[Qemu-devel] [PATCH 16/18] virtio-blk: fix initialization for version 1.0

[Gerd Hoffmann <kraxel@redhat.com>]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 src/hw/virtio-blk.c | 85 +++++++++++++++++++++++++++++++++++++++++------------
 src/hw/virtio-pci.h | 13 ++++----
 2 files changed, 72 insertions(+), 26 deletions(-)

diff --git a/src/hw/virtio-blk.c b/src/hw/virtio-blk.c
index 9e56d42..b7c24f8 100644
--- a/src/hw/virtio-blk.c
+++ b/src/hw/virtio-blk.c
@@ -102,6 +102,7 @@ static void
 init_virtio_blk(struct pci_device *pci)
 {
     u16 bdf = pci->bdf;
+    u8 status = VIRTIO_CONFIG_S_ACKNOWLEDGE | VIRTIO_CONFIG_S_DRIVER;
     dprintf(1, "found virtio-blk at %x:%x\n", pci_bdf_to_bus(bdf),
             pci_bdf_to_dev(bdf));
     struct virtiodrive_s *vdrive = malloc_fseg(sizeof(*vdrive));
@@ -113,42 +114,88 @@ init_virtio_blk(struct pci_device *pci)
     vdrive->drive.type = DTYPE_VIRTIO_BLK;
     vdrive->drive.cntl_id = bdf;
 
-    vdrive->vp = vp_init_simple(pci);
+    struct vp_device *vp = vdrive->vp = vp_init_simple(pci);
     if (vp_find_vq(vdrive->vp, 0, &vdrive->vq) < 0 ) {
         dprintf(1, "fail to find vq for virtio-blk %x:%x\n",
                 pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf));
         goto fail;
     }
 
-    struct virtio_blk_config cfg;
-    vp_get(vdrive->vp, 0, &cfg, sizeof(cfg));
+    if (vp->use_modern) {
+        u64 features = vp_get_features(vp);
+        u64 version1 = 1ull << VIRTIO_F_VERSION_1;
+        u64 blk_size = 1ull << VIRTIO_BLK_F_BLK_SIZE;
+        if (!(features & version1)) {
+            dprintf(1, "modern device without virtio_1 feature bit: %x:%x\n",
+                    pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf));
+            goto fail;
+        }
 
-    u64 f = vp_get_features(vdrive->vp);
-    vdrive->drive.blksize = (f & (1 << VIRTIO_BLK_F_BLK_SIZE)) ?
-        cfg.blk_size : DISK_SECTOR_SIZE;
+        features = features & (version1 | blk_size);
+        vp_set_features(vp, features);
+        status |= VIRTIO_CONFIG_S_FEATURES_OK;
+        vp_set_status(vp, status);
+        if (!(vp_get_status(vp) & VIRTIO_CONFIG_S_FEATURES_OK)) {
+            dprintf(1, "device didn't accept features: %x:%x\n",
+                    pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf));
+            goto fail;
+        }
 
-    vdrive->drive.sectors = cfg.capacity;
-    dprintf(3, "virtio-blk %x:%x blksize=%d sectors=%u\n",
-            pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf),
-            vdrive->drive.blksize, (u32)vdrive->drive.sectors);
+        vp_modern_read(vp->device, struct virtio_blk_config,
+                       capacity, vdrive->drive.sectors);
+        if (features & blk_size) {
+            vp_modern_read(vp->device, struct virtio_blk_config,
+                           blk_size, vdrive->drive.blksize);
+        } else {
+            vdrive->drive.blksize = DISK_SECTOR_SIZE;
+        }
+        if (vdrive->drive.blksize != DISK_SECTOR_SIZE) {
+            dprintf(1, "virtio-blk %x:%x block size %d is unsupported\n",
+                    pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf),
+                    vdrive->drive.blksize);
+            goto fail;
+        }
+        dprintf(3, "virtio-blk %x:%x blksize=%d sectors=%u\n",
+                pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf),
+                vdrive->drive.blksize, (u32)vdrive->drive.sectors);
+
+        vp_modern_read(vp->device, struct virtio_blk_config,
+                       cylinders, vdrive->drive.pchs.cylinder);
+        vp_modern_read(vp->device, struct virtio_blk_config,
+                       heads, vdrive->drive.pchs.head);
+        vp_modern_read(vp->device, struct virtio_blk_config,
+                       sectors, vdrive->drive.pchs.sector);
+    } else {
+        struct virtio_blk_config cfg;
+        vp_get_legacy(vdrive->vp, 0, &cfg, sizeof(cfg));
 
-    if (vdrive->drive.blksize != DISK_SECTOR_SIZE) {
-        dprintf(1, "virtio-blk %x:%x block size %d is unsupported\n",
+        u64 f = vp_get_features(vdrive->vp);
+        vdrive->drive.blksize = (f & (1 << VIRTIO_BLK_F_BLK_SIZE)) ?
+            cfg.blk_size : DISK_SECTOR_SIZE;
+
+        vdrive->drive.sectors = cfg.capacity;
+        dprintf(3, "virtio-blk %x:%x blksize=%d sectors=%u\n",
                 pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf),
-                vdrive->drive.blksize);
-        goto fail;
+                vdrive->drive.blksize, (u32)vdrive->drive.sectors);
+
+        if (vdrive->drive.blksize != DISK_SECTOR_SIZE) {
+            dprintf(1, "virtio-blk %x:%x block size %d is unsupported\n",
+                    pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf),
+                    vdrive->drive.blksize);
+            goto fail;
+        }
+        vdrive->drive.pchs.cylinder = cfg.cylinders;
+        vdrive->drive.pchs.head = cfg.heads;
+        vdrive->drive.pchs.sector = cfg.sectors;
     }
 
-    vdrive->drive.pchs.cylinder = cfg.cylinders;
-    vdrive->drive.pchs.head = cfg.heads;
-    vdrive->drive.pchs.sector = cfg.sectors;
     char *desc = znprintf(MAXDESCSIZE, "Virtio disk PCI:%x:%x",
                           pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf));
 
     boot_add_hd(&vdrive->drive, desc, bootprio_find_pci_device(pci));
 
-    vp_set_status(vdrive->vp, VIRTIO_CONFIG_S_ACKNOWLEDGE |
-                  VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK);
+    status |= VIRTIO_CONFIG_S_DRIVER_OK;
+    vp_set_status(vdrive->vp, status);
     return;
 
 fail:
diff --git a/src/hw/virtio-pci.h b/src/hw/virtio-pci.h
index 468eb6f..29ab775 100644
--- a/src/hw/virtio-pci.h
+++ b/src/hw/virtio-pci.h
@@ -192,15 +192,14 @@ struct vp_device {
 u64 vp_get_features(struct vp_device *vp);
 void vp_set_features(struct vp_device *vp, u64 features);
 
-static inline void vp_get(struct vp_device *vp, unsigned offset,
-                     void *buf, unsigned len)
+static inline void vp_get_legacy(struct vp_device *vp, unsigned offset,
+                                 void *buf, unsigned len)
 {
-   int ioaddr = GET_LOWFLAT(vp->ioaddr);
-   u8 *ptr = buf;
-   unsigned i;
+    u8 *ptr = buf;
+    unsigned i;
 
-   for (i = 0; i < len; i++)
-           ptr[i] = inb(ioaddr + VIRTIO_PCI_CONFIG + offset + i);
+    for (i = 0; i < len; i++)
+        ptr[i] = inb(vp->ioaddr + VIRTIO_PCI_CONFIG + offset + i);
 }
 
 u8 vp_get_status(struct vp_device *vp);
-- 
1.8.3.1