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[37.24.206.209]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a93c2775b3csm668996866b.27.2024.10.01.01.50.25 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 01 Oct 2024 01:50:25 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 33e95ba1-7fd2-11ef-99a2-01e77a169b0f DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1727772626; x=1728377426; darn=lists.xenproject.org; h=content-transfer-encoding:in-reply-to:autocrypt:content-language :references:cc:to:from:subject:user-agent:mime-version:date :message-id:from:to:cc:subject:date:message-id:reply-to; bh=LME1v2y5K47DGz0uUCZNveBYET3FXFVivr3ZLArlZP4=; b=TkOrNyykSRdOgaoDKVVAjI61rudCr4SdDLjU29ABOjfMkkuRGqjSdyccxAO7cdBNcP gY4wFdU39114owEj+nd3gXmr2dnAXz0dlldyGmq/FK13DzAme0rdWe5MK1D0jYgSd1eK r6UdkPbu8JJvVKWV0F2cASdTQkBsz9D9YWQufsTrXC7BErJtiv4crqcmRdpIk0vcWF21 pPy5NPrtAzwQU6HIidXHJWUk3PAmfOqzVyGfijq2aKqq4TXrh+Yo2d8mjg1ohLo75gIm SnZV6G88HHnRI9hlNyyzpNkx9Rtf+51IuMT6hk4Mjuxef7bZg1m5JA4oYaEQVFIXXM3o xc4g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1727772626; x=1728377426; h=content-transfer-encoding:in-reply-to:autocrypt:content-language :references:cc:to:from:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=LME1v2y5K47DGz0uUCZNveBYET3FXFVivr3ZLArlZP4=; b=B8Zi6S5Sqa9PLMj0s6p843pBLozjc6pHs5I/q1UuGlxdAzbNUrxf3Y+gRJgFVRe27u Oq3ll2wUX6EnavvVmMnhBV78NA1qoUAN2MHAffpWr1enF0kezM5TgdIcO0UG+y40eUrW fMrbaHB8X1QJ/9O3rNiiXD8CWorv8WOhkdHtKo2WAUoVsdIHdXYunXJfm3cmf9GvX5Cp i+h2iWwBZiFtfMDJHghGUDzwgp2qaXt4VXupjlQxS52BHzzpa5r40GwH0DYCMPhVV4i2 OvSglkdz4Tt4LmKk1bFAEV0n4f4jjFjzPWVUF2VhaGhDOIOerSY19w1NgDC/ZKsj07Xj lObA== X-Gm-Message-State: AOJu0Yy8ipGaOgCflMniQS++RcjDJ6J1SP7dmfclFhGTuCClBct1aSPR m1v6+D6Uo7xfmlAR/lwVpBGOuxpUAKKf6OoK5GwKIhMwmoGURz+yB8HsMatsGIbXY6iUFp4uHq0 = X-Google-Smtp-Source: AGHT+IGRvliJJXGYn8enUcuI2BUAJAWEKNN1SLxvmIKQ4ZJBZ8WCEKTZ8tZ54H0cF+46lkmtTHWbww== X-Received: by 2002:a17:907:2cc5:b0:a86:a1cd:5a8c with SMTP id a640c23a62f3a-a93c49218b7mr1624745366b.22.1727772625801; Tue, 01 Oct 2024 01:50:25 -0700 (PDT) Message-ID: <7d73f0c5-3d16-4cf3-b8de-e45f539e8916@suse.com> Date: Tue, 1 Oct 2024 10:50:25 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: [PATCH v2 5/5] x86/HVM: drop redundant access splitting From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , =?utf-8?q?Roger_Pau_Monn?= =?utf-8?q?=C3=A9?= References: <3294f629-f91f-4b5d-9eb0-40a34aa2ec3e@suse.com> Content-Language: en-US Autocrypt: addr=jbeulich@suse.com; keydata= xsDiBFk3nEQRBADAEaSw6zC/EJkiwGPXbWtPxl2xCdSoeepS07jW8UgcHNurfHvUzogEq5xk hu507c3BarVjyWCJOylMNR98Yd8VqD9UfmX0Hb8/BrA+Hl6/DB/eqGptrf4BSRwcZQM32aZK 7Pj2XbGWIUrZrd70x1eAP9QE3P79Y2oLrsCgbZJfEwCgvz9JjGmQqQkRiTVzlZVCJYcyGGsD /0tbFCzD2h20ahe8rC1gbb3K3qk+LpBtvjBu1RY9drYk0NymiGbJWZgab6t1jM7sk2vuf0Py O9Hf9XBmK0uE9IgMaiCpc32XV9oASz6UJebwkX+zF2jG5I1BfnO9g7KlotcA/v5ClMjgo6Gl MDY4HxoSRu3i1cqqSDtVlt+AOVBJBACrZcnHAUSuCXBPy0jOlBhxPqRWv6ND4c9PH1xjQ3NP nxJuMBS8rnNg22uyfAgmBKNLpLgAGVRMZGaGoJObGf72s6TeIqKJo/LtggAS9qAUiuKVnygo 