[PATCH V2 02/11] x86/hyperv: cosmetic changes in irqdomain.c for readability

Mukesh R
2026-05-01T00:42:12Z

Make cosmetic changes:
o Rename struct pci_dev *dev to *pdev since there are cases of
struct device *dev in the file and all over the kernel
o Rename hv_build_pci_dev_id to hv_build_devid_type_pci in anticipation
of building different types of device ids
o Fix checkpatch.pl issues with return and extraneous printk
o Replace spaces with tabs
o Rename struct hv_devid *xxx to struct hv_devid *hv_devid given code
paths involve many types of device ids
o Fix indentation in a large if block by using goto.

There are no functional changes.

Reviewed-by: Anirudh Rayabharam (Microsoft) <anirudh@anirudhrb.com>
Signed-off-by: Mukesh R <mrathor@linux.microsoft.com>
---
arch/x86/hyperv/irqdomain.c | 198 +++++++++++++++++++-----------------
1 file changed, 104 insertions(+), 94 deletions(-)

diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c
index 365e364268d9..b3ad50a874dc 100644
--- a/arch/x86/hyperv/irqdomain.c
+++ b/arch/x86/hyperv/irqdomain.c
@@ -1,5 +1,4 @@
// SPDX-License-Identifier: GPL-2.0
-
/*
* Irqdomain for Linux to run as the root partition on Microsoft Hypervisor.
*
@@ -14,8 +13,8 @@
#include <linux/irqchip/irq-msi-lib.h>
#include <asm/mshyperv.h>

-static int hv_map_interrupt(union hv_device_id device_id, bool level,
- int cpu, int vector, struct hv_interrupt_entry *entry)
+static int hv_map_interrupt(union hv_device_id hv_devid, bool level,
+ int cpu, int vector, struct hv_interrupt_entry *ret_entry)
{
struct hv_input_map_device_interrupt *input;
struct hv_output_map_device_interrupt *output;
@@ -32,7 +31,7 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level,
intr_desc = &input->interrupt_descriptor;
memset(input, 0, sizeof(*input));
input->partition_id = hv_current_partition_id;
- input->device_id = device_id.as_uint64;
+ input->device_id = hv_devid.as_uint64;
intr_desc->interrupt_type = HV_X64_INTERRUPT_TYPE_FIXED;
intr_desc->vector_count = 1;
intr_desc->target.vector = vector;
@@ -44,7 +43,7 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level,

intr_desc->target.vp_set.valid_bank_mask = 0;
intr_desc->target.vp_set.format = HV_GENERIC_SET_SPARSE_4K;
- nr_bank = cpumask_to_vpset(&(intr_desc->target.vp_set), cpumask_of(cpu));
+ nr_bank = cpumask_to_vpset(&intr_desc->target.vp_set, cpumask_of(cpu));
if (nr_bank < 0) {
local_irq_restore(flags);
pr_err("%s: unable to generate VP set\n", __func__);
@@ -61,7 +60,7 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level,

status = hv_do_rep_hypercall(HVCALL_MAP_DEVICE_INTERRUPT, 0, var_size,
input, output);
- *entry = output->interrupt_entry;
+ *ret_entry = output->interrupt_entry;

local_irq_restore(flags);

@@ -71,21 +70,19 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level,
return hv_result_to_errno(status);
}

-static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *old_entry)
+static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *irq_entry)
{
unsigned long flags;
struct hv_input_unmap_device_interrupt *input;
- struct hv_interrupt_entry *intr_entry;
u64 status;

local_irq_save(flags);
input = *this_cpu_ptr(hyperv_pcpu_input_arg);

memset(input, 0, sizeof(*input));
- intr_entry = &input->interrupt_entry;
input->partition_id = hv_current_partition_id;
input->device_id = id;
- *intr_entry = *old_entry;
+ input->interrupt_entry = *irq_entry;

status = hv_do_hypercall(HVCALL_UNMAP_DEVICE_INTERRUPT, input, NULL);
local_irq_restore(flags);
@@ -115,67 +112,71 @@ static int get_rid_cb(struct pci_dev *pdev, u16 alias, void *data)
return 0;
}

-static union hv_device_id hv_build_pci_dev_id(struct pci_dev *dev)
+static union hv_device_id hv_build_devid_type_pci(struct pci_dev *pdev)
{
- union hv_device_id dev_id;
+ int pos;
+ union hv_device_id hv_devid;
struct rid_data data = {
.bridge = NULL,
- .rid = PCI_DEVID(dev->bus->number, dev->devfn)
+ .rid = PCI_DEVID(pdev->bus->number, pdev->devfn)
};

