[patch 06/10] PCI/MSI: Use range in allocation path

Thomas Gleixner
2021-11-27T02:20:53Z

Make the allocation path range based to prepare for runtime expansion of
MSI-X vectors.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
drivers/pci/msi/irqdomain.c | 7 +++----
drivers/pci/msi/msi.c | 34 +++++++++++++++++++++-------------
drivers/pci/msi/msi.h | 2 +-
3 files changed, 25 insertions(+), 18 deletions(-)

--- a/drivers/pci/msi/irqdomain.c
+++ b/drivers/pci/msi/irqdomain.c
@@ -8,16 +8,15 @@

#include "msi.h"

-int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+int pci_msi_setup_msi_irqs(struct pci_dev *dev, struct msi_range *range, int type)
{
- struct msi_range range = { .first = 0, .last = UINT_MAX, .ndesc = nvec};
struct irq_domain *domain;

domain = dev_get_msi_domain(&dev->dev);
if (domain && irq_domain_is_hierarchy(domain))
- return msi_domain_alloc_irqs_descs_locked(domain, &dev->dev, &range);
+ return msi_domain_alloc_irqs_descs_locked(domain, &dev->dev, range);

- return pci_msi_legacy_setup_msi_irqs(dev, nvec, type);
+ return pci_msi_legacy_setup_msi_irqs(dev, range->ndesc, type);
}

void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -370,14 +370,16 @@ static int msi_setup_msi_desc(struct pci
return ret;
}

-static int msi_verify_entries(struct pci_dev *dev)
+static int msi_verify_entries(struct pci_dev *dev, struct msi_range *range)
{
struct msi_desc *entry;

if (!dev->no_64bit_msi)
return 0;

- msi_for_each_desc(entry, &dev->dev, MSI_DESC_ALL) {
+ msi_for_each_desc_from(entry, &dev->dev, MSI_DESC_ALL, range->first) {
+ if (entry->msi_index > range->last)
+ return 0;
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);
@@ -402,6 +404,7 @@ static int msi_verify_entries(struct pci
static int msi_capability_init(struct pci_dev *dev, int nvec,
struct irq_affinity *affd)
{
+ struct msi_range range = { .first = 0, .last = 0, .ndesc = nvec, };
struct irq_affinity_desc *masks = NULL;
struct msi_desc *entry;
int ret;
@@ -421,11 +424,11 @@ static int msi_capability_init(struct pc
pci_msi_mask(entry, msi_multi_mask(entry));

/* Configure MSI capability structure */
- ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
+ ret = pci_msi_setup_msi_irqs(dev, &range, PCI_CAP_ID_MSI);
if (ret)
goto err;

- ret = msi_verify_entries(dev);
+ ret = msi_verify_entries(dev, &range);
if (ret)
goto err;

@@ -469,7 +472,8 @@ static void __iomem *msix_map_region(str
}

static int msix_setup_msi_descs(struct pci_dev *dev, void __iomem *base,
- struct msix_entry *entries, int nvec,
+ struct msi_range *range,
+ struct msix_entry *entries,
struct irq_affinity_desc *masks)
{
int ret, i, vec_count = pci_msix_vec_count(dev);
@@ -485,8 +489,8 @@ static int msix_setup_msi_descs(struct p
desc.pci.msi_attrib.default_irq = dev->irq;
desc.pci.mask_base = base;

- for (i = 0, curmsk = masks; i < nvec; i++, curmsk++) {
- desc.msi_index = entries ? entries[i].entry : i;
+ for (i = 0, curmsk = masks; i < range->ndesc; i++, curmsk++) {
+ desc.msi_index = entries ? entries[i].entry : range->first + i;
desc.affinity = masks ? curmsk : NULL;
desc.pci.msi_attrib.is_virtual = desc.msi_index >= vec_count;
desc.pci.msi_attrib.can_mask = !pci_msi_ignore_mask &&
@@ -500,6 +504,9 @@ static int msix_setup_msi_descs(struct p
ret = msi_add_msi_desc(&dev->dev, &desc);
if (ret)
break;
+
+ if (desc.msi_index > range->last)
+ range->last = desc.msi_index;
}

return ret;
@@ -530,28 +537,28 @@ static void msix_mask_all(void __iomem *
}

static int msix_setup_interrupts(struct pci_dev *dev, void __iomem *base,
- struct msix_entry *entries, int nvec,
+ struct msi_range *range, struct msix_entry *entries,
struct irq_affinity *affd)
{
struct irq_affinity_desc *masks = NULL;
int ret;

if (affd)
- masks = irq_create_affinity_masks(nvec, affd);
+ masks = irq_create_affinity_masks(range->ndesc, affd);

msi_lock_descs(&dev->dev);
- ret = msix_setup_msi_descs(dev, base, entries, nvec, masks);
+ ret = msix_setup_msi_descs(dev, base, range, entries, masks);
if (ret)
goto out_free;

dev->dev.msi.data->properties = MSI_PROP_PCI_MSIX | MSI_PROP_64BIT;

- ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
+ ret = pci_msi_setup_msi_irqs(dev, range, PCI_CAP_ID_MSIX);
if (ret)
goto out_free;

/* Check if all MSI entries honor device restrictions */
- ret = msi_verify_entries(dev);
+ ret = msi_verify_entries(dev, range);
if (ret)
goto out_free;

@@ -580,6 +587,7 @@ static int msix_setup_interrupts(struct
static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
int nvec, struct irq_affinity *affd)
{
+ struct msi_range range = { .first = 0, .last = 0, .ndesc = nvec, };
void __iomem *base;
int ret, tsize;
u16 control;
@@ -606,7 +614,7 @@ static int msix_capability_init(struct p
/* Ensure that all table entries are masked. */
msix_mask_all(base, tsize);

- ret = msix_setup_interrupts(dev, base, entries, nvec, affd);
+ ret = msix_setup_interrupts(dev, base, &range, entries, affd);
if (ret)
goto out_disable;

--- a/drivers/pci/msi/msi.h
+++ b/drivers/pci/msi/msi.h
@@ -5,7 +5,7 @@

#define msix_table_size(flags) ((flags & PCI_MSIX_FLAGS_QSIZE) + 1)

-extern int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
+extern int pci_msi_setup_msi_irqs(struct pci_dev *dev, struct msi_range *range, int type);
extern void pci_msi_teardown_msi_irqs(struct pci_dev *dev);

#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS