BD Backend: CLI to create a full/linked clone of a image

A new CLI command added to support cloning/snapshotting of a LV device

Syntax is:
$ gluster bd clone <volname>:<vg>/<lv> <newlv>

$ gluster bd snapshot <volname>:<vg>/<lv> <snap_lv> <size>

BUG: 805138
Change-Id: Idc2ac14525a3998329c742bf85a06326cac8cd54
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Reviewed-on: http://review.gluster.org/3719
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

6 files changed, 170 insertions, 12 deletions

diff --git a/cli/src/cli-cmd-parser.c b/cli/src/cli-cmd-parser.c
index f7ee29a1..ae754b97 100644
--- a/cli/src/cli-cmd-parser.c
+++ b/cli/src/cli-cmd-parser.c
@@ -369,7 +369,7 @@ cli_cmd_volume_create_parse (const char **words, int wordcount, dict_t **options
                 cli_err ("Block Device backend volume does not support multiple"
                          " bricks");
                 gf_log ("", GF_LOG_ERROR,
-                          "Block Device backend volumer does not support multiple"
+                         "Block Device backend volume does not support multiple"
                         " bricks");
                 ret = -1;
                 goto out;
diff --git a/cli/src/cli-cmd-volume-bdevice.c b/cli/src/cli-cmd-volume-bdevice.c
index ea7edab6..19325754 100644
--- a/cli/src/cli-cmd-volume-bdevice.c
+++ b/cli/src/cli-cmd-volume-bdevice.c
@@ -41,6 +41,8 @@ cli_cmd_bd_parse (dict_t *dict, const char **words)
         char          *size     = NULL;
         char          *eptr     = NULL;
         gf_xl_bd_op_t  bd_op    = GF_BD_OP_INVALID;
+        char          *dest_lv  = NULL;
+
 
         /* volname:/path */
         if (!strchr (words[2], ':') || !strchr (words[2], '/')) {
@@ -64,6 +66,10 @@ cli_cmd_bd_parse (dict_t *dict, const char **words)
                 bd_op = GF_BD_OP_NEW_BD;
         else if (!strcasecmp (words[1], "delete"))
                 bd_op = GF_BD_OP_DELETE_BD;
+        else if (!strcasecmp (words[1], "clone"))
+                bd_op = GF_BD_OP_CLONE_BD;
+        else if (!strcasecmp (words[1], "snapshot"))
+                bd_op = GF_BD_OP_SNAPSHOT_BD;
         else
                 return -1;
 
@@ -83,6 +89,30 @@ cli_cmd_bd_parse (dict_t *dict, const char **words)
                 ret = dict_set_dynstr (dict, "size", size);
                 if (ret)
                         goto out;
+        } else if (bd_op == GF_BD_OP_SNAPSHOT_BD ||
+                   bd_op == GF_BD_OP_CLONE_BD) {
+                /*
+                 * dest_lv should be just dest_lv, we don't support
+                 * cloning/snapshotting to a different volume or vg
+                 */
+                if (strchr (words[3], ':') || strchr (words[3], '/')) {
+                        cli_err ("invalid parameter %s, volname/vg not needed",
+                                 words[3]);
+                        ret = -1;
+                        goto out;
+                }
+                dest_lv = gf_strdup (words[3]);
+                ret = dict_set_dynstr (dict, "dest_lv", dest_lv);
+                if (ret)
+                        goto out;
+
+                /* clone needs size as parameter */
+                if (bd_op == GF_BD_OP_SNAPSHOT_BD) {
+                        ret = dict_set_dynstr (dict, "size",
+                                               gf_strdup (words[4]));
+                        if (ret)
+                                goto out;
+                }
         }
 
         ret = 0;
@@ -94,13 +124,15 @@ out:
 /*
  * bd create <volname>:/path <size>
  * bd delete <volname>:/path
+ * bd clone <volname>:/path <newbd>
+ * bd snapshot <volname>:/<path> <newbd> <size>
  */
 int32_t
 cli_cmd_bd_validate (const char **words, int wordcount, dict_t **options)
 {
         dict_t  *dict = NULL;
         int     ret   = -1;
-        char    *op[] = { "create", "delete", NULL };
+        char    *op[] = { "create", "delete", "clone", "snapshot", NULL };
         int     index = 0;
 
         for (index = 0; op[index]; index++)
@@ -120,6 +152,12 @@ cli_cmd_bd_validate (const char **words, int wordcount, dict_t **options)
         } else if (!strcasecmp (words[1], "delete")) {
                 if (wordcount != 3)
                         goto out;
+        } else if (!strcasecmp (words[1], "clone")) {
+                if (wordcount != 4)
+                        goto out;
+        } else if (!strcasecmp (words[1], "snapshot")) {
+                if (wordcount != 5)
+                        goto out;
         } else {
                 ret = -1;
                 goto out;
@@ -193,6 +231,13 @@ struct cli_cmd cli_bd_cmds[] = {
         { "bd delete <volname>:<bd>",
           cli_cmd_bd_cbk,
           "Delete a block device"},
+        { "bd clone <volname>:<bd> <newbd>",
+          cli_cmd_bd_cbk,
+          "clone device"},
+        { "bd snapshot <volname>:<bd> <newbd> <size>",
+          cli_cmd_bd_cbk,
+          "\n\tsnapshot device where size can be "
+          "suffixed with KB, MB etc. Default size is in MB"},
         { NULL, NULL, NULL }
 };
 
