From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- crypto/async_tx/async_raid6_recov.c | 594 ++++++++++++++++++++++++++++++++++++ 1 file changed, 594 insertions(+) create mode 100644 crypto/async_tx/async_raid6_recov.c (limited to 'crypto/async_tx/async_raid6_recov.c') diff --git a/crypto/async_tx/async_raid6_recov.c b/crypto/async_tx/async_raid6_recov.c new file mode 100644 index 000000000..354b8cd55 --- /dev/null +++ b/crypto/async_tx/async_raid6_recov.c @@ -0,0 +1,594 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Asynchronous RAID-6 recovery calculations ASYNC_TX API. + * Copyright(c) 2009 Intel Corporation + * + * based on raid6recov.c: + * Copyright 2002 H. Peter Anvin + */ +#include +#include +#include +#include +#include +#include +#include + +static struct dma_async_tx_descriptor * +async_sum_product(struct page *dest, unsigned int d_off, + struct page **srcs, unsigned int *src_offs, unsigned char *coef, + size_t len, struct async_submit_ctl *submit) +{ + struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ, + &dest, 1, srcs, 2, len); + struct dma_device *dma = chan ? chan->device : NULL; + struct dmaengine_unmap_data *unmap = NULL; + const u8 *amul, *bmul; + u8 ax, bx; + u8 *a, *b, *c; + + if (dma) + unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOWAIT); + + if (unmap) { + struct device *dev = dma->dev; + dma_addr_t pq[2]; + struct dma_async_tx_descriptor *tx; + enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P; + + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; + unmap->addr[0] = dma_map_page(dev, srcs[0], src_offs[0], + len, DMA_TO_DEVICE); + unmap->addr[1] = dma_map_page(dev, srcs[1], src_offs[1], + len, DMA_TO_DEVICE); + unmap->to_cnt = 2; + + unmap->addr[2] = dma_map_page(dev, dest, d_off, + len, DMA_BIDIRECTIONAL); + unmap->bidi_cnt = 1; + /* engine only looks at Q, but expects it to follow P */ + pq[1] = unmap->addr[2]; + + unmap->len = len; + tx = dma->device_prep_dma_pq(chan, pq, unmap->addr, 2, coef, + len, dma_flags); + if (tx) { + dma_set_unmap(tx, unmap); + async_tx_submit(chan, tx, submit); + dmaengine_unmap_put(unmap); + return tx; + } + + /* could not get a descriptor, unmap and fall through to + * the synchronous path + */ + dmaengine_unmap_put(unmap); + } + + /* run the operation synchronously */ + async_tx_quiesce(&submit->depend_tx); + amul = raid6_gfmul[coef[0]]; + bmul = raid6_gfmul[coef[1]]; + a = page_address(srcs[0]) + src_offs[0]; + b = page_address(srcs[1]) + src_offs[1]; + c = page_address(dest) + d_off; + + while (len--) { + ax = amul[*a++]; + bx = bmul[*b++]; + *c++ = ax ^ bx; + } + + return NULL; +} + +static struct dma_async_tx_descriptor * +async_mult(struct page *dest, unsigned int d_off, struct page *src, + unsigned int s_off, u8 coef, size_t len, + struct async_submit_ctl *submit) +{ + struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ, + &dest, 1, &src, 1, len); + struct dma_device *dma = chan ? chan->device : NULL; + struct dmaengine_unmap_data *unmap = NULL; + const u8 *qmul; /* Q multiplier table */ + u8 *d, *s; + + if (dma) + unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOWAIT); + + if (unmap) { + dma_addr_t dma_dest[2]; + struct device *dev = dma->dev; + struct dma_async_tx_descriptor *tx; + enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P; + + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; + unmap->addr[0] = dma_map_page(dev, src, s_off, + len, DMA_TO_DEVICE); + unmap->to_cnt++; + unmap->addr[1] = dma_map_page(dev, dest, d_off, + len, DMA_BIDIRECTIONAL); + dma_dest[1] = unmap->addr[1]; + unmap->bidi_cnt++; + unmap->len = len; + + /* this looks funny, but the engine looks for Q at + * dma_dest[1] and ignores dma_dest[0] as a dest + * due to DMA_PREP_PQ_DISABLE_P + */ + tx = dma->device_prep_dma_pq(chan, dma_dest, unmap->addr, + 1, &coef, len, dma_flags); + + if (tx) { + dma_set_unmap(tx, unmap); + dmaengine_unmap_put(unmap); + async_tx_submit(chan, tx, submit); + return tx; + } + + /* could not get a descriptor, unmap and fall through to + * the synchronous path + */ + dmaengine_unmap_put(unmap); + } + + /* no channel available, or