PCI: Make the "entries" argument to pci_enable_msix() optional

The "entries" argument isn't needed if the list of entries does not contain
any holes.  Make it optional so that we can avoid the need to allocate a
msix_entry structure for this (common) case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alexander Gordeev <agordeev@redhat.com>
This commit is contained in:
Christoph Hellwig 2016-07-12 18:20:16 +09:00 committed by Bjorn Helgaas
parent 12eb21de1f
commit 3ac020e0ca

View file

@ -695,7 +695,10 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
entry->msi_attrib.is_msix = 1;
entry->msi_attrib.is_64 = 1;
entry->msi_attrib.entry_nr = entries[i].entry;
if (entries)
entry->msi_attrib.entry_nr = entries[i].entry;
else
entry->msi_attrib.entry_nr = i;
entry->msi_attrib.default_irq = dev->irq;
entry->mask_base = base;
entry->nvec_used = 1;
@ -713,11 +716,11 @@ static void msix_program_entries(struct pci_dev *dev,
int i = 0;
for_each_pci_msi_entry(entry, dev) {
entries[i].vector = entry->irq;
if (entries)
entries[i++].vector = entry->irq;
entry->masked = readl(pci_msix_desc_addr(entry) +
PCI_MSIX_ENTRY_VECTOR_CTRL);
msix_mask_irq(entry, 1);
i++;
}
}
@ -930,7 +933,7 @@ EXPORT_SYMBOL(pci_msix_vec_count);
/**
* pci_enable_msix - configure device's MSI-X capability structure
* @dev: pointer to the pci_dev data structure of MSI-X device function
* @entries: pointer to an array of MSI-X entries
* @entries: pointer to an array of MSI-X entries (optional)
* @nvec: number of MSI-X irqs requested for allocation by device driver
*
* Setup the MSI-X capability structure of device function with the number
@ -950,22 +953,21 @@ int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
if (!pci_msi_supported(dev, nvec))
return -EINVAL;
if (!entries)
return -EINVAL;
nr_entries = pci_msix_vec_count(dev);
if (nr_entries < 0)
return nr_entries;
if (nvec > nr_entries)
return nr_entries;
/* Check for any invalid entries */
for (i = 0; i < nvec; i++) {
if (entries[i].entry >= nr_entries)
return -EINVAL; /* invalid entry */
for (j = i + 1; j < nvec; j++) {
if (entries[i].entry == entries[j].entry)
return -EINVAL; /* duplicate entry */
if (entries) {
/* Check for any invalid entries */
for (i = 0; i < nvec; i++) {
if (entries[i].entry >= nr_entries)
return -EINVAL; /* invalid entry */
for (j = i + 1; j < nvec; j++) {
if (entries[i].entry == entries[j].entry)
return -EINVAL; /* duplicate entry */
}
}
}
WARN_ON(!!dev->msix_enabled);