[PATCH v4 5/7] PCI: hv: Use hv_setup_*() to set up hypercall arguments

[mhkelley58@gmail.com]

From: Michael Kelley <mhklinux@outlook.com>

Update hypercall call sites to use the new hv_setup_*() functions
to set up hypercall arguments. Since these functions zero the
fixed portion of input memory, remove now redundant calls to memset().

Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
---

Notes:
    Changes in v4:
    * Rename hv_hvcall_*() functions to hv_setup_*() [Easwar Hariharan]
    * Rename hv_hvcall_in_batch_size() to hv_get_input_batch_size()
      [Easwar Hariharan]
    
    Changes in v3:
    * Removed change to definition of struct hv_mmio_write_input so it remains
      consistent with original Hyper-V definitions. Adjusted argument to
      hv_hvcall_in_array() accordingly so that the 64 byte 'data' array is
      not zero'ed. [Nuno Das Neves]
    
    Changes in v2:
    * In hv_arch_irq_unmask(), added check of the number of computed banks
      in the hv_vpset against the batch_size. Since an hv_vpset currently
      represents a maximum of 4096 CPUs, the hv_vpset size does not exceed
      512 bytes and there should always be sufficent space. But do the
      check just in case something changes. [Nuno Das Neves]

 drivers/pci/controller/pci-hyperv.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index d2b7e8ea710b..79de85d1d68b 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -620,7 +620,7 @@ static void hv_irq_retarget_interrupt(struct irq_data *data)
 	struct pci_dev *pdev;
 	unsigned long flags;
 	u32 var_size = 0;
-	int cpu, nr_bank;
+	int cpu, nr_bank, batch_size;
 	u64 res;
 
 	dest = irq_data_get_effective_affinity_mask(data);
@@ -636,8 +636,8 @@ static void hv_irq_retarget_interrupt(struct irq_data *data)
 
 	local_irq_save(flags);
 
-	params = *this_cpu_ptr(hyperv_pcpu_input_arg);
-	memset(params, 0, sizeof(*params));
+	batch_size = hv_setup_in_array(&params, sizeof(*params),
+					sizeof(params->int_target.vp_set.bank_contents[0]));
 	params->partition_id = HV_PARTITION_ID_SELF;
 	params->int_entry.source = HV_INTERRUPT_SOURCE_MSI;
 	params->int_entry.msi_entry.address.as_uint32 = int_desc->address & 0xffffffff;
@@ -669,7 +669,7 @@ static void hv_irq_retarget_interrupt(struct irq_data *data)
 		nr_bank = cpumask_to_vpset(&params->int_target.vp_set, tmp);
 		free_cpumask_var(tmp);
 
-		if (nr_bank <= 0) {
+		if (nr_bank <= 0 || nr_bank > batch_size) {
 			res = 1;
 			goto out;
 		}
@@ -1102,11 +1102,9 @@ static void hv_pci_read_mmio(struct device *dev, phys_addr_t gpa, int size, u32
 
 	/*
 	 * Must be called with interrupts disabled so it is safe
-	 * to use the per-cpu input argument page.  Use it for
-	 * both input and output.
+	 * to use the per-cpu argument page.
 	 */
-	in = *this_cpu_ptr(hyperv_pcpu_input_arg);
-	out = *this_cpu_ptr(hyperv_pcpu_input_arg) + sizeof(*in);
+	hv_setup_inout(&in, sizeof(*in), &out, sizeof(*out));
 	in->gpa = gpa;
 	in->size = size;
 
@@ -1135,9 +1133,9 @@ static void hv_pci_write_mmio(struct device *dev, phys_addr_t gpa, int size, u32
 
 	/*
 	 * Must be called with interrupts disabled so it is safe
-	 * to use the per-cpu input argument memory.
+	 * to use the per-cpu argument page.
 	 */
-	in = *this_cpu_ptr(hyperv_pcpu_input_arg);
+	hv_setup_in_array(&in, offsetof(typeof(*in), data), sizeof(in->data[0]));
 	in->gpa = gpa;
 	in->size = size;
 	switch (size) {
-- 
2.25.1