3wjfkS9A3DRO+SpU7JqWdsveeIQyeyEJ/8PTowmSQLakF+3fote9ybzd880fSmFuIEJldWxp Y2ggPGpiZXVsaWNoQHN1c2UuY29tPsJgBBMRAgAgBQJZN5xEAhsDBgsJCAcDAgQVAggDBBYC AwECHgECF4AACgkQoDSui/t3IH4J+wCfQ5jHdEjCRHj23O/5ttg9r9OIruwAn3103WUITZee e7Sbg12UgcQ5lv7SzsFNBFk3nEQQCACCuTjCjFOUdi5Nm244F+78kLghRcin/awv+IrTcIWF hUpSs1Y91iQQ7KItirz5uwCPlwejSJDQJLIS+QtJHaXDXeV6NI0Uef1hP20+y8qydDiVkv6l IreXjTb7DvksRgJNvCkWtYnlS3mYvQ9NzS9PhyALWbXnH6sIJd2O9lKS1Mrfq+y0IXCP10eS FFGg+Av3IQeFatkJAyju0PPthyTqxSI4lZYuJVPknzgaeuJv/2NccrPvmeDg6Coe7ZIeQ8Yj t0ARxu2xytAkkLCel1Lz1WLmwLstV30g80nkgZf/wr+/BXJW/oIvRlonUkxv+IbBM3dX2OV8 AmRv1ySWPTP7AAMFB/9PQK/VtlNUJvg8GXj9ootzrteGfVZVVT4XBJkfwBcpC/XcPzldjv+3 HYudvpdNK3lLujXeA5fLOH+Z/G9WBc5pFVSMocI71I8bT8lIAzreg0WvkWg5V2WZsUMlnDL9 mpwIGFhlbM3gfDMs7MPMu8YQRFVdUvtSpaAs8OFfGQ0ia3LGZcjA6Ik2+xcqscEJzNH+qh8V m5jjp28yZgaqTaRbg3M/+MTbMpicpZuqF4rnB0AQD12/3BNWDR6bmh+EkYSMcEIpQmBM51qM EKYTQGybRCjpnKHGOxG0rfFY1085mBDZCH5Kx0cl0HVJuQKC+dV2ZY5AqjcKwAxpE75MLFkr wkkEGBECAAkFAlk3nEQCGwwACgkQoDSui/t3IH7nnwCfcJWUDUFKdCsBH/E5d+0ZnMQi+G0A nAuWpQkjM1ASeQwSHEeAWPgskBQL In-Reply-To: <3294f629-f91f-4b5d-9eb0-40a34aa2ec3e@suse.com> With all paths into hvmemul_linear_mmio_access() coming through linear_{read,write}(), there's no need anymore to split accesses at page boundaries there. Leave an assertion, though. Signed-off-by: Jan Beulich --- v2: Replace ASSERT() by more safe construct. --- a/xen/arch/x86/hvm/emulate.c +++ b/xen/arch/x86/hvm/emulate.c @@ -1084,7 +1084,7 @@ static int hvmemul_linear_mmio_access( { struct hvm_vcpu_io *hvio = ¤t->arch.hvm.hvm_io; unsigned long offset = gla & ~PAGE_MASK; - unsigned int chunk, buffer_offset = gla - start; + unsigned int buffer_offset = gla - start; struct hvm_mmio_cache *cache = hvmemul_find_mmio_cache(hvio, start, dir, buffer_offset); paddr_t gpa; @@ -1094,13 +1094,17 @@ static int hvmemul_linear_mmio_access( if ( cache == NULL ) return X86EMUL_UNHANDLEABLE; - chunk = min_t(unsigned int, size, PAGE_SIZE - offset); + if ( size > PAGE_SIZE - offset ) + { + ASSERT_UNREACHABLE(); + return X86EMUL_UNHANDLEABLE; + } if ( known_gpfn ) gpa = pfn_to_paddr(hvio->mmio_gpfn) | offset; else { - rc = hvmemul_linear_to_phys(gla, &gpa, chunk, &one_rep, pfec, + rc = hvmemul_linear_to_phys(gla, &gpa, size, &one_rep, pfec, hvmemul_ctxt); if ( rc != X86EMUL_OKAY ) return rc; @@ -1108,27 +1112,8 @@ static int hvmemul_linear_mmio_access( latch_linear_to_phys(hvio, gla, gpa, dir == IOREQ_WRITE); } - for ( ;; ) - { - rc = hvmemul_phys_mmio_access(cache, gpa, chunk, dir, buffer, buffer_offset); - if ( rc != X86EMUL_OKAY ) - break; - - gla += chunk; - buffer_offset += chunk; - size -= chunk; - - if ( size == 0 ) - break; - - chunk = min_t(unsigned int, size, PAGE_SIZE); - rc = hvmemul_linear_to_phys(gla, &gpa, chunk, &one_rep, pfec, - hvmemul_ctxt); - if ( rc != X86EMUL_OKAY ) - return rc; - } - - return rc; + return hvmemul_phys_mmio_access(cache, gpa, size, dir, buffer, + buffer_offset); } static inline int hvmemul_linear_mmio_read(