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| author | Thomas Gleixner <tglx@linutronix.de> | 2021-07-29 23:51:55 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2021-08-10 11:03:30 +0200 |
| commit | b296ababcc4bbf8efbb603d3aec6024a78662c1b (patch) | |
| tree | 6d0cecd40f0589c92f381d7940ddccb0dfb5162e /drivers/pci | |
| parent | 8eb5ce3f78a5e5d3f1a12248f6b7dc64ebf71da6 (diff) | |
| download | lwn-b296ababcc4bbf8efbb603d3aec6024a78662c1b.tar.gz lwn-b296ababcc4bbf8efbb603d3aec6024a78662c1b.zip | |
PCI/MSI: Deobfuscate virtual MSI-X
Handling of virtual MSI-X is obfuscated by letting pci_msix_desc_addr()
return NULL and checking the pointer.
Just use msi_desc::msi_attrib.is_virtual at the call sites and get rid of
that pointer check.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210729222543.151522318@linutronix.de
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/msi.c | 25 |
1 files changed, 8 insertions, 17 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index d2821bbbda60..1bde9eca8a78 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -166,11 +166,7 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) static void __iomem *pci_msix_desc_addr(struct msi_desc *desc) { - if (desc->msi_attrib.is_virtual) - return NULL; - - return desc->mask_base + - desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE; + return desc->mask_base + desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE; } /* @@ -182,14 +178,10 @@ static void __iomem *pci_msix_desc_addr(struct msi_desc *desc) */ static u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag) { + void __iomem *desc_addr = pci_msix_desc_addr(desc); u32 ctrl = desc->msix_ctrl; - void __iomem *desc_addr; - - if (pci_msi_ignore_mask) - return 0; - desc_addr = pci_msix_desc_addr(desc); - if (!desc_addr) + if (pci_msi_ignore_mask || desc->msi_attrib.is_virtual) return 0; ctrl &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT; @@ -256,10 +248,8 @@ void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg) if (entry->msi_attrib.is_msix) { void __iomem *base = pci_msix_desc_addr(entry); - if (!base) { - WARN_ON(1); + if (WARN_ON_ONCE(entry->msi_attrib.is_virtual)) return; - } msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR); msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR); @@ -292,7 +282,7 @@ void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg) void __iomem *base = pci_msix_desc_addr(entry); bool unmasked = !(entry->msix_ctrl & PCI_MSIX_ENTRY_CTRL_MASKBIT); - if (!base) + if (entry->msi_attrib.is_virtual) goto skip; /* @@ -744,9 +734,10 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, entry->msi_attrib.default_irq = dev->irq; entry->mask_base = base; - addr = pci_msix_desc_addr(entry); - if (addr) + if (!entry->msi_attrib.is_virtual) { + addr = pci_msix_desc_addr(entry); entry->msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL); + } list_add_tail(&entry->list, dev_to_msi_list(&dev->dev)); if (masks) |