Needed to support efi file protocol. The fallback.efi loader wants to be able to read the contents of the /EFI directory to find an OS to boot.
For reference, the expected EFI semantics are described in (v2.7 of UEFI spec) in section 13.5 (page 609). Or for convenience, see:
http://wiki.phoenix.com/wiki/index.php/EFI_FILE_PROTOCOL#Read.28.29
The EFI level semantics are implemented in a later patch, so they are not too important to the understanding of this patch.
Signed-off-by: Rob Clark robdclark@gmail.com --- fs/fs.c | 25 +++++++++++++++++++++++++ include/fs.h | 21 +++++++++++++++++++++ 2 files changed, 46 insertions(+)
diff --git a/fs/fs.c b/fs/fs.c index 595ff1fe69..5ac4226ece 100644 --- a/fs/fs.c +++ b/fs/fs.c @@ -69,6 +69,12 @@ static inline int fs_uuid_unsupported(char *uuid_str) return -1; }
+static inline int fs_readdir_unsupported(const char *filename, loff_t offset, + struct fs_dirent *dent) +{ + return -ENXIO; +} + struct fstype_info { int fstype; char *name; @@ -92,6 +98,7 @@ struct fstype_info { loff_t len, loff_t *actwrite); void (*close)(void); int (*uuid)(char *uuid_str); + int (*readdir)(const char *filename, loff_t offset, struct fs_dirent *dent); };
static struct fstype_info fstypes[] = { @@ -112,6 +119,7 @@ static struct fstype_info fstypes[] = { .write = fs_write_unsupported, #endif .uuid = fs_uuid_unsupported, + .readdir = fs_readdir_unsupported, }, #endif #ifdef CONFIG_FS_EXT4 @@ -131,6 +139,7 @@ static struct fstype_info fstypes[] = { .write = fs_write_unsupported, #endif .uuid = ext4fs_uuid, + .readdir = fs_readdir_unsupported, }, #endif #ifdef CONFIG_SANDBOX @@ -146,6 +155,7 @@ static struct fstype_info fstypes[] = { .read = fs_read_sandbox, .write = fs_write_sandbox, .uuid = fs_uuid_unsupported, + .readdir = fs_readdir_unsupported, }, #endif #ifdef CONFIG_CMD_UBIFS @@ -161,6 +171,7 @@ static struct fstype_info fstypes[] = { .read = ubifs_read, .write = fs_write_unsupported, .uuid = fs_uuid_unsupported, + .readdir = fs_readdir_unsupported, }, #endif { @@ -175,6 +186,7 @@ static struct fstype_info fstypes[] = { .read = fs_read_unsupported, .write = fs_write_unsupported, .uuid = fs_uuid_unsupported, + .readdir = fs_readdir_unsupported, }, };
@@ -334,6 +346,19 @@ int fs_write(const char *filename, ulong addr, loff_t offset, loff_t len, return ret; }
+int fs_readdir(const char *filename, loff_t offset, struct fs_dirent *dent) +{ + struct fstype_info *info = fs_get_info(fs_type); + int ret; + + memset(dent, 0, sizeof(*dent)); + + ret = info->readdir(filename, offset, dent); + fs_close(); + + return ret; +} + int do_size(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], int fstype) { diff --git a/include/fs.h b/include/fs.h index 2f2aca8378..71051d7c66 100644 --- a/include/fs.h +++ b/include/fs.h @@ -79,6 +79,27 @@ int fs_write(const char *filename, ulong addr, loff_t offset, loff_t len, loff_t *actwrite);
/* + * A directory entry. + */ +struct fs_dirent { + loff_t size; + char name[256]; +}; + +/* + * fs_readdir - Read a directory. + * + * @filename: Name of file to read from + * @offset: The offset into the directory to read, ie. offset of N returns + * the N'th directory entry + * @dent: on success, filled in with directory entry + * @return 0 on success, -ENOTDIR if specified file is not a directory, + * or -ENOENT if offset is beyond last directory entry, or -ENXIO if + * operation is not supported. + */ +int fs_readdir(const char *filename, loff_t offset, struct fs_dirent *dent); + +/* * Common implementation for various filesystem commands, optionally limited * to a specific filesystem type via the fstype parameter. */