part: add partition number to disk_partition_t

From: Stephen Warren <[email protected]>

This removes the standalone cur_part_nr variable, opening the way to replacing fat_register_device() with fat_set_blk_dev().

Note that when get_partition_info() fails and we use the entire disk, the correct partition number is 0 (whole disk) not 1 (first partition), so that change is also made here.

An alternative to this (and the previous) patch might be to simply remove the partition number from the printf(). I don't know how attached people are to it.

Signed-off-by Stephen Warren <[email protected]>

Hi

Quoted 9 lines · On Wednesday 10 October 2012 12:14:00 Stephen Warren wrote:

From: Stephen Warren <[email protected]>

This removes the standalone cur_part_nr variable, opening the way to replacing fat_register_device() with fat_set_blk_dev().

Note that when get_partition_info() fails and we use the entire disk, the correct partition number is 0 (whole disk) not 1 (first partition), so that change is also made here.

Quoted 5 lines

An alternative to this (and the previous) patch might be to simply remove the partition number from the printf(). I don't know how attached people are to it.

Signed-off-by Stephen Warren <[email protected]>

Just as a heads up, in the DM any difference between a partition and a whole block device (also between different interfaces for disks) is hidden from any user code (code other than the one keeping track of partitions/disks, that only uses such information to determine whether to scan for partitions), you only get some object that can read/write blocks if you ask it nicely, and you have to make do with that (if you need more then you're probably doing something wrong).
As a result, there is no notion of partition number, and the string you are patching up here (along with many others, due to unification of disk interfaces) is changed.

Quoted 18 lines · Pavel Herrmann

Hi

Quoted 9 lines · On Wednesday 10 October 2012 12:14:00 Stephen Warren wrote:

From: Stephen Warren <[email protected]>

This removes the standalone cur_part_nr variable, opening the way to replacing fat_register_device() with fat_set_blk_dev().

Note that when get_partition_info() fails and we use the entire disk, the correct partition number is 0 (whole disk) not 1 (first partition), so that change is also made here.

Quoted 5 lines

An alternative to this (and the previous) patch might be to simply remove the partition number from the printf(). I don't know how attached people are to it.

Signed-off-by Stephen Warren <[email protected]>

Quoted 11 lines

Just as a heads up, in the DM any difference between a partition and a whole block device (also between different interfaces for disks) is hidden from any user code (code other than the one keeping track of partitions/disks, that only uses such information to determine whether to scan for partitions), you only get some object that can read/write blocks if you ask it nicely, and you have to make do with that (if you need more then you're probably doing something wrong).
As a result, there is no notion of partition number, and the string you are
patching up here (along with many others, due to unification of disk interfaces) is changed.

OK, so do you think it'd be better right now to drop patches 1 and 2 in this series, and just remove the partition number from fat.c's printf() call? That'd certainly be simple to do.

Quoted 31 lines · On Monday 15 of October 2012 10:40:25 Stephen Warren wrote:

Quoted 18 lines · Pavel Herrmann

Hi

Quoted 9 lines · On Wednesday 10 October 2012 12:14:00 Stephen Warren wrote:

From: Stephen Warren <[email protected]>

This removes the standalone cur_part_nr variable, opening the way to replacing fat_register_device() with fat_set_blk_dev().

Note that when get_partition_info() fails and we use the entire disk, the correct partition number is 0 (whole disk) not 1 (first partition), so that change is also made here.

Quoted 5 lines

An alternative to this (and the previous) patch might be to simply remove the partition number from the printf(). I don't know how attached people are to it.

Signed-off-by Stephen Warren <[email protected]>

Quoted 11 lines

Just as a heads up, in the DM any difference between a partition and a whole block device (also between different interfaces for disks) is hidden from any user code (code other than the one keeping track of partitions/disks, that only uses such information to determine whether to scan for partitions), you only get some object that can read/write blocks if you ask it nicely, and you have to make do with that (if you need more then you're probably doing something wrong).
As a result, there is no notion of partition number, and the string you are
patching up here (along with many others, due to unification of disk interfaces) is changed.

Quoted 3 lines

OK, so do you think it'd be better right now to drop patches 1 and 2 in this series, and just remove the partition number from fat.c's printf() call? That'd certainly be simple to do.

Well, in my case I have done a broader abstraction, that could be used for non-continuous partitions as well (think LVM) with minimal effort (think extend identifier structure used for searching to more than interface:number:partnumber, no changes in FS code), and partition number loses any meaning in that context.
Whether dropping the number now is an acceptable change would be up to Tom Rini, I would vote for it though, if that meant anything around here.

This makes the FAT filesystem API more consistent with other block-based
filesystems. If in the future standard multi-filesystem commands such as
"ls" or "load" are implemented, having FAT work the same way as other filesystems will be necessary.

Convert cmd_fat.c to the new API, so the code looks more like other files
implementing the same commands for other filesystems.

Signed-off-by Stephen Warren <[email protected]>

---
v3: Rebase on new fat.c cleanup patch.
v2: Fix inverted test of get_partition_info() result in fat_register_device().

