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
+{
+	void *buf;
+	int rc;
+
+	buf = (void *)__get_free_page(GFP_KERNEL);
+	if (!buf) {
+		pr_err("Unable to allocate FILEIO prot buf\n");
+		return -ENOMEM;
+	}
+
+	rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
+
+	free_page((unsigned long)buf);
+
+	return rc;
+}
+
+static sense_reason_t
+fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
+{
+	struct file *file = FD_DEV(cmd->se_dev)->fd_file;
+	struct inode *inode = file->f_mapping->host;
+	int ret;
+
+	if (!nolb) {
+		return 0;
+	}
+
+	if (cmd->se_dev->dev_attrib.pi_prot_type) {
+		ret = fd_do_prot_unmap(cmd, lba, nolb);
+		if (ret)
+			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+	}
+
+	if (S_ISBLK(inode->i_mode)) {
+		/* The backend is block device, use discard */
+		struct block_device *bdev = I_BDEV(inode);
+		struct se_device *dev = cmd->se_dev;
+
+		ret = blkdev_issue_discard(bdev,
+					   target_to_linux_sector(dev, lba),
+					   target_to_linux_sector(dev,  nolb),
+					   GFP_KERNEL);
+		if (ret < 0) {
+			pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
+				ret);
+			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		}
+	} else {
+		/* The backend is normal file, use fallocate */
+		struct se_device *se_dev = cmd->se_dev;
+		loff_t pos = lba * se_dev->dev_attrib.block_size;
+		unsigned int len = nolb * se_dev->dev_attrib.block_size;
+		int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
+
+		if (!file->f_op->fallocate)
+			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+		ret = file->f_op->fallocate(file, mode, pos, len);
+		if (ret < 0) {
+			pr_warn("FILEIO: fallocate() failed: %d\n", ret);
+			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		}
+	}
+
+	return 0;
+}
+
+static sense_reason_t
+fd_execute_rw_buffered(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
+	      enum dma_data_direction data_direction)
+{
+	struct se_device *dev = cmd->se_dev;
+	struct fd_dev *fd_dev = FD_DEV(dev);
+	struct file *file = fd_dev->fd_file;
+	struct file *pfile = fd_dev->fd_prot_file;
+	sense_reason_t rc;
+	int ret = 0;
+	/*
+	 * Call vectorized fileio functions to map struct scatterlist
+	 * physical memory addresses to struct iovec virtual memory.
+	 */
+	if (data_direction == DMA_FROM_DEVICE) {
+		if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
+			ret = fd_do_rw(cmd, pfile, dev->prot_length,
+				       cmd->t_prot_sg, cmd->t_prot_nents,
+				       cmd->prot_length, 0);
+			if (ret < 0)
+				return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		}
+
+		ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
+			       sgl, sgl_nents, cmd->data_length, 0);
+
+		if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type &&
+		    dev->dev_attrib.pi_prot_verify) {
+			u32 sectors = cmd->data_length >>
+					ilog2(dev->dev_attrib.block_size);
+
+			rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
+					    0, cmd->t_prot_sg, 0);
+			if (rc)
+				return rc;
+		}
+	} else {
+		if (cmd->prot_type && dev->dev_attrib.pi_prot_type &&
+		    dev->dev_attrib.pi_prot_verify) {
+			u32 sectors = cmd->data_length >>
+					ilog2(dev->dev_attrib.block_size);
+
+			rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
+					    0, cmd->t_prot_sg, 0);
+			if (rc)
+				return rc;
+		}
+
+		ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
+			       sgl, sgl_nents, cmd->data_length, 1);
+		/*
+		 * Perform implicit vfs_fsync_range() for fd_do_writev() ops
+		 * for SCSI WRITEs with Forced Unit Access (FUA) set.
+		 * Allow this to happen independent of WCE=0 setting.
+		 */
+		if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
+			loff_t start = cmd->t_task_lba *
+				dev->dev_attrib.block_size;
+			loff_t end;
+
+			if (cmd->data_length)
+				end = start + cmd->data_length - 1;
+			else
+				end = LLONG_MAX;
+
+			vfs_fsync_range(fd_dev->fd_file, start, end, 1);
+		}
+
+		if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
+			ret = fd_do_rw(cmd, pfile, dev->prot_length,
+				       cmd->t_prot_sg, cmd->t_prot_nents,
+				       cmd->prot_length, 1);
+			if (ret < 0)
+				return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		}
+	}
+
+	if (ret < 0)
+		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+	target_complete_cmd(cmd, SAM_STAT_GOOD);
+	return 0;
+}
+
+static sense_reason_t
+fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
+	      enum dma_data_direction data_direction)
+{
+	struct se_device *dev = cmd->se_dev;
+	struct fd_dev *fd_dev = FD_DEV(dev);
+
+	/*
+	 * We are currently limited by the number of iovecs (2048) per
+	 * single vfs_[writev,readv] call.
