[Xen-changelog] [qemu-upstream-unstable] Xen PV backend: Move call to bdrv_new from blk_init to blk_connect

[patchbot@xxxxxxx]

commit 2d9b78b602494464ccae7667e655c962db9c3a65
Author:     Alex Bligh <alex@xxxxxxxxxxx>
AuthorDate: Fri Apr 5 15:45:10 2013 +0000
Commit:     Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
CommitDate: Fri Apr 5 23:30:59 2013 +0000

    Xen PV backend: Move call to bdrv_new from blk_init to blk_connect
    
    This commit delays the point at which bdrv_new (and hence blk_open
    on the underlying device) is called from blk_init to blk_connect.
    This ensures that in an inbound live migrate, the block device is
    not opened until it has been closed at the other end. This is in
    preparation for supporting devices with open/close consistency
    without using O_DIRECT. This commit does NOT itself change O_DIRECT
    semantics.
    
    upstream-commit-id: 86f425db3b1c4b6c4a2927eaec35627f9ab2e703
    
    Signed-off-by: Alex Bligh <alex@xxxxxxxxxxx>
    Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
---
 hw/xen_disk.c |   72 +++++++++++++++++++++++++++++++-------------------------
 1 files changed, 40 insertions(+), 32 deletions(-)

diff --git a/hw/xen_disk.c b/hw/xen_disk.c
index 69e1d9d..c3c5904 100644
--- a/hw/xen_disk.c
+++ b/hw/xen_disk.c
@@ -701,7 +701,7 @@ 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) {
@@ -744,10 +744,7 @@ 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;
     }
 
@@ -756,6 +753,41 @@ 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_NOCACHE | 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);
@@ -771,7 +803,7 @@ static int blk_init(struct XenDevice *xendev)
             }
         }
         if (!blkdev->bs) {
-            goto out_error;
+            return -1;
         }
     } else {
         /* setup via qemu cmdline -> already setup for us */
@@ -779,7 +811,6 @@ 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",
@@ -793,33 +824,10 @@ 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);
+    /* Fill in number of sector size and number of sectors */
+    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;
 
     if (xenstore_read_fe_int(&blkdev->xendev, "ring-ref", &blkdev->ring_ref) 
== -1) {
         return -1;
--
generated by git-patchbot for /home/xen/git/qemu-upstream-unstable.git

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