diff --git a/cli/src/cli-rpc-ops.c b/cli/src/cli-rpc-ops.c
index 9e4e03d0..da239b51 100644
--- a/cli/src/cli-rpc-ops.c
+++ b/cli/src/cli-rpc-ops.c
@@ -2647,6 +2647,12 @@ gf_cli_bd_op_cbk (struct rpc_req *req, struct iovec *iov,
         case GF_BD_OP_DELETE_BD:
                 operation = gf_strdup ("delete");
                 break;
+        case GF_BD_OP_CLONE_BD:
+                operation = gf_strdup ("clone");
+                break;
+        case GF_BD_OP_SNAPSHOT_BD:
+                operation = gf_strdup ("snapshot");
+                break;
         default:
                 break;
         }
diff --git a/rpc/rpc-lib/src/protocol-common.h b/rpc/rpc-lib/src/protocol-common.h
index 38528bd5..97017e5f 100644
--- a/rpc/rpc-lib/src/protocol-common.h
+++ b/rpc/rpc-lib/src/protocol-common.h
@@ -211,6 +211,8 @@ typedef enum {
         GF_BD_OP_INVALID,
         GF_BD_OP_NEW_BD,
         GF_BD_OP_DELETE_BD,
+        GF_BD_OP_CLONE_BD,
+        GF_BD_OP_SNAPSHOT_BD,
 } gf_xl_bd_op_t ;
 
 #define GLUSTER_HNDSK_PROGRAM    14398633 /* Completely random */
diff --git a/xlators/mgmt/glusterd/src/glusterd-volume-ops.c b/xlators/mgmt/glusterd/src/glusterd-volume-ops.c
index b74bbec7..db143d5f 100644
--- a/xlators/mgmt/glusterd/src/glusterd-volume-ops.c
+++ b/xlators/mgmt/glusterd/src/glusterd-volume-ops.c
@@ -1295,6 +1295,24 @@ glusterd_op_stage_bd (dict_t *dict, char **op_errstr)
                         ret = -1;
                         goto out;
                 }
+        } else if (bd_op == GF_BD_OP_SNAPSHOT_BD) {
+                ret = dict_get_str (dict, "size", &size);
+                if (ret) {
+                        snprintf (msg, sizeof(msg), "Failed to get size");
+                        gf_log ("", GF_LOG_ERROR, "%s", msg);
+                        *op_errstr = gf_strdup (msg);
+                        goto out;
+                }
+
+                if (gf_string2bytesize (size, &bytes) < 0) {
+                        ret = -1;
+                        snprintf (msg, sizeof(msg),
+                                "Invalid size %s, suffix with KB, MB etc",
+                                size);
+                        gf_log ("", GF_LOG_ERROR, "%s", msg);
+                        *op_errstr = gf_strdup (msg);
+                        goto out;
+                }
         }
 
         ret = glusterd_volinfo_find (volname, &volinfo);
@@ -1324,7 +1342,6 @@ out:
         gf_log ("", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
 }
-
 #endif
 
 int
diff --git a/xlators/storage/bd_map/src/bd_map.c b/xlators/storage/bd_map/src/bd_map.c
index a84ee29f..9c8f69c6 100644
--- a/xlators/storage/bd_map/src/bd_map.c
+++ b/xlators/storage/bd_map/src/bd_map.c
@@ -371,10 +371,6 @@ int bd_clone_lv (bd_priv_t *priv, bd_entry_t *p_entry, dict_t *output,
         ret = 0;
         gf_log (THIS->name, GF_LOG_INFO, "Clone completed");
 out:
-        for (i = 0; i < IOV_NR; i++) {
-                if (vec[i].iov_base)
-                        GF_FREE (vec[i].iov_base);
-        }
         if (vg)
                 lvm_vg_close (vg);
         if (fd1 != -1)
@@ -387,7 +383,7 @@ out:
 }
 
 int bd_snapshot_lv (bd_priv_t *priv, bd_entry_t *p_entry, dict_t *output,
-                    const char *lv_name, const char *dest_lv, uint64_t size,
+                    const char *lv_name, const char *dest_lv, char *size,
                     struct iatt *stbuf)
 {
         int32_t         ret      = -1;
@@ -408,7 +404,7 @@ int bd_snapshot_lv (bd_priv_t *priv, bd_entry_t *p_entry, dict_t *output,
         runner_argprintf (&runner, "/dev/%s/%s", p_entry->name, lv_name);
         runner_add_args  (&runner, "--name", NULL);
         runner_argprintf (&runner, "%s", dest_lv);
-        runner_argprintf (&runner, "-L%ld", size);
+        runner_argprintf (&runner, "-L%s", size);
 
         runner_start (&runner);
         runner_end (&runner);
@@ -534,7 +530,7 @@ bd_symlink (call_frame_t *frame, xlator_t *this,
 
         memcpy (&preparent, lventry->parent->attr, sizeof(preparent));
         if (bd_snapshot_lv (priv, lventry->parent, NULL, lventry->name,
-                            name, 1, &stbuf) < 0) {
+                            name, "1", &stbuf) < 0) {
                 op_errno = EAGAIN;
                 goto out;
         }
@@ -2232,6 +2228,94 @@ out:
         return ret;
 }
 
