MSI: Remove dev->first_msi_irq
Now that we keep a list of msi descriptors, we don't need first_msi_irq
in the pci dev.
If we somehow have zero MSIs configured list_entry() will give us weird
oopes or nice memory corruption bugs. So be paranoid. Add BUG_ONs and also
a check in pci_msi_check_device() to make sure nvec > 0.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 434c718..7a44ba4 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -269,7 +269,8 @@
msi_set_mask_bit(entry->irq, entry->msi_attrib.masked);
}
- entry = get_irq_msi(dev->first_msi_irq);
+ BUG_ON(list_empty(&dev->msi_list));
+ entry = list_entry(dev->msi_list.next, struct msi_desc, list);
pos = entry->msi_attrib.pos;
pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
control &= ~PCI_MSIX_FLAGS_MASKALL;
@@ -341,7 +342,6 @@
}
entry->irq = irq;
list_add(&entry->list, &dev->msi_list);
- dev->first_msi_irq = irq;
set_irq_msi(irq, entry);
/* Set MSI enabled bits */
@@ -433,7 +433,6 @@
avail = -EBUSY;
return avail;
}
- dev->first_msi_irq = entries[0].vector;
/* Set MSI-X enabled bits */
pci_intx(dev, 0); /* disable intx */
msix_set_enable(dev, 1);
@@ -461,6 +460,14 @@
if (!pci_msi_enable || !dev || dev->no_msi)
return -EINVAL;
+ /*
+ * You can't ask to have 0 or less MSIs configured.
+ * a) it's stupid ..
+ * b) the list manipulation code assumes nvec >= 1.
+ */
+ if (nvec < 1)
+ return -ERANGE;
+
/* Any bridge which does NOT route MSI transactions from it's
* secondary bus to it's primary bus must set NO_MSI flag on
* the secondary pci_bus.
@@ -525,18 +532,17 @@
pci_intx(dev, 1); /* enable intx */
dev->msi_enabled = 0;
- entry = get_irq_msi(dev->first_msi_irq);
- if (!entry || !entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI) {
+ BUG_ON(list_empty(&dev->msi_list));
+ entry = list_entry(dev->msi_list.next, struct msi_desc, list);
+ if (!entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI) {
return;
}
default_irq = entry->msi_attrib.default_irq;
- msi_free_irq(dev, dev->first_msi_irq);
+ msi_free_irq(dev, entry->irq);
/* Restore dev->irq to its default pin-assertion irq */
dev->irq = default_irq;
-
- dev->first_msi_irq = 0;
}
EXPORT_SYMBOL(pci_disable_msi);
@@ -634,7 +640,6 @@
list_for_each_entry(entry, &dev->msi_list, list)
msi_free_irq(dev, entry->irq);
- dev->first_msi_irq = 0;
}
void pci_disable_msix(struct pci_dev* dev)
@@ -664,8 +669,12 @@
if (!pci_msi_enable || !dev)
return;
- if (dev->msi_enabled)
- msi_free_irq(dev, dev->first_msi_irq);
+ if (dev->msi_enabled) {
+ struct msi_desc *entry;
+ BUG_ON(list_empty(&dev->msi_list));
+ entry = list_entry(dev->msi_list.next, struct msi_desc, list);
+ msi_free_irq(dev, entry->irq);
+ }
if (dev->msix_enabled)
msix_free_all_irqs(dev);