core: Introduce PCI device iterator

We will have more of these iterations in the future, so let's make them
more handy to use.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

diff --git a/hypervisor/pci.c b/hypervisor/pci.c
index ee46adf7e8bd7ef5d8486085788bc945db6cbf60..c8b4991be6007aea4314b1fe74c4c406ba04f6c9 100644 (file)
--- a/hypervisor/pci.c
+++ b/hypervisor/pci.c
@@ -34,6 +34,11 @@ struct acpi_mcfg_table {
        struct acpi_mcfg_alloc alloc_structs[];
 } __attribute__((packed));
 
+#define for_each_configured_pci_device(dev, cell)                      \
+       for ((dev) = (cell)->pci_devices;                               \
+            (dev) - (cell)->pci_devices < (cell)->config->num_pci_devices; \
+            (dev)++)
+
 /* entry for PCI config space whitelist (granting access) */
 struct pci_cfg_access {
        u32 reg_num; /** Register number (4-byte aligned) */
@@ -377,10 +382,9 @@ int pci_cell_init(struct cell *cell)
 
 static void pci_return_device_to_root_cell(struct pci_device *device)
 {
-       struct pci_device *root_device = root_cell.pci_devices;
-       unsigned int n;
+       struct pci_device *root_device;
 
-       for (n = 0; n < root_cell.config->num_pci_devices; n++, root_device++)
+       for_each_configured_pci_device(root_device, &root_cell)
                if (root_device->info->domain == device->info->domain &&
                    root_device->info->bdf == device->info->bdf) {
                        if (pci_add_device(&root_cell, root_device) < 0)
@@ -396,7 +400,7 @@ void pci_cell_exit(struct cell *cell)
 {
        unsigned long array_size = PAGE_ALIGN(cell->config->num_pci_devices *
                                              sizeof(struct pci_device));
-       unsigned int n;
+       struct pci_device *device;
 
        /*
         * Do not destroy the root cell. We will shut down the complete
@@ -405,11 +409,11 @@ void pci_cell_exit(struct cell *cell)
        if (cell == &root_cell)
                return;
 
-       for (n = 0; n < cell->config->num_pci_devices; n++) {
-               if (!cell->pci_devices[n].cell)
+       for_each_configured_pci_device(device, cell) {
+               if (!device->cell)
                        continue;
-               pci_remove_device(&cell->pci_devices[n]);
-               pci_return_device_to_root_cell(&cell->pci_devices[n]);
+               pci_remove_device(device);
+               pci_return_device_to_root_cell(device);
        }
 
        page_free(&mem_pool, cell->pci_devices, array_size / PAGE_SIZE);