From 4bbcc965f995564870ca02606137e60e873e0a1f Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Sat, 9 Sep 2017 13:15:55 -0400 Subject: fs: add fs_readdir() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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. Modelled after POSIX opendir()/readdir()/closedir(). Unlike the other fs APIs, this is stateful (ie. state is held in the FS_DIR "directory stream"), to avoid re-traversing of the directory structure at each step. The directory stream must be released with closedir() when it is no longer needed. Signed-off-by: Rob Clark Reviewed-by: Łukasz Majewski Reviewed-by: Simon Glass --- fs/fs.c | 104 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) (limited to 'fs/fs.c') diff --git a/fs/fs.c b/fs/fs.c index 13cd3626c6..fc0c953fcb 100644 --- a/fs/fs.c +++ b/fs/fs.c @@ -21,6 +21,7 @@ DECLARE_GLOBAL_DATA_PTR; static struct blk_desc *fs_dev_desc; +static int fs_dev_part; static disk_partition_t fs_partition; static int fs_type = FS_TYPE_ANY; @@ -69,6 +70,12 @@ static inline int fs_uuid_unsupported(char *uuid_str) return -1; } +static inline int fs_opendir_unsupported(const char *filename, + struct fs_dir_stream **dirs) +{ + return -EACCES; +} + struct fstype_info { int fstype; char *name; @@ -92,6 +99,20 @@ struct fstype_info { loff_t len, loff_t *actwrite); void (*close)(void); int (*uuid)(char *uuid_str); + /* + * Open a directory stream. On success return 0 and directory + * stream pointer via 'dirsp'. On error, return -errno. See + * fs_opendir(). + */ + int (*opendir)(const char *filename, struct fs_dir_stream **dirsp); + /* + * Read next entry from directory stream. On success return 0 + * and directory entry pointer via 'dentp'. On error return + * -errno. See fs_readdir(). + */ + int (*readdir)(struct fs_dir_stream *dirs, struct fs_dirent **dentp); + /* see fs_closedir() */ + void (*closedir)(struct fs_dir_stream *dirs); }; static struct fstype_info fstypes[] = { @@ -112,6 +133,7 @@ static struct fstype_info fstypes[] = { .write = fs_write_unsupported, #endif .uuid = fs_uuid_unsupported, + .opendir = fs_opendir_unsupported, }, #endif #ifdef CONFIG_FS_EXT4 @@ -131,6 +153,7 @@ static struct fstype_info fstypes[] = { .write = fs_write_unsupported, #endif .uuid = ext4fs_uuid, + .opendir = fs_opendir_unsupported, }, #endif #ifdef CONFIG_SANDBOX @@ -146,6 +169,7 @@ static struct fstype_info fstypes[] = { .read = fs_read_sandbox, .write = fs_write_sandbox, .uuid = fs_uuid_unsupported, + .opendir = fs_opendir_unsupported, }, #endif #ifdef CONFIG_CMD_UBIFS @@ -161,6 +185,7 @@ static struct fstype_info fstypes[] = { .read = ubifs_read, .write = fs_write_unsupported, .uuid = fs_uuid_unsupported, + .opendir = fs_opendir_unsupported, }, #endif { @@ -175,6 +200,7 @@ static struct fstype_info fstypes[] = { .read = fs_read_unsupported, .write = fs_write_unsupported, .uuid = fs_uuid_unsupported, + .opendir = fs_opendir_unsupported, }, }; @@ -226,6 +252,31 @@ int fs_set_blk_dev(const char *ifname, const char *dev_part_str, int fstype) if (!fs_dev_desc && !info->null_dev_desc_ok) continue; + if (!info->probe(fs_dev_desc, &fs_partition)) { + fs_type = info->fstype; + fs_dev_part = part; + return 0; + } + } + + return -1; +} + +/* set current blk device w/ blk_desc + partition # */ +int fs_set_blk_dev_with_part(struct blk_desc *desc, int part) +{ + struct fstype_info *info; + int ret, i; + + if (part >= 1) + ret = part_get_info(desc, part, &fs_partition); + else + ret = part_get_info_whole_disk(desc, &fs_partition); + if (ret) + return ret; + fs_dev_desc = desc; + + for (i = 0, info = fstypes; i < ARRAY_SIZE(fstypes); i++, info++) { if (!info->probe(fs_dev_desc, &fs_partition)) { fs_type = info->fstype; return 0; @@ -334,6 +385,59 @@ int fs_write(const char *filename, ulong addr, loff_t offset, loff_t len, return ret; } +struct fs_dir_stream *fs_opendir(const char *filename) +{ + struct fstype_info *info = fs_get_info(fs_type); + struct fs_dir_stream *dirs = NULL; + int ret; + + ret = info->opendir(filename, &dirs); + fs_close(); + if (ret) { + errno = -ret; + return NULL; + } + + dirs->desc = fs_dev_desc; + dirs->part = fs_dev_part; + + return dirs; +} + +struct fs_dirent *fs_readdir(struct fs_dir_stream *dirs) +{ + struct fstype_info *info; + struct fs_dirent *dirent; + int ret; + + fs_set_blk_dev_with_part(dirs->desc, dirs->part); + info = fs_get_info(fs_type); + + ret = info->readdir(dirs, &dirent); + fs_close(); + if (ret) { + errno = -ret; + return NULL; + } + + return dirent; +} + +void fs_closedir(struct fs_dir_stream *dirs) +{ + struct fstype_info *info; + + if (!dirs) + return; + + fs_set_blk_dev_with_part(dirs->desc, dirs->part); + info = fs_get_info(fs_type); + + info->closedir(dirs); + fs_close(); +} + + int do_size(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], int fstype) { -- cgit v1.2.3