[PATCH 22/34] x86/amd-iommu: Use get_device_id and check_device where appropriate

From: Joerg Roedel
Date: Fri Nov 27 2009 - 08:56:40 EST


The logic of these two functions is reimplemented (at least
in parts) in places in the code. This patch removes these
code duplications and uses the functions instead. As a side
effect it moves check_device() to the helper function code
section.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
arch/x86/kernel/amd_iommu.c | 110 +++++++++++++++++++------------------------
1 files changed, 49 insertions(+), 61 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 405f8da..d10195b 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -111,6 +111,33 @@ static struct dma_ops_domain *find_protection_domain(u16 devid)
return ret;
}

+/*
+ * This function checks if the driver got a valid device from the caller to
+ * avoid dereferencing invalid pointers.
+ */
+static bool check_device(struct device *dev)
+{
+ u16 devid;
+
+ if (!dev || !dev->dma_mask)
+ return false;
+
+ /* No device or no PCI device */
+ if (!dev || dev->bus != &pci_bus_type)
+ return false;
+
+ devid = get_device_id(dev);
+
+ /* Out of our scope? */
+ if (devid > amd_iommu_last_bdf)
+ return false;
+
+ if (amd_iommu_rlookup_table[devid] == NULL)
+ return false;
+
+ return true;
+}
+
#ifdef CONFIG_AMD_IOMMU_STATS

/*
@@ -1386,22 +1413,17 @@ static int device_change_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
- struct pci_dev *pdev = to_pci_dev(dev);
- u16 devid = calc_devid(pdev->bus->number, pdev->devfn);
+ u16 devid;
struct protection_domain *domain;
struct dma_ops_domain *dma_domain;
struct amd_iommu *iommu;
unsigned long flags;

- if (devid > amd_iommu_last_bdf)
- goto out;
-
- devid = amd_iommu_alias_table[devid];
-
- iommu = amd_iommu_rlookup_table[devid];
- if (iommu == NULL)
- goto out;
+ if (!check_device(dev))
+ return 0;

+ devid = get_device_id(dev);
+ iommu = amd_iommu_rlookup_table[devid];
domain = domain_for_device(dev);

if (domain && !dma_ops_domain(domain))
@@ -1453,36 +1475,6 @@ static struct notifier_block device_nb = {
*****************************************************************************/

/*
- * This function checks if the driver got a valid device from the caller to
- * avoid dereferencing invalid pointers.
- */
-static bool check_device(struct device *dev)
-{
- u16 bdf;
- struct pci_dev *pcidev;
-
- if (!dev || !dev->dma_mask)
- return false;
-
- /* No device or no PCI device */
- if (!dev || dev->bus != &pci_bus_type)
- return false;
-
- pcidev = to_pci_dev(dev);
-
- bdf = calc_devid(pcidev->bus->number, pcidev->devfn);
-
- /* Out of our scope? */
- if (bdf > amd_iommu_last_bdf)
- return false;
-
- if (amd_iommu_rlookup_table[bdf] == NULL)
- return false;
-
- return true;
-}
-
-/*
* In the dma_ops path we only have the struct device. This function
* finds the corresponding IOMMU, the protection domain and the
* requestor id for a given device.
@@ -2094,15 +2086,20 @@ static void prealloc_protection_domains(void)
struct pci_dev *dev = NULL;
struct dma_ops_domain *dma_dom;
struct amd_iommu *iommu;
- u16 devid, __devid;
+ u16 devid;

while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
- __devid = devid = calc_devid(dev->bus->number, dev->devfn);
- if (devid > amd_iommu_last_bdf)
+
+ /* Do we handle this device? */
+ if (!check_device(&dev->dev))
continue;
- devid = amd_iommu_alias_table[devid];
+
+ /* Is there already any domain for it? */
if (domain_for_device(&dev->dev))
continue;
+
+ devid = get_device_id(&dev->dev);
+
iommu = amd_iommu_rlookup_table[devid];
if (!iommu)
continue;
@@ -2294,17 +2291,14 @@ static void amd_iommu_detach_device(struct iommu_domain *dom,
struct device *dev)
{
struct amd_iommu *iommu;
- struct pci_dev *pdev;
u16 devid;

- if (dev->bus != &pci_bus_type)
+ if (!check_device(dev))
return;

- pdev = to_pci_dev(dev);
-
- devid = calc_devid(pdev->bus->number, pdev->devfn);
+ devid = get_device_id(dev);

- if (devid > 0)
+ if (amd_iommu_pd_table[devid] != NULL)
detach_device(dev);

iommu = amd_iommu_rlookup_table[devid];
@@ -2321,20 +2315,13 @@ static int amd_iommu_attach_device(struct iommu_domain *dom,
struct protection_domain *domain = dom->priv;
struct protection_domain *old_domain;
struct amd_iommu *iommu;
- struct pci_dev *pdev;
int ret;
u16 devid;

- if (dev->bus != &pci_bus_type)
+ if (!check_device(dev))
return -EINVAL;

- pdev = to_pci_dev(dev);
-
- devid = calc_devid(pdev->bus->number, pdev->devfn);
-
- if (devid >= amd_iommu_last_bdf ||
- devid != amd_iommu_alias_table[devid])
- return -EINVAL;
+ devid = get_device_id(dev);

iommu = amd_iommu_rlookup_table[devid];
if (!iommu)
@@ -2458,10 +2445,11 @@ int __init amd_iommu_init_passthrough(void)

while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {

- devid = calc_devid(dev->bus->number, dev->devfn);
- if (devid > amd_iommu_last_bdf)
+ if (!check_device(&dev->dev))
continue;

+ devid = get_device_id(&dev->dev);
+
iommu = amd_iommu_rlookup_table[devid];
if (!iommu)
continue;
--
1.6.5.3


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