- pci_for_each_dma_alias(dev, get_rid_cb, &data);
+ pci_for_each_dma_alias(pdev, get_rid_cb, &data);

- dev_id.as_uint64 = 0;
- dev_id.device_type = HV_DEVICE_TYPE_PCI;
- dev_id.pci.segment = pci_domain_nr(dev->bus);
+ hv_devid.as_uint64 = 0;
+ hv_devid.device_type = HV_DEVICE_TYPE_PCI;
+ hv_devid.pci.segment = pci_domain_nr(pdev->bus);

- dev_id.pci.bdf.bus = PCI_BUS_NUM(data.rid);
- dev_id.pci.bdf.device = PCI_SLOT(data.rid);
- dev_id.pci.bdf.function = PCI_FUNC(data.rid);
- dev_id.pci.source_shadow = HV_SOURCE_SHADOW_NONE;
+ hv_devid.pci.bdf.bus = PCI_BUS_NUM(data.rid);
+ hv_devid.pci.bdf.device = PCI_SLOT(data.rid);
+ hv_devid.pci.bdf.function = PCI_FUNC(data.rid);
+ hv_devid.pci.source_shadow = HV_SOURCE_SHADOW_NONE;

- if (data.bridge) {
- int pos;
+ if (data.bridge == NULL)
+ goto out;

- /*
- * Microsoft Hypervisor requires a bus range when the bridge is
- * running in PCI-X mode.
- *
- * To distinguish conventional vs PCI-X bridge, we can check
- * the bridge's PCI-X Secondary Status Register, Secondary Bus
- * Mode and Frequency bits. See PCI Express to PCI/PCI-X Bridge
- * Specification Revision 1.0 5.2.2.1.3.
- *
- * Value zero means it is in conventional mode, otherwise it is
- * in PCI-X mode.
- */
+ /*
+ * Microsoft Hypervisor requires a bus range when the bridge is
+ * running in PCI-X mode.
+ *
+ * To distinguish conventional vs PCI-X bridge, we can check
+ * the bridge's PCI-X Secondary Status Register, Secondary Bus
+ * Mode and Frequency bits. See PCI Express to PCI/PCI-X Bridge
+ * Specification Revision 1.0 5.2.2.1.3.
+ *
+ * Value zero means it is in conventional mode, otherwise it is
+ * in PCI-X mode.
+ */

- pos = pci_find_capability(data.bridge, PCI_CAP_ID_PCIX);
- if (pos) {
- u16 status;
+ pos = pci_find_capability(data.bridge, PCI_CAP_ID_PCIX);
+ if (pos) {
+ u16 status;

- pci_read_config_word(data.bridge, pos +
- PCI_X_BRIDGE_SSTATUS, &status);
+ pci_read_config_word(data.bridge, pos + PCI_X_BRIDGE_SSTATUS,
+ &status);

- if (status & PCI_X_SSTATUS_FREQ) {
- /* Non-zero, PCI-X mode */
- u8 sec_bus, sub_bus;
+ if (status & PCI_X_SSTATUS_FREQ) {
+ /* Non-zero, PCI-X mode */
+ u8 sec_bus, sub_bus;

- dev_id.pci.source_shadow = HV_SOURCE_SHADOW_BRIDGE_BUS_RANGE;
+ hv_devid.pci.source_shadow =
+ HV_SOURCE_SHADOW_BRIDGE_BUS_RANGE;

- pci_read_config_byte(data.bridge, PCI_SECONDARY_BUS, &sec_bus);
- dev_id.pci.shadow_bus_range.secondary_bus = sec_bus;
- pci_read_config_byte(data.bridge, PCI_SUBORDINATE_BUS, &sub_bus);
- dev_id.pci.shadow_bus_range.subordinate_bus = sub_bus;
- }
+ pci_read_config_byte(data.bridge, PCI_SECONDARY_BUS,
+ &sec_bus);
+ hv_devid.pci.shadow_bus_range.secondary_bus = sec_bus;
+ pci_read_config_byte(data.bridge, PCI_SUBORDINATE_BUS,
+ &sub_bus);
+ hv_devid.pci.shadow_bus_range.subordinate_bus = sub_bus;
}
}

