From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 678D92472A5 for ; Fri, 17 Oct 2025 07:45:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.135.223.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760687110; cv=none; b=CTHj4TeUNv9zXF34o2eRYY9BdlI6AiVN3u2RlhYKGKkgEkULYO/aiYM2uFtotEZKdoHD+h2oZGon+R0fKolx35JcXnEF4yKezL2sp85dpKHVT4YyZjOeJVQNXl+JtHMYrxWz4usBZUatRObJNwLXyUyAN9ApSuAu6sr5d4rAQ2Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760687110; c=relaxed/simple; bh=XIy2C9gA/e0GWhJeOuxDYULeuw1Cr2Dk1imRwaTojhY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=unVGz56o07oVrrh3MOcouYSNazu6dboObxdih5lVMBvUlKpoSBnXx0JMgxcdwzAHAmP1zcDvQWM9NEJmFN+qxvrq0Y3eB/PlYllDCdk3Ae8xZWsz2Sy7z7lNt0vRNK0nzj4hV56GiaJt93TrVAD9ijgHjNRsoP8CGbfikmra6Nw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=suse.de; spf=pass smtp.mailfrom=suse.de; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b=emCtYV2r; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b=rSZnOvWl; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b=emCtYV2r; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b=rSZnOvWl; arc=none smtp.client-ip=195.135.223.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b="emCtYV2r"; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b="rSZnOvWl"; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b="emCtYV2r"; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b="rSZnOvWl" Received: from imap1.dmz-prg2.suse.org (unknown [10.150.64.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 7B1A51FD6D; Fri, 17 Oct 2025 07:45:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1760687105; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=Z7z+6Rva6qEu6P4DiQFx1RV9ZjLaO7H2OATZ97Ien5c=; b=emCtYV2rnDQUvPBnVBzb73Yi2Sv/JIXNCgDWT2Kij+TtDY0HaLwU6LAN4AXm0rJTIXvDuK 9KoHly7+WGz+wlVDLKMB0KwlxtxzKqLQTzV1GJMQmUN6bXrFjLHmNN3T6Q5GpK9A3UdgVk Eie8wipfQL5aP9ajG7R9hcEICZhH6WA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1760687105; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=Z7z+6Rva6qEu6P4DiQFx1RV9ZjLaO7H2OATZ97Ien5c=; b=rSZnOvWlznQFOVGrOeBRfOw8rMbuSW3vqkFrATe9MxbawtpUkNckYJgQtdAmF7uhIaM3dt tKjo235iVmM2ULBA== Authentication-Results: smtp-out2.suse.de; none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1760687105; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=Z7z+6Rva6qEu6P4DiQFx1RV9ZjLaO7H2OATZ97Ien5c=; b=emCtYV2rnDQUvPBnVBzb73Yi2Sv/JIXNCgDWT2Kij+TtDY0HaLwU6LAN4AXm0rJTIXvDuK 9KoHly7+WGz+wlVDLKMB0KwlxtxzKqLQTzV1GJMQmUN6bXrFjLHmNN3T6Q5GpK9A3UdgVk Eie8wipfQL5aP9ajG7R9hcEICZhH6WA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1760687105; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=Z7z+6Rva6qEu6P4DiQFx1RV9ZjLaO7H2OATZ97Ien5c=; b=rSZnOvWlznQFOVGrOeBRfOw8rMbuSW3vqkFrATe9MxbawtpUkNckYJgQtdAmF7uhIaM3dt tKjo235iVmM2ULBA== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 1DB33136C6; Fri, 17 Oct 2025 07:45:05 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id OTcMBgH08WhKSAAAD6G6ig (envelope-from ); Fri, 17 Oct 2025 07:45:05 +0000 Message-ID: <8cb49212-99e7-4eae-ab8c-a95f3c81854d@suse.de> Date: Fri, 17 Oct 2025 09:45:04 +0200 Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] iosys_map: Make dst a const in iosys_map_memcpy_to() To: Lyude Paul , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich , "open list:RUST:Keyword:b(?i:rust)b" References: <20251016202455.2750217-1-lyude@redhat.com> Content-Language: en-US From: Thomas Zimmermann Autocrypt: addr=tzimmermann@suse.de; keydata= xsBNBFs50uABCADEHPidWt974CaxBVbrIBwqcq/WURinJ3+2WlIrKWspiP83vfZKaXhFYsdg XH47fDVbPPj+d6tQrw5lPQCyqjwrCPYnq3WlIBnGPJ4/jreTL6V+qfKRDlGLWFjZcsrPJGE0 BeB5BbqP5erN1qylK9i3gPoQjXGhpBpQYwRrEyQyjuvk+Ev0K1Jc5tVDeJAuau3TGNgah4Yc hdHm3bkPjz9EErV85RwvImQ1dptvx6s7xzwXTgGAsaYZsL8WCwDaTuqFa1d1jjlaxg6+tZsB 