Date: Fri, 17 Jun 2022 19:40:31 GMT From: Dmitry Chagin <dchagin@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Subject: git: 30c8127e3c76 - stable/13 - linux(4): Implement futex_op for arm64. Message-ID: <202206171940.25HJeVV1025914@gitrepo.freebsd.org>
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The branch stable/13 has been updated by dchagin: URL: https://cgit.FreeBSD.org/src/commit/?id=30c8127e3c76905d05473d1c6200b69cde0bd9e0 commit 30c8127e3c76905d05473d1c6200b69cde0bd9e0 Author: Dmitry Chagin <dchagin@FreeBSD.org> AuthorDate: 2022-05-15 17:49:42 +0000 Commit: Dmitry Chagin <dchagin@FreeBSD.org> CommitDate: 2022-06-17 19:35:19 +0000 linux(4): Implement futex_op for arm64. It's mostly modeled like the Linux does. Differential revision: https://reviews.freebsd.org/D35154 MFC after: 2 weeks (cherry picked from commit 3bae1cd68a2ac3e2c37d54cf550e01257dfb1a04) --- sys/arm64/linux/linux_support.s | 130 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 123 insertions(+), 7 deletions(-) diff --git a/sys/arm64/linux/linux_support.s b/sys/arm64/linux/linux_support.s index 1048e9579627..933930b5096f 100644 --- a/sys/arm64/linux/linux_support.s +++ b/sys/arm64/linux/linux_support.s @@ -2,6 +2,7 @@ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (C) 2018 Turing Robotic Industries Inc. + * Copyright (C) 2022 Dmitry Chagin <dchagin@FreeBSD.org> * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -27,36 +28,151 @@ * $FreeBSD$ */ -#include "linux_assym.h" #include <machine/asm.h> +__FBSDID("$FreeBSD$"); + +#include <machine/param.h> +#include <machine/vmparam.h> + +#include <sys/errno.h> #include "assym.inc" +.macro check_user_access user_arg, limit, bad_addr_func + ldr x7, =(\limit) + cmp x\user_arg, x7 + b.cs \bad_addr_func +.endm + +futex_fault: + SET_FAULT_HANDLER(xzr, x1) + EXIT_USER_ACCESS_CHECK(w0, x1) +futex_fault_nopcb: + mov x0, #EFAULT + ret + +#define LINUX_FUTEX_MAX_LOOPS 128 + /* - * LINUXTODO: implement futex_* + * int oparg, uint32_t *uaddr, int *oldval + * + * Return 0 on success, errno on failure, + * EAGAIN is returned if LL/SC operation fails. + * + * XXX. VM_MAXUSER_ADDRESS is not applicable here, should be replaced + * by something like LINUX_SHAREDPAGE. */ +/* (int *)uaddr2 = oparg */ ENTRY(futex_xchgl) - brk #0 + check_user_access 1, (VM_MAXUSER_ADDRESS-3), futex_fault_nopcb + adr x9, futex_fault /* Load the fault handler */ + SET_FAULT_HANDLER(x9, x4) /* And set it */ + ENTER_USER_ACCESS(w9, x4) + mov w5, #LINUX_FUTEX_MAX_LOOPS + prfm pstl1strm, [x1] + mov w6, w0 /* Save oparg */ +1: ldxr w4, [x1] /* Load oldval from uaddr */ + stlxr w0, w6, [x1] /* Store oparg to uaddr */ + cbz w0, 3f /* Exit on success */ + sub w5, w5, w0 /* Dec loop counter, w0 is 1 */ + cbnz w5, 1b /* Loop */ + mov x0, #EAGAIN /* Store of newval failed */ +3: dmb ish + EXIT_USER_ACCESS(w9) + SET_FAULT_HANDLER(xzr, x9) /* Reset the fault handler */ + str w4, [x2] /* Store oldval */ ret END(futex_xchgl) +/* (int *)uaddr2 += oparg */ ENTRY(futex_addl) - brk #0 + check_user_access 1, (VM_MAXUSER_ADDRESS-3), futex_fault_nopcb + adr x9, futex_fault + SET_FAULT_HANDLER(x9, x4) + ENTER_USER_ACCESS(w9, x4) + mov w5, #LINUX_FUTEX_MAX_LOOPS + prfm pstl1strm, [x1] + mov w6, w0 +1: ldxr w4, [x1] + add w3, w4, w6 /* oldval + oparg */ + stlxr w0, w3, [x1] + cbz w0, 3f + sub w5, w5, w0 + cbnz w5, 1b + mov x0, #EAGAIN +3: dmb ish + EXIT_USER_ACCESS(w9) + SET_FAULT_HANDLER(xzr, x9) + str w4, [x2] ret END(futex_addl) +/* (int *)uaddr2 |= oparg */ ENTRY(futex_orl) - brk #0 + check_user_access 1, (VM_MAXUSER_ADDRESS-3), futex_fault_nopcb + adr x9, futex_fault + SET_FAULT_HANDLER(x9, x4) + ENTER_USER_ACCESS(w9, x4) + mov w5, #LINUX_FUTEX_MAX_LOOPS + prfm pstl1strm, [x1] + mov w6, w0 +1: ldxr w4, [x1] + orr w3, w4, w6 /* oldavl |= oparg */ + stlxr w0, w3, [x1] + cbz w0, 3f + sub w5, w5, w0 + cbnz w5, 1b + mov x0, #EAGAIN +3: dmb ish + EXIT_USER_ACCESS(w9) + SET_FAULT_HANDLER(xzr, x9) + str w4, [x2] ret END(futex_orl) +/* (int *)uaddr2 &= oparg */ ENTRY(futex_andl) - brk #0 + check_user_access 1, (VM_MAXUSER_ADDRESS-3), futex_fault_nopcb + adr x9, futex_fault + SET_FAULT_HANDLER(x9, x4) + ENTER_USER_ACCESS(w9, x4) + mov w5, #LINUX_FUTEX_MAX_LOOPS + prfm pstl1strm, [x1] + mov w6, w0 +1: ldxr w4, [x1] + and w3, w4, w6 /* oldval &= oparg */ + stlxr w0, w3, [x1] + cbz w0, 3f + sub w5, w5, w0 + cbnz w5, 1b + mov x0, #EAGAIN +3: dmb ish + EXIT_USER_ACCESS(w9) + SET_FAULT_HANDLER(xzr, x9) + str w4, [x2] ret END(futex_andl) +/* (int *)uaddr2 ^= oparg */ ENTRY(futex_xorl) - brk #0 + check_user_access 1, (VM_MAXUSER_ADDRESS-3), futex_fault_nopcb + adr x9, futex_fault + SET_FAULT_HANDLER(x9, x4) + ENTER_USER_ACCESS(w9, x4) + mov w5, #LINUX_FUTEX_MAX_LOOPS + prfm pstl1strm, [x1] + mov w6, w0 +1: ldxr w4, [x1] + eor w3, w4, w6 /* oldval ^= oparg */ + stlxr w0, w3, [x1] + cbz w0, 3f + sub w5, w5, w0 + cbnz w5, 1b + mov x0, #EAGAIN +3: dmb ish + EXIT_USER_ACCESS(w9) + SET_FAULT_HANDLER(xzr, x9) + str w4, [x2] ret END(futex_xorl)
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