Merge remote-tracking branch 'sstabellini/xen-2013-04-05' into staging

# By Alex Bligh (2) and Felipe Franciosi (2)
# Via Stefano Stabellini
* sstabellini/xen-2013-04-05:
  Allow xen guests to plug disks of 1 TiB or more
  Introduce 64 bit integer write interface to xenstore
  Xen PV backend: Disable use of O_DIRECT by default as it results in crashes.
  Xen PV backend: Move call to bdrv_new from blk_init to blk_connect

hw/xen_backend.c

@@ -85,12 +85,20 @@ char *xenstore_read_str(const char *base, const char *node)
 
 int xenstore_write_int(const char *base, const char *node, int ival)
 {
-    char val[32];
+    char val[12];
 
     snprintf(val, sizeof(val), "%d", ival);
     return xenstore_write_str(base, node, val);
 }
 
+int xenstore_write_int64(const char *base, const char *node, int64_t ival)
+{
+    char val[21];
+
+    snprintf(val, sizeof(val), "%"PRId64, ival);
+    return xenstore_write_str(base, node, val);
+}
+
 int xenstore_read_int(const char *base, const char *node, int *ival)
 {
     char *val;
@@ -114,6 +122,11 @@ int xenstore_write_be_int(struct XenDevice *xendev, const char *node, int ival)
     return xenstore_write_int(xendev->be, node, ival);
 }
 
+int xenstore_write_be_int64(struct XenDevice *xendev, const char *node, int64_t ival)
+{
+    return xenstore_write_int64(xendev->be, node, ival);
+}
+
 char *xenstore_read_be_str(struct XenDevice *xendev, const char *node)
 {
     return xenstore_read_str(xendev->be, node);

hw/xen_backend.h

@@ -63,11 +63,13 @@ extern const char *xen_protocol;
 /* xenstore helper functions */
 int xenstore_write_str(const char *base, const char *node, const char *val);
 int xenstore_write_int(const char *base, const char *node, int ival);
+int xenstore_write_int64(const char *base, const char *node, int64_t ival);
 char *xenstore_read_str(const char *base, const char *node);
 int xenstore_read_int(const char *base, const char *node, int *ival);
 
 int xenstore_write_be_str(struct XenDevice *xendev, const char *node, const char *val);
 int xenstore_write_be_int(struct XenDevice *xendev, const char *node, int ival);
+int xenstore_write_be_int64(struct XenDevice *xendev, const char *node, int64_t ival);
 char *xenstore_read_be_str(struct XenDevice *xendev, const char *node);
 int xenstore_read_be_int(struct XenDevice *xendev, const char *node, int *ival);
 char *xenstore_read_fe_str(struct XenDevice *xendev, const char *node);

hw/xen_disk.c

@@ -700,7 +700,7 @@ static void blk_alloc(struct XenDevice *xendev)
 static int blk_init(struct XenDevice *xendev)
 {
     struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
-    int index, qflags, info = 0;
+    int info = 0;
 
     /* read xenstore entries */
     if (blkdev->params == NULL) {
@@ -743,10 +743,7 @@ static int blk_init(struct XenDevice *xendev)
     }
 
     /* read-only ? */
-    qflags = BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NATIVE_AIO;
-    if (strcmp(blkdev->mode, "w") == 0) {
-        qflags |= BDRV_O_RDWR;
-    } else {
+    if (strcmp(blkdev->mode, "w")) {
         info  |= VDISK_READONLY;
     }
 
@@ -755,6 +752,41 @@ static int blk_init(struct XenDevice *xendev)
         info  |= VDISK_CDROM;
     }
 
+    blkdev->file_blk  = BLOCK_SIZE;
+
+    /* fill info
+     * blk_connect supplies sector-size and sectors
+     */
+    xenstore_write_be_int(&blkdev->xendev, "feature-flush-cache", 1);
+    xenstore_write_be_int(&blkdev->xendev, "feature-persistent", 1);
+    xenstore_write_be_int(&blkdev->xendev, "info", info);
+    return 0;
+
+out_error:
+    g_free(blkdev->params);
+    blkdev->params = NULL;
+    g_free(blkdev->mode);
+    blkdev->mode = NULL;
+    g_free(blkdev->type);
+    blkdev->type = NULL;
+    g_free(blkdev->dev);
+    blkdev->dev = NULL;
+    g_free(blkdev->devtype);
+    blkdev->devtype = NULL;
+    return -1;
+}
+
+static int blk_connect(struct XenDevice *xendev)
+{
+    struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
+    int pers, index, qflags;
+
+    /* read-only ? */
+    qflags = BDRV_O_CACHE_WB | BDRV_O_NATIVE_AIO;
+    if (strcmp(blkdev->mode, "w") == 0) {
+        qflags |= BDRV_O_RDWR;
+    }
+
     /* init qemu block driver */
     index = (blkdev->xendev.dev - 202 * 256) / 16;
     blkdev->dinfo = drive_get(IF_XEN, 0, index);
@@ -770,7 +802,7 @@ static int blk_init(struct XenDevice *xendev)
             }
         }
         if (!blkdev->bs) {
-            goto out_error;
+            return -1;
         }
     } else {
         /* setup via qemu cmdline -> already setup for us */
@@ -778,7 +810,6 @@ static int blk_init(struct XenDevice *xendev)
         blkdev->bs = blkdev->dinfo->bdrv;
     }
     bdrv_attach_dev_nofail(blkdev->bs, blkdev);
-    blkdev->file_blk  = BLOCK_SIZE;
     blkdev->file_size = bdrv_getlength(blkdev->bs);
     if (blkdev->file_size < 0) {
         xen_be_printf(&blkdev->xendev, 1, "bdrv_getlength: %d (%s) | drv %s\n",
@@ -792,33 +823,10 @@ static int blk_init(struct XenDevice *xendev)
                   blkdev->type, blkdev->fileproto, blkdev->filename,
                   blkdev->file_size, blkdev->file_size >> 20);
 
-    /* fill info */
-    xenstore_write_be_int(&blkdev->xendev, "feature-flush-cache", 1);
-    xenstore_write_be_int(&blkdev->xendev, "feature-persistent", 1);
-    xenstore_write_be_int(&blkdev->xendev, "info",            info);
-    xenstore_write_be_int(&blkdev->xendev, "sector-size",     blkdev->file_blk);
-    xenstore_write_be_int(&blkdev->xendev, "sectors",
-                          blkdev->file_size / blkdev->file_blk);
-    return 0;
-
-out_error:
-    g_free(blkdev->params);
-    blkdev->params = NULL;
-    g_free(blkdev->mode);
-    blkdev->mode = NULL;
-    g_free(blkdev->type);
-    blkdev->type = NULL;
-    g_free(blkdev->dev);
-    blkdev->dev = NULL;
-    g_free(blkdev->devtype);
-    blkdev->devtype = NULL;
-    return -1;
-}
-
-static int blk_connect(struct XenDevice *xendev)
-{
-    struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
-    int pers;
+    /* Fill in number of sector size and number of sectors */
+    xenstore_write_be_int(&blkdev->xendev, "sector-size", blkdev->file_blk);
+    xenstore_write_be_int64(&blkdev->xendev, "sectors",
+                            blkdev->file_size / blkdev->file_blk);
 
     if (xenstore_read_fe_int(&blkdev->xendev, "ring-ref", &blkdev->ring_ref) == -1) {
         return -1;