9GluwvIhSezPgnEmimZDkGnZRRSFiGP8yjqTjjWuf0bSj5rUnTGiyLyRZRNGcXmu6hjlABEB AAHNJ1Rob21hcyBaaW1tZXJtYW5uIDx0emltbWVybWFubkBzdXNlLmRlPsLAjgQTAQgAOAIb AwULCQgHAgYVCgkICwIEFgIDAQIeAQIXgBYhBHIX+6yM6c9jRKFo5WgNwR1TC3ojBQJftODH AAoJEGgNwR1TC3ojx1wH/0hKGWugiqDgLNXLRD/4TfHBEKmxIrmfu9Z5t7vwUKfwhFL6hqvo lXPJJKQpQ2z8+X2vZm/slsLn7J1yjrOsoJhKABDi+3QWWSGkaGwRJAdPVVyJMfJRNNNIKwVb U6B1BkX2XDKDGffF4TxlOpSQzdtNI/9gleOoUA8+jy8knnDYzjBNOZqLG2FuTdicBXblz0Mf vg41gd9kCwYXDnD91rJU8tzylXv03E75NCaTxTM+FBXPmsAVYQ4GYhhgFt8S2UWMoaaABLDe 7l5FdnLdDEcbmd8uLU2CaG4W2cLrUaI4jz2XbkcPQkqTQ3EB67hYkjiEE6Zy3ggOitiQGcqp j//OwE0EWznS4AEIAMYmP4M/V+T5RY5at/g7rUdNsLhWv1APYrh9RQefODYHrNRHUE9eosYb T6XMryR9hT8XlGOYRwKWwiQBoWSDiTMo/Xi29jUnn4BXfI2px2DTXwc22LKtLAgTRjP+qbU6 3Y0xnQN29UGDbYgyyK51DW3H0If2a3JNsheAAK+Xc9baj0LGIc8T9uiEWHBnCH+RdhgATnWW GKdDegUR5BkDfDg5O/FISymJBHx2Dyoklv5g4BzkgqTqwmaYzsl8UxZKvbaxq0zbehDda8lv hFXodNFMAgTLJlLuDYOGLK2AwbrS3Sp0AEbkpdJBb44qVlGm5bApZouHeJ/+n+7r12+lqdsA EQEAAcLAdgQYAQgAIAIbDBYhBHIX+6yM6c9jRKFo5WgNwR1TC3ojBQJftOH6AAoJEGgNwR1T C3ojVSkIALpAPkIJPQoURPb1VWjh34l0HlglmYHvZszJWTXYwavHR8+k6Baa6H7ufXNQtThR yIxJrQLW6rV5lm7TjhffEhxVCn37+cg0zZ3j7zIsSS0rx/aMwi6VhFJA5hfn3T0TtrijKP4A SAQO9xD1Zk9/61JWk8OysuIh7MXkl0fxbRKWE93XeQBhIJHQfnc+YBLprdnxR446Sh8Wn/2D Ya8cavuWf2zrB6cZurs048xe0UbSW5AOSo4V9M0jzYI4nZqTmPxYyXbm30Kvmz0rYVRaitYJ 4kyYYMhuULvrJDMjZRvaNe52tkKAvMevcGdt38H4KSVXAylqyQOW5zvPc4/sq9c= In-Reply-To: <20251016202455.2750217-1-lyude@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Level: X-Spamd-Result: default: False [-2.80 / 50.00]; BAYES_HAM(-3.00)[100.00%]; SUSPICIOUS_RECIPS(1.50)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; TAGGED_RCPT(0.00)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; MIME_TRACE(0.00)[0:+]; RCPT_COUNT_TWELVE(0.00)[14]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCVD_TLS_ALL(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com,protonmail.com]; TO_DN_SOME(0.00)[]; FROM_HAS_DN(0.00)[]; FREEMAIL_CC(0.00)[kernel.org,gmail.com,garyguo.net,protonmail.com,google.com,umich.edu,vger.kernel.org]; MID_RHS_MATCH_FROM(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo,suse.de:mid] X-Spam-Flag: NO X-Spam-Score: -2.80 Hi Am 16.10.25 um 22:24 schrieb Lyude Paul: > A drive-by fix I discovered when writing up bindings for iosys_mem for > rust: while iosys_map_memcpy_to() does modify the memory pointed to by the > iosys_map, it doesn't modify the actual iosys_map struct at all. > > As such, let's add a const qualifier to this function. As far as I'm concerned, the non-const is intentional. Because it's the destination, so expect it to be written. Thus passing arguments that are already const is most likely an error. And because I'd like to keep the option of doing something more complicated within iosys_map (e.g., some temp memory for handling I/O) and const might get in the way. Best regads Thomas > > Signed-off-by: Lyude Paul > --- > include/linux/iosys-map.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/iosys-map.h b/include/linux/iosys-map.h > index 3e85afe794c0a..0ececbba04b3a 100644 > --- a/include/linux/iosys-map.h > +++ b/include/linux/iosys-map.h > @@ -278,7 +278,7 @@ static inline void iosys_map_clear(struct iosys_map *map) > * system memory. Depending on the buffer's location, the helper picks the > * correct method of accessing the memory. > */ > -static inline void iosys_map_memcpy_to(struct iosys_map *dst, size_t dst_offset, > +static inline void iosys_map_memcpy_to(const struct iosys_map *dst, size_t dst_offset, > const void *src, size_t len) > { > if (dst->is_iomem) > > base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787 -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstrasse 146, 90461 Nuernberg, Germany GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman HRB 36809 (AG Nuernberg)