[U-Boot] [PATCH V3 03/12] fs: don't pass NULL dev_desc to most filesystems

[Stephen Warren]

From: Stephen Warren <swarren at nvidia.com>

FAT and ext4 expect that the passed in block device descriptor not be
NULL. This causes problems on sandbox, where get_device_and_partition()
succeeds for the "host" device, yet passes back a NULL device descriptor.
Add special handling for this situation, so that the generic filesystem
commands operate as expected on sandbox.

Signed-off-by: Stephen Warren <swarren at nvidia.com>
---
v3: New patch.
---
 fs/fs.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/fs/fs.c b/fs/fs.c
index 8fe2403a46ae..653e597c3cc9 100644
--- a/fs/fs.c
+++ b/fs/fs.c
@@ -64,6 +64,7 @@ static inline void fs_close_unsupported(void)
 
 struct fstype_info {
 	int fstype;
+	bool null_dev_desc_ok;
 	int (*probe)(block_dev_desc_t *fs_dev_desc,
 		     disk_partition_t *fs_partition);
 	int (*ls)(const char *dirname);
@@ -77,6 +78,7 @@ static struct fstype_info fstypes[] = {
 #ifdef CONFIG_FS_FAT
 	{
 		.fstype = FS_TYPE_FAT,
+		.null_dev_desc_ok = false,
 		.probe = fat_set_blk_dev,
 		.close = fat_close,
 		.ls = file_fat_ls,
@@ -88,6 +90,7 @@ static struct fstype_info fstypes[] = {
 #ifdef CONFIG_FS_EXT4
 	{
 		.fstype = FS_TYPE_EXT,
+		.null_dev_desc_ok = false,
 		.probe = ext4fs_probe,
 		.close = ext4fs_close,
 		.ls = ext4fs_ls,
@@ -99,6 +102,7 @@ static struct fstype_info fstypes[] = {
 #ifdef CONFIG_SANDBOX
 	{
 		.fstype = FS_TYPE_SANDBOX,
+		.null_dev_desc_ok = true,
 		.probe = sandbox_fs_set_blk_dev,
 		.close = sandbox_fs_close,
 		.ls = sandbox_fs_ls,
@@ -109,6 +113,7 @@ static struct fstype_info fstypes[] = {
 #endif
 	{
 		.fstype = FS_TYPE_ANY,
+		.null_dev_desc_ok = true,
 		.probe = fs_probe_unsupported,
 		.close = fs_close_unsupported,
 		.ls = fs_ls_unsupported,
@@ -162,6 +167,9 @@ int fs_set_blk_dev(const char *ifname, const char *dev_part_str, int fstype)
 				fstype != info->fstype)
 			continue;
 
+		if (!fs_dev_desc && !info->null_dev_desc_ok)
+			continue;
+
 		if (!info->probe(fs_dev_desc, &fs_partition)) {
 			fs_type = info->fstype;
 			return 0;
-- 
1.8.1.5