[PATCH V2 08/23] metadump: Introduce metadump v1 operations

From: Chandan Babu R <chandan.babu@oracle.com>
To: linux-xfs@vger.kernel.org
Cc: Chandan Babu R <chandan.babu@oracle.com>,
	djwong@kernel.org, cem@kernel.org
Subject: [PATCH V2 08/23] metadump: Introduce metadump v1 operations
Date: Tue,  6 Jun 2023 14:57:51 +0530	[thread overview]
Message-ID: <20230606092806.1604491-9-chandan.babu@oracle.com> (raw)
In-Reply-To: <20230606092806.1604491-1-chandan.babu@oracle.com>

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.

Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
---
 db/metadump.c | 123 +++++++++++++++++++++++++-------------------------
 1 file changed, 61 insertions(+), 62 deletions(-)

diff --git a/db/metadump.c b/db/metadump.c
index 266d3413..287e8f91 100644
--- a/db/metadump.c
+++ b/db/metadump.c
@@ -151,59 +151,6 @@ 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
@@ -240,15 +187,16 @@ 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;
@@ -3010,7 +2958,7 @@ done:
 }
 
 static int
-init_metadump(void)
+init_metadump_v1(void)
 {
 	metadump.metablock = (xfs_metablock_t *)calloc(BBSIZE + 1, BBSIZE);
 	if (metadump.metablock == NULL) {
@@ -3051,12 +2999,61 @@ init_metadump(void)
 	return 0;
 }
 
+static int
+end_write_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,
+	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 = end_write_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,
+	.end_write	= end_write_metadump_v1,
+	.release	= release_metadump_v1,
+};
+
 static int
 metadump_f(
 	int 		argc,
@@ -3193,7 +3190,9 @@ metadump_f(
 		}
 	}
 
-	ret = init_metadump();
+	metadump.mdops = &metadump1_ops;
+
+	ret = metadump.mdops->init();
 	if (ret)
 		goto out;
 
@@ -3216,7 +3215,7 @@ metadump_f(
 
 	/* write the remaining index */
 	if (!exitcode)
-		exitcode = write_index() < 0;
+		exitcode = metadump.mdops->end_write() < 0;
 
 	if (metadump.progress_since_warning)
 		fputc('\n', metadump.stdout_metadump ? stderr : stdout);
@@ -3235,7 +3234,7 @@ metadump_f(
 	while (iocur_sp > start_iocur_sp)
 		pop_cur();
 
-	release_metadump();
+	metadump.mdops->release();
 
 out:
 	return 0;
-- 
2.39.1

