From nobody Mon Feb 9 23:15:45 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F14B3C77B7A for ; Fri, 19 May 2023 09:32:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231633AbjESJc1 (ORCPT ); Fri, 19 May 2023 05:32:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231504AbjESJbn (ORCPT ); Fri, 19 May 2023 05:31:43 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD29819A for ; Fri, 19 May 2023 02:31:41 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 489561FE49; Fri, 19 May 2023 09:31:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1684488700; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7jFwvQhPbaTE9XDubVl2nxiKqr9SWq2+eRDsG198Imk=; b=wVRD7iSaEAGMIsem0FvTs+skpMfBorqD+6Dj7LuL4mo50B0hq1HEZLoXpS+m4DlcdS8fyk UDXmIiO+80HVJDiA0+8dO1FRHo0xLsOdJszd5WOCyl0zDXyUXgPJnh0Ssbl+hyg16AwlLW emq2ohuID6r+vadRtDITcrynRMW9yrU= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1684488700; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7jFwvQhPbaTE9XDubVl2nxiKqr9SWq2+eRDsG198Imk=; b=ZF+ghNd+/0Nl37TJVFjtLOga+jxT8+MYTPfl4IQ5ozptbtFupQvwIOtQfh2vQRVuuLjwHE 1/TsnCk8Ib6rBvAQ== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 2214713A12; Fri, 19 May 2023 09:31:40 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id UBBcB/xBZ2RXJAAAMHmgww (envelope-from ); Fri, 19 May 2023 09:31:40 +0000 From: Takashi Iwai To: alsa-devel@alsa-project.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH 17/36] ALSA: seq: Add snd_seq_expand_var_event_at() helper Date: Fri, 19 May 2023 11:30:55 +0200 Message-Id: <20230519093114.28813-18-tiwai@suse.de> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20230519093114.28813-1-tiwai@suse.de> References: <20230519093114.28813-1-tiwai@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Create a new variant of snd_seq_expand_var_event() for expanding the data starting from the given byte offset. It'll be used by the new UMP sequencer code later. Signed-off-by: Takashi Iwai --- include/sound/seq_kernel.h | 2 + sound/core/seq/seq_memory.c | 86 +++++++++++++++++++++++++++++-------- 2 files changed, 69 insertions(+), 19 deletions(-) diff --git a/include/sound/seq_kernel.h b/include/sound/seq_kernel.h index 658911926f3a..527e7f8ad661 100644 --- a/include/sound/seq_kernel.h +++ b/include/sound/seq_kernel.h @@ -70,6 +70,8 @@ int snd_seq_kernel_client_ctl(int client, unsigned int cm= d, void *arg); typedef int (*snd_seq_dump_func_t)(void *ptr, void *buf, int count); int snd_seq_expand_var_event(const struct snd_seq_event *event, int count,= char *buf, int in_kernel, int size_aligned); +int snd_seq_expand_var_event_at(const struct snd_seq_event *event, int cou= nt, + char *buf, int offset); int snd_seq_dump_var_event(const struct snd_seq_event *event, snd_seq_dump_func_t func, void *private_data); =20 diff --git a/sound/core/seq/seq_memory.c b/sound/core/seq/seq_memory.c index c8d26bce69ff..a8d2db439f86 100644 --- a/sound/core/seq/seq_memory.c +++ b/sound/core/seq/seq_memory.c @@ -63,8 +63,9 @@ static int get_var_len(const struct snd_seq_event *event) return event->data.ext.len & ~SNDRV_SEQ_EXT_MASK; } =20 -int snd_seq_dump_var_event(const struct snd_seq_event *event, - snd_seq_dump_func_t func, void *private_data) +static int dump_var_event(const struct snd_seq_event *event, + snd_seq_dump_func_t func, void *private_data, + int offset, int maxlen) { int len, err; struct snd_seq_event_cell *cell; @@ -72,10 +73,16 @@ int snd_seq_dump_var_event(const