Merge tag 'net-next-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Paolo Abeni:
 "The most significant set of changes is the per netns RTNL. The new
  behavior is disabled by default, regression risk should be contained.

  Notably the new config knob PTP_1588_CLOCK_VMCLOCK will inherit its
  default value from PTP_1588_CLOCK_KVM, as the first is intended to be
  a more reliable replacement for the latter.

  Core:

   - Started a very large, in-progress, effort to make the RTNL lock
     scope per network-namespace, thus reducing the lock contention
     significantly in the containerized use-case, comprising:
       - RCU-ified some relevant slices of the FIB control path
       - introduce basic per netns locking helpers
       - namespacified the IPv4 address hash table
       - remove rtnl_register{,_module}() in favour of
         rtnl_register_many()
       - refactor rtnl_{new,del,set}link() moving as much validation as
         possible out of RTNL lock
       - convert all phonet doit() and dumpit() handlers to RCU
       - convert IPv4 addresses manipulation to per-netns RTNL
       - convert virtual interface creation to per-netns RTNL
     the per-netns lock infrastructure is guarded by the
     CONFIG_DEBUG_NET_SMALL_RTNL knob, disabled by default ad interim.

   - Introduce NAPI suspension, to efficiently switching between busy
     polling (NAPI processing suspended) and normal processing.

   - Migrate the IPv4 routing input, output and control path from direct
     ToS usage to DSCP macros. This is a work in progress to make ECN
     handling consistent and reliable.

   - Add drop reasons support to the IPv4 rotue input path, allowing
     better introspection in case of packets drop.

   - Make FIB seqnum lockless, dropping RTNL protection for read access.

   - Make inet{,v6} addresses hashing less predicable.

   - Allow providing timestamp OPT_ID via cmsg, to correlate TX packets
     and timestamps

  Things we sprinkled into general kernel code:

   - Add small file operations for debugfs, to reduce the struct ops
     size.

   - Refactoring and optimization for the implementation of page_frag
     API, This is a preparatory work to consolidate the page_frag
     implementation.

  Netfilter:

   - Optimize set element transactions to reduce memory consumption

   - Extended netlink error reporting for attribute parser failure.

   - Make legacy xtables configs user selectable, giving users the
     option to configure iptables without enabling any other config.

   - Address a lot of false-positive RCU issues, pointed by recent CI
     improvements.

  BPF:

   - Put xsk sockets on a struct diet and add various cleanups. Overall,
     this helps to bump performance by 12% for some workloads.

   - Extend BPF selftests to increase coverage of XDP features in
     combination with BPF cpumap.

   - Optimize and homogenize bpf_csum_diff helper for all archs and also
     add a batch of new BPF selftests for it.

   - Extend netkit with an option to delegate skb->{mark,priority}
     scrubbing to its BPF program.

   - Make the bpf_get_netns_cookie() helper available also to tc(x) BPF
     programs.

  Protocols:

   - Introduces 4-tuple hash for connected udp sockets, speeding-up
     significantly connected sockets lookup.

   - Add a fastpath for some TCP timers that usually expires after
     close, the socket lock contention.

   - Add inbound and outbound xfrm state caches to speed up state
     lookups.

   - Avoid sending MPTCP advertisements on stale subflows, reducing
     risks on loosing them.

   - Make neighbours table flushing more scalable, maintaining per
     device neigh lists.

  Driver API:

   - Introduce a unified interface to configure transmission H/W
     shaping, and expose it to user-space via generic-netlink.

   - Add support for per-NAPI config via netlink. This makes napi
     configuration persistent across queues removal and re-creation.
     Requires driver updates, currently supported drivers are:
     nVidia/Mellanox mlx4 and mlx5, Broadcom brcm and Intel ice.

   - Add ethtool support for writing SFP / PHY firmware blocks.

   - Track RSS context allocation from ethtool core.

   - Implement support for mirroring to DSA CPU port, via TC mirror
     offload.

   - Consolidate FDB updates notification, to avoid duplicates on
     device-specific entries.

   - Expose DPLL clock quality level to the user-space.

   - Support master-slave PHY config via device tree.

  Tests and tooling:

   - forwarding: introduce deferred commands, to simplify the cleanup
     phase

  Drivers:

   - Updated several drivers - Amazon vNic, Google vNic, Microsoft vNic,
     Intel e1000e and Broadcom Tigon3 - to use netdev-genl to link the
     IRQs and queues to NAPI IDs, allowing busy polling and better
     introspection.

   - Ethernet high-speed NICs:
      - nVidia/Mellanox:
         - mlx5:
           - a large refactor to implement support for cross E-Switch
             scheduling
           - refactor H/W conter management to let it scale better
           - H/W GRO cleanups
      - Intel (100G, ice)::
         - add support for ethtool reset
         - implement support for per TX queue H/W shaping
      - AMD/Solarflare:
         - implement per device queue stats support
      - Broadcom (bnxt):
         - improve wildcard l4proto on IPv4/IPv6 ntuple rules
      - Marvell Octeon:
         - Add representor support for each Resource Virtualization Unit
           (RVU) device.
      - Hisilicon:
         - add support for the BMC Gigabit Ethernet
      - IBM (EMAC):
         - driver cleanup and modernization
      - Cisco (VIC):
         - raise the queues number limit to 256

   - Ethernet virtual:
      - Google vNIC:
         - implement page pool support
      - macsec:
         - inherit lower device's features and TSO limits when
           offloading
      - virtio_net:
         - enable premapped mode by default
         - support for XDP socket(AF_XDP) zerocopy TX
      - wireguard:
         - set the TSO max size to be GSO_MAX_SIZE, to aggregate larger
           packets.

   - Ethernet NICs embedded and virtual:
      - Broadcom ASP:
         - enable software timestamping
      - Freescale:
         - add enetc4 PF driver
      - MediaTek: Airoha SoC:
         - implement BQL support
      - RealTek r8169:
         - enable TSO by default on r8168/r8125
         - implement extended ethtool stats
      - Renesas AVB:
         - enable TX checksum offload
      - Synopsys (stmmac):
         - support header splitting for vlan tagged packets
         - move common code for DWMAC4 and DWXGMAC into a separate FPE
           module.
         - add dwmac driver support for T-HEAD TH1520 SoC
      - Synopsys (xpcs):
         - driver refactor and cleanup
      - TI:
         - icssg_prueth: add VLAN offload support
      - Xilinx emaclite:
         - add clock support

   - Ethernet switches:
      - Microchip:
         - implement support for the lan969x Ethernet switch family
         - add LAN9646 switch support to KSZ DSA driver

   - Ethernet PHYs:
      - Marvel: 88q2x: enable auto negotiation
      - Microchip: add support for LAN865X Rev B1 and LAN867X Rev C1/C2

   - PTP:
      - Add support for the Amazon virtual clock device
      - Add PtP driver for s390 clocks

   - WiFi:
      - mac80211
         - EHT 1024 aggregation size for transmissions
         - new operation to indicate that a new interface is to be added
         - support radio separation of multi-band devices
         - move wireless extension spy implementation to libiw
      - Broadcom:
         - brcmfmac: optional LPO clock support
      - Microchip:
         - add support for Atmel WILC3000
      - Qualcomm (ath12k):
         - firmware coredump collection support
         - add debugfs support for a multitude of statistics
      - Qualcomm (ath5k):
         -  Arcadyan ARV45XX AR2417 & Gigaset SX76[23] AR241[34]A support
      - Realtek:
         - rtw88: 8821au and 8812au USB adapters support
         - rtw89: add thermal protection
         - rtw89: fine tune BT-coexsitence to improve user experience
         - rtw89: firmware secure boot for WiFi 6 chip

   - Bluetooth
      - add Qualcomm WCN785x support for ids Foxconn 0xe0fc/0xe0f3 and
        0x13d3:0x3623
      - add Realtek RTL8852BE support for id Foxconn 0xe123
      - add MediaTek MT7920 support for wireless module ids
      - btintel_pcie: add handshake between driver and firmware
      - btintel_pcie: add recovery mechanism
      - btnxpuart: add GPIO support to power save feature"

* tag 'net-next-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1475 commits)
  mm: page_frag: fix a compile error when kernel is not compiled
  Documentation: tipc: fix formatting issue in tipc.rst
  selftests: nic_performance: Add selftest for performance of NIC driver
  selftests: nic_link_layer: Add selftest case for speed and duplex states
  selftests: nic_link_layer: Add link layer selftest for NIC driver
  bnxt_en: Add FW trace coredump segments to the coredump
  bnxt_en: Add a new ethtool -W dump flag
  bnxt_en: Add 2 parameters to bnxt_fill_coredump_seg_hdr()
  bnxt_en: Add functions to copy host context memory
  bnxt_en: Do not free FW log context memory
  bnxt_en: Manage the FW trace context memory
  bnxt_en: Allocate backing store memory for FW trace logs
  bnxt_en: Add a 'force' parameter to bnxt_free_ctx_mem()
  bnxt_en: Refactor bnxt_free_ctx_mem()
  bnxt_en: Add mem_valid bit to struct bnxt_ctx_mem_type
  bnxt_en: Update firmware interface spec to 1.10.3.85
  selftests/bpf: Add some tests with sockmap SK_PASS
  bpf: fix recursive lock when verdict program return SK_PASS
  wireguard: device: support big tcp GSO
  wireguard: selftests: load nf_conntrack if not present
  ...

1 files changed, 219 insertions, 103 deletions

diff --git a/lib/packing.c b/lib/packing.c
index 3f656167c17e0..793942745e34f 100644
--- a/lib/packing.c
+++ b/lib/packing.c
@@ -9,52 +9,53 @@
 #include <linux/types.h>
 #include <linux/bitrev.h>
 
-static int get_le_offset(int offset)
+/**
+ * calculate_box_addr - Determine physical location of byte in buffer
+ * @box: Index of byte within buffer seen as a logical big-endian big number
+ * @len: Size of buffer in bytes
+ * @quirks: mask of QUIRK_LSW32_IS_FIRST and QUIRK_LITTLE_ENDIAN
+ *
+ * Function interprets the buffer as a @len byte sized big number, and returns
+ * the physical offset of the @box logical octet within it. Internally, it
+ * treats the big number as groups of 4 bytes. If @len is not a multiple of 4,
+ * the last group may be shorter.
+ *
+ * @QUIRK_LSW32_IS_FIRST gives the ordering of groups of 4 octets relative to
+ * each other. If set, the most significant group of 4 octets is last in the
+ * buffer (and may be truncated if @len is not a multiple of 4).
+ *
+ * @QUIRK_LITTLE_ENDIAN gives the ordering of bytes within each group of 4.
+ * If set, the most significant byte is last in the group. If @len takes the
+ * form of 4k+3, the last group will only be able to represent 24 bits, and its
+ * most significant octet is byte 2.
+ *
+ * Return: the physical offset into the buffer corresponding to the logical box.
+ */
+static size_t calculate_box_addr(size_t box, size_t len, u8 quirks)
 {
-	int closest_multiple_of_4;
+	size_t offset_of_group, offset_in_group, this_group = box / 4;
+	size_t group_size;
 
-	closest_multiple_of_4 = (offset / 4) * 4;
-	offset -= closest_multiple_of_4;
-	return closest_multiple_of_4 + (3 - offset);
-}
+	if (quirks & QUIRK_LSW32_IS_FIRST)
+		offset_of_group = this_group * 4;
+	else
+		offset_of_group = len - ((this_group + 1) * 4);
 
-static int get_reverse_lsw32_offset(int offset, size_t len)
-{
-	int closest_multiple_of_4;
-	int word_index;
-
-	word_index = offset / 4;
-	closest_multiple_of_4 = word_index * 4;
-	offset -= closest_multiple_of_4;
-	word_index = (len / 4) - word_index - 1;
-	return word_index * 4 + offset;
-}
+	group_size = min(4, len - offset_of_group);
 
-static void adjust_for_msb_right_quirk(u64 *to_write, int *box_start_bit,
-				       int *box_end_bit, u8 *box_mask)
-{
-	int box_bit_width = *box_start_bit - *box_end_bit + 1;
-	int new_box_start_bit, new_box_end_bit;
-
-	*to_write >>= *box_end_bit;
-	*to_write = bitrev8(*to_write) >> (8 - box_bit_width);
-	*to_write <<= *box_end_bit;
-
-	new_box_end_bit   = box_bit_width - *box_start_bit - 1;
-	new_box_start_bit = box_bit_width - *box_end_bit - 1;
-	*box_mask = GENMASK_ULL(new_box_start_bit, new_box_end_bit);
-	*box_start_bit = new_box_start_bit;
-	*box_end_bit   = new_box_end_bit;
+	if (quirks & QUIRK_LITTLE_ENDIAN)
+		offset_in_group = box - this_group * 4;
+	else
+		offset_in_group = group_size - (box - this_group * 4) - 1;
+
+	return offset_of_group + offset_in_group;
 }
 
 /**
- * packing - Convert numbers (currently u64) between a packed and an unpacked
- *	     format. Unpacked means laid out in memory in the CPU's native
- *	     understanding of integers, while packed means anything else that
- *	     requires translation.
+ * pack - Pack u64 number into bitfield of buffer.
  *
  * @pbuf: Pointer to a buffer holding the packed value.
- * @uval: Pointer to an u64 holding the unpacked value.
+ * @uval: CPU-readable unpacked value to pack.
  * @startbit: The index (in logical notation, compensated for quirks) where
  *	      the packed value starts within pbuf. Must be larger than, or
  *	      equal to, endbit.
@@ -62,79 +63,179 @@ static void adjust_for_msb_right_quirk(u64 *to_write, int *box_start_bit,
  *	    the packed value ends within pbuf. Must be smaller than, or equal
  *	    to, startbit.
  * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf.
- * @op: If PACK, then uval will be treated as const pointer and copied (packed)
- *	into pbuf, between startbit and endbit.
- *	If UNPACK, then pbuf will be treated as const pointer and the logical
- *	value between startbit and endbit will be copied (unpacked) to uval.
  * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and
  *	    QUIRK_MSB_ON_THE_RIGHT.
  *
  * Return: 0 on success, EINVAL or ERANGE if called incorrectly. Assuming
- *	   correct usage, return code may be discarded.
- *	   If op is PACK, pbuf is modified.
- *	   If op is UNPACK, uval is modified.
+ *	   correct usage, return code may be discarded. The @pbuf memory will
+ *	   be modified on success.
  */
-int packing(void *pbuf, u64 *uval, int startbit, int endbit, size_t pbuflen,
-	    enum packing_op op, u8 quirks)
+int pack(void *pbuf, u64 uval, size_t startbit, size_t endbit, size_t pbuflen,
+	 u8 quirks)
 {
-	/* Number of bits for storing "uval"
-	 * also width of the field to access in the pbuf
-	 */
-	u64 value_width;
 	/* Logical byte indices corresponding to the
 	 * start and end of the field.
 	 */
 	int plogical_first_u8, plogical_last_u8, box;
+	/* width of the field to access in the pbuf */
+	u64 value_width;
 
-	/* startbit is expected to be larger than endbit */
-	if (startbit < endbit)
+	/* startbit is expected to be larger than endbit, and both are
+	 * expected to be within the logically addressable range of the buffer.
+	 */
+	if (unlikely(startbit < endbit || startbit >= BITS_PER_BYTE * pbuflen))
 		/* Invalid function call */
 		return -EINVAL;
 
 	value_width = startbit - endbit + 1;
-	if (value_width > 64)
+	if (unlikely(value_width > 64))
 		return -ERANGE;
 
 	/* Check if "uval" fits in "value_width" bits.
 	 * If value_width is 64, the check will fail, but any
 	 * 64-bit uval will surely fit.
 	 */
-	if (op == PACK && value_width < 64 && (*uval >= (1ull << value_width)))
+	if (unlikely(value_width < 64 && uval >= (1ull << value_width)))
 		/* Cannot store "uval" inside "value_width" bits.
 		 * Truncating "uval" is most certainly not desirable,
 		 * so simply erroring out is appropriate.
 		 */
 		return -ERANGE;
 
+	/* Iterate through an idealistic view of the pbuf as an u64 with
+	 * no quirks, u8 by u8 (aligned at u8 boundaries), from high to low
+	 * logical bit significance. "box" denotes the current logical u8.
+	 */
+	plogical_first_u8 = startbit / BITS_PER_BYTE;
+	plogical_last_u8  = endbit / BITS_PER_BYTE;
+
+	for (box = plogical_first_u8; box >= plogical_last_u8; box--) {
+		/* Bit indices into the currently accessed 8-bit box */
+		size_t box_start_bit, box_end_bit, box_addr;
+		u8  box_mask;
+		/* Corresponding bits from the unpacked u64 parameter */
+		size_t proj_start_bit, proj_end_bit;
+		u64 proj_mask;
+		u64 pval;
+
+		/* This u8 may need to be accessed in its entirety
+		 * (from bit 7 to bit 0), or not, depending on the
+		 * input arguments startbit and endbit.
+		 */
+		if (box == plogical_first_u8)
+			box_start_bit = startbit % BITS_PER_BYTE;
+		else
+			box_start_bit = 7;
+		if (box == plogical_last_u8)
+			box_end_bit = endbit % BITS_PER_BYTE;
+		else
+			box_end_bit = 0;
+
+		/* We have determined the box bit start and end.
+		 * Now we calculate where this (masked) u8 box would fit
+		 * in the unpacked (CPU-readable) u64 - the u8 box's
+		 * projection onto the unpacked u64. Though the
+		 * box is u8, the projection is u64 because it may fall
+		 * anywhere within the unpacked u64.
+		 */
+		proj_start_bit = ((box * BITS_PER_BYTE) + box_start_bit) - endbit;
+		proj_end_bit = ((box * BITS_PER_BYTE) + box_end_bit) - endbit;
+		proj_mask = GENMASK_ULL(proj_start_bit, proj_end_bit);
+		box_mask = GENMASK(box_start_bit, box_end_bit);
+
+		/* Determine the offset of the u8 box inside the pbuf,
+		 * adjusted for quirks. The adjusted box_addr will be used for
+		 * effective addressing inside the pbuf (so it's not
+		 * logical any longer).
+		 */
+		box_addr = calculate_box_addr(box, pbuflen, quirks);
+
+		/* Write to pbuf, read from uval */
+		pval = uval & proj_mask;
+		pval >>= proj_end_bit;
+		pval <<= box_end_bit;
+
+		if (quirks & QUIRK_MSB_ON_THE_RIGHT) {
+			pval = bitrev8(pval);
+			box_mask = bitrev8(box_mask);
+		}
+
+		((u8 *)pbuf)[box_addr] &= ~box_mask;
+		((u8 *)pbuf)[box_addr] |= pval;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(pack);
+
+/**
+ * unpack - Unpack u64 number from packed buffer.
+ *
+ * @pbuf: Pointer to a buffer holding the packed value.
+ * @uval: Pointer to an u64 holding the unpacked value.
+ * @startbit: The index (in logical notation, compensated for quirks) where
+ *	      the packed value starts within pbuf. Must be larger than, or
+ *	      equal to, endbit.
+ * @endbit: The index (in logical notation, compensated for quirks) where
+ *	    the packed value ends within pbuf. Must be smaller than, or equal
+ *	    to, startbit.
+ * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf.
+ * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and
+ *	    QUIRK_MSB_ON_THE_RIGHT.
+ *
+ * Return: 0 on success, EINVAL or ERANGE if called incorrectly. Assuming
+ *	   correct usage, return code may be discarded. The @uval will be
+ *	   modified on success.
+ */
+int unpack(const void *pbuf, u64 *uval, size_t startbit, size_t endbit,
+	   size_t pbuflen, u8 quirks)
+{
+	/* Logical byte indices corresponding to the
+	 * start and end of the field.
+	 */
+	int plogical_first_u8, plogical_last_u8, box;
+	/* width of the field to access in the pbuf */
+	u64 value_width;
+
+	/* startbit is expected to be larger than endbit, and both are
+	 * expected to be within the logically addressable range of the buffer.
+	 */
+	if (unlikely(startbit < endbit || startbit >= BITS_PER_BYTE * pbuflen))
+		/* Invalid function call */
+		return -EINVAL;
+
+	value_width = startbit - endbit + 1;
+	if (unlikely(value_width > 64))
+		return -ERANGE;
+
 	/* Initialize parameter */
-	if (op == UNPACK)
-		*uval = 0;
+	*uval = 0;
 
 	/* Iterate through an idealistic view of the pbuf as an u64 with
 	 * no quirks, u8 by u8 (aligned at u8 boundaries), from high to low
 	 * logical bit significance. "box" denotes the current logical u8.
 	 */
-	plogical_first_u8 = startbit / 8;
-	plogical_last_u8  = endbit / 8;
+	plogical_first_u8 = startbit / BITS_PER_BYTE;
+	plogical_last_u8  = endbit / BITS_PER_BYTE;
 
 	for (box = plogical_first_u8; box >= plogical_last_u8; box--) {
 		/* Bit indices into the currently accessed 8-bit box */
-		int box_start_bit, box_end_bit, box_addr;
+		size_t box_start_bit, box_end_bit, box_addr;
 		u8  box_mask;
 		/* Corresponding bits from the unpacked u64 parameter */
-		int proj_start_bit, proj_end_bit;
+		size_t proj_start_bit, proj_end_bit;
 		u64 proj_mask;
+		u64 pval;
 
 		/* This u8 may need to be accessed in its entirety
 		 * (from bit 7 to bit 0), or not, depending on the
 		 * input arguments startbit and endbit.
 		 */
 		if (box == plogical_first_u8)
-			box_start_bit = startbit % 8;
+			box_start_bit = startbit % BITS_PER_BYTE;
 		else
 			box_start_bit = 7;
 		if (box == plogical_last_u8)
-			box_end_bit = endbit % 8;
+			box_end_bit = endbit % BITS_PER_BYTE;
 		else
 			box_end_bit = 0;
 
@@ -145,57 +246,72 @@ int packing(void *pbuf, u64 *uval, int startbit, int endbit, size_t pbuflen,
 		 * box is u8, the projection is u64 because it may fall
 		 * anywhere within the unpacked u64.
 		 */
-		proj_start_bit = ((box * 8) + box_start_bit) - endbit;
-		proj_end_bit   = ((box * 8) + box_end_bit) - endbit;
+		proj_start_bit = ((box * BITS_PER_BYTE) + box_start_bit) - endbit;
+		proj_end_bit = ((box * BITS_PER_BYTE) + box_end_bit) - endbit;
 		proj_mask = GENMASK_ULL(proj_start_bit, proj_end_bit);
-		box_mask  = GENMASK_ULL(box_start_bit, box_end_bit);
+		box_mask = GENMASK(box_start_bit, box_end_bit);
 
 		/* Determine the offset of the u8 box inside the pbuf,
 		 * adjusted for quirks. The adjusted box_addr will be used for
 		 * effective addressing inside the pbuf (so it's not
 		 * logical any longer).
 		 */
-		box_addr = pbuflen - box - 1;
-		if (quirks & QUIRK_LITTLE_ENDIAN)
-			box_addr = get_le_offset(box_addr);
-		if (quirks & QUIRK_LSW32_IS_FIRST)
-			box_addr = get_reverse_lsw32_offset(box_addr,
-							    pbuflen);
-
-		if (op == UNPACK) {
-			u64 pval;
-
-			/* Read from pbuf, write to uval */
-			pval = ((u8 *)pbuf)[box_addr] & box_mask;
-			if (quirks & QUIRK_MSB_ON_THE_RIGHT)
-				adjust_for_msb_right_quirk(&pval,
-							   &box_start_bit,
-							   &box_end_bit,
-							   &box_mask);
-
-			pval >>= box_end_bit;
-			pval <<= proj_end_bit;
-			*uval &= ~proj_mask;
-			*uval |= pval;
-		} else {
-			u64 pval;
-
-			/* Write to pbuf, read from uval */
-			pval = (*uval) & proj_mask;
-			pval >>= proj_end_bit;
-			if (quirks & QUIRK_MSB_ON_THE_RIGHT)
-				adjust_for_msb_right_quirk(&pval,
-							   &box_start_bit,
-							   &box_end_bit,
-							   &box_mask);
-
-			pval <<= box_end_bit;
-			((u8 *)pbuf)[box_addr] &= ~box_mask;
-			((u8 *)pbuf)[box_addr] |= pval;
-		}
+		box_addr = calculate_box_addr(box, pbuflen, quirks);
+
+		/* Read from pbuf, write to uval */
+		pval = ((u8 *)pbuf)[box_addr];
+
+		if (quirks & QUIRK_MSB_ON_THE_RIGHT)
+			pval = bitrev8(pval);
+
+		pval &= box_mask;
+
+		pval >>= box_end_bit;
+		pval <<= proj_end_bit;
+		*uval &= ~proj_mask;
+		*uval |= pval;
 	}
 	return 0;
 }
+EXPORT_SYMBOL(unpack);
+
+/**
+ * packing - Convert numbers (currently u64) between a packed and an unpacked
+ *	     format. Unpacked means laid out in memory in the CPU's native
+ *	     understanding of integers, while packed means anything else that
+ *	     requires translation.
+ *
+ * @pbuf: Pointer to a buffer holding the packed value.
+ * @uval: Pointer to an u64 holding the unpacked value.
+ * @startbit: The index (in logical notation, compensated for quirks) where
+ *	      the packed value starts within pbuf. Must be larger than, or
+ *	      equal to, endbit.
+ * @endbit: The index (in logical notation, compensated for quirks) where
+ *	    the packed value ends within pbuf. Must be smaller than, or equal
+ *	    to, startbit.
+ * @pbuflen: The length in bytes of the packed buffer pointed to by @pbuf.
+ * @op: If PACK, then uval will be treated as const pointer and copied (packed)
+ *	into pbuf, between startbit and endbit.
+ *	If UNPACK, then pbuf will be treated as const pointer and the logical
+ *	value between startbit and endbit will be copied (unpacked) to uval.
+ * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and
+ *	    QUIRK_MSB_ON_THE_RIGHT.
+ *
+ * Note: this is deprecated, prefer to use pack() or unpack() in new code.
+ *
+ * Return: 0 on success, EINVAL or ERANGE if called incorrectly. Assuming
+ *	   correct usage, return code may be discarded.
+ *	   If op is PACK, pbuf is modified.
+ *	   If op is UNPACK, uval is modified.
+ */
+int packing(void *pbuf, u64 *uval, int startbit, int endbit, size_t pbuflen,
+	    enum packing_op op, u8 quirks)
+{
+	if (op == PACK)
+		return pack(pbuf, *uval, startbit, endbit, pbuflen, quirks);
+
+	return unpack(pbuf, uval, startbit, endbit, pbuflen, quirks);
+}
 EXPORT_SYMBOL(packing);
 
 MODULE_DESCRIPTION("Generic bitfield packing and unpacking");