From patchwork Wed Feb 16 13:13:29 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 12748548 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53C4DC433F5 for ; Wed, 16 Feb 2022 13:18:17 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E715E6B0071; Wed, 16 Feb 2022 08:18:16 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E490A6B0082; Wed, 16 Feb 2022 08:18:16 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CEAE86B0085; Wed, 16 Feb 2022 08:18:16 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0067.hostedemail.com [216.40.44.67]) by kanga.kvack.org (Postfix) with ESMTP id C108C6B0071 for ; Wed, 16 Feb 2022 08:18:16 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 8553B181AC9C6 for ; Wed, 16 Feb 2022 13:18:16 +0000 (UTC) X-FDA: 79148696592.24.B7977EB Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf14.hostedemail.com (Postfix) with ESMTP id 029A1100009 for ; Wed, 16 Feb 2022 13:18:15 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5FDF06164A; Wed, 16 Feb 2022 13:18:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42A0CC340EF; Wed, 16 Feb 2022 13:18:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645017494; bh=ej3RO+uva7QeaPXgpaaXqjsnYYGnLyMzDoW4XSnGyLE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NDlehbZC0qKdOHJSk18Tzs4KsuOAOFp+dZUSUNraclRO6wJLjf+YMSl4MTtSCPYAH Xjw/z2CpAB/NGrCDwts99qKiGUlRcVfZRz1c9cVzj4VeTUpTiMH2N9eWKP/PH92Z/Z loiDImjqPjkFR0MMOsTn4NTfDjsCIGHReLJkWhMh6oXFyRXGsaXELg0PjlW95qCM/J 5L0XmS477B7GcvXg25Kfy48cgAQPlltBCSWLZkR33fR/egmFcOYah5NmsIAE7+DUwM cvGjNjEQKDqzqnFUHpIVrD/CEAbhKeuZFIjk/WUEd9+g3hx7ZR7hQOmPyOMvlL1gzt I6oEPTAFtclKQ== From: Arnd Bergmann To: Linus Torvalds , Christoph Hellwig , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, arnd@arndb.de, linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk Cc: linux@armlinux.org.uk, will@kernel.org, guoren@kernel.org, bcain@codeaurora.org, geert@linux-m68k.org, monstr@monstr.eu, tsbogend@alpha.franken.de, nickhu@andestech.com, green.hu@gmail.com, dinguyen@kernel.org, shorne@gmail.com, deller@gmx.de, mpe@ellerman.id.au, peterz@infradead.org, mingo@redhat.com, mark.rutland@arm.com, hca@linux.ibm.com, dalias@libc.org, davem@davemloft.net, richard@nod.at, x86@kernel.org, jcmvbkbc@gmail.com, ebiederm@xmission.com, akpm@linux-foundation.org, ardb@kernel.org, linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, openrisc@lists.librecores.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, linux-xtensa@linux-xtensa.org Subject: [PATCH v2 15/18] sparc64: remove CONFIG_SET_FS support Date: Wed, 16 Feb 2022 14:13:29 +0100 Message-Id: <20220216131332.1489939-16-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20220216131332.1489939-1-arnd@kernel.org> References: <20220216131332.1489939-1-arnd@kernel.org> MIME-Version: 1.0 X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 029A1100009 X-Stat-Signature: rz9ceddot4uf3p1nbhcqa8ht13ee7ah5 X-Rspam-User: Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=NDlehbZC; spf=pass (imf14.hostedemail.com: domain of arnd@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=arnd@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-HE-Tag: 1645017495-176555 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Arnd Bergmann sparc64 uses address space identifiers to differentiate between kernel and user space, using ASI_P for kernel threads but ASI_AIUS for normal user space, with the option of changing between them. As nothing really changes the ASI any more, just hardcode ASI_AIUS