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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /lib/reed_solomon/decode_rs.c | |
download | linux-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 '')
-rw-r--r-- | lib/reed_solomon/decode_rs.c | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/lib/reed_solomon/decode_rs.c b/lib/reed_solomon/decode_rs.c new file mode 100644 index 000000000..805de84ae --- /dev/null +++ b/lib/reed_solomon/decode_rs.c @@ -0,0 +1,326 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Generic Reed Solomon encoder / decoder library + * + * Copyright 2002, Phil Karn, KA9Q + * May be used under the terms of the GNU General Public License (GPL) + * + * Adaption to the kernel by Thomas Gleixner (tglx@linutronix.de) + * + * Generic data width independent code which is included by the wrappers. + */ +{ + struct rs_codec *rs = rsc->codec; + int deg_lambda, el, deg_omega; + int i, j, r, k, pad; + int nn = rs->nn; + int nroots = rs->nroots; + int fcr = rs->fcr; + int prim = rs->prim; + int iprim = rs->iprim; + uint16_t *alpha_to = rs->alpha_to; + uint16_t *index_of = rs->index_of; + uint16_t u, q, tmp, num1, num2, den, discr_r, syn_error; + int count = 0; + int num_corrected; + uint16_t msk = (uint16_t) rs->nn; + + /* + * The decoder buffers are in the rs control struct. They are + * arrays sized [nroots + 1] + */ + uint16_t *lambda = rsc->buffers + RS_DECODE_LAMBDA * (nroots + 1); + uint16_t *syn = rsc->buffers + RS_DECODE_SYN * (nroots + 1); + uint16_t *b = rsc->buffers + RS_DECODE_B * (nroots + 1); + uint16_t *t = rsc->buffers + RS_DECODE_T * (nroots + 1); + uint16_t *omega = rsc->buffers + RS_DECODE_OMEGA * (nroots + 1); + uint16_t *root = rsc->buffers + RS_DECODE_ROOT * (nroots + 1); + uint16_t *reg = rsc->buffers + RS_DECODE_REG * (nroots + 1); + uint16_t *loc = rsc->buffers + RS_DECODE_LOC * (nroots + 1); + + /* Check length parameter for validity */ + pad = nn - nroots - len; + BUG_ON(pad < 0 || pad >= nn - nroots); + + /* Does the caller provide the syndrome ? */ + if (s != NULL) { + for (i = 0; i < nroots; i++) { + /* The syndrome is in index form, + * so nn represents zero + */ + if (s[i] != nn) + goto decode; + } + + /* syndrome is zero, no errors to correct */ + return 0; + } + + /* form the syndromes; i.e., evaluate data(x) at roots of + * g(x) */ + for (i = 0; i < nroots; i++) + syn[i] = (((uint16_t) data[0]) ^ invmsk) & msk; + + for (j = 1; j < len; j++) { + for (i = 0; i < nroots; i++) { + if (syn[i] == 0) { + syn[i] = (((uint16_t) data[j]) ^ + invmsk) & msk; + } else { + syn[i] = ((((uint16_t) data[j]) ^ + invmsk) & msk) ^ + alpha_to[rs_modnn(rs, index_of[syn[i]] + + (fcr + i) * prim)]; + } + } + } + + for (j = 0; j < nroots; j++) { + for (i = 0; i < nroots; i++) { + if (syn[i] == 0) { + syn[i] = ((uint16_t) par[j]) & msk; + } else { + syn[i] = (((uint16_t) par[j]) & msk) ^ + alpha_to[rs_modnn(rs, index_of[syn[i]] + + (fcr+i)*prim)]; + } + } + } + s = syn; + + /* Convert syndromes to index form, checking for nonzero condition */ + syn_error = 0; + for (i = 0; i < nroots; i++) { + syn_error |= s[i]; + s[i] = index_of[s[i]]; + } + + if (!syn_error) { + /* if syndrome is zero, data[] is a codeword and there are no + * errors to correct. So return data[] unmodified + */ + return 0; + } + + decode: + memset(&lambda[1], 0, nroots * sizeof(lambda[0])); + lambda[0] = 1; + + if (no_eras > 0) { + /* Init lambda to be the erasure locator polynomial */ + lambda[1] = alpha_to[rs_modnn(rs, + prim * (nn - 1 - (eras_pos[0] + pad)))]; + for (i = 1; i < no_eras; i++) { + u = rs_modnn(rs, prim * (nn - 1 - (eras_pos[i] + pad))); + for (j = i + 1; j > 0; j--) { + tmp = index_of[lambda[j - 1]]; + if (tmp != nn) { + lambda[j] ^= + alpha_to[rs_modnn(rs, u + tmp)]; + } + } + } + } + + for (i = 0; i < nroots + 1; i++) + b[i] = index_of[lambda[i]]; + + /* + * Begin Berlekamp-Massey algorithm to determine error+erasure + * locator polynomial + */ + r = no_eras; + el = no_eras; + while (++r <= nroots) { /* r is the step number */ + /* Compute discrepancy at the r-th step in poly-form */ + discr_r = 0; + for (i = 0; i < r; i++) { + if ((lambda[i] != 0) && (s[r - i - 1] != nn)) { + discr_r ^= + alpha_to[rs_modnn(rs, + index_of[lambda[i]] + + s[r - i - 1])]; + } + } + discr_r = index_of[discr_r]; /* Index form */ + if (discr_r == nn) { + /* 2 lines below: B(x) <-- x*B(x) */ + memmove (&b[1], b, nroots * sizeof (b[0])); + b[0] = nn; + } else { + /* 7 lines below: T(x) <-- lambda(x)-discr_r*x*b(x) */ + t[0] = lambda[0]; + for (i = 0; i < nroots; i++) { + if (b[i] != nn) { + t[i + 1] = lambda[i + 1] ^ + alpha_to[rs_modnn(rs, discr_r + + b[i])]; + } else + t[i + 1] = lambda[i + 1]; + } + if (2 * el <= r + no_eras - 1) { + el = r + no_eras - el; + /* + * 2 lines below: B(x) <-- inv(discr_r) * + * lambda(x) + */ + for (i = 0; i <= nroots; i++) { + b[i] = (lambda[i] == 0) ? nn : + rs_modnn(rs, index_of[lambda[i]] + - discr_r + nn); + } + } else { + /* 2 lines below: B(x) <-- x*B(x) */ + memmove(&b[1], b, nroots * sizeof(b[0])); + b[0] = nn; + } + memcpy(lambda, t, (nroots + 1) * sizeof(t[0])); + } + } + + /* Convert lambda to index form and compute deg(lambda(x)) */ + deg_lambda = 0; + for (i = 0; i < nroots + 1; i++) { + lambda[i] = index_of[lambda[i]]; + if (lambda[i] != nn) + deg_lambda = i; + } + + if (deg_lambda == 0) { + /* + * deg(lambda) is zero even though the syndrome is non-zero + * => uncorrectable error detected + */ + return -EBADMSG; + } + + /* Find roots of error+erasure locator polynomial by Chien search */ + memcpy(®[1], &lambda[1], nroots * sizeof(reg[0])); + count = 0; /* Number of roots of lambda(x) */ + for (i = 1, k = iprim - 1; i <= nn; i++, k = rs_modnn(rs, k + iprim)) { + q = 1; /* lambda[0] is always 0 */ + for (j = deg_lambda; j > 0; j--) { + if (reg[j] != nn) { + reg[j] = rs_modnn(rs, reg[j] + j); + q ^= alpha_to[reg[j]]; + } + } + if (q != 0) + continue; /* Not a root */ + + if (k < pad) { + /* Impossible error location. Uncorrectable error. */ + return -EBADMSG; + } + + /* store root (index-form) and error location number */ + root[count] = i; + loc[count] = k; + /* If we've already found max possible roots, + * abort the search to save time + */ + if (++count == deg_lambda) + break; + } + if (deg_lambda != count) { + /* + * deg(lambda) unequal to number of roots => uncorrectable + * error detected + */ + return -EBADMSG; + } + /* + * Compute err+eras evaluator poly omega(x) = s(x)*lambda(x) (modulo + * x**nroots). in index form. Also find deg(omega). + */ + deg_omega = deg_lambda - 1; + for (i = 0; i <= deg_omega; i++) { + tmp = 0; + for (j = i; j >= 0; j--) { + if ((s[i - j] != nn) && (lambda[j] != nn)) + tmp ^= + alpha_to[rs_modnn(rs, s[i - j] + lambda[j])]; + } + omega[i] = index_of[tmp]; + } + + /* + * Compute error values in poly-form. num1 = omega(inv(X(l))), num2 = + * inv(X(l))**(fcr-1) and den = lambda_pr(inv(X(l))) all in poly-form + * Note: we reuse the buffer for b to store the correction pattern + */ + num_corrected = 0; + for (j = count - 1; j >= 0; j--) { + num1 = 0; + for (i = deg_omega; i >= 0; i--) { + if (omega[i] != nn) + num1 ^= alpha_to[rs_modnn(rs, omega[i] + + i * root[j])]; + } + + if (num1 == 0) { + /* Nothing to correct at this position */ + b[j] = 0; + continue; + } + + num2 = alpha_to[rs_modnn(rs, root[j] * (fcr - 1) + nn)]; + den = 0; + + /* lambda[i+1] for i even is the formal derivative + * lambda_pr of lambda[i] */ + for (i = min(deg_lambda, nroots - 1) & ~1; i >= 0; i -= 2) { + if (lambda[i + 1] != nn) { + den ^= alpha_to[rs_modnn(rs, lambda[i + 1] + + i * root[j])]; + } + } + + b[j] = alpha_to[rs_modnn(rs, index_of[num1] + + index_of[num2] + + nn - index_of[den])]; + num_corrected++; + } + + /* + * We compute the syndrome of the 'error' and check that it matches + * the syndrome of the received word + */ + for (i = 0; i < nroots; i++) { + tmp = 0; + for (j = 0; j < count; j++) { + if (b[j] == 0) + continue; + + k = (fcr + i) * prim * (nn-loc[j]-1); + tmp ^= alpha_to[rs_modnn(rs, index_of[b[j]] + k)]; + } + + if (tmp != alpha_to[s[i]]) + return -EBADMSG; + } + + /* + * Store the error correction pattern, if a + * correction buffer is available + */ + if (corr && eras_pos) { + j = 0; + for (i = 0; i < count; i++) { + if (b[i]) { + corr[j] = b[i]; + eras_pos[j++] = loc[i] - pad; + } + } + } else if (data && par) { + /* Apply error to data and parity */ + for (i = 0; i < count; i++) { + if (loc[i] < (nn - nroots)) + data[loc[i] - pad] ^= b[i]; + else + par[loc[i] - pad - len] ^= b[i]; + } + } + + return num_corrected; +} |