From nobody Mon Feb 9 08:56:11 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6D3ED235BF4 for ; Wed, 26 Feb 2025 18:46:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740595562; cv=none; b=Aq53SXdrI8J7PkU4iK+y5EnLUWM9YxHXUE2/uOJy43uwVAvOVCSnaft/ZDoe0VLSF8lx3XsaBFylRseDywYuX83wLN1+nGiJ2eipimBY87PDfO3e8ef83fXEBJz14VNqzPHsiqANmK5VAT08uCd9GPIdaHctDBQX2S78VcR/wio= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740595562; c=relaxed/simple; bh=GGboBiUAnzqzEkcPJLhVinGFyNQd+KTlEDa9DnpBz6o=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=EqKpqqmugpL2nyjSEsXwsvCzVdSfqBGciNZqafme84t3qwXZB8XWq8u3HrTL4EHkl/zyByg66A9sU9tGPhljBXAbtrTi3r5wRaEC+vzLnszrg7S4bjdSCYBTWv9fiSpRcMrqJati9TtQv+PD5nQa1M+fm8gnD91ytftr3XXEjAc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IVxzKg8Q; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IVxzKg8Q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93C59C4CEE7; Wed, 26 Feb 2025 18:46:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740595561; bh=GGboBiUAnzqzEkcPJLhVinGFyNQd+KTlEDa9DnpBz6o=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=IVxzKg8Qheh7Ol+EGR/xq1SAommDIl0ENloP8OFTqRtlC8TLqPwVmh/WT0edIMQZz WjPHVr2l8skhk0j0CEC4+wffRBmG9l9lcZ/GS60dxIUMfQWfhWYnrYeGQYRS7/6SEz 9HFSkipZBVNrHv82eQwamSsOT2z9nGVK22cI2RGj+5bAFsNGOO/z/KYNrlTWf4xkCp g8+STH3jyTAqdDCKqmYmlyQGE4B3lkS7d4DQ9VkRGw00aaK8BzWbab4AIJaacu/Oo1 tLZdDRhqveGv3hf+HISYVCkYDOGcFIHKqMMWcqTRh9HnM0rVCXNAew5rgC5loNXoJ4 JPXhI84MMCISg== From: Daniel Wagner Date: Wed, 26 Feb 2025 19:45:54 +0100 Subject: [PATCH 02/11] nvmet-fcloop: add ref counting to lport Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250226-nvmet-fcloop-v1-2-c0bd83d43e6a@kernel.org> References: <20250226-nvmet-fcloop-v1-0-c0bd83d43e6a@kernel.org> In-Reply-To: <20250226-nvmet-fcloop-v1-0-c0bd83d43e6a@kernel.org> To: James Smart , Christoph Hellwig , Sagi Grimberg , Chaitanya Kulkarni Cc: Hannes Reinecke , Keith Busch , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, Daniel Wagner X-Mailer: b4 0.14.2 The fcloop_lport objects live time is controlled by the user interface add_local_port and del_local_port. nport, rport and tport objects are pointing to the lport objects but here is no clear tracking. Let's introduce an explicit ref counter for the lport objects and prepare the stage for restructuring how lports are used. Signed-off-by: Daniel Wagner Reviewed-by: Hannes Reinecke --- drivers/nvme/target/fcloop.c | 47 +++++++++++++++++++++++++++++++++-------= ---- 1 file changed, 35 insertions(+), 12 deletions(-) diff --git a/drivers/nvme/target/fcloop.c b/drivers/nvme/target/fcloop.c index 5493677a948d34391c7c08055dfefd91cc3ff33f..ca46830d46ecbaae21f3ee3e69a= a7d52905abcae 100644 --- a/drivers/nvme/target/fcloop.c +++ b/drivers/nvme/target/fcloop.c @@ -208,6 +208,7 @@ struct fcloop_lport { struct nvme_fc_local_port *localport; struct list_head lport_list; struct completion unreg_done; + struct kref ref; }; =20 struct fcloop_lport_priv { @@ -1000,6 +1001,32 @@ fcloop_fcp_abort(struct nvme_fc_local_port *localpor= t, } } =20 +static void +fcloop_lport_free(struct kref *ref) +{ + struct fcloop_lport *lport =3D + container_of(ref, struct fcloop_lport, ref); + unsigned long flags; + + spin_lock_irqsave(&fcloop_lock, flags); + list_del(&lport->lport_list); + spin_unlock_irqrestore(&fcloop_lock, flags); + + kfree(lport); +} + +static void +fcloop_lport_put(struct fcloop_lport *lport) +{ + kref_put(&lport->ref, fcloop_lport_free); +} + +static int +fcloop_lport_get(struct fcloop_lport *lport) +{ + return kref_get_unless_zero(&lport->ref); +} + static void fcloop_nport_free(struct kref *ref) { @@ -1145,6 +1172,7 @@ fcloop_create_local_port(struct device *dev, struct d= evice_attribute *attr, =20 lport->localport =3D localport; INIT_LIST_HEAD(&lport->lport_list); + kref_init(&lport->ref); =20 spin_lock_irqsave(&fcloop_lock, flags); list_add_tail(&lport->lport_list, &fcloop_lports); @@ -1161,13 +1189,6 @@ fcloop_create_local_port(struct device *dev, struct = device_attribute *attr, return ret ? ret : count; } =20 - -static void -__unlink_local_port(struct fcloop_lport *lport) -{ - list_del(&lport->lport_list); -} - static int __wait_localport_unreg(struct fcloop_lport *lport) { @@ -1180,7 +1201,7 @@ __wait_localport_unreg(struct fcloop_lport *lport) if (!ret) wait_for_completion(&lport->unreg_done); =20 - kfree(lport); + fcloop_lport_put(lport); =20 return ret; } @@ -1204,8 +1225,9 @@ fcloop_delete_local_port(struct device *dev, struct d= evice_attribute *attr, list_for_each_entry(tlport, &fcloop_lports, lport_list) { if (tlport->localport->node_name =3D=3D nodename && tlport->localport->port_name =3D=3D portname) { + if (!fcloop_lport_get(tlport)) + break; lport =3D tlport; - __unlink_local_port(lport); break; } } @@ -1215,6 +1237,7 @@ fcloop_delete_local_port(struct device *dev, struct d= evice_attribute *attr, return -ENOENT; =20 ret =3D __wait_localport_unreg(lport); + fcloop_lport_put(lport); =20 return ret ? ret : count; } @@ -1640,17 +1663,17 @@ static void __exit fcloop_exit(void) for (;;) { lport =3D list_first_entry_or_null(&fcloop_lports, typeof(*lport), lport_list); - if (!lport) + if (!lport || !fcloop_lport_get(lport)) break; =20 - __unlink_local_port(lport); - spin_unlock_irqrestore(&fcloop_lock, flags); =20 ret =3D __wait_localport_unreg(lport); if (ret) pr_warn("%s: Failed deleting local port\n", __func__); =20 + fcloop_lport_put(lport); + spin_lock_irqsave(&fcloop_lock, flags); } =20 --=20 2.48.1