everywhere. Kernel threads are not allowed to access __user pointers anyway. Signed-off-by: Arnd Bergmann --- arch/sparc/include/asm/processor_64.h | 4 ---- arch/sparc/include/asm/switch_to_64.h | 4 +--- arch/sparc/include/asm/thread_info_64.h | 4 +--- arch/sparc/include/asm/uaccess_64.h | 20 +------------------- arch/sparc/kernel/process_64.c | 12 ------------ arch/sparc/kernel/traps_64.c | 2 -- arch/sparc/lib/NGmemcpy.S | 3 +-- arch/sparc/mm/init_64.c | 7 ++++--- 8 files changed, 8 insertions(+), 48 deletions(-) diff --git a/arch/sparc/include/asm/processor_64.h b/arch/sparc/include/asm/processor_64.h index ae851e8fce4c..89850dff6b03 100644 --- a/arch/sparc/include/asm/processor_64.h +++ b/arch/sparc/include/asm/processor_64.h @@ -47,10 +47,6 @@ #ifndef __ASSEMBLY__ -typedef struct { - unsigned char seg; -} mm_segment_t; - /* The Sparc processor specific thread struct. */ /* XXX This should die, everything can go into thread_info now. */ struct thread_struct { diff --git a/arch/sparc/include/asm/switch_to_64.h b/arch/sparc/include/asm/switch_to_64.h index b1d4e2e3210f..14f3c49bfdbc 100644 --- a/arch/sparc/include/asm/switch_to_64.h +++ b/arch/sparc/include/asm/switch_to_64.h @@ -20,10 +20,8 @@ do { \ */ #define switch_to(prev, next, last) \ do { save_and_clear_fpu(); \ - /* If you are tempted to conditionalize the following */ \ - /* so that ASI is only written if it changes, think again. */ \ __asm__ __volatile__("wr %%g0, %0, %%asi" \ - : : "r" (task_thread_info(next)->current_ds));\ + : : "r" (ASI_AIUS)); \ trap_block[current_thread_info()->cpu].thread = \ task_thread_info(next); \ __asm__ __volatile__( \ diff --git a/arch/sparc/include/asm/thread_info_64.h b/arch/sparc/include/asm/thread_info_64.h index 8047a9caab2f..1a44372e2bc0 100644 --- a/arch/sparc/include/asm/thread_info_64.h +++ b/arch/sparc/include/asm/thread_info_64.h @@ -46,7 +46,7 @@ struct thread_info { struct pt_regs *kregs; int preempt_count; /* 0 => preemptable, <0 => BUG */ __u8 new_child; - __u8 current_ds; + __u8 __pad; __u16 cpu; unsigned long *utraps; @@ -81,7 +81,6 @@ struct thread_info { #define TI_KREGS 0x00000028 #define TI_PRE_COUNT 0x00000030 #define TI_NEW_CHILD 0x00000034 -#define TI_CURRENT_DS 0x00000035 #define TI_CPU 0x00000036 #define TI_UTRAPS 0x00000038 #define TI_REG_WINDOW 0x00000040 @@ -116,7 +115,6 @@ struct thread_info { #define INIT_THREAD_INFO(tsk) \ { \ .task = &tsk, \ - .current_ds = ASI_P, \ .preempt_count = INIT_PREEMPT_COUNT, \ .kregs = (struct pt_regs *)(init_stack+THREAD_SIZE)-1 \ } diff --git a/arch/sparc/include/asm/uaccess_64.h b/arch/sparc/include/asm/uaccess_64.h index 59b9a545df23..94266a5c5b04 100644 --- a/arch/sparc/include/asm/uaccess_64.h +++ b/arch/sparc/include/asm/uaccess_64.h @@ -12,33 +12,15 @@ #include #include +#include /* * Sparc64 is segmented, though more like the M68K than the I386. * We use the secondary ASI to address user memory, which references a * completely different VM map, thus there is zero chance of the user * doing something queer and tricking us into poking kernel memory. - * - * What is left here is basically what is needed for the other parts of - * the kernel that expect to be able to manipulate, erum, "segments". - * Or perhaps more properly, permissions. - * - * "For historical reasons, these macros are grossly misnamed." -Linus */ -#define KERNEL_DS ((mm_segment_t) { ASI_P }) -#define USER_DS ((mm_segment_t) { ASI_AIUS }) /* har har har */ - -#define get_fs() ((mm_segment_t){(current_thread_info()->current_ds)}) - -#include - -#define set_fs(val) \ -do { \ - current_thread_info()->current_ds = (val).seg; \ - __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \ -} while(0) - /* * Test whether a block of memory is a valid user space address. * Returns 0 if the range is valid, nonzero otherwise. diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c index f5b2cac8669f..9a2ceb080ac9 100644 --- a/arch/sparc/kernel/process_64.c +++ b/arch/sparc/kernel/process_64.c @@ -106,18 +106,13 @@ static void show_regwindow32(struct pt_regs *regs) { struct reg_window32 __user *rw; struct reg_window32 r_w; - mm_segment_t old_fs; __asm__ __volatile__ ("flushw"); rw = compat_ptr((unsigned int)regs->u_regs[14]); - old_fs = get_fs(); - set_fs (USER_DS); if (copy_from_user (&r_w, rw, sizeof(r_w))) { - set_fs (old_fs); return; } - set_fs (old_fs); printk("l0: %08x l1: %08x l2: %08x l3: %08x " "l4: %08x l5: %08x l6: %08x l7: %08x\n", r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3], @@ -136,7 +131,6 @@ static void show_regwindow(struct pt_regs *regs) struct reg_window __user *rw; struct reg_window *rwk; struct reg_window r_w; - mm_segment_t old_fs; if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) { __asm__ __volatile__ ("flushw"); @@ -145,14 +139,10 @@ static void show_regwindow(struct pt_regs *regs) rwk = (struct reg_window *) (regs->u_regs[14] + STACK_BIAS); if (!(regs->tstate & TSTATE_PRIV)) { - old_fs = get_fs(); - set_fs (USER_DS); if (copy_from_user (&r_w, rw, sizeof(r_w))) { - set_fs (old_fs); return; } rwk = &r_w; - set_fs (old_fs); } } else { show_regwindow32(regs); @@ -598,7 +588,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg, memset(child_trap_frame, 0, child_stack_sz); __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = (current_pt_regs()->tstate + 1) & TSTATE_CWP; - t->current_ds = ASI_P; t->kregs->u_regs[UREG_G1] = sp; /* function */ t->kregs->u_regs[UREG_G2] = arg; return 0; @@ -613,7 +602,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg, t->kregs->u_regs[UREG_FP] = sp; __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = (regs->tstate + 1) & TSTATE_CWP; - t->current_ds = ASI_AIUS; if (sp != regs->u_regs[UREG_FP]) { unsigned long csp; diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c index 21077821f427..5b4de4a89dec 100644 --- a/arch/sparc/kernel/traps_64.c +++ b/arch/sparc/kernel/traps_64.c @@ -2857,8 +2857,6 @@ void __init trap_init(void) TI_PRE_COUNT != offsetof(struct thread_info, preempt_count) || TI_NEW_CHILD != offsetof(struct thread_info, new_child) || - TI_CURRENT_DS != offsetof(struct thread_info, - current_ds) || TI_KUNA_REGS != offsetof(struct thread_info, kern_una_regs) || TI_KUNA_INSN != offsetof(struct thread_info, diff --git a/arch/sparc/lib/NGmemcpy.S b/arch/sparc/lib/NGmemcpy.S index 8e4d22a6ba0b..ee51c1230689 100644 --- a/arch/sparc/lib/NGmemcpy.S +++ b/arch/sparc/lib/NGmemcpy.S @@ -10,8 +10,7 @@ #include #define GLOBAL_SPARE %g7 #define RESTORE_ASI(TMP) \ - ldub [%g6 + TI_CURRENT_DS], TMP; \ - wr TMP, 0x0, %asi; + wr %g0, ASI_AIUS, %asi #else #define GLOBAL_SPARE %g5 #define RESTORE_ASI(TMP) \ diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index 1b23639e2fcd..8b1911591581 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -709,9 +709,10 @@ static void __init inherit_prom_mappings(void) void prom_world(int enter) { - if (!enter) - set_fs(get_fs()); - + /* + * No need to change the address space any more, just flush + * the register windows + */ __asm__ __volatile__("flushw"); }