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, 566 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/powernv/opal-flash.c b/arch/powerpc/platforms/powernv/opal-flash.c
new file mode 100644
index 000000000..d5ea04e8e
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opal-flash.c
@@ -0,0 +1,566 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PowerNV OPAL Firmware Update Interface
+ *
+ * Copyright 2013 IBM Corp.
+ */
+
+#define DEBUG
+
+#include <linux/kernel.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/kobject.h>
+#include <linux/sysfs.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/delay.h>
+
+#include <asm/opal.h>
+
+/* FLASH status codes */
+#define FLASH_NO_OP		-1099	/* No operation initiated by user */
+#define FLASH_NO_AUTH		-9002	/* Not a service authority partition */
+
+/* Validate image status values */
+#define VALIDATE_IMG_READY	-1001	/* Image ready for validation */
+#define VALIDATE_IMG_INCOMPLETE	-1002	/* User copied < VALIDATE_BUF_SIZE */
+
+/* Manage image status values */
+#define MANAGE_ACTIVE_ERR	-9001	/* Cannot overwrite active img */
+
+/* Flash image status values */
+#define FLASH_IMG_READY		0	/* Img ready for flash on reboot */
+#define FLASH_INVALID_IMG	-1003	/* Flash image shorter than expected */
+#define FLASH_IMG_NULL_DATA	-1004	/* Bad data in sg list entry */
+#define FLASH_IMG_BAD_LEN	-1005	/* Bad length in sg list entry */
+
+/* Manage operation tokens */
+#define FLASH_REJECT_TMP_SIDE	0	/* Reject temporary fw image */
+#define FLASH_COMMIT_TMP_SIDE	1	/* Commit temporary fw image */
+
+/* Update tokens */
+#define FLASH_UPDATE_CANCEL	0	/* Cancel update request */
+#define FLASH_UPDATE_INIT	1	/* Initiate update */
+
+/* Validate image update result tokens */
+#define VALIDATE_TMP_UPDATE	0     /* T side will be updated */
+#define VALIDATE_FLASH_AUTH	1     /* Partition does not have authority */
+#define VALIDATE_INVALID_IMG	2     /* Candidate image is not valid */
+#define VALIDATE_CUR_UNKNOWN	3     /* Current fixpack level is unknown */
+/*
+ * Current T side will be committed to P side before being replace with new
+ * image, and the new image is downlevel from current image
+ */
+#define VALIDATE_TMP_COMMIT_DL	4
+/*
+ * Current T side will be committed to P side before being replaced with new
+ * image
+ */
+#define VALIDATE_TMP_COMMIT	5
+/*
+ * T side will be updated with a downlevel image
+ */
+#define VALIDATE_TMP_UPDATE_DL	6
+/*
+ * The candidate image's release date is later than the system's firmware
+ * service entitlement date - service warranty period has expired
+ */
+#define VALIDATE_OUT_OF_WRNTY	7
+
+/* Validate buffer size */
+#define VALIDATE_BUF_SIZE	4096
+
+/* XXX: Assume candidate image size is <= 1GB */
+#define MAX_IMAGE_SIZE	0x40000000
+
+/* Image status */
+enum {
+	IMAGE_INVALID,
+	IMAGE_LOADING,
+	IMAGE_READY,
+};
+
+/* Candidate image data */
+struct image_data_t {
+	int		status;
+	void		*data;
+	uint32_t	size;
+};
+
+/* Candidate image header */
+struct image_header_t {
+	uint16_t	magic;
+	uint16_t	version;
+	uint32_t	size;
+};
+
+struct validate_flash_t {
+	int		status;		/* Return status */
+	void		*buf;		/* Candidate image buffer */
+	uint32_t	buf_size;	/* Image size */
+	uint32_t	result;		/* Update results token */
+};
+
+struct manage_flash_t {
+	int status;		/* Return status */
+};
+
+struct update_flash_t {
+	int status;		/* Return status */
+};
+
+static struct image_header_t	image_header;
+static struct image_data_t	image_data;
+static struct validate_flash_t	validate_flash_data;
+static struct manage_flash_t	manage_flash_data;
