[PATCH 3/6] PCI MSI: msi_desc->dev is always initialised

Matthew Wilcox
2009-02-23T18:00:43Z

From: Matthew Wilcox <willy@linux.intel.com>

By passing the pci_dev into alloc_msi_entry() we can be sure that
the ->dev entry is always assigned and so we don't need to check it.
Also, we used kzalloc() so we don't need to initialise ->irq to 0.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
---
drivers/pci/msi.c | 29 ++++++++++++-----------------
1 files changed, 12 insertions(+), 17 deletions(-)

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index b3db438..a658c0f 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -110,7 +110,7 @@ static void msix_flush_writes(struct irq_desc *desc)
struct msi_desc *entry;

entry = get_irq_desc_msi(desc);
- BUG_ON(!entry || !entry->dev);
+ BUG_ON(!entry);
if (entry->msi_attrib.is_msix) {
int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET;
@@ -132,7 +132,7 @@ static int msi_set_mask_bits(struct irq_desc *desc, u32 mask, u32 flag)
struct msi_desc *entry;

entry = get_irq_desc_msi(desc);
- BUG_ON(!entry || !entry->dev);
+ BUG_ON(!entry);
if (entry->msi_attrib.is_msix) {
int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET;
@@ -248,19 +248,16 @@ void unmask_msi_irq(unsigned int irq)

static int msi_free_irqs(struct pci_dev* dev);

-static struct msi_desc* alloc_msi_entry(void)
+static struct msi_desc *alloc_msi_entry(struct pci_dev *dev)
{
- struct msi_desc *entry;
-
- entry = kzalloc(sizeof(struct msi_desc), GFP_KERNEL);
- if (!entry)
+ struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+ if (!desc)
return NULL;

- INIT_LIST_HEAD(&entry->list);
- entry->irq = 0;
- entry->dev = NULL;
+ INIT_LIST_HEAD(&desc->list);
+ desc->dev = dev;

- return entry;
+ return desc;
}

static void pci_intx_for_msi(struct pci_dev *dev, int enable)
@@ -351,7 +348,7 @@ static int msi_capability_init(struct pci_dev *dev)
pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
pci_read_config_word(dev, msi_control_reg(pos), &control);
/* MSI Entry Initialization */
- entry = alloc_msi_entry();
+ entry = alloc_msi_entry(dev);
if (!entry)
return -ENOMEM;

@@ -362,7 +359,6 @@ static int msi_capability_init(struct pci_dev *dev)
entry->msi_attrib.masked = 1;
entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */
entry->msi_attrib.pos = pos;
- entry->dev = dev;
if (entry->msi_attrib.maskbit) {
unsigned int base, maskbits, temp;

@@ -432,7 +428,7 @@ static int msix_capability_init(struct pci_dev *dev,

/* MSI-X Table Initialization */
for (i = 0; i < nvec; i++) {
- entry = alloc_msi_entry();
+ entry = alloc_msi_entry(dev);
if (!entry)
break;

@@ -444,7 +440,6 @@ static int msix_capability_init(struct pci_dev *dev,
entry->msi_attrib.masked = 1;
entry->msi_attrib.default_irq = dev->irq;
entry->msi_attrib.pos = pos;
- entry->dev = dev;
entry->mask_base = base;

list_add_tail(&entry->list, &dev->msi_list);
@@ -581,7 +576,7 @@ void pci_msi_shutdown(struct pci_dev* dev)
struct irq_desc *desc = irq_to_desc(dev->irq);
msi_set_mask_bits(desc, mask, ~mask);
}
- if (!entry->dev || entry->msi_attrib.is_msix)
+ if (entry->msi_attrib.is_msix)
return;

/* Restore dev->irq to its default pin-assertion irq */
@@ -598,7 +593,7 @@ void pci_disable_msi(struct pci_dev* dev)
pci_msi_shutdown(dev);

entry = list_entry(dev->msi_list.next, struct msi_desc, list);
- if (!entry->dev || entry->msi_attrib.is_msix)
+ if (entry->msi_attrib.is_msix)
return;

msi_free_irqs(dev);
--
1.5.6.5