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[37.24.206.209]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a8d25a25897sm607259666b.87.2024.09.11.05.27.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 11 Sep 2024 05:28:00 -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: 48e47fb4-7039-11ef-99a1-01e77a169b0f DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1726057680; x=1726662480; 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=XLf/RPw1YIOaKr3H1z6R8wvZ7gEJiJagpvfMhvGlBU0=; b=IoBY8hwjB/nbM0MzFD/3DTXq0/fHD04ZVfUXjhbjmJW55RaKhUF5HNk4cWfRIFwFYx vJfgtGe5/MV8s+MDKvIw8yBj1t47iJ6BUYCTBwVdz+sC95YycdRHkQuHPc67z4sRbQiy W7lskPOGwJePbzvy5376n0eb6x73Sq5e6rWk9lExTFdx6Hfi3maQoXSIpSlevyrz7Szv bu4SMwDMxXPzANLSmzqi1z5cxziD/czF+8ITOTX4dn4Mh2JtMqIxl4DW2sGmSQm9ALXy yhZ7UWwkcihC0+FnQDhiVymsZWJs6aRoy8IMlGYgQTJ3elAPY+8tBez5I+jOKejzKTpB ntdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726057680; x=1726662480; 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=XLf/RPw1YIOaKr3H1z6R8wvZ7gEJiJagpvfMhvGlBU0=; b=o38EOUUs3z3kyp7FZbq+UuKEwvl9lVVACb+VUNpCIjB9cav7atPI7HY7udCUAWV2qh ax8Xmabs7q3leE0eIwUIqMvNaNRRvN6FoXFIW7zhVdtgsMOE+wb/Fzh5JeclgYttkBZ2 Dw56hyrB2Qj8X33KMbKdi5VH+VaH9kssMtJd5S7YcZJe7Dg6B+lVHzQVnFbQyCH5a65m +XVzkyOTdGOdzGqqqgkX1L9vVLVGAJDV0GsL/TDhX3reSuNVXLkHbD3L136bf+9ouigG CBPO8H1xeAZdNjU57Q89EqBTam2JtHSoQHXxuFe4EqqVIgufHJ/sN3Dn4VEvIdKbF4tp 3dWQ== X-Gm-Message-State: AOJu0YwbQfbJ8Vb0z0QflirEdvmGhpXhfkap36okxD/L2dSbZRcC4ToT mj8YueMCgPc9uUE3peeAXQt6bOCu5XG9NM+1MI9chmZB5plAgdGQ8xLtE20HvQfGIRFcFtK8FW8 = X-Google-Smtp-Source: AGHT+IF7+XNohs41mv2XyAhSG7oyRfbWf88mp+hBBrTq6JcaHcBwnaql3WBTXItFJ10ANOC1u6SSMg== X-Received: by 2002:a05:6512:108b:b0:536:536f:5ed4 with SMTP id 2adb3069b0e04-536587a682amr17822718e87.6.1726057680253; Wed, 11 Sep 2024 05:28:00 -0700 (PDT) Message-ID: <08544fc6-bca0-4c69-8f88-3745ed351d53@suse.com> Date: Wed, 11 Sep 2024 14:28:00 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: [PATCH v2 2/9] x86/HVM: drop stdvga's "stdvga" struct member From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , =?utf-8?q?Roger_Pau_Monn?= =?utf-8?q?=C3=A9?= References: 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: Two of its consumers are dead (in compile-time constant conditionals) and the only remaining ones are merely controlling debug logging. Hence the field is now pointless to set, which in particular allows to get rid of the questionable conditional from which the field's value was established (afaict 551ceee97513 ["x86, hvm: stdvga cache always on"] had dropped too much of the earlier extra check that was there, and quite likely further checks were missing). Signed-off-by: Jan Beulich Reviewed-by: Andrew Cooper --- v2: Reduce a (largely pre-existing) comment. Re-base over new earlier patch. --- a/xen/arch/x86/hvm/stdvga.c +++ b/xen/arch/x86/hvm/stdvga.c @@ -103,7 +103,7 @@ static void vram_put(struct hvm_hw_stdvg static int stdvga_outb(uint64_t addr, uint8_t val) { struct hvm_hw_stdvga *s = ¤t->domain->arch.hvm.stdvga; - int rc = 1, prev_stdvga = s->stdvga; + int rc = 1; switch ( addr ) { @@ -132,19 +132,6 @@ static int stdvga_outb(uint64_t addr, ui break; } - /* When in standard vga mode, emulate here all writes to the vram buffer - * so we can immediately satisfy reads without waiting for qemu. */ - s->stdvga = (s->sr[7] == 0x00); - - if ( !prev_stdvga && s->stdvga ) - { - gdprintk(XENLOG_INFO, "entering stdvga mode\n"); - } - else if ( prev_stdvga && !s->stdvga ) - { - gdprintk(XENLOG_INFO, "leaving stdvga mode\n"); - } - return rc; } @@ -425,7 +412,6 @@ static int cf_check stdvga_mem_write( const struct hvm_io_handler *handler, uint64_t addr, uint32_t size, uint64_t data) { - struct hvm_hw_stdvga *s = ¤t->domain->arch.hvm.stdvga; ioreq_t p = { .type = IOREQ_TYPE_COPY, .addr = addr, @@ -436,8 +422,7 @@ static int cf_check stdvga_mem_write( }; struct ioreq_server *srv; - if ( true || !s->stdvga ) - goto done; + goto done; /* Intercept mmio write */ switch ( size ) @@ -498,19 +483,14 @@ static bool cf_check stdvga_mem_accept( spin_lock(&s->lock); - if ( p->dir == IOREQ_WRITE && (p->data_is_ptr || p->count != 1) ) + if ( p->dir != IOREQ_WRITE || p->data_is_ptr || p->count != 1 ) { /* - * We cannot return X86EMUL_UNHANDLEABLE on anything other then the - * first cycle of an I/O. So, since we cannot guarantee to always be - * able to send buffered writes, we have to reject any multi-cycle - * or "indirect" I/O. + * Only accept single direct writes, as that's the only thing we can + * accelerate using buffered ioreq handling. */ goto reject; } - else if ( p->dir == IOREQ_READ && - (true || !s->stdvga) ) - goto reject; /* s->lock intentionally held */ return 1; --- a/xen/arch/x86/include/asm/hvm/io.h +++ b/xen/arch/x86/include/asm/hvm/io.h @@ -115,7 +115,6 @@ struct hvm_hw_stdvga { uint8_t sr[8]; uint8_t gr_index; uint8_t gr[9]; - bool stdvga; uint32_t latch; struct page_info *vram_page[64]; /* shadow of 0xa0000-0xaffff */ spinlock_t lock;