From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9309B35BDA8; Tue, 26 May 2026 22:47:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779835676; cv=none; b=obEzxJmUtIvl6n4y9FmGcI2CB2b0tiiy5hPWVAAb/LOE8E47td6r0bXPXDay0qRGfbgl3c0Xq1yQpNcRzGBeoAfSnI5OQl0XtbDzpFa8WDGR/FkFBX7dl5LCCjEYuf0ZhqNGLHbFQRVN6klxTLDNp0qUFZFGCa8JvEWASo66oe0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779835676; c=relaxed/simple; bh=O5uTN27BF36DAXd06ix4dau0tICxmL5fNLt6KjcYUZU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=LeruYI3wp4kMHUxpgaQdZxCsctEN4J1aMDOJT68pT7PbBkCQ/CCq7GdctcXTSxJZ0zIgU6UPuAAm+yi67rHcPsDyASP8g20oVIPflwxZH5mMiER9y0zo3udTzd6X4L9AmDGQ45N0UYco6rzytOMij/uHubf/ulAgI63SDBt7l+M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=BD4oOGY5; arc=none smtp.client-ip=192.198.163.8 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="BD4oOGY5" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1779835674; x=1811371674; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=O5uTN27BF36DAXd06ix4dau0tICxmL5fNLt6KjcYUZU=; b=BD4oOGY5k5Dx4ySluQmDBHOUnWVaJdSNylnmajP5Ahm0uomPFGDqM7yv qeCy5yG9GUAwdncim9yc6rmF0G/kFkQKTY2teKVZe5Lkp2JWZfmCvueAR K18zhIJQ1iZkLhgyJZ9pFFC8MPFNgB6dGsEXbfNFFnJwcCt32eFMvj/BW YpLW/bUNN8y1O/AOACslDyRrHhd5+TY0fw0ruL5jiMGM9KrNlL8lKYKcW 9yzcKqx5yzcqJwtQXcCYTsE9mwHarrgI2+PLe2c0r0nljeYdAN+iBiy1w Ld+v5F1nmdQFmjECBMclX4JwAvRqe/XnOO3hrSHeHOQQm3uRvnHecoejs A==; X-CSE-ConnectionGUID: C8dry+hXSFK5CsznfNXe7Q== X-CSE-MsgGUID: QjEwPI5PSCKwwRrRF6pCTg== X-IronPort-AV: E=McAfee;i="6800,10657,11798"; a="98237329" X-IronPort-AV: E=Sophos;i="6.24,170,1774335600"; d="scan'208";a="98237329" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 May 2026 15:47:53 -0700 X-CSE-ConnectionGUID: fCeP+KYKSNagPHgmKSZUGw== X-CSE-MsgGUID: xEPJYFdZSYKPO9Nb4iLsZg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,170,1774335600"; d="scan'208";a="241895626" Received: from aduenasd-mobl5.amr.corp.intel.com (HELO [10.125.110.201]) ([10.125.110.201]) by orviesa008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 May 2026 15:47:54 -0700 Message-ID: Date: Tue, 26 May 2026 15:47:53 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 12/12] NTB: epf: Implement db_vector_count/mask for doorbells To: Koichiro Den , Jon Mason , Allen Hubbe , Manivannan Sadhasivam , =?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= , Kishon Vijay Abraham I , Bjorn Helgaas , Frank Li , Jerome Brunet , Lorenzo Pieralisi , Niklas Cassel Cc: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, ntb@lists.linux.dev References: <20260513024923.451765-1-den@valinux.co.jp> <20260513024923.451765-13-den@valinux.co.jp> Content-Language: en-US From: Dave Jiang In-Reply-To: <20260513024923.451765-13-den@valinux.co.jp> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 5/12/26 7:49 PM, Koichiro Den wrote: > Implement .db_vector_count and .db_vector_mask so ntb core/clients can > map doorbell events to per-vector work. > > Report vectors as 0..(db_count - 2) (skipping the unused slot) and return > BIT_ULL(db_vector) for the corresponding doorbell bit. Use > ntb_epf_db_vector_count() for bounds checks in ntb_epf_db_vector_mask(), so > the same lower-bound guard is applied before building the bitmask. > > Signed-off-by: Koichiro Den Reviewed-by: Dave Jiang > --- > Changes since v3: > - Reuse ntb_epf_db_vector_count() from ntb_epf_db_vector_mask() for bounds. > - Return 0 when db_count is below NTB_EPF_MIN_DB_COUNT. > - Drop Reviewed-by tags due to the changes. > > drivers/ntb/hw/epf/ntb_hw_epf.c | 32 ++++++++++++++++++++++++++++++++ > 1 file changed, 32 insertions(+) > > diff --git a/drivers/ntb/hw/epf/ntb_hw_epf.c b/drivers/ntb/hw/epf/ntb_hw_epf.c > index 10618e462229..af5755472842 100644 > --- a/drivers/ntb/hw/epf/ntb_hw_epf.c > +++ b/drivers/ntb/hw/epf/ntb_hw_epf.c > @@ -434,6 +434,36 @@ static u64 ntb_epf_db_valid_mask(struct ntb_dev *ntb) > return ntb_ndev(ntb)->db_valid_mask; > } > > +static int ntb_epf_db_vector_count(struct ntb_dev *ntb) > +{ > + struct ntb_epf_dev *ndev = ntb_ndev(ntb); > + unsigned int db_count = ndev->db_count; > + > + /* > + * db_count includes an extra skipped slot due to the legacy > + * doorbell layout. Expose only the real doorbell vectors. > + */ > + if (db_count < NTB_EPF_MIN_DB_COUNT) > + return 0; > + > + return db_count - 1; > +} > + > +static u64 ntb_epf_db_vector_mask(struct ntb_dev *ntb, int db_vector) > +{ > + int nr_vec; > + > + /* > + * db_count includes one skipped slot in the legacy layout. Valid > + * doorbell vectors are therefore [0 .. (db_count - 2)]. > + */ > + nr_vec = ntb_epf_db_vector_count(ntb); > + if (db_vector < 0 || db_vector >= nr_vec) > + return 0; > + > + return BIT_ULL(db_vector); > +} > + > static int ntb_epf_db_set_mask(struct ntb_dev *ntb, u64 db_bits) > { > return 0; > @@ -568,6 +598,8 @@ static const struct ntb_dev_ops ntb_epf_ops = { > .spad_count = ntb_epf_spad_count, > .peer_mw_count = ntb_epf_peer_mw_count, > .db_valid_mask = ntb_epf_db_valid_mask, > + .db_vector_count = ntb_epf_db_vector_count, > + .db_vector_mask = ntb_epf_db_vector_mask, > .db_set_mask = ntb_epf_db_set_mask, > .mw_set_trans = ntb_epf_mw_set_trans, > .mw_clear_trans = ntb_epf_mw_clear_trans,