failed to allocate a descriptor, so + * perform the operation synchronously + */ + async_tx_quiesce(&submit->depend_tx); + qmul = raid6_gfmul[coef]; + d = page_address(dest) + d_off; + s = page_address(src) + s_off; + + while (len--) + *d++ = qmul[*s++]; + + return NULL; +} + +static struct dma_async_tx_descriptor * +__2data_recov_4(int disks, size_t bytes, int faila, int failb, + struct page **blocks, unsigned int *offs, + struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct page *p, *q, *a, *b; + unsigned int p_off, q_off, a_off, b_off; + struct page *srcs[2]; + unsigned int src_offs[2]; + unsigned char coef[2]; + enum async_tx_flags flags = submit->flags; + dma_async_tx_callback cb_fn = submit->cb_fn; + void *cb_param = submit->cb_param; + void *scribble = submit->scribble; + + p = blocks[disks-2]; + p_off = offs[disks-2]; + q = blocks[disks-1]; + q_off = offs[disks-1]; + + a = blocks[faila]; + a_off = offs[faila]; + b = blocks[failb]; + b_off = offs[failb]; + + /* in the 4 disk case P + Pxy == P and Q + Qxy == Q */ + /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ + srcs[0] = p; + src_offs[0] = p_off; + srcs[1] = q; + src_offs[1] = q_off; + coef[0] = raid6_gfexi[failb-faila]; + coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_sum_product(b, b_off, srcs, src_offs, coef, bytes, submit); + + /* Dy = P+Pxy+Dx */ + srcs[0] = p; + src_offs[0] = p_off; + srcs[1] = b; + src_offs[1] = b_off; + init_async_submit(submit, flags | ASYNC_TX_XOR_ZERO_DST, tx, cb_fn, + cb_param, scribble); + tx = async_xor_offs(a, a_off, srcs, src_offs, 2, bytes, submit); + + return tx; + +} + +static struct dma_async_tx_descriptor * +__2data_recov_5(int disks, size_t bytes, int faila, int failb, + struct page **blocks, unsigned int *offs, + struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct page *p, *q, *g, *dp, *dq; + unsigned int p_off, q_off, g_off, dp_off, dq_off; + struct page *srcs[2]; + unsigned int src_offs[2]; + unsigned char coef[2]; + enum async_tx_flags flags = submit->flags; + dma_async_tx_callback cb_fn = submit->cb_fn; + void *cb_param = submit->cb_param; + void *scribble = submit->scribble; + int good_srcs, good, i; + + good_srcs = 0; + good = -1; + for (i = 0; i < disks-2; i++) { + if (blocks[i] == NULL) + continue; + if (i == faila || i == failb) + continue; + good = i; + good_srcs++; + } + BUG_ON(good_srcs > 1); + + p = blocks[disks-2]; + p_off = offs[disks-2]; + q = blocks[disks-1]; + q_off = offs[disks-1]; + g = blocks[good]; + g_off = offs[good]; + + /* Compute syndrome with zero for the missing data pages + * Use the dead data pages as temporary storage for delta p and + * delta q + */ + dp = blocks[faila]; + dp_off = offs[faila]; + dq = blocks[failb]; + dq_off = offs[failb]; + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_memcpy(dp, g, dp_off, g_off, bytes, submit); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_mult(dq, dq_off, g, g_off, + raid6_gfexp[good], bytes, submit); + + /* compute P + Pxy */ + srcs[0] = dp; + src_offs[0] = dp_off; + srcs[1] = p; + src_offs[1] = p_off; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor_offs(dp, dp_off, srcs, src_offs, 2, bytes, submit); + + /* compute Q + Qxy */ + srcs[0] = dq; + src_offs[0] = dq_off; + srcs[1] = q; + src_offs[1] = q_off; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor_offs(dq, dq_off, srcs, src_offs, 2, bytes, submit); + + /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ + srcs[0] = dp; + src_offs[0] = dp_off; + srcs[1] = dq; + src_offs[1] = dq_off; + coef[0] = raid6_gfexi[failb-faila]; + coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_sum_product(dq, dq_off, srcs, src_offs, coef, bytes, submit); + + /* Dy = P+Pxy+Dx */ + srcs[0] = dp; + src_offs[0] = dp_off; + srcs[1] = dq; + src_offs[1] = dq_off; + init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, + cb_param, scribble); + tx = async_xor_offs(dp, dp_off, srcs, src_offs, 2, bytes, submit); + + return tx; +} + +static struct dma_async_tx_descriptor * +__2data_recov_n(int disks, size_t bytes, int faila, int failb, + struct page **blocks, unsigned int *offs, + struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct page *p, *q, *dp, *dq; + unsigned int p_off, q_off, dp_off, dq_off; + struct page *srcs[2]; + unsigned int src_offs[2]; + unsigned char coef[2]; + enum async_tx_flags flags = submit->flags; + dma_async_tx_callback cb_fn = submit->cb_fn; + void *cb_param = submit->cb_param; + void *scribble = submit->scribble; + + p = blocks[disks-2]; + p_off = offs[disks-2]; + q = blocks[disks-1]; + q_off = offs[disks-1]; + + /* Compute syndrome with zero for the missing data pages + * Use the dead data pages as temporary storage for + * delta p and delta q + */ + dp = blocks[faila]; + dp_off = offs[faila]; + blocks[faila] = NULL; + blocks[disks-2] = dp; + offs[disks-2] = dp_off; + dq = blocks[failb]; + dq_off = offs[failb]; + blocks[failb] = NULL; + blocks[disks-1] = dq; + offs[disks-1] = dq_off; + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_gen_syndrome(blocks, offs, disks, bytes, submit); + + /* Restore pointer table */ + blocks[faila] = dp; + offs[faila] = dp_off; + blocks[failb] = dq; + offs[failb] = dq_off; + blocks[disks-2] = p; + offs[disks-2] = p_off; + blocks[disks-1] = q; + offs[disks-1] = q_off; + + /* compute P + Pxy */ + srcs[0] = dp; + src_offs[0] = dp_off; + srcs[1] = p; + src_offs[1] = p_off; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor_offs(dp, dp_off, srcs, src_offs, 2, bytes, submit); + + /* compute Q + Qxy */ + srcs[0] = dq; + src_offs[0] = dq_off; + srcs[1] = q; + src_offs[1] = q_off; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor_offs(dq, dq_off, srcs, src_offs, 2, bytes, submit); + + /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ + srcs[0] = dp; + src_offs[0] = dp_off; + srcs[1] = dq; + src_offs[1] = dq_off; + coef[0] = raid6_gfexi[failb-faila]; + coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_sum_product(dq, dq_off, srcs, src_offs, coef, bytes, submit); + + /* Dy = P+Pxy+Dx */ + srcs[0] = dp; + src_offs[0] = dp_off; + srcs[1] = dq; + src_offs[1] = dq_off; + init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, + cb_param, scribble); + tx = async_xor_offs(dp, dp_off, srcs, src_offs, 2, bytes, submit); + + return tx; +} + +/** + * async_raid6_2data_recov - asynchronously calculate two missing data blocks + * @disks: number of disks in the RAID-6 array + * @bytes: block size + * @faila: first failed drive index + * @failb: second failed drive index + * @blocks: array of source pointers where the last two entries are p and q + * @offs: array of offset for pages in blocks + * @submit: submission/completion modifiers + */ +struct dma_async_tx_descriptor * +async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb, + struct page **blocks, unsigned int *offs, + struct async_submit_ctl *submit) +{ + void *scribble = submit->scribble; + int non_zero_srcs, i; + + BUG_ON(faila == failb); + if (failb < faila) + swap(faila, failb); + + pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes); + + /* if a dma resource is not available or a scribble buffer is not + * available punt to the synchronous path. In the 'dma not + * available' case be sure to use the scribble buffer to + * preserve the content of 'blocks' as the caller intended. + */ + if (!async_dma_find_channel(DMA_PQ) || !scribble) { + void **ptrs = scribble ? scribble : (void **) blocks; + + async_tx_quiesce(&submit->depend_tx); + for (i = 0; i < disks; i++) + if (blocks[i] == NULL) + ptrs[i] = (void *) raid6_empty_zero_page; + else + ptrs[i] = page_address(blocks[i]) + offs[i]; + + raid6_2data_recov(disks, bytes, faila, failb, ptrs); + + async_tx_sync_epilog(submit); + + return NULL; + } + + non_zero_srcs = 0; + for (i = 0; i < disks-2 && non_zero_srcs < 4; i++) + if (blocks[i]) + non_zero_srcs++; + switch (non_zero_srcs) { + case 0: + case 1: + /* There must be at least 2 sources - the failed devices. */ + BUG(); + + case 2: + /* dma devices do not uniformly understand a zero source pq + * operation (in contrast to the synchronous case), so + * explicitly handle the special case of a 4 disk array with + * both data disks missing. + */ + return __2data_recov_4(disks, bytes, faila, failb, + blocks, offs, submit); + case 