format: add support for dev_fill() and extra dev_*() debugging.

Support an fs_io dev_fill().
This helps with devices that actually already return 0 on uninitialized
data. It also helps with in memory devices using sparse libs: don't
allocate a block of 0s.

Signed-off-by: JP Abgrall <jpa@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

3 files changed, 33 insertions, 2 deletions

diff --git a/include/f2fs_fs.h b/include/f2fs_fs.h
index 7210604..095d755 100644
--- a/include/f2fs_fs.h
+++ b/include/f2fs_fs.h
@@ -665,6 +665,8 @@ extern int f2fs_get_device_info(struct f2fs_configuration *);
 
 extern int dev_read(void *, __u64, size_t);
 extern int dev_write(void *, __u64, size_t);
+/* All bytes in the buffer must be 0 use dev_fill(). */
+extern int dev_fill(void *, __u64, size_t);
 
 extern int dev_read_block(void *, __u64);
 extern int dev_read_blocks(void *, __u64, __u32 );
diff --git a/lib/libf2fs_io.c b/lib/libf2fs_io.c
index e48dd1a..5f0a547 100644
--- a/lib/libf2fs_io.c
+++ b/lib/libf2fs_io.c
@@ -49,6 +49,18 @@ int dev_write(void *buf, __u64 offset, size_t len)
 	return 0;
 }
 
+int dev_fill(void *buf, __u64 offset, size_t len)
+{
+	/* Only allow fill to zero */
+	if (*((__u8*)buf))
+		return -1;
+	if (lseek64(config.fd, (off64_t)offset, SEEK_SET) < 0)
+		return -1;
+	if (write(config.fd, buf, len) < 0)
+		return -1;
+	return 0;
+}
+
 int dev_read_block(void *buf, __u64 blk_addr)
 {
 	return dev_read(buf, blk_addr * F2FS_BLKSIZE, F2FS_BLKSIZE);
diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
index a46e60e..31b4422 100644
--- a/mkfs/f2fs_format.c
+++ b/mkfs/f2fs_format.c
@@ -376,10 +376,11 @@ static int f2fs_init_sit_area(void)
 	sit_seg_addr = le32_to_cpu(super_block.sit_blkaddr);
 	sit_seg_addr *= blk_size;
 
+	DBG(1, "\tFilling sit area at offset 0x%08"PRIx64"\n", sit_seg_addr);
 	for (index = 0;
 		index < (le32_to_cpu(super_block.segment_count_sit) / 2);
 								index++) {
-		if (dev_write(zero_buf, sit_seg_addr, seg_size)) {
+		if (dev_fill(zero_buf, sit_seg_addr, seg_size)) {
 			MSG(1, "\tError: While zeroing out the sit area \
 					on disk!!!\n");
 			return -1;
@@ -411,10 +412,11 @@ static int f2fs_init_nat_area(void)
 	nat_seg_addr = le32_to_cpu(super_block.nat_blkaddr);
 	nat_seg_addr *= blk_size;
 
+	DBG(1, "\tFilling nat area at offset 0x%08"PRIx64"\n", nat_seg_addr);
 	for (index = 0;
 		index < (le32_to_cpu(super_block.segment_count_nat) / 2);
 								index++) {
-		if (dev_write(nat_buf, nat_seg_addr, seg_size)) {
+		if (dev_fill(nat_buf, nat_seg_addr, seg_size)) {
 			MSG(1, "\tError: While zeroing out the nat area \
 					on disk!!!\n");
 			return -1;
@@ -510,6 +512,7 @@ static int f2fs_write_check_point_pack(void)
 	cp_seg_blk_offset = le32_to_cpu(super_block.segment0_blkaddr);
 	cp_seg_blk_offset *= blk_size_bytes;
 
+	DBG(1, "\tWriting main segments, ckp at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(ckp, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the ckp to disk!!!\n");
 		return -1;
@@ -523,6 +526,7 @@ static int f2fs_write_check_point_pack(void)
 	sum->entries[0].ofs_in_node = 0;
 
 	cp_seg_blk_offset += blk_size_bytes;
+	DBG(1, "\tWriting segment summary for data, ckp at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(sum, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the sum_blk to disk!!!\n");
 		return -1;
@@ -533,6 +537,7 @@ static int f2fs_write_check_point_pack(void)
 	SET_SUM_TYPE((&sum->footer), SUM_TYPE_DATA);
 
 	cp_seg_blk_offset += blk_size_bytes;
+	DBG(1, "\tWriting segment summary, ckp at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(sum, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the sum_blk to disk!!!\n");
 		return -1;
@@ -562,6 +567,7 @@ static int f2fs_write_check_point_pack(void)
 	sum->sit_j.entries[5].se.vblocks = cpu_to_le16((CURSEG_COLD_DATA << 10));
 
