[tip: irq/msi] PCI/MSI: Allocate MSI device data on first use

tip-bot2 for Thomas Gleixner
2021-12-16T21:42:50Z

The following commit has been merged into the irq/msi branch of tip:

Commit-ID: 93296cd1325d1d9afede60202d8833011c9001f2
Gitweb: https://git.kernel.org/tip/93296cd1325d1d9afede60202d8833011c9001f2
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Wed, 15 Dec 2021 18:19:49 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Thu, 16 Dec 2021 22:16:38 +01:00

PCI/MSI: Allocate MSI device data on first use

Allocate MSI device data on first use, i.e. when a PCI driver invokes one
of the PCI/MSI enablement functions.

Add a wrapper function to ensure that the ordering vs. pcim_msi_release()
is correct.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/87r1adrdje.ffs@tglx

---
drivers/pci/msi/msi.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index 358b63e..369e3c5 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -366,6 +366,19 @@ static int pcim_setup_msi_release(struct pci_dev *dev)
return ret;
}

+/*
+ * Ordering vs. devres: msi device data has to be installed first so that
+ * pcim_msi_release() is invoked before it on device release.
+ */
+static int pci_setup_msi_context(struct pci_dev *dev)
+{
+ int ret = msi_setup_device_data(&dev->dev);
+
+ if (!ret)
+ ret = pcim_setup_msi_release(dev);
+ return ret;
+}
+
static struct msi_desc *
msi_setup_entry(struct pci_dev *dev, int nvec, struct irq_affinity *affd)
{
@@ -909,7 +922,7 @@ static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
if (nvec > maxvec)
nvec = maxvec;

- rc = pcim_setup_msi_release(dev);
+ rc = pci_setup_msi_context(dev);
if (rc)
return rc;

@@ -956,7 +969,7 @@ static int __pci_enable_msix_range(struct pci_dev *dev,
if (WARN_ON_ONCE(dev->msix_enabled))
return -EINVAL;

- rc = pcim_setup_msi_release(dev);
+ rc = pci_setup_msi_context(dev);
if (rc)
return rc;