[Qemu-devel] [PATCH RFC V1 01/11] Introduce HostPCIDevice to access a pci device on the host.

[Anthony PERARD <anthony.perard@citrix.com>]

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
---
 hw/host-pci-device.c |  192 ++++++++++++++++++++++++++++++++++++++++++++++++++
 hw/host-pci-device.h |   36 +++++++++
 2 files changed, 228 insertions(+), 0 deletions(-)
 create mode 100644 hw/host-pci-device.c
 create mode 100644 hw/host-pci-device.h

diff --git a/hw/host-pci-device.c b/hw/host-pci-device.c
new file mode 100644
index 0000000..b3f2899
--- /dev/null
+++ b/hw/host-pci-device.c
@@ -0,0 +1,192 @@
+#include "qemu-common.h"
+#include "host-pci-device.h"
+
+static int path_to(const HostPCIDevice *d,
+                   const char *name, char *buf, ssize_t size)
+{
+    return snprintf(buf, size, "/sys/bus/pci/devices/%04x:%02x:%02x.%x/%s",
+                    d->domain, d->bus, d->dev, d->func, name);
+}
+
+static int get_resource(HostPCIDevice *d)
+{
+    int i;
+    FILE *f;
+    char path[PATH_MAX];
+    unsigned long long start, end, flags, size;
+
+    path_to(d, "resource", path, sizeof (path));
+    f = fopen(path, "r");
+    if (!f) {
+        fprintf(stderr, "Error: Can't open %s: %s\n", path, strerror(errno));
+        return -1;
+    }
+
+    for (i = 0; i < PCI_NUM_REGIONS; i++) {
+        if (fscanf(f, "%llx %llx %llx", &start, &end, &flags) != 3) {
+            fprintf(stderr, "Error: Syntax error in %s\n", path);
+            break;
+        }
+        if (start) {
+            size = end - start + 1;
+        } else {
+            size = 0;
+        }
+
+        flags &= 0xf;
+
+        if (i < PCI_ROM_SLOT) {
+            d->base_addr[i] = start | flags;
+            d->size[i] = size;
+        } else {
+            d->rom_base_addr = start | flags;
+            d->rom_size = size;
+        }
+    }
+
+    fclose(f);
+    return 0;
+}
+
+static unsigned long get_value(HostPCIDevice *d, const char *name)
+{
+    char path[PATH_MAX];
+    FILE *f;
+    unsigned long value;
+
+    path_to(d, name, path, sizeof (path));
+    f = fopen(path, "r");
+    if (!f) {
+        fprintf(stderr, "Error: Can't open %s: %s\n", path, strerror(errno));
+        return -1;
+    }
+    if (fscanf(f, "%lx\n", &value) != 1) {
+        fprintf(stderr, "Error: Syntax error in %s\n", path);
+        value = -1;
+    }
+    fclose(f);
+    return value;
+}
+
+static int pci_dev_is_virtfn(HostPCIDevice *d)
+{
+    int rc;
+    char path[PATH_MAX];
+    struct stat buf;
+
+    path_to(d, "physfn", path, sizeof (path));
+    rc = !stat(path, &buf);
+
+    return rc;
+}
+
+static int host_pci_config_fd(HostPCIDevice *d)
+{
+    char path[PATH_MAX];
+
+    if (d->config_fd < 0) {
+        path_to(d, "config", path, sizeof (path));
+        d->config_fd = open(path, O_RDWR);
+        if (d->config_fd < 0) {
+            fprintf(stderr, "HostPCIDevice: Can not open '%s': %s\n",
+                    path, strerror(errno));
+        }
+    }
+    return d->config_fd;
+}
+static int host_pci_config_read(HostPCIDevice *d, int pos, void *buf, int len)
+{
+    int fd = host_pci_config_fd(d);
+    int res = 0;
+
+    res = pread(fd, buf, len, pos);
+    if (res < 0) {
+        fprintf(stderr, "host_pci_config: read failed: %s (fd: %i)\n",
+                strerror(errno), fd);
+        return -1;
+    }
