x86, AMD IOMMU: replace memset with __GFP_ZERO for table allocation

This patch removes the memset from the data structure initialization code and
allocate the structures with the __GFP_ZERO flag.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index 0c247032308eb9a7163e35f830ac626fa1b5150e..2efc3d59b7e60cd9aa3b1767f70e29e0028528e4 100644 (file)
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -890,7 +890,7 @@ int __init amd_iommu_init(void)
        ret = -ENOMEM;
 
        /* Device table - directly used by all IOMMUs */
-       amd_iommu_dev_table = (void *)__get_free_pages(GFP_KERNEL,
+       amd_iommu_dev_table = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
                                      get_order(dev_table_size));
        if (amd_iommu_dev_table == NULL)
                goto out;
@@ -914,27 +914,23 @@ int __init amd_iommu_init(void)
         * Protection Domain table - maps devices to protection domains
         * This table has the same size as the rlookup_table
         */
-       amd_iommu_pd_table = (void *)__get_free_pages(GFP_KERNEL,
+       amd_iommu_pd_table = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
                                     get_order(rlookup_table_size));
        if (amd_iommu_pd_table == NULL)
                goto free;
 
-       amd_iommu_pd_alloc_bitmap = (void *)__get_free_pages(GFP_KERNEL,
+       amd_iommu_pd_alloc_bitmap = (void *)__get_free_pages(
+                                           GFP_KERNEL | __GFP_ZERO,
                                            get_order(MAX_DOMAIN_ID/8));
        if (amd_iommu_pd_alloc_bitmap == NULL)
                goto free;
 
        /*
-        * memory is allocated now; initialize the device table with all zeroes
-        * and let all alias entries point to itself
+        * let all alias entries point to itself
         */
-       memset(amd_iommu_dev_table, 0, dev_table_size);
        for (i = 0; i < amd_iommu_last_bdf; ++i)
                amd_iommu_alias_table[i] = i;
 
-       memset(amd_iommu_pd_table, 0, rlookup_table_size);
-       memset(amd_iommu_pd_alloc_bitmap, 0, MAX_DOMAIN_ID / 8);
-
        /*
         * never allocate domain 0 because its used as the non-allocated and
         * error value placeholder