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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/powerpc/lib/copy_32.S
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
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(). ...
Diffstat (limited to 'arch/powerpc/lib/copy_32.S')
-rw-r--r--arch/powerpc/lib/copy_32.S515
1 files changed, 515 insertions, 0 deletions
diff --git a/arch/powerpc/lib/copy_32.S b/arch/powerpc/lib/copy_32.S
new file mode 100644
index 000000000..3e9c27c46
--- /dev/null
+++ b/arch/powerpc/lib/copy_32.S
@@ -0,0 +1,515 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Memory copy functions for 32-bit PowerPC.
+ *
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ */
+#include <asm/processor.h>
+#include <asm/cache.h>
+#include <asm/errno.h>
+#include <asm/ppc_asm.h>
+#include <asm/export.h>
+#include <asm/code-patching-asm.h>
+#include <asm/kasan.h>
+
+#define COPY_16_BYTES \
+ lwz r7,4(r4); \
+ lwz r8,8(r4); \
+ lwz r9,12(r4); \
+ lwzu r10,16(r4); \
+ stw r7,4(r6); \
+ stw r8,8(r6); \
+ stw r9,12(r6); \
+ stwu r10,16(r6)
+
+#define COPY_16_BYTES_WITHEX(n) \
+8 ## n ## 0: \
+ lwz r7,4(r4); \
+8 ## n ## 1: \
+ lwz r8,8(r4); \
+8 ## n ## 2: \
+ lwz r9,12(r4); \
+8 ## n ## 3: \
+ lwzu r10,16(r4); \
+8 ## n ## 4: \
+ stw r7,4(r6); \
+8 ## n ## 5: \
+ stw r8,8(r6); \
+8 ## n ## 6: \
+ stw r9,12(r6); \
+8 ## n ## 7: \
+ stwu r10,16(r6)
+
+#define COPY_16_BYTES_EXCODE(n) \
+9 ## n ## 0: \
+ addi r5,r5,-(16 * n); \
+ b 104f; \
+9 ## n ## 1: \
+ addi r5,r5,-(16 * n); \
+ b 105f; \
+ EX_TABLE(8 ## n ## 0b,9 ## n ## 0b); \
+ EX_TABLE(8 ## n ## 1b,9 ## n ## 0b); \
+ EX_TABLE(8 ## n ## 2b,9 ## n ## 0b); \
+ EX_TABLE(8 ## n ## 3b,9 ## n ## 0b); \
+ EX_TABLE(8 ## n ## 4b,9 ## n ## 1b); \
+ EX_TABLE(8 ## n ## 5b,9 ## n ## 1b); \
+ EX_TABLE(8 ## n ## 6b,9 ## n ## 1b); \
+ EX_TABLE(8 ## n ## 7b,9 ## n ## 1b)
+
+ .text
+
+CACHELINE_BYTES = L1_CACHE_BYTES
+LG_CACHELINE_BYTES = L1_CACHE_SHIFT
+CACHELINE_MASK = (L1_CACHE_BYTES-1)
+
+#ifndef CONFIG_KASAN
+_GLOBAL(memset16)
+ rlwinm. r0 ,r5, 31, 1, 31
+ addi r6, r3, -4
+ beq- 2f
+ rlwimi r4 ,r4 ,16 ,0 ,15
+ mtctr r0
+1: stwu r4, 4(r6)
+ bdnz 1b
+2: andi. r0, r5, 1
+ beqlr
+ sth r4, 4(r6)
+ blr
+EXPORT_SYMBOL(memset16)
+#endif
+
+/*
+ * Use dcbz on the complete cache lines in the destination
+ * to set them to zero. This requires that the destination
+ * area is cacheable. -- paulus
+ *
+ * During early init, cache might not be active yet, so dcbz cannot be used.
+ * We therefore skip the optimised bloc that uses dcbz. This jump is
+ * replaced by a nop once cache is active. This is done in machine_init()
+ */
+_GLOBAL_KASAN(memset)
+ cmplwi 0,r5,4
+ blt 7f
+
+ rlwimi r4,r4,8,16,23
+ rlwimi r4,r4,16,0,15
+
+ stw r4,0(r3)
+ beqlr
+ andi. r0,r3,3
+ add r5,r0,r5
+ subf r6,r0,r3
+ cmplwi 0,r4,0
+ /*
+ * Skip optimised bloc until cache is enabled. Will be replaced
+ * by 'bne' during boot to use normal procedure if r4 is not zero
+ */
+5: b 2f
+ patch_site 5b, patch__memset_nocache
+
+ clrlwi r7,r6,32-LG_CACHELINE_BYTES
+ add r8,r7,r5
+ srwi r9,r8,LG_CACHELINE_BYTES
+ addic. r9,r9,-1 /* total number of complete cachelines */
+ ble 2f
+ xori r0,r7,CACHELINE_MASK & ~3
+ srwi. r0,r0,2
+ beq 3f
+ mtctr r0
+4: stwu r4,4(r6)
+ bdnz 4b
+3: mtctr r9
+ li r7,4
+10: dcbz r7,r6
+ addi r6,r6,CACHELINE_BYTES
+ bdnz 10b
+ clrlwi r5,r8,32-LG_CACHELINE_BYTES
+ addi r5,r5,4
+
+2: srwi r0,r5,2
+ mtctr r0
+ bdz 6f
+1: stwu r4,4(r6)
+ bdnz 1b
+6: andi. r5,r5,3
+ beqlr
+ mtctr r5
+ addi r6,r6,3
+8: stbu r4,1(r6)
+ bdnz 8b
+ blr
+
+7: cmpwi 0,r5,0
+ beqlr
+ mtctr r5
+ addi r6,r3,-1
+9: stbu r4,1(r6)
+ bdnz 9b
+ blr
+EXPORT_SYMBOL(memset)
+EXPORT_SYMBOL_KASAN(memset)
+
+/*
+ * This version uses dcbz on the complete cache lines in the
+ * destination area to reduce memory traffic. This requires that
+ * the destination area is cacheable.
+ * We only use this version if the source and dest don't overlap.
+ * -- paulus.
+ *
+ * During early init, cache might not be active yet, so dcbz cannot be used.
+ * We therefore jump to generic_memcpy which doesn't use dcbz. This jump is
+ * replaced by a nop once cache is active. This is done in machine_init()
+ */
+_GLOBAL_KASAN(memmove)
+ cmplw 0,r3,r4
+ bgt backwards_memcpy
+ /* fall through */
+
+_GLOBAL_KASAN(memcpy)
+1: b generic_memcpy
+ patch_site 1b, patch__memcpy_nocache
+
+ add r7,r3,r5 /* test if the src & dst overlap */
+ add r8,r4,r5
+ cmplw 0,r4,r7
+ cmplw 1,r3,r8
+ crand 0,0,4 /* cr0.lt &= cr1.lt */
+ blt generic_memcpy /* if regions overlap */
+
+ addi r4,r4,-4
+ addi r6,r3,-4
+ neg r0,r3
+ andi. r0,r0,CACHELINE_MASK /* # bytes to start of cache line */
+ beq 58f
+
+ cmplw 0,r5,r0 /* is this more than total to do? */
+ blt 63f /* if not much to do */
+ andi. r8,r0,3 /* get it word-aligned first */
+ subf r5,r0,r5
+ mtctr r8
+ beq+ 61f
+70: lbz r9,4(r4) /* do some bytes */
+ addi r4,r4,1
+ addi r6,r6,1
+ stb r9,3(r6)
+ bdnz 70b
+61: srwi. r0,r0,2
+ mtctr r0
+ beq 58f
+72: lwzu r9,4(r4) /* do some words */
+ stwu r9,4(r6)
+ bdnz 72b
+
+58: srwi. r0,r5,LG_CACHELINE_BYTES /* # complete cachelines */
+ clrlwi r5,r5,32-LG_CACHELINE_BYTES
+ li r11,4
+ mtctr r0
+ beq 63f
+53:
+ dcbz r11,r6
+ COPY_16_BYTES
+#if L1_CACHE_BYTES >= 32
+ COPY_16_BYTES
+#if L1_CACHE_BYTES >= 64