- return dev_id;
+out:
+ return hv_devid;
}

-/**
- * hv_map_msi_interrupt() - "Map" the MSI IRQ in the hypervisor.
+/*
+ * hv_map_msi_interrupt() - Map the MSI IRQ in the hypervisor.
* @data: Describes the IRQ
* @out_entry: Hypervisor (MSI) interrupt entry (can be NULL)
*
@@ -188,22 +189,23 @@ int hv_map_msi_interrupt(struct irq_data *data,
{
struct irq_cfg *cfg = irqd_cfg(data);
struct hv_interrupt_entry dummy;
- union hv_device_id device_id;
+ union hv_device_id hv_devid;
struct msi_desc *msidesc;
- struct pci_dev *dev;
+ struct pci_dev *pdev;
int cpu;

msidesc = irq_data_get_msi_desc(data);
- dev = msi_desc_to_pci_dev(msidesc);
- device_id = hv_build_pci_dev_id(dev);
+ pdev = msi_desc_to_pci_dev(msidesc);
+ hv_devid = hv_build_devid_type_pci(pdev);
cpu = cpumask_first(irq_data_get_effective_affinity_mask(data));

- return hv_map_interrupt(device_id, false, cpu, cfg->vector,
+ return hv_map_interrupt(hv_devid, false, cpu, cfg->vector,
out_entry ? out_entry : &dummy);
}
EXPORT_SYMBOL_GPL(hv_map_msi_interrupt);

-static inline void entry_to_msi_msg(struct hv_interrupt_entry *entry, struct msi_msg *msg)
+static void entry_to_msi_msg(struct hv_interrupt_entry *entry,
+ struct msi_msg *msg)
{
/* High address is always 0 */
msg->address_hi = 0;
@@ -211,17 +213,19 @@ static inline void entry_to_msi_msg(struct hv_interrupt_entry *entry, struct msi
msg->data = entry->msi_entry.data.as_uint32;
}

-static int hv_unmap_msi_interrupt(struct pci_dev *dev, struct hv_interrupt_entry *old_entry);
+static int hv_unmap_msi_interrupt(struct pci_dev *pdev,
+ struct hv_interrupt_entry *irq_entry);
+
static void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
{
struct hv_interrupt_entry *stored_entry;
struct irq_cfg *cfg = irqd_cfg(data);
struct msi_desc *msidesc;
- struct pci_dev *dev;
+ struct pci_dev *pdev;
int ret;

msidesc = irq_data_get_msi_desc(data);
- dev = msi_desc_to_pci_dev(msidesc);
+ pdev = msi_desc_to_pci_dev(msidesc);

if (!cfg) {
pr_debug("%s: cfg is NULL", __func__);
@@ -240,7 +244,7 @@ static void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
stored_entry = data->chip_data;
data->chip_data = NULL;

- ret = hv_unmap_msi_interrupt(dev, stored_entry);
+ ret = hv_unmap_msi_interrupt(pdev, stored_entry);

kfree(stored_entry);

@@ -249,10 +253,8 @@ static void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
}

stored_entry = kzalloc_obj(*stored_entry, GFP_ATOMIC);
- if (!stored_entry) {
- pr_debug("%s: failed to allocate chip data\n", __func__);
+ if (!stored_entry)
return;
- }

ret = hv_map_msi_interrupt(data, stored_entry);
if (ret) {
@@ -262,18 +264,21 @@ static void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)

data->chip_data = stored_entry;
entry_to_msi_msg(data->chip_data, msg);
-
- return;
}

-static int hv_unmap_msi_interrupt(struct pci_dev *dev, struct hv_interrupt_entry *old_entry)
+static int hv_unmap_msi_interrupt(struct pci_dev *pdev,
+ struct hv_interrupt_entry *irq_entry)
{
- return hv_unmap_interrupt(hv_build_pci_dev_id(dev).as_uint64, old_entry);
+ union hv_device_id hv_devid;
+
+ hv_devid = hv_build_devid_type_pci(pdev);
+ return hv_unmap_interrupt(hv_devid.as_uint64, irq_entry);
}

-static void hv_teardown_msi_irq(struct pci_dev *dev, struct irq_data *irqd)
+/* NB: during map, hv_interrupt_entry is saved via data->chip_data */
+static void hv_teardown_msi_irq(struct pci_dev *pdev, struct irq_data *irqd)
{
- struct hv_interrupt_entry old_entry;
+ struct hv_interrupt_entry irq_entry;
struct msi_msg msg;

if (!irqd->chip_data) {
@@ -281,13 +286,13 @@ static void hv_teardown_msi_irq(struct pci_dev *dev, struct irq_data *irqd)
return;
}

- old_entry = *(struct hv_interrupt_entry *)irqd->chip_data;
- entry_to_msi_msg(&old_entry, &msg);
+ irq_entry = *(struct hv_interrupt_entry *)irqd->chip_data;
+ entry_to_msi_msg(&irq_entry, &msg);

kfree(irqd->chip_data);
irqd->chip_data = NULL;

