kvm tools: Introduce IRQ registry

Instead of having static definitions of devices, Use a
dynamic registry of pci devices.

The structure is a rbtree which holds device types (net,
blk, etc). Each device entry holds a list of IRQ lines
associated with that device (pin).

Devices dynamically register upon initialization, and receive
a set of: device id, irq pin and irq line.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/tools/kvm/Makefile b/tools/kvm/Makefile
index 89c7e3d5567dc4e2c4cbd017c779b907e4f27358..fb839fcb93f310d6882178c458679fabf7e2c921 100644 (file)
--- a/tools/kvm/Makefile
+++ b/tools/kvm/Makefile
@@ -39,6 +39,8 @@ OBJS    += kvm-run.o
 OBJS    += qcow.o
 OBJS    += mptable.o
 OBJS    += threadpool.o
+OBJS    += irq.o
+OBJS    += ../../lib/rbtree.o
 
 DEPS   := $(patsubst %.o,%.d,$(OBJS))
 

diff --git a/tools/kvm/include/kvm/irq.h b/tools/kvm/include/kvm/irq.h
new file mode 100644 (file)
index 0000000..7a75a0c
--- /dev/null
+++ b/tools/kvm/include/kvm/irq.h
@@ -0,0 +1,24 @@
+#ifndef KVM__IRQ_H
+#define KVM__IRQ_H
+
+#include <linux/types.h>
+#include <linux/rbtree.h>
+#include <linux/list.h>
+
+struct irq_line {
+       u8                      line;
+       struct list_head        node;
+};
+
+struct pci_dev {
+       struct rb_node          node;
+       u32                     id;
+       u8                      pin;
+       struct list_head        lines;
+};
+
+int irq__register_device(u32 dev, u8 *num, u8 *pin, u8 *line);
+
+struct rb_node *irq__get_pci_tree(void);
+
+#endif

diff --git a/tools/kvm/include/linux/module.h b/tools/kvm/include/linux/module.h
new file mode 100644 (file)
index 0000000..0e4c6a3
--- /dev/null
+++ b/tools/kvm/include/linux/module.h
@@ -0,0 +1,6 @@
+#ifndef KVM__LINUX_MODULE_H
+#define KVM__LINUX_MODULE_H
+
+#define EXPORT_SYMBOL(name)
+
+#endif

diff --git a/tools/kvm/irq.c b/tools/kvm/irq.c
new file mode 100644 (file)
index 0000000..4f4305f
--- /dev/null
+++ b/tools/kvm/irq.c
@@ -0,0 +1,107 @@
+#include "kvm/irq.h"
+
+#include <linux/types.h>
+#include <linux/rbtree.h>
+#include <linux/list.h>
+
+#include <stddef.h>
+#include <stdlib.h>
+
+static u8              next_pin        = 1;
+static u8              next_line       = 3;
+static u8              next_dev        = 1;
+static struct rb_root  pci_tree        = RB_ROOT;
+
+static struct pci_dev *search(struct rb_root *root, u32 id)
+{
+       struct rb_node *node = root->rb_node;
+
+       while (node) {
+               struct pci_dev *data = container_of(node, struct pci_dev, node);
+               int result;
+
+               result = id - data->id;
+
+               if (result < 0)
+                       node = node->rb_left;
+               else if (result > 0)
+                       node = node->rb_right;
+               else
+                       return data;
+       }
+       return NULL;
+}
+
+static int insert(struct rb_root *root, struct pci_dev *data)
+{
+       struct rb_node **new = &(root->rb_node), *parent = NULL;
+
+       /* Figure out where to put new node */
+       while (*new) {
+               struct pci_dev *this    = container_of(*new, struct pci_dev, node);
+               int result              = data->id - this->id;
+
+               parent = *new;
+               if (result < 0)
+                       new = &((*new)->rb_left);
+               else if (result > 0)
+                       new = &((*new)->rb_right);
+               else
+                       return 0;
+       }
+
+       /* Add new node and rebalance tree. */
+       rb_link_node(&data->node, parent, new);
+       rb_insert_color(&data->node, root);
+
+       return 1;
+}
+
+int irq__register_device(u32 dev, u8 *num, u8 *pin, u8 *line)
+{
+       struct pci_dev *node;
+
+       node = search(&pci_tree, dev);
+
+       if (!node) {
+               /* We haven't found a node - First device of it's kind */
+               node = malloc(sizeof(*node));
+               if (node == NULL)
+                       return -1;
+
+               *node = (struct pci_dev) {
+                       .id     = dev,
+                       .pin    = next_pin++,
+               };
+
+               INIT_LIST_HEAD(&node->lines);
+
+               if (insert(&pci_tree, node) != 1) {
+                       free(node);
+                       return -1;
+               }
+       }
+
+       if (node) {
+               /* This device already has a pin assigned, give out a new line and device id */
+               struct irq_line *new = malloc(sizeof(*new));
+               if (new == NULL)
+                       return -1;
+
+               new->line       = next_line++;
+               *line           = new->line;
+               *pin            = node->pin;
+               *num            = next_dev++;
+
+               list_add(&new->node, &node->lines);
+
+               return 0;
+       }
+
+       return -1;
+}
+
+struct rb_node *irq__get_pci_tree(void)
+{
+       return rb_first(&pci_tree);
+}