iommu/vt-d: Introduce macro for_each_dev_scope() to walk device scope entries

Introduce for_each_dev_scope()/for_each_active_dev_scope() to walk
{active} device scope entries. This will help following RCU lock
related patches.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 58dde75c52293d773b67fd4fc4dd24147626765c..4ae6df27ad5d861ecb4bde612e955e07f208fa5d 100644 (file)
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -170,9 +170,12 @@ int __init dmar_parse_dev_scope(void *start, void *end, int *cnt,
 
 void dmar_free_dev_scope(struct pci_dev ***devices, int *cnt)
 {
+       int i;
+       struct pci_dev *tmp_dev;
+
        if (*devices && *cnt) {
-               while (--*cnt >= 0)
-                       pci_dev_put((*devices)[*cnt]);
+               for_each_active_dev_scope(*devices, *cnt, i, tmp_dev)
+                       pci_dev_put(tmp_dev);
                kfree(*devices);
                *devices = NULL;
                *cnt = 0;
@@ -402,10 +405,11 @@ static int dmar_pci_device_match(struct pci_dev *devices[], int cnt,
                          struct pci_dev *dev)
 {
        int index;
+       struct pci_dev *tmp;
 
        while (dev) {
-               for (index = 0; index < cnt; index++)
-                       if (dev == devices[index])
+               for_each_active_dev_scope(devices, cnt, index, tmp)
+                       if (dev == tmp)
                                return 1;
 
                /* Check our parent */
@@ -452,7 +456,7 @@ int __init dmar_dev_scope_init(void)
        if (list_empty(&dmar_drhd_units))
                goto fail;
 
-       list_for_each_entry(drhd, &dmar_drhd_units, list) {
+       for_each_drhd_unit(drhd) {
                ret = dmar_parse_dev(drhd);
                if (ret)
                        goto fail;

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 7732c43871fa9124671f7246a87bddc5538d7e0a..bb98e37f2cf720f091b3c453f41149fbbaacc32f 100644 (file)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -654,29 +654,31 @@ static void domain_update_iommu_cap(struct dmar_domain *domain)
 static struct intel_iommu *device_to_iommu(int segment, u8 bus, u8 devfn)
 {
        struct dmar_drhd_unit *drhd = NULL;
+       struct intel_iommu *iommu;
+       struct pci_dev *dev;
        int i;
 
-       for_each_active_drhd_unit(drhd) {
+       for_each_active_iommu(iommu, drhd) {
                if (segment != drhd->segment)
                        continue;
 
-               for (i = 0; i < drhd->devices_cnt; i++) {
-                       if (drhd->devices[i] &&
-                           drhd->devices[i]->bus->number == bus &&
-                           drhd->devices[i]->devfn == devfn)
-                               return drhd->iommu;
-                       if (drhd->devices[i] &&
-                           drhd->devices[i]->subordinate &&
-                           drhd->devices[i]->subordinate->number <= bus &&
-                           drhd->devices[i]->subordinate->busn_res.end >= bus)
-                               return drhd->iommu;
+               for_each_active_dev_scope(drhd->devices,
+                                         drhd->devices_cnt, i, dev) {
+                       if (dev->bus->number == bus && dev->devfn == devfn)
+                               goto out;
+                       if (dev->subordinate &&
+                           dev->subordinate->number <= bus &&
+                           dev->subordinate->busn_res.end >= bus)
+                               goto out;
                }
 
                if (drhd->include_all)
-                       return drhd->iommu;
+                       goto out;
        }
+       iommu = NULL;
+out:
 
-       return NULL;
+       return iommu;
 }
 
 static void domain_flush_cache(struct dmar_domain *domain,
@@ -2333,17 +2335,19 @@ static int domain_add_dev_info(struct dmar_domain *domain,
 static bool device_has_rmrr(struct pci_dev *dev)
 {
        struct dmar_rmrr_unit *rmrr;
+       struct pci_dev *tmp;
        int i;
 
        for_each_rmrr_units(rmrr) {
-               for (i = 0; i < rmrr->devices_cnt; i++) {
-                       /*
-                        * Return TRUE if this RMRR contains the device that
-                        * is passed in.
-                        */
-                       if (rmrr->devices[i] == dev)
+               /*
+                * Return TRUE if this RMRR contains the device that
+                * is passed in.
+                */
+               for_each_active_dev_scope(rmrr->devices,
+                                         rmrr->devices_cnt, i, tmp)
+                       if (tmp == dev) {
                                return true;
-               }
+                       }
        }
        return false;
 }
@@ -2593,14 +2597,9 @@ static int __init init_dmars(void)
         */
        printk(KERN_INFO "IOMMU: Setting RMRR:\n");
        for_each_rmrr_units(rmrr) {
-               for (i = 0; i < rmrr->devices_cnt; i++) {
-                       pdev = rmrr->devices[i];
-                       /*
-                        * some BIOS lists non-exist devices in DMAR
-                        * table.
-                        */
-                       if (!pdev)
-                               continue;
+               /* some BIOS lists non-exist devices in DMAR table. */
+               for_each_active_dev_scope(rmrr->devices, rmrr->devices_cnt,
+                                         i, pdev) {
                        ret = iommu_prepare_rmrr_dev(rmrr, pdev);
                        if (ret)
                                printk(KERN_ERR
@@ -3288,13 +3287,14 @@ DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SNB, quir
 static void __init init_no_remapping_devices(void)
 {
        struct dmar_drhd_unit *drhd;
+       struct pci_dev *dev;
+       int i;
 
