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path: root/drivers/pci/ats.c
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Diffstat (limited to 'drivers/pci/ats.c')
-rw-r--r--drivers/pci/ats.c131
1 files changed, 46 insertions, 85 deletions
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index a8099d4d0c9d..eeb9fb2b47aa 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -17,34 +17,15 @@
#include "pci.h"
-static int ats_alloc_one(struct pci_dev *dev, int ps)
+void pci_ats_init(struct pci_dev *dev)
{
int pos;
- u16 cap;
- struct pci_ats *ats;
pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS);
if (!pos)
- return -ENODEV;
-
- ats = kzalloc(sizeof(*ats), GFP_KERNEL);
- if (!ats)
- return -ENOMEM;
-
- ats->pos = pos;
- ats->stu = ps;
- pci_read_config_word(dev, pos + PCI_ATS_CAP, &cap);
- ats->qdep = PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) :
- PCI_ATS_MAX_QDEP;
- dev->ats = ats;
-
- return 0;
-}
+ return;
-static void ats_free_one(struct pci_dev *dev)
-{
- kfree(dev->ats);
- dev->ats = NULL;
+ dev->ats_cap = pos;
}
/**
@@ -56,43 +37,36 @@ static void ats_free_one(struct pci_dev *dev)
*/
int pci_enable_ats(struct pci_dev *dev, int ps)
{
- int rc;
u16 ctrl;
+ struct pci_dev *pdev;
- BUG_ON(dev->ats && dev->ats->is_enabled);
-
- if (ps < PCI_ATS_MIN_STU)
+ if (!dev->ats_cap)
return -EINVAL;
- if (dev->is_physfn || dev->is_virtfn) {
- struct pci_dev *pdev = dev->is_physfn ? dev : dev->physfn;
-
- mutex_lock(&pdev->sriov->lock);
- if (pdev->ats)
- rc = pdev->ats->stu == ps ? 0 : -EINVAL;
- else
- rc = ats_alloc_one(pdev, ps);
-
- if (!rc)
- pdev->ats->ref_cnt++;
- mutex_unlock(&pdev->sriov->lock);
- if (rc)
- return rc;
- }
+ if (WARN_ON(dev->ats_enabled))
+ return -EBUSY;
- if (!dev->is_physfn) {
- rc = ats_alloc_one(dev, ps);
- if (rc)
- return rc;
- }
+ if (ps < PCI_ATS_MIN_STU)
+ return -EINVAL;
+ /*
+ * Note that enabling ATS on a VF fails unless it's already enabled
+ * with the same STU on the PF.
+ */
ctrl = PCI_ATS_CTRL_ENABLE;
- if (!dev->is_virtfn)
- ctrl |= PCI_ATS_CTRL_STU(ps - PCI_ATS_MIN_STU);
- pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl);
-
- dev->ats->is_enabled = 1;
+ if (dev->is_virtfn) {
+ pdev = pci_physfn(dev);
+ if (pdev->ats_stu != ps)
+ return -EINVAL;
+
+ atomic_inc(&pdev->ats_ref_cnt); /* count enabled VFs */
+ } else {
+ dev->ats_stu = ps;
+ ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
+ }
+ pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
+ dev->ats_enabled = 1;
return 0;
}
EXPORT_SYMBOL_GPL(pci_enable_ats);
@@ -103,28 +77,25 @@ EXPORT_SYMBOL_GPL(pci_enable_ats);
*/
void pci_disable_ats(struct pci_dev *dev)
{
+ struct pci_dev *pdev;
u16 ctrl;
- BUG_ON(!dev->ats || !dev->ats->is_enabled);
-
- pci_read_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, &ctrl);
- ctrl &= ~PCI_ATS_CTRL_ENABLE;
- pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl);
-
- dev->ats->is_enabled = 0;
+ if (WARN_ON(!dev->ats_enabled))
+ return;
- if (dev->is_physfn || dev->is_virtfn) {
- struct pci_dev *pdev = dev->is_physfn ? dev : dev->physfn;
+ if (atomic_read(&dev->ats_ref_cnt))
+ return; /* VFs still enabled */
- mutex_lock(&pdev->sriov->lock);
- pdev->ats->ref_cnt--;
- if (!pdev->ats->ref_cnt)
- ats_free_one(pdev);
- mutex_unlock(&pdev->sriov->lock);
+ if (dev->is_virtfn) {
+ pdev = pci_physfn(dev);
+ atomic_dec(&pdev->ats_ref_cnt);
}
- if (!dev->is_physfn)
- ats_free_one(dev);
+ pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, &ctrl);
+ ctrl &= ~PCI_ATS_CTRL_ENABLE;
+ pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
+
+ dev->ats_enabled = 0;
}
EXPORT_SYMBOL_GPL(pci_disable_ats);
@@ -132,16 +103,13 @@ void pci_restore_ats_state(struct pci_dev *dev)
{
u16 ctrl;
- if (!pci_ats_enabled(dev))
+ if (!dev->ats_enabled)
return;
- if (!pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS))
- BUG();
ctrl = PCI_ATS_CTRL_ENABLE;
if (!dev->is_virtfn)
- ctrl |= PCI_ATS_CTRL_STU(dev->ats->stu - PCI_ATS_MIN_STU);
-
- pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl);
+ ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
+ pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
}
EXPORT_SYMBOL_GPL(pci_restore_ats_state);
@@ -159,23 +127,16 @@ EXPORT_SYMBOL_GPL(pci_restore_ats_state);
*/
int pci_ats_queue_depth(struct pci_dev *dev)
{
- int pos;
u16 cap;
+ if (!dev->ats_cap)
+ return -EINVAL;
+
if (dev->is_virtfn)
return 0;
- if (dev->ats)
- return dev->ats->qdep;
-
- pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS);
- if (!pos)
- return -ENODEV;
-
- pci_read_config_word(dev, pos + PCI_ATS_CAP, &cap);
-
- return PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) :
- PCI_ATS_MAX_QDEP;
+ pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CAP, &cap);
+ return PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) : PCI_ATS_MAX_QDEP;
}
EXPORT_SYMBOL_GPL(pci_ats_queue_depth);