+
+/* Initialize update_flash_data status to No Operation */
+static struct update_flash_t	update_flash_data = {
+	.status = FLASH_NO_OP,
+};
+
+static DEFINE_MUTEX(image_data_mutex);
+
+/*
+ * Validate candidate image
+ */
+static inline void opal_flash_validate(void)
+{
+	long ret;
+	void *buf = validate_flash_data.buf;
+	__be32 size = cpu_to_be32(validate_flash_data.buf_size);
+	__be32 result;
+
+	ret = opal_validate_flash(__pa(buf), &size, &result);
+
+	validate_flash_data.status = ret;
+	validate_flash_data.buf_size = be32_to_cpu(size);
+	validate_flash_data.result = be32_to_cpu(result);
+}
+
+/*
+ * Validate output format:
+ *     validate result token
+ *     current image version details
+ *     new image version details
+ */
+static ssize_t validate_show(struct kobject *kobj,
+			     struct kobj_attribute *attr, char *buf)
+{
+	struct validate_flash_t *args_buf = &validate_flash_data;
+	int len;
+
+	/* Candidate image is not validated */
+	if (args_buf->status < VALIDATE_TMP_UPDATE) {
+		len = sprintf(buf, "%d\n", args_buf->status);
+		goto out;
+	}
+
+	/* Result token */
+	len = sprintf(buf, "%d\n", args_buf->result);
+
+	/* Current and candidate image version details */
+	if ((args_buf->result != VALIDATE_TMP_UPDATE) &&
+	    (args_buf->result < VALIDATE_CUR_UNKNOWN))
+		goto out;
+
+	if (args_buf->buf_size > (VALIDATE_BUF_SIZE - len)) {
+		memcpy(buf + len, args_buf->buf, VALIDATE_BUF_SIZE - len);
+		len = VALIDATE_BUF_SIZE;
+	} else {
+		memcpy(buf + len, args_buf->buf, args_buf->buf_size);
+		len += args_buf->buf_size;
+	}
+out:
+	/* Set status to default */
+	args_buf->status = FLASH_NO_OP;
+	return len;
+}
+
+/*
+ * Validate candidate firmware image
+ *
+ * Note:
+ *   We are only interested in first 4K bytes of the
+ *   candidate image.
+ */
+static ssize_t validate_store(struct kobject *kobj,
+			      struct kobj_attribute *attr,
+			      const char *buf, size_t count)
+{
+	struct validate_flash_t *args_buf = &validate_flash_data;
+
+	if (buf[0] != '1')
+		return -EINVAL;
+
+	mutex_lock(&image_data_mutex);
+
+	if (image_data.status != IMAGE_READY ||
+	    image_data.size < VALIDATE_BUF_SIZE) {
+		args_buf->result = VALIDATE_INVALID_IMG;
+		args_buf->status = VALIDATE_IMG_INCOMPLETE;
+		goto out;
+	}
+
+	/* Copy first 4k bytes of candidate image */
+	memcpy(args_buf->buf, image_data.data, VALIDATE_BUF_SIZE);
+
+	args_buf->status = VALIDATE_IMG_READY;
+	args_buf->buf_size = VALIDATE_BUF_SIZE;
+
+	/* Validate candidate image */
+	opal_flash_validate();
+
+out:
+	mutex_unlock(&image_data_mutex);
+	return count;
+}
+
+/*
+ * Manage flash routine
+ */
+static inline void opal_flash_manage(uint8_t op)
+{
+	struct manage_flash_t *const args_buf = &manage_flash_data;
+
+	args_buf->status = opal_manage_flash(op);
+}
+
+/*
+ * Show manage flash status
+ */
+static ssize_t manage_show(struct kobject *kobj,
+			   struct kobj_attribute *attr, char *buf)
+{
+	struct manage_flash_t *const args_buf = &manage_flash_data;
+	int rc;
+
+	rc = sprintf(buf, "%d\n", args_buf->status);
+	/* Set status to default*/
+	args_buf->status = FLASH_NO_OP;
+	return rc;
+}
+
+/*
+ * Manage operations:
+ *   0 - Reject
+ *   1 - Commit
+ */
+static ssize_t manage_store(struct kobject *kobj,
+			    struct kobj_attribute *attr,
+			    const char *buf, size_t count)
+{
+	uint8_t op;
+	switch (buf[0]) {
+	case '0':
+		op = FLASH_REJECT_TMP_SIDE;
+		break;
+	case '1':
+		op = FLASH_COMMIT_TMP_SIDE;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* commit/reject temporary image */
+	opal_flash_manage(op);
+	return count;
+}
+
+/*
