metadump: Introduce metadump v1 operations

This commit moves functionality associated with writing metadump to disk into
a new function. It also renames metadump initialization, write and release
functions to reflect the fact that they work with v1 metadump files.

The metadump initialization, write and release functions are now invoked via
metadump_ops->init(), metadump_ops->write() and metadump_ops->release()
respectively.

Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>

diff --git a/db/metadump.c b/db/metadump.c
index a2ec6ab569abf1ab0b38945d1e44c654ce360f85..c11503c71347db37ef2fbb003f1895adb482b2be 100644 (file)
--- a/db/metadump.c
+++ b/db/metadump.c
@@ -153,59 +153,6 @@ print_progress(const char *fmt, ...)
        metadump.progress_since_warning = true;
 }
 
-/*
- * A complete dump file will have a "zero" entry in the last index block,
- * even if the dump is exactly aligned, the last index will be full of
- * zeros. If the last index entry is non-zero, the dump is incomplete.
- * Correspondingly, the last chunk will have a count < num_indices.
- *
- * Return 0 for success, -1 for failure.
- */
-
-static int
-write_index(void)
-{
-       struct xfs_metablock *metablock = metadump.metablock;
-       /*
-        * write index block and following data blocks (streaming)
-        */
-       metablock->mb_count = cpu_to_be16(metadump.cur_index);
-       if (fwrite(metablock, (metadump.cur_index + 1) << BBSHIFT, 1,
-                       metadump.outf) != 1) {
-               print_warning("error writing to target file");
-               return -1;
-       }
-
-       memset(metadump.block_index, 0, metadump.num_indices * sizeof(__be64));
-       metadump.cur_index = 0;
-       return 0;
-}
-
-/*
- * Return 0 for success, -errno for failure.
- */
-static int
-write_buf_segment(
-       char            *data,
-       int64_t         off,
-       int             len)
-{
-       int             i;
-       int             ret;
-
-       for (i = 0; i < len; i++, off++, data += BBSIZE) {
-               metadump.block_index[metadump.cur_index] = cpu_to_be64(off);
-               memcpy(&metadump.block_buffer[metadump.cur_index << BBSHIFT],
-                               data, BBSIZE);
-               if (++metadump.cur_index == metadump.num_indices) {
-                       ret = write_index();
-                       if (ret)
-                               return -EIO;
-               }
-       }
-       return 0;
-}
-
 /*
  * we want to preserve the state of the metadata in the dump - whether it is
  * intact or corrupt, so even if the buffer has a verifier attached to it we
@@ -242,15 +189,17 @@ write_buf(
 
        /* handle discontiguous buffers */
        if (!buf->bbmap) {
-               ret = write_buf_segment(buf->data, buf->bb, buf->blen);
+               ret = metadump.mdops->write(buf->typ->typnm, buf->data, buf->bb,
+                               buf->blen);
                if (ret)
                        return ret;
        } else {
                int     len = 0;
                for (i = 0; i < buf->bbmap->nmaps; i++) {
-                       ret = write_buf_segment(buf->data + BBTOB(len),
-                                               buf->bbmap->b[i].bm_bn,
-                                               buf->bbmap->b[i].bm_len);
+                       ret = metadump.mdops->write(buf->typ->typnm,
+                                       buf->data + BBTOB(len),
+                                       buf->bbmap->b[i].bm_bn,
+                                       buf->bbmap->b[i].bm_len);
                        if (ret)
                                return ret;
                        len += buf->bbmap->b[i].bm_len;
@@ -2691,7 +2640,7 @@ done:
 }
 
 static int
-init_metadump(void)
+init_metadump_v1(void)
 {
        metadump.metablock = (xfs_metablock_t *)calloc(BBSIZE + 1, BBSIZE);
        if (metadump.metablock == NULL) {
@@ -2732,12 +2681,61 @@ init_metadump(void)
        return 0;
 }
 
+static int
+finish_dump_metadump_v1(void)
+{
+       /*
+        * write index block and following data blocks (streaming)
+        */
+       metadump.metablock->mb_count = cpu_to_be16(metadump.cur_index);
+       if (fwrite(metadump.metablock, (metadump.cur_index + 1) << BBSHIFT, 1,
+                       metadump.outf) != 1) {
+               print_warning("error writing to target file");
+               return -1;
+       }
+
+       memset(metadump.block_index, 0, metadump.num_indices * sizeof(__be64));
+       metadump.cur_index = 0;
+       return 0;
+}
+
+static int
+write_metadump_v1(
+       enum typnm      type,
+       const char      *data,
+       xfs_daddr_t     off,
+       int             len)
+{
+       int             i;
+       int             ret;
+
+       for (i = 0; i < len; i++, off++, data += BBSIZE) {
+               metadump.block_index[metadump.cur_index] = cpu_to_be64(off);
+               memcpy(&metadump.block_buffer[metadump.cur_index << BBSHIFT],
+                               data, BBSIZE);
+               if (++metadump.cur_index == metadump.num_indices) {
+                       ret = finish_dump_metadump_v1();
+                       if (ret)
+                               return -EIO;
+               }
+       }
+
+       return 0;
+}
+
 static void
-release_metadump(void)
+release_metadump_v1(void)
 {
        free(metadump.metablock);
 }
 
+static struct metadump_ops metadump1_ops = {
+       .init           = init_metadump_v1,
+       .write          = write_metadump_v1,
+       .finish_dump    = finish_dump_metadump_v1,
+       .release        = release_metadump_v1,
+};
+
 static int
 metadump_f(
        int             argc,
@@ -2874,7 +2872,9 @@ metadump_f(
                }
        }
 
-       ret = init_metadump();
+       metadump.mdops = &metadump1_ops;
+
+       ret = metadump.mdops->init();
        if (ret)
                goto out;
 
@@ -2897,7 +2897,7 @@ metadump_f(
 
        /* write the remaining index */
        if (!exitcode)
-               exitcode = write_index() < 0;
+               exitcode = metadump.mdops->finish_dump() < 0;
 
        if (metadump.progress_since_warning)
                fputc('\n', metadump.stdout_metadump ? stderr : stdout);
@@ -2916,7 +2916,7 @@ metadump_f(
        while (iocur_sp > start_iocur_sp)
                pop_cur();
 
-       release_metadump();
+       metadump.mdops->release();
 
 out:
        return 0;