---
 common/cmd_fat.c |    8 +++---
 fs/fat/fat.c     |   69
 +++++++++++++++++++++++++-----------------------------
 include/fat.h    |    1 +
 3 files changed, 37 insertions(+), 41 deletions(-)

common/cmd_fat.c +1 -1

index 5a5698b..c38302d 100644
@@ -55,7 +55,7 @@ int do_fat_fsload (cmd_tbl_t *cmdtp, int flag, int
 argc, char * const argv[])
 		return 1;
 
 	dev = dev_desc->dev;
-	if (fat_register_device(dev_desc,part)!=0) {
+	if (fat_set_blk_dev(dev_desc, &info) != 0) {
 		printf("\n** Unable to use %s %d:%d for fatload **\n",
 			argv[1], dev, part);

common/cmd_fat.c +1 -1

 		return 1;

@@ -111,7 +111,7 @@ int do_fat_ls (cmd_tbl_t *cmdtp, int flag, int
 argc, char * const argv[])
 		return 1;
 
 	dev = dev_desc->dev;
-	if (fat_register_device(dev_desc,part)!=0) {
+	if (fat_set_blk_dev(dev_desc, &info) != 0) {
 		printf("\n** Unable to use %s %d:%d for fatls **\n",
 			argv[1], dev, part);

common/cmd_fat.c +1 -1

 		return 1;

@@ -149,7 +149,7 @@ int do_fat_fsinfo (cmd_tbl_t *cmdtp, int flag,
 int argc, char * const argv[])
 		return 1;
 
 	dev = dev_desc->dev;
-	if (fat_register_device(dev_desc,part)!=0) {
+	if (fat_set_blk_dev(dev_desc, &info) != 0) {
 		printf("\n** Unable to use %s %d:%d for fatinfo **\n",
 			argv[1], dev, part);

common/cmd_fat.c +1 -1

 		return 1;

@@ -185,7 +185,7 @@ static int do_fat_fswrite(cmd_tbl_t *cmdtp, int
 flag,
 
 	dev = dev_desc->dev;
 
-	if (fat_register_device(dev_desc, part) != 0) {
+	if (fat_set_blk_dev(dev_desc, &info) != 0) {
 		printf("\n** Unable to use %s %d:%d for fatwrite **\n",
 			argv[1], dev, part);

common/cmd_fat.c +0 -0

 		return 1;

fs/fat/fat.c +3 -37

index 2863c4b..a6fc07c 100644
@@ -61,46 +61,12 @@ static int disk_read(__u32 block, __u32
 nr_blocks, void *buf)
 			cur_part_info.start + block, nr_blocks, buf);
 }
 
-int fat_register_device(block_dev_desc_t * dev_desc, int part_no)
+int fat_set_blk_dev(block_dev_desc_t *dev_desc, disk_partition_t
 *info)
 {
 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
 
-	/* First close any currently found FAT filesystem */
-	cur_dev = NULL;
-
-#if (defined(CONFIG_CMD_IDE) || \
-     defined(CONFIG_CMD_SATA) || \
-     defined(CONFIG_CMD_SCSI) || \
-     defined(CONFIG_CMD_USB) || \
-     defined(CONFIG_MMC) || \
-     defined(CONFIG_SYSTEMACE) )
-
-	/* Read the partition table, if present */
-	if (!get_partition_info(dev_desc, part_no, &cur_part_info)) {
-		cur_dev = dev_desc;
-	}
-#endif
-
-	/* Otherwise it might be a superfloppy (whole-disk FAT filesystem)
 */
-	if (!cur_dev) {
-		if (part_no != 0) {
-			printf("** Partition %d not valid on device %d **\n",
-					part_no, dev_desc->dev);
-			return -1;
-		}
-
-		cur_dev = dev_desc;
-		cur_part_info.part = 0;
-		cur_part_info.start = 0;
-		cur_part_info.size = dev_desc->lba;
-		cur_part_info.blksz = dev_desc->blksz;
-		cur_part_info.name[0] = 0;
-		cur_part_info.type[0] = 0;
-		cur_part_info.bootable = 0;
-#ifdef CONFIG_PARTITION_UUIDS
-		cur_part_info.uuid[0] = 0;
-#endif
-	}
+	cur_dev = dev_desc;
+	cur_part_info = *info;

fs/fat/fat.c +29 -0

 	/* Make sure it has a valid FAT header */
 	if (disk_read(0, 1, buffer) != 1) {

@@ -124,6 +90,35 @@ int fat_register_device(block_dev_desc_t *
 dev_desc, int part_no)
 	return -1;
 }
 
+int fat_register_device(block_dev_desc_t *dev_desc, int part_no)
+{
+	disk_partition_t info;
+
+	/* First close any currently found FAT filesystem */
+	cur_dev = NULL;
+
+	/* Read the partition table, if present */
+	if (get_partition_info(dev_desc, part_no, &info)) {
+		if (part_no != 0) {
+			printf("** Partition %d not valid on device %d **\n",
+					part_no, dev_desc->dev);
+			return -1;
+		}
+
+		info.part = 0;
+		info.start = 0;
+		info.size = dev_desc->lba;
+		info.blksz = dev_desc->blksz;
+		info.name[0] = 0;
+		info.type[0] = 0;
+		info.bootable = 0;
+#ifdef CONFIG_PARTITION_UUIDS
+		info.uuid[0] = 0;
+#endif
+	}
+
+	return fat_set_blk_dev(dev_desc, &info);
+}
 
 /*

* Get the first occurence of a directory delimiter ('/' or '\') in a string.

include/fat.h +1 -0

index cc85b06..706cd7a 100644
@@ -212,6 +212,7 @@ long file_fat_read_at(const char *filename,
 unsigned long pos, void *buffer,
 		      unsigned long maxsize);
 long file_fat_read(const char *filename, void *buffer, unsigned long
 maxsize);
 const char *file_getfsname(int idx);
+int fat_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info);
 int fat_register_device(block_dev_desc_t *dev_desc, int part_no);

int file_fat_write(const char *filename, void *buffer, unsigned long maxsize);