+    return res;
+}
+static int host_pci_config_write(HostPCIDevice *d,
+                                 int pos, const void *buf, int len)
+{
+    int fd = host_pci_config_fd(d);
+    int res = 0;
+
+    res = pwrite(fd, buf, len, pos);
+    if (res < 0) {
+        fprintf(stderr, "host_pci_config: write failed: %s\n",
+                strerror(errno));
+        return -1;
+    }
+    return res;
+}
+
+uint8_t host_pci_read_byte(HostPCIDevice *d, int pos)
+{
+  uint8_t buf;
+  host_pci_config_read(d, pos, &buf, 1);
+  return buf;
+}
+uint16_t host_pci_read_word(HostPCIDevice *d, int pos)
+{
+  uint16_t buf;
+  host_pci_config_read(d, pos, &buf, 2);
+  return le16_to_cpu(buf);
+}
+uint32_t host_pci_read_long(HostPCIDevice *d, int pos)
+{
+  uint32_t buf;
+  host_pci_config_read(d, pos, &buf, 4);
+  return le32_to_cpu(buf);
+}
+int host_pci_read_block(HostPCIDevice *d, int pos, uint8_t *buf, int len)
+{
+  return host_pci_config_read(d, pos, buf, len);
+}
+
+int host_pci_write_byte(HostPCIDevice *d, int pos, uint8_t data)
+{
+  return host_pci_config_write(d, pos, &data, 1);
+}
+int host_pci_write_word(HostPCIDevice *d, int pos, uint16_t data)
+{
+  return host_pci_config_write(d, pos, &data, 2);
+}
+int host_pci_write_long(HostPCIDevice *d, int pos, uint32_t data)
+{
+  return host_pci_config_write(d, pos, &data, 4);
+}
+int host_pci_write_block(HostPCIDevice *d, int pos, uint8_t *buf, int len)
+{
+  return host_pci_config_write(d, pos, buf, len);
+}
+
+HostPCIDevice *host_pci_device_get(uint8_t bus, uint8_t dev, uint8_t func)
+{
+    HostPCIDevice *d = NULL;
+
+    d = g_new0(HostPCIDevice, 1);
+
+    d->config_fd = -1;
+    d->domain = 0;
+    d->bus = bus;
+    d->dev = dev;
+    d->func = func;
+
+    if (host_pci_config_fd(d) == -1)
+        goto error;
+    if (get_resource(d) == -1)
+        goto error;
+
+    d->vendor_id = get_value(d, "vendor");
+    d->device_id = get_value(d, "device");
+    d->is_virtfn = pci_dev_is_virtfn(d);
+
+    return d;
+error:
+    if (d->config_fd >= 0)
+        close(d->config_fd);
+    g_free(d);
+    return NULL;
+}
diff --git a/hw/host-pci-device.h b/hw/host-pci-device.h
new file mode 100644
index 0000000..0137507
--- /dev/null
+++ b/hw/host-pci-device.h
@@ -0,0 +1,36 @@
+#ifndef HW_HOST_PCI_DEVICE
+#  define HW_HOST_PCI_DEVICE
+
+#include "pci.h"
+
+typedef struct HostPCIDevice {
+    uint16_t domain;
+    uint8_t bus;
+    uint8_t dev;
+    uint8_t func;
+
+    uint16_t vendor_id;
+    uint16_t device_id;
+
+    pcibus_t base_addr[PCI_NUM_REGIONS - 1];
+    pcibus_t size[PCI_NUM_REGIONS - 1];
+    pcibus_t rom_base_addr;
+    pcibus_t rom_size;
+
+    bool is_virtfn;
+
+    int config_fd;
+} HostPCIDevice;
+
+HostPCIDevice *host_pci_device_get(uint8_t bus, uint8_t dev, uint8_t func);
+
+uint8_t host_pci_read_byte(HostPCIDevice *d, int pos);
+uint16_t host_pci_read_word(HostPCIDevice *d, int pos);
+uint32_t host_pci_read_long(HostPCIDevice *d, int pos);
+int host_pci_read_block(HostPCIDevice *d, int pos, uint8_t *buf, int len);
+int host_pci_write_byte(HostPCIDevice *d, int pos, uint8_t data);
+int host_pci_write_word(HostPCIDevice *d, int pos, uint16_t data);
+int host_pci_write_long(HostPCIDevice *d, int pos, uint32_t data);
+int host_pci_write_block(HostPCIDevice *d, int pos, uint8_t *buf, int len);
+
+#endif /* !HW_HOST_PCI_DEVICE */
-- 
Anthony PERARD