diff mbox

[v2,2/2] block: gluster - add reopen support.

Message ID a3dd95f264d3d53af7d4026b0da175ce08aa0355.1392653229.git.jcody@redhat.com
State New
Headers show

Commit Message

Jeff Cody Feb. 17, 2014, 4:11 p.m. UTC
Gluster does parse open flags in its .bdrv_open() implementation,
and the .bdrv_reopen_* implementations need to do the same.

A new gluster connection to the image file to be created is established
in the .bdrv_reopen_prepare(), and the image file opened with the new
flags.

If this is successful, then the old image file is closed, and the
old connection torn down. The relevant structure pointers in the gluster
state structure are updated to the new connection.

If it is not successful, then the new file handle and connection is
abandoned (if it exists), while the old connection is not modified at
all.

With reopen supported, block-commit (and offline commit) is now also
supported for image files whose base image uses the native gluster
protocol driver.

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/gluster.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 102 insertions(+)

Comments

Stefan Hajnoczi Feb. 26, 2014, 3:04 p.m. UTC | #1
On Mon, Feb 17, 2014 at 11:11:12AM -0500, Jeff Cody wrote:
> +static int qemu_gluster_reopen_prepare(BDRVReopenState *state,
> +                                       BlockReopenQueue *queue, Error **errp)
> +{
> +    int ret = 0;
> +    BDRVGlusterReopenState *reop_s;
> +    GlusterConf *gconf = NULL;
> +    int open_flags = 0;
> +
> +    assert(state != NULL);
> +    assert(state->bs != NULL);
> +
> +    state->opaque = g_malloc0(sizeof(BDRVGlusterReopenState));

Not worth respinning but if you use the type name, then the more concise
notation is:

state->opaque = g_new0(BDRVGlusterReopenState, 1);
diff mbox

Patch

diff --git a/block/gluster.c b/block/gluster.c
index bcc9b89..f4756b8 100644
--- a/block/gluster.c
+++ b/block/gluster.c
@@ -338,6 +338,96 @@  out:
     return ret;
 }
 
+typedef struct BDRVGlusterReopenState {
+    struct glfs *glfs;
+    struct glfs_fd *fd;
+} BDRVGlusterReopenState;
+
+
+static int qemu_gluster_reopen_prepare(BDRVReopenState *state,
+                                       BlockReopenQueue *queue, Error **errp)
+{
+    int ret = 0;
+    BDRVGlusterReopenState *reop_s;
+    GlusterConf *gconf = NULL;
+    int open_flags = 0;
+
+    assert(state != NULL);
+    assert(state->bs != NULL);
+
+    state->opaque = g_malloc0(sizeof(BDRVGlusterReopenState));
+    reop_s = state->opaque;
+
+    qemu_gluster_parse_flags(state->flags, &open_flags);
+
+    gconf = g_malloc0(sizeof(GlusterConf));
+
+    reop_s->glfs = qemu_gluster_init(gconf, state->bs->filename);
+    if (reop_s->glfs == NULL) {
+        ret = -errno;
+        goto exit;
+    }
+
+    reop_s->fd = glfs_open(reop_s->glfs, gconf->image, open_flags);
+    if (reop_s->fd == NULL) {
+        /* reops->glfs will be cleaned up in _abort */
+        ret = -errno;
+        goto exit;
+    }
+
+exit:
+    /* state->opaque will be freed in either the _abort or _commit */
+    qemu_gluster_gconf_free(gconf);
+    return ret;
+}
+
+static void qemu_gluster_reopen_commit(BDRVReopenState *state)
+{
+    BDRVGlusterReopenState *reop_s = state->opaque;
+    BDRVGlusterState *s = state->bs->opaque;
+
+
+    /* close the old */
+    if (s->fd) {
+        glfs_close(s->fd);
+    }
+    if (s->glfs) {
+        glfs_fini(s->glfs);
+    }
+
+    /* use the newly opened image / connection */
+    s->fd         = reop_s->fd;
+    s->glfs       = reop_s->glfs;
+
+    g_free(state->opaque);
+    state->opaque = NULL;
+
+    return;
+}
+
+
+static void qemu_gluster_reopen_abort(BDRVReopenState *state)
+{
+    BDRVGlusterReopenState *reop_s = state->opaque;
+
+    if (reop_s == NULL) {
+        return;
+    }
+
+    if (reop_s->fd) {
+        glfs_close(reop_s->fd);
+    }
+
+    if (reop_s->glfs) {
+        glfs_fini(reop_s->glfs);
+    }
+
+    g_free(state->opaque);
+    state->opaque = NULL;
+
+    return;
+}
+
 #ifdef CONFIG_GLUSTERFS_ZEROFILL
 static coroutine_fn int qemu_gluster_co_write_zeroes(BlockDriverState *bs,
         int64_t sector_num, int nb_sectors, BdrvRequestFlags flags)
@@ -628,6 +718,9 @@  static BlockDriver bdrv_gluster = {
     .instance_size                = sizeof(BDRVGlusterState),
     .bdrv_needs_filename          = true,
     .bdrv_file_open               = qemu_gluster_open,
+    .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
+    .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
+    .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
     .bdrv_close                   = qemu_gluster_close,
     .bdrv_create                  = qemu_gluster_create,
     .bdrv_getlength               = qemu_gluster_getlength,
@@ -652,6 +745,9 @@  static BlockDriver bdrv_gluster_tcp = {
     .instance_size                = sizeof(BDRVGlusterState),
     .bdrv_needs_filename          = true,
     .bdrv_file_open               = qemu_gluster_open,
+    .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
+    .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
+    .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
     .bdrv_close                   = qemu_gluster_close,
     .bdrv_create                  = qemu_gluster_create,
     .bdrv_getlength               = qemu_gluster_getlength,
@@ -676,6 +772,9 @@  static BlockDriver bdrv_gluster_unix = {
     .instance_size                = sizeof(BDRVGlusterState),
     .bdrv_needs_filename          = true,
     .bdrv_file_open               = qemu_gluster_open,
+    .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
+    .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
+    .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
     .bdrv_close                   = qemu_gluster_close,
     .bdrv_create                  = qemu_gluster_create,
     .bdrv_getlength               = qemu_gluster_getlength,
@@ -700,6 +799,9 @@  static BlockDriver bdrv_gluster_rdma = {
     .instance_size                = sizeof(BDRVGlusterState),
     .bdrv_needs_filename          = true,
     .bdrv_file_open               = qemu_gluster_open,
+    .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
+    .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
+    .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
     .bdrv_close                   = qemu_gluster_close,
     .bdrv_create                  = qemu_gluster_create,
     .bdrv_getlength               = qemu_gluster_getlength,