+ * OPAL update flash
+ */
+static int opal_flash_update(int op)
+{
+	struct opal_sg_list *list;
+	unsigned long addr;
+	int64_t rc = OPAL_PARAMETER;
+
+	if (op == FLASH_UPDATE_CANCEL) {
+		pr_alert("FLASH: Image update cancelled\n");
+		addr = '\0';
+		goto flash;
+	}
+
+	list = opal_vmalloc_to_sg_list(image_data.data, image_data.size);
+	if (!list)
+		goto invalid_img;
+
+	/* First entry address */
+	addr = __pa(list);
+
+flash:
+	rc = opal_update_flash(addr);
+
+invalid_img:
+	return rc;
+}
+
+/* This gets called just before system reboots */
+void opal_flash_update_print_message(void)
+{
+	if (update_flash_data.status != FLASH_IMG_READY)
+		return;
+
+	pr_alert("FLASH: Flashing new firmware\n");
+	pr_alert("FLASH: Image is %u bytes\n", image_data.size);
+	pr_alert("FLASH: Performing flash and reboot/shutdown\n");
+	pr_alert("FLASH: This will take several minutes. Do not power off!\n");
+
+	/* Small delay to help getting the above message out */
+	msleep(500);
+}
+
+/*
+ * Show candidate image status
+ */
+static ssize_t update_show(struct kobject *kobj,
+			   struct kobj_attribute *attr, char *buf)
+{
+	struct update_flash_t *const args_buf = &update_flash_data;
+	return sprintf(buf, "%d\n", args_buf->status);
+}
+
+/*
+ * Set update image flag
+ *  1 - Flash new image
+ *  0 - Cancel flash request
+ */
+static ssize_t update_store(struct kobject *kobj,
+			    struct kobj_attribute *attr,
+			    const char *buf, size_t count)
+{
+	struct update_flash_t *const args_buf = &update_flash_data;
+	int rc = count;
+
+	mutex_lock(&image_data_mutex);
+
+	switch (buf[0]) {
+	case '0':
+		if (args_buf->status == FLASH_IMG_READY)
+			opal_flash_update(FLASH_UPDATE_CANCEL);
+		args_buf->status = FLASH_NO_OP;
+		break;
+	case '1':
+		/* Image is loaded? */
+		if (image_data.status == IMAGE_READY)
+			args_buf->status =
+				opal_flash_update(FLASH_UPDATE_INIT);
+		else
+			args_buf->status = FLASH_INVALID_IMG;
+		break;
+	default:
+		rc = -EINVAL;
+	}
+
+	mutex_unlock(&image_data_mutex);
+	return rc;
+}
+
+/*
+ * Free image buffer
+ */
+static void free_image_buf(void)
+{
+	void *addr;
+	int size;
+
+	addr = image_data.data;
+	size = PAGE_ALIGN(image_data.size);
+	while (size > 0) {
+		ClearPageReserved(vmalloc_to_page(addr));
+		addr += PAGE_SIZE;
+		size -= PAGE_SIZE;
+	}
+	vfree(image_data.data);
+	image_data.data = NULL;
+	image_data.status = IMAGE_INVALID;
+}
+
+/*
+ * Allocate image buffer.
+ */
+static int alloc_image_buf(char *buffer, size_t count)
+{
+	void *addr;
+	int size;
+
+	if (count < sizeof(image_header)) {
+		pr_warn("FLASH: Invalid candidate image\n");
+		return -EINVAL;
+	}
+
+	memcpy(&image_header, (void *)buffer, sizeof(image_header));
+	image_data.size = be32_to_cpu(image_header.size);
+	pr_debug("FLASH: Candidate image size = %u\n", image_data.size);
+
+	if (image_data.size > MAX_IMAGE_SIZE) {
+		pr_warn("FLASH: Too large image\n");
+		return -EINVAL;
+	}
+	if (image_data.size < VALIDATE_BUF_SIZE) {
+		pr_warn("FLASH: Image is shorter than expected\n");
+		return -EINVAL;
+	}
+
+	image_data.data = vzalloc(PAGE_ALIGN(image_data.size));
+	if (!image_data.data) {
+		pr_err("%s : Failed to allocate memory\n", __func__);
+		return -ENOMEM;
+	}
+
+	/* Pin memory */
+	addr = image_data.data;
+	size = PAGE_ALIGN(image_data.size);
+	while (size > 0) {
+		SetPageReserved(vmalloc_to_page(addr));
+		addr += PAGE_SIZE;
+		size -= PAGE_SIZE;
+	}
+
+	image_data.status = IMAGE_LOADING;
+	return 0;
+}
+
+/*
+ * Copy candidate image
+ *
+ * Parse candidate image header to get total image size
+ * and pre-allocate required memory.
+ */
+static ssize_t image_data_write(struct file *filp, struct kobject *kobj,
+				struct bin_attribute *bin_attr,
+				char *buffer, loff_t pos, size_t count)
+{
+	int rc;
+
+	mutex_lock(&image_data_mutex);
+
+	/* New image ? */
+	if (pos == 0) {
+		/* Free memory, if already allocated */
+		if (image_data.data)
+			free_image_buf();
+
+		/* Cancel outstanding image update request */
+		if (update_flash_data.status == FLASH_IMG_READY)
+			opal_flash_update(FLASH_UPDATE_CANCEL);
+
+		/* Allocate memory */
+		rc = alloc_image_buf(buffer, count);
+		if (rc)
+			goto out;
+	}
+
+	if (image_data.status != IMAGE_LOADING) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	if ((pos + count) > image_data.size) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	memcpy(image_data.data + pos, (void *)buffer, count);
+	rc = count;
+
+	/* Set image status */
+	if ((pos + count) == image_data.size) {
+		pr_debug("FLASH: Candidate image loaded....\n");
+		image_data.status = IMAGE_READY;
+	}
+
+out:
+	mutex_unlock(&image_data_mutex);
+	return rc;
+}
+
+/*
+ * sysfs interface :
+ *  OPAL uses below sysfs files for code update.
+ *  We create these files under /sys/firmware/opal.
+ *
+ *   image		: Interface to load candidate firmware image
+ *   validate_flash	: Validate firmware image
+ *   manage_flash	: Commit/Reject firmware image
+ *   update_flash	: Flash new firmware image
+ *
+ */
+static const struct bin_attribute image_data_attr = {
+	.attr = {.name = "image", .mode = 0200},
+	.size = MAX_IMAGE_SIZE,	/* Limit image size */
+	.write = image_data_write,
+};
+
+static struct kobj_attribute validate_attribute =
+	__ATTR(validate_flash, 0600, validate_show, validate_store);
+
+static struct kobj_attribute manage_attribute =
+	__ATTR(manage_flash, 0600, manage_show, manage_store);
+
+static struct kobj_attribute update_attribute =
+	__ATTR(update_flash, 0600, update_show, update_store);
+
+static struct attribute *image_op_attrs[] = {
+	&validate_attribute.attr,
+	&manage_attribute.attr,
+	&update_attribute.attr,
+	NULL	/* need to NULL terminate the list of attributes */
+};
+
+static const struct attribute_group image_op_attr_group = {
+	.attrs = image_op_attrs,
+};
+
+void __init opal_flash_update_init(void)
+{
+	int ret;
+
+	/* Firmware update is not supported by firmware */
+	if (!opal_check_token(OPAL_FLASH_VALIDATE))
+		return;
+
+	/* Allocate validate image buffer */
+	validate_flash_data.buf = kzalloc(VALIDATE_BUF_SIZE, GFP_KERNEL);
+	if (!validate_flash_data.buf) {
+		pr_err("%s : Failed to allocate memory\n", __func__);
+		return;
+	}
+
+	/* Make sure /sys/firmware/opal directory is created */
+	if (!opal_kobj) {
+		pr_warn("FLASH: opal kobject is not available\n");
+		goto nokobj;
+	}
+
+	/* Create the sysfs files */
+	ret = sysfs_create_group(opal_kobj, &image_op_attr_group);
+	if (ret) {
+		pr_warn("FLASH: Failed to create sysfs files\n");
+		goto nokobj;
+	}
+
+	ret = sysfs_create_bin_file(opal_kobj, &image_data_attr);
+	if (ret) {
+		pr_warn("FLASH: Failed to create sysfs files\n");
+		goto nosysfs_file;
+	}
+
+	/* Set default status */
+	validate_flash_data.status = FLASH_NO_OP;
+	manage_flash_data.status = FLASH_NO_OP;
+	update_flash_data.status = FLASH_NO_OP;
+	image_data.status = IMAGE_INVALID;
+	return;
+
+nosysfs_file:
+	sysfs_remove_group(opal_kobj, &image_op_attr_group);
+
+nokobj:
+	kfree(validate_flash_data.buf);
+	return;
+}