+int bd_xl_op_clone(bd_priv_t *priv, int subop, dict_t *input, dict_t *output)
+{
+        bd_entry_t      *p_entry = NULL;
+        bd_entry_t      *lventry = NULL;
+        int             ret      = -1;
+        char            *error   = NULL;
+        int             retval   = -1;
+        char            *vg      = NULL;
+        char            *lv      = NULL;
+        char            *dest_lv = NULL;
+        char            *size    = NULL;
+        char            *buff    = NULL;
+        char            *buffp   = NULL;
+        char            *path    = NULL;
+        char            *save    = NULL;
+        char            *npath   = NULL;
+
+        ret = dict_get_str (input, "path", &path);
+        ret = dict_get_str (input, "dest_lv", &dest_lv);
+        ret = dict_get_str (input, "size", &size);
+
+        if (!path || !dest_lv) {
+                gf_asprintf (&error, "invalid arguments");
+                ret = -1;
+                goto out;
+        }
+
+        buff = buffp = gf_strdup (path);
+
+        vg = strtok_r (buff, "/", &save);
+        lv = strtok_r (NULL, "/", &save);
+        if (!lv) {
+                gf_asprintf (&error, "lv not given %s", path);
+                ret = -1;
+                goto out;
+        }
+
+        BD_ENTRY (priv, p_entry, vg);
+        if (!p_entry) {
+                gf_asprintf (&error, "%s does not exist", vg);
+                retval = dict_set_str (output, "error", error);
+                goto out;
+        }
+
+        BD_ENTRY (priv, lventry, path);
+        if (!lventry) {
+                gf_asprintf (&error, "%s does not exist", path);
+                ret = -1;
+                goto out;
+        }
+        BD_PUT_ENTRY (priv, lventry);
+        lventry = NULL;
+        gf_asprintf (&npath, "/%s/%s", vg, dest_lv);
+        BD_ENTRY (priv, lventry, npath);
+        if (lventry) {
+                gf_asprintf (&error, "%s already exists", dest_lv);
+                BD_PUT_ENTRY (priv, lventry);
+                ret = -1;
+                goto out;
+        }
+
+        if (subop == GF_BD_OP_SNAPSHOT_BD) {
+                if (!size) {
+                        gf_asprintf (&error, "size not given");
+                        ret = -1;
+                        goto out;
+                }
+                ret = bd_snapshot_lv (priv, p_entry, output, lv, dest_lv,
+                                  size, NULL);
+        } else
+                ret = bd_clone_lv (priv, p_entry, output, vg, lv, dest_lv,
+                                  NULL);
+
+        if (ret)
+                goto out;
+        ret = 0;
+out:
+        if (error)
+                retval = dict_set_dynstr (output, "error", error);
+        if (p_entry)
+                BD_PUT_ENTRY (priv, p_entry);
+        if (npath)
+                GF_FREE (npath);
+        if (buffp)
+                GF_FREE (buffp);
+        return ret;
+}
+
 int32_t
 bd_notify (xlator_t *this, dict_t *input, dict_t *output)
 {
@@ -2246,7 +2330,7 @@ bd_notify (xlator_t *this, dict_t *input, dict_t *output)
 
         ret = dict_get_int32 (input, "bd-op", (int32_t *)&bdop);
         if (ret) {
-                asprintf (&error, "no sub-op specified");
+                gf_asprintf (&error, "no sub-op specified");
                 goto out;
         }
 
@@ -2258,6 +2342,10 @@ bd_notify (xlator_t *this, dict_t *input, dict_t *output)
         case GF_BD_OP_DELETE_BD:
                 ret = bd_xl_op_delete (priv, input, output);
                 break;
+        case GF_BD_OP_CLONE_BD:
+        case GF_BD_OP_SNAPSHOT_BD:
+                ret = bd_xl_op_clone (priv, bdop, input, output);
+                break;
         default:
                 gf_asprintf (&error, "invalid bd-op %d specified", bdop);
                 retval = dict_set_dynstr (output, "error", error);
@@ -2278,7 +2366,7 @@ notify (xlator_t *this,
         ...)
 {
         va_list ap;
-        int     ret    = -1;
+        int     ret    = 0;
         void    *data2 = NULL;
         dict_t  *input = NULL;
         dict_t  *output = NULL;