Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754246AbaACANU (ORCPT ); Thu, 2 Jan 2014 19:13:20 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:23713 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753990AbaACAHq (ORCPT ); Thu, 2 Jan 2014 19:07:46 -0500 From: Yinghai Lu To: "H. Peter Anvin" , Tony Luck , Bjorn Helgaas , "Rafael J. Wysocki" , x86 Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, Yinghai Lu , Joerg Roedel , Donald Dutile Subject: [PATCH v2 04/10] IOMMU: iommu_unique_seq_id() Date: Thu, 2 Jan 2014 16:08:11 -0800 Message-Id: <1388707697-16800-5-git-send-email-yinghai@kernel.org> X-Mailer: git-send-email 1.8.4 In-Reply-To: <1388707697-16800-1-git-send-email-yinghai@kernel.org> References: <1388707697-16800-1-git-send-email-yinghai@kernel.org> X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1733 Lines: 71 So for hot-remove/hot-add will reuse seq_id. Signed-off-by: Yinghai Lu Cc: Joerg Roedel Cc: Donald Dutile --- drivers/iommu/dmar.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index a14867c..f5e0718 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -785,11 +785,22 @@ out: return err; } +static DECLARE_BITMAP(iommu_allocated, 1024); + +static int iommu_unique_seq_id(void) +{ + int id; + + id = find_first_zero_bit(iommu_allocated, 1024); + __set_bit(id, iommu_allocated); + + return id; +} + int alloc_iommu(struct dmar_drhd_unit *drhd) { struct intel_iommu *iommu; u32 ver, sts; - static int iommu_allocated = 0; int agaw = 0; int msagaw = 0; int err; @@ -803,7 +814,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd) if (!iommu) return -ENOMEM; - iommu->seq_id = iommu_allocated++; + iommu->seq_id = iommu_unique_seq_id(); sprintf (iommu->name, "dmar%d", iommu->seq_id); err = map_iommu(iommu, drhd->reg_base_addr); @@ -855,6 +866,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd) err_unmap: unmap_iommu(iommu); error: + __clear_bit(iommu->seq_id, iommu_allocated); kfree(iommu); return err; } @@ -869,6 +881,8 @@ void free_iommu(struct intel_iommu *iommu) if (iommu->reg) unmap_iommu(iommu); + __clear_bit(iommu->seq_id, iommu_allocated); + kfree(iommu); } -- 1.8.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/