+	 */
+	if (cmd->data_length > FD_MAX_BYTES) {
+		pr_err("FILEIO: Not able to process I/O of %u bytes due to"
+		       "FD_MAX_BYTES: %u iovec count limitation\n",
+			cmd->data_length, FD_MAX_BYTES);
+		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+	}
+
+	if (fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO)
+		return fd_execute_rw_aio(cmd, sgl, sgl_nents, data_direction);
+	return fd_execute_rw_buffered(cmd, sgl, sgl_nents, data_direction);
+}
+
+enum {
+	Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io,
+	Opt_fd_async_io, Opt_err
+};
+
+static match_table_t tokens = {
+	{Opt_fd_dev_name, "fd_dev_name=%s"},
+	{Opt_fd_dev_size, "fd_dev_size=%s"},
+	{Opt_fd_buffered_io, "fd_buffered_io=%d"},
+	{Opt_fd_async_io, "fd_async_io=%d"},
+	{Opt_err, NULL}
+};
+
+static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
+		const char *page, ssize_t count)
+{
+	struct fd_dev *fd_dev = FD_DEV(dev);
+	char *orig, *ptr, *arg_p, *opts;
+	substring_t args[MAX_OPT_ARGS];
+	int ret = 0, arg, token;
+
+	opts = kstrdup(page, GFP_KERNEL);
+	if (!opts)
+		return -ENOMEM;
+
+	orig = opts;
+
+	while ((ptr = strsep(&opts, ",\n")) != NULL) {
+		if (!*ptr)
+			continue;
+
+		token = match_token(ptr, tokens, args);
+		switch (token) {
+		case Opt_fd_dev_name:
+			if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
+				FD_MAX_DEV_NAME) == 0) {
+				ret = -EINVAL;
+				break;
+			}
+			pr_debug("FILEIO: Referencing Path: %s\n",
+					fd_dev->fd_dev_name);
+			fd_dev->fbd_flags |= FBDF_HAS_PATH;
+			break;
+		case Opt_fd_dev_size:
+			arg_p = match_strdup(&args[0]);
+			if (!arg_p) {
+				ret = -ENOMEM;
+				break;
+			}
+			ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
+			kfree(arg_p);
+			if (ret < 0) {
+				pr_err("kstrtoull() failed for"
+						" fd_dev_size=\n");
+				goto out;
+			}
+			pr_debug("FILEIO: Referencing Size: %llu"
+					" bytes\n", fd_dev->fd_dev_size);
+			fd_dev->fbd_flags |= FBDF_HAS_SIZE;
+			break;
+		case Opt_fd_buffered_io:
+			ret = match_int(args, &arg);
+			if (ret)
+				goto out;
+			if (arg != 1) {
+				pr_err("bogus fd_buffered_io=%d value\n", arg);
+				ret = -EINVAL;
+				goto out;
+			}
+
+			pr_debug("FILEIO: Using buffered I/O"
+				" operations for struct fd_dev\n");
+
+			fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
+			break;
+		case Opt_fd_async_io:
+			ret = match_int(args, &arg);
+			if (ret)
+				goto out;
+			if (arg != 1) {
+				pr_err("bogus fd_async_io=%d value\n", arg);
+				ret = -EINVAL;
+				goto out;
+			}
+
+			pr_debug("FILEIO: Using async I/O"
+				" operations for struct fd_dev\n");
+
+			fd_dev->fbd_flags |= FDBD_HAS_ASYNC_IO;
+			break;
+		default:
+			break;
+		}
+	}
+
+out:
+	kfree(orig);
+	return (!ret) ? count : ret;
+}
+
+static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
+{
+	struct fd_dev *fd_dev = FD_DEV(dev);
+	ssize_t bl = 0;
+
+	bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
+	bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s Async: %d\n",
+		fd_dev->fd_dev_name, fd_dev->fd_dev_size,
+		(fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
+		"Buffered-WCE" : "O_DSYNC",
+		!!(fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO));
+	return bl;
+}
+
+static sector_t fd_get_blocks(struct se_device *dev)
+{
+	struct fd_dev *fd_dev = FD_DEV(dev);
+	struct file *f = fd_dev->fd_file;
+	struct inode *i = f->f_mapping->host;
+	unsigned long long dev_size;
+	/*
+	 * When using a file that references an underlying struct block_device,
+	 * ensure dev_size is always based on the current inode size in order
+	 * to handle underlying block_device resize operations.
