Re: [patch V2 10/31] PCI/MSI: Use msi_on_each_desc()

Bjorn Helgaas
2021-12-07T21:07:54Z

On Mon, Dec 06, 2021 at 11:51:18PM +0100, Thomas Gleixner wrote:
> Use the new iterator functions which pave the way for dynamically extending
> MSI-X vectors.
>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>

> ---
> drivers/pci/msi/irqdomain.c | 4 ++--
> drivers/pci/msi/legacy.c | 19 ++++++++-----------
> drivers/pci/msi/msi.c | 30 ++++++++++++++----------------
> 3 files changed, 24 insertions(+), 29 deletions(-)
>
> --- a/drivers/pci/msi/irqdomain.c
> +++ b/drivers/pci/msi/irqdomain.c
> @@ -83,7 +83,7 @@ static int pci_msi_domain_check_cap(stru
> struct msi_domain_info *info,
> struct device *dev)
> {
> - struct msi_desc *desc = first_pci_msi_entry(to_pci_dev(dev));
> + struct msi_desc *desc = msi_first_desc(dev, MSI_DESC_ALL);
>
> /* Special handling to support __pci_enable_msi_range() */
> if (pci_msi_desc_is_multi_msi(desc) &&
> @@ -98,7 +98,7 @@ static int pci_msi_domain_check_cap(stru
> unsigned int idx = 0;
>
> /* Check for gaps in the entry indices */
> - for_each_msi_entry(desc, dev) {
> + msi_for_each_desc(desc, dev, MSI_DESC_ALL) {
> if (desc->msi_index != idx++)
> return -ENOTSUPP;
> }
> --- a/drivers/pci/msi/legacy.c
> +++ b/drivers/pci/msi/legacy.c
> @@ -28,7 +28,7 @@ int __weak arch_setup_msi_irqs(struct pc
> if (type == PCI_CAP_ID_MSI && nvec > 1)
> return 1;
>
> - for_each_pci_msi_entry(desc, dev) {
> + msi_for_each_desc(desc, &dev->dev, MSI_DESC_NOTASSOCIATED) {
> ret = arch_setup_msi_irq(dev, desc);
> if (ret)
> return ret < 0 ? ret : -ENOSPC;
> @@ -42,27 +42,24 @@ void __weak arch_teardown_msi_irqs(struc
> struct msi_desc *desc;
> int i;
>
> - for_each_pci_msi_entry(desc, dev) {
> - if (desc->irq) {
> - for (i = 0; i < desc->nvec_used; i++)
> - arch_teardown_msi_irq(desc->irq + i);
> - }
> + msi_for_each_desc(desc, &dev->dev, MSI_DESC_ASSOCIATED) {
> + for (i = 0; i < desc->nvec_used; i++)
> + arch_teardown_msi_irq(desc->irq + i);
> }
> }
>
> static int pci_msi_setup_check_result(struct pci_dev *dev, int type, int ret)
> {
> - struct msi_desc *entry;
> + struct msi_desc *desc;
> int avail = 0;
>
> if (type != PCI_CAP_ID_MSIX || ret >= 0)
> return ret;
>
> /* Scan the MSI descriptors for successfully allocated ones. */
> - for_each_pci_msi_entry(entry, dev) {
> - if (entry->irq != 0)
> - avail++;
> - }
> + msi_for_each_desc(desc, &dev->dev, MSI_DESC_ASSOCIATED)
> + avail++;
> +
> return avail ? avail : ret;
> }
>
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -299,7 +299,6 @@ static void __pci_restore_msix_state(str
>
> if (!dev->msix_enabled)
> return;
> - BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
>
> /* route the table */
> pci_intx_for_msi(dev, 0);
> @@ -309,7 +308,7 @@ static void __pci_restore_msix_state(str
> write_msg = arch_restore_msi_irqs(dev);
>
> msi_lock_descs(&dev->dev);
> - for_each_pci_msi_entry(entry, dev) {
> + msi_for_each_desc(entry, &dev->dev, MSI_DESC_ALL) {
> if (write_msg)
> __pci_write_msi_msg(entry, &entry->msg);
> pci_msix_write_vector_ctrl(entry, entry->pci.msix_ctrl);
> @@ -378,14 +377,14 @@ static int msi_verify_entries(struct pci
> if (!dev->no_64bit_msi)
> return 0;
>
> - for_each_pci_msi_entry(entry, dev) {
> + msi_for_each_desc(entry, &dev->dev, MSI_DESC_ALL) {
> if (entry->msg.address_hi) {
> pci_err(dev, "arch assigned 64-bit MSI address %#x%08x but device only supports 32 bits\n",
> entry->msg.address_hi, entry->msg.address_lo);
> - return -EIO;
> + break;
> }
> }
> - return 0;
> + return !entry ? 0 : -EIO;
> }
>
> /**
> @@ -418,7 +417,7 @@ static int msi_capability_init(struct pc
> goto unlock;
>
> /* All MSIs are unmasked by default; mask them all */
> - entry = first_pci_msi_entry(dev);
> + entry = msi_first_desc(&dev->dev, MSI_DESC_ALL);
> pci_msi_mask(entry, msi_multi_mask(entry));
>
> /* Configure MSI capability structure */
> @@ -508,11 +507,11 @@ static int msix_setup_msi_descs(struct p
>
> static void msix_update_entries(struct pci_dev *dev, struct msix_entry *entries)
> {
> - struct msi_desc *entry;
> + struct msi_desc *desc;
>
> if (entries) {
> - for_each_pci_msi_entry(entry, dev) {
> - entries->vector = entry->irq;
> + msi_for_each_desc(desc, &dev->dev, MSI_DESC_ALL) {
> + entries->vector = desc->irq;
> entries++;
> }
> }
> @@ -705,15 +704,14 @@ static void pci_msi_shutdown(struct pci_
> if (!pci_msi_enable || !dev || !dev->msi_enabled)
> return;
>
> - BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
> - desc = first_pci_msi_entry(dev);
> -
> pci_msi_set_enable(dev, 0);
> pci_intx_for_msi(dev, 1);
> dev->msi_enabled = 0;
>
> /* Return the device with MSI unmasked as initial states */
> - pci_msi_unmask(desc, msi_multi_mask(desc));
> + desc = msi_first_desc(&dev->dev, MSI_DESC_ALL);
> + if (!WARN_ON_ONCE(!desc))
> + pci_msi_unmask(desc, msi_multi_mask(desc));
>
> /* Restore dev->irq to its default pin-assertion IRQ */
> dev->irq = desc->pci.msi_attrib.default_irq;
> @@ -789,7 +787,7 @@ static int __pci_enable_msix(struct pci_
>
> static void pci_msix_shutdown(struct pci_dev *dev)
> {
> - struct msi_desc *entry;
> + struct msi_desc *desc;
>
> if (!pci_msi_enable || !dev || !dev->msix_enabled)
> return;
> @@ -800,8 +798,8 @@ static void pci_msix_shutdown(struct pci
> }
>
> /* Return the device with MSI-X masked as initial states */
> - for_each_pci_msi_entry(entry, dev)
> - pci_msix_mask(entry);
> + msi_for_each_desc(desc, &dev->dev, MSI_DESC_ALL)
> + pci_msix_mask(desc);
>
> pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
> pci_intx_for_msi(dev, 1);
>