fs: fix generic save command implementation

Fix a few issues with the generic "save" shell command, and fs_write()
function.

1) fstypes[].write wasn't filled in for some file-systems, and isn't
   checked when used, which could cause crashes/... if executing save
   on e.g. fat/ext filesystems.

2) fs_write() requires the length argument to be non-zero, since it needs
   to know exactly how many bytes to write. Adjust the comments and code
   according to this.

3) fs_write() wasn't prototyped in <fs.h> like other generic functions;
   other code should be able to call this directly rather than invoking
   the "save" shell command.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Stephen Warren 2014-02-03 13:20:59 -07:00 committed by Tom Rini
parent 16f4d9335f
commit bd6fb31fab
2 changed files with 13 additions and 6 deletions

View File

@ -75,6 +75,7 @@ static struct fstype_info fstypes[] = {
.close = fat_close,
.ls = file_fat_ls,
.read = fat_read_file,
.write = fs_write_unsupported,
},
#endif
#ifdef CONFIG_FS_EXT4
@ -84,6 +85,7 @@ static struct fstype_info fstypes[] = {
.close = ext4fs_close,
.ls = ext4fs_ls,
.read = ext4_read_file,
.write = fs_write_unsupported,
},
#endif
#ifdef CONFIG_SANDBOX
@ -212,16 +214,11 @@ int fs_write(const char *filename, ulong addr, int offset, int len)
void *buf;
int ret;
/*
* We don't actually know how many bytes are being read, since len==0
* means read the whole file.
*/
buf = map_sysmem(addr, len);
ret = info->write(filename, buf, offset, len);
unmap_sysmem(buf);
/* If we requested a specific number of bytes, check we got it */
if (ret >= 0 && len && ret != len) {
if (ret >= 0 && ret != len) {
printf("** Unable to write file %s **\n", filename);
ret = -1;
}

View File

@ -54,6 +54,16 @@ int fs_ls(const char *dirname);
*/
int fs_read(const char *filename, ulong addr, int offset, int len);
/*
* Write file "filename" to the partition previously set by fs_set_blk_dev(),
* from address "addr", starting at byte offset "offset", and writing "len"
* bytes. "offset" may be 0 to write to the start of the file. Note that not
* all filesystem types support offset!=0.
*
* Returns number of bytes read on success. Returns <= 0 on error.
*/
int fs_write(const char *filename, ulong addr, int offset, int len);
/*
* Common implementation for various filesystem commands, optionally limited
* to a specific filesystem type via the fstype parameter.