+	 */
+	if (S_ISBLK(i->i_mode))
+		dev_size = i_size_read(i);
+	else
+		dev_size = fd_dev->fd_dev_size;
+
+	return div_u64(dev_size - dev->dev_attrib.block_size,
+		       dev->dev_attrib.block_size);
+}
+
+static int fd_init_prot(struct se_device *dev)
+{
+	struct fd_dev *fd_dev = FD_DEV(dev);
+	struct file *prot_file, *file = fd_dev->fd_file;
+	struct inode *inode;
+	int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
+	char buf[FD_MAX_DEV_PROT_NAME];
+
+	if (!file) {
+		pr_err("Unable to locate fd_dev->fd_file\n");
+		return -ENODEV;
+	}
+
+	inode = file->f_mapping->host;
+	if (S_ISBLK(inode->i_mode)) {
+		pr_err("FILEIO Protection emulation only supported on"
+		       " !S_ISBLK\n");
+		return -ENOSYS;
+	}
+
+	if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
+		flags &= ~O_DSYNC;
+
+	snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
+		 fd_dev->fd_dev_name);
+
+	prot_file = filp_open(buf, flags, 0600);
+	if (IS_ERR(prot_file)) {
+		pr_err("filp_open(%s) failed\n", buf);
+		ret = PTR_ERR(prot_file);
+		return ret;
+	}
+	fd_dev->fd_prot_file = prot_file;
+
+	return 0;
+}
+
+static int fd_format_prot(struct se_device *dev)
+{
+	unsigned char *buf;
+	int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
+	int ret;
+
+	if (!dev->dev_attrib.pi_prot_type) {
+		pr_err("Unable to format_prot while pi_prot_type == 0\n");
+		return -ENODEV;
+	}
+
+	buf = vzalloc(unit_size);
+	if (!buf) {
+		pr_err("Unable to allocate FILEIO prot buf\n");
+		return -ENOMEM;
+	}
+
+	pr_debug("Using FILEIO prot_length: %llu\n",
+		 (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
+					dev->prot_length);
+
+	ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
+			      buf, unit_size);
+	vfree(buf);
+	return ret;
+}
+
+static void fd_free_prot(struct se_device *dev)
+{
+	struct fd_dev *fd_dev = FD_DEV(dev);
+
+	if (!fd_dev->fd_prot_file)
+		return;
+
+	filp_close(fd_dev->fd_prot_file, NULL);
+	fd_dev->fd_prot_file = NULL;
+}
+
+static struct sbc_ops fd_sbc_ops = {
+	.execute_rw		= fd_execute_rw,
+	.execute_sync_cache	= fd_execute_sync_cache,
+	.execute_write_same	= fd_execute_write_same,
+	.execute_unmap		= fd_execute_unmap,
+};
+
+static sense_reason_t
+fd_parse_cdb(struct se_cmd *cmd)
+{
+	return sbc_parse_cdb(cmd, &fd_sbc_ops);
+}
+
+static const struct target_backend_ops fileio_ops = {
+	.name			= "fileio",
+	.inquiry_prod		= "FILEIO",
+	.inquiry_rev		= FD_VERSION,
+	.owner			= THIS_MODULE,
+	.attach_hba		= fd_attach_hba,
+	.detach_hba		= fd_detach_hba,
+	.alloc_device		= fd_alloc_device,
+	.configure_device	= fd_configure_device,
+	.destroy_device		= fd_destroy_device,
+	.free_device		= fd_free_device,
+	.configure_unmap	= fd_configure_unmap,
+	.parse_cdb		= fd_parse_cdb,
+	.set_configfs_dev_params = fd_set_configfs_dev_params,
+	.show_configfs_dev_params = fd_show_configfs_dev_params,
+	.get_device_type	= sbc_get_device_type,
+	.get_blocks		= fd_get_blocks,
+	.init_prot		= fd_init_prot,
+	.format_prot		= fd_format_prot,
+	.free_prot		= fd_free_prot,
+	.tb_dev_attrib_attrs	= sbc_attrib_attrs,
+};
+
+static int __init fileio_module_init(void)
+{
+	return transport_backend_register(&fileio_ops);
+}
+
+static void __exit fileio_module_exit(void)
+{
+	target_backend_unregister(&fileio_ops);
+}
+
+MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
+MODULE_AUTHOR("nab@Linux-iSCSI.org");
+MODULE_LICENSE("GPL");
+
+module_init(fileio_module_init);
+module_exit(fileio_module_exit);