From 3ac020e0ca8beff9b695f9866a06d50c09c602d6 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 12 Jul 2016 18:20:16 +0900 Subject: [PATCH] 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 Signed-off-by: Bjorn Helgaas Reviewed-by: Alexander Gordeev --- drivers/pci/msi.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index a385f39be6f7..98ace67c5f4d 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -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); -- 2.39.2