From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C51B7135403 for ; Wed, 31 Jan 2024 14:57:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706713081; cv=none; b=LOp2OG0N/ejLeJS5QzVax2TdDcPWQsjPC9NcPf+CA63a4xn9P4J/n1gTdQRTNguxdNeA7hVhetDkh3wWZpTq0eQOCBsBPikJ88Maq78BIZ7hKE+jjxPsaT0jWJ7JMj6tIbTLVsS9X7f+P2Mz7/OZ7JYien8erXoh8BcjTIrlHtw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706713081; c=relaxed/simple; bh=BZa/ahLGkk08b+xnQxlZSNSS4/OSvZFbfYtcadIrVBI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=fU7JElsnO0kbupnLHOndX5iA6V538aQQ34YLlDRPwIJhtvrj7v6N0KlgumfkM3adfiCQ1uHuoNTUJBuddZOkiw212iz/MOpZsMla0mlL+pNai+ehRmS1UVaMkzAG8Mlxij4UUAutu6/wCih1spUIUh3tkohMDAB1aRLlGdrWy9M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 74148DA7; Wed, 31 Jan 2024 06:58:42 -0800 (PST) Received: from e124191.cambridge.arm.com (e124191.cambridge.arm.com [10.1.197.45]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D20183F762; Wed, 31 Jan 2024 06:57:57 -0800 (PST) Date: Wed, 31 Jan 2024 14:57:55 +0000 From: Joey Gouly To: Marc Zyngier Cc: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Catalin Marinas , Will Deacon , Mark Brown Subject: Re: [PATCH v2 10/25] KVM: arm64: nv: Turn encoding ranges into discrete XArray stores Message-ID: <20240131145755.GC2284078@e124191.cambridge.arm.com> References: <20240130204533.693853-1-maz@kernel.org> <20240130204533.693853-11-maz@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240130204533.693853-11-maz@kernel.org> On Tue, Jan 30, 2024 at 08:45:17PM +0000, Marc Zyngier wrote: > In order to be able to store different values for member of an > encoding range, replace xa_store_range() calls with discrete > xa_store() calls and an encoding iterator. > > We end-up using a bit more memory, but we gain some flexibility > that we will make use of shortly. > > Take this opportunity to tidy up the error handling path. > > Signed-off-by: Marc Zyngier > --- > arch/arm64/kvm/emulate-nested.c | 49 ++++++++++++++++++++++++--------- > 1 file changed, 36 insertions(+), 13 deletions(-) > > diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c > index ef46c2e45307..42f5b4483c80 100644 > --- a/arch/arm64/kvm/emulate-nested.c > +++ b/arch/arm64/kvm/emulate-nested.c > @@ -1757,6 +1757,28 @@ static __init void print_nv_trap_error(const struct encoding_to_trap_config *tc, > err); > } > > +static u32 encoding_next(u32 encoding) > +{ > + u8 op0, op1, crn, crm, op2; > + > + op0 = sys_reg_Op0(encoding); > + op1 = sys_reg_Op1(encoding); > + crn = sys_reg_CRn(encoding); > + crm = sys_reg_CRm(encoding); > + op2 = sys_reg_Op2(encoding); > + > + if (op2 < Op2_mask) > + return sys_reg(op0, op1, crn, crm, op2 + 1); > + if (crm < CRm_mask) > + return sys_reg(op0, op1, crn, crm + 1, 0); > + if (crn < CRn_mask) > + return sys_reg(op0, op1, crn + 1, 0, 0); > + if (op1 < Op1_mask) > + return sys_reg(op0, op1 + 1, 0, 0, 0); > + > + return sys_reg(op0 + 1, 0, 0, 0, 0); > +} > + > int __init populate_nv_trap_config(void) > { > int ret = 0; > @@ -1775,23 +1797,18 @@ int __init populate_nv_trap_config(void) > ret = -EINVAL; > } > > - if (cgt->encoding != cgt->end) { > - prev = xa_store_range(&sr_forward_xa, > - cgt->encoding, cgt->end, > - xa_mk_value(cgt->tc.val), > - GFP_KERNEL); > - } else { > - prev = xa_store(&sr_forward_xa, cgt->encoding, > + for (u32 enc = cgt->encoding; enc <= cgt->end; enc = encoding_next(enc)) { > + prev = xa_store(&sr_forward_xa, enc, > xa_mk_value(cgt->tc.val), GFP_KERNEL); > if (prev && !xa_is_err(prev)) { > ret = -EINVAL; > print_nv_trap_error(cgt, "Duplicate CGT", ret); > } > - } > > - if (xa_is_err(prev)) { > - ret = xa_err(prev); > - print_nv_trap_error(cgt, "Failed CGT insertion", ret); > + if (xa_is_err(prev)) { > + ret = xa_err(prev); > + print_nv_trap_error(cgt, "Failed CGT insertion", ret); > + } > } > } > > @@ -1804,6 +1821,7 @@ int __init populate_nv_trap_config(void) > for (int i = 0; i < ARRAY_SIZE(encoding_to_fgt); i++) { > const struct encoding_to_trap_config *fgt = &encoding_to_fgt[i]; > union trap_config tc; > + void *prev; > > if (fgt->tc.fgt >= __NR_FGT_GROUP_IDS__) { > ret = -EINVAL; > @@ -1818,8 +1836,13 @@ int __init populate_nv_trap_config(void) > } > > tc.val |= fgt->tc.val; > - xa_store(&sr_forward_xa, fgt->encoding, > - xa_mk_value(tc.val), GFP_KERNEL); > + prev = xa_store(&sr_forward_xa, fgt->encoding, > + xa_mk_value(tc.val), GFP_KERNEL); > + > + if (xa_is_err(prev)) { > + ret = xa_err(prev); > + print_nv_trap_error(fgt, "Failed FGT insertion", ret); > + } > } > > kvm_info("nv: %ld fine grained trap handlers\n", Tidied up error handling from v1. Reviewed-by: Joey Gouly Thanks, Joey