- (void)hv_unmap_msi_interrupt(dev, &old_entry);
+ (void)hv_unmap_msi_interrupt(pdev, &irq_entry);
}

/*
@@ -302,7 +307,8 @@ static struct irq_chip hv_pci_msi_controller = {
};

static bool hv_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
- struct irq_domain *real_parent, struct msi_domain_info *info)
+ struct irq_domain *real_parent,
+ struct msi_domain_info *info)
{
struct irq_chip *chip = info->chip;

@@ -317,7 +323,8 @@ static bool hv_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
}

#define HV_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK | MSI_FLAG_PCI_MSIX)
-#define HV_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS)
+#define HV_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS | \
+ MSI_FLAG_USE_DEF_CHIP_OPS)

static struct msi_parent_ops hv_msi_parent_ops = {
.supported_flags = HV_MSI_FLAGS_SUPPORTED,
@@ -329,14 +336,14 @@ static struct msi_parent_ops hv_msi_parent_ops = {
.init_dev_msi_info = hv_init_dev_msi_info,
};

-static int hv_msi_domain_alloc(struct irq_domain *d, unsigned int virq, unsigned int nr_irqs,
- void *arg)
+/* Allocate nr_irqs IRQs for the given irq domain */
+static int hv_msi_domain_alloc(struct irq_domain *d, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
{
/*
- * TODO: The allocation bits of hv_irq_compose_msi_msg(), i.e. everything except
- * entry_to_msi_msg() should be in here.
+ * TODO: The allocation bits of hv_irq_compose_msi_msg(), i.e.
+ * everything except entry_to_msi_msg() should be in here.
*/
-
int ret;

ret = irq_domain_alloc_irqs_parent(d, virq, nr_irqs, arg);
@@ -344,13 +351,15 @@ static int hv_msi_domain_alloc(struct irq_domain *d, unsigned int virq, unsigned
return ret;

for (int i = 0; i < nr_irqs; ++i) {
- irq_domain_set_info(d, virq + i, 0, &hv_pci_msi_controller, NULL,
- handle_edge_irq, NULL, "edge");
+ irq_domain_set_info(d, virq + i, 0, &hv_pci_msi_controller,
+ NULL, handle_edge_irq, NULL, "edge");
}
+
return 0;
}

-static void hv_msi_domain_free(struct irq_domain *d, unsigned int virq, unsigned int nr_irqs)
+static void hv_msi_domain_free(struct irq_domain *d, unsigned int virq,
+ unsigned int nr_irqs)
{
for (int i = 0; i < nr_irqs; ++i) {
struct irq_data *irqd = irq_domain_get_irq_data(d, virq);
@@ -362,6 +371,7 @@ static void hv_msi_domain_free(struct irq_domain *d, unsigned int virq, unsigned

hv_teardown_msi_irq(to_pci_dev(desc->dev), irqd);
}
+
irq_domain_free_irqs_top(d, virq, nr_irqs);
}

@@ -394,25 +404,25 @@ struct irq_domain * __init hv_create_pci_msi_domain(void)

int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *entry)
{
- union hv_device_id device_id;
+ union hv_device_id hv_devid;

- device_id.as_uint64 = 0;
- device_id.device_type = HV_DEVICE_TYPE_IOAPIC;
- device_id.ioapic.ioapic_id = (u8)ioapic_id;
+ hv_devid.as_uint64 = 0;
+ hv_devid.device_type = HV_DEVICE_TYPE_IOAPIC;
+ hv_devid.ioapic.ioapic_id = (u8)ioapic_id;

- return hv_unmap_interrupt(device_id.as_uint64, entry);
+ return hv_unmap_interrupt(hv_devid.as_uint64, entry);
}
EXPORT_SYMBOL_GPL(hv_unmap_ioapic_interrupt);

int hv_map_ioapic_interrupt(int ioapic_id, bool level, int cpu, int vector,
struct hv_interrupt_entry *entry)
{
- union hv_device_id device_id;
+ union hv_device_id hv_devid;

- device_id.as_uint64 = 0;
- device_id.device_type = HV_DEVICE_TYPE_IOAPIC;
- device_id.ioapic.ioapic_id = (u8)ioapic_id;
+ hv_devid.as_uint64 = 0;
+ hv_devid.device_type = HV_DEVICE_TYPE_IOAPIC;
+ hv_devid.ioapic.ioapic_id = (u8)ioapic_id;

- return hv_map_interrupt(device_id, level, cpu, vector, entry);
+ return hv_map_interrupt(hv_devid, level, cpu, vector, entry);
}
EXPORT_SYMBOL_GPL(hv_map_ioapic_interrupt);
--
2.51.2.vfs.0.1