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

[Thomas Gleixner <tglx@xxxxxxxxxxxxx>]

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

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
 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