 	cp_seg_blk_offset += blk_size_bytes;
+	DBG(1, "\tWriting data sit for root, at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(sum, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the sum_blk to disk!!!\n");
 		return -1;
@@ -575,6 +581,7 @@ static int f2fs_write_check_point_pack(void)
 	sum->entries[0].ofs_in_node = 0;
 
 	cp_seg_blk_offset += blk_size_bytes;
+	DBG(1, "\tWriting Segment summary for node blocks, at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(sum, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the sum_blk to disk!!!\n");
 		return -1;
@@ -585,6 +592,7 @@ static int f2fs_write_check_point_pack(void)
 	SET_SUM_TYPE((&sum->footer), SUM_TYPE_NODE);
 
 	cp_seg_blk_offset += blk_size_bytes;
+	DBG(1, "\tWriting Segment summary for data block (1/2), at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(sum, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the sum_blk to disk!!!\n");
 		return -1;
@@ -594,6 +602,7 @@ static int f2fs_write_check_point_pack(void)
 	memset(sum, 0, sizeof(struct f2fs_summary_block));
 	SET_SUM_TYPE((&sum->footer), SUM_TYPE_NODE);
 	cp_seg_blk_offset += blk_size_bytes;
+	DBG(1, "\tWriting Segment summary for data block (2/2), at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(sum, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the sum_blk to disk!!!\n");
 		return -1;
@@ -601,6 +610,7 @@ static int f2fs_write_check_point_pack(void)
 
 	/* 8. cp page2 */
 	cp_seg_blk_offset += blk_size_bytes;
+	DBG(1, "\tWriting cp page2, at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(ckp, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the ckp to disk!!!\n");
 		return -1;
@@ -617,6 +627,7 @@ static int f2fs_write_check_point_pack(void)
 	cp_seg_blk_offset = (le32_to_cpu(super_block.segment0_blkaddr) +
 				config.blks_per_seg) *
 				blk_size_bytes;
+	DBG(1, "\tWriting cp page 1 of checkpoint pack 2, at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(ckp, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the ckp to disk!!!\n");
 		return -1;
@@ -624,6 +635,7 @@ static int f2fs_write_check_point_pack(void)
 
 	/* 10. cp page 2 of check point pack 2 */
 	cp_seg_blk_offset += blk_size_bytes * (le32_to_cpu(ckp->cp_pack_total_block_count) - 1);
+	DBG(1, "\tWriting cp page 2 of checkpoint pack 2, at offset 0x%08"PRIx64"\n", cp_seg_blk_offset);
 	if (dev_write(ckp, cp_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the ckp to disk!!!\n");
 		return -1;
@@ -643,6 +655,7 @@ static int f2fs_write_super_block(void)
 
 	memcpy(zero_buff + F2FS_SUPER_OFFSET, &super_block,
 						sizeof(super_block));
+	DBG(1, "\tWriting super block, at offset 0x%08x\n", 0);
 	for (index = 0; index < 2; index++) {
 		if (dev_write(zero_buff, index * F2FS_BLKSIZE, F2FS_BLKSIZE)) {
 			MSG(1, "\tError: While while writing supe_blk \
@@ -709,6 +722,7 @@ static int f2fs_write_root_inode(void)
 					config.blks_per_seg;
         main_area_node_seg_blk_offset *= blk_size_bytes;
 
+	DBG(1, "\tWriting root inode (hot node), at offset 0x%08"PRIx64"\n", main_area_node_seg_blk_offset);
 	if (dev_write(raw_node, main_area_node_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the raw_node to disk!!!\n");
 		return -1;
@@ -722,6 +736,7 @@ static int f2fs_write_root_inode(void)
 					config.blks_per_seg;
         main_area_node_seg_blk_offset *= blk_size_bytes;
 
+	DBG(1, "\tWriting root inode (warm node), at offset 0x%08"PRIx64"\n", main_area_node_seg_blk_offset);
 	if (dev_write(raw_node, main_area_node_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the raw_node to disk!!!\n");
 		return -1;
@@ -759,6 +774,7 @@ static int f2fs_update_nat_root(void)
 	nat_seg_blk_offset = le32_to_cpu(super_block.nat_blkaddr);
 	nat_seg_blk_offset *= blk_size_bytes;
 
+	DBG(1, "\tWriting nat root, at offset 0x%08"PRIx64"\n", nat_seg_blk_offset);
 	if (dev_write(nat_blk, nat_seg_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the nat_blk set0 to disk!\n");
 		return -1;
@@ -799,6 +815,7 @@ static int f2fs_add_default_dentry_root(void)
 				config.blks_per_seg;
 	data_blk_offset *= blk_size_bytes;
 
+	DBG(1, "\tWriting default dentry root, at offset 0x%08"PRIx64"\n", data_blk_offset);
 	if (dev_write(dent_blk, data_blk_offset, F2FS_BLKSIZE)) {
 		MSG(1, "\tError: While writing the dentry_blk to disk!!!\n");
 		return -1;