        for_each_drhd_unit(drhd) {
                if (!drhd->include_all) {
-                       int i;
-                       for (i = 0; i < drhd->devices_cnt; i++)
-                               if (drhd->devices[i] != NULL)
-                                       break;
+                       for_each_active_dev_scope(drhd->devices,
+                                                 drhd->devices_cnt, i, dev)
+                               break;
                        /* ignore DMAR unit if no pci devices exist */
                        if (i == drhd->devices_cnt)
                                drhd->ignored = 1;
@@ -3302,15 +3302,13 @@ static void __init init_no_remapping_devices(void)
        }
 
        for_each_active_drhd_unit(drhd) {
-               int i;
                if (drhd->include_all)
                        continue;
 
-               for (i = 0; i < drhd->devices_cnt; i++)
-                       if (drhd->devices[i] &&
-                           !IS_GFX_DEVICE(drhd->devices[i]))
+               for_each_active_dev_scope(drhd->devices,
+                                         drhd->devices_cnt, i, dev)
+                       if (!IS_GFX_DEVICE(dev))
                                break;
-
                if (i < drhd->devices_cnt)
                        continue;
 
@@ -3320,11 +3318,9 @@ static void __init init_no_remapping_devices(void)
                        intel_iommu_gfx_mapped = 1;
                } else {
                        drhd->ignored = 1;
-                       for (i = 0; i < drhd->devices_cnt; i++) {
-                               if (!drhd->devices[i])
-                                       continue;
-                               drhd->devices[i]->dev.archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
-                       }
+                       for_each_active_dev_scope(drhd->devices,
+                                                 drhd->devices_cnt, i, dev)
+                               dev->dev.archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
                }
        }
 }
@@ -3560,9 +3556,9 @@ static void intel_iommu_free_dmars(void)
 
 int dmar_find_matched_atsr_unit(struct pci_dev *dev)
 {
-       int i;
+       int i, ret = 1;
        struct pci_bus *bus;
-       struct pci_dev *bridge = NULL;
+       struct pci_dev *bridge = NULL, *tmp;
        struct acpi_dmar_atsr *atsr;
        struct dmar_atsr_unit *atsru;
 
@@ -3583,22 +3579,24 @@ int dmar_find_matched_atsr_unit(struct pci_dev *dev)
                if (atsr->segment != pci_domain_nr(dev->bus))
                        continue;
 
-               for (i = 0; i < atsru->devices_cnt; i++)
-                       if (atsru->devices[i] == bridge)
-                               return 1;
+               for_each_dev_scope(atsru->devices, atsru->devices_cnt, i, tmp)
+                       if (tmp == bridge)
+                               goto out;
 
                if (atsru->include_all)
-                       return 1;
+                       goto out;
        }
+       ret = 0;
+out:
 
-       return 0;
+       return ret;
 }
 
 int __init dmar_parse_rmrr_atsr_dev(void)
 {
        struct dmar_rmrr_unit *rmrr;
        struct dmar_atsr_unit *atsr;
-       int ret = 0;
+       int ret;
 
        list_for_each_entry(rmrr, &dmar_rmrr_units, list) {
                ret = rmrr_parse_dev(rmrr);
@@ -3612,7 +3610,7 @@ int __init dmar_parse_rmrr_atsr_dev(void)
                        return ret;
        }
 
-       return ret;
+       return 0;
 }
 
 /*

diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index ea599d4ca9e03bcc2224a701ee408aeebb48ccd0..4b77fd8fde7643fdc21cf8561ba42b22feae5d30 100644 (file)
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -65,6 +65,12 @@ extern struct list_head dmar_drhd_units;
        list_for_each_entry(drhd, &dmar_drhd_units, list)               \
                if (i=drhd->iommu, 0) {} else 
 
+#define        for_each_dev_scope(a, c, p, d)  \
+       for ((p) = 0; ((d) = (p) < (c) ? (a)[(p)] : NULL, (p) < (c)); (p)++)
+
+#define        for_each_active_dev_scope(a, c, p, d)   \
+       for_each_dev_scope((a), (c), (p), (d))  if (!(d)) { continue; } else
+
 extern int dmar_table_init(void);
 extern int dmar_dev_scope_init(void);
 extern int dmar_parse_dev_scope(void *start, void *end, int *cnt,