From patchwork Wed Jun 26 05:39:19 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexey Kardashevskiy X-Patchwork-Id: 254580 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [IPv6:::1]) by ozlabs.org (Postfix) with ESMTP id 89FBA2C02EB for ; Wed, 26 Jun 2013 15:41:12 +1000 (EST) Received: from mail-ie0-x22a.google.com (mail-ie0-x22a.google.com [IPv6:2607:f8b0:4001:c03::22a]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 5CF6F2C0805 for ; Wed, 26 Jun 2013 15:39:38 +1000 (EST) Received: by mail-ie0-f170.google.com with SMTP id e11so30306962iej.15 for ; Tue, 25 Jun 2013 22:39:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:x-gm-message-state; bh=xlJkpkkcsz4GCNeTJg3G2FgHKYGFGSnc3lrEs9VtWjQ=; b=IS7o8goZZ9tgMg8uKjloMXrwHUVCoHi45Fls1QXVeA55m1Mi++daI3C2jVyuRyXRGW wzUKE8c5xxDXKr6pL5gWyMsubwRMjwSMJ0j0JOyKCM6bcLiM6PqUvyMmlQ9eWvDpdRjC ZQB0b0A/PT+y8nO38idYJBalMyF3917ZXdooV456KuRY3vHqzh22n2znmxDCZajVRtRS MGZr+8255af4ST7vjAHkhmwJAxBmIBdAWU2GjwKuc0tP5UbLWPzCwvgOmsRPGv55VIof 1d2lmBiHuTephjTliJDq5yNPRwOVmf2/Fm81a54jAF/vn6H46eX16FvcTHZXzk8iD5ZE EqmQ== X-Received: by 10.43.152.78 with SMTP id kv14mr1209968icc.15.1372225175593; Tue, 25 Jun 2013 22:39:35 -0700 (PDT) Received: from ka1.ozlabs.ibm.com (ibmaus65.lnk.telstra.net. [165.228.126.9]) by mx.google.com with ESMTPSA id z15sm5063347igp.0.2013.06.25.22.39.31 for (version=TLSv1.2 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 25 Jun 2013 22:39:34 -0700 (PDT) From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH] powerpc/vfio: Add missing locks for take/release TCE table ownership Date: Wed, 26 Jun 2013 15:39:19 +1000 Message-Id: <1372225159-30187-1-git-send-email-aik@ozlabs.ru> X-Mailer: git-send-email 1.7.10.4 X-Gm-Message-State: ALoCoQmUawLIcpPGbv10CTcV7ojA2B2KcW2gvWDNq1cJ4WqgcCQZu9f0LWVYkGtAu9VqJ/unojHS Cc: Alexey Kardashevskiy , linux-kernel@vger.kernel.org, Paul Mackerras , Anton Blanchard , David Gibson X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" VFIO IOMMU driver for sPAPR TCE locks the whole DMA window by setting ones to iommu_table.it_map. However this was not protected by the locks which other clients of iommu_table use. The patch fixes this. Signed-off-by: Alexey Kardashevskiy --- arch/powerpc/kernel/iommu.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index b20ff17..9f34742 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -1076,25 +1076,41 @@ EXPORT_SYMBOL_GPL(iommu_put_tce_user_mode); int iommu_take_ownership(struct iommu_table *tbl) { unsigned long sz = (tbl->it_size + 7) >> 3; + int i, ret = 0; + + for (i = 0; i < tbl->nr_pools; i++) + spin_lock(&tbl->pools[i].lock); + spin_lock(&tbl->large_pool.lock); if (tbl->it_offset == 0) clear_bit(0, tbl->it_map); if (!bitmap_empty(tbl->it_map, tbl->it_size)) { pr_err("iommu_tce: it_map is not empty"); - return -EBUSY; + ret = -EBUSY; + goto unlock_exit; } memset(tbl->it_map, 0xff, sz); iommu_clear_tces_and_put_pages(tbl, tbl->it_offset, tbl->it_size); - return 0; +unlock_exit: + spin_unlock(&tbl->large_pool.lock); + for (i = 0; i < tbl->nr_pools; i++) + spin_unlock(&tbl->pools[i].lock); + + return ret; } EXPORT_SYMBOL_GPL(iommu_take_ownership); void iommu_release_ownership(struct iommu_table *tbl) { unsigned long sz = (tbl->it_size + 7) >> 3; + int i; + + for (i = 0; i < tbl->nr_pools; i++) + spin_lock(&tbl->pools[i].lock); + spin_lock(&tbl->large_pool.lock); iommu_clear_tces_and_put_pages(tbl, tbl->it_offset, tbl->it_size); memset(tbl->it_map, 0, sz); @@ -1102,6 +1118,11 @@ void iommu_release_ownership(struct iommu_table *tbl) /* Restore bit#0 set by iommu_init_table() */ if (tbl->it_offset == 0) set_bit(0, tbl->it_map); + + spin_unlock(&tbl->large_pool.lock); + for (i = 0; i < tbl->nr_pools; i++) + spin_unlock(&tbl->pools[i].lock); + } EXPORT_SYMBOL_GPL(iommu_release_ownership);