3: + /* dma devices do not uniformly understand a single + * source pq operation (in contrast to the synchronous + * case), so explicitly handle the special case of a 5 disk + * array with 2 of 3 data disks missing. + */ + return __2data_recov_5(disks, bytes, faila, failb, + blocks, offs, submit); + default: + return __2data_recov_n(disks, bytes, faila, failb, + blocks, offs, submit); + } +} +EXPORT_SYMBOL_GPL(async_raid6_2data_recov); + +/** + * async_raid6_datap_recov - asynchronously calculate a data and the 'p' block + * @disks: number of disks in the RAID-6 array + * @bytes: block size + * @faila: failed drive index + * @blocks: array of source pointers where the last two entries are p and q + * @offs: array of offset for pages in blocks + * @submit: submission/completion modifiers + */ +struct dma_async_tx_descriptor * +async_raid6_datap_recov(int disks, size_t bytes, int faila, + struct page **blocks, unsigned int *offs, + struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct page *p, *q, *dq; + unsigned int p_off, q_off, dq_off; + u8 coef; + enum async_tx_flags flags = submit->flags; + dma_async_tx_callback cb_fn = submit->cb_fn; + void *cb_param = submit->cb_param; + void *scribble = submit->scribble; + int good_srcs, good, i; + struct page *srcs[2]; + unsigned int src_offs[2]; + + pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes); + + /* if a dma resource is not available or a scribble buffer is not + * available punt to the synchronous path. In the 'dma not + * available' case be sure to use the scribble buffer to + * preserve the content of 'blocks' as the caller intended. + */ + if (!async_dma_find_channel(DMA_PQ) || !scribble) { + void **ptrs = scribble ? scribble : (void **) blocks; + + async_tx_quiesce(&submit->depend_tx); + for (i = 0; i < disks; i++) + if (blocks[i] == NULL) + ptrs[i] = (void*)raid6_empty_zero_page; + else + ptrs[i] = page_address(blocks[i]) + offs[i]; + + raid6_datap_recov(disks, bytes, faila, ptrs); + + async_tx_sync_epilog(submit); + + return NULL; + } + + good_srcs = 0; + good = -1; + for (i = 0; i < disks-2; i++) { + if (i == faila) + continue; + if (blocks[i]) { + good = i; + good_srcs++; + if (good_srcs > 1) + break; + } + } + BUG_ON(good_srcs == 0); + + p = blocks[disks-2]; + p_off = offs[disks-2]; + q = blocks[disks-1]; + q_off = offs[disks-1]; + + /* Compute syndrome with zero for the missing data page + * Use the dead data page as temporary storage for delta q + */ + dq = blocks[faila]; + dq_off = offs[faila]; + blocks[faila] = NULL; + blocks[disks-1] = dq; + offs[disks-1] = dq_off; + + /* in the 4-disk case we only need to perform a single source + * multiplication with the one good data block. + */ + if (good_srcs == 1) { + struct page *g = blocks[good]; + unsigned int g_off = offs[good]; + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); + tx = async_memcpy(p, g, p_off, g_off, bytes, submit); + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); + tx = async_mult(dq, dq_off, g, g_off, + raid6_gfexp[good], bytes, submit); + } else { + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); + tx = async_gen_syndrome(blocks, offs, disks, bytes, submit); + } + + /* Restore pointer table */ + blocks[faila] = dq; + offs[faila] = dq_off; + blocks[disks-1] = q; + offs[disks-1] = q_off; + + /* calculate g^{-faila} */ + coef = raid6_gfinv[raid6_gfexp[faila]]; + + srcs[0] = dq; + src_offs[0] = dq_off; + srcs[1] = q; + src_offs[1] = q_off; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor_offs(dq, dq_off, srcs, src_offs, 2, bytes, submit); + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_mult(dq, dq_off, dq, dq_off, coef, bytes, submit); + + srcs[0] = p; + src_offs[0] = p_off; + srcs[1] = dq; + src_offs[1] = dq_off; + init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, + cb_param, scribble); + tx = async_xor_offs(p, p_off, srcs, src_offs, 2, bytes, submit); + + return tx; +} +EXPORT_SYMBOL_GPL(async_raid6_datap_recov); + +MODULE_AUTHOR("Dan Williams "); +MODULE_DESCRIPTION("asynchronous RAID-6 recovery api"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3