struct snd_seq_event *= event, len =3D get_var_len(event); if (len <=3D 0) return len; + if (len <=3D offset) + return 0; + if (maxlen && len > offset + maxlen) + len =3D offset + maxlen; =20 if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) { char buf[32]; char __user *curptr =3D (char __force __user *)event->data.ext.ptr; + curptr +=3D offset; + len -=3D offset; while (len > 0) { int size =3D sizeof(buf); if (len < size) @@ -91,20 +98,35 @@ int snd_seq_dump_var_event(const struct snd_seq_event *= event, return 0; } if (!(event->data.ext.len & SNDRV_SEQ_EXT_CHAINED)) - return func(private_data, event->data.ext.ptr, len); + return func(private_data, event->data.ext.ptr + offset, + len - offset); =20 cell =3D (struct snd_seq_event_cell *)event->data.ext.ptr; for (; len > 0 && cell; cell =3D cell->next) { int size =3D sizeof(struct snd_seq_event); + char *curptr =3D (char *)&cell->event; + + if (offset >=3D size) { + offset -=3D size; + len -=3D size; + continue; + } if (len < size) size =3D len; - err =3D func(private_data, &cell->event, size); + err =3D func(private_data, curptr + offset, size - offset); if (err < 0) return err; + offset =3D 0; len -=3D size; } return 0; } + +int snd_seq_dump_var_event(const struct snd_seq_event *event, + snd_seq_dump_func_t func, void *private_data) +{ + return dump_var_event(event, func, private_data, 0, 0); +} EXPORT_SYMBOL(snd_seq_dump_var_event); =20 =20 @@ -132,11 +154,27 @@ static int seq_copy_in_user(void *ptr, void *src, int= size) return 0; } =20 +static int expand_var_event(const struct snd_seq_event *event, + int offset, int size, char *buf, bool in_kernel) +{ + if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) { + if (! in_kernel) + return -EINVAL; + if (copy_from_user(buf, + (char __force __user *)event->data.ext.ptr + offset, + size)) + return -EFAULT; + return 0; + } + return dump_var_event(event, + in_kernel ? seq_copy_in_kernel : seq_copy_in_user, + &buf, offset, size); +} + int snd_seq_expand_var_event(const struct snd_seq_event *event, int count,= char *buf, int in_kernel, int size_aligned) { - int len, newlen; - int err; + int len, newlen, err; =20 len =3D get_var_len(event); if (len < 0) @@ -146,25 +184,35 @@ int snd_seq_expand_var_event(const struct snd_seq_eve= nt *event, int count, char newlen =3D roundup(len, size_aligned); if (count < newlen) return -EAGAIN; - - if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) { - if (! in_kernel) - return -EINVAL; - if (copy_from_user(buf, (void __force __user *)event->data.ext.ptr, len)) - return -EFAULT; - } else { - err =3D snd_seq_dump_var_event(event, - in_kernel ? seq_copy_in_kernel : seq_copy_in_user, - &buf); - if (err < 0) - return err; - } + err =3D expand_var_event(event, 0, len, buf, in_kernel); + if (err < 0) + return err; if (len !=3D newlen) memset(buf + len, 0, newlen - len); return newlen; } EXPORT_SYMBOL(snd_seq_expand_var_event); =20 +int snd_seq_expand_var_event_at(const struct snd_seq_event *event, int cou= nt, + char *buf, int offset) +{ + int len, err; + + len =3D get_var_len(event); + if (len < 0) + return len; + if (len <=3D offset) + return 0; + len -=3D offset; + if (len > count) + len =3D count; + err =3D expand_var_event(event, offset, count, buf, true); + if (err < 0) + return err; + return len; +} +EXPORT_SYMBOL_GPL(snd_seq_expand_var_event_at); + /* * release this cell, free extended data if available */ --=20 2.35.3