+ COPY_16_BYTES
+ COPY_16_BYTES
+#if L1_CACHE_BYTES >= 128
+ COPY_16_BYTES
+ COPY_16_BYTES
+ COPY_16_BYTES
+ COPY_16_BYTES
+#endif
+#endif
+#endif
+ bdnz 53b
+
+63: srwi. r0,r5,2
+ mtctr r0
+ beq 64f
+30: lwzu r0,4(r4)
+ stwu r0,4(r6)
+ bdnz 30b
+
+64: andi. r0,r5,3
+ mtctr r0
+ beq+ 65f
+ addi r4,r4,3
+ addi r6,r6,3
+40: lbzu r0,1(r4)
+ stbu r0,1(r6)
+ bdnz 40b
+65: blr
+EXPORT_SYMBOL(memcpy)
+EXPORT_SYMBOL(memmove)
+EXPORT_SYMBOL_KASAN(memcpy)
+EXPORT_SYMBOL_KASAN(memmove)
+
+generic_memcpy:
+ srwi. r7,r5,3
+ addi r6,r3,-4
+ addi r4,r4,-4
+ beq 2f /* if less than 8 bytes to do */
+ andi. r0,r6,3 /* get dest word aligned */
+ mtctr r7
+ bne 5f
+1: lwz r7,4(r4)
+ lwzu r8,8(r4)
+ stw r7,4(r6)
+ stwu r8,8(r6)
+ bdnz 1b
+ andi. r5,r5,7
+2: cmplwi 0,r5,4
+ blt 3f
+ lwzu r0,4(r4)
+ addi r5,r5,-4
+ stwu r0,4(r6)
+3: cmpwi 0,r5,0
+ beqlr
+ mtctr r5
+ addi r4,r4,3
+ addi r6,r6,3
+4: lbzu r0,1(r4)
+ stbu r0,1(r6)
+ bdnz 4b
+ blr
+5: subfic r0,r0,4
+ mtctr r0
+6: lbz r7,4(r4)
+ addi r4,r4,1
+ stb r7,4(r6)
+ addi r6,r6,1
+ bdnz 6b
+ subf r5,r0,r5
+ rlwinm. r7,r5,32-3,3,31
+ beq 2b
+ mtctr r7
+ b 1b
+
+_GLOBAL(backwards_memcpy)
+ rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */
+ add r6,r3,r5
+ add r4,r4,r5
+ beq 2f
+ andi. r0,r6,3
+ mtctr r7
+ bne 5f
+1: lwz r7,-4(r4)
+ lwzu r8,-8(r4)
+ stw r7,-4(r6)
+ stwu r8,-8(r6)
+ bdnz 1b
+ andi. r5,r5,7
+2: cmplwi 0,r5,4
+ blt 3f
+ lwzu r0,-4(r4)
+ subi r5,r5,4
+ stwu r0,-4(r6)
+3: cmpwi 0,r5,0
+ beqlr
+ mtctr r5
+4: lbzu r0,-1(r4)
+ stbu r0,-1(r6)
+ bdnz 4b
+ blr
+5: mtctr r0
+6: lbzu r7,-1(r4)
+ stbu r7,-1(r6)
+ bdnz 6b
+ subf r5,r0,r5
+ rlwinm. r7,r5,32-3,3,31
+ beq 2b
+ mtctr r7
+ b 1b
+
+_GLOBAL(__copy_tofrom_user)
+ addi r4,r4,-4
+ addi r6,r3,-4
+ neg r0,r3
+ andi. r0,r0,CACHELINE_MASK /* # bytes to start of cache line */
+ beq 58f
+
+ cmplw 0,r5,r0 /* is this more than total to do? */
+ blt 63f /* if not much to do */
+ andi. r8,r0,3 /* get it word-aligned first */
+ mtctr r8
+ beq+ 61f
+70: lbz r9,4(r4) /* do some bytes */
+71: stb r9,4(r6)
+ addi r4,r4,1
+ addi r6,r6,1
+ bdnz 70b
+61: subf r5,r0,r5
+ srwi. r0,r0,2
+ mtctr r0
+ beq 58f
+72: lwzu r9,4(r4) /* do some words */
+73: stwu r9,4(r6)
+ bdnz 72b
+
+ EX_TABLE(70b,100f)
+ EX_TABLE(71b,101f)
+ EX_TABLE(72b,102f)
+ EX_TABLE(73b,103f)
+
+58: srwi. r0,r5,LG_CACHELINE_BYTES /* # complete cachelines */
+ clrlwi r5,r5,32-LG_CACHELINE_BYTES
+ li r11,4
+ beq 63f
+
+ /* Here we decide how far ahead to prefetch the source */
+ li r3,4
+ cmpwi r0,1
+ li r7,0
+ ble 114f
+ li r7,1
+#if MAX_COPY_PREFETCH > 1
+ /* Heuristically, for large transfers we prefetch
+ MAX_COPY_PREFETCH cachelines ahead. For small transfers
+ we prefetch 1 cacheline ahead. */
+ cmpwi r0,MAX_COPY_PREFETCH
+ ble 112f
+ li r7,MAX_COPY_PREFETCH
+112: mtctr r7
+111: dcbt r3,r4
+ addi r3,r3,CACHELINE_BYTES
+ bdnz 111b
+#else
+ dcbt r3,r4
+ addi r3,r3,CACHELINE_BYTES
+#endif /* MAX_COPY_PREFETCH > 1 */
+
+114: subf r8,r7,r0
+ mr r0,r7
+ mtctr r8
+
+53: dcbt r3,r4
+54: dcbz r11,r6
+ EX_TABLE(54b,105f)
+/* the main body of the cacheline loop */
+ COPY_16_BYTES_WITHEX(0)
+#if L1_CACHE_BYTES >= 32
+ COPY_16_BYTES_WITHEX(1)
+#if L1_CACHE_BYTES >= 64
+ COPY_16_BYTES_WITHEX(2)
+ COPY_16_BYTES_WITHEX(3)
+#if L1_CACHE_BYTES >= 128
+ COPY_16_BYTES_WITHEX(4)
+ COPY_16_BYTES_WITHEX(5)
+ COPY_16_BYTES_WITHEX(6)
+ COPY_16_BYTES_WITHEX(7)
+#endif
+#endif
+#endif
+ bdnz 53b
+ cmpwi r0,0
+ li r3,4
+ li r7,0
+ bne 114b
+
+63: srwi. r0,r5,2
+ mtctr r0
+ beq 64f
+30: lwzu r0,4(r4)
+31: stwu r0,4(r6)
+ bdnz 30b
+
+64: andi. r0,r5,3
+ mtctr r0
+ beq+ 65f
+40: lbz r0,4(r4)
+41: stb r0,4(r6)
+ addi r4,r4,1
+ addi r6,r6,1
+ bdnz 40b
+65: li r3,0
+ blr
+
+/* read fault, initial single-byte copy */
+100: li r9,0
+ b 90f
+/* write fault, initial single-byte copy */
+101: li r9,1
+90: subf r5,r8,r5
+ li r3,0
+ b 99f
+/* read fault, initial word copy */
+102: li r9,0
+ b 91f
+/* write fault, initial word copy */
+103: li r9,1
+91: li r3,2
+ b 99f
+
+/*
+ * this stuff handles faults in the cacheline loop and branches to either
+ * 104f (if in read part) or 105f (if in write part), after updating r5
+ */
+ COPY_16_BYTES_EXCODE(0)
+#if L1_CACHE_BYTES >= 32
+ COPY_16_BYTES_EXCODE(1)
+#if L1_CACHE_BYTES >= 64
+ COPY_16_BYTES_EXCODE(2)
+ COPY_16_BYTES_EXCODE(3)
+#if L1_CACHE_BYTES >= 128
+ COPY_16_BYTES_EXCODE(4)
+ COPY_16_BYTES_EXCODE(5)
+ COPY_16_BYTES_EXCODE(6)
+ COPY_16_BYTES_EXCODE(7)
+#endif
+#endif
+#endif
+
+/* read fault in cacheline loop */
+104: li r9,0
+ b 92f
+/* fault on dcbz (effectively a write fault) */
+/* or write fault in cacheline loop */
+105: li r9,1
+92: li r3,LG_CACHELINE_BYTES
+ mfctr r8
+ add r0,r0,r8
+ b 106f
+/* read fault in final word loop */
+108: li r9,0
+ b 93f
+/* write fault in final word loop */
+109: li r9,1
+93: andi. r5,r5,3
+ li r3,2
+ b 99f
+/* read fault in final byte loop */
+110: li r9,0
+ b 94f
+/* write fault in final byte loop */
+111: li r9,1
+94: li r5,0
+ li r3,0
+/*
+ * At this stage the number of bytes not copied is
+ * r5 + (ctr << r3), and r9 is 0 for read or 1 for write.
+ */
+99: mfctr r0
+106: slw r3,r0,r3
+ add. r3,r3,r5
+ beq 120f /* shouldn't happen */
+ cmpwi 0,r9,0
+ bne 120f
+/* for a read fault, first try to continue the copy one byte at a time */
+ mtctr r3
+130: lbz r0,4(r4)
+131: stb r0,4(r6)
+ addi r4,r4,1
+ addi r6,r6,1
+ bdnz 130b
+/* then clear out the destination: r3 bytes starting at 4(r6) */
+132: mfctr r3
+120: blr
+
+ EX_TABLE(30b,108b)
+ EX_TABLE(31b,109b)
+ EX_TABLE(40b,110b)
+ EX_TABLE(41b,111b)
+ EX_TABLE(130b,132b)
+ EX_TABLE(131b,120b)
+
+EXPORT